U.S. patent application number 16/784391 was filed with the patent office on 2021-01-14 for processing biomass.
The applicant listed for this patent is XYLECO, INC.. Invention is credited to Marshall Medoff.
Application Number | 20210009911 16/784391 |
Document ID | / |
Family ID | 1000005120460 |
Filed Date | 2021-01-14 |
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United States Patent
Application |
20210009911 |
Kind Code |
A1 |
Medoff; Marshall |
January 14, 2021 |
PROCESSING BIOMASS
Abstract
Techniques for processing biomass are disclosed herein. A method
of preparing cellulosic ethanol having 100% biogenic carbon content
as determined by ASTM 6866-18, includes treating ground corn cobs
with electron beam radiation and saccharifying the irradiated
ground corn cob to produce sugars. The method also includes
fermenting the sugars with a microorganism. In addition, an
unblended cellulosic-biomass derived gasoline with a research
octane number of greater than about 87, as determined by ASTM D2699
is disclosed.
Inventors: |
Medoff; Marshall;
(Brookline, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
XYLECO, INC. |
Wakefield |
MA |
US |
|
|
Family ID: |
1000005120460 |
Appl. No.: |
16/784391 |
Filed: |
February 7, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16198537 |
Nov 21, 2018 |
10597595 |
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16784391 |
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PCT/US2018/057878 |
Oct 26, 2018 |
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16198537 |
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62670411 |
May 11, 2018 |
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62660611 |
Apr 20, 2018 |
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62656318 |
Apr 11, 2018 |
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62646204 |
Mar 21, 2018 |
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62641216 |
Mar 9, 2018 |
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62578132 |
Oct 27, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10L 2270/023 20130101;
C10G 2300/1011 20130101; C10G 3/45 20130101; C10G 2300/308
20130101; C12P 19/12 20130101; C12P 7/10 20130101; C10G 2300/305
20130101; C10G 3/47 20130101; C10L 2200/0469 20130101; C10G
2300/301 20130101; C10G 2300/1014 20130101; C12P 19/02 20130101;
C10G 3/42 20130101; C10L 1/023 20130101; C10G 2300/202 20130101;
C10G 3/48 20130101; C10L 1/06 20130101; C10G 3/49 20130101; C12P
7/649 20130101; C10G 2300/201 20130101; C12P 7/16 20130101 |
International
Class: |
C10L 1/06 20060101
C10L001/06; C10G 3/00 20060101 C10G003/00; C12P 7/64 20060101
C12P007/64; C12P 7/16 20060101 C12P007/16; C12P 19/02 20060101
C12P019/02; C10L 1/02 20060101 C10L001/02; C12P 7/10 20060101
C12P007/10; C12P 19/12 20060101 C12P019/12 |
Claims
1-218. (canceled)
219. A method of making a cellulosic-biomass derived gasoline, the
method comprising: providing an alcohol comprising a
cellulosic-biomass derived alcohol, and catalytically processing
the alcohol to an unblended gasoline, wherein the unblended
gasoline has a research octane number of greater than about 87, as
determined by ASTM D2699.
220. The method of claim 219, wherein the unblended gasoline also
has a motor octane number of greater than about 85, as determined
by ASTM D2700.
221. The method of claim 219, wherein the alcohol comprises
ethanol.
222. The method of claim 219, wherein catalytically processing the
alcohol comprises passing hydrous ethanol through a packed column,
the column including a zeolite.
223. The method of claim 222, wherein the hydrous ethanol contains
greater than about 40 percent water by weight.
224. The method of claim 222, wherein the catalytically processing
the alcohol further comprises a nitrogen carrier gas to aid in the
passing of the hydrous ethanol through the packed column.
225. The method of claim 222, wherein the zeolite comprises
HZSM-5.
226. The method of claim 225, wherein the HZSM-5 includes a metal
produced by solvent impregnation.
227. The method of claim 219, wherein the unblended gasoline has a
benzene content of less than 1 percent by weight.
228. The method of claim 219, wherein the unblended gasoline has an
aromatic content of greater than 25 percent by weight.
229. The method of claim 219, wherein the method further comprises
preheating the alcohol prior to catalytically processing the
alcohol.
230. The method of claim 219, wherein the biogenic content of the
unblended gasoline is greater than about 90 percent by weight.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 16/198,537, filed Nov. 21, 2018, which is a continuation of
International Patent Application No. PCT/US2018/057878, filed Oct.
26, 2018, titled "Processing Biomass" which claims priority to U.S.
Provisional Application No. 62/578,132, filed Oct. 27, 2017, titled
"Processing Biomass", U.S. Provisional Application No. 62/641,216,
filed Mar. 9, 2018, titled "Processing Biomass", U.S. Provisional
Application No. 62/646,204, filed Mar. 21, 2018, titled "Processing
Biomass", U.S. Provisional Application No. 62/656,318, filed Apr.
11, 2018, titled "Processing Biomass", U.S. Provisional Application
No. 62/660,611, filed Apr. 20, 2018, titled "Processing Biomass",
and U.S. Provisional Application No. 62/670,411, filed May 11,
2018, titled "Processing Biomass", the entire contents of each
application are incorporated by reference herein in their
entirety.
TECHNICAL FIELD
[0002] This invention relates to processing biomass into useful
products, such as biofuel.
BACKGROUND
[0003] Biomass, particularly biomass waste, is abundantly
available. It would be useful to derive materials and fuel, such as
ethanol, from biomass.
[0004] There is presently interest in producing biofuels from a
wide variety of feedstocks, in order to provide suitable
replacements for fossil fuels. The production of biofuels is
desirable because the biosphere is presently overburdened by carbon
emissions produced from fossil fuels. The burning of fuels
presently contributes to an annual release of 4 billion metric tons
of carbon dioxide into the atmosphere and the injection of 2
billion metric tons of carbon dioxide into the world's oceans. By
using biomass (an efficient CO.sub.2 sequestrator) as the source of
fuel, the energy and transportation industries can reduce the
release of additional carbon emissions by the mining and refining
of fossil fuels.
SUMMARY
[0005] In one aspect, a method for producing fuel includes
processing a cellulosic and/or lignocellulosic biomass to obtain a
feedstock containing one or more saccharide units or saccharide
derivative units, and converting the feedstock containing one or
more saccharide units or saccharide derivative units, either
directly (e.g., by deoxygenation) or through one or more processes
(e.g., catalytically, chemically, or biologically) into a fuel
(e.g., biofuel).
[0006] In one or more embodiments, the saccharide unit includes
mono- or disaccharides.
[0007] In one or more embodiments, the saccharide unit is processed
into an intermediate alcohol using chemical processes and/or
catalytic processes.
[0008] In one or more embodiments, the intermediate (e.g., an
alcohol, ester, acid, hydrocarbon) is processed into a fuel (e.g.,
biofuel) using one or more catalytic processes.
[0009] One of the advantages of the methods described herein is the
efficient conversion of biomass to fuel with minimal loss of
energy-producing molecular mass. For example, high-value
intermediates or building blocks are produced using readily
available high-throughput systems such as flow reactors and
trickle-bed reactors and cost-effective recyclable catalysts.
[0010] In other aspects, the generation of fuel from the processes
described herein may further result in lower carbon footprint.
Unlike conventional fuels that are mined or drilled, biomass
sequesters carbon dioxide from the atmosphere. Green plants and
algae use photosynthesis to convert carbon dioxide (CO.sub.2) into
sugar, cellulose and other carbon-containing carbohydrates that
they use for food and growth. Trees, in particular, are able to
lock up large amounts of carbon in their wood, and continue to add
carbon as they grow. When such biomass is converted into fuel, the
process uses sequestered carbon (which may have released some of
its carbon back into the atmosphere by normal decay processes
anyway, instead of introducing additional carbon from oil, coal and
natural gas resources.
[0011] In one aspect, the processes described herein provide an
improved method of generating transportation fuel, for example,
aviation fuel, from biomass. Thus, environment-friendly, low-carbon
footprint aviation fuel can be generated by the invention by the
catalytic conversion of processed biomass and/or biomass-derived
products. Blending ethanol with gasoline is an established to lower
carbon footprint of gasoline, but same option is not available for
aviation fuel. Thus, aviation fuel will see the benefits of this
process because there currently is no alternative available.
[0012] In one aspect, provided herein is an improved method of
generating fuel comprising catalytic processing of biomass-derived
building blocks to produce a hydrocarbon mixture containing a
higher amount of higher molecular weight hydrocarbons such as
C5-C18 than lower molecular weight hydrocarbons such as C1-C4. In
one embodiment, the amount of C1-C4 is less than about 5% by
weight.
[0013] In one aspect, provided herein is an improved method of
generating fuel comprising catalytic processing of biomass-derived
building blocks to produce a hydrocarbon mixture containing a
higher amount of saturated hydrocarbons such as alkanes and
cycloalkanes than unsaturated hydrocarbons such as alkenes and
arenes. In one embodiment, the amount of unsaturated hydrocarbons
is less than about 30% by weight.
[0014] In one aspect, provided herein is an improved method of
generating fuel comprising catalytic processing of biomass-derived
building blocks to produce a hydrocarbon mixture containing a
higher amount of non-aromatic compounds than aromatic compounds. In
one embodiment, the amount of aromatic compounds is less than 25%
by weight.
[0015] In one aspect, provided herein is an improved method of
generating fuel comprising catalytic processing of biomass-derived
building blocks to produce a hydrocarbon mixture containing a
higher amount of even-numbered hydrocarbons than odd-numbered
hydrocarbons.
[0016] In one aspect, provided herein is an improved method of
generating fuel comprising catalytic processing of biomass-derived
building blocks to produce a hydrocarbon mixture characterized by
one or more of the following characteristics: a higher amount of
higher molecular weight hydrocarbons such as C5-C18 than lower
molecular weight hydrocarbons such as C1-C4, a higher amount of
saturated hydrocarbons such as alkanes and cycloalkanes than
unsaturated hydrocarbons such as alkenes and arenes, a higher
amount of non-aromatic compounds than aromatic compounds, and a
higher amount of even-numbered hydrocarbons than odd-numbered
hydrocarbons.
[0017] In one aspect, provided herein is a method of generating
ethanol from different types of biomass, such that the ethanol
generated from one type of biomass may have unique composition and
properties compared to that generated from another type of biomass.
In one embodiment, described herein is a process of generating
ethanol from lignocellulosic biomass that has a unique composition
and property compared to ethanol generated from non-lignocellulosic
biomass. In one embodiment, described herein is a process of
generating ethanol from recalcitrance-reduced biomass, wherein the
composition of the ethanol generated from recalcitrance-reduced
biomass is different from that of non-recalcitrance-reduced
biomass. Also, provided herein is ethanol of unique composition
prepared by the processes described herein. In one embodiment, the
ethanol composition contains ethanol and about 0.02% acetone, about
0.11 to about 2.5% methanol, about 0.18% n-propanol, about 0.12% of
2-methyl propanol, about 0.01% n-butanol, about 0.53% 2-methyl
butanol and about 8.5% isopropyl alcohol. In one aspect, provided
herein is a method of converting the ethanol of unique composition
described above to other compositions such as hydrocarbons, which
are also characterized by unique composition and properties. Thus,
in one aspect a product derived from ethanol obtained from one type
of biomass may have a different composition and property than a
product derived from ethanol obtained from a different type of
biomass. For example, a product derived from lignocellulosic
ethanol may have a different composition and property than one
derived from non-lignocellulosic ethanol. In one embodiment, raw
ethanol is used for producing value-added products like
hydrocarbons. Raw ethanol is a form of undistilled or partially
distilled ethanol. For example, the ethanol generated by the
fermentation of biomass-derived materials such as glucose derived
from sugars, starch or cellulosic materials may be filtered from
the fermentation broth and either subjected to partial distillation
or no distillation to produce raw ethanol. The raw ethanol thus
produced can be used as the building block for producing
value-added products such as hydrocarbons. In some embodiments, the
raw ethanol contains about 1% to about 2% water, about 2% to about
3% water, about 3% to about 4% water, about 4% to about 5% water,
about 5% to about 6% water, about 6% to about 7% water, about 7% to
about 8% water, about 8% to about 9% water, about 9% to about 10%
water, about 10% to about 20% water, about 20% to about 30% water,
about 30% to about 40% water, about 40% to about 50% water, about
50% to about 60% water, about 60% to about 70% water, about 70% to
about 80% water, about 80% to about 90% water by weight, or in a
range bounded by any numerical value stated herein above.
[0018] In one aspect, provided herein are methods of reducing
catalytic deactivation, by either developing deactivation-resistant
catalysts or providing methods of regenerating catalysts from
deactivated catalysts.
[0019] In one aspect, provided herein are methods of catalytically
converting biomass-derived ethanol to hydrocarbon fuel in one step,
without requiring additional steps such as reforming, blending or
hydrogenation.
[0020] In one aspect, provided herein are catalytic compositions
for efficient conversion of biomass-derived ethanol to hydrocarbon
fuel in one step, without requiring additional steps such as
reforming, blending or hydrogenation. Also provided are methods of
preparing such catalytic compositions. For example, disclosed
herein are mono-metallic catalytic compositions such as Ru/HZSM-5
catalysts containing about 0.1-20% of Ru, Pd/HZSM-5 catalysts
containing about 0.1-20% of Pd, Pt/HZSM-5 catalysts containing
about 0.1-20% of Pt, Pt/H.sub.3PO.sub.4-Al.sub.2O.sub.3 catalysts
containing about 0.1-20% of Pt, and 0.5% Pt/5%
H.sub.3BO.sub.3-Al.sub.2O.sub.3 containing 0.1-20% of Pt. Also,
disclosed are bi-metallic catalytic compositions such as
Pt--Sn/Al.sub.2O.sub.3 catalysts containing about 0.1-20% Pt (w/w)
and about 0.1-20% Sn (w/w), Pt--Bi/Al.sub.2O.sub.3 catalysts
containing about 0.1-20% Pt (w/w) and about 0.1-20% Bi (w/w), and
Pt--Ba/Al.sub.2O.sub.3 catalysts containing about 0.1-20% Pt (w/w)
and about 0.1-20% Ba (w/w). Additionally, disclosed herein are
tri-metallic catalyst compositions such as
Pt--Sn--Re/Al.sub.2O.sub.3 catalysts containing about 0.1-20% Pt
(w/w), about 0.1-20% Sn and about 0.1-20% Re (w/w),
Pt--Sn--Bi/Al.sub.2O.sub.3 catalysts containing about 0.1-20% Pt
(w/w), about 0.1-20% Sn and about 0.1-20% Bi (w/w), and
Pt--Sn--Ba/Al.sub.2O.sub.3 catalysts containing about 0.1-20% Pt
(w/w), about 0.1-20% Sn and about 0.1-20% Ba (w/w).
[0021] In one aspect, provided herein are methods of catalytically
converting biomass-derived ethanol to hydrocarbon fuel in one step,
wherein the hydrocarbon mixture contains a higher amount of liquid
hydrocarbon than gaseous hydrocarbon at standard temperature and
pressure. For example, in one embodiment, the hydrocarbon mixture
produced by the processes described herein contains greater than
about 10% (w/w), greater than about 20% (w/w), greater than about
30% (w/w), greater than about 40% (w/w), greater than about 50%
(w/w), greater than about 60% (w/w), greater than about 70% (w/w),
greater than about 80% (w/w), or greater than about 90% (w/w) of
liquid hydrocarbon at standard temperature and pressure.
[0022] In one aspect, provided herein are methods of catalytically
converting biomass-derived ethanol to hydrocarbon fuel in one step,
wherein the largest amount of non-hydrocarbon by-product is
water.
[0023] The inventors of the present invention developed catalytic
compositions that provide high yields of higher molecular
hydrocarbons. By mixing metals which were known to provide high
yield of lower molecular weight hydrocarbons with other
low-activity metals, the inventors of the present invention have
developed catalytic compositions, which unexpectedly provided high
yields of higher molecular hydrocarbons.
[0024] The disclosed methods provide several advantages. For
example, they allow for the direct conversion of alcohols, such as
ethanol, to fuel such as BTEX, gasoline, kerosene, and jet fuel in
a single step without reforming, blending or hydrogenation. In one
embodiment, they provide a safer process by using inert gases such
as nitrogen as the carrier gas. Efficient conversion to hydrocarbon
fuel products were achieved by the processes described herein
because they produced a higher amount liquid hydrocarbon than
gaseous hydrocarbon at standard temperature and pressure.
Furthermore, the processes disclosed herein are
environment-friendly because the largest hydrocarbon by-product is
water.
[0025] In one aspect, provided herein is an unblended
cellulosic-biomass derived gasoline, wherein the unblended gasoline
has a research octane number of greater than about 87, as
determined by ASTM D2699. The unblended cellulosic-biomass derived
gasoline is the liquid produced by the process described herein
without further mixing or blending. And, in some embodiments, the
unblended cellulosic-biomass derived gasoline comprises a liquid
produced by the processes described herein, that has been further
distilled in the gasoline distillation range of 900 F to 4100 F. In
one embodiment, the unblended cellulosic-biomass derived gasoline
is generated by a process, which involves catalytic conversion.
[0026] In another aspect, provided herein is a method of producing
fuel comprising: receiving harvested cellulosic-biomass; treating
the cellulosic-biomass in a facility with an electron beam
sufficient to reduce its recalcitrance; saccharifying the
recalcitrance-reduced biomass to produce sugars and unsaccharified
biomass; fermenting the sugars to produce fuel; combusting the fuel
in a vehicle; generating heat and power from a portion of the
unsaccharified biomass in the facility and using the remaining
unprocessed unsaccharified biomass as animal feed; wherein the
method has a Global Warming Potential (GWP) in gCO.sub.2 eq/MJ at
least about 25% less in comparison to fuel generation from
starch-derived ethanol, sugar-derived ethanol or regular gasoline
mixture.
[0027] In one aspect, provided herein is a method for preparing
unblended cellulosic gasoline comprising: treating a
lignocellulosic biomass with a beam of electrons and saccharifying
the irradiated biomass to produce sugars; fermenting the sugars
with a microorganism to produce one or more alcohols; and
catalytically converting the one or more alcohols in a reactor into
a hydrocarbon mixture having a fraction boiling at a range of about
35.degree. C. to about 200.degree. C., thereby producing an
unblended cellulosic gasoline, wherein the unblended cellulosic
gasoline has an octane number of greater than 60 as determined by
ASTM D2699.
[0028] In one aspect, provided herein is a hydrocarbon fuel, such
as a gasoline, a diesel fuel or a jet fuel, having greater than 50
percent biogenic carbon, as measured using ASTM D6866-18. In some
embodiments, the hydrocarbon fuel, such as a blended or an
unblended fuel, is greater than 81 percent biogenic carbon, such as
greater than 82, 83, 84, 85, 86, 87 or higher, such as greater than
90, 91, 92, 95, 97, 98 or higher, such as greater than 99 percent.
The hydrocarbon fuel can be made, for example, by passing an
alcohol through a zeolite. In one aspect, the hydrocarbon fuel can
directly be used by different types of engines, such as a 2-cycle,
4-cycle, spark plug ignition, glow plug ignition, rotary engine,
high compression ignition engines, as well as car engines, prop
plane engines, jet engines, lawn mower engines, leaf blower
engines, or any other engines that can be configured to run on the
unblended cellulosic gasoline described herein.
[0029] In one aspect, provided herein is an E80/HOG fuel
composition made of about 80% cellulosic ethanol and about 20% of
cellulose-derived high-octane gasoline (HOG) in volume. The E80/HOG
has a biogenic carbon content of about 100%. According to certain
embodiments, less than about 0.01% of motor cleaning agent (such as
a deposit control additive) by volume is added to the E80/HOG fuel
composition before used in a commercial vehicle. In some
embodiments, the percentage is of the motor cleaning agent is much
lower than 0.01% such as about 0.002% by volume.
[0030] In one aspect, provided herein is a method for preparing the
cellulosic ethanol used in the E80/HOG fuel. The method of
preparation includes first treating ground corn cobs with electron
beam radiation and saccharifying the irradiated ground corn cob to
produce sugars. Then the sugars are fermented with active dry yeast
capable of generating ethanol.
[0031] Also provided is a method of producing cellulosic
biomass-derived jet fuel by the catalytic conversion of cellulosic
ethanol produced by the methods described herein over catalysts
such as the 0.5% Pt-0.25% Re/.gamma.-Al.sub.2O.sub.3 catalyst. In
one embodiment, the jet fuel contained about 25% of aromatic
hydrocarbons, about 2.5% of alkenes, about 41% of alkanes, and
about 8.5% of oxygenated compounds (wt./wt.).
[0032] In another aspect, provided herein is a method of generating
hydrocarbons from blends of ethanol with longer chain alcohols,
branched chain alcohols, esters, aldehydes and ketones. It has been
found that higher yields can be obtained if, in addition to
ethanol, higher alcohols, branched alcohols, esters and ketones are
blended into the ethanol, for example, using greater that about 5%
(w/w), 10% (w/w), 15% (w/w), 20% (w/w), 30% (w/w), 40% (w/w) or 50%
(w/w) of the longer chain alcohols, branched chain alcohols,
esters, aldehydes and ketones.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The invention is described with reference to the drawings,
which is presented for the purpose of illustration and in not
intended to be limiting of the invention, and in which:
[0034] FIG. 1 is a schematic block diagram illustrating the
conversion of biomass into products and co-products, including
biofuel, according to one or more embodiments.
[0035] FIG. 2 is a reaction scheme for converting a sugar to
butanol, ethanol, butyric acid, ethylbutyrate, which can be further
converted to fuel or other value-added products through one or more
processes.
[0036] FIG. 3A is a schematic block diagram illustrating the
conversion of alcohol derived from processed biomass to fuel blends
and other value-added products through dehydration and
hydrogenation.
[0037] FIG. 3B is a schematic block diagram illustrating the
conversion of oxygenates derived from biomass to fuel blends and
other value-added products through a reforming process in the
presence of reforming catalyst.
[0038] FIG. 4 is a schematic block diagram illustrating the
conversion of alcohol derived from processed biomass to fuel blends
and other value-added products through dehydrogenation and
deoxygenation.
[0039] FIG. 5 is a schematic block diagram illustrating the
conversion of biomass to biofuel through the aqueous phase
reforming/dehydration and dehydrogenation of polyols.
[0040] FIG. 6 is a schematic block diagram illustrating the
conversion of biomass to biofuel through the aqueous phase
reforming/dehydration and dehydrogenation of polyols, further
including the catalytic conversion of longer polyols to shorter
polyols.
[0041] FIG. 7 is a reaction scheme of converting processed biomass
to aromatic compounds.
[0042] FIG. 8A provides a schematic diagram of the longitudinal
section of a reactor (e.g., a trickle-bed reactor), in which a
catalytic conversion of biomass-derived building blocks takes
place. This diagram depicts an example where two catalysts,
Catalyst 1 and Catalyst 2, are in separate layers.
[0043] FIG. 8B provides a schematic diagram of the longitudinal
section of another reactor (e.g., a trickle-bed reactor), in which
catalytic conversion of biomass-derived building blocks takes
place. This diagram depicts an example where two catalysts,
Catalyst 1 and Catalyst 2 are blended together.
[0044] FIG. 8C provides a schematic diagram of the longitudinal
sections of two reactors (eg., trickle-bed reactors), in which
catalytic conversion of biomass-derived building blocks takes place
such that products and/or unreacted constituents from the first
reactor are directed into the second reactor for further catalytic
conversion. The first reactor has a catalyst bed made of Catalyst 1
and the second reactor has a catalyst bed made of Catalyst 2.
[0045] FIG. 9A provides a graphical description of the distribution
of hydrocarbons of various carbon content in the hydrocarbon
mixture that may be generated, and/or further processed during the
catalytic conversion of biomass-derived building blocks.
[0046] FIG. 9B provides a graphical description of the distribution
of hydrocarbons of various carbon content in the hydrocarbon
mixture that has been subjected to catalytic processing to convert
lower molecular hydrocarbons (typically gases) to higher molecular
weight hydrocarbons (typically liquid). The figure depicts an
example, where the hydrocarbon mixture contains a higher proportion
of higher molecular weight hydrocarbons as a result of the
catalytic processing of the hydrocarbon mixture.
[0047] FIG. 10 is a chromatogram obtained by analyzing ethanol
produced from lignocellulosic biomass generated by the processes
described in this application using Flame Ionization Detector (FID)
gas chromatography.
[0048] FIG. 11 provides a schematic block diagram illustrating the
conversion of biomass to various fuel, fuel-components, and other
value-added products.
[0049] FIG. 12A is a Flame Ionization Detector (FID) gas
chromatogram obtained by analyzing ethanol produced from
lignocellulosic biomass generated by the processes described in
this application. FIG. 12B shows a magnified version of the same
chromatogram.
[0050] FIG. 13A is a Flame Ionization Detector (FID) gas
chromatogram obtained by analyzing ethanol produced from cane. FIG.
13B shows a magnified version of the same chromatogram.
[0051] FIG. 14A is a Flame Ionization Detector (FID) gas
chromatogram obtained by analyzing ethanol produced from corn. FIG.
14B shows a magnified version of the same chromatogram.
[0052] FIG. 15A is a Flame Ionization Detector (FID) gas
chromatogram obtained by analyzing ethanol produce from grape. FIG.
15B shows a magnified version of the same chromatogram.
[0053] FIG. 16A is a Flame Ionization Detector (FID) gas
chromatogram obtained by analyzing ethanol produced from wheat.
FIG. 16B shows a magnified version of the same chromatogram.
[0054] FIG. 17A shows the element-profile of a fresh, unused
Pt-based catalyst. FIG. 17B is shows the element-profile of the
same catalyst after it has been used for catalytic conversion.
[0055] FIGS. 18A and 18A-2 provide a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of HZSM-5
catalyst, at a temperature of 350.degree. C., pressure of 500 psig
and volumetric linear flow rate (LFR) of 0.125 mL/min. The graph
shows the percentage amounts (vertical axis) of aromatics, alkenes,
alkanes and of oxygenates containing C2-C18 hydrocarbons
(horizontal axis) formed by the catalytic conversion of ethanol.
For example, the HZSM-5 catalyzed reaction produced hydrocarbons of
average carbon number 8.76, containing about 94.02% aromatics,
0.44% alkenes, 3.38% alkanes and 0.03% oxygenates as determined by
total ion chromatography peak area. FIGS. 18B and 18B-2 provide a
graphical description of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
hydrocarbon mixture generated by the catalytic processing of
biomass-derived ethanol produced by the processes described in this
application. The biomass-derived ethanol was converted to
hydrocarbons in the presence of 0.5% Ru/HZSM-5 catalyst, at a
temperature of 350.degree. C., pressure of 500 psig and volumetric
linear flow rate (LFR) of 0.125 mL/min. The resulting hydrocarbons
had an average carbon number of 8.57 and contained about 91.13% of
aromatics, 0.47% of alkenes, 5.87% of alkanes and 0.03% of
oxygenates as determined by total ion chromatography peak area.
FIGS. 18C and 18C-2 provides a graphical description of the product
distribution when the same reaction was run at a volumetric linear
flow rate (LFR) of 0.1875 mL/min. The resulting hydrocarbons had an
average carbon number of 7.78 and contained about 69.08% of
aromatics, 4.73% of alkenes, 22.94% of alkanes and 0.97% of
oxygenates as determined by total ion chromatography peak area.
[0056] FIGS. 19A and 19A-2 provide a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of 0.5%
Pt-0.5% Sn/Al.sub.2O.sub.3, at a temperature of 350.degree. C.,
pressure of 500 psig and volumetric linear flow rate (LFR) of 0.125
mL/min. The graph shows the percentage amounts (vertical axis) of
aromatics, alkenes, alkanes and of oxygenates containing C2-C18
hydrocarbons (horizontal axis) formed by the catalytic conversion
of ethanol. For example, the 0.5% Pt-0.5% Sn/Al.sub.2O.sub.3
catalyzed reaction produced hydrocarbons of average carbon number
9.2, containing about 44.16% aromatics, 0.51% alkenes, 32.32%
alkanes and 0.3% oxygenates as determined by total ion
chromatography peak area. FIGS. 19B and 19B-2 provide a graphical
description of the product distribution when the same reaction was
run at a volumetric linear flow rate (LFR) of 0.1875 mL/min. The
resulting hydrocarbons had an average carbon number of 7.11 and
contained about 25.59% of aromatics, 10.97% of alkenes, 53.03% of
alkanes and 0.86% of oxygenates, as determined by total ion
chromatography peak area.
[0057] FIGS. 20 and 20A provides a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of 0.5%
Pt-0.5% Bi/Al.sub.2O.sub.3, at a temperature of 350.degree. C.,
pressure of 500 psig and volumetric linear flow rate (LFR) of 0.125
mL/min. The graph shows the percentage amounts (vertical axis) of
aromatics, alkenes, alkanes and of oxygenates containing C2-C18
hydrocarbons (horizontal axis) formed by the catalytic conversion
of ethanol. For example, the 0.5% Pt-0.5% Bi/Al.sub.2O.sub.3
catalyzed reaction produced hydrocarbons of average carbon number
7.14, containing about 17.08% aromatics, 11.09% alkenes, 53.62%
alkanes and 6.66% oxygenates, as determined by total ion
chromatography peak area.
[0058] FIGS. 21A and 21A-2 provide a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of 0.5%
Pt-0.75% Ba/Al.sub.2O.sub.3, at a temperature of 350.degree. C.,
pressure of 500 psig and volumetric linear flow rate (LFR) of 0.125
mL/min. The graph shows the percentage amounts (vertical axis) of
aromatics, alkenes, alkanes and of oxygenates containing C2-C18
hydrocarbons (horizontal axis) formed by the catalytic conversion
of ethanol. For example, the 0.5% Pt-0.75% Ba/Al.sub.2O.sub.3
catalyzed reaction produced hydrocarbons of average carbon number
8.22, containing about 12.01% aromatics, 4.97% alkenes, 61.88%
alkanes and 15.70% oxygenates, as determined by total ion
chromatography peak area. FIGS. 21B and 21B-2 provide a graphical
description of the product distribution when the same reaction was
run with 0.5% Pt-1.0% Ba/Al.sub.2O.sub.3 catalyst. The resulting
hydrocarbons had an average carbon number of 7.72 and contained
about 7.87% of aromatics, 4.05% of alkenes, 76.53% of alkanes and
9.19% of oxygenates, as determined by total ion chromatography peak
area.
[0059] FIGS. 22A and 22A-2 provide a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of 0.5%
Pt-10% H.sub.3PO.sub.4--Al.sub.2O.sub.3, at a temperature of
350.degree. C., pressure of 300 psig and volumetric linear flow
rate (LFR) of 0.125 mL/min. The graph shows the percentage amounts
(vertical axis) of aromatics, alkenes, alkanes and of oxygenates
containing C2-C18 hydrocarbons (horizontal axis) formed by the
catalytic conversion of ethanol. For example, the 0.5% Pt-10%
H.sub.3PO.sub.4--Al.sub.2O.sub.3 catalyzed reaction produced
hydrocarbons of average carbon number 8.4, containing about 31.09%
aromatics, 3.84% alkenes, 48.64% alkanes and 0.41% oxygenates, as
determined by total ion chromatography peak area. FIGS. 22B and
22B-2 provides a graphical description of the product distribution
when the same reaction was run at a pressure of 500 psig. The
resulting hydrocarbons had an average carbon number of 9.66 and
contained about 39.53% of aromatics, 1.6% of alkenes, 45.10% of
alkanes and 0.30% of oxygenates, as determined by total ion
chromatography peak area. FIGS. 22C and 22C-2 provide a graphical
description of the product distribution when the same reaction was
run at a pressure of 700 psig. The resulting hydrocarbons had an
average carbon number of 8.80 and contained about 30.43% of
aromatics, 1.78% of alkenes, 47.27% of alkanes and 1.04% of
oxygenates, as determined by total ion chromatography peak
area.
[0060] FIGS. 23A and 23A-2 provide a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol produced by the
processes described in this application. The biomass-derived
ethanol was converted to hydrocarbons in the presence of 0.5%
Pt/5.0% H.sub.3BO.sub.3--Al.sub.2O.sub.3, at a temperature of
325.degree. C., pressure of 500 psig and volumetric linear flow
rate (LFR) of 0.125 mL/min. The graph shows the percentage amounts
(vertical axis) of aromatics, alkenes, alkanes and of oxygenates
containing C2-C18 hydrocarbons (horizontal axis) formed by the
catalytic conversion of ethanol. For example, the 0.5% Pt/5.0%
H.sub.3BO.sub.3--Al.sub.2O.sub.3 catalyzed reaction produced
hydrocarbons of average carbon number 7.2, containing about 4.67%
aromatics, 0.95% alkenes, 91.91% alkanes and 0.05% oxygenates, as
determined by total ion chromatography peak area. FIGS. 23B, 23B-2,
23C, 23C-2, 23D, and 23D-2 provide a graphical description of the
product distribution when the same reaction was run at a
temperature of 350.degree. C., and at a pressure of 300 psig, 500
psig, and 700 psig, respectively. When the reaction was run at a
temperature of 350.degree. C., and at a pressure of 300 psig, the
resulting hydrocarbons had an average carbon number of 7.7, and
contained about 19.24% of aromatics, 1.32% of alkenes, 73.01% of
alkanes and 0.31% of oxygenates, as determined by total ion
chromatography peak area. When the reaction was run at a
temperature of 350.degree. C., and at a pressure of 500 psig, the
resulting hydrocarbons had an average carbon number of 8.77, and
contained about 19.35% of aromatics, 0.24% of alkenes, 64.81% of
alkanes and 4.93% of oxygenates, as determined by total ion
chromatography peak area. When the reaction was run at a
temperature of 350.degree. C., and at a pressure of 700 psig, the
resulting hydrocarbons had an average carbon number of 8.17, and
contained about 10.42% of aromatics, 1.37% of alkenes, 81.65% of
alkanes and 0.88% of oxygenates, as determined by total ion
chromatography peak area.
[0061] FIG. 24 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in a standard gasoline sample. A standard
gasoline sample was found to contain hydrocarbons with an average
carbon number of 7.47, and about 45.54% aromatics, 4.00% alkenes,
43.53% of alkanes and 4.20% of oxygenates, as determined by total
ion chromatography peak area.
[0062] FIGS. 25 and 25A provides a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol when it is
catalytically converted to hydrocarbons in the presence of 0.5%
Pt-0.5% Sn-0.5% Bi/Al.sub.2O.sub.3, at a temperature of 350.degree.
C., pressure of 500 psig and volumetric linear flow rate (LFR) of
0.125 mL/min. The graph shows the percentage amounts (vertical
axis) of aromatics, alkenes, alkanes and of oxygenates containing
C2-C18 hydrocarbons (horizontal axis) formed by the catalytic
conversion of ethanol. The reaction produced hydrocarbons of
average carbon number 8.25, containing about 30.51% aromatics,
5.29% alkenes, 39.35% alkanes and 3.43% oxygenates, as determined
by total ion chromatography peak area.
[0063] FIGS. 26 and 26A provides a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol when it is
catalytically converted to hydrocarbons in the presence of 0.5%
Pt-0.5% Sn-0.5% Re/Al.sub.2O.sub.3, at a temperature of 350.degree.
C., pressure of 500 psig and volumetric linear flow rate (LFR) of
0.125 mL/min. The graph shows the percentage amounts (vertical
axis) of aromatics, alkenes, alkanes and of oxygenates containing
C2-C18 hydrocarbons (horizontal axis) formed by the catalytic
conversion of ethanol. The reaction produced hydrocarbons of
average carbon number 8.19, containing about 31.47% aromatics,
14.34% alkenes, 31.87% alkanes and 1.53% oxygenates, as determined
by total ion chromatography peak area.
[0064] FIG. 27 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in the high-octane hydrocarbon distillate or
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein.
[0065] FIG. 28 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in the low-octane hydrocarbon distillate or
low-octane gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein.
[0066] FIG. 29 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C1, which contains Trufuel.RTM., a
commercially available premixed high-octane ethanol-free fuel.
[0067] FIG. 30 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C2, which is a mixture of about
50% (v/v) of high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein, and about
50% (v/v) of Trufuel.RTM..
[0068] FIG. 31 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C3, which is a mixture of about
85% (v/v) of high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein, and about
15% (v/v) of Trufuel.RTM..
[0069] FIG. 32 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C4, which is a mixture of about
70% (v/v) of high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein, and about
30% (v/v) of low-octane gasoline (LOG), generated by the catalytic
processing of biomass-derived ethanol described herein.
[0070] FIG. 33 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C5, which is a mixture of about
65% (v/v) of high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein, about 25%
(v/v) of low-octane gasoline (LOG), generated by the catalytic
processing of biomass-derived ethanol described herein, and about
10% of anhydrous ethanol derived from cellulosic-biomass.
[0071] FIG. 34 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample C6, which is a mixture of about
90% (v/v) of high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein, and about
10% of anhydrous ethanol derived from cellulosic-biomass.
[0072] FIG. 35 provides the results of analyzing samples of blends
of high-octane gasoline of samples C1-C6, described above. The API
Gravity @ 60.degree. F. is measured according to ASTM D4052, the
Dry Vapor Pressure Equivalent (DVPE) EPA is measured according to
ASTM D5191-13, the gross heat of combustion is measured according
to ASTM D4809, the research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, and the antiknock index or octane rating
((RON+MON)/2) is measured according to D4814-X1.4.
[0073] FIG. 36 provides the results of analyzing samples of blends
of high-octane gasoline. Sample B1 is Trufuel.RTM.; sample B2 is a
mixture of 5% (v/v) of high-octane gasoline (HOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 95% (v/v) of Trufuel.RTM.; sample B3 is a mixture of 10% (v/v)
of high-octane gasoline (HOG) generated by the catalytic processing
of biomass-derived ethanol described herein, and 90% (v/v) of
Trufuel.RTM.; sample B4 is a mixture of 20% (v/v) of high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and 80% (v/v) of
Trufuel.RTM.; sample B5 is a mixture of 20% (v/v) of high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, 75% (v/v) of
Trufuel.RTM., and 5% anhydrous ethanol derived from
cellulosic-biomass. The Dry Vapor Pressure Equivalent (DVPE) EPA is
measured according to ASTM D5191, the gross heat of combustion is
measured according to ASTM D4809, the research octane number (RON)
is measured according to ASTM D2699, the motor octane number (MON)
is measured according to ASTM D2700, and the antiknock index or
octane rating ((RON+MON)/2) is measured according to
D4814-X1.4.
[0074] FIG. 37 provides the results of analyzing samples of blends
of low-octane gasoline. Sample 1 is Trufuel.RTM., a commercially
available premixed high-octane ethanol-free fuel; sample 2 is a
mixture of 5% (v/v) of low-octane gasoline (LOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 95% (v/v) of Trufuel.RTM.; sample 3 is a mixture of 10% (v/v)
of low-octane gasoline (LOG) generated by the catalytic processing
of biomass-derived ethanol described herein, and 90% (v/v) of
Trufuel.RTM.; sample 4 is a mixture of 20% (v/v) of low-octane
gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and 80% (v/v) of
Trufuel.RTM.; sample 5 is a mixture of 20% (v/v) of low-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, 75% (v/v) of
Trufuel.RTM., and 5% anhydrous ethanol derived from
cellulosic-biomass. The research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, and the antiknock index or octane rating
((RON+MON)/2) is measured according to D4814-X1.4.
[0075] FIG. 38 provides a Life Cycle Assessment (LCA) evaluating
the Global Warming Potential (GWP) of fuel blends containing
ethanol generated from cellulosic-biomass by the processes
described herein with US corn grain ethanol, Brazilian sugarcane
ethanol and US conventional gasoline. Fuel blends of 100% ethanol
(E100) (98.5% ethanol with 2.5% gasoline for denaturing purposes as
required by the law), 10% ethanol (E10), 85% ethanol (E85), and
conventional gasoline were compared.
[0076] FIG. 39 provides a diagram of the process for generating
ethanol from cellulosic-biomass from cradle-to-grave, which formed
the basis of the LCA analysis shown in FIG. 38.
[0077] FIG. 40 describes the compositions (volume %) of samples D1
to D6. Sample D1 is 100% Trufuel.RTM.; sample D2 is a mixture of
90% (v/v) high-octane gasoline (HOG) (Fraction 2b) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 10% (v/v) of ethanol; sample D3 is 100% (v/v) high-octane
gasoline (HOG) (Fractions 1b and 2b) generated by the catalytic
processing of biomass-derived ethanol described herein; sample D4
is 100% (v/v) high-octane gasoline (HOG) (Fraction 2b) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample D5 is 100% (v/v) of high-octane gasoline (HOG) (all
fractions) generated by the catalytic processing of biomass-derived
ethanol described herein; sample D6 is a mixture of 50% (v/v)
low-octane gasoline (LOG) (Fractions 1a and 2a) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 50% (v/v) of ethanol. Fraction 1 is a portion of the HOG or LOG
that has a boiling range below 30.degree. C. ("low boiling range
fractions"), Fraction 2 is a portion of the HOG or LOG that has a
boiling range between 35 to 200.degree. C. ("mid boiling range
fractions"), and Fraction 3 is a portion of the HOG or LOG that has
a boiling range above 200.degree. C. ("high boiling range
fraction"). Letters "a" and "b" distinguishes the fractions from
the HOG from the fractions from the LOG. For example, Fraction 1a
represents low boiling range fractions from the LOG, while Fraction
1b represents low boiling range fractions from the HOG.
[0078] FIG. 41 shows the volume percentages and the weight
percentages of the fractions within one or more samples described
in FIG. 40. FIG. 41 shows that sample D3 is a HOG with about 13.06%
(v/v) of Fraction 1b, and about 86.93% (v/v) of Fraction 2b. It
also has about 11.89 wt. % of Fraction 1, and about 88.10 wt. % of
Fraction 2. Sample D5 is a HOG with about 14.30% (v/v) of Fraction
1, about 93.29% (v/v) of Fraction 2, and about 2.40% (v/v) of
Fraction 3. It also has about 11.97 wt. % of Fraction 1, about
85.22 wt. % of Fraction 2, and about 2.70 wt. % of Fraction 3.
Lastly, Sample D6 is a LOG with about 12.56% (v/v) of Fraction 1,
about 74.89% (v/v) of Fraction 2, and about 4.68% (v/v) of Fraction
3. In addition, it has about 18.61 wt. % of Fraction 1, about 75.71
wt. % of Fraction 2, and about 5.67 wt. % of Fraction 3.
[0079] FIG. 42 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D1, which contains Trufuel.RTM., a
commercially available premixed high-octane ethanol-free fuel.
[0080] FIG. 43 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D2, which is a mixture of about
90% (v/v) of Fraction 2b distilled from the high-octane gasoline
(HOG) generated by the catalytic processing of biomass-derived
ethanol described herein, and about 10% (v/v) of biomass-derived
ethanol.
[0081] FIG. 44 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D3, which contains 100% (v/v) of
Fraction 1b and Fraction 2b of the high-octane gasoline (HOG)
generated by the catalytic processing of biomass-derived ethanol
described herein.
[0082] FIG. 45 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D4, which contains 100% (v/v) of
Fraction 2b of the high-octane gasoline (HOG) generated by the
catalytic processing of biomass-derived ethanol described
herein.
[0083] FIG. 46 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D5, which contains 100% (v/v) of
the high-octane gasoline (HOG) generated by the catalytic
processing of biomass-derived ethanol described herein without
further distillation.
[0084] FIG. 47 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in sample D6, which is a mixture of about
50% (v/v) of fractions 1a and 2a distilled from the low-octane
gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and about 50% (v/v) of
biomass-derived ethanol.
[0085] FIG. 48 provides the results of analyzing samples of blends
of high-octane gasoline of samples D1-D6, described above. The API
Gravity @ 60.degree. F. is measured according to ASTM D4052, the
Dry Vapor Pressure Equivalent (DVPE) EPA is measured according to
ASTM D5191-13, the gross heat of combustion is measured according
to ASTM D4809, the research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, the sulfur content is measured according
to ASTM D7039, the benzene content is measured according to ASTM
D3606, the odor is measured according to ASTM D1296, the water
content is measured according to ASTM E1064, the corrosion to
copper strips is measured according to ASTM D130, and the corrosion
to silver strips is measured according to ASTM D4814-A1, and the
antiknock index or octane rating ((RON+MON)/2) is measured
according to D4814-X1.4.
[0086] FIG. 49 describes the compositions (volume %) of samples E1
to E8. Sample E1 is 100% high-octane gasoline (HOG) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample E2 is 100% low-octane gasoline (LOG) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample E3 is 100% cellulosic ethanol generated by the
process described herein; sample E4 is a mixture of 95% HOG with 5%
of cellulosic ethanol, derived by the process described herein;
sample E5 is a mixture of 95% LOG with 5% of cellulosic ethanol,
derived by the process described herein; sample E6 is a
commercially available gasoline--Trufuel.RTM.; sample E7 is a
mixture of 50% HOG with 50% Trufuel.RTM.; sample E8 is a mixture of
50% cellulosic ethanol, derived by the process described herein,
with 50% Trufuel.RTM..
[0087] FIG. 50 describes the % biogenic carbon content for samples
E1 to E8 as determined by ASTM D6866-18. Samples E1-E5 all have
about 100% biogenic carbon content (as a fraction of total carbon).
Specifically, sample E1 has about 103.17 pMC; sample E2 has about
101.98 pMC; sample E3 has about 102.72 pMC; sample E4 has about
102.45 pMC; sample E5 has about 102.40 pMC. Sample E6, 100%
Trufuel.RTM., has about 0% biogenic carbon content (as a fraction
of total carbon), and about 100% of fossil carbon content.
Specifically, sample E6 has less than 0.44 pMC. Sample E7 has about
62% biogenic carbon content (as a fraction of total carbon), and
about 38% of fossil carbon. Specifically, sample E7 has about 62.59
pMC. Lastly, sample E8 has about 44% biogenic carbon content (as a
fraction of total carbon), and about 56% of fossil carbon.
Specifically, sample E8 has about 44.40 pMC.
[0088] FIG. 51 provides a graphical depiction of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in the jet fuel generated by the catalytic
processing of biomass-derived ethanol described herein. Based on
the total known components, the jet fuel contained about 25% of
aromatic hydrocarbons, about 2.5% of alkenes, about 41% of alkanes,
and about 8.5% of oxygenated compounds (wt./wt.).
[0089] FIG. 52 provides a graphical description of the product
distribution of aromatics, alkenes, alkanes and oxygenates of
various carbon content in the hydrocarbon mixture generated by the
catalytic conversion of a composition of acetone, butanol and
ethanol (ABE). The graph shows the percentage amounts (vertical
axis) of aromatics, alkenes, alkanes and of oxygenates containing
C2-C18 hydrocarbons (horizontal axis) formed by the catalytic
conversion of ABE. The resulting hydrocarbon contained about 82.5%
of aromatics, 2.9% alkenes, 12.48% alkanes, and 7% of other
compounds, included oxygenated species.
DETAILED DESCRIPTION
[0090] Carbon-containing materials, such as biomass (e.g., plant
biomass, animal biomass, and municipal waste biomass) or coal can
be processed to a lower level of recalcitrance (if necessary) and
converted into intermediates and products such as those listed by
way of examples herein. These intermediate compounds can be further
processed into useful products, including fuels. Other products and
co-products that can be produced include, for example, human food,
animal feed, pharmaceuticals, chemicals, plastics and
nutraceuticals.
[0091] In one aspect, biomass (e.g., plant biomass, such as those
that are or that include one or more low molecular weight sugars,
animal biomass, and municipal waste biomass) can be processed to
produce useful products such as fuels, e.g., fuels for internal
combustion engines, jet engines or feedstocks for fuel cells and
for heating oil. Systems and processes are described herein that
can use various biomass materials, such as cellulosic materials,
lignocellulosic materials, starchy materials or materials that are
or that include low molecular weight sugars, as feedstock
materials. Such materials are often readily available, but can be
difficult to process, e.g., by fermentation, or can give
sub-optimal yields at a slow rate. Feedstock materials are first
physically prepared for processing, often by size reduction of raw
feedstock materials. Physically prepared feedstock can be
pretreated or processed using one or more of radiation, sonication,
oxidation, pyrolysis, and steam explosion. The feedstock materials
can be further processed into sugars, e.g., monosaccharides,
disaccharides or other low molecular weight sugars, that can be
converted by a microorganism into intermediates that are useful
building blocks to fuels. The various pretreatment systems and
methods can be used in combinations of two, three, or even four of
these technologies.
[0092] In some cases, feedstocks that include one or more
saccharide units or saccharide derivative units can be treated by
any one or more of the processes described herein A saccharide unit
as used herein is meant a sugar including monosaccharide,
disaccharide, and oligosaccharide sugars. Examples of
monosaccharides include glucose (dextrose), fructose, galactose,
and ribose. Examples of disaccharides include sucrose and
cellobiose. A saccharide derivative unit as used herein is a
compound obtained by chemical modification or bioprocessing of a
sugar unit, and can include fermentation using microorganisms.
Aviation Fuel
[0093] In some embodiments, the final product generated by the
invention is aviation gasoline or "avgas." The avgas produced by
this invention can be used in various suitable aircrafts, including
in aircrafts containing spark-ignited internal-combustion engines.
The avgas can consist of chemical blends of hydrocarbons, and
additives such as antioxidants and metal deactivators, and fuel
dyes. In addition to hydrocarbons such as n-heptanes and
isooctanes, avgas can also contain unsaturated hydrocarbons such as
olefins, naphthalenes, xylene, mesitylene, and other aromatics, one
or more of which are derived from biomass.
[0094] The amount of aromatics can vary in the avgas. In some
embodiments, Avgas can have 90% or less aromatics, 80% or less
aromatics by volume, 70% or less aromatics by volume, 60% or less
aromatics by volume, 50% or less aromatics by volume, 40% or less
aromatics by volume, 30% or less aromatics by volume, 20% or less
aromatics by volume, or 10% or less aromatics by volume. The
preferred range for aromatic content in avgas may be 25% or less,
by volume. In some embodiments, avgas is limited to monoaromatics
by distillation requirements. In some embodiments, toluene is the
only aromatic compound in avgas.
[0095] In some embodiments, the avgas contains about 100% pure
isooctane, about 95% pure isooctane, about 90% pure isooctane,
about 85% pure isooctane, about 80% pure isooctane, about 75% pure
isooctane, about 70% pure isooctane, about 65% pure isooctane,
about 60% pure isooctane, about 55% pure isooctane, about 50% pure
isooctane, about 40% pure isooctane, about 35%, about 30% pure
isooctane, about 25% pure isooctane, about 20% pure isooctane,
about 15% pure isooctane, about 10% pure isooctane, about 5% pure
isooctane. Higher isooctane content (and lower corresponding
n-heptane content) is often correlated with a higher octane rating,
and hence, preferred.
[0096] In some embodiments, the avgas contains about 95% pure
n-heptane, about 90% pure n-heptane, about 85% pure n-heptane,
about 80% pure n-heptane, about 75% pure n-heptane, about 70% pure
n-heptane, about 65% pure n-heptane, about 60% pure n-heptane,
about 55% pure n-heptane, about 50% pure n-heptane, about 40% pure
n-heptane, about 35%, about 30% pure n-heptane, about 25% pure
n-heptane, about 20% pure n-heptane, about 15% pure n-heptane,
about 10% pure n-heptane, and about 5% pure n-heptane.
[0097] In some embodiments, the avgas can include tetra-ethyl lead,
which can potentially improve the anti-knock capabilities of avgas.
For example, the avgas produced by this invention can be
characterized by varying amounts of lead content, including
unleaded avgas, low lead avgas and avgas with high lead
content.
[0098] The avgas produced by this invention can be of various
grades, including different Motor Octane Numbers (MON). In one
embodiment, the avgas may have a MON of 100/130, that is 100-octane
fuel (or lean setting, usually used for cruising) and a rich
setting of 130 (which may be used for take-off and other full-power
conditions). Avgas of various grades such as 80/87, 91/96, 91/115,
115/145, 108/135, 82UL, 85UL, 91/96UL, and 100LL may also be
produced by this invention, wherein UL refers to unleaded avgas and
LL refers to low-lead avgas.
[0099] In some embodiments, the avgas can have a minimum smoke
point of about 30 mm, about 28 mm, about 26 mm, about 25 mm, about
24 mm, about 22 mm, about 20 mm, about 19 mm, about 18 mm, about 16
mm, and about 15 mm.
[0100] The avgas produced by this invention can have a range of
density, viscosity, freezing point, volatility and flash point. See
Aviation Fuel: Technology Review (2007), available at
https://www.cgabusinessdesk.com/document/aviation_tech_review.pdf.
Biojet Fuel
[0101] One of the products that can be produced by this invention
is jet fuel. The jet fuel produced by the processes described
herein can be used in any aircraft or automotive that is powered by
a piston engine, compression ignition engine, or a gas-turbine
engine (such as a jet engine, a turboprop engine, aeroderivative
gas turbine, turboshaft engine and scale jet engine).
[0102] The jet fuel produced by this invention can be a mixture of
a large number of different hydrocarbons, such as linear or
branched, mono-, and di-substituted C.sub.7-C.sub.16 alkanes, one
or more of which is derived from biomass. It may also contain
olefins, substituted or unsubstituted cycloalkanes (such as
cyclopentanes, cyclohexanes), aromatics (such as benzene, toluene,
naphthalenes), mono-substituted aromatics (such as methyl benzene),
di-substituted aromatics (such as xylenes), and multi-substituted
aromatics (such as trimethylbenzenes), one or more of which is
derived from biomass. See
https://www.atsdr.cdc.gov/ToxProfiles/tp76-c3.pdf. The jet fuel may
further contain nonhydrocarbon compounds such as sulfur compounds,
anti-knock additives (such as tetra-ethyl lead), antioxidants,
metal deactivators, fuel system icing inhibitors, corrosion
inhibitors, and static dissipator additives. Some embodiments may
also include combustible oxygen containing components such as
esters, and ethers.
[0103] In some embodiments, the jet fuel can have about 100-95%
saturated hydrocarbons, about 94-90% saturated hydrocarbons, about
89-85% saturated hydrocarbons, about 84-80% saturated hydrocarbons,
about 79-75% saturated hydrocarbons, about 74-70% saturated
hydrocarbons, about 69-65% saturated hydrocarbons, about 64-60%
saturated hydrocarbons, about 59-55% saturated hydrocarbons, about
54-50% saturated hydrocarbons, about 49-45% saturated hydrocarbons,
about 44-40% saturated hydrocarbons, about 39-35% saturated
hydrocarbons, about 34-30% saturated hydrocarbons, about 29-25%
saturated hydrocarbons, about 24-20% saturated hydrocarbons, about
19-15% saturated hydrocarbons, about 14-10% saturated hydrocarbons,
about 9-5% saturated hydrocarbons, and about 4-0% saturated
hydrocarbons.
[0104] In some embodiments, the jet fuel can have about 100-95%
aromatic hydrocarbons, about 94-90% aromatic hydrocarbons, about
89-85% aromatic hydrocarbons, about 84-80% aromatic hydrocarbons,
about 79-75% aromatic hydrocarbons, about 74-70% aromatic
hydrocarbons, about 69-65% aromatic hydrocarbons, about 64-60%
aromatic hydrocarbons, about 59-55% aromatic hydrocarbons, about
54-50% aromatic hydrocarbons, about 49-45% aromatic hydrocarbons,
about 44-40% aromatic hydrocarbons, about 39-35% aromatic
hydrocarbons, about 34-30% aromatic hydrocarbons, about 29-25%
aromatic hydrocarbons, about 24-20% aromatic hydrocarbons, about
19-15% aromatic hydrocarbons, about 14-10% aromatic hydrocarbons,
about 9-5% aromatic hydrocarbons, and about 4-0% aromatic
hydrocarbons.
[0105] In some embodiments, the jet fuel can have about 100-95%
olefin hydrocarbons, about 94-90% olefin hydrocarbons, about 89-85%
olefin hydrocarbons, about 84-80% olefin hydrocarbons, about 79-75%
olefin hydrocarbons, about 74-70% olefin hydrocarbons, about 69-65%
olefin hydrocarbons, about 64-60% olefin hydrocarbons, about 59-55%
olefin hydrocarbons, about 54-50% olefin hydrocarbons, about 49-45%
olefin hydrocarbons, about 44-40% olefin hydrocarbons, about 39-35%
olefin hydrocarbons, about 34-30% olefin hydrocarbons, about 29-25%
olefin hydrocarbons, about 24-20% olefin hydrocarbons, about 19-15%
olefin hydrocarbons, about 14-10% olefin hydrocarbons, about 9-5%
olefin hydrocarbons, and about 4-0% olefin hydrocarbons.
[0106] In one embodiment, the jet fuel may contain 70-85% saturated
hydrocarbon, less than 25% aromatic hydrocarbon and less than 5%
olefin hydrocarbon. In some embodiments, the jet fuel can have
octane rating in the range of 15-25.
[0107] The jet fuel produced by this invention can be used in both
civilian and military aircrafts. For example, civilian aircrafts
may use jet fuels of the type Jet A, Jet A-1 and Jet-B. Jet A-1 is
a kerosene grade fuel suitable for most turbine engines and has a
flash point of 38.degree. C. and a freezing point of -47.degree. C.
Jet A-1 can have 18-25% aromatics and up to 5% olefins by volume.
Jet A is a high-purity kerosene-based fuel that has the same flash
point and aromatics composition as Jet A-1, but has a higher
freezing point, -40.degree. C. Jet B is a distillate covering the
naphtha and kerosene fractions, and has a low flash point (between
-23 and -1.degree. C.). Jet A-1, Jet A, and Jet B are required to
have a minimum smoke point of 25 mm, or 18 mm if they are composed
of less than or equal to 3% naphthalene by volume.
[0108] The jet fuel developed by this invention can also be
military grade jet fuel such as JP-1, JP-2, JP-3, JP-4, JP-5, JP-6,
JP-7, JP-8, JP-9, JP-10 and JPTS. For example, JP-8 is the military
equivalent of Jet A-1 with the addition of a military fuel additive
(such as static dissipater, corrosion inhibitor, lubricity
improver, fuel system icing inhibitor, antioxidant and metal
deactivators). JP-8 has a freezing point of -47.degree. C. and a
flash point of 38.degree. C. JP-8 is required to have a minimum
smoke point of 25 mm, or 19 mm if it is composed of 3% or less
naphthalene by volume. JP-8 is also required to have a hydrogen
content of at least 13.4% by mass. JP-8 can have 0.1-25% aromatics
by liquid volume. JP-4 has a freezing point of -46.degree. C. and a
flash point between -23 and -1.degree. C. JP-4 can have 10%
aromatics by volume. JP-5 is a kerosene-based fuel that has a
freezing point of -46.degree. C. and a flash point of 60.degree. C.
JP-5 can have 19% aromatics by volume. JP-7 is a mixture composed
primarily of hydrocarbons, and has a freezing point of -30.degree.
C. and a flash point of 60.degree. C. JP-7 can have 3% aromatics by
volume. JPTS or Jet Propellant Thermally Stable fuel has a freezing
point of -53.degree. C. and a flash point of 43.degree. C.
Diesel
[0109] In some embodiments, the fuel produced by the processes
described in this application is diesel. The diesel fuel can be
made of a mixture of hydrocarbons, such as C8-C22 hydrocarbons,
aromatic hydrocarbons and some olefin hydrocarbons, one or more of
which is derived from biomass. Additionally, additives such as
Alkyl nitrates (e.g., 2-ethylhexyl nitrate) and di-tert-butyl
peroxide may be used to raise the cetane number. The cetane number
is an indicator of the combustion speed of diesel.
[0110] In some embodiments, the diesel fuel can have about 100-95%
saturated hydrocarbons, about 94-90% saturated hydrocarbons, about
89-85% saturated hydrocarbons, about 84-80% saturated hydrocarbons,
about 79-75% saturated hydrocarbons, about 74-70% saturated
hydrocarbons, about 69-65% saturated hydrocarbons, about 64-60%
saturated hydrocarbons, about 59-55% saturated hydrocarbons, about
54-50% saturated hydrocarbons, about 49-45% saturated hydrocarbons,
about 44-40% saturated hydrocarbons, about 39-35% saturated
hydrocarbons, about 34-30% saturated hydrocarbons, about 29-25%
saturated hydrocarbons, about 24-20% saturated hydrocarbons, about
19-15% saturated hydrocarbons, about 14-10% saturated hydrocarbons,
about 9-5% saturated hydrocarbons, about 4-0% saturated
hydrocarbons.
[0111] In some embodiments, the diesel fuel can have about 100-95%
aromatic hydrocarbons, about 94-90% aromatic hydrocarbons, about
89-85% aromatic hydrocarbons, about 84-80% aromatic hydrocarbons,
about 79-75% aromatic hydrocarbons, about 74-70% aromatic
hydrocarbons, about 69-65% aromatic hydrocarbons, about 64-60%
aromatic hydrocarbons, about 59-55% aromatic hydrocarbons, about
54-50% aromatic hydrocarbons, about 49-45% aromatic hydrocarbons,
about 44-40% aromatic hydrocarbons, about 39-35% aromatic
hydrocarbons, about 34-30% aromatic hydrocarbons, about 29-25%
aromatic hydrocarbons, about 24-20% aromatic hydrocarbons, about
19-15% aromatic hydrocarbons, about 14-10% aromatic hydrocarbons,
about 9-5% aromatic hydrocarbons, and about 4-0% aromatic
hydrocarbons.
[0112] In some embodiments, the diesel can have about 50-45% olefin
hydrocarbons, about 44-40% olefin hydrocarbons, about 39-35% olefin
hydrocarbons, about 34-30% olefin hydrocarbons, about 29-25% olefin
hydrocarbons, about 24-20% olefin hydrocarbons, about 19-15% olefin
hydrocarbons, about 14-10% olefin hydrocarbons, about 9-5% olefin
hydrocarbons, and about 4-0% olefin hydrocarbons.
[0113] In one embodiment, diesel may contain about 75% saturated
hydrocarbon, and about 25% aromatic hydrocarbon. In a preferred
embodiment, the diesel can have 10% or less aromatic compounds.
[0114] The boiling points of the diesel fuel generated by this
invention can be in the range of 150 to 380.degree. C.
[0115] In some embodiments, the diesel can be a biodiesel, which
contains long-chain alkyl esters. For example, biodiesel can be
generated by reacting naturally-occurring fatty acids with alcohols
generated by fermentation of biomass to produce fatty acid esters.
For example, fatty-acid methyl ester (FAME) can be produced by
transesterification of fatty acids with methanol. The biodiesel
produced by the invention can be used in various biodiesel blends
with conventional hydrocarbon-based diesels and is often
characterized by their B-factor. For example, 100% biodiesel is
referred to as B100, 20% biodiesel, 80% petrodiesel blend is
labeled B20, 5% biodiesel, 95% petrodiesel blend is labeled B5, and
2% biodiesel, 98% petrodiesel is labeled as B2.
[0116] The diesel produced by this invention can be of any standard
diesel fuel grades--Nos. 1-D, 2-D, 4-D--numbered by increasing
density and viscosity. For example, 1-D and 2-D grade diesel fuel
are used to power diesel automobiles and railroad cars. 4-D is
often used to power marine vessels.
[0117] In some embodiments, the diesel produced by this invention
may have a cetane number (CN) of about 100-95, about 94-90, about
89-80, about 84-80, about 79-75, about 74-70, about 69-65, about
64-60, about 59-55, about 54-50, about 49-45, about 44-40, about
39-35, about 34-30, about 29-25, about 24-20, about 19-15, about
14-10, and about 9-5. The diesel fuel produced by this invention
can also be optimized for its density, lubricity, cold-flow
properties and sulfur content.
Kerosene
[0118] Kerosene can also be produced by the processes described in
this invention. The kerosene produced by this invention can consist
of straight and branched-chain alkanes containing about 6-16 carbon
atoms per molecule, and aromatic compounds and olefins, one or more
of which are derived from biomass.
[0119] In some embodiments, the kerosene can have about 100-95%
saturated hydrocarbons, about 94-90% saturated hydrocarbons, about
89-85% saturated hydrocarbons, about 84-80% saturated hydrocarbons,
about 79-75% saturated hydrocarbons, about 74-70% saturated
hydrocarbons, about 69-65% saturated hydrocarbons, about 64-60%
saturated hydrocarbons, about 59-55% saturated hydrocarbons, about
54-50% saturated hydrocarbons, about 49-45% saturated hydrocarbons,
about 44-40% saturated hydrocarbons, about 39-35% saturated
hydrocarbons, about 34-30% saturated hydrocarbons, about 29-25%
saturated hydrocarbons, about 24-20% saturated hydrocarbons, about
19-15% saturated hydrocarbons, about 14-10% saturated hydrocarbons,
about 9-5% saturated hydrocarbons, and about 4-0% saturated
hydrocarbons.
[0120] In some embodiments, the kerosene can have about 100-95%
aromatic hydrocarbons, about 94-90% aromatic hydrocarbons, about
89-85% aromatic hydrocarbons, about 84-80% aromatic hydrocarbons,
about 79-75% aromatic hydrocarbons, about 74-70% aromatic
hydrocarbons, about 69-65% aromatic hydrocarbons, about 64-60%
aromatic hydrocarbons, about 59-55% aromatic hydrocarbons, about
54-50% aromatic hydrocarbons, about 49-45% aromatic hydrocarbons,
about 44-40% aromatic hydrocarbons, about 39-35% aromatic
hydrocarbons, about 34-30% aromatic hydrocarbons, about 29-25%
aromatic hydrocarbons, about 24-20% aromatic hydrocarbons, about
19-15% aromatic hydrocarbons, about 14-10% aromatic hydrocarbons,
about 9-5% aromatic hydrocarbons, and about 4-0% aromatic
hydrocarbons.
[0121] In some embodiments, the kerosene can have about 100-95%
olefin hydrocarbons, about 94-90% olefin hydrocarbons, about 89-85%
olefin hydrocarbons, about 84-80% olefin hydrocarbons, about 79-75%
olefin hydrocarbons, about 74-70% olefin hydrocarbons, about 69-65%
olefin hydrocarbons, about 64-60% olefin hydrocarbons, about 59-55%
olefin hydrocarbons, about 54-50% olefin hydrocarbons, about 49-45%
olefin hydrocarbons, about 44-40% olefin hydrocarbons, about 39-35%
olefin hydrocarbons, about 34-30% olefin hydrocarbons, about 29-25%
olefin hydrocarbons, about 24-20% olefin hydrocarbons, about 19-15%
olefin hydrocarbons, about 14-10% olefin hydrocarbons, about 9-5%
olefin hydrocarbons, and about 4-0% olefin hydrocarbons.
[0122] In one embodiment, the kerosene may contain about 70%
saturated hydrocarbon, less than 25% aromatic hydrocarbon and less
than 5% olefin hydrocarbon.
[0123] The kerosene produced by the methods described herein can be
of 1-K grade, which is a cleaner kerosene that burns with fewer
deposits or toxins, or 2-K grade, which can be used for indoor
kerosene heaters and stoves. The kerosene can have a boiling point
of 150.degree. C. to 300.degree. C., a density of 0.78-0.81
g/cm.sup.3, and a flash point between 37 and 65.degree. C., a smoke
point between 17-25 mm, an octane rating of 15-25 Anti-knock Index
(AKI).
Gasoline
[0124] The processes described by the application can also be used
to produce gasoline. The gasoline can consist of branched and
straight-chain hydrocarbons with 4 to 12 carbon atoms per molecule
(such as propane, isobutene, n-butane, n-pentane, n-hexane,
methyl-alkanes, dimethyl-alkanes), substituted and un-substituted
aromatic compounds (such as xylene, toluene, naphthalene) and
olefins (such as butane, pentene), one or more of which are derived
from biomass. See
http://bcn.boulder.co.us/basin/waterworks/gasolinecomp.pdf.
Additives may include oxygenates such as alcohol and ethers,
antioxidants (such as butylated hydroxytoluene), antiknock agents
(such as tetraethyllead, isooctane, toluene), lead scavengers,
nitromethane, picrate, detergents and dyes. Alcohol oxygenates used
as additives may include methanol, ethanol, isopropanol, and
n-butanol.
[0125] The present invention may produce gasolines of different
types such as straight-run gasoline (which typically contains some
naphthalene and olefins), reformate (which is typically produced in
a catalytic reformer and has a high octane rating with high
aromatic content and low amount of olefins), catalytic cracked
gasoline (also called catalytic cracked naphtha, which is produced
from a catalytic cracker, with a moderate octane rating, high
olefin (alkene) content, and moderate aromatics level), heavy-,
mid-, and high-hydrocrackate (produced from a hydrocracker, with
medium to low octane rating and moderate aromatic levels), alkylate
(produced in an alkylation unit, using as feedstocks isobutane and
alkenes, and contains no aromatics and alkenes and has high MON),
isomerate (obtained by isomerizing low octane straight run gasoline
to iso-paraffins like isooctane, and has medium RON (research
octane number) and MON, but no aromatics and olefins), butane, and
blends thereof.
[0126] In some embodiments, the gasoline can have about 100-95%
saturated hydrocarbons, about 94-90% saturated hydrocarbons, about
89-85% saturated hydrocarbons, about 84-80% saturated hydrocarbons,
about 79-75% saturated hydrocarbons, about 74-70% saturated
hydrocarbons, about 69-65% saturated hydrocarbons, about 64-60%
saturated hydrocarbons, about 59-55% saturated hydrocarbons, about
54-50% saturated hydrocarbons, about 49-45% saturated hydrocarbons,
about 44-40% saturated hydrocarbons, about 39-35% saturated
hydrocarbons, about 34-30% saturated hydrocarbons, about 29-25%
saturated hydrocarbons, about 24-20% saturated hydrocarbons, about
19-15% saturated hydrocarbons, about 14-10% saturated hydrocarbons,
about 9-5% saturated hydrocarbons, and about 4-0% saturated
hydrocarbons.
[0127] In some embodiments, the gasoline can have about 100-95%
aromatic hydrocarbons, about 94-90% aromatic hydrocarbons, about
89-85% aromatic hydrocarbons, about 84-80% aromatic hydrocarbons,
about 79-75% aromatic hydrocarbons, about 74-70% aromatic
hydrocarbons, about 69-65% aromatic hydrocarbons, about 64-60%
aromatic hydrocarbons, about 59-55% aromatic hydrocarbons, about
54-50% aromatic hydrocarbons, about 49-45% aromatic hydrocarbons,
about 44-40% aromatic hydrocarbons, about 39-35% aromatic
hydrocarbons, about 34-30% aromatic hydrocarbons, about 29-25%
aromatic hydrocarbons, about 24-20% aromatic hydrocarbons, about
19-15% aromatic hydrocarbons, about 14-10% aromatic hydrocarbons,
about 9-5% aromatic hydrocarbons, and about 4-0% aromatic
hydrocarbons.
[0128] In some embodiments, the gasoline can have about 100-95%
olefin hydrocarbons, about 94-90% olefin hydrocarbons, about 89-85%
olefin hydrocarbons, about 84-80% olefin hydrocarbons, about 79-75%
olefin hydrocarbons, about 74-70% olefin hydrocarbons, about 69-65%
olefin hydrocarbons, about 64-60% olefin hydrocarbons, about 59-55%
olefin hydrocarbons, about 54-50% olefin hydrocarbons, about 49-45%
olefin hydrocarbons, about 44-40% olefin hydrocarbons, about 39-35%
olefin hydrocarbons, about 34-30% olefin hydrocarbons, about 29-25%
olefin hydrocarbons, about 24-20% olefin hydrocarbons, about 19-15%
olefin hydrocarbons, about 14-10% olefin hydrocarbons, about 9-5%
olefin hydrocarbons, and about 4-0% olefin hydrocarbons.
[0129] In some embodiments, the gasoline contains about 100% pure
isooctane, about 95% pure isooctane, about 90% pure isooctane,
about 85% pure isooctane, about 80% pure isooctane, about 75% pure
isooctane, about 70% pure isooctane, about 65% pure isooctane,
about 60% pure isooctane, about 55% pure isooctane, about 50% pure
isooctane, about 40% pure isooctane, about 35%, about 30% pure
isooctane, about 25% pure isooctane, about 20% pure isooctane,
about 15% pure isooctane, about 10% pure isooctane, and about 5%
pure isooctane.
[0130] In some embodiments, the gasoline contains about 95% pure
n-heptane, about 90% pure n-heptane, about 85% pure n-heptane,
about 80% pure n-heptane, about 75% pure n-heptane, about 70% pure
n-heptane, about 65% pure n-heptane, about 60% pure n-heptane,
about 55% pure n-heptane, about 50% pure n-heptane, about 40% pure
n-heptane, about 35%, about 30% pure n-heptane, about 25% pure
n-heptane, about 20% pure n-heptane, about 15% pure n-heptane,
about 10% pure n-heptane, and about 5% pure n-heptane.
[0131] In one embodiment, the gasoline is made of about 15%
C.sub.4-C.sub.8 straight-chain alkanes, about 25-40%
C.sub.4-C.sub.10 branched alkanes, about 10% cycloalkanes, less
than 25% aromatics (benzene less than 1.0%), and about 10% olefins.
In some embodiments, gasoline can have a smoke point between 12 and
16 mm, and density of 0.71-0.77 kg/L.
[0132] The gasoline produced by the invention described herein can
have a wide range of AKI. AKI is the average of research octane
number (RON), and motor octane number (MON). For example, the
gasoline can have an AKI of about 85, about 86, about 87, about 88,
about 89, about 90, about 91, about 92, about 93, about 94, about
95, about 96, about 97, about 98, about 99, about 100, about 101,
about 102, about 103, about 104 and about 105.
LPG
[0133] One of the fuels produced by the processes described herein
is liquefied petroleum gas or liquid petroleum gas (LPG or LP gas).
LPG can consist of propane, butane, or other flammable mixtures of
hydrocarbons, one or more of which is derived from biomass. In
addition, LPG may contain olefins such as propylene, and butylene
in small concentrations, one or more of which is derived from
biomass. Other additives can include odorants such as ethanediol,
tetrahydrothiophene (thiophane) or amyl mercaptan. The LPG can be
used as fuel in various systems, including heating appliances,
cooking equipment, and vehicles. It can also be used as an aerosol
propellant and a refrigerant. When specifically used as a vehicle
fuel it is often referred to as autogas.
Heating Oil
[0134] Heating oil can also be produced by the processes described
herein. Heating oil can consist of hydrocarbons in the C14-C22
range, one or more of which is derived from biomass. Heating oil
produced herein can be used to fuel furnaces or boilers in
buildings. The heating oil produced by the invention can have
several advantages, such as being clean, non-explosive, highly
efficient and producing negligible amounts of smoke and soot
emissions. Heating oils of different grades can be produced,
including those graded 1 through 6. This could also include diesel,
such as grade 2 diesel.
RP-1 (Rocket Fuel)
[0135] RP-1 also called Rocket Propellent-1 or Refined Petroleum-1,
is used as a rocket fuel and can be produced by the methods
described herein. RP-1 can be produced by selecting desirable
hydrocarbons derived from biomass that increase resistance to
thermal breakdown. For example, highly branched and cyclic alkanes
are favored over linear alkanes. Alkenes and aromatic compounds are
held at very low levels. In one embodiment, RP-1 can have a
freezing point of -73.degree. C., density of 0.81-1.02 g/ml and a
flash point of 43.degree. C.
BTX
[0136] BTX can also be produced by this invention. BTX can contain
mixtures of benzene, toluene, and the three xylene isomers, one or
more of which is derived from biomass. In some embodiments,
ethylbenzene is included, and the mixture is then referred to as
BTEX. BTX can be produced by the recovery of aromatic compounds
from the processes described herein.
Processing to Prepare Fuels
[0137] FIG. 1 shows processes for manufacturing a biofuel, such as
any described above. Biofuels can be prepared from sugars and
fermentation products from a feedstock (e.g., cellulosic or
lignocellulosic materials). In an initial step (101), the method
includes, optionally, mechanically treating a cellulosic and/or
lignocellulosic feedstock. Before and/or after this treatment, the
feedstock can be treated with another physical treatment (103), for
example irradiation, sonication, steam explosion, oxidation,
pyrolysis or combinations of these, to reduce or further reduce its
recalcitrance. A sugar solution e.g., including glucose, xylose and
combinations of these, is formed by saccharifying the feedstock
(104). The saccharification can be, for example, accomplished
efficiently by the addition of one or more enzymes, e.g.,
cellulases and xylanases (102) and/or one or more acids in any
order. The sugar (or saccharide units) can be further processed in
step 108 into one or more components of a biofuel. For example, a
saccharide can be transformed by catalytic hydrogenation into
polyhydric alcohols, or into short chain oxygenates by
hydrogenolysis to provide one or more components used in a
biofuel.
[0138] Alternatively, the sugar solution can be bioprocessed (105),
for example by utilizing an organism to ferment the sugars to a
primary product, e.g., an alcohol, a carboxylic acid, a ketone,
hydrogen and combinations of these to produce an intermediate
building block. Optionally, the fermentation can include more than
one organism and comprises more than one fermentation step, for
example producing one or more products simultaneously or
sequentially. Optionally, the fermentation can be selective to one
sugar. Optionally, the bioprocessing can include isolation (106) of
the intermediate building block, for example by a column
extraction, solvent extraction and/or by distillation.
[0139] The intermediate building block of the bioprocessing step
can be catalytically processed (107) to provide one or more of the
components used in a biofuel. For example, an alcohol can be
converted to alkenes by dehydration, and then oligomerized into
higher olefins. The higher olefins can be subsequently oligomerized
and/or hydrogenated to make higher molecular weight alkanes. In
another example, a carboxylic acid can be hydrogenated to an
alcohol, esterified and/or esterified and then hydrogenated to
provide a hydrocarbon component of a biofuel. Catalytic or chemical
processing can occur in a batch reactor, or, in a continuous
reactor. Optionally, the processing can include isolation of the
product for example by a column extraction, solvent extraction
and/or by distillation.
[0140] In other aspects, the process can be designed to only
partially convert the starting alcohol into a fuel. For example,
the intermediate building block can be ethanol and the catalyst
conversion system can be designed to convert only a portion of the
ethanol, for example, by controlling flow rate of alcohol, e.g.,
ethanol, or reaction temperature over the catalyst bed. In another
aspect the process can be designed to convert processed biomass and
biomass-derived products into fuel through a catalyst-facilitated
process. The resulting product can be a mixture of a hydrocarbon
fuel and alcohol, so that no additional blending in needed. In
certain embodiments, the final ethanol content can be 10-15% as is
required by many regulatory agencies. Ethanol fuel mixtures have
"E" numbers which describe the percentage of ethanol fuel in the
mixture by volume, for example, E85 is 85% anhydrous ethanol and
15% gasoline. For example, E10, a fuel mixture of 10% anhydrous
ethanol and 90% gasoline sometimes called gasohol, can be used in
the internal combustion engines of most automobiles. Blends from
E20 to E25 have been used in Brazil since the late 1970s. E85 is
commonly used in the U.S. and Europe for flexible-fuel
vehicles.
Types of Biomass
[0141] Generally, any biomass material that is or includes
carbohydrates composed entirely of one or more saccharide units or
that include one or more saccharide units can be processed by any
of the methods described herein. The biomass can be recalcitrant
biomass or recalcitrant-reduced biomass. For example, the biomass
material can be cellulosic or lignocellulosic materials, or starchy
materials, such as kernels of corn, grains of rice or other foods,
or materials that are or that include one or more low molecular
weight sugars, such as sucrose or cellobiose.
[0142] For example, such materials can include paper, paper
products, wood, wood-related materials, particle board, grasses,
rice hulls, bagasse, cotton, jute, hemp, flax, bamboo, sisal,
abaca, straw, corn cobs, rice hulls, coconut hair, algae, seaweed,
cotton, synthetic celluloses, or mixtures of any of these. Suitable
materials include those listed in the Summary section, above.
[0143] Fiber sources include cellulosic fiber sources, including
paper and paper products (e.g., polycoated paper and Kraft paper),
and lignocellulosic fiber sources, including wood, and wood-related
materials, e.g., particle board. Other suitable fiber sources
include natural fiber sources, e.g., grasses, rice hulls, bagasse,
cotton, jute, hemp, flax, bamboo, sisal, abaca, straw, corn cobs,
rice hulls, coconut hair; fiber sources high in .alpha.-cellulose
content, e.g., cotton; and synthetic fiber sources, e.g., extruded
yarn (oriented yarn or un-oriented yarn). Natural or synthetic
fiber sources can be obtained from virgin scrap textile materials,
e.g., remnants or they can be post-consumer waste, e.g., rags. When
paper products are used as fiber sources, they can be virgin
materials, e.g., scrap virgin materials, or they can be
post-consumer waste. Aside from virgin materials, post-consumer,
industrial (e.g., offal), and processing waste (e.g., effluent from
paper processing) can also be used as fiber sources. Also, the
fiber source can be obtained or derived from human (e.g., sewage),
animal or plant wastes. Additional fiber sources have been
described in U.S. Pat. Nos. 6,448,307, 6,258,876, 6,207,729,
5,973,035 and 5,952,105.
[0144] Examples of biomass include renewable, organic matter, such
as plant biomass (defined below), microbial biomass (defined
below), animal biomass (e.g., any animal by-product, animal waste,
etc.) and municipal waste biomass including any and all
combinations of these biomass materials.
[0145] Plant biomass and lignocellulosic biomass include organic
matter (woody or non-woody) derived from plants, especially matter
available on a sustainable basis. Examples include biomass from
agricultural or food crops (e.g., sugarcane, sugar beets or corn
kernels) or an extract therefrom (e.g., sugar from sugarcane and
corn starch from corn), agricultural crop wastes and residues such
as corn stover, wheat straw, rice straw, sugar cane bagasse, and
the like. Plant biomass further includes, but is not limited to,
trees, woody energy crops, wood wastes and residues such as
softwood forest thinnings, barky wastes, sawdust, paper and pulp
industry waste streams, wood fiber, and the like. Additionally,
grass crops, such as switchgrass and the like have potential to be
produced on a large-scale as another plant biomass source. For
urban areas, the plant biomass feedstock includes yard waste (e.g.,
grass clippings, leaves, tree clippings, and brush) and vegetable
processing waste.
[0146] Lignocellulosic feedstock can be plant biomass such as, but
not limited to, non-woody plant biomass, cultivated crops, such as,
but not limited to, grasses, for example, but not limited to, C4
grasses, such as switchgrass, cord grass, rye grass, miscanthus,
reed canary grass, or a combination thereof, or sugar processing
residues such as bagasse, or beet pulp, agricultural residues, for
example, soybean stover, corn stover, rice straw, rice hulls,
barley straw, corn cobs, wheat straw, canola straw, rice straw, oat
straw, oat hulls, corn fiber, recycled wood pulp fiber, sawdust,
hardwood, for example aspen wood and sawdust, softwood, or a
combination thereof. Further, the lignocellulosic feedstock may
include cellulosic waste material such as, but not limited to,
newsprint, cardboard, sawdust, and the like. Lignocellulosic
feedstock may include one species of fiber or alternatively,
lignocellulosic feedstock may include a mixture of fibers that
originate from different lignocellulosic feedstocks. Furthermore,
the lignocellulosic feedstock may comprise fresh lignocellulosic
feedstock, partially dried lignocellulosic feedstock, fully dried
lignocellulosic feedstock or a combination thereof.
[0147] Microbial biomass includes biomass derived from naturally
occurring or genetically modified unicellular organisms and/or
multicellular organisms, e.g., organisms from the ocean, lakes,
bodies of water, e.g., salt water or fresh water, or on land, and
that contains a source of carbohydrate (e.g., cellulose). Microbial
biomass can include, but is not limited to, for example protists
(e.g., animal (e.g., protozoa such as flagellates, amoeboid,
ciliates, and sporozoa) and plant (e.g., algae such alveolates,
chlorarachniophytes, cryptomonads, euglenids, glaucophytes,
haptophytes, red algae, stramenopiles, and viridaeplantae)),
seaweed, plankton (e.g., macroplankton, mesoplankton,
microplankton, nanoplankton, picoplankton, and femptoplankton),
phytoplankton, bacteria (e.g., gram positive bacteria, gram
negative bacteria, and extremophiles), yeast and/or mixtures of
these. In some instances, microbial biomass can be obtained from
natural sources, e.g., the ocean, lakes, bodies of water, e.g.,
salt water or fresh water, or on land. Alternatively, or in
addition, microbial biomass can be obtained from culture systems,
e.g., large scale dry and wet culture systems.
[0148] Animal biomass includes any organic waste material such as
animal-derived waste material or excrement or human waste material
or excrement (e.g., manure and sewage).
[0149] Starchy materials include starch itself, e.g., corn starch,
wheat starch, potato starch or rice starch, a derivative of starch,
or a material that includes starch, such as an edible food product
or a crop. For example, the starchy material can be arracacha,
buckwheat, banana, barley, cassava, kudzu, oca, sago, sorghum,
regular household potatoes, sweet potato, taro, yams, or one or
more beans, such as favas, lentils or peas. Blends of any two or
more starchy materials are also starchy materials. In particular
embodiments, the starchy material is derived from corn. Various
corn starches and derivatives are described in "Corn Starch," Corn
Refiners Association (11th Edition, 2006), the contents of which
are incorporated herein by reference.
[0150] Biomass materials that include low molecular weight sugars
can, e.g., include at least about 0.5 percent by weight of the low
molecular sugar, e.g., at least about 2, 3, 4, 5, 6, 7, 8, 9, 10,
12.5, 25, 35, 50, 60, 70, 80, 90 or even at least about 95 percent
by weight of the low molecular weight sugar. In some instances, the
biomass is composed substantially of the low molecular weight
sugar, e.g., greater than 95 percent by weight, such as 96, 97, 98,
99 or substantially 100 percent by weight of the low molecular
weight sugar.
[0151] Biomass materials that include low molecular weight sugars
can be agricultural products or food products, such as sugarcane
and sugar beets or an extract therefrom, e.g., juice from
sugarcane, or juice from sugar beets. Biomass materials that
include low molecular weight sugars can be substantially pure
extracts, such as raw or crystallized table sugar (sucrose). Low
molecular weight sugars include sugar derivatives. For example, the
low molecular weight sugars can be oligomeric (e.g., equal to or
greater than a 4-mer, 5-mer, 6-mer, 7-mer, 8-mer, 9-mer or 10-mer),
trimeric, dimeric, or monomeric. When the carbohydrates are formed
of more than a single repeat unit, each repeat unit can be the same
or different. Specific examples of low molecular weight sugars
include cellobiose, lactose, sucrose, glucose and xylose, along
with derivatives thereof. In some instances, sugar derivatives are
more rapidly dissolved in solution or utilized by microbes to
provide a useful material, such as ethanol or butanol.
[0152] In some embodiments, feedstocks are obtained from plants
that have been modified with respect to a wild type variety, e.g.,
by genetic modification or other types of modification, can be
processed to produce useful intermediates and products such as
those described herein. Such modifications may be for example, by
any of the methods described in any patent or patent application
referenced herein. As another example, plants may be modified
through the iterative steps of selection and breeding to obtain
desired traits in a plant. Furthermore, the plants can have had
genetic material removed, modified, silenced and/or added with
respect to the wild type variety. For example, genetically modified
plants can be produced by recombinant DNA methods, where genetic
modifications include introducing or modifying specific genes from
parental varieties, or, for example, by using transgenic breeding
wherein a specific gene or genes are introduced to a plant from a
different species of plant and/or bacteria. Another way to create
genetic variation is through mutation breeding wherein new alleles
are artificially created from endogeneous genes or by exogenous
genes.
[0153] The advantages of plant modification include, for example,
an enhancement of resistance to insects, fungal diseases, and other
pests and disease-causing agents; an increased tolerance to
herbicides; increased drought resistance; an extended temperature
range; enhanced tolerance to poor soil; enhanced stability or
shelf-life; a greater yield; larger fruit size; stronger stalks;
enhanced shatter resistance; reduced time to crop maturity; more
uniform germination times; higher or modified starch production;
enhanced nutrient production, such as enhanced steroid, sterol,
hormone, fatty acid, glycerol, polyhydroxyalkanoate, amino acid,
vitamin and/or protein production; modified lignin content;
enhanced cellulose, hemicellulose and/or lignin degradation;
inclusion of a phenotype marker to allow qualitative detection
(e.g., seed coat color); and modified phytate content. Any
feedstock materials derived from these modified plants can also
benefit from these many advantages. For example, a feedstock
material such as a lignocellulosic material can have better shelf
life, be easier to process, have a better land-to-energy conversion
ratio, and/or have a better nutritional value to any microbes that
are used in processing of the lignocellulosic material. In
addition, any feedstock material derived from such plants can be
less expensive and/or more plentiful. In some cases, modified
plants can be grown in a greater variety of climates and/or soil
types, for example in marginal or depleted soils.
[0154] In some embodiments, feedstock materials can be obtained
from modified plants having an increased resistance to disease. For
example, potatoes which have reduced symptoms from the infestation
of fungal pathogen Phytophthora infestans are discussed in U.S.
Pat. No. 7,122,719. A possible advantage of such resistance is that
the yield, quality and shelf life of the feedstock materials may be
improved.
[0155] In some embodiments, feedstock materials can be obtained
from modified plants with increased resistance to parasites, for
example, by encoding genes for the production of 8-endotoxins as
exemplified in U.S. Pat. No. 6,023,013. A possible advantage of
such resistance is that the yield, quality and shelf life of the
feedstock materials may be improved.
[0156] Feedstock materials can also be obtained from modified
plants having an increased resistance to herbicides. For example,
the alfalfa plant J-101, as described in U.S. Pat. No. 7,566,817,
has an increased resistance to glyphosphate herbicides. As a
further example, modified plants described in U.S. Pat. No.
6,107,549 have an increased resistance to pyridine family
herbicides. Furthermore, modified plants described in U.S. Pat. No.
7,498,429 have increased resistance to imidazolinones. A possible
advantage of such resistance is that the yield and quality of the
feedstock materials may be improved.
[0157] In some embodiments, feedstock materials can be obtained
from modified plants having an increased stress resistance (for
example, water deficit, cold, heat, salt, pest, disease, or
nutrient stress). For example, such plants have been described in
U.S. Pat. No. 7,674,952. A possible advantage of such resistance is
that the yield and quality of the feedstock materials may be
improved. Moreover, such plants may be grown in adverse conditions,
e.g., marginal or depleted soil or in a harsh climate.
[0158] In some embodiments, feedstock materials can be obtained
from modified plants with improved characteristics such as larger
fruits. Such plants have been described in U.S. Pat. No. 7,335,812.
A possible advantage of such resistance is that the yield and
quality of the feedstock materials may be improved.
[0159] In some embodiments, feedstock materials can be obtained
from modified plants with improved characteristics such reduced pod
shatter. Such plants have been described in U.S. Pat. No.
7,659,448. A possible advantage of such resistance is that the
yield and quality of the feedstock materials may be improved.
[0160] In some embodiments, feedstock materials can be obtained
from modified plants having enhanced o modified starch content.
Such plants have been described in U.S. Pat. No. 6,538,178. A
possible advantage of such modification is that the quality of the
feedstock is improved.
[0161] In some embodiments, feedstock materials can be obtained
from modified plants with a modified oil, fatty acid or glycol
production. Such plants have been described in U.S. Pat. No.
7,405,344. Fatty acids and oils are excellent substrates for
microbial energy-yielding metabolism and may provide an advantage
to downstream processing of the feedstock for, for example, fuel
production. Fatty acids and oil variation may also be advantageous
in changing the viscosity and solubility of various components
during downstream processing of the feedstock. The spent feedstock
may have a better nutrient mix for use as animal feed or have
higher calorie content useful as a direct fuel for burning.
[0162] In some embodiments, feedstock materials can be obtained
from modified plants with a modified steroid, sterol and hormone
content. Such plants have been described in U.S. Pat. No.
6,822,142. A possible advantage is that this may provide a better
nutrient mix for microorganisms used in processing of the
feedstock. After processing, the spent feedstock may have a better
nutrient mix for use as animal feed.
[0163] In some embodiments, feedstock materials can be obtained
from modified plants with polyhydroxyalkanoate producing ability.
Such plants have been described in U.S. Pat. No. 6,175,061.
Polyhydroxyalkanoates are a useful energy and carbon reserve for
various microorganisms and may be beneficial to the microorganisms
used in downstream feedstock processing. Also, since
polyhydroxyalkanoate is biodegradable, it may impart advantages by
possibly reducing recalcitrance in plant material after an aging
period of the stored feedstock. Further downstream, the spent
feedstock may have a better nutrient mix for use as animal feed or
have higher calorie content useful as a direct fuel for
burning.
[0164] In some embodiments, feedstock materials can be obtained
from modified plants with enhanced amino acid production. Such
plants have been described in U.S. Pat. No. 7,615,621. A possible
advantage is that this may provide a better nutrient mix for
microorganisms used in processing of the feedstock. After
processing, the spent feedstock may have a better nutrient mix for
use as animal feed.
[0165] In some embodiments, feedstock materials can be obtained
from modified plants with elevated synthesis of vitamins. Such
plants have been described in U.S. Pat. No. 6,841,717. A possible
advantage is that this may provide a better nutrient mix for
microorganisms used in processing of the feedstock. After
processing, the spent feedstock may have a better nutrient mix for
use as animal feed.
[0166] In some embodiments, feedstock materials can be obtained
from modified plants that degrade lignin and cellulose in the plant
after harvest. Such plants have been described in U.S. Pat. No.
7,049,485. Feedstock materials can also be obtained from modified
plants with modified lignin content. Such plants have been
described in U.S. Pat. No. 7,799,906. A possible advantage of such
plants is reduced recalcitrance relative to the wild types of the
same plants.
[0167] In some embodiments, feedstock materials can be obtained
from modified plants with a modified phenotype for easy qualitative
detection. Such plants have been described in U.S. Pat. No.
7,402,731. A possible advantage is ease of managing crops and seeds
for different product streams such as biofuels, building materials
and animal feed.
[0168] In some embodiments, feedstock materials can be obtained
from modified plants with a reduced amount of phytate. Such plants
have been described in U.S. Pat. No. 7,714,187. A possible
advantage is that this may provide a better nutrient mix for
microorganisms used in processing of the feedstock. After
processing, the spent feedstock may have a better nutrient mix for
use as animal feed.
[0169] In some embodiments, the feedstock can be a combination of
any of the above-described types of feedstock materials, and any
other material. In some embodiments, the above-described biomass
can be combined with each other or other biomass non-biological
ingredients to provide feedstock material for the processes
described herein.
Physical Treatment of Biomass
[0170] If the feedstock is to be treated with a physical treatment,
the manufacturing facility will be retrofitted to include a
physical treatment system. Alternatively, the manufacturing
facility may not include this system, and the materials may be
physically treated, if necessary, at a remote location. Physical
treatment processes can include one or more of any of those
described herein, such as mechanical treatment, chemical treatment,
irradiation, sonication, oxidation, pyrolysis or steam explosion.
Treatment methods can be used in combinations of two, three, four,
or even all of these technologies (in any order). When more than
one treatment methods are used, the methods can be applied at the
same time or at different times. Other processes that change a
molecular structure of a biomass feedstock may also be used, alone
or in combination with the processes disclosed herein. One or more
of the treatment processes described below may be included in the
recalcitrance reducing system discussed above. Alternatively, or in
addition, other processes for reducing recalcitrance may be
included.
Mechanical Treatments
[0171] In some cases, methods can include mechanically treating the
biomass feedstock. Mechanical treatments include, for example,
cutting, milling, pressing, grinding, shearing and chopping.
Milling may include, for example, ball milling, hammer milling,
rotor/stator dry or wet milling, or other types of milling. Other
mechanical treatments include, e.g., stone grinding, cracking,
mechanical ripping or tearing, pin grinding or air attrition
milling. Mechanical treatment can be advantageous for "opening up,"
"stressing," breaking and shattering the cellulosic or
lignocellulosic materials, making the cellulose of the materials
more susceptible to chain scission and/or reduction of
crystallinity. The open materials can also be more susceptible to
oxidation when irradiated.
[0172] In some cases, the mechanical treatment may include an
initial preparation of the feedstock as received, e.g., size
reduction of materials, such as by cutting, grinding, shearing,
pulverizing or chopping. For example, in some cases, loose
feedstock (e.g., recycled paper, starchy materials, or switchgrass)
is prepared by shearing or shredding.
[0173] Alternatively, or in addition, the feedstock material can be
physically treated by one or more of the other physical treatment
methods, e.g., chemical treatment, radiation, sonication,
oxidation, pyrolysis or steam explosion, and then mechanically
treated. This sequence can be advantageous since materials treated
by one or more of the other treatments, e.g., irradiation or
pyrolysis, tend to be more brittle and, therefore, it may be easier
to further change the molecular structure of the material by
mechanical treatment.
[0174] In some embodiments, the feedstock material is in the form
of a fibrous material, and mechanical treatment includes shearing
to expose fibers of the fibrous material. Shearing can be
performed, for example, using a rotary knife cutter. Other methods
of mechanically treating the feedstock include, for example,
milling or grinding. Milling may be performed using, for example, a
hammer mill, ball mill, colloid mill, conical or cone mill, disk
mill, edge mill, Wiley mill or grist mill. Grinding may be
performed using, for example, a stone grinder, pin grinder, coffee
grinder, or burr grinder. Grinding may be provided, for example, by
a reciprocating pin or other element, as is the case in a pin mill.
Other mechanical treatment methods include mechanical ripping or
tearing, other methods that apply pressure to the fibers, and air
attrition milling. Suitable mechanical treatments further include
any other technique that changes the molecular structure of the
feedstock.
[0175] If desired, the mechanically treated material can be passed
through a screen, e.g., having an average opening size of 1.59 mm
or less ( 1/16 inch, 0.0625 inch). In some embodiments, shearing,
or other mechanical treatment, and screening are performed
concurrently. For example, a rotary knife cutter can be used to
concurrently to shear and screen the feedstock. The feedstock is
sheared between stationary blades and rotating blades to provide a
sheared material that passes through a screen, and is captured in a
bin. The bin can have a pressure below nominal atmospheric
pressure, e.g., at least 10 percent below nominal atmospheric
pressure, e.g., at least 25 percent below nominal atmospheric
pressure, at least 50 percent below nominal atmospheric pressure,
or at least 75 percent below nominal atmospheric pressure. In some
embodiments, a vacuum source is utilized to maintain the bin below
nominal atmospheric pressure.
[0176] The cellulosic or lignocellulosic material can be
mechanically treated in a dry state (e.g., having little or no free
water on its surface), a hydrated state (e.g., having up to ten
percent by weight absorbed water), or in a wet state, e.g., having
between about 10 percent and about 75 percent by weight water. The
fiber source can even be mechanically treated while partially or
fully submerged under a liquid, such as water, ethanol or
isopropanol. The cellulosic or lignocellulosic material can also be
mechanically treated under a gas (such as a stream or atmosphere of
gas other than air), e.g., oxygen or nitrogen, or steam.
[0177] If desired, lignin can be removed from any feedstock
materials that includes lignin. Also, to aid in the breakdown of
the materials that include cellulose, the material can be treated
prior to or during mechanical treatment or irradiation with heat, a
chemical (e.g., mineral acid, base or a strong oxidizer such as
sodium hypochlorite) and/or an enzyme. For example, grinding can be
performed in the presence of an acid.
[0178] Mechanical treatment systems can be configured to produce
streams with specific characteristics such as, for example,
specific maximum sizes, specific length-to-width, or specific
surface areas ratios. Mechanical treatment can increase the rate of
reactions or reduce the processing time required by opening up the
materials and making them more accessible to processes and/or
reagents, such as reagents in a solution. The bulk density of
feedstocks can also be controlled using mechanical treatment. For
example, in some embodiments, after mechanical treatment the
material has a bulk density of less than 0.25 g/cm.sup.3, e.g.,
0.20 g/cm.sup.3, 0.15 g/cm.sup.3, 0.10 g/cm.sup.3, 0.05 g/cm.sup.3
or less, e.g., 0.025 g/cm.sup.3. Bulk density is determined using
ASTM D1895B. Briefly, the method involves filling a measuring
cylinder of known volume with a sample and obtaining a weight of
the sample. The bulk density is calculated by dividing the weight
of the sample in grams by the known volume of the cylinder in cubic
centimeters.
[0179] If the feedstock is a fibrous material, the fibers of the
mechanically treated material can have a relatively large average
length-to-diameter ratio (e.g., greater than 20-to-1), even if they
have been sheared more than once. In addition, the fibers of the
fibrous materials described herein may have a relatively narrow
length and/or length-to-diameter ratio distribution. As used
herein, average fiber widths (e.g., diameters) are those determined
optically by randomly selecting approximately 5,000 fibers. Average
fiber lengths are corrected length-weighted lengths. BET (Brunauer,
Emmet and Teller) surface areas are multi-point surface areas, and
porosities are those determined by mercury porosimetry.
[0180] If the feedstock is a fibrous material, the average
length-to-diameter ratio of fibers of the mechanically treated
material can be, e.g., greater than 8/1, e.g., greater than 10/1,
greater than 15/1, greater than 20/1, greater than 25/1, or greater
than 50/1. An average fiber length of the mechanically treated
material can be, e.g., between about 0.5 mm and 2.5 mm, e.g.,
between about 0.75 mm and 1.0 mm, and an average width (e.g.,
diameter) of the fibrous material can be, e.g., between about 5
.mu.m and 50 .mu.m, e.g., between about 10 .mu.m and 30 .mu.m.
[0181] In some embodiments, if the feedstock is a fibrous material,
a standard deviation of the fiber length of the mechanically
treated material is less than 60 percent of an average fiber length
of the mechanically treated material, e.g., less than 50 percent of
the average length, less than 40 percent of the average length,
less than 25 percent of the average length, less than 10 percent of
the average length, less than 5 percent of the average length, or
even less than 1 percent of the average length.
[0182] In some embodiments, a BET surface area of the mechanically
treated material is greater than 0.1 m.sup.2/g, e.g., greater than
0.25 m.sup.2/g, greater than 0.5 m.sup.2/g, greater than 1.0
m.sup.2/g, greater than 1.5 m.sup.2/g, greater than 1.75 m.sup.2/g,
greater than 5.0 m.sup.2/g, greater than 10 m.sup.2/g, greater than
25 m.sup.2/g, greater than 35 m.sup.2/g, greater than 50 m.sup.2/g,
greater than 60 m.sup.2/g, greater than 75 m.sup.2/g, greater than
100 m.sup.2/g, greater than 150 m.sup.2/g, greater than 200
m.sup.2/g, or even greater than 250 m.sup.2/g.
[0183] A porosity of the mechanically treated material can be,
e.g., greater than 20 percent, greater than 25 percent, greater
than 35 percent, greater than 50 percent, greater than 60 percent,
greater than 70 percent, greater than 80 percent, greater than 85
percent, greater than 90 percent, greater than 92 percent, greater
than 94 percent, greater than 95 percent, greater than 97.5
percent, greater than 99 percent, or even greater than 99.5
percent.
[0184] In some situations, it can be desirable to prepare a low
bulk density material, densify the material (e.g., to make it
easier and less costly to transport to another site), and then
revert the material to a lower bulk density state. Densified
materials can be processed by any of the methods described herein,
or any material processed by any of the methods described herein
can be subsequently densified, e.g., as disclosed in WO
2008/073186.
Radiation Treatment
[0185] One or more radiation processing sequences can be used to
process the feedstock, and to provide a structurally modified
material which functions as input to further processing steps
and/or sequences. Irradiation can, for example, reduce the
molecular weight and/or crystallinity of feedstock. In some
embodiments, energy deposited in a material that releases an
electron from its atomic orbital is used to irradiate the
materials. The radiation may be provided by 1) heavy charged
particles, such as alpha particles or protons, 2) electrons,
produced, for example, in beta decay or electron beam accelerators,
or 3) electromagnetic radiation, for example, gamma rays, x rays,
or ultraviolet rays. In one approach, radiation produced by
radioactive substances can be used to irradiate the feedstock. In
some embodiments, any combination in any order or concurrently of
(1) through (3) may be utilized. In another approach,
electromagnetic radiation (e.g., produced using electron beam
emitters) can be used to irradiate the feedstock. The doses applied
depend on the desired effect and the particular feedstock. For
example, high doses of radiation can break chemical bonds within
feedstock components. In some instances when chain scission is
desirable and/or polymer chain functionalization is desirable,
particles heavier than electrons, such as protons, helium nuclei,
argon ions, silicon ions, neon ions, carbon ions, phosphorus ions,
oxygen ions or nitrogen ions can be utilized. When ring-opening
chain scission is desired, positively charged particles can be
utilized for their Lewis acid properties for enhanced ring-opening
chain scission. For example, when maximum oxidation is desired,
oxygen ions can be utilized, and when maximum nitration is desired,
nitrogen ions can be utilized.
[0186] In one method, a first material that is or includes
cellulose having a first number average molecular weight (M.sub.N1)
is irradiated, e.g., by treatment with ionizing radiation (e.g., in
the form of gamma radiation, X-ray radiation, 100 nm to 280 nm
ultraviolet (UV) light, a beam of electrons or other charged
particles) to provide a second material that includes cellulose
having a second number average molecular weight (M.sub.N2) lower
than the first number average molecular weight. The second material
(or the first and second material) can be combined with a
microorganism (with or without enzyme treatment) that can utilize
the second and/or first material or its constituent sugars or
lignin to produce a useful intermediate that is or includes
hydrogen, an alcohol (e.g., ethanol or butanol, such as n-, sec- or
t-butanol), an organic acid, a hydrocarbon or mixtures of any of
these.
[0187] Since the second material has cellulose having a reduced
molecular weight relative to the first material, and in some
instances, a reduced crystallinity as well, the second material is
generally more dispersible, swellable and/or soluble in a solution
containing a microorganism and/or an enzyme. These properties make
the second material more susceptible to chemical, enzymatic and/or
biological attack relative to the first material, which can greatly
improve the production rate and/or production level of a desired
product, e.g., ethanol. Radiation can also sterilize the materials
or any media needed to bioprocess the material. In some
embodiments, the second number average molecular weight (M.sub.N2)
is lower than the first number average molecular weight (MN1) by
more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, 50
percent, 60 percent, or even more than about 75 percent.
[0188] In some instances, the second material has cellulose that
has as crystallinity (C.sub.2) that is lower than the crystallinity
(C.sub.1) of the cellulose of the first material. For example,
(C.sub.2) can be lower than (C.sub.1) by more than about 10
percent, e.g., 15, 20, 25, 30, 35, 40, or even more than about 50
percent.
[0189] In some embodiments, the starting crystallinity index (prior
to irradiation) is from about 40 to about 87.5 percent, e.g., from
about 50 to about 75 percent or from about 60 to about 70 percent,
and the crystallinity index after irradiation is from about 10 to
about 50 percent, e.g., from about 15 to about 45 percent or from
about 20 to about 40 percent. However, in some embodiments, e.g.,
after extensive irradiation, it is possible to have a crystallinity
index of lower than 5 percent. In some embodiments, the material
after irradiation is substantially amorphous.
[0190] In some embodiments, the starting number average molecular
weight (prior to irradiation) is from about 200,000 to about
3,200,000, e.g., from about 250,000 to about 1,000,000 or from
about 250,000 to about 700,000, and the number average molecular
weight after irradiation is from about 50,000 to about 200,000,
e.g., from about 60,000 to about 150,000 or from about 70,000 to
about 125,000. However, in some embodiments, e.g., after extensive
irradiation, it is possible to have a number average molecular
weight of less than about 10,000 or even less than about 5,000.
[0191] In some embodiments, the second material can have a level of
oxidation (O.sub.2) that is higher than the level of oxidation
(O.sub.1) of the first material. A higher level of oxidation of the
material can aid in its dispersability, swellability and/or
solubility, further enhancing the material's susceptibility to
chemical, enzymatic or biological attack. In some embodiments, to
increase the level of the oxidation of the second material relative
to the first material, the irradiation is performed under an
oxidizing environment, e.g., under a blanket of air or oxygen,
producing a second material that is more oxidized than the first
material. For example, the second material can have more hydroxyl
groups, aldehyde groups, ketone groups, ester groups or carboxylic
acid groups, which can increase its hydrophilicity.
Ionizing Radiation
[0192] The cellulosic or lignocellulosic material can be treated to
ionizing radiation in a dry state (e.g., having little or no free
water on its surface), a hydrated state (e.g., having up to ten
percent by weight absorbed water), or in a wet state, e.g., having
between about 10 percent and about 75 percent by weight water. Each
form of radiation ionizes the carbon-containing material via
particular interactions, as determined by the energy of the
radiation. Heavy charged particles primarily ionize matter via
Coulomb scattering; furthermore, these interactions produce
energetic electrons that may further ionize matter. Alpha particles
are identical to the nucleus of a helium atom and are produced by
the alpha decay of various radioactive nuclei, such as isotopes of
bismuth, polonium, astatine, radon, francium, radium, several
actinides, such as actinium, thorium, uranium, neptunium, curium,
californium, americium, and plutonium.
[0193] When particles are utilized, they can be neutral
(uncharged), positively charged or negatively charged. When
charged, the charged particles can bear a single positive or
negative charge, or multiple charges, e.g., one, two, three or even
four or more charges. In instances in which chain scission is
desired, positively charged particles may be desirable, in part due
to their acidic nature. When particles are utilized, the particles
can have the mass of a resting electron, or greater, e.g., 500,
1000, 1500, 2000, 10,000 or even 100,000 times the mass of a
resting electron. For example, the particles can have a mass of
from about 1 atomic unit to about 150 atomic units, e.g., from
about 1 atomic unit to about 50 atomic units, or from about 1 to
about 25, e.g., 1, 2, 3, 4, 5, 10, 12 or 15 amu.
[0194] Accelerators used to accelerate the particles can be
electrostatic DC, electrodynamic DC, RF linear, magnetic induction
linear or continuous wave. For example, cyclotron type accelerators
are available from IBA, Belgium, such as the RHODATRON.RTM. system
(an electron accelerator based upon the principle of re-circulating
a beam through successive diameters of a single coaxial cavity
resonating in metric waves), while DC type accelerators are
available from RDI, now IBA Industrial, such as the DYNAMITRON.RTM.
(an electron beam particle accelerator developed by IBA
Industrial). Ions and ion accelerators are discussed in
Introductory Nuclear Physics, Kenneth S. Krane, John Wiley &
Sons, Inc. (1988), Krsto Prelec, FIZIKA B 6 (1997) 4, 177-206, Chu,
William T., "Overview of Light-Ion Beam Therapy" Columbus-Ohio,
ICRU-IAEA Meeting, 18-20 Mar. 2006, Iwata, Y. et al.,
"Alternating-Phase-Focused IH-DTL for Heavy-Ion Medical
Accelerators" Proceedings of EPAC 2006, Edinburgh, Scotland and
Leaner, C. M. et al., "Status of the Superconducting ECR Ion Source
Venus" Proceedings of EPAC 2000, Vienna, Austria.
[0195] Gamma radiation has the advantage of a significant
penetration depth into a variety of materials. Sources of gamma
rays include radioactive nuclei, such as isotopes of cobalt,
calcium, technicium, chromium, gallium, indium, iodine, iron,
krypton, samarium, selenium, sodium, thalium, and xenon.
[0196] Sources of x rays include electron beam collision with metal
targets, such as tungsten or molybdenum or alloys, or compact light
sources, such as those produced commercially by Lyncean.
[0197] Sources for ultraviolet radiation include deuterium or
cadmium lamps.
[0198] Sources for infrared radiation include sapphire, zinc, or
selenide window ceramic lamps.
[0199] Sources for microwaves include klystrons, Slevin type RF
sources, or atom beam sources that employ hydrogen, oxygen, or
nitrogen gases.
[0200] In some embodiments, a beam of electrons is used as the
radiation source. A beam of electrons has the advantages of high
dose rates (e.g., 1, 5, or even 10 Mrad per second), high
throughput, less containment, and less confinement equipment.
Electrons can also be more efficient at causing chain scission. In
addition, electrons having energies of 4-10 MeV can have a
penetration depth of 5 to 30 mm or more, such as 40 mm.
[0201] Electron beams can be generated, e.g., by electrostatic
generators, cascade generators, transformer generators, low energy
accelerators with a scanning system, low energy accelerators with a
linear cathode, linear accelerators, and pulsed accelerators.
Electrons as an ionizing radiation source can be useful, e.g., for
relatively thin piles of materials, e.g., less than 0.5 inch, e.g.,
less than 0.4 inch, 0.3 inch, 0.2 inch, or less than 0.1 inch. In
some embodiments, the energy of each electron of the electron beam
is from about 0.3 MeV to about 2.0 MeV (million electron volts),
e.g., from about 0.5 MeV to about 1.5 MeV, or from about 0.7 MeV to
about 1.25 MeV.
[0202] Electron beam irradiation devices may be procured
commercially from Ion Beam Applications, Louvain-la-Neuve, Belgium
or the Titan Corporation, San Diego, Calif. Typical electron
energies can be 1 MeV, 2 MeV, 4.5 MeV, 7.5 MeV, or 10 MeV. Typical
electron beam irradiation device power can be 1 kW, 5 kW, 10 kW, 20
kW, 50 kW, 100 kW, 250 kW, or 500 kW. The level of depolymerization
of the feedstock depends on the electron energy used and the dose
applied, while exposure time depends on the power and dose. Typical
doses may take values of 1 kGy, 5 kGy, 10 kGy, 20 kGy, 50 kGy, 100
kGy, or 200 kGy.
Ion Particle Beams
[0203] Particles heavier than electrons can be utilized to
irradiate materials, such as carbohydrates or materials that
include carbohydrates, e.g., cellulosic materials, lignocellulosic
materials, starchy materials, or mixtures of any of these and
others described herein. For example, protons, helium nuclei, argon
ions, silicon ions, neon ions carbon ions, phosphorus ions, oxygen
ions or nitrogen ions can be utilized. In some embodiments,
particles heavier than electrons can induce higher amounts of chain
scission (relative to lighter particles). In some instances,
positively charged particles can induce higher amounts of chain
scission than negatively charged particles due to their
acidity.
[0204] Heavier particle beams can be generated, e.g., using linear
accelerators or cyclotrons. In some embodiments, the energy of each
particle of the beam is from about 1.0 MeV/atomic unit to about
6,000 MeV/atomic unit, e.g., from about 3 MeV/atomic unit to about
4,800 MeV/atomic unit, or from about 10 MeV/atomic unit to about
1,000 MeV/atomic unit.
[0205] In certain embodiments, ion beams used to irradiate
carbon-containing materials, e.g., biomass materials, can include
more than one type of ion. For example, ion beams can include
mixtures of two or more (e.g., three, four or more) different types
of ions. Exemplary mixtures can include carbon ions and protons,
carbon ions and oxygen ions, nitrogen ions and protons, and iron
ions and protons. More generally, mixtures of any of the ions
discussed above (or any other ions) can be used to form irradiating
ion beams. In particular, mixtures of relatively light and
relatively heavier ions can be used in a single ion beam.
[0206] In some embodiments, ion beams for irradiating materials
include positively charged ions. The positively charged ions can
include, for example, positively charged hydrogen ions (e.g.,
protons), noble gas ions (e.g., helium, neon, argon), carbon ions,
nitrogen ions, oxygen ions, silicon atoms, phosphorus ions, and
metal ions such as sodium ions, calcium ions, and/or iron ions.
Without wishing to be bound by any theory, it is believed that such
positively-charged ions behave chemically as Lewis acid moieties
when exposed to materials, initiating and sustaining cationic
ring-opening chain scission reactions in an oxidative
environment.
[0207] In certain embodiments, ion beams for irradiating materials
include negatively-charged ions. Negatively charged ions can
include, for example, negatively charged hydrogen ions (e.g.,
hydride ions), and negatively charged ions of various relatively
electronegative nuclei (e.g., oxygen ions, nitrogen ions, carbon
ions, silicon ions, and phosphorus ions). Without wishing to be
bound by any theory, it is believed that such negatively-charged
ions behave chemically as Lewis base moieties when exposed to
materials, causing anionic ring-opening chain scission reactions in
a reducing environment.
[0208] In some embodiments, beams for irradiating materials can
include neutral atoms. For example, any one or more of hydrogen
atoms, helium atoms, carbon atoms, nitrogen atoms, oxygen atoms,
neon atoms, silicon atoms, phosphorus atoms, argon atoms, and iron
atoms can be included in beams that are used for irradiation of
biomass materials. In general, mixtures of any two or more of the
above types of atoms (e.g., three or more, four or more, or even
more) can be present in the beams.
[0209] In certain embodiments, ion beams used to irradiate
materials include singly charged ions such as one or more of
H.sup.+, H.sup.-, He.sup.+, Ne.sup.+, Ar.sup.+, C.sup.+, C.sup.-,
O.sup.+, O.sup.-, N.sup.+, N.sup.-, Si.sup.+, Si.sup.-, P.sup.+,
P.sup.-, Na.sup.+, Ca.sup.+, and Fe.sup.+. In some embodiments, ion
beams can include multiply-charged Ions such as .sup.+, C.sup.2+,
C.sup.3+, C.sup.4+, N.sup.3+, N.sup.5+, N.sup.5-, N3.sup.-,
O.sup.+2, O.sup.2-, O.sub.2.sup.2-, Si.sup.2+, Si.sup.4+,
Si.sup.2-, and Si.sup.4-. In general, the ion beams can also
include more complex polynuclear ions that bear multiple positive
or negative charges. In certain embodiments, by virtue of the
structure of the polynuclear ion, the positive or negative charges
can be effectively distributed over substantially the entire
structure of the ions. In some embodiments, the positive or
negative charges can be somewhat localized over portions of the
structure of the ions.
Electromagnetic Radiation
[0210] In embodiments in which the irradiating is performed with
electromagnetic radiation, the electromagnetic radiation can have,
e.g., energy per photon (in electron volts) of greater than
10.sup.2 eV, e.g., greater than 10.sup.3, 10.sup.4, 10.sup.5,
10.sup.6, or even greater than 10.sup.7 eV. In some embodiments,
the electromagnetic radiation has energy per photon of between
10.sup.4 and 10.sup.7, e.g., between 10.sup.5 and 10.sup.6 eV. The
electromagnetic radiation can have a frequency of, e.g., greater
than 10.sup.16 Hz, greater than 10.sup.17 Hz, 10.sup.18, 10.sup.19,
10.sup.20, or even greater than 10.sup.21 Hz. In some embodiments,
the electromagnetic radiation has a frequency of between 10.sup.18
and 10.sup.22 Hz, e.g., between 10.sup.19 to 10.sup.21 Hz.
[0211] In some embodiments, the irradiating (with any radiation
source or a combination of sources) is performed until the material
receives a dose of at least 0.25 Mrad, e.g., at least 1.0 Mrad, at
least 2.5 Mrad, at least 5.0 Mrad, or at least 10.0 Mrad. In some
embodiments, the irradiating is performed until the material
receives a dose of between 1.0 Mrad and 6.0 Mrad, e.g., between 1.5
Mrad and 4.0 Mrad. In some embodiments, the irradiating is
performed at a dose rate of between 5.0 and 1500.0 kilorads/hour,
e.g., between 10.0 and 750.0 kilorads/hour or between 50.0 and
350.0 kilorads/hours.
[0212] In some embodiments, two or more radiation sources are used,
such as two or more ionizing radiations. For example, samples can
be treated, in any order, with a beam of electrons, followed by
gamma radiation and UV light having wavelengths from about 100 nm
to about 280 nm. In some embodiments, samples are treated with
three ionizing radiation sources, such as a beam of electrons,
gamma radiation, and energetic UV light.
[0213] One or more sonication processing sequences can be used to
process materials from a wide variety of different sources to
extract useful substances from the materials, and to provide
partially degraded organic material (when organic materials are
employed) which functions as input to further processing steps
and/or sequences. Sonication can reduce the molecular weight and/or
crystallinity of the materials, such as one or more of any of the
materials described herein, e.g., one or more carbohydrate sources,
such as cellulosic or lignocellulosic materials, or starchy
materials.
[0214] In one method, a first material that includes cellulose
having a first number average molecular weight (MN1) is dispersed
in a medium, such as water, and sonicated and/or otherwise
cavitated, to provide a second material that includes cellulose
having a second number average molecular weight (MN2) lower than
the first number average molecular weight. The second material (or
the first and second material in certain embodiments) can be
combined with a microorganism (with or without enzyme treatment)
that can utilize the second and/or first material to produce a
useful intermediate that is or includes hydrogen, an alcohol, an
organic acid, a hydrocarbon or mixtures of any of these.
[0215] Since the second material has cellulose having a reduced
molecular weight relative to the first material, and in some
instances, a reduced crystallinity as well, the second material is
generally more dispersible, swellable, and/or soluble in a solution
containing the microorganism, e.g., at a concentration of greater
than 10.sup.6 microorganisms/mL. These properties make the second
material more susceptible to chemical, enzymatic, and/or microbial
attack relative to the first material, which can greatly improve
the production rate and/or production level of a desired product,
e.g., ethanol or other alcohol. Sonication can also sterilize the
materials, but should not be used while the microorganisms are
supposed to be alive.
[0216] In some embodiments, the second number average molecular
weight (M.sub.N2) is lower than the first number average molecular
weight (M.sub.N1) by more than about 10 percent, e.g., 15, 20, 25,
30, 35, 40, 50 percent, 60 percent, or even more than about 75
percent. In some instances, the second material has cellulose that
has as crystallinity (C.sub.2) that is lower than the crystallinity
(C.sub.1) of the cellulose of the first material. For example,
(C.sub.2) can be lower than (C.sub.1) by more than about 10
percent, e.g., 15, 20, 25, 30, 35, 40, or even more than about 50
percent.
[0217] In some embodiments, the starting crystallinity index (prior
to sonication) is from about 40 to about 87.5 percent, e.g., from
about 50 to about 75 percent or from about 60 to about 70 percent,
and the crystallinity index after sonication is from about 10 to
about 50 percent, e.g., from about 15 to about 45 percent or from
about 20 to about 40 percent. However, in certain embodiments,
e.g., after extensive sonication, it is possible to have a
crystallinity index of lower than 5 percent. In some embodiments,
the material after sonication is substantially amorphous.
[0218] In some embodiments, the starting number average molecular
weight (prior to sonication) is from about 200,000 to about
3,200,000, e.g., from about 250,000 to about 1,000,000 or from
about 250,000 to about 700,000, and the number average molecular
weight after sonication is from about 50,000 to about 200,000,
e.g., from about 60,000 to about 150,000 or from about 70,000 to
about 125,000. However, in some embodiments, e.g., after extensive
sonication, it is possible to have a number average molecular
weight of less than about 10,000 or even less than about 5,000.
[0219] In some embodiments, the second material can have a level of
oxidation (O.sub.2) that is higher than the level of oxidation (01)
of the first material. A higher level of oxidation of the material
can aid in its dispersability, swellability and/or solubility,
further enhancing the material's susceptibility to chemical,
enzymatic or microbial attack. In some embodiments, to increase the
level of the oxidation of the second material relative to the first
material, the sonication is performed in an oxidizing medium,
producing a second material that is more oxidized than the first
material. For example, the second material can have more hydroxyl
groups, aldehyde groups, ketone groups, ester groups or carboxylic
acid groups, which can increase its hydrophilicity.
[0220] In some embodiments, the sonication medium is an aqueous
medium. If desired, the medium can include an oxidant, such as a
peroxide (e.g., hydrogen peroxide), a dispersing agent and/or a
buffer. Examples of dispersing agents include ionic dispersing
agents, e.g., sodium lauryl sulfate, and non-ionic dispersing
agents, e.g., poly (ethylene glycol). In other embodiments, the
sonication medium is non-aqueous. For example, the sonication can
be performed in a hydrocarbon, e.g., toluene or heptane, an ether,
e.g., diethyl ether or tetrahydrofuran, or even in a liquefied gas
such as argon, xenon, or nitrogen.
Pyrolysis
[0221] One or more pyrolysis processing sequences can be used to
process carbon containing materials from a wide variety of
different sources to extract useful substances from the materials,
and to provide partially degraded materials which function as input
to further processing steps and/or sequences.
[0222] In one example, a first material that includes cellulose
having a first number average molecular weight (M.sub.N1) is
pyrolyzed, e.g., by heating the first material in a tube furnace
(in the presence or absence of oxygen), to provide a second
material that includes cellulose having a second number average
molecular weight (M.sub.N2) lower than the first number average
molecular weight. The second material (or the first and second
material in certain embodiments) is/are combined with a
microorganism (with or without acid or enzymatic hydrolysis) that
can utilize the second and/or first material to produce a useful
intermediate that is or includes hydrogen, an alcohol (e.g.,
ethanol or butanol, such as n-, sec or t-butanol), an organic acid,
a hydrocarbon or mixtures of any of these.
[0223] Since the second material has cellulose having a reduced
molecular weight relative to the first material, and in some
instances, a reduced crystallinity as well, the second material is
generally more dispersible, swellable and/or soluble in a solution
containing the microorganism, e.g., at a concentration of greater
than 10.sup.6 microorganisms/mL. These properties make the second
material more susceptible to chemical, enzymatic and/or microbial
attack relative to the first material, which can greatly improve
the production rate and/or production level of a desired product,
e.g., ethanol or other alcohol. Pyrolysis can also sterilize the
first and second materials. In some embodiments, the second number
average molecular weight (M.sub.N2) is lower than the first number
average molecular weight (M.sub.N1) by more than about 10 percent,
e.g., 15, 20, 25, 30, 35, 40, 50 percent, 60 percent, or even more
than about 75 percent.
[0224] In some instances, the second material has cellulose that
has as crystallinity (C.sub.2) that is lower than the crystallinity
(C.sub.1) of the cellulose of the first material. For example,
(C.sub.2) can be lower than (C.sub.1) by more than about 10
percent, e.g., 15, 20, 25, 30, 35, 40, or even more than about 50
percent.
[0225] In some embodiments, the starting crystallinity (prior to
pyrolysis) is from about 40 to about 87.5 percent, e.g., from about
50 to about 75 percent or from about 60 to about 70 percent, and
the crystallinity index after pyrolysis is from about 10 to about
50 percent, e.g., from about 15 to about 45 percent or from about
20 to about 40 percent. However, in certain embodiments, e.g.,
after extensive pyrolysis, it is possible to have a crystallinity
index of lower than 5 percent. In some embodiments, the material
after pyrolysis is substantially amorphous.
[0226] In some embodiments, the starting number average molecular
weight (prior to pyrolysis) is from about 200,000 to about
3,200,000, e.g., from about 250,000 to about 1,000,000 or from
about 250,000 to about 700,000, and the number average molecular
weight after pyrolysis is from about 50,000 to about 200,000, e.g.,
from about 60,000 to about 150,000 or from about 70,000 to about
125,000. However, in some embodiments, e.g., after extensive
pyrolysis, it is possible to have a number average molecular weight
of less than about 10,000 or even less than about 5,000.
[0227] In some embodiments, the second material can have a level of
oxidation (O.sub.2) that is higher than the level of oxidation (01)
of the first material. A higher level of oxidation of the material
can aid in its dispersability, swellability and/or solubility,
further enhancing the materials susceptibility to chemical,
enzymatic or microbial attack. In some embodiments, to increase the
level of the oxidation of the second material relative to the first
material, the pyrolysis is performed in an oxidizing environment,
producing a second material that is more oxidized than the first
material. For example, the second material can have more hydroxyl
groups, aldehyde groups, ketone groups, ester groups or carboxylic
acid groups, which can increase its hydrophilicity.
[0228] In some embodiments, the pyrolysis of the materials is
continuous. In other embodiments, the material is pyrolyzed for a
pre-determined time, and then allowed to cool for a second
pre-determined time before pyrolyzing again.
Oxidation
[0229] One or more oxidative processing sequences can be used to
process carbon containing materials from a wide variety of
different sources to extract useful substances from the materials,
and to provide partially degraded and/or altered material which
functions as input to further processing steps and/or
sequences.
[0230] In one method, a first material that includes cellulose
having a first number average molecular weight (M.sub.N1) and
having a first oxygen content (O.sub.2) is oxidized, e.g., by
heating the first material in a stream of air or oxygen-enriched
air, to provide a second material that includes cellulose having a
second number average molecular weight (M.sub.N2) and having a
second oxygen content (02) higher than the first oxygen content
(O.sub.2).Such materials can also be combined with a solid and/or a
liquid. The liquid and/or solid can include a microorganism, e.g.,
a bacterium, and/or an enzyme. For example, the bacterium and/or
enzyme can work on the cellulosic or lignocellulosic material to
produce a fuel, such as ethanol, or a coproduct, such as a protein.
Fuels and coproducts are described in FIBROUS MATERIALS AND
COMPOSITES," U.S. Ser. No. 11/453,951, filed Jun. 15, 2006. The
entire contents of each of the foregoing applications are
incorporated herein by reference.
[0231] In some embodiments, the second number average molecular
weight is not more 97 percent lower than the first number average
molecular weight, e.g., not more than 95 percent, 90, 85, 80, 75,
70, 65, 60, 55, 50, 45, 40, 30, 20, 12.5, 10.0, 7.5, 5.0, 4.0, 3.0,
2.5, 2.0 or not more than 1.0 percent lower than the first number
average molecular weight. The amount of reduction of molecular
weight will depend upon the application. For example, in some
preferred embodiments that provide composites, the second number
average molecular weight is substantially the same as the first
number average molecular weight. In other applications, such as
making ethanol or another fuel or coproduct, a higher amount of
molecular weight reduction is generally preferred.
[0232] In some embodiments in which the materials are used to make
fuel or coproduct, the starting number average molecular weight
(prior to oxidation) is from about 200,000 to about 3,200,000,
e.g., from about 250,000 to about 1,000,000 or from about 250,000
to about 700,000, and the number average molecular weight after
oxidation is from about 50,000 to about 200,000, e.g., from about
60,000 to about 150,000 or from about 70,000 to about 125,000.
However, in some embodiments, e.g., after extensive oxidation, it
is possible to have a number average molecular weight of less than
about 10,000 or even less than about 5,000.
[0233] In some embodiments, the second oxygen content is at least
about five percent higher than the first oxygen content, e.g., 7.5
percent higher, 10.0 percent higher, 12.5 percent higher, 15.0
percent higher or 17.5 percent higher. In some preferred
embodiments, the second oxygen content is at least about 20.0
percent higher than the first oxygen content of the first material.
Oxygen content is measured by elemental analysis by pyrolyzing a
sample in a furnace operating at 1300.degree. C. or higher. A
suitable elemental analyzer is the LECO CHNS-932 analyzer with a
VTF-900 high temperature pyrolysis furnace. Generally, oxidation of
a material occurs in an oxidizing environment. For example, the
oxidation can be affected or aided by pyrolysis in an oxidizing
environment, such as in air or argon enriched in air. To aid in the
oxidation, various chemical agents, such as oxidants, acids or
bases can be added to the material prior to or during oxidation.
For example, a peroxide (e.g., benzoyl peroxide) can be added prior
to oxidation. Some oxidative methods of reducing recalcitrance in a
carbon-containing material, such as coal or cellulosic or
lignocellulosic materials, employ Fenton or Fenten-type chemistry.
Such methods are disclosed, for example, in U.S. Provisional
Application No. 61/139,473, filed Dec. 19, 2008, the complete
disclosure of which is incorporated herein by reference.
[0234] Exemplary oxidants include peroxides, such as hydrogen
peroxide and benzoyl peroxide, persulfates, such as ammonium
persulfate, activated forms of oxygen, such as ozone,
permanganates, such as potassium permanganate, perchlorates, such
as sodium perchlorate, and hypochlorites, such as sodium
hypochlorite (household bleach). In some situations, pH is
maintained at or below about 5.5 during contact, such as between 1
and 5, between 2 and 5, between 2.5 and 5 or between about 3 and 5.
Conditions can also include a contact period of between 2 and 12
hours, e.g., between 4 and 10 hours or between 5 and 8 hours. In
some instances, conditions include not exceeding 300.degree. C.,
e.g., not exceeding 250, 200, 150, 100 or 50.degree. C. In special
desirable instances, the temperature remains substantially ambient,
e.g., at or about 20-25.degree. C.
[0235] In some desirable embodiments, the one or more oxidants are
applied to a first cellulosic or lignocellulosic material and the
one or more compounds as a gas, such as by generating ozone in-situ
by irradiating the first cellulosic or lignocellulosic material and
the one or more compounds through air with a beam of particles,
such as electrons. In particular desirable embodiments, a first
cellulosic or lignocellulosic material is firstly dispersed in
water or an aqueous medium that includes the one or more compounds
dispersed and/or dissolved therein, water is removed after a soak
time (e.g., loose and free water is removed by filtration), and
then the one or more oxidants are applied to the combination as a
gas, such as by generating ozone in-situ by irradiating the first
cellulosic or lignocellulosic and the one or more compounds through
air with a beam of particles, such as electrons (e.g., each being
accelerated by a potential difference of between 3 MeV and 10 MeV).
Soaking can open up interior portions to oxidation.
[0236] In some embodiments, the mixture includes one or more
compounds and one or more oxidants, and a mole ratio of the one or
more compounds to the one or more oxidants is from about 1:1000 to
about 1:25, such as from about 1:500 to about 1:25 or from about
1:100 to about 1:25.
[0237] In some desirable embodiments, the mixture further includes
one or more hydroquinones, such as 2,5-dimethoxyhydroquinone (DMHQ)
and/or one or more benzoquinones, such as
2,5-dimethoxy-1,4-benzoquinone (DMBQ), which can aid in electron
transfer reactions.
[0238] In some desirable embodiments, the one or more oxidants are
electrochemically-generated in-situ. For example, hydrogen peroxide
and/or ozone can be electrochemically produced within a contact or
reaction vessel.
[0239] Other Processes to Solubilize, Reduce Recalcitrance or to
Functionalize
[0240] Any of the processes of this paragraph can be used alone
without any of the processes described herein, or in combination
with any of the processes described herein (in any order): steam
explosion, acid treatment (including concentrated and dilute acid
treatment with mineral acids, such as sulfuric acid, hydrochloric
acid and organic acids, such as trifluoroacetic acid), base
treatment (e.g., treatment with lime or sodium hydroxide), UV
treatment, screw extrusion treatment (see, e.g., U.S. Patent
Application Ser. No. 61/073,530, filed Nov. 18, 2008, solvent
treatment (e.g., treatment with ionic liquids) and freeze grinding
or freeze milling (see, e.g., U.S. Patent Application Ser. No.
61/081,709). Further detail on processing of biomass can be found
in U.S. Pat. No. 9,342,294, issued May 31, 2016, the contents of
which are incorporated in its entirety by reference.
[0241] Combinations of Irradiating, Sonicating, and Oxidizing
Devices
[0242] In some embodiments, it may be advantageous to combine two
or more separate irradiation, sonication, pyrolization, and/or
oxidation devices into a single hybrid machine. For such a hybrid
machine, multiple processes may be performed in close juxtaposition
or even simultaneously, with the benefit of increasing pretreatment
throughput and potential cost savings.
[0243] For example, consider the electron beam irradiation and
sonication processes. Each separate process is effective in
lowering the mean molecular weight of cellulosic material by an
order of magnitude or more, and by several orders of magnitude when
performed serially.
[0244] Both irradiation and sonication processes can be applied
using a hybrid electron beam/sonication device. For example, a
hybrid electron beam/sonication device can include a shallow pool
(depth .about.3-5 cm) of a slurry of cellulosic material dispersed
in an aqueous, oxidant medium, such as hydrogen peroxide or
carbamide peroxide. Hybrid device has an energy source, which
powers both electron beam emitter and sonication horns. Electron
beam emitter generates electron beams which pass through an
electron beam aiming device to impact the slurry containing
cellulosic material. On either side of the electron beam emitter
are sonication horns, which deliver ultrasonic wave energy to the
slurry. The sonication horns end in a detachable end-piece that is
in contact with the slurry. Further detail on processing of biomass
can be found in U.S. Pat. No. 9,342,294, issued May 31, 2016, the
contents of which are incorporated in its entirety by
reference.
[0245] A further benefit of such a simultaneous electron beam and
ultrasound process is that the two processes have complementary
results. With electron beam irradiation alone, an insufficient dose
may result in cross-linking of some of the polymers in the
cellulosic material, which lowers the efficiency of the overall
depolymerization process. Lower doses of electron beam irradiation
and/or ultrasound radiation may also be used to achieve a similar
degree of depolymerization as that achieved using electron beam
irradiation and sonication separately.
[0246] An electron beam device can also be combined with one or
more of high-frequency, rotor-stator devices, which can be used as
an alternative to ultrasonic energy devices, and performs a similar
function.
[0247] Further combinations of devices are also possible. For
example, an ionizing radiation device that produces gamma radiation
emitted from, e.g., .sup.60Co pellets, can be combined with an
electron beam source and/or an ultrasonic wave source. Shielding
requirements may be more stringent in this case.
[0248] The radiation devices for pretreating biomass discussed
above can also be combined with one or more devices that perform
one or more pyrolysis processing sequences. Such a combination may
again have the advantage of higher throughput. Nevertheless,
caution must be observed, as there may be conflicting requirements
between some radiation processes and pyrolysis. For example,
ultrasonic radiation devices may require the feedstock be immersed
in a liquid oxidizing medium. On the other hand, as discussed
previously, it may be advantageous for a sample of feedstock
undergoing pyrolysis to be of a particular moisture content. In
this case, the new systems automatically measure and monitor for a
particular moisture content and regulate the same. Further, some or
all of the above devices, especially the pyrolysis device, can be
combined with an oxidation device as discussed previously.
Saccharification
[0249] In order to convert the feedstock to fermentable sugars, the
cellulose in the feedstock is hydrolyzed by a saccharifying agent,
e.g., an enzyme, a process referred to as saccharification. The
materials that include the cellulose are treated with the enzyme,
10 e.g., by combining the material and the enzyme in a solvent,
e.g., in an aqueous solution. Enzymes and biomass-destroying
organisms that break down biomass, such as the cellulose and/or the
lignin portions of the biomass, contain or manufacture various
cellulolytic enzymes (cellulases), ligninases or various small
molecule biomass destroying metabolites. These enzymes may be a
complex of enzymes that act 15 synergistically to degrade
crystalline cellulose or the lignin portions of biomass.
[0250] Examples of cellulolytic enzymes include: endoglucanases,
cellobiohydrolases, and cello biases (.about.-glucosidases). A
cellulosic substrate is initially hydrolyzed by endoglucanases at
random locations producing oligomeric intermediates. These
intermediates are then substrates for exo-splitting glucanases such
as cellobiohydrolase to produce cellobiose from the ends of the
cellulose polymer. Cellobiose is a water-soluble 1,4-linked dimer
of glucose. Finally, cellobiase cleaves cellobiose to yield
glucose.
[0251] The saccharification process can be partially or completely
performed in a tank 30 (e.g., a tank having a volume of at least
4000, 40,000, 400,000, or 1,000,000 L) in a manufacturing plant,
and/or can be partially or completely performed in transit, e.g.,
in a rail car, tanker truck, or in a supertanker or the hold of a
ship. The time required for complete saccharification will depend
on the process conditions and the feedstock and enzyme used. If
saccharification is performed in a manufacturing plant under
controlled conditions, the cellulose may be substantially entirely
converted to glucose in about 12-96 hours. If saccharification is
performed partially or completely in transit, saccharification may
take longer.
[0252] It is generally preferred that the tank contents be mixed
during saccharification, e.g., using jet mixing as described in
U.S. Provisional Application No. 61/218,832, the full disclosure of
which is incorporated by reference herein. The addition of
surfactants can enhance the rate of saccharification. Examples of
surfactants include non-ionic surfactants, such as a Tween.RTM. 20
or Tween.RTM. 80 polyethylene glycol surfactants, ionic
surfactants, or amphoteric surfactants.
[0253] A cellulase is capable of degrading biomass and may be of
fungal or bacterial origin. Suitable cellulolytic enzymes include
cellulases from the genera Bacillus, Pseudomonas, Humicola,
Fusarium, Thielavia, Acremonium, Chrysosporium and Trichoderma, and
include species of Humicola, Coprinus, Thielavia, Fusarium,
Myceliophthora, Acremonium, Cephalosporium, Scytalidium,
Penicillium or Aspergillus (see, e.g., EP 458162), especially those
produced by a strain selected from the species Humicola insolens
(reclassified as Scytalidium thermophilum, see, e.g., U.S. Pat. No.
4,435,307), Coprinus cinereus, Fusarium oxysporum, Myceliophthora
thermophila, Meripilus giganteus, Thielavia terrestris, Acremonium
sp., Acremonium persicinum, Acremonium, Acremonium brachypenium,
Acremonium dichromosporum, Acremonium obclavatum, Acremonium
pinkertoniae, Acremonium roseogriseum, Acremonium incoloratum, and
Acremonium furatum; preferably from the species Humicola insolens
DSM 1800, Fusarium oxysporum DSM 2672, Myceliophthora thermophila
CBS 117.65, Cephalosporium sp. RYM-202, Acremonium sp. CBS 478.94,
Acremonium sp. CBS 265.95, Acremonium persicinum CBS 169.65,
Acremonium AHU 9519, Cephalosporium sp. CBS 535.71, Acremonium
brachypenium CBS 866.73, Acremonium dichromosporum CBS 683.73,
Acremonium obclavatum CBS 311.74, Acremonium pinkertoniae CBS
157.70, Acremonium roseogriseum CBS 134.56, Acremonium incoloratum
CBS 146.62, and Acremonium furatum CBS 299.70H. Cellulolytic
enzymes may also be obtained from Chrysosporium, preferably a
strain of Chrysosporium lucknowense. Additionally, Trichoderma
(particularly Trichoderma viride, Trichoderma reesei, and
Trichoderma koningii), alkalophilic Bacillus (see, for example,
U.S. Pat. No. 3,844,890 and EP 458162), and Streptomyces (see,
e.g., EP 458162) may be used. The bacterium, Saccharophagus
degradans, produces a mixture of enzymes capable of degrading a
range of cellulosic materials and may also be used in this
process.
[0254] Enzymes which break down biomass, such as cellulose, to
lower molecular weight carbohydrate-containing materials, such as
glucose, during saccharification are referred to as cellulolytic
enzymes or cellulase. These enzymes may be a complex of enzymes
that act synergistically to degrade crystalline cellulose. Examples
of cellulolytic enzymes include: endoglucanases,
cellobiohydrolases, and cellobiases (.beta.-glucosidases). A
cellulosic substrate is initially hydrolyzed by endoglucanases at
random locations producing oligomeric intermediates. These
intermediates are then substrates for exo-splitting glucanases such
as cellobiohydrolase to produce cellobiose from the ends of the
cellulose polymer. Cellobiose is a water-soluble .beta.-1,4-linked
dimer of glucose. Finally, cellobiase cleaves cellobiose to yield
glucose.
[0255] Anaerobic cellulolytic bacteria have also been isolated from
soil, e.g., a novel cellulolytic species of Clostiridium,
Clostridium phytofermentans sp. nov. (see Leschine et. al,
International Journal of Systematic and Evolutionary Microbiology
(2002), 52, 1155-1160).
[0256] Cellulolytic enzymes using recombinant technology can also
be used (see, e.g., WO 2007/071818 and WO 2006/110891).
[0257] The cellulolytic enzymes used can be produced by
fermentation of the above-noted microbial strains on a nutrient
medium containing suitable carbon and nitrogen sources and
inorganic salts, using procedures known in the art (see, e.g.,
Bennett, J. W. and LaSure, L. (eds.), More Gene Manipulations in
Fungi, Academic Press, CA 1991). Suitable media are available from
commercial suppliers or may be prepared according to published
compositions (e.g., in catalogues of the American Type Culture
Collection). Temperature ranges and other conditions suitable for
growth and cellulase production are known in the art (see, e.g.,
Bailey, J. E., and Ollis, D. F., Biochemical Engineering
Fundamentals, McGraw-Hill Book Company, N Y, 1986).
[0258] Treatment of cellulose with cellulase is usually carried out
at temperatures between 30.degree. C. and 65.degree. C. Cellulases
are active over a range of pH of about 3 to 7. A saccharification
step may last up to 120 hours. The cellulase enzyme dosage achieves
a sufficiently high level of cellulose conversion. For example, an
appropriate cellulase dosage is typically between 5.0 and 50 Filter
Paper Units (FPU or IU) per gram of cellulose. The FPU is a
standard measurement and is defined and measured according to Ghose
(1987, Pure and Appl. Chem. 59:257-268).
[0259] In certain embodiments, the concentration of the resulting
glucose solution can be relatively high, e.g., greater than 40%, or
greater than 50, 60, 70, 80, 90 or even greater than 95% by weight.
This reduces the volume to be shipped, if saccharification and
fermentation are performed at different locations, and also
inhibits microbial growth in the solution. However, lower
concentrations may be used, in which case it may be desirable to
add an antimicrobial additive, e.g., a broad spectrum antibiotic,
in a low concentration, e.g., 50 to 150 ppm. Other suitable
antibiotics include amphotericin B, 20 ampicillin, chloramphenicol,
ciprofloxacin, gentamicin, hygromycin B, kanamycin, neomycin,
penicillin, puromycin, streptomycin. Antibiotics will inhibit
growth of microorganisms during transport and storage, and can be
used at appropriate concentrations, e.g., between 15 and 1000 ppm
by weight, e.g., between 25 and 500 ppm, or between 50 and 150 ppm.
If desired, an antibiotic can be included even if the sugar
concentration is relatively high.
[0260] A relatively high concentration solution can be obtained by
limiting the amount of water added to the feedstock with the
enzyme. The concentration can be controlled, e.g., by controlling
how much saccharification takes place. For example, concentration
can be increased by adding more feedstock to the solution. In order
to keep the sugar that is being produced in solution, a surfactant
can be added, e.g., one of those discussed above. Solubility can
also be increased by increasing the temperature of the solution.
For example, the solution can be maintained at a temperature of
40-50.degree. C., 60-80.degree. C., or even higher.
[0261] In some embodiments, the feedstock is processed to convert
it to a convenient and concentrated solid material, e.g., in a
powdered, granulate or particulate form. The concentrated material
can be in a purified, or a raw or crude form. The concentrated form
can have, for example, a total sugar concentration of between about
90 percent by weight and about 100 percent by weight, e.g., 92, 94,
96 or 98 percent by weight sugar. Such a form can be particularly
cost effective to ship, e.g., to a bioprocessing facility, such as
a biofuel manufacturing plant. Such a form can also be advantageous
to store and handle, easier to manufacture and becomes both an
intermediate and a product, providing an option to the biorefinery
as to which products to manufacture.
[0262] In some instances, the powdered, granulate or particulate
material can also include one or more of the materials, e.g.,
additives or chemicals, described herein, such as the food-based
nutrient or nutrient package, a nitrogen source, e.g., urea, a
surfactant, an enzyme, or any microorganism described herein. In
some instances, all materials needed for a bio-process are combined
in the powdered, granulate or particulate material. Such a form can
be a particularly convenient form for transporting to a remote
bioprocessing facility, such as a remote biofuels manufacturing
facility. Such a form can also be advantageous to store and
handle.
[0263] In some instances, the powdered, granulate or particulate
material (with or without added materials, such as additives and
chemicals) can be treated by any of the physical treatments
described in U.S. Ser. No. 12/429,045, incorporated by reference
above. For example, irradiating the powdered, granulate or
particulate material can increase its solubility and can sterilize
the material so that a bioproces sing facility can integrate the
material into their process directly as may be required for a
contemplated intermediate or product.
[0264] In certain instances, the powdered, granulate or particulate
material (with or without added materials, such as additives and
chemicals) can be carried in a structure or a carrier for ease of
transport, storage or handling. For example, the structure or
carrier can include or incorporate a bag or liner, such as a
degradable bag or liner. Such a form can be particularly useful for
adding directly to a bioprocess system.
[0265] Optionally, the sugar solution can be processed prior to any
fermentation step. For example, a saccharified solution as prepared
by the methods described herein can be purified and/or processed by
filtration (e.g., including rotary vacuum drum filtration),
chromatography (e.g., simulated moving bed chromatography),
electrodialysis including bipolar electrodialysis, crystallization
and combinations of these. Optionally, processing can include
fermenting one sugar in a mixture of two sugars and removal of the
fermentation product, leaving a sugar solution of substantially the
second sugar which can be more easily utilized, for example
isolated and/or fermented (e.g. to a carboxylic acid). Some
exemplary methods for purification and/or processing that can be
utilized are discussed in co-pending U.S. Provisional Application
Ser. Nos. 61/774,775, 61/774,780 and 61/774,761, the disclosures of
which are incorporated herein by reference. In some cases, a
biomass source can provide a higher amount of essentially only one
sugar, for example some paper products, cotton and other biomass
that is almost entirely a glucose source with little if any xylose.
Other biomass sources may provide mostly xylose and/or lignin.
[0266] Fermentation
[0267] Generally, various microorganisms can produce a number of
useful products, such as a fuel, by operating on, e.g., fermenting
the pretreated biomass materials. For example, Natural Force.TM.
Chemistry methods can be used to prepare biomass materials for use
in fermentation. Alcohols, organic acids, hydrocarbons, hydrogen,
proteins or mixtures of any of these materials, for example, can be
produced by fermentation or other processes.
[0268] The microorganism can be a natural microorganism or an
engineered microorganism. For example, the microorganism can be a
bacterium, e.g., a cellulolytic bacterium, a fungus, e.g., a yeast,
a plant or a protist, e.g., an algae, a protozoa or a fungus-like
protist, e.g., a slime mold. When the organisms are compatible,
mixtures of organisms can be utilized.
[0269] To aid in the breakdown of the materials that include the
cellulose, one or more enzymes, e.g., a cellulolytic enzyme can be
utilized. In some embodiments, the materials that include the
cellulose are first treated with the enzyme, e.g., by combining the
material and the enzyme in an aqueous solution. This material can
then be combined with the microorganism. In other embodiments, the
materials that include the cellulose, the one or more enzymes and
the microorganism are combined at the concurrently, e.g., by
combining in an aqueous solution.
[0270] Also, to aid in the breakdown of the materials that include
the cellulose, the materials can be treated post irradiation with
heat, a chemical (e.g., mineral acid, base or a strong oxidizer
such as sodium hypochlorite), and/or an enzyme.
[0271] During the fermentation, sugars released from cellulolytic
hydrolysis or the saccharification step, are fermented to, e.g.,
ethanol, by a fermenting microorganism such as yeast. Suitable
fermenting microorganisms have the ability to convert
carbohydrates, such as glucose, xylose, arabinose, mannose,
galactose, oligosaccharides or polysaccharides into fermentation
products. Fermenting microorganisms include strains of the genus
Saccharomyces spp. e.g., Saccharomyces cerevisiae (baker's yeast),
Saccharomyces distaticus, Saccharomyces uvarum; the genus
Kluyveromyces, e.g., species Kluyveromyces marxianus, Kluyveromyces
fragilis; the genus Candida, e.g., Candida pseudotropicalis, and
Candida brassicae, Pichia stipitis (a relative of Candida shehatae,
the genus Clavispora, e.g., species Clavispora lusitaniae and
Clavispora opuntiae the genus Pachysolen, e.g., species Pachysolen
tannophilus, the genus Bretannomyces, e.g., species Bretannomyces
clausenii (Philippidis, G. P., 1996, Cellulose bioconversion
technology, in Handbook on Bioethanol: Production and Utilization,
Wyman, C. E., ed., Taylor & Francis, Washington, D.C.,
179-212).
[0272] Commercially available yeast includes, for example, Red
Star.RTM./Lesaffre Ethanol Red (available from Red Star/Lesaffre,
USA) FALI.RTM. (available from Fleischmann's Yeast, a division of
Burns Philip Food Inc., USA), SUPERSTART.RTM. (available from
Alltech, now Lallemand), GERT STRAND.RTM. (available from Gert
Strand AB, Sweden) and FERMOL.RTM. (available from DSM
Specialties).
[0273] Bacteria that can ferment biomass to ethanol and other
products include, e.g., Zymomonas mobilis and Clostridium
thermocellum (Philippidis, 1996, supra). Leschine et al.
(International Journal of Systematic and Evolutionary Microbiology
2002, 52, 1155-1160) isolated an anaerobic, mesophilic,
cellulolytic bacterium from forest soil, Clostridium
phytofermentans sp. nov., which converts cellulose to ethanol.
[0274] Fermentation of biomass to ethanol and other products may be
carried out using certain types of thermophilic or genetically
engineered microorganisms, such Thermoanaerobacter species,
including T. mathranii, and yeast species such as Pichia species.
An example of a strain of T. mathranii is A3M4 described in
Sonne-Hansen et al. (Applied Microbiology and Biotechnology 1993,
38, 537-541) or Ahring et al. (Arch. Microbiol. 1997, 168,
114-119). Other microorganisms can produce ethanol from sugars by
fermentation in addition to other products. Examples include
heterolactic acid fermentation in which Leuconostoc bacteria
produce lactate, ethanol and CO.sub.2, mixed acid fermentation
where Escherichia produce ethanol mixed with lactate, acetate,
succinate, formate, CO.sub.2 and H.sub.2, and
[0275] 2,3-Butanediol Fermentation by Enterobacteri Producing
Ethanol, Butanediol, Lactate, Formate, CO.sub.2 and H.sub.2.
[0276] Yeast and Zymomonas bacteria can be used for fermentation or
conversion. The optimum pH for yeast is from about pH 4 to 5, while
the optimum pH for Zymomonas is from about pH 5 to 6. Typical
fermentation times are about 24 to 96 hours with temperatures in
the range of 26.degree. C. to 40.degree. C.; however thermophilic
microorganisms prefer higher temperatures.
[0277] During fermentation, the pH of the fermentation media can be
an important parameter to control. Buffers, for example, phosphate,
sulfate and acetate buffers can help maintain a target pH. Addition
of acids and bases (e. g., ammonium hydroxide, sodium and potassium
hydroxides, acetic acid, sulfuric acid, phosphoric acid, nitric
acids) can also be added before, after and during the fermentation
to maintain and or change or control the pH. During fermentation,
the pH is optimally between about 2 and 8 (e.g., between about 3
and 8, between about 4 and 8, between about 4 and 7). Maintaining
the pH above a critical value, for example above about 3 (e.g.,
above about 3.5, above about 4) by the addition of a base can often
improve the fermentation. This control can be particularly
important while using acidogenic bacteria since the acid products
can lower the pH during the fermentation to values that are toxic
to the organisms.
[0278] The temperature can also be a controlling and important
parameter during fermentation. Optimally the temperature is
maintained between about 20 and 50.degree. C. (e.g., between about
20 and 40.degree. C., between about 30 and 40.degree. C.). In some
instances, lower or higher temperatures from an optimal temperature
can be utilized to induce a desired fermentation phase, e.g.,
acidogenisis, solventogenisis, log growth, sporulation.
[0279] The fermenting microorganism strains can be chosen, which
can predominantly ferment certain types of sugar (such as C5 or C6
sugars) to ethanol effectively can also be used. For example, C5
Fuel.TM., Xyloferm.RTM. (both available from Lallemand), and
CelluX.TM. 4 (available from Leaf-Lesaffre Advanced Fermentations)
can be used to ferment xylose.
[0280] For anaerobic organisms it is preferable to conduct the
fermentation in the absence of oxygen e.g., under a blanket of an
inert gas such as N.sub.2, Ar, He, CO.sub.2 or mixtures thereof.
Additionally, the mixture may have a constant purge of an inert gas
flowing through the tank or bioreactor during part of or all of the
fermentation.
[0281] The fermenting or saccharifying organism can be immobilized
on a support. For example, an application of this process is
described in U.S. Pat. No. 5,563,069. The organism can be supported
on a cellulosic or lignocellulosic material as describe in U.S.
patent Ser. No. 12/782,543 the entire disclosure of which is herein
incorporated by reference.
[0282] Mobile fermenters can be utilized, as described in U.S.
Provisional Patent Application Ser. 60/832,735, now Published
International Application No. WO 2008/011598.
[0283] It can be beneficial to supply additives during
fermentation, for example acids, bases, buffers, amino acids,
vitamins, blackstrap molasses, reinforced Clostridia media (RCM),
metal ions, yeast extract, distillate bottoms, meat extracts,
vegetable extracts, peptones, carbon sources and proteins. For
example, the addition of metal ions of Fe, Mn, Mg, Na, Cu, Zn and
combinations of these can be beneficial. Other additives, for
example, p-aminobenzoic acids, choline, inositol, thiamin, and
albumin can be beneficial.
[0284] A preferred additive that can be utilized is the distillate
bottom from a fermented saccharified lignocellulosic or cellulosic
material (e.g., biomass). For example, the yeast fermentation of a
saccharified material as described herein producing ethanol can be
distilled to produce a distillation bottom. The distillate bottom
containing yeast cells and spent biomass (e.g., lignin,
non-fermented sugars, proteins) can be used as an additive to a
second fermentation. The distillate bottom can be optionally
purified prior to use, for example, by methods described herein
(e.g., rotary vacuum drum filters, simulated moving bed
chromatography and improvements to simulated moving bed
chromatography, filtration, precipitation). The concentration of
solids (e.g., dissolved and/or suspended solids) can be at least
about 5 wt. % (e.g., at least about 10 wt. %, at least about 20 wt.
%, at least about 20 wt. %, at least about 30 wt. %, at least about
40 wt. %, at least about 50 wt. %, at least about 60 wt. %, between
about 10 and 90 wt. %, between about 20 and 60 wt. %). The
distillate bottom be used directly in the distillation or it can be
diluted with a solvent (e.g., water) and used as at least 5 wt. %
distillate bottom to solvent (e.g., at least 10 wt. %, at least 20
wt. %, at least 30 wt. %, at least 40 wt. %, between about 10 and
80 wt. %, between about 10 and 60 wt. %, between about 10 and 50
wt. %, between about 20 and 50 wt. %, between about 20 and 40 wt.
%). The distillation bottom additive can be used in combination
with other additive as herein described and additional sugars
(e.g., glucose and/or xylose).
[0285] Fermentation can be used to provide a variety of products.
Generally, various microorganisms can produce a number of useful
products by operating on, converting, bioconverting, or fermenting
the materials. For example, alcohols, organic acids, hydrocarbons,
hydrogen, proteins, carbohydrates, fats/oils/lipids, amino acids,
vitamins, or mixtures of any of these materials can be produced by
fermentation or other processes.
[0286] In one or more embodiments, the fermentation can produce an
alcohol. Ethanol fermentation, also called alcoholic fermentation,
is a biological process which converts sugars such as glucose,
fructose, and sucrose into cellular energy, producing ethanol and
carbon dioxide as a side-effect. Because yeasts perform this
conversion in the absence of oxygen, alcoholic fermentation is
considered an anaerobic process. Yeast fermentation of various
carbohydrate products is also used to produce the ethanol that can
be used in one or more embodiments to produce gasoline or other
fuels or fuel additives. Ethanol fermentation also produces
unharvested byproducts such as heat, carbon dioxide, food for
livestock, and water.
[0287] In one embodiment, the ethanol generated from
lignocellulosic biomass by the processes described herein can
include other components such as acetone, methanol, n-propanol,
2-methyl propanol, n-butanol, 2-methyl butanol and isopropyl
alcohol. In some embodiments, the ethanol may contain about 0.0001%
to about 0.001% acetone, about 0.001% to about 0.01% acetone, about
0.01% to about 0.1% acetone, about 0.1% to about 1% acetone, or in
a range bounded by any numerical value stated herein above. In some
embodiments, the ethanol may contain about 0.01% to about 0.1%
methanol, about 0.1% to about 1% methanol, about 1% to about 2%
methanol, about 2% to about 3% methanol, about 3% to about 4%
methanol, about 4% to about 5% methanol, about 5% to about 10%
methanol, or in a range bounded by any numerical value stated
herein above. In some embodiments, the ethanol may contain about
0.01% to about 0.05% n-propanol, 0.05% to about 0.1% n-propanol,
about 0.1% to about 0.15% n-propanol, about 0.15% to about 0.2%
n-propanol, about 0.2% to about 0.3% n-propanol, about 0.3% to
about 0.4% n-propanol, about 0.4% to about 0.5% n-propanol, about
0.5% to about 1% n-propanol, about 1% to about 2% n-propanol, or in
a range bounded by any numerical value stated herein above. In some
embodiments, the ethanol may contain about 0.01% to about 0.05%
2-methyl propanol, 0.05% to about 0.1% 2-methyl propanol, about
0.1% to about 0.15% 2-methyl propanol, about 0.15% to about 0.2%
2-methyl propanol, about 0.2% to about 0.3% 2-methyl propanol,
about 0.3% to about 0.4% 2-methyl propanol, about 0.4% to about
0.5% 2-methyl propanol, about 0.5% to about 1% 2-methyl propanol,
about 1% to about 2% 2-methyl propanol, or in a range bounded by
any numerical value stated herein above. In some embodiments, the
ethanol may contain about 0.001% to about 0.005% n-butanol, 0.005%
to about 0.01% n-butanol, about 0.01% to about 0.015% n-butanol,
about 0.015% to about 0.02% n-butanol, about 0.02% to about 0.03%
n-butanol, about 0.03% to about 0.04% n-butanol, about 0.04% to
about 0.05% n-butanol, about 0.05% to about 0.1% n-butanol, about
0.1% to about 0.2% n-butanol, or in a range bounded by any
numerical value stated herein above. In some embodiments, the
ethanol may contain about 0.1% to about 0.15% 2-methyl butanol,
about 0.15% to about 0.2% 2-methyl butanol, about 0.2% to about
0.3% 2-methyl butanol, about 0.3% to about 0.4% 2-methyl butanol,
about 0.4% to about 0.5% 2-methyl butanol, about 0.5% to about 0.6%
2-methyl butanol, about 0.6% to about 0.7% 2-methyl butanol, about
0.7% to about 0.8% 2-methyl butanol, about 0.8% to about 0.9%
2-methyl butanol, about 0.9% to about 1% 2-methyl butanol, about 1%
to about 2% 2-methyl butanol, about 2% to about 3% 2-methyl
butanol, about 3% to about 4% 2-methyl butanol, about 4% to about
5% 2-methyl butanol, or in a range bounded by any numerical value
stated herein above. In some embodiments, the ethanol may contain
about 0.01% to about 0.1% isopropyl alcohol, about 0.1% to about 1%
isopropyl alcohol, about 1% to about 2% isopropyl alcohol, about 2%
to about 3% isopropyl alcohol, about 3% to about 4% isopropyl
alcohol, about 4% to about 5% isopropyl alcohol, about 5% to about
10% isopropyl alcohol, about 10% to about 15% isopropyl alcohol,
about 15% to about 20% isopropyl alcohol, about 20% to about 25%
isopropyl alcohol, or in a range bounded by any numerical value
stated herein above. In some embodiments, the ethanol may contain
about 0.02% acetone, about 0.11 to about 2.5% methanol, about 0.18%
n-propanol, about 0.12% of 2-methyl propanol, about 0.01%
n-butanol, about 0.53% 2-methyl butanol and about 8.5% isopropyl
alcohol.
[0288] In some embodiments, the composition of ethanol described
above is measured by using a Flame Ionization Detector (FID) gas
chromatography method. Other detectors may also be used to analyze
the composition of ethanol derived by the processes described
herein. For example, thermal conductivity detector, catalytic
combustion detector, discharge ionization detector, dry
electrolytic conductivity detector, electron capture detector,
flame photometric detector, atomic emission detector, infrared
detector, mass spectrometer, photoionization detector, pulse
discharge ionization detector, NMR spectrometer and ultraviolet
detector may also be used to analyze the ethanol generated by the
processes described herein. In some embodiments, these detectors
may be used with liquid chromatography.
[0289] FIG. 10 provides a chromatogram analyzing ethanol produced
from cellulosic or lignocellulosic biomass generated by the
processes described herein. It shows that, in some embodiments, the
ethanol produced from cellulosic or lignocellulosic biomass
contains other constituents such acetone, methanol and isopropyl
alcohol (IPA). FIGS. 12A, B provide a chromatogram obtained by
analyzing ethanol produced from lignocellulosic biomass generated
by the processes described in this application by using Flame
Ionization Detector (FID) gas chromatography. It shows that, in
some embodiments, the ethanol from cellulosic and lignocellulosic
biomass studied herein contains other constituents such acetone,
methanol, n-propanol, 2-methyl-propanol, n-butanol, 2-methyl
butanol and isopropyl alcohol (IPA). FIGS. 13A, B provide a Flame
Ionization Detector (FID) gas chromatogram obtained by analyzing
ethanol produced from cane. FIGS. 13A, B show the composition of
ethanol produced from cane. They show that, in some embodiments,
the ethanol from cane does not contain the constituents observed in
ethanol obtained from the cellulosic and lignocellulosic biomass
studied herein. FIGS. 14A, B provide a Flame Ionization Detector
(FID) gas chromatogram obtained by analyzing ethanol produced from
corn. FIGS. 14A, B show the composition of ethanol produced from
corn. They show that in some embodiments, the ethanol from corn
does not contain the constituents observed in ethanol obtained from
the cellulosic and lignocellulosic biomass studied herein. FIGS.
15A, B provide a Flame Ionization Detector (FID) gas chromatogram
obtained by analyzing ethanol produced from grape. FIGS. 15A, B
show the composition of ethanol produced from grape. They show that
in some embodiments, the ethanol from grape does not contain the
constituents observed in ethanol obtained from the cellulosic and
lignocellulosic biomass studied herein. FIGS. 16A, B provide a
Flame Ionization Detector (FID) gas chromatogram obtained by
analyzing ethanol produced from wheat. FIGS. 16A, B show the
composition of ethanol produced from wheat. They show that, in some
embodiments, the ethanol from wheat does not contain the
constituents observed in ethanol obtained from the cellulosic and
lignocellulosic biomass studied herein.
[0290] The ethanol samples in FIGS. 10 and 12A, B to 16A, B were
analyzed using a FID gas chromatography method with a head space
probe and an Agilent DB-FFAP column. Specifically, the carrier gas
used in the column was Helium, and that in the Front Detector FID
included hydrogen and air. The oven was maintained at a temperature
of 55.degree. C., the loop at 90.degree. C., and the transfer line
at 105.degree. C. The pressure in the column was 13.036 psi, and
the flow-rate ranged from 3.52 ml/min to 51.521 ml/min.
[0291] The above studies show that ethanol produced by the
processes described herein can have unique composition and/or
properties, which distinguishes ethanol obtained from one type of
biomass from that derived from another type of biomass. The
examples provided herein are however, not limiting. One can obtain
ethanol of unique composition and/or properties from the processes
described herein from all types of biomass material. Generally, any
biomass material including carbohydrates composed entirely of one
or more saccharide units can be processed to produce ethanol of
unique composition by the methods described herein. The biomass can
be recalcitrant biomass or recalcitrant-reduced biomass. The
biomass material can be cellulosic or lignocellulosic materials, or
starchy materials, such as kernels of corn, grains of rice or other
foods, or materials that are or that include one or more low
molecular weight sugars, such as sucrose or cellobiose. Biomass can
also include paper, paper products, wood, wood-related materials,
particle board, grasses, rice hulls, bagasse, cotton, jute, hemp,
flax, bamboo, sisal, abaca, straw, corn cobs, rice hulls, coconut
hair, algae, seaweed, cotton, synthetic celluloses, or mixtures of
any of these. Fiber sources can also be used, for example,
cellulosic fiber sources, including paper and paper products (e.g.,
polycoated paper and Kraft paper), and lignocellulosic fiber
sources, including wood, and wood-related materials, e.g., particle
board. Other suitable fiber sources include natural fiber sources,
e.g., grasses, rice hulls, bagasse, cotton, jute, hemp, flax,
bamboo, sisal, abaca, straw, corn cobs, rice hulls, coconut hair;
fiber sources high in .alpha.-cellulose content, e.g., cotton; and
synthetic fiber sources, e.g., extruded yarn (oriented yarn or
un-oriented yarn). Lignocellulosic feedstock can be plant biomass
such as, but not limited to, non-woody plant biomass, cultivated
crops, such as, but not limited to, grasses, for example, but not
limited to, C4 grasses, such as switchgrass, cord grass, rye grass,
miscanthus, reed canary grass, or a combination thereof, or sugar
processing residues such as bagasse, or beet pulp, agricultural
residues, for example, soybean stover, corn stover, rice straw,
rice hulls, barley straw, corn cobs, wheat straw, canola straw,
rice straw, oat straw, oat hulls, corn fiber, recycled wood pulp
fiber, sawdust, hardwood, for example aspen wood and sawdust,
softwood, or a combination thereof. It can also include microbial
biomass such as those derived from naturally occurring or
genetically modified unicellular organisms and/or multicellular
organisms, e.g., organisms from the ocean, lakes, bodies of water,
e.g., salt water or fresh water, or on land, and that contains a
source of carbohydrate (e.g., cellulose). Microbial biomass can
include, but is not limited to, for example protists (e.g., animal
(e.g., protozoa such as flagellates, amoeboid, ciliates, and
sporozoa) and plant (e.g., algae such alveolates,
chlorarachniophytes, cryptomonads, euglenids, glaucophytes,
haptophytes, red algae, stramenopiles, and viridaeplantae)),
seaweed, plankton (e.g., macroplankton, mesoplankton,
microplankton, nanoplankton, picoplankton, and femptoplankton),
phytoplankton, bacteria (e.g., gram positive bacteria, gram
negative bacteria, and extremophiles), yeast and/or mixtures of
these. In some instances, microbial biomass can be obtained from
natural sources, e.g., the ocean, lakes, bodies of water, e.g.,
salt water or fresh water, or on land. Alternatively, or in
addition, microbial biomass can be obtained from culture systems,
e.g., large scale dry and wet culture systems. In some embodiments,
the animal biomass can be used to generate ethanol of unique
composition and/or properties. Animal biomass includes any organic
waste material such as animal-derived waste material or excrement
or human waste material or excrement (e.g., manure and sewage). In
some embodiments, feedstocks are obtained from plants that have
been modified with respect to a wild type variety, e.g., by genetic
modification or other types of modification, can be processed to
produce useful intermediates and products such as those described
herein. Such modifications may be for example, by any of the
methods described in any patent or patent application referenced
herein. As another example, plants may be modified through the
iterative steps of selection and breeding to obtain desired traits
in a plant. Furthermore, the plants can have had genetic material
removed, modified, silenced and/or added with respect to the wild
type variety. For example, genetically modified plants can be
produced by recombinant DNA methods, where genetic modifications
include introducing or modifying specific genes from parental
varieties, or, for example, by using transgenic breeding wherein a
specific gene or genes are introduced to a plant from a different
species of plant and/or bacteria. Another way to create genetic
variation is through mutation breeding wherein new alleles are
artificially created from endogeneous genes or by exogenous
genes.
[0292] In some embodiments, the ethanol of unique compositions
and/or properties derived from various types of biomass can be
mixed with each other in various combinations. For example, in some
embodiments, the ethanol compositions described in FIGS. 10 and
12A, B to 16A, B can be mixed with each other in various
combinations. In some embodiments, the ethanol of unique
composition and/or properties derived from various types of biomass
can be mixed with each other and with ethanol obtained from other
sources. In some embodiments, the ethanol of unique composition
and/or properties derived from various types of biomass can be
mixed with each other and/or with hydrocarbons, aromatics or other
sources of energy. Since the ethanol feedstock has unique
composition and/or properties, the resulting mixture can also have
unique composition and/or properties. In some embodiments, the
mixture contains lignocellulosic ethanol containing about 0.02%
acetone, about 0.11 to about 2.5% methanol, about 0.18% n-propanol,
about 0.12% of 2-methyl propanol, about 0.01% n-butanol, about
0.53% 2-methyl butanol and about 8.5% isopropyl alcohol.
[0293] In some embodiments, the ethanol or ethanol combination
described above can be used as fuel, fuel blends or additives or as
building blocks for other value-added products. Since the ethanol
feedstock has unique composition and/or properties, the resulting
fuel, fuel blends, additives or intermediates can also have unique
composition and/or properties. For example, when used as fuel, the
fuel may have an octane number of about 1 to about 10, about 10 to
about 20, about 20 to about 30, about 30 to about 40, about 40 to
about 50, about 50 to about 60, about 60 to about 70, about 70 to
about 80, about 90 to about 100, about 100 to about 110, about 110
to about 120, about 120 to about 130, about 130 to about 140, about
140 to about 150, about 150 to about 160, about 160 to about 170,
about 170 to about 180, about 180 to about 190, about 190 to about
200, or in a range bounded by any numerical value stated herein
above. The resulting fuel may also have other unique properties
such as density, viscosity, freezing point, volatility and flash
point.
[0294] In some embodiments, the ethanol of unique composition
and/or properties derived from various types of biomass can be used
as feedstocks for making hydrocarbon mixtures of unique composition
by using the processes described herein. Details of such processes,
including catalytic processes have been described elsewhere in this
application. For example, the ethanol compositions described in
FIGS. 10 and 12A, B to 16A, B can be used as feedstocks for making
hydrocarbon mixtures of unique composition by using the processes
described herein. In some embodiments, the hydrocarbons derived
from one type of biomass may have a different composition than that
derived from another type of biomass. For example, the hydrocarbon
composition derived from lignocellulosic ethanol (eg., ethanol
shown in FIGS. 10 and 12A, B) may have a different composition from
those obtained from cane-derived ethanol (eg., ethanol shown in
FIGS. 13A, B). In some embodiments, the hydrocarbon composition
derived from lignocellulosic ethanol may have a different
composition than that derived from other biomass sources, such as
cane, corn, wheat, and grape. The hydrocarbon composition derived
from one type of ethanol can be different from that derived from
another type of ethanol (such as ethanol derived from another type
or source of biomass, or a non-biomass material). For example, the
hydrocarbon composition may have unique ratio of unsaturated
hydrocarbons to saturated hydrocarbons, aromatic to non-aromatic
hydrocarbons, odd-numbered to even-numbered hydrocarbons, and low
molecular weight to high molecular weight hydrocarbons.
[0295] In some embodiments, the hydrocarbons obtained from the
ethanol of unique composition may exhibit unique properties. For
example, the resulting hydrocarbons may have an octane number of
about 1 to about 10, about 10 to about 20, about 20 to about 30,
about 30 to about 40, about 40 to about 50, about 50 to about 60,
about 60 to about 70, about 70 to about 80, about 90 to about 100,
about 100 to about 110, about 110 to about 120, about 120 to about
130, about 130 to about 140, about 140 to about 150, about 150 to
about 160, about 160 to about 170, about 170 to about 180, about
180 to about 190, about 190 to about 200, or in a range bounded by
any numerical value stated herein above. The resulting hydrocarbon
mixture may also have other unique properties such as density,
viscosity, freezing point, volatility and flash point.
[0296] The hydrocarbon mixtures of unique composition generated by
the processes described herein can be used as fuel or fuel blends,
for example, as components of aviation fuel, jet fuel, gasoline,
diesel, kerosene, LPG, heating oil, rocket fuel, and various other
types of transportation and heating fuel. Examples of energy
products that can be generated from the hydrocarbon compositions
described above include gaseous fuels (eg., biogas, syngas,
hydrogen, methane, etc.), solid fuels (eg., coke, pellets, lignin
etc.), and liquid fuels (eg., ethanol, diesel, jet fuel etc.). They
may be also converted to other value-added products, such as coke,
carbon, additives, waxes, greases, lubricants, and asphalts. The
hydrocarbon mixtures of unique compositions and/or properties can
be mixed with other hydrocarbons, whether produced by the processes
described herein or produced by other methods.
[0297] Similarly, a number of other products such as fatty esters,
aromatics, higher alcohols and oxygenated polyols can be obtained
from the ethanol of unique composition and/or properties described
above. These products can also exhibit unique compositions and/or
properties depending on the type of ethanol used as feedstock in
their preparation. For example, the products derived from
lignocellulosic ethanol (eg., ethanol shown in FIGS. 10 and 12A, B)
may have a different composition and property than those obtained
from cane-derived ethanol (eg., ethanol shown in FIGS. 13A, B). In
some embodiments, the products derived from lignocellulosic ethanol
may have a composition that is different than that derived from
other biomass sources, such as cane, corn, wheat, and grape. The
products derived from one type of ethanol can have a different
composition and property than that derived from another type of
ethanol (such as ethanol derived from another type or source of
biomass, or a non-biomass material).
[0298] The products produced from the unique ethanol compositions
described above can further act as building blocks for a large
number of biochemical products that can be used in the textile
industry (eg., in making carpets, fibers, fabrics etc.), food
industry (eg., in food packaging, preservatives etc.),
transportation industry (eg., in making tires, molded plastics
etc.), housing industry (eg., in making paints, resins, cements,
garbage bags, glue etc.), furnitures, sports industry (eg., in
making athletic gears, balls, roller blades, camera films etc.),
communications industry (eg., in making dyes, fiber coatings),
cosmetic industry (eg., perfumes, deodarants, shampoos, toothpaste
etc.) and health industry (eg., in making medical devices and
pharmaceuticals).
[0299] In one or more embodiments, the fermentation can produce a
carboxylic acid, for example, as described in U.S. application Ser.
No. 13/177,827 filed on Jul. 7, 2011 and U.S. application Ser. No.
13/668,358 filed on Nov. 5, 2012, the entire disclosure of which
are incorporated herein by reference. The carboxylic acid can be,
for example any carboxylic acid with between 1 to 20 carbons and 1
to 5 carboxylic acid (--CO.sub.2H) groups (e.g., 1 to 10 carbons
and 1 to 4 carboxylic acid groups, 1 to 5 carbons and 1 to 3
carboxylic acid groups). For example some carboxylic acids that can
be utilized in the methods described herein are acetic acid,
propionic acid, tartaric acid, malonic acid, succinic acid,
glutaric acid, adipic acid, benzoic acid, phthalic acid, maleic
acid, gluconic acid, traumatic acid, muconic acid, butyric acid
(e.g., n-butyric acid, isobutyric acid), valeric acid, caproic
acid, lauric acid, palmitic acid, stearic acid and arachidic acid.
Some suitable microorganisms to produce butyrate can include C.
saccharobutylacetonicum, C. saccharoperbutylacetonicum, C.
saccharobutylicum, C. puniceum, C. beijernckii, C. acetobutylicum,
C. acetobutylicum, C. roseum, C. aurantibutyricum, C. felsineum and
C. tyrobutyricum.
[0300] FIG. 2 shows an example of a reaction scheme for converting
a sugar to an alcohol, specifically butanol. In a first step, for
example, xylose is fermented to n-butyric acid. It should be
understood that the iso-butyric acid may also undergo a similar
reaction scheme. In a second step the butyric acid is contacted
with the quaternary amine functionalized resin Amberlite.TM. 400.
Butyrate becomes associated with the quaternary amine groups and is
extracted from solution in this second step. In a third step the
resin and bound butyrate is contacted with a strong acid, e.g.,
aqueous sulfuric acid, with the effect of protonating the butyrate
and forming free butyric acid. The butyric acid can then be
extracted by ethanol or other alcohol providing butyric acid in an
alcoholic solution. In a fourth step the butyric acid and ethanol
(optionally additional ethanol can be added) is contacted with an
optionally catalyst and heated (e.g., to refluxing temperatures
around 80 to 90.degree. C. at atmospheric pressure) so that an
esterification reaction occurs producing ethyl butyrate.
Alternatively, butyric acid and ethanol can be converted to other
value-added products, including fuel by various processes such as
oligomerization. In a fifth step, the ethyl butyrate is
hydrogenated to butanol and ethanol utilizing hydrogen and a
catalyst (e.g., Re/Al.sub.2O.sub.3). The hydrogenation step can be
carried out in any reactor suited for hydrogenations. The
ethylbutyrate can alternatively be converted to other value-added
products, including fuel by various processes such as
deoxygenation, dehydration, and/or oligomerization. In some
embodiments, n-butanol acts can be converted to other value-added
products such as fuel by various processes such as deoxygenation,
dehydration, and/or oligomerization.
[0301] In other embodiments, sugars with reduced recalcitrance can
also be converted to terpenes. Terpenes can be generated from the
bioconversion of fermentable sugars derived from lignocellulosic
biomass using organisms such as E. coli or S. cerevisiae. There are
at least two known metabolic pathway for the generation of terpenes
and their precursors, isopentenyl pyrophosphate (IPP): the
mevalonic acid (MVA) pathway and the deoxyxylulose-phosphate (DXP)
pathway.
Isolating the Intermediate Building Block from Fermentation
Bath:
Distillation
[0302] After fermentation, the resulting fluids can be purified
using any useful method. For example, some useful methods are
distillation, adsorption, liquid-liquid extraction, perstraction,
reverse osmosis, pervaporation and gas stripping (see, e.g., J.
Ind. Microbiol. Biotechnol. (2009) 36:1127-1138).
[0303] After fermentation, the resulting fluids can be distilled
using, for example, a "beer column" to separate ethanol and other
alcohols from the majority of water and residual solids. The vapor
exiting the beer column can be, e.g., 35% by weight ethanol and can
be fed to a rectification column. A mixture of nearly azeotropic
(92.5%) ethanol and water from the rectification column can be
purified to pure (99.5%) ethanol using vapor-phase molecular
sieves. The beer column bottoms can be sent to the first effect of
a three-effect evaporator. The rectification column reflux
condenser can provide heat for this first effect. After the first
effect, solids can be separated using a centrifuge and dried in a
rotary dryer. A portion (25%) of the centrifuge effluent can be
recycled to fermentation and the rest sent to the second and third
evaporator effects. Most of the evaporator condensate can be
returned to the process as fairly clean condensate with a small
portion split off to waste water treatment to prevent build-up of
low-boiling compounds.
[0304] In other embodiments, carboxylic acid, e.g., butyric acid,
and other fermentation products can be removed/purified by adding
base to the fermentation solution, adding acid to the fermented
solution, extraction, filtration, centrifugation, distillation,
cross flow filtration, membrane filtration, pertraction,
electrodialysis, adsorption and/or bonding to a resin or other
solid, and combinations of these methods. Optionally, after
purification, if the product is wet, the product can be dried, for
example by contacting the product with molecular sieves or other
drying agents (e.g., sodium sulfate, magnesium sulfate). An
extraction method for organic acids including formation of an alkyl
amine adduct in an aqueous solution that can be subsequently
extracted from the aqueous phase is described in U.S. application
Ser. No. 12/935,075 filed Mar. 27, 2009, the entire disclosure of
which is incorporated herein by reference. In one preferred
embodiment, organic acids (e.g., butyric acid) can be extracted by
adsorption/adduct formation/bonding to on a solid support, for
example a resin, solid and/or polymer support.
[0305] In some embodiments the fermented product can be extracted
directly from the fermentation solution or from a solution that has
been distilled. The extracting solvent can be, for example, an
alcohol, an ether, an oil (e.g., castor oil, coconut oil, palm
oil). For example, for the extraction of carboxylic acid (e.g.,
butyric acid), some particularly useful alcohols are fatty
alcohols, for example, having between 6 and 20 carbons and 1 to 5
alcoholic functional groups (e.g., n-hexanol, n-octanol, n-decanol,
n-dodecanol, lauryl alcohol, myristyl alcohol, cetyl alcohol,
stearyl alcohol, oleyl alcohol, linoleyl alcohol, isomers of these
and combinations of these). The acid can be protonated by treating
the solution containing the acid with a mineral acid to adjust the
pH to about pH 3 (e.g., between about pH 2 and 4) prior to
extraction.
[0306] The acid can be esterified as discussed herein to the ester.
The alcohols listed herein can be also utilized to esterify the
fermentation derived acid. The esterification can be done in the
extraction solution. For example, an alcohol can be added to the
extracting solvent. If the extracting solvent is an alcohol, then
the alcohol can be directly utilized for esterification with or
without concentration or dilution of the alcohol. For example,
butyric acid derived from the fermentation of a biomass can be
protonated by the addition of sulfuric acid to the fermented
solution. The butyric acid can be subsequently distilled away from
the acidified solution. The distillate can then be extracted in an
alcohol (e.g., n-octanol). An acid catalyst can be added to the
extracted acid and alcohol and the solution heated to produce an
ester. Alternatively, fermented solution can be acidified and then
directly extracted with an alcohol (e.g., octanol). The mixture can
then be esterified.
[0307] In some embodiments the resins utilized to adsorb organic
acids (e.g., butyric acid) can be polymers with ion exchange
properties, for example having quaternary amine functional groups
that can ion exchange with the acidic proton of the acid. For
example, Amberlite.TM. IRA 410, Amberlite.TM. IRA-67, Amberlite.TM.
96, Amberlite.TM. XAD-1180M, Amberlite.TM. XAD-2, Amberlite.TM. 400
and Amberlite.TM. IRN150. A solution containing the organic acid
can be contacted with the ion exchange resin by passing the
solution through a packed column (e.g., glass, metal, plastic) of
the resin. Optionally, the solution containing the organic acid can
be combined with the resin in a vessel (e.g., in a batch mode) and
agitated (e.g., shaken, stirred) for several minutes to several
hours (e.g., 1 min to 24 hours, 1 min to 12 hours, 1 min to 8
hours, 1 min to 4 hours, 1 min to 1 hour, 1 hour to 4 hours, 1 hour
to 12 hours). In batch mode the organic acid depleted solution can
be decanted or filtered from the resin after a sufficient time to
adsorb/bond at least some of the organic acid. The amount of
butyric acid in the batch separation or column separation methods
can be monitored by any useful method, for example, head space
analysis, titrations and HPLC.
[0308] A resin for adsorbing an organic acid can be contacted with
the fermenting solution while the fermentation is still processing
or after the fermentation is complete. For example, the active
fermentation media can be pumped through a column of the resin or
the resin can be added to the fermentation broth.
[0309] The organic acid can, for example, be removed from the resin
by contacting the resin and bound organic acid with an acid
solution. For example, the acid solution can include a mineral acid
(e.g., hydrochloric, sulfuric, phosphoric, nitric) or the acid can
be an organic acid (acetic acid, trifluoroacetic acid). It is
generally preferable to use an acid with a low pKa, e.g., about
lower than the pKa of butyric acid e.g., a pKa of less than about
4, less than about 3, less than about 2. The pH of the solution
after acidification is optimally between about 1 and 6 (e.g.,
between about 2 and 5, between about 2 and 4). It can be
advantageous to utilize a solvent with or without water to aid in
extracting the organic acid or organic acid salt from the resin.
For example, the solvent can be an alcohol (e.g., methanol,
ethanol, propanol, butanol or the fatty acid alcohols previously
described), an ether (e.g., diethyl ether, tetrahydrofuran, methyl
tert-butyl ether, di-isopropyl ether), acetonitrile, acetone, butyl
acetate, dimethylformamide, ethyl acetate and combinations of
these. These can be combined in any percentage with water and each
other. A preferred method of removing adsorbed organic acid from a
resin packed column is elution with acidified alcohol (e.g. ethanol
and/or methanol with and added acid) or an acidified alcohol/water
solution (e.g., ethanol/water, methanol/water with and added acid).
Resins can be recycled after removal of the acid, for example by
flushing with excess of the acidified solution followed by flushing
with water, optionally deionized water.
[0310] The acidified eluent/extracting solution from the resin
processing containing the carboxylic acid can be neutralized by
addition of a base. This can produce the salt of the carboxylic
acid. The salts of the carboxylic acid can be evaporated to dryness
and then oven dried (e.g. at 80 to 100.degree. C.). The salts can
be subsequently utilized in esterification reactions, with
optionally re-acidification prior to the reaction.
[0311] In an alternative to acidification to remove the organic
acid from the resin, the acidic proton of the organic acid can be
removed by ion exchange with a cation to form the salt of an
organic acid. Some useful exchanging ions include, for example,
quaternary ammonium ions, alkali metal ions and alkali earth metal
ions, transition metal ion and combinations of these. The salt of
the carboxylic acid thus produced can be further processed as
previously discussed.
Conversion of Building Blocks from Processed Biomass to Fuel
[0312] Biomass feedstocks can be converted into intermediate
building blocks through gasification, into alcohols through
biochemical or thermochemical processes, into sugars through
biochemical processes, and into bio-oil through pyrolysis
processes. Syngas, alcohols, sugars, and bio-oils can be further
upgraded to biofuel or components of biofuel blendstock via a
variety of synthesis, fermentative, or catalytic processes.
Catalytic Processes Used in the Conversion of Building Blocks to
Fuel
[0313] A large variety of building blocks, such as alcohols formed
from fermentation process can be used in making components of fuel
blendstock. Exemplary alcohols include methanol, ethanol,
n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, as
well as longer chained alcohols, R C5-C20. Longer chained alcohols
may be particularly attractive, since the larger R group (relative
to OH) can provide a better mass loss on conversion to hydrocarbon.
Other biofuel products such as fatty esters, aromatics and
oxygenated polyols can also be obtained by the stepwise methods
described herein.
[0314] In some embodiments, building blocks produced by the
invention can be converted to alkanes and/or other components of a
biofuel using one or more steps in which multiple chemical
conversions can occur simultaneously. Catalysts can be used to, for
example, promote a number of reactions simultaneously. In one or
more embodiments, catalysts are provided that can e.g.
simultaneously reduce hydrogen content (e.g., dehydrogenation) and
reduce oxygen content (e.g., dehydration). In one embodiment, a
tin-doped Pt/Al.sub.2O.sub.3 catalyst generated by
solvent-impregnation process is used to convert biomass-derived
building blocks to fuel constituents. In other embodiments, the
building blocks can be subjected to a process that simultaneously
reduce hydrogen content, and reduce oxygen content, and increases
molecular weight. The ability to effect multiple changes on the
building blocks in a single reactor can make available a more
complex biocomposition. The ability to effect multiple changes on
the building blocks in a single reactor can also provide complex
mixtures that more closely parallel fuels currently being used in
the transportation industry. Additional advantages also a
simplification of the complexity and cost of the conversion
process. By way of example, an alcohol building block can be
treated with a catalyst that is capable of promoting a number of
reactions so that the input building blocks do not need to pass
through multiple catalyst beds.
Conversion Processes for Alcohols to Fuel
[0315] In some embodiments, alcohols produced from biomass can be
converted to alkanes and/or other components of a fuel through one
or more steps. For example, alcohols can be converted alkenes by
dehydration, and the dehydrated alkene can be oligomerized into
higher olefins. The higher olefins may be subsequently hydrogenated
to produce alkanes. For example, FIG. 3A is a schematic block
diagram illustrating the conversion of alcohol derived from
processed biomass to fuel blends and other value-added products
through dehydration and hydrogenation. In step 301, alcohols are
dehydrated (preferably catalytically) to alkenes. The alkenes
obtained from the dehydration of alcohols can then be oligomerized
in step 303. Alternatively, the alkenes may be isomerized to
convert internal alkenes to terminal alkenes in step 302, followed
by alkene metathesis in step 305. The aim of both the
oligomerization and the metathesis step is to produce higher
olefins. Any lower olefins that remain in the mixture are separated
from the higher olefins and fed back into the loop for further
oligomerization and/or metathesis. In step 306, the higher olefins
are hydrogenated (preferably catalytically) to produce a mixture of
hydrocarbons, which are then separated by distillation and/or other
separation methods in step 307 to form components of various fuel
blends or other value-added products. FIG. 3B is a schematic block
diagram illustrating the conversion of oxygenates derived from
biomass to fuel blends and other value-added products through a
reforming process in the presence of reforming catalyst. In step
3002, oxygenates derived from biomass is subjected to catalytic
reforming. Depending upon the catalysts and reaction conditions,
hydrocarbons are formed through alkene intermediates or through
non-alkene intermediates. In some embodiments, a non-reducing
atmosphere may facilitate the production of alkenes. In other
embodiments, such as under reducing atmosphere, aromatics and
hydrocarbons (cyclic and acyclic) can be predominantly produced. In
step 3004, the hydrocarbon mixture is separated into components
suitable for use in various fuel blendstocks and other value-added
products.
[0316] In some embodiments, the dehydration of alcohols to alkenes
is accomplished catalytically. Dehydration catalysts may include,
for example, alumina, transition metal oxides (such as nickel
oxide, bismuth oxide, titanium oxide, rhodium chloride),
silicoaluminophosphates (SAPO), zeolite catalysts, and acidic
catalysts (such as sulfuric acid, polyphosphoric acid
heteropolyacid catalysts). For example, zeolites of different types
such as ZSM-5 zeolites, X-type zeolites, Y-type zeolites, including
those of various ionic compositions and substitutions and pore
sizes can be used to catalytically dehydrate alcohols. In some
embodiments, dehydration of alcohols to alkenes can be done by
using biocatalysts such as enzymes. The dehydration step may use
homogeneous and/or heterogeneous catalysts. Exemplary dehydration
catalysts include alumina/transition metal oxides, slicoaluminum
phosphates (SAPO), H-ZSM-5 zeolite e.g., (0.5% La-2% P H-ZSM-5
catalyst), heteropolyacid catalyst. Ethanol and n-butanol are
preferred alcohols. In one embodiment, N-butanol can be dehydrated
to 1-butene using, for example, at 380.degree. C. and 2.1 bar.
Ethanol can be dehydrated using, for example, 0.1-5% Pt/transition
metal dopants, such as W or Mo or TiO.sub.2.
[0317] In some embodiments, the olefins obtained from the
dehydration of alcohols are further subjected to oligomerization.
Oligomerization can be used, for example, to convert ethylene and
other smaller olefins into linear .alpha.-olefins. Oligomers can
grow by chain growth through olefinic bond, which usually provides
products with an even number of carbons. Depending on the catalyst
and reaction conditions, oligomerization reactions can form dimers,
trimers, and tetramers.
[0318] The oligomerization may be further achieved catalytically.
Various catalysts such as Ziegler Natta-type catalyst, chromium
diphosphine catalysts, transition metal catalysts (such as nickel
oxide, titanium oxide, bismuth oxide, rhodium chloride), zeolites,
acidic catalysts (such as sulfuric acid, polyphosphoric acid
heteropolyacid catalysts), and Amberlyst-35 catalyst may be used to
catalyze the oligomerization of olefins. The catalysts may be
homogeneous and/or heterogeneous.
[0319] In some embodiments, the higher olefins obtained by
oligomerization are further subjected to dimerization. The
dimerization may be further achieved catalytically. Various
catalysts such Nafion catalyst, Ziegler Natta-type catalysts,
transition metal catalysts (such as nickel oxide, bismuth oxide,
Rhodium chloride), zeolites, alumina, silicoaluminophosphates
(SAPO), and acidic catalysts (such as sulfuric acid, polyphosphoric
acid heteropolyacid catalysts) may be used for dimerization. The
catalysts may be homogeneous and/or heterogeneous.
[0320] Examples of industrially important linear alpha-olefins
include 1-butene, 1-hexene, 1-octene, 1-decene, 1-dodecene,
1-tetradecene, 1-hexadecene, 1-octadecene and higher blends of
C.sub.20-C.sub.24, C.sub.24-C.sub.30, and C.sub.20-C.sub.30 ranges.
For example, in some embodiments, oligomerization of 1-butene with
group 4 transition-metal catalysts in the presence of
methylaluminoxane (Cp2ZrC22/MAO) can lead to higher weight C8-C32;
2-butene does not react and can be recycled. In another embodiment,
oligomerization of ethylene using Ziegler-Natta catalyst at
90-110.degree. C. and 89 bar pressure can give 96-97% yield of
C4-C20 carbons
[0321] In other embodiments, the molecular weight of olefins can be
increased by alkene metathesis through the formation of
metal-carbenes (M=CH.sub.2) or metal-alkylidene complexes. This
reaction facilitates the reaction of alkenes or alkynes, typically
containing terminal double or triple bonds to form different or
higher olefins. Different types of metathesis reactions can be used
to form higher olefins, including cross-metathesis, ring closing
metathesis, acyclic diene metathesis polymerization, ring opening
metathesis polymerization, enyne metathesis, and ring-opening
cross-metathesis. It can be used to generate both homodimers and
heterodimers, polymeric compounds, cyclic and linear olefins.
[0322] In some embodiments, alkene metathesis is preceded by an
isomerization process that can convert internal alkenes to terminal
alkenes. The isomerization can be accomplished in a liquid medium
in the presence of catalysts, such as alkaline alumina catalysts.
Alternatively, internal alkenes can be reacted with excess ethylene
in the presence of catalysts such as rhenium (IV) oxide supported
on alumina in a process called ethanolysis, which causes the
internal double bond to break up to form a mixture of
.alpha.-olefins with odd and even carbon chain-length of the
desired molecular weight.
[0323] The alkene metathesis process can be carried out in the
presence of catalysts such as Schrock catalysts (such as
CpTa(.dbd.CH-t-Bu)Cl.sub.2, and other Mo(IV)-based, and W(IV)-based
catalysts), Grubbs catalysts (Ru-based catalysts containing
phosphine ligands), Hoveyda-Grubbs catalyst (Ru-based catalysts
containing isopropoxystyrene ligands), Osmium-based catalyst,
tungsten-halide-based catalysts, lithium aluminum tetraheptyl and
titanium tetrachloride, tungsten(VI) oxytetrachloride and
tetrabutyltin, cis-bis(triphenylphosphine)dichloroplatinum(II), and
several other transition metal catalysts.
[0324] The resulting products from oligomerization and/or alkene
metathesis can have a broad carbon number distribution and the
pressure, temperature, catalytic conditions can be varied to
achieve the desired carbon distribution. For example, the
oligomerized products may have about 5% C.sub.4, about 10% C.sub.4,
about 20% C.sub.4, about 30% C.sub.4, about 40% C.sub.4, about 50%
C.sub.4, about 60% C.sub.4, about 70% C.sub.4, about 80% C.sub.4,
about 90% C.sub.4. The oligomerized products may have about 5%
C.sub.6-10, about 10% C.sub.6-10, about 20% C.sub.6-10, about 30%
C.sub.6-10, about 40% C.sub.6-10, about 50% C.sub.6-10, about 60%
C.sub.6-10, about 70% C.sub.6-10, about 80% C.sub.6-10, about 90%
C.sub.6-10. The oligomerized products may have about 5%
C.sub.12-14, about 10% C.sub.12-14, about 20% C.sub.12-14, about
30% C.sub.12-14, about 40% C.sub.12-14, about 50% C.sub.12-14,
about 60% C.sub.12-14, about 70% C.sub.12-14, about 80%
C.sub.12-14, and about 90% C.sub.12-14. The oligomerized products
may have about 5% C.sub.16-18, about 10% C.sub.16-18, about 20%
C.sub.16-18, about 30% C.sub.16-18, about 40% C.sub.16-18, about
50% C.sub.16-18, about 60% C.sub.16-18, about 70% C.sub.16-18,
about 80% C.sub.16-18, and about 90% C.sub.16-18. The oligomerized
products may have about 5% C.sub.20 about 10% C.sub.20, about 20%
C.sub.20, about 30% C.sub.20, about 40% C.sub.20, about 50%
C.sub.20, about 60% C.sub.20, about 70% C.sub.20, about 80%
C.sub.20, and about 90% C.sub.20. The oligomerized products may
have about 5% C.sub.20 about 10% C.sub.20+, about 20% C.sub.20+,
about 30% C.sub.20+, about 40% C.sub.20+, about 50% C.sub.20+,
about 60% C.sub.20+, about 70% C.sub.20+, about 80% C.sub.20+, and
about 90% C.sub.20+.
[0325] The olefins produced from the process described in this
invention can be separated by distillation. Lighter olefins (such
as C.sub.4-C.sub.8) may be further subjected to dimerization,
oligomerization and/or alkene metathesis. The higher olefins are
distilled into fractions suitable for making various types of fuels
such as gasoline, diesel, aviation fuel, jet fuel, kerosene or
other value-added products. The higher olefins can be hydrotreated
to decrease the carbon-to-hydrogen balance either before or after
the separation of the olefins to fuel-appropriate fractions.
Hydrotreating can be used to either hydrogenate unsaturated bonds,
or to remove oxygen. For example, the higher olefins can be
hydrogenated to corresponding hydrocarbons. Alternatively, the
olefins can be dehydrogenation to produce aldehydes and/or ketones,
which can then be deoxygenated to produce hydrocarbons.
[0326] Hydrogenation of higher olefins to the desired hydrocarbons
may be accomplished by treating the olefins with hydrogen in the
presence of catalysts. Catalysts are utilized during the
hydrogenolysis. The catalysts may be homogeneous and/or
heterogeneous. Catalysts can include the metals Pd, Pt, Os, Ru, Rb,
Re, Ir, Rh, Ni, Co, Mo, W, Cu, Zn, Cr, oxides of these and
combinations of these. Examples of hydrogenation catalysts include,
but are not limited to, palladium or platinum on activated carbon
or Calcium Carbonate, PtO.sub.2, Raney/Ni, RhCl (PPh.sub.3).sub.3,
Ru catalysts, Lindlar's catalyst, and various transition metal
catalysts. In some cases, promoter or moderator species are
added/combined including Cr, Mn, Pb, Zn, Cd, Ag, Ba, Ca, Mg, Sn,
Ni, Co, U, As and Ge oxides and combinations of these. One or more
catalyst and one or more promoter can be combined in any
concentration and ratio. The promoters increase the performance of
the catalyst, for example, by increasing the conversion and
selectivity.
[0327] In some embodiments, the alcohols may be subjected to
dehydrogenation to produce aldehydes and/or ketones. These ketones
and aldehydes can then be deoxygenated to produce hydrocarbons. In
some embodiments, dehydrogenation of alcohols can be achieved
catalytically. For example, catalysts such as
Pd/C--K.sub.3PO.sub.4, copper-chromium oxide catalyst,
RuCl.sub.2(PPh.sub.3).sub.3, (.eta..sup.5-Cp)RuCl(PPh.sub.3).sub.2,
[(.eta..sup.5-Cp)IrCl.sub.2].sub.2, Rh-catalysts such as Noyori
catalyst, Grutzmacher catalyst, Ru-catalysts such as Shvo catalyst,
Stradiotto catalyst, Milstein catalyst, 0.1-5% Pt/transition metal
dopants, such as W or Mo on active carbon or alumina, and several
other transition metal catalysts may be used to dehydrogenate
alcohols to aldehydes or ketones. Next, the aldehydes and ketones
generated in the previous step can be deoxygenated by using
catalysts. Removal of oxygen may be accomplished by decarboxylation
(CO.sub.2) and/or dehydration (H.sub.2O) and can be done in the
presence/absence of hydrogen. Several deoxygenation catalysts,
homogeneous or non-homegeneous, may be used for this step. For
example, transition metal catalysts such as CoMo-based catalysts,
sulfide CoMo/Alumina, NiMo/Alumina, Pd-based catalysts (such as
palladium-supported activated carbon), Pt-based catalysts, mixed
metal oxides (such as MgO+MgAl.sub.2O.sub.4), and precious metal
catalysts can be used. FIG. 4 provides a schematic block diagram
illustrating an example of the process that can be used to convert
alcohol derived from processed biomass to fuel blends and other
value-added products. The first step, 401, involves the
dehydrogenation of alcohols (preferably catalytically) to aldehydes
and/or ketones. The aldehydes and/or ketones are then subjected to
deoxygenation (preferably catalytically) in step 402 to produce a
mixture of hydrocarbons. The mixture of hydrocarbons are then
separated in step 403 by using various methods such as distillation
to components suitable for use in various fuel blends and other
value-added products.
[0328] Suitable dopants that can also be used to improve the
dispersion of the metal catalysts and reduce the formation of coke
include alkali metals (such as Li, Na, and K), transition metals
(such as Ti, Zr, Hf, Nb, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir,
Ni, Pd, Pt, Cu, Ag, Au), mixtures of transition metals (such as
Ti/Hf, Ti/Zr, Zr/Cr), organometallic complexes (such as Cp.sub.2 V,
(butadiene).sub.3 Mo, Bis-(arene) complexes of zero-valent Ti, Zr
or Hf), promoter metals (such as germanium, indium, gallium,
thallium), rare earth elements (such as La), halogens (such as
fluorine, chlorine, bromine and iodine), hydrogen, hydrogen
sulfide, tin, and sulfur.
Ethanol
[0329] In one embodiment, ethanol obtained from biomass is
dehydrated to ethylene over 0.5% La-2% H-ZSM-5 catalyst. Higher
yields and selectivity can be achieved by optimizing the
temperature and time of dehydration. Commercial processes for
making olefins may use both homogeneous and heterogeneous
catalysts. The dehydrated ethylene can then be turned into linear
olefins via a catalytic oligomerization process. Catalysts such as
a Ziegler Natta-type catalyst, chromium diphosphine catalyst and
zeolites may be used for the oligomerization process. For example,
a temperature of 90-110.degree. C. and a pressure of 89 bar over a
Ziegler Natta-type catalyst may produce 96-97% yield of linear
.alpha.-olefins with a carbon range of C.sub.4-C.sub.20. The
oligomerization process may yield olefins of broad carbon number
distribution, such a 5% C.sub.4, 50% C.sub.6-C.sub.10, 30% C.sub.12
and C.sub.14, 12% C.sub.16 and C.sub.18, 3% C.sub.20 and C.sub.20+,
at 200.degree. C. and 250 bar. The resulting olefins are distilled
to gasoline-, diesel-, jet fuel-, aviation fuel, kerosene-range
fuels and light olefins. Light olefins (C4-C8) separated by
distillation are recycled back to the oligomerization step. Higher
olefins, such as jet fuel-range products are subjected to
hydrogenation, at temperatures of 370.degree. C. and weight hourly
space velocity (WHSV) of 3 h.sup.-1, by feeding hydrogen over 5% by
weight of Pd or Pt-based catalyst on activated carbon.
Alternatively, the higher olefins can be subjected to stepwise
catalytic dehydrogenation and deoxygenation to produce higher
alkanes. The higher alkanes can be separated and use as components
of different fuels and value-added products.
N-Butanol
[0330] In one embodiment, n-butanol derived from biomass can be
dehydrated to 1-butene at 380.degree. C. and 2.1 bar over the
.gamma.-alumina catalyst. In one embodiment, the dehydration
produces 1-butene with high yield and selectivity. A by-product
such as 2-butene can also be produced as a result of isomerization
from 1-butene. The 2-butene, containing cis- and trans-2-butenes,
may be considered as unreacted olefins and separated by temperature
controlled distillation. The 1-butene thus produced may be
subjected to the oligomerization process to produce olefins ranging
from C.sub.8 to C.sub.32. In some embodiments, the conversion to
higher olefin is accomplished with a high yield by varying factors
such temperature, time, flow-rate and catalysts. In some
embodiments, the product distributions of the mixed olefins may be
about 26% C.sub.8, about 25% C.sub.12, about 18% C.sub.16, about
12% C.sub.20, about 8% C.sub.24, about 5% C.sub.28 and about 4%
C.sub.32. In one embodiment, the reaction can be operated at
ambient temperature with stirring for 16 h over the Group 4
transition-metal catalysts in the presence of methylaluminoxane
(eg., Cp.sub.2ZrCl.sub.2/MAO). The C.sub.8 olefin,
2-ethyl-1-hexene, can be distillated and sent to the dimerization
reactor. The dimerization of the C.sub.8 olefin can be operated at
116.degree. C. for 2 h over Nafion catalyst. As a result of the
dimerization, the C.sub.8 olefin may be converted with high yield
to C.sub.16H.sub.32. The products from the oligomerization and
dimerization steps, ranging from C.sub.12 to C.sub.32, can be
further subjected to hydrogenation over 0.08 wt % PtO.sub.2
catalyst. The resulting C.sub.12-C.sub.16 paraffins can be blended
with jet fuel components, and the C.sub.20-C.sub.32 alkanes are
separated and sold as lubricants.
[0331] In some embodiments, n-butanol derived from biomass can be
dehydrogenated over a catalyst such as Pd/C--K.sub.3PO.sub.4
catalyst, producing C.sub.5-C.sub.11 ketones. These ketones can be
catalytically deoxygenated to produce normal paraffins, and the
components of jet, gasoline, and diesel fuels. Examples of
dehydrogenation and deoxygenation catalysts have been previously
described.
Isobutanol
[0332] In one embodiment, iso-butanol produced from a process such
as Escherichia coli fermentation is dehydrated to a mixture of
isobutene, n-butene (1-butene), and 2-butene (cis-2-butene and
trans-2-butene). Catalysts such as ZSM-5 zeolites, Y-type zeolites,
and Amberlyst acidic resins can be used to catalyze a dehydration
reaction, and different catalysts affect the selectivity of
isobutene and the overall linear butenes. In one embodiment, a high
selectivity and yield of isobutene may be obtained by using ZSM-5
catalyst at 2 h.sup.-1 WHSV. In addition, isobutanol can be
converted into isobutylene in high yield and selectivity through a
dehydration process operated at 310.degree. C. over .gamma.-Alumina
catalyst. In another embodiment, the isobutene can be converted to
oligomers, trimers, and tetramers at 100.degree. C. using an
Amberlyst-35 catalyst at a WHSV of 2 h.sup.-1. In some embodiments,
the isobutene oligomerization produces about 20%, about 70%, and
about 10% for C.sub.8, C.sub.12 and C.sub.16 olefins, respectively.
To increase the yield of higher olefins, the C.sub.8 olefins can be
distilled and sent to one additional dimerization process,
operating at for example, 116.degree. C. over a Nafion catalyst.
Alternatively, C.sub.8 olefins can be either converted into
C.sub.16H.sub.32 through dimerization or reacted with butenes to
produce C.sub.12 olefins, leading to the increase of C.sub.12 and
C.sub.16 for the jet-range chemicals. These olefins can then be
hydrogenated or subjected to dehydrogenation followed by
deoxygenation to produce the corresponding alkanes.
Conversion of Polyalcohols (Reduced Sugars) to Fuel
[0333] In some embodiments, the sugars obtained from the processing
of lignocellulosic material such as glucose (C.sub.6) or xylose
(C.sub.5), can be hydrogenated to produce the corresponding reduced
sugars, sorbitol (C.sub.6H.sub.14O.sub.6) or xylitol
(C.sub.5H.sub.12O.sub.5). In some embodiments, the sugar used is
raw sugar, which has not been purified, and is unrefined, or
partially refined. For example, raw sugar can be extracted from
plants such as sugarcane or beet. In addition to sucrose, raw sugar
may also contain about 1% molasses by volume, about 2% molasses by
volume, about 3% molasses by volume, about 4% molasses by volume,
about 5% molasses by volume, about 6% molasses by volume, about 7%
molasses by volume, about 8% molasses by volume, about 9% molasses
by volume, about 10% molasses by volume, about 20% molasses by
volume, about 30% molasses by volume, about 40% molasses by volume,
and about 50% molasses by volume. This hydrogenation step can be
performed by heterogeneous catalysis or homogeneous catalysis, and
sometimes can also combined with the hydrolysis step of the
cellulose. Polyols such as sorbitol and xylitol can then be
converted to hexanes and pentanes respectively by catalytic
dehydration, followed by hydrogenation. There are several ways that
sugars and reduced sugars can be converted to fuel, including
catalytic decarboxylation, dehydration and hydrodeoxygenation.
[0334] In one embodiment, following the pretreatment and
fractionation processes, lignocellulosic biomass is converted and
separated to cellulose, hemi-cellulose, and lignin. Lignin, in this
process, is sent to the combustor to provide process heat. Using
enzymatic or acid hydrolysis, the fractionated cellulose and
hemicellulose can then be turned into sugars with five and six
carbons. The carbohydrates are converted into polyhydric alcohols
via hydrogenation or short-chain oxygenates via hydrogenolysis.
Longer polyols may be further converted to shorter polyols (eg.,
glycerol, ethylene glycol) by catalytic conversion such as by using
nickel-based catalyst in a basic environment.
Aqueous Based Dehydration to Alkenes Followed by Hydrogenation
(APD/H)
[0335] In some embodiments, polyols derived from biomass may be
used to produce the corresponding alkanes by an aqueous phase
dehydration/hydrogenation process (APD/H). In some embodiments, the
process may involve treatment with hydrogen, while in some
embodiments, hydrogen may not be needed. The process may be
catalyzed by a number of catalysts, including bifunctional
catalysts combining a metal phase (eg., platinum) on an acid
support (eg., silica-alumina). The support acidity assists in the
dehydration reactions that eliminate oxygen in the form of
H.sub.2O. A number of acidic support can be used for the catalysts,
including activated carbon, SiO.sub.2--Al.sub.2O.sub.3, TiO.sub.2,
ZrO.sub.2, Zeolites (HZSM-5, H-mordenite and HY), phosphated
zirconia, niobium oxide, phosphated titanium oxide, phosphated
niobium oxide, tungstated zirconia, molybdenum doped zirconia, NaY,
ZnO and MgO. Catalysts such as Raney Copper catalyst, Ru/C
catalyst, Pt/C, Pt/Al.sub.2O.sub.3, Pt/NaY, Ru/C catalyst+acid
resin (Amberlyst) may also be used.
[0336] The resulting alkenes are then saturated to alkanes by
hydrogenation. Methods of hydrogenation, including the various
types of catalysts have been described earlier. Alternatively, the
alkenes can be oligomerized to heavier alkenes, cracked, cyclized
and dehydrogenated to aromatics
[0337] To obtain alkanes from long-chain polyols, the
dehydration/hydrogenation steps must be repeated several times
without undesired C--C bond cleavage. One advantage of the aqueous
dehydration/hydrogenation process is that separation of the
products is supposed to be simplified as the alkanes theoretically
form a hydrophobic phase that separates from an aqueous
environment. Alkanes can then be integrated into the classic
refinery circuit and fractionated into components suitable for use
in fuel blends and as other value-added products.
Aqueous Phase Reforming
[0338] In some embodiments, polyols derived from biomass can be
used to produce hydrogen by a process called aqueous phase
reforming (APR). APR consists of two steps: the first step involves
reforming of the polyol into hydrogen and CO, and the second step
involves transforming the CO to CO.sub.2 and hydrogen by the Water
Gas Shift (WGS) reaction. These two reactions can be catalyzed by
catalysts such as supported metal catalyst (eg., Pt/alumina).
Hydrogen produced from APR can be used to support a hydrotreating
process before the APR step and a hydro-refining processes after
the APR step. In some embodiments the APR process is combined with
the APD/H process described above.
Aldol Condensation on Multi-Functional Solid-Base Catalysts
[0339] In one embodiment, polyols derived from biomass can be
converted to alkanes by direct catalytic condensation over
multifunctional solid-base catalysts. An aldol mechanism can occur
on metallic sites under basic conditions. For example, a polyol
like sorbitol can first be dehydrogenated, probably on a metal
site, to form a ketone group in position 2 or 3; that ketone is
then involved in the retro-aldol reaction mechanism that leads to
the formation of an aldol and an aldehyde. These products are then
deoxygenated and hydrogenated on the metal surface. The products
from this route can then be used, for example, in the jet fuel
blends.
Sugar to Hydrocarbons Via Polyhydroxybutyrate
[0340] Hydrocarbons can also be produced from sugars via a
polyhydroxybutyrate intermediate. In one embodiment, a sugar like
glucose is converted to polyhydroxybutyrate (PHB) by bacterial
fermentation. PHB-producing strains, such as Alcaligene eutrophis,
Ralstonia eutropha, Azotobacter vinelandii, Alcaligenes latus,
Hydrogenophaga pseudoflava, and Pseudomonas pseudoflava can be used
for this process. Genetically modified microorganisms may also be
used for this process. The PHB, thus produced, is then
depolymerized to crotonic acid, which is then decarboxylated to
produce propene. Examples of depolymerization catalysts include
dibutyltin dimethoxide, p-toluenesulfonic acid CaCl.sub.2,
MgCl.sub.2. MgO, and Mg (OH).sub.2. In some embodiments, the
depolymerization and decarboxylation step can be combined in one
step, for example, by heating at 400.degree. C., with or without a
catalyst.
[0341] The propene is then oligomerized to generate hydrocarbons.
Various catalysts such as Ziegler Natta-type catalyst, chromium
diphosphine catalysts, transition metal catalysts (such as nickel
oxide, titanium oxide, bismuth oxide, rhodium chloride), zeolites,
acidic catalysts (such as sulfuric acid, polyphosphoric acid
heteropolyacid catalysts), and Amberlyst-35 catalyst may be used to
catalyze the oligomerization of olefins. The catalysts may be
homogeneous and/or heterogeneous. In some embodiments, the higher
olefins obtained by oligomerization are further subjected to
dimerization. The dimerization may be further achieved
catalytically. Various catalysts such Nafion catalyst, Ziegler
Natta-type catalysts, transition metal catalysts (such as nicker
oxide, bismuth oxide, Rhodium chloride), zeolites, alumina,
silicoaluminophosphates (SAPO), and acidic catalysts (such as
sulfuric acid, polyphosphoric acid heteropolyacid catalysts) may be
used for dimerization. The catalysts may be homogeneous and/or
heterogeneous. Pressure, heat, reaction time and other parameters
can be varied to affect the distribution of products such as cyclic
ketones and phenols.
Sugar to Hydrocarbons Via Furfural-Derived Intermediates
[0342] Sugars like pentose, xylose and glucose can also be used as
building blocks for the production of fuel and additives by
converting them to furfural-derivatives. These sugars can be
dehydrated to furfural, and other derivatives such as
methylfurfural and hydroxymethylfurfural. Catalysts such as
protonated micro-porous zeolites, MgF.sub.2, H.sub.2SO.sub.4,
CrCl.sub.3, ZnCl.sub.2, FeCl.sub.2, CuCl.sub.2, CrCl.sub.2,
C.sub.6H.sub.5--B--C.sub.12 and TiO.sub.2. Acid-catalyzed
condensation of these products with aldehydes and ketones can then
result in products with higher carbon numbers. Alternatively, these
products can undergo cross-coupling reactions with alcohols to give
high molecular weight adducts via a transfer hydrogenation-aldol
condensation pathway. Examples of alcohols include 1-propanol,
1-butanol, 3-methyl-1-butanol, 1-pentanol, 1-hexanol,
1phenylethanol, 1-octanol, 2-propanol. The alcohols used in such
cross-coupling reactions can be obtained by fermentative or
non-fermentative routes from sugar, as well as various by various
other methods described herein. Examples of catalysts that could be
used for such cross-coupling include Fe(BF.sub.4).6H.sub.2O,
Cu(OAc).sub.2, Ni(dppe)Cl.sub.2, in the presence of bases like
K.sub.2CO.sub.3 and
Mg.sub.6Al.sub.2(OH).sub.16CO.sub.3-4H.sub.2O.
[0343] These high carbon products can then be converted to C12 and
C15 hydrocarbons by hydrodeoxygenation. Examples of suitable
catalysts include heterogenous bifunctional platinum on niobium
phosphate (Pt/NbOPO.sub.4), and Pt--SiO.sub.2/Al.sub.2O.sub.3. For
example, hydrodeoxygenation can be undertaken at 300.degree. C.,
100 bar H.sub.2 over Pt--SiO.sub.2/Al.sub.2O.sub.3 catalyst, or at
250.degree. C., 100 psi H.sub.2, in the presence of Pt/NbOPO.sub.4
catalyst. The H.sub.2 used in these reactions can be produced on
site by the various processes described herein.
[0344] As discussed in this application, the hydrocarbon molecules
produced by any of the processes described herein are often in
mixtures, and are separated in a fractionation process to
components specifically tailored towards various fuels such jet,
gasoline, and diesel fuels. Depending upon the carbon content of
the hydrocarbons generated by the already described process they
can be used in different types of fuels. For example, C8-C16
hydrocarbons are suitable for jet fuels, C9-C22 hydrocarbons may be
suitable for diesel, and C4-C12 hydrocarbons may be used for making
gasoline.
[0345] In addition, the processes described herein can be used to
generate additives. In some embodiments, additives are blended with
oil products to modify their properties including modification of
octane number, cetane number, cold properties, lubricity,
viscosity, contaminants, and as antioxidants, stabilizers and
biocides.
[0346] A number of other compounds produced by the above-described
process can further act as building blocks for a large number of
biochemical products that can be used in the textile industry (eg.,
in making carpets, fibers, fabrics etc.), food industry (eg., in
food packaging, preservatives etc.), transportation industry (eg.,
in making tires, molded plastics etc.), housing industry (eg., in
making paints, resins, cements, garbage bags, glue etc.),
furnitures, sports industry (eg., in making athletic gears, balls,
roller blades, camera films etc.), communications industry (eg., in
making dyes, fiber coatings), cosmetic industry (eg., perfumes,
deodarants, shampoos, toothpaste etc.) and health industry (eg., in
making medical devices and pharmaceuticals). For example, furfural
can be used for the production of furfuryl alcohol,
2-methyltetrahydrofuran (MTHF) and other 5-membered
oxygen-containing heterocyclic compounds such as methylfuran,
acetylfuran and furoic acid. Sugar-to-Fuel Pipeline
[0347] Lignocellulosic sugars produced by pretreatment and
enzymatic hydrolysis of biomass feedstocks typically need a certain
level of purification and concentration of biomass before
catalytically upgrading sugar to hydrocarbons, which converts sugar
or its intermediates to a range of hydrocarbon molecules and
hydrogen in an APR and/or APD/H process.
[0348] The hydrosylate slurry of lignocellulosic sugars produced by
reducing fermentation and irradiation is purified through a number
of steps for further downstream processing requirements of the
catalytic upgrading processes. Insoluble solids, resulting from
unreacted or recondensed biomass components are removed by
centrifugation or filtration because they can build up in a fixed
bed reactor system and cause high pressure drop. Proteins and
inorganic compounds in hydrolysates are also problematic for
catalytic processing, as they impact materials of construction,
accumulate in heat exchangers and contribute to catalyst poisoning.
Removal of these contaminants is achieved utilizing technologies,
such as ion exchange methods. Alternative biomass pre-processing
methods may also help to reduce the amount of contaminants
introduced into the process and lower purification costs. The
hydrolysate is further dewatered to increase the concentration of
sugars in the highly dilute hydrolysate stream (typical range of
sugar concentration is 10-15 wt %). The excess water which is
unreactive, results in higher heating requirements and larger
process equipment. A vacuum evaporator is utilized to increase
sugar concentrations while minimizing sugar degradation.
[0349] The purified hydrolysate slurry is sent to the catalytic
conversion process. The first step in the conversion is the aqueous
phase reforming (APR or APD/H) process, which takes the wide range
of solubilized carbohydrate stream and utilizes heterogeneous
catalysis to reduce the oxygen content of the feedstock. The
reactions in this step include reforming to generate hydrogen,
dehydrogenation of alcohols/hydrogenation of carbonyls,
deoxygenation reactions, hydrogenolysis, and cyclization. This
process is operated at 175.degree.-300.degree. C., 145-1,300 psi.
The reactor effluent is sent to the acid condensation reactor,
where conversion over a tailored catalyst such as ZSM-5 can result
in for example, a gasoline-range blendstock. To obtain high
selectivity for certain types of fuels, a catalyst that helps
generate hydrocarbons with low oxygen content and with the
appropriate amount of branching, cyclic, and aromatic content can
be used. The catalyst should be able to deal with a wide range of
sugars and contaminants, including sulfur, nitrogen and ash. In
addition, the ideal catalyst should be able to handle lignin and
its decomposed products with high carbon efficiency and long
catalyst lifetime. This process can also be used to produce
hydrocarbon "drop-in" fuels.
[0350] The product of the catalytic conversion process is sent to
fractionation where it is separated to various hydrocarbon
blendstocks. Plant wastewater streams are treated by anaerobic and
aerobic digestion. The methane-rich biogas from anaerobic digestion
can be sent to the combustor, where sludge from the digesters is
also burned. The treated water is suitable for recycling and is
returned to the process. The solids from hydrolysate purification
and wastewater treatment and the biogas from anaerobic digestion
can be combusted to produce high pressure steam for electricity
production and process heat. The boiler produces excess steam that
can be converted to electricity for use in the plant and for sale.
FIG. 5 is a schematic block diagram illustrating the conversion of
biomass to biofuel through the aqueous phase reforming/dehydration
and dehydrogenation of polyols. In an initial step (501), the
method includes, optionally, mechanically treating a cellulosic
and/or lignocellulosic feedstock. Before and/or after this
treatment, the feedstock can be treated with another physical
treatment (503), for example irradiation, sonication, steam
explosion, oxidation, pyrolysis or combinations of these, to reduce
or further reduce its recalcitrance. A sugar solution e.g.,
including glucose, xylose and combinations of these, is formed by
saccharifying the feedstock (504). The saccharification can be, for
example, accomplished efficiently by the addition of one or more
enzymes, e.g., cellulases and xylanases (502) and/or one or more
acids in any order.
[0351] Alternatively, the sugar solution can be bioprocessed (505),
for example by utilizing an organism to ferment the sugars to a
smaller saccharides, such as monosaccharides (eg., glucose and
xylose). These smaller sugars are then hydrogenated (preferably
catalytically) in step 506 to reduced sugars or polyols such as
sorbitol and xylitol. The resulting hydrosylate slurry is purified
through a number of processes such as centrifugation or filtration
in step 507. The purified hydrolysate slurry is subjected to
catalytic conversion process in step 508. This step involves
aqueous phase reforming (APR or APD/H) process, which takes the
wide range of solubilized carbohydrate stream and utilizes
heterogeneous catalysis to reduce the oxygen content of the
feedstock. The product of the catalytic conversion process is sent
to fractionation in step 509, where it is separated to various
biofuel blendstocks. FIG. 6 is a schematic block diagram
illustrating the conversion of biomass to biofuel through the
aqueous phase reforming/dehydration and dehydrogenation of polyols,
further including the catalytic conversion of longer polyols to
shorter polyols. In an initial step (601) the method includes,
optionally, mechanically treating a cellulosic and/or
lignocellulosic feedstock. Before and/or after this treatment, the
feedstock can be treated with another physical treatment (603), for
example irradiation, sonication, steam explosion, oxidation,
pyrolysis or combinations of these, to reduce or further reduce its
recalcitrance. A sugar solution e.g., including glucose, xylose and
combinations of these, is formed by saccharifying the feedstock
(604). The saccharification can be, for example, accomplished
efficiently by the addition of one or more enzymes, e.g.,
cellulases and xylanases (602) and/or one or more acids in any
order. Alternatively, the sugar solution can be bioprocessed (605),
for example by utilizing an organism to ferment the sugars to a
smaller saccharides, such as monosaccharides (eg., glucose and
xylose). These smaller sugars are then hydrogenated (preferably
catalytically) in step 606 to reduced sugars or polyols such as
sorbitol and xylitol. The reduced sugars can be further
catalytically converted to shorter polyols such as glycerol and
ethylene glycol in step 607. The resulting hydrosylate slurry is
purified through a number of processes such as centrifugation or
filtration in step 608. The purified hydrolysate slurry is
subjected to catalytic conversion process in step 609. This step
involves aqueous phase reforming (APR or APD/H) process, which
takes the wide range of solubilized carbohydrate stream and
utilizes heterogeneous catalysis to reduce the oxygen content of
the feedstock. The product of the catalytic conversion process is
sent to fractionation in step 610, where it is separated to various
biofuel blendstocks and other value-added products.
Isomerization and Fractionation of Hydrocarbons
[0352] The hydrocarbon molecules produced by any of the processes
described herein are often in mixtures, and are separated in a
fractionation process to components specifically tailored towards
various fuels such jet, gasoline, and diesel fuels. Depending upon
the carbon content of the hydrocarbons generated by the already
described process they can be used in different types of fuels. For
example, C8-C16 hydrocarbons are suitable for jet fuels, C9-C22
hydrocarbons may be suitable for diesel, and C4-C12 hydrocarbons
may be used for making gasoline.
[0353] FIG. 9A provides a graphical description of the distribution
of hydrocarbons of various carbon content in the hydrocarbon
mixture that may be generated, and/or further processed during the
catalytic conversion of biomass-derived building blocks. In some
embodiments, the lower gaseous hydrocarbons such as C3 and C4 may
be further converted to higher liquid hydrocarbons such as C8-C20
hydrocarbons. In some embodiments, the hydrocarbons can be
converted to corresponding cyclic or aromatic compounds, suitable
for use in certain types of fuel such as BTX. In some embodiments,
heavier hydrocarbons are converted to lighter hydrocarbons by
using, for example, Fluidized Catalytic Crackers (FCCs), Cokers,
Hydrocrackers, or Catalytic Reformers.
[0354] FIG. 9B provides a graphical description of the distribution
of hydrocarbons of various carbon content in the hydrocarbon
mixture that has been subjected to catalytic processing to convert
lower molecular hydrocarbons (typically gases) to higher molecular
weight hydrocarbons (typically liquid). For example, the figure
shows that after catalytic conversion, lower hydrocarbons such as
C3 and C4 may be further converted to higher hydrocarbons such as
C5-C12. In some embodiments, the conversion of lower hydrocarbons
to higher hydrocarbons is accomplished by using C--H activation
catalysts. In some embodiments, the higher hydrocarbons resulting
from the conversion of lower hydrocarbons constitute at least about
50% by weight, about 55% by weight, about 60% by weight, about 65%
by weight, about 70% by weight, about 75% by weight, about 80% by
weight, about 85% by weight, about 90% by weight, about 95% by
weight, and about 99% by weight of the hydrocarbon mixture after
catalytic conversion. In one embodiment, the amount of C1-C4 is
less than 5% by weight of the mixture of hydrocarbons after the
catalytic conversion of lower hydrocarbons to higher
hydrocarbons.
[0355] To meet the jet fuel specification, the produced bio-fuel
can have a high flash point, and good cold flow properties.
Therefore, some alkanes such as n-pentane and n-hexane can be
hydrocracked and hydroisomerized to produce the desired alkanes.
The cracking and isomerization reactions are either concurrent or
sequential. The isomerization process takes the straight-chain
hydrocarbons and turns them into the branched structures to reduce
the freeze point to meet the jet fuel standard. The conversion
takes place in the presence of acidic catalysts, generally
chlorinated alumina, that require strong drying of the feeds
upstream of the process. Bifunctional catalysts containing metallic
sites for hydrogenation/dehydrogenation and acid sites for skeletal
isomerization via carbenium ions are used in isomerization. In a
typical isomerization reaction, normal paraffins are dehydrogenated
on the metal sites of the catalyst and reacting on the acid sites
to produce protonated olefins with formation of the alkylcarbenium
ion. The alkylcarbenium ion is rearranged to monobranched,
dibranched, and tribranched alkylcarbenium ions on the acid site.
The branched alkylcarbenium ions are deprotonated and hydrogenated
to produce the corresponding paraffins. Isomerization can be
accompanied by a hydrocracking reaction, which results in more or
less yield from the isomerized species. The hydrocracking reactions
are exothermic and result in the production of lighter liquids and
gas products. They are relatively slow reactions; thus, most of the
hydrocracking takes place in the last section of the reactor. The
hydrocracking reactions primarily involve cracking and saturation
of paraffins. Overcracking will result in low yields of
jet-fuel-range alkanes and high yields of light species ranging
from C1 to C4 and naphtha ranging from C5 to C8. Both of these are
out of jet fuel range and also have lower economic value than
diesel or jet fuel.
[0356] In some embodiments, the conversion of lower hydrocarbons to
higher hydrocarbons is accomplished by using C--H activation
catalysts. Carbon-hydrogen bond activation is a type of reaction in
which a carbon-hydrogen bond is cleaved and replaced with a
carbon-X bond (where X is usually carbon, oxygen, or nitrogen). For
example, C--H bond activating catalysts may be used to convert a
low molecular weight hydrocarbon like butane to a high molecular
weight hydrocarbon like octane. Examples of C--H bond activating
catalysts include transition metal catalysts such as Rhodium-based
catalysts (eg., Cp*(Me.sub.3P)RhH.sub.2, Cp*(CO).sub.2Rh where Cp*
is pentamethylcyclopentadienyl), Iridium-based catalysts (eg.,
Cp*(Me.sub.3P)IrH.sub.2, Cp*(CO).sub.2Ir), Platinum-based catalysts
(eg., PtCl.sub.6.sup.2-, [(N--N)Pt(CH.sub.3)(solv)].sup.+, where
N--N is a bidentate nitrogen-centered ligand and `sols` is a weakly
coordinating solvent), Tungsten-based catalysts (eg.,
Cp*W(CO).sub.3(Bcat'), Cp.sub.2WH.sub.2,
Cp*W(NO)(.eta.3-allyl)(CH.sub.2CMe.sub.3) where cat' is
3,5-dimethylcatecholate, and Cp is cyclopentadienyl), Rhenium-based
catalysts (eg., Cp*Re), Ruthenium-based catalysts (eg.,
[Cp*RuCl.sub.2].sub.2), Titanium-based catalysts (eg.,
Ti(NMe.sub.2).sub.4), Iron-based catalysts (eg., Ferric catalysts
using ligands such as N, N'-Dimethylethylenediamine (DMEDA),
acetylacetonate (acac)), and Osmium-based catalysts (eg.,
OSO.sub.4, OsCl.sub.3 alone or in the presence of nitrogenated
ligands such as 2,5-dichloropyridine or 2,2'-bipyridine).
[0357] In some embodiments, catalytic conversion of lower
hydrocarbons to higher hydrocarbons may result in the conversion of
at least about 50% by weight, about 55% by weight, about 60% by
weight, about 65% by weight, about 70% by weight, about 75% by
weight, about 80% by weight, about 85% by weight, about 90% by
weight, about 95% by weight, about 99% by weight, and about 99.9%
by weight of lower hydrocarbons to higher hydrocarbons.
[0358] In some embodiments, the hydrocarbon mixture produced by the
processes described herein can have a ratio of saturated
hydrocarbons (such as alkanes and cycloalkanes) to unsaturated
hydrocarbons (such as alkenes and arenes) of greater than 1,
greater than 2, greater than 3, greater than 4, greater than 5,
greater than 6, greater than 7, greater than 8, greater than 9,
greater than 10, greater than 11, greater than 12, greater than 13,
greater than 14, greater than 15, greater than 16, greater than 17,
greater than 18, greater than 19, greater than 20, greater than 25,
greater than 30, greater than 35, greater than 40, greater than 45,
greater than 50, greater than 55, greater than 60, greater than 65,
greater than 70, greater than 75, greater than 80, greater than 85,
greater than 90, greater than 95, and greater than 100. In one
embodiment, the ratio of saturated to unsaturated hydrocarbons is
greater than 3.
[0359] In some embodiments, the amount of unsaturated hydrocarbons
in the hydrocarbon mixture produced by the processes described
herein is less than about 50% by weight, less than about 45% by
weight, less than about 40% by weight, less than about 35% by
weight, less than about 30% by weight, less than about 25% by
weight, less than about 20% by weight, less than about 15% by
weight, less than about 10% by weight, less than about 5% by
weight, and less than about 1% by weight.
[0360] In some embodiments, the hydrocarbon mixture produced by the
processes described herein can have a ratio of aromatic compounds
to non-aromatic compounds of less than 1, less than 0.9, less than
0.8, less than 0.7, less than 0.6, less than 0.5, less than 0.4,
less than 0.3, less than 0.2, less than 0.1, less than 0.09, less
than 0.08, less than 0.07, less than 0.06, less than 0.05, less
than 0.04, less than 0.03, less than 0.02, less than 0.01, and less
than 0.001. In one embodiment, the ratio of aromatics to
non-aromatic compounds is less than 0.4.
[0361] In some embodiments, the amount of aromatic compounds in the
hydrocarbon mixture produced by the processes described herein is
less than about 50% by weight, less than about 45% by weight, less
than about 40% by weight, less than about 35% by weight, less than
about 30% by weight, less than about 25% by weight, less than about
20% by weight, less than about 15% by weight, less than about 10%
by weight, less than about 5% by weight, and less than about 1% by
weight.
[0362] In some embodiments, the hydrocarbon mixture produced by the
processes described herein can have less than about 50% by weight
of C1-C4, less than about 45% by weight of C1-C4, less than about
40% by weight of C1-C4, less than about 35% by weight of C1-C4,
less than about 30% by weight of C1-C4, less than about 25% by
weight of C1-C4, less than about 20% by weight of C1-C4, less than
about 15% by weight of C1-C4, less than about 10% by weight of
C1-C4, less than about 5% by weight of C1-C4, and less than about
1% by weight of C1-C4.
[0363] In some embodiments, the hydrocarbon mixture produced by the
processes described herein can have greater than about 50% by
weight of C5-C18, greater than about 55% by weight of C5-C18,
greater than about 60% by weight of C5-C18, greater than about 65%
by weight of C5-C18, greater than about 70% by weight of C5-C18,
greater than about 75% by weight of C5-C18, greater than about 80%
by weight of C5-C18, greater than about 85% by weight of C5-C18,
greater than about 90% by weight of C5-C18, greater than about 95%
by weight of C5-C18, and greater than about 99% by weight of
C5-C18.
[0364] It has been observed that the hydrocarbon mixture produced
by some of the processes described herein contain a higher amount
of even-numbered hydrocarbons than odd-numbered hydrocarbons.
Without being bound by hypothesis, it is possible that the
even-numbered hydrocarbons are produced by the oligomerization of
ethylene molecules, and odd-numbered hydrocarbons are produced via
metal-carbon double bond (M=CH.sub.2) species. It is also
hypothesized that cracking may enhance the production of
odd-numbered hydrocarbons. Thus, in some embodiments, the
production of even-numbered hydrocarbons is facilitated by lowering
the heat applied to the catalytic reactors converting
biomass-derived building blocks to hydrocarbons. For example, the
catalytic conversion described above may be done at about a
temperature of about 50.degree. C. to about 100.degree. C., about
100.degree. C. to about 150.degree. C., about 150.degree. C. to
about 200.degree. C., about 200.degree. C. to about 250.degree. C.,
about 250.degree. C. to about 300.degree. C., about 300.degree. C.
to about 350.degree. C., about 350.degree. C. to about 400.degree.
C., or in a range bounded by any numerical value stated herein
above.
[0365] In some embodiments, the ratio of even-numbered hydrocarbons
to odd-numbered hydrocarbons in the hydrocarbon mixture produced by
the processes described herein can be greater than 1, greater than
2, greater than 3, greater than 4, greater than 5, greater than 6,
greater than 7, greater than 8, greater than 9, greater than 10,
greater than 11, greater than 12, greater than 13, greater than 14,
greater than 15, greater than 16, greater than 17, greater than 18,
greater than 19, greater than 20, greater than 25, greater than 30,
greater than 35, greater than 40, greater than 45, greater than 50,
greater than 55, greater than 60, greater than 65, greater than 70,
greater than 75, greater than 80, greater than 85, greater than 90,
greater than 95, and greater than 100.
[0366] In some embodiments, the amount of odd-numbered hydrocarbons
in the hydrocarbon mixture produced by the processes described
herein is less than about 50% by weight, less than about 45% by
weight, less than about 40% by weight, less than about 35% by
weight, less than about 30% by weight, less than about 25% by
weight, less than about 20% by weight, less than about 15% by
weight, less than about 10% by weight, less than about 5% by
weight, and less than about 1% by weight.
[0367] The hydro-isomerization and hydrocracking processes are
followed by a fractionation process to separate the mixtures to
paraffinic kerosene, paraffinic diesel, naphtha, and light gases.
The lighter alkanes such as C1-C4 hydrocarbons, are sent to the
combustor to provide additional process heat. The heavier species
of the products can be distilled and blended into jet fuel. One of
the byproducts of the isomerization process is glycerol, which has
many pharmaceutical, technical, and personal care product
applications. Closed loop processes that recover and recycle the
unreacted species are significant to improve the process
economics.
Biorefinery
[0368] In one aspect, the methods and products described herein are
part of a biorefinery concept. The biorefinery embraces a wide
range of technologies able to convert biomass into certain building
blocks (alcohols, hydrocarbons, carbohydrates, proteins,
triglycerides etc.), which can be converted to value added
products, biofuels and chemicals. Analogous to the petroleum
refinery, a biorefinery is a facility (or network of facilities)
that integrates biomass conversion processes and equipment to
produce transportation biofuels, power, and chemicals from biomass.
It involves the sustainable processing of biomass into a spectrum
of marketable products and energy.
[0369] The products of biorefinery systems can be grouped in two
broad categories: material products and energy products. Energy
products are those products which are used because of their energy
content, providing electricity, heat or transportation service. On
the other hand, material products are not used for an energy
generation purpose but for their chemical or physical
properties.
[0370] FIG. 11 provides a schematic block diagram illustrating the
conversion of biomass to various fuel, fuel-components, and other
value-added products. For example, mixtures of hydrocarbons and
other compounds derived from biomass through various processes
described herein, can be further subjected to separation, and
modification to produce various types of end-products. They can be
separated, for example, by various types of distillation and gas
separation methods to gaseous components, light naphtha, heavy
naphtha, light vacuum gas oil (LVGO), heavy vacuum gas oil (HVGO),
atmospheric gas oil (AGO), kerosene, coke and other components.
These components may be then subjected to various processes such as
isomerization, hydro-treating, distillation, coking, catalytic
cracking, reforming, hydro-cracking, solvent deasphalting,
visbreaking, solvent dewaxing, polymerization, alkylation etc. to
convert them to other value-added products or intermediates or
components of value-added products, such as coke, waxes, greases,
lubricants, asphalts, residual fuel oils, diesel, heating oils,
solvents, kerosene, jet fuels, solvents, automotive gasoline,
aviation gasoline, LPG fuel gas, and sulfur.
[0371] Examples of energy products include gaseous fuels (eg.,
biogas, syngas, hydrogen, methane, etc.), solid fuels (eg., coke,
pellets, lignin etc.), and liquid fuels (eg., ethanol, diesel, jet
fuel etc.).
[0372] Gases generated during the processes described herein can be
used as energy source within the biorefinery system as well as
outside it. For example, the gaseous fuel can be diverted to a
combustion engine connected to an electric generator to produce
electricity. It can also be used as a fuel source for a
spark-ignited natural gas engine. As another example, the gas can
be used as a fuel source for a direct-injection natural gas engine.
As another example, the gas can be used as a fuel source for a
combustion turbine.
[0373] In some embodiments biogases arising from the anaerobic
fermentation of biomass and the gasification of solid biomass
(including biomass in wastes) can be used as fuel to support other
processes in the pipeline or as a chemical feedstock. The biogases
from anaerobic fermentation are composed principally of methane and
carbon dioxide and comprise landfill gas, sewage sludge gas and
other biogases from anaerobic fermentation. Biogases can also be
produced from thermal processes (by gasification or pyrolysis) of
biomass and are mixtures containing hydrogen and carbon monoxide
(usually known as syngas) along with other components. These gases
may be further processed to modify their composition and can be
further processed to produce substitute natural gas. The gases are
divided into two groups according to their production: biogases
from anaerobic fermentation and biogases from the thermal
processes.
[0374] Multiple gasification technologies exist to convert
reduced-size biomass to syngas. In one embodiment, a
high-temperature (slagging) gasification process is used, wherein
the biomass is pressurized and converted into raw synthesis gas
during gasification at temperatures around 1300.degree. C. in the
presence of high purity oxygen and steam. A combustor is included
to provide heat to dry the biomass. A direct-quench syngas cooling
system next to the gasifier removes ash and tars. A water-gas-shift
system after quench is applied to adjust the H.sub.2:CO ratio to
2.1:1. In another embodiment, the endothermic gasification process
is indirectly heated by the circulation of hot olivine and the
material in the gasifier is fluidized by the steam. Gasification
occurs at atmospheric conditions and at 880.degree. C. The syngas
is further conditioned such that the residual tars, methane and
light hydrocarbons are reformed to syngas in a fluid catalytic
cracker. Water gas shift also occurs in the reformer. Compared to
the high temperature gasification, this design has the benefits of
energy self-sufficient, improved capital cost associated with the
smaller process scale, and neutral electrical energy. Syngas can be
used directly as a stationary biofuel or can be a chemical
intermediate (platform) for the production of fuels (FT-fuels,
dimethyl ether, ethanol, isobutene., etc.) or chemicals (alcohols,
organic acids, ammonia, methanol, etc.).
[0375] Gasification and reforming pathways starting from biomass
can also provide hydrogen. There are a number of processes for the
production of hydrogen from carbon-containing feedstocks, such as
catalytic steam reforming (SR), autothermal reforming (AR) and
partial oxidation (PO), as well as other configurations, which
contain various aspects of any of the aforementioned processes. In
addition, methane can be cracked into hydrogen and carbon; for
higher hydrocarbons, cracking reactions also come into play, and
heteroatoms, which are almost invariably present in the feedstocks,
react as well under the conditions of the hydrogen-generating
reactions. Hydrogen can also be generated during the fermentation
process.
[0376] In some embodiments, refinery gas is generated by the
processes described herein. Refinery gas typically includes a
mixture of non-condensable gases mainly consisting of hydrogen,
methane, ethane and olefins obtained during distillation of
hydrocarbon products (e.g. cracking). It is used mainly as a fuel
within the refinery.
[0377] In some embodiments, solid fuel can be generated from the
processes described herein. For example, coke generated during the
processes described herein can be used as fuel for other processes
described herein or can be commercialized. Coke can also be
obtained by cracking and carbonizing the hydrocarbon products
generated by the processes described herein. The two most important
categories are "green coke" and "calcined coke." Green coke (raw
coke) is the primary solid carbonisation product from high boiling
hydrocarbon fractions obtained at temperatures below 630.degree. C.
It contains 4-15 percent by weight of matter that can be released
as volatiles during subsequent heat treatment at temperatures up to
approximately 1330.degree. C. Calcined coke is obtained by heat
treatment of green coke to about 1330.degree. C. It will normally
have a hydrogen content of less than 0.1 percent by weight. Coking
processes that can be employed for making coke can include contact
coking, fluid coking, flexicoking and delayed coking. For example,
in some embodiments, a Delayed Coker is used to convert the heavy
material, resid, at the bottom of a vacuum bed tower into more
valuable products. The delayed coker uses high temperature to break
the hydrocarbon chains into smaller hydrocarbons, which can then be
reformed into high-value hydrocarbons. Delayed coking also produces
coke as a by-product.
[0378] In some embodiments, carbon is isolated from biomass by the
processes described herein. The carbon thus produced can be used in
other value-added products, or as a building blocks for other
value-added products. For example, carbon in the form of charcoal
and coke can be used in metal smelting, in industries such as the
iron and steel industries. Carbon in the form of graphite can be
used in pencils, to make brushes in electric motors and in furnace
linings. Activated charcoal can be used for purification and
filtration, example in respirators and kitchen extractor hoods.
Carbon fiber generated from carbon can be used strong, yet
lightweight, material in many products such as tennis rackets,
skis, fishing rods, rockets and airplanes. Carbon can also be used
to prepare carbon nanotubes, fullerenes and atom-thin sheets of
graphene, which can be used for example, in hardware developments
in the electronics industry and in nanotechnology.
[0379] In some embodiments, lignin liberated in any process
described herein can be captured and utilized. In some instances,
it can be utilized as an energy source, e.g., burned to provide
heat. In some instances, it can also be converted to
lignosulfonates, which can be utilized as binders, dispersants,
emulsifiers or as sequestrants. Lignin-containing residues from
primary and pretreatment processes have value as a high/medium
energy fuel and can be used to generate power and steam for use in
plant processes. In some cases, gasification of the lignin residues
can convert it to a higher value product with lower cost. As a
heating source, lignin generally has a higher energy content than
holocellulose (cellulose and hemicellulose) since it contains more
carbon than holocellulose. For example, dry lignin can have an
energy content of between about 11,000 and 12,500 BTU per pound,
compared to 7,000 an 8,000 BTU per pound of holocellulose. Lignin
can be densified and converted into briquettes and pellets for
burning. For example, the lignin can be converted into pellets by
any method described herein. For a slower burning pellet or
briquette, the lignin can be crosslinked, such as by applying a
radiation dose of between about 0.5 Mrad and 5 Mrad. Crosslinking
can provide a slower burning form factor. The form factor, such as
a pellet or briquette, can be converted to a "synthetic coal" or
charcoal by pyrolyzing in the absence of air, e.g., at between 400
and 950.degree. C. Prior to pyrolyzing, it can be desirable to
crosslink the lignin to maintain structural integrity.
Lignocellulosic biomass in its original form usually have a low
bulk density of 30 kg/m.sup.3 and a moisture content ranging from
10% to 70%. Pelleting increases the specific density (gravity) of
biomass to more than 1000 kg/m.sup.3. Pelleted biomass is low and
uniform in moisture content. It can be handled and stored cheaply
and safely using well developed handling systems for grains.
[0380] In some embodiments, the sludge, and post-distillate solids
can be burned to heat water flowing through a heat exchanger. In
some embodiments, the water flowing through the heat exchanger is
evaporated and superheated to steam. The steam can be used, for
example, in a pretreatment reactor. Additionally, or alternatively,
the steam expands to power a multi-stage steam turbine connected to
an electric generator. Steam exiting the steam turbine is condensed
with cooling water and returned to the heat exchanger for reheating
to steam.
[0381] A number of other compounds produced by processing a
cellulosic and/or lignocellulosic biomass can act as building
blocks for a large number of biochemical products that can be used
in the textile industry (eg., in making carpets, fibers, fabrics
etc.), food industry (eg., in food packaging, preservatives etc.),
transportation industry (eg., in making tires, molded plastics
etc.), housing industry (eg., in making paints, resins, cements,
garbage bags, glue etc.), furnitures, sports industry (eg., in
making athletic gears, balls, roller blades, camera films etc.),
communications industry (eg., in making dyes, fiber coatings),
cosmetic industry (eg., perfumes, deodarants, shampoos, toothpaste
etc.) and health industry (eg., in making medical devices and
pharmaceuticals).
[0382] For example, ethylene can be an important building block in
the biochemical, biopolymers and plastic industry, given that six
major polymer classes can be derived from ethylene (PE, PET, PEG,
PVA, PVC, PS). Propanol can be converted to propylene, which is
also an important intermediate for producing polypropylene,
acrylamide and propylene glycol. Propanol can also be used as a
building block for isoprene, acrylonitrile, acrylamide, acrolein,
propylene oxide, and glycidol. Lactic acid is a precursor of
polylactic acid (PLA), lactate esters, and peroxyacetic acid.
[0383] Another precursor, glycerol, can be a source of a wealth of
downstream products, such as acetol, 3-hydroxypropionaldehyde
(3-HPA), 3-HP(acid) epicholohydrin, docosahexanoic acid,
3-hydroxypropanal, mesoxalic acid, glycolic acid, hydroxypyruvic
acid, propylene glycol, ethylene glycol, glycerol carbonate,
glycidol, acrolein, acrylic acid, malonic acid, propiolactone,
polyglycidol and methyl acrylate.
[0384] Succinic acid can be used to generate a large range of
products including poly(butylenesuccinate) (PBS), THF and poly
(THF), acrylonitrile, succinonitrile, putrescine,
poly(butyleneterephthalate) (PBT), and a range of acid and amine
compounds.
[0385] Buta-1,3-diene can be used in producing furan, adipic acid,
hexane 1,6-diol, hexane 1-6-diamine, styrene, and
poly(butylenesuccinate) (PBS).
[0386] Isobutanol can be used as a starting point for the important
intermediate of isobutylene, for para-xylene, and polyisobutylene
(PIB). It can also be used to make a number of other value-added
products such as polymers of methacrylic acid (eg., PMMA), isoprene
(eg., polyisoprene), and urethanes (PU).
[0387] C5 sugars can be used in the production of furfural, and
then furfuryl alcohol to produce levulinic acid, or furan for THF.
Levulinic acid can act as a starting "feedstock" for several
downstream products (such as pentane 1,4-diol, butene (which can be
converted into diesel, jet or petrol alkanes) via
.delta.-Valerolactone. Xylose and arabinose, for example, can be
used to produce xylitol and arabinotol respectively, which can be
reacted under hydrogenolysis conditions to produce ethylene
glycol.
[0388] C6 sugars such as glucose and fructose can be dehydrated to
produce 5-hydroxymethylfurfural (5-HMF), which can produce
value-added products such as para-xylene and 2,5-furandicarboxylic
acid (FDCA)(which can then produce polymers such as
polyethylenefuranoate (PEF) and polybutylenefuranoate (PBF)).
Glucose can also be converted to adipic acid (an important monomer
for nylons), and sorbitol (which can be used to produce isosorbide
and polycarbonates).
[0389] Sugars with reduced recalcitrance can also be converted to
hydrocarbon fuel through the formation of terpenes. Terpenes can be
generated from the bioconversion of fermentable sugars derived from
lignocellulosic biomass using organisms such as E. coli or S.
cerevisiae. There are at least two known metabolic pathway for the
generation of terpenes and their precursors, isopentenyl
pyrophosphate (IPP): the mevalonic acid (MVA) pathway and the
deoxyxylulose-phosphate (DXP) pathway. The terpenes, assembled by
condensing IPP and its isomer dimethylallyl pyrophosphate,
represent the candidates of biologically-derived fuel. Large
terpenes can be cracked to liquid fuel and the branched olefins can
be hydrogenated to isoparaffins.
[0390] In some embodiments, the reduced recalcitrance sugar is
processed through the MVA pathway and converted into artemisinic
acid, isopentenyl pyrophosphate, and jet/gasoline precursors. The
artemisinic acid is then turned into an anti-malarial drug, and
isopentenyl pyrophosphate is further transformed into farnesenyl
pyrophosphate and C15 isoprenoids, which are the precursors of
diesel and chemicals. The fermentation waste could be optionally
processed with anaerobic digestion to reduce the effluent. After
purification, through downstream hydro-processing, the jet/gasoline
precursors can be turned into bio-jet fuel.
[0391] In some embodiments, a two-stage process can be used to
convert sugar derived from biomass into 2,5-dimethylfuran (DMF).
The fructose, obtained directly from biomass or by isomerizing of
glucose, is dehydrated to form 5-hydroxymethylfurfural (HMF) by
removing five oxygen atoms over an acid catalyst. HMF is then
turned into DMF through hydrogenolysis over a CuRu catalyst. DMF
has a number of attractions as a biofuel. It has higher energy
density by 40% and a higher boiling point by 20 K than ethanol.
Since it is water insoluble it does not absorb moisture from the
atmosphere.
[0392] Methods of obtaining organic acids have already been
described. The organic acids produced by the processes described
herein can include monocarboxylic acids or a polycarboxylic acids.
Examples of organic acids include formic acid, acetic acid,
propionic acid, butyric acid, valerie acid, caproic, palmitic acid,
stearic acid, oxalic acid, malonic acid, succinic acid, glutaric
acid, oleic acid, linoleic acid, glycolic acid, lactic acid,
.gamma.-hydroxybutyric acid or mixtures of these acids. These
organic acids can also serve as building blocks of other
compounds.
[0393] In some embodiments, the organic acids that can be produced
are further converted to other compounds such as aspartic acid,
glutamic acid and the amino substituted malonic, adipic, pimelic,
suberic, azelaic and sebacic acids or their corresponding acidic or
basic salts, e.g., their Na.sup.+, K.sup.+, Ca.sup.2+, or ammonium
salts and mixtures of salts and acids. In one implementation of the
method, the amino-alpha, omega-dicarboxylic acids are converted
chemically or biochemically, for example, by converting aspartic
acid or glutamic acid to the respective polyamides. Other methods
of chemically converting that can be utilized include
polymerization, isomerization, esterification, amidation,
cyclization, oxidation, reduction, disproportionation and
combinations of these.
[0394] In some embodiments, converting comprises polymerizing an
acid, such as aspartic or glutamic acid to a polymer (e.g.,
polymerizing in a melt such as without an added solvent). For
example, polymerizing methods can be selected from direct
condensation of the aspartic or glutamic acid, azeotropic
dehydrative condensation of the aspartic or glutamic acid, and
cyclizing the aspartic or glutamic acid followed by ring opening
polymerization. The polymerization can be in a melt (e.g., without
a solvent and above the melting point of the polymer) or can be in
a solution (e.g., with an added solvent). A polyamide can be a
product of the polymerization process. Optionally, polymerizations
can be done utilizing catalysts and/or promoters. For example,
protonic acids, H.sub.3PO.sub.4, H.sub.2SO.sub.4, methane sulfonic
acid, p-toluene sulfonic acid, NAFION.RTM. NR 50 H+form from
DuPont, Wilmington Del., acids supported on polymers, Mg, Al, Ti,
Zn, Sn, metal oxides, TiO.sub.2, ZnO, GeO.sub.2, ZrO.sub.2, SnO,
SnO.sub.2, Sb.sub.2O.sub.3, metal halides, ZnCl.sub.2, SnCl.sub.2,
SnCl.sub.4, Mn(AcO).sub.2, Co(AcO).sub.2, Ni(AcO).sub.2,
Al(i-PrO).sub.3, Ti(BuO).sub.4, TiO(acac).sub.2, (Bu).sub.2SnO, tin
octoate, solvates and hydrates of any of these and mixtures of
these can be used.
[0395] Optionally, when the polymerization method is direct
condensation, the polymerization can include utilizing coupling
agents and/or chain extenders to increase the molecular weight of
the polymer. For example, the coupling agents and/or chain
extenders can include triphosgene, carbonyl diimidazole,
dicyclohexylcarbodiimide, diisocyanate, acid chlorides, acid
anhydrides, epoxides, thiirane, oxazoline, orthoester, and mixtures
of these. Alternatively, the polymer can have a co-monomer which is
a polycarboxylic acid polyamide or polyamines or a combination of
these.
[0396] In some embodiments, when polymers are made, the method can
further include branching and/or cross linking the polymer. For
example, the polymers can be treated with a cross linking agent
including 5,5'-bis(oxepane-2-one)(bis-.epsilon.-caprolactone)),
spiro-bis-dimethylene carbonate, peroxides, dicumyl peroxide,
benzoyl peroxide, unsaturated alcohols, hydroxyethyl methacrylate,
2-butene-1,4-diol, unsaturated anhydrides, maleic anhydride,
saturated epoxides, glycidyl methacrylate, irradiation and
combinations of these. Optionally, a molecule (e.g., a polymer) can
be grafted to the polymer. For example, grafting can be done
treating the polymer with irradiation, peroxide, crossing agents,
oxidants, heating or any method that can generate a cationic,
anionic or radicle on the polymer.
[0397] Lignin can also be used in ceramics, for binding carbon
black, for binding fertilizers and herbicides, as a dust
suppressant, in the making of plywood and particle board, for
binding animal feeds, as a binder for fiberglass, as a binder in
linoleum paste and as a soil stabilizer. As a dispersant, the
lignin or lignosulfonates can be used, e.g., concrete mixes, clay
and ceramics, dyes and pigments, leather tanning and in gypsum
board. As an emulsifier, the lignin or lignosulfonates can be used,
e.g., in asphalt, pigments and dyes, pesticides and wax emulsions.
As a sequestrant, the lignin or lignosulfonates can be used, e.g.,
in micro-nutrient systems, cleaning compounds and water treatment
systems, e.g., for boiler and cooling systems.
[0398] In addition the processes described herein can be used to
generate additives. In some embodiments, additives are blended with
oil products to modify their properties including modification of
octane number, cetane number, cold properties, lubricity,
viscosity, contaminants, and as antioxidants, stabilizers and
biocides. Examples of additives include oxygenates, such as
alcohols (methanol, ethanol), ethers (such as MTBE (methyl tertiary
butyl ether), ETBE (ethyl tertiary butyl ether), TAME (tertiary
amyl methyl ether), esters (e.g. rapeseed or dimethylester, etc.),
and other chemical compounds (such as TML, and TEL and detergents).
For example, Bioether (also referred to as fuel ethers or
oxygenated fuels) a fuel additive, which acts as octane rating
enhancers, can be one of the products generated by the processes
described herein. Bioethers can be obtained for example, by
processing a cellulosic and/or lignocellulosic biomass from sources
such as wheat. In some embodiments, iso-olefins (such as
iso-butylene) and ethanol derived from biomass can be reacted to
produce bioethers. Bioethers enhance engine performance, while
significantly reducing engine wear and toxic exhaust emissions. By
replacing petroethers in fuel blends, they can contribute to
improved air-quality by reducing pollutants and ozone emissions.
Examples of bioethers that can be produced by the processes
described herein include dimethyl ether (DME), diethyl ether (DEE),
methyl tertiary-butyl ether (MTBE), ethyl ter-butyl ether (ETBE),
ter-amyl methyl ether (TAME), and ter-amyl ethyl ether (TAEE).
[0399] Various types of additives can be produced from the building
blocks generated by the processes described herein. Examples
include detergent additives (used to clean and neutralize oil
impurities), corrosion or rust inhibiting additives (which retard
the oxidation of metal inside an engine), antioxidant additives
(which retard the degradation of the stock oil by oxidation), metal
deactivators (which create a film on metal surfaces to prevent the
metal from causing the oil to be oxidized), viscosity modifiers
(which modifies an oil's viscosity higher at elevated temperatures,
improving its viscosity index (VI)), friction modifiers or friction
reducers (eg., molybdenum disulfide, which are used for increasing
fuel economy by reducing friction between moving parts), extreme
pressure agents (which bond to metal surfaces, keeping them from
touching even at high pressure), anti-wear additives or wear
inhibiting additives (which cause a film to surround metal parts,
helping to keep them separated), dispersants (which keep
contaminants (e.g. soot) suspended in the oil to prevent them from
coagulating), anti-foam agents (which inhibit the production of air
bubbles and foam in the oil which can cause a loss of lubrication),
anti-misting agents (which prevent the atomization of the oil), and
wax crystal modifiers (which are dewaxing aids that improve the
ability of oil filters to separate wax from oil).
[0400] In some embodiments, the heavy fraction that sinks to the
bottom of vacuum towers in the process of separating the
hydrocarbons can be used to produce asphalt or bitumen. This heavy
material is also called Vacuum Tower Bottoms (VTB) or "resid." If
allowed to cool to room temperature, it would become a solid. This
can be used as a blend in asphalt. Asphalt consists of saturated
hydrocarbons (which correlate with softening point of the
material), naphthalene aromatics (consisting of partially
hydrogenated polycyclic aromatic compounds), polar aromatics (eg.,
high molecular weight phenols and carboxylic acids) and
asphaltenes, consisting of high molecular weight phenols and
heterocyclic compounds.
[0401] In some embodiments, the processes described herein can
result in the formation of lubricants. Lubricant base stocks are
obtained from vacuum distillates which result from further
distillation of the residue from atmospheric distillation of the
hydrocarbon oil. The lubricant base stocks are then further
processed to produce lubricants with the desired properties. In
some embodiments, paraffin waxes are extracted when dewaxing
lubricant oils. The waxes have a crystalline structure which varies
in fineness according to the grade and are colourless, odourless
and translucent, with a melting point above 45.degree. C. In some
embodiments, greases, which are semi-solid lubricants are obtained
from the processes described herein.
[0402] In some embodiments, food products or components of food
products are generated by the processes described herein. For
example, intermediate fermentation products include high
concentrations of sugar and carbohydrates. These intermediate
fermentation products can be used in preparation of food for human
or animal consumption. In some embodiments, irradiation
pretreatment of the cellulosic material will render the
intermediate fermentation products sterile (e.g., fit for human
consumption). In some embodiments, the intermediate fermentation
products will require post-processing prior to use as food. For
example, a dryer can be used to remove moisture from the
intermediate.
[0403] Distillers grains and solubles can be converted into a
valuable byproduct of the distillation-dehydration process. After
the distillation-dehydration process, distillers grains and
solubles can be dried to improve the ability to store and handle
the material. The resulting dried distillers grains and solubles
(DDGS) is low in starch, high in fat, high in protein, high in
fiber, and high in phosphorous. Thus, for example, DDGS can be
valuable as a source of animal feed (e.g., as a feed source for
dairy cattle). DDGS can be subsequently combined with nutritional
additives to meet specific dietary requirements of specific
categories of animals (e.g., balancing digestible lysine and
phosphorus for swine diets).
[0404] In some embodiments, the processes described above can be
used to produce materials, which can have therapeutic value or can
act as building blocks or components of pharmaceuticals or
neutriceuticals. For example, the pretreatment processes discussed
above can be applied to plants with medicinal properties. In some
embodiments, sonication can stimulate bioactivity and/or
bioavailabilty of the medicinal components of plants with medicinal
properties. Additionally or alternatively, irradiation stimulates
bioactivity and/or bioavailabilty of the medicinal components of
plants with medicinal properties. For example, sonication and
irradiation can be combined in the pretreatment of willow bark to
stimulate the production of salicin. In some embodiments,
intermediate fermentation products (e.g., products that include
high concentrations of sugar and carbohydrates) can be supplemented
to create a nutriceutical. For example, intermediate fermentation
products can be supplemented with calcium create a nutriceutical
that provides energy and helps improve or maintain bone
strength.
[0405] In some embodiments, the processes described herein can
generate products, such as fertilizers, soil amendments, and soil
regenerating products, or building blocks for their generation. For
example, the solids left over after the treatments at the biomass,
can be used as a fertilizer after drying. In some embodiments,
stripping, which is process where ammonia from the air is scrubbed
with sulphuric acid and recovered as a 40% TS (total solids, dry
matter) ammonium sulfate solution is used. Ammonium sulfate, thus
produced can be utilized in a fertilizer and/or for soil enrichment
production. In some embodiments, boiler and/or fly ash of the
facility may be used for drying the solid residue of the
biorefinery so that the residue may be used as a fertilizer. Adding
of boiler and/or fly ash in the fertilizer not only dries the
fertilizer by binding the water therein, but also improves the
properties of the fertilizer so that the resulting fertilizer may
be used not only as a fertilizer but also to replace the use of
potassium as the soil improving agent.
Catalytic Pyrolysis to Generate Aromatic Compounds
[0406] In one embodiment, catalytic fast pyrolysis (CFP) of
processed biomass is used to produce aromatic compounds such as
benzene, toluene and xylene, which could be used to generate TX.
BTX is a mixture of aromatic compounds, including benzene, toluene,
thiophene, ethylbenzene, p-xylene, m-xylene, o-xylene, and styrene,
and typically containing a low amount of non-aromatic compounds,
such as cylcopentane, and indene.
[0407] BTX can be used as fuel, fuel blend or additives. The
components of BTX can also act as building blocks of other
value-added products. For example, benzene can be converted to
polystyrene through ethylbenzene and styrene. Benzene may also be
converted to cumene, which can be modified to phenolic compounds,
which can serve as building blocks for phenolic resins, and
polycarbonates. Benzene can also form Nylon through cyclohexane and
caprolactams. Similarly, toluene can be used as a starting material
for making polyurethane and several gasoline components, p-xylene
could be used as a starting material for making polyester fibers
and resins, and o-xylene could be used to make phthalic
anhydride.
[0408] There are various ways of generating BTX and components
thereof from biomass. For example, the processed biomass can be fed
into a fluidized-bed reactor where it is thermally decomposed to
form pyrolysis vapors. These pyrolysis vapors then enter catalysts
(such as zeolites) present in the fluidized bed reactor, where they
get converted into the desired aromatic compounds and olefins along
with CO, CO.sub.2, H.sub.2O, and coke. In some embodiments, it may
be preferred to convert the pyrolysis vapors to aromatics outside
the pyrolysis reactor. The spent catalyst and coke can then be sent
to a regenerator where they can be burned to provide heat.
[0409] In some embodiments, naptha generated from biomass can be
treated in catalytic reformers under high temperature catalytic
dehydrogenation conditions to convert it into aromatics. These
reformers can produce large quantities of the primary aromatic
chemicals. Benzene, toluene, and a mixed xylene stream can be
subsequently recovered by extractive distillation using a solvent.
Recovery of various types of xylene from a mixed xylene stream
could be accomplished by a further processing step of
crystallization and filtration or adsorption followed by desorption
on beds of molecular sieves.
[0410] Pyrolysis of processed biomass can produce a mixture of
compounds such as anhydro sugars and olefins. The anhydro sugars
can undergo acid-catalyzed dehydration to furan-derivatives. The
furan can undergo either decarbonylation to form allene
(C.sub.3H.sub.4) and CO, or Diels-Alder condensation to form
benzofuran (C.sub.8H.sub.6O) and water. The allene can undergo
either oligomerization to form a series of olefins, or alkylation
with other aromatics to form heavier aromatics and ethylene. The
olefins can react with furan to form aromatics and water. The
benzofuran may also undergo decarbonylation to form benzene, CO,
and coke. The olefins produced during CFP can be recycled into the
reactor to form more aromatics. See Yu-Ting Cheng, et al.,
Production of Renewable Aromatic Compounds by Catalytic Fast
Pyrolysis of Lignocellulosic Biomass with Bifunctional Ga/ZSM-5
Catalysts, Angew. Chem. Int. Ed., 2012, 51, 1387-1390.
[0411] The yield and composition of the aromatic products can be
optimized by modifying the catalysts, the temperature, pressure,
ratio of biomass to catalysts and other factors. Various catalysts
can be used, such as ZSM-5/Zn/La, ZSM-5/Ga, Al-MSU-S Foam, HZSM,
MCM-41, .beta.-zeolite, sulfated zirconia (SO.sub.4.sup.2-
ZrO.sub.2), 20% SO.sub.4.sup.2- ZrO.sub.2 dispersed on a mesoporous
MCM-41 silica and support.
[0412] CFP has several advantages, including the fact that all the
desired chemistry can occur in one single reactor, it does not
require process hydrogen, typically needs low pressure and
inexpensive silica-alumina catalysts. FIG. 7 is a reaction scheme
of converting processed biomass to aromatic compounds. Pyrolysis of
processed biomass can produce a mixture of compounds such as
anhydro sugars and olefins. The anhydro sugars can undergo
acid-catalyzed dehydration to furan-derivatives. The furan can
undergo catalyzed oligomerization, decarboxylation, and/or
decarbonylation to form aromatic compounds. The olefins produced
during CFP can be recycled into the reactor to form more
aromatics.
Catalytic Systems and Processes
[0413] One or more of the catalytic conversion processes described
herein may be accomplished by zeolite or alumina supported
catalysts. For example, in some embodiments, ethanol derived from
the processing of lignocellulosic feedstock can be converted to a
hydrocarbon mixture by one or more zeolite or alumina-based
catalysts.
[0414] In some embodiments, alumina (e.g., high purity
.gamma.-alumina, 150-200 m.sup.2/g) can be used as the support for
catalyst preparation. Various metals can be used for the catalyst
preparation, such as Pt, Pd, Sn, Re, Rh, Bi, Ba, Ti, Ni, and
combinations thereof. The catalyst prepared could be mono-metallic
catalyst, bi-metallic catalyst, or tri-metallic catalyst. In some
embodiments, the catalyst can be prepared by an incipient wetness
impregnation method using the desired salt solution. After
impregnation of the support with the appropriate metal salt, the
catalyst samples can be dried at room temperature, followed by oven
drying. Finally, the catalysts can be calcined under air, for
example, at 500.degree. C.
[0415] In some embodiments, acidified alumina catalysts can be used
as the support for metal catalyst preparation. For example, alumina
can be pre-treated with acids such as H.sub.3BO.sub.3,
H.sub.3PO.sub.4, HCl, H.sub.2SO.sub.4, citric acid, oxalic acid, or
acetic acid. The amount of acid present in the pre-treated catalyst
can vary, and can be about 0.1% to about 1%, about 1% to about 5%,
about 5% to about 10%, about 10% to about 20%, about 20% to about
30%, about 30% to about 40%, about 40% to about 50%, about 50% to
about 60%, about 60% to about 70%, about 70% to about 80%, about
80% to about 90% by weight, or in any numerical range stated
hereinabove. After the treatment with acid, the acid-treated
Al.sub.2O.sub.3 support can be dried at room temperature, followed
by oven drying, and calcined under air, for example, at 500.degree.
C. In the second step, incipient wetness impregnation method can be
used for the preparation of metal-modified catalyst. Various metals
can be used for the catalyst preparation, such as Pt, Pd, Sn, Re,
Rh, Bi, Ba, Ti, Ni, and combinations thereof. The catalyst prepared
could be a mono-metallic catalyst, bi-metallic catalyst, or
tri-metallic catalyst. After impregnation with the appropriate
salt, the catalyst samples can be dried at room temperature,
followed by oven drying. Finally, the catalysts can be calcined
under air, for example, at 500.degree. C.
[0416] In some embodiments, zeolites can be used as support for
catalyst preparation. For example, HZSM-5 catalysts can be prepared
by incipient wetness impregnation method. Various metals can be
used for the catalyst preparation, such as Pt, Pd, Sn, Re, Rh, Ru,
Bi, Ba, Ti, Ni, and combinations thereof. The catalyst prepared
could be a mono-metallic catalyst, bi-metallic catalyst, or
tri-metallic catalyst. In some embodiments, the catalyst can be
prepared by an incipient wetness impregnation method using the
desired salt solution. After impregnation, the zeolite-metal
catalyst samples can be dried at room temperature, followed by oven
drying. Finally, the catalysts can be calcined under air, for
example, at 500.degree. C.
[0417] Mono-metallic catalysts include one metal such as Pt, Pd,
Sn, Re, Rh, Ru, Bi, Ba, Ti, Ni in a support, such as an
alumina-based support, zeolite-based support, or acidified alumina
based support. The mono-metallic catalysts used in these processes
may contain about 0.1% to about 1% (w/w), about 1% to about 5%
(w/w), about 5% to about 10% (w/w), about 10% to about 20% (w/w),
about 20% to about 30% (w/w), about 30% to about 40% (w/w), about
40% to about 50% (w/w), about 50% to about 60% (w/w), about 60% to
about 70% (w/w), about 70% to about 80% (w/w), about 80% to about
90% (w/w), or greater than 90% (w/w) of the metal, or in a range
bounded by any numerical value stated herein above. In some
preferred embodiments, the catalysts may contain about 0.05% to
about 0.075&, about 0.075% to about 0.1%, about 0.1% to about
1%, about 1% to about 2%, and about 2% to about 5% of the metal, or
in a range bounded by any numerical value stated herein above.
Examples of such mono-metallic catalysts include 0.5% Ru/ZSM-5, 1%
Ru/ZSM-5, 1.5% Ru/ZSM-5, 0.5% Pd/ZSM-5, 1% Pd/ZSM-5, 1.5% Pd/ZSM-5,
0.5% Pt/ZSM-5, 1% Pt/ZSM-5, 1.5% Pt/ZSM-5, 0.5% Pt/10%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pt/5%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 1% Pt/10%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pt/5%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 1% Pd/10%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pd/5%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 1% Pd/10%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pd/5%
H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pt/5.0%
H.sub.3BO.sub.3-Al.sub.2O.sub.3, 0.5% Pd/5.0%
H.sub.3BO.sub.3-Al.sub.2O.sub.3, 0.5% Ru/5.0%
H.sub.3BO.sub.3-Al.sub.2O.sub.3, 1% Pt/5.0%
H.sub.3BO.sub.3-Al.sub.2O.sub.3, 1% Pd/5.0%
H.sub.3BO.sub.3--Al.sub.2O.sub.3, and 1% Ru/5.0%
H.sub.3BO.sub.3--Al.sub.2O.sub.3.
[0418] Bi-metallic catalysts include a combination of two metals
selected from metals such Pt, Pd, Sn, Re, Rh, Ru, Bi, Ba, Ti, Ni in
supports such an alumina-based support, zeolite-based support, or
acidified alumina based support. The bi-metallic catalysts used in
these processes may contain two metals wherein each metal may be
present in about 0.1% to about 1% (w/w), about 1% to about 5%
(w/w), about 5% to about 10% (w/w), about 10% to about 20% (w/w),
about 20% to about 30% (w/w), about 30% to about 40% (w/w), about
40% to about 50% (w/w), about 50% to about 60% (w/w), about 60% to
about 70% (w/w), about 70% to about 80% (w/w), about 80% to about
90% (w/w), or greater than 90% (w/w), in any possible combination
with the other metal, and in a range bounded by any numerical value
stated herein above. or in a range bounded by any numerical value
stated herein above. Examples of such bi-metallic catalysts include
0.5% Pt-0.5% Sn/Al.sub.2O.sub.3, 0.5% Pd-0.5% Sn/Al.sub.2O.sub.3,
0.5% Pt-0.75% Sn/Al.sub.2O.sub.3, 0.5% Pd-0.75% Sn/Al.sub.2O.sub.3,
0.5% Pt-1% Sn/Al.sub.2O.sub.3, 0.5% Pd-1% Sn/Al.sub.2O.sub.3, 0.5%
Pt-0.5% Bi/Al.sub.2O.sub.3, 0.5% Pd-0.5% Bi/Al.sub.2O.sub.3, 0.5%
Pt-0.75% Bi/Al.sub.2O.sub.3, 0.5% Pd-0.75% Bi/Al.sub.2O.sub.3, 0.5%
Pt-1% Bi/Al.sub.2O.sub.3, 0.5% Pd-1% Bi/Al.sub.2O.sub.3, 0.5%
Pt-0.5% Ba/Al.sub.2O.sub.3, 0.5% Pd-0.5% Ba/Al.sub.2O.sub.3, 0.5%
Pt-0.75% Ba/Al.sub.2O.sub.3, 0.5% Pd-0.75% Ba/Al.sub.2O.sub.3, 0.5%
Pt-1% Ba/Al.sub.2O.sub.3, and 0.5% Pd-1% Ba/Al.sub.2O.sub.3.
[0419] Tri-metallic catalysts include a combination of three metals
selected from metals such Pt, Pd, Sn, Re, Rh, Ru, Bi, Ba, Ti, Ni in
supports such as an alumina-based support, zeolite-based support,
or acidified alumina based support. The tri-metallic catalysts used
in these processes may contain three metals wherein each metal may
be present in about 0.1% to about 1% (w/w), about 1% to about 5%
(w/w), about 5% to about 10% (w/w), about 10% to about 20% (w/w),
about 20% to about 30% (w/w), about 30% to about 40% (w/w), about
40% to about 50% (w/w), about 50% to about 60% (w/w), about 60% to
about 70% (w/w), about 70% to about 80% (w/w), about 80% to about
90% (w/w), or greater than 90% (w/w), in any possible combination
with the other two metals, and in a range bounded by any numerical
value stated herein above. or in a range bounded by any numerical
value stated herein above. Examples of such tri-metallic catalysts
include 0.5% Pt-0.5% Sn-0.5% Bi/Al.sub.2O.sub.3, 0.5% Pt-0.5%
Sn-0.75% Bi/Al.sub.2O.sub.3, 0.75% Pt-0.5% Sn-0.75%
Bi/Al.sub.2O.sub.3, 0.5% Pd-0.5% Sn-0.5% Bi/Al.sub.2O.sub.3, 0.5%
Pt-0.5% Sn-0.5% Ba/Al.sub.2O.sub.3, 0.5% Pt-0.5% Sn-0.75%
Ba/Al.sub.2O.sub.3, 0.75% Pt-0.5% Sn-0.75% Ba/Al.sub.2O.sub.3, 0.5%
Pd-0.5% Sn-0.5% Ba/Al.sub.2O.sub.3.
[0420] The general reaction conditions under which the feedstock
containing ethanol can be converted to hydrocarbons in a catalytic
reactor includes temperature in the range of 300-400.degree. C.,
pressure in the range of 20-50 atm, gas flow (e.g., N.sub.2) at the
rate of 1.5-6 h.sup.-1 and Liquid Hourly Space Velocity (LHSV) of
2-4 h.sup.-1. The specific catalyst compositions for each reaction,
and the reaction conditions are recited in the descriptions of the
FIGS. 18A-23C, with corresponding product distribution shown in the
respective figures. As discussed in this application, these
reaction conditions can be appropriately adjusted to achieve a
desired reaction product composition.
[0421] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains hydrocarbons of average
carbon number of about 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, or 22. In some embodiments, the hydrocarbon mixture
produced from the above-described processes contains hydrocarbons
of average carbon number of about 6, 7, 8, 9, or 10.
[0422] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains about 0.1% to about 1%
(w/w), about 1% to about 5% (w/w), about 5% to about 10% (w/w),
about 10% to about 20% (w/w), about 20% to about 30% (w/w), about
30% to about 40% (w/w), about 40% to about 50% (w/w), about 50% to
about 60% (w/w), about 60% to about 70% (w/w), about 70% to about
80% (w/w), about 80% to about 90% (w/w), or greater than 90% (w/w)
aromatics, or in a range bounded by any numerical value stated
herein above.
[0423] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains about 0.1% to about 1%
(w/w), about 1% to about 5% (w/w), about 5% to about 10% (w/w),
about 10% to about 20% (w/w), about 20% to about 30% (w/w), about
30% to about 40% (w/w), about 40% to about 50% (w/w), about 50% to
about 60% (w/w), about 60% to about 70% (w/w), about 70% to about
80% (w/w), about 80% to about 90% (w/w), or greater than 90% (w/w)
alkenes, or in a range bounded by any numerical value stated herein
above.
[0424] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains about 0.1% to about 1%
(w/w), about 1% to about 5% (w/w), about 5% to about 10% (w/w),
about 10% to about 20% (w/w), about 20% to about 30% (w/w), about
30% to about 40% (w/w), about 40% to about 50% (w/w), about 50% to
about 60% (w/w), about 60% to about 70% (w/w), about 70% to about
80% (w/w), about 80% to about 90% (w/w), or greater than 90% (w/w)
alkanes, or in a range bounded by any numerical value stated herein
above.
[0425] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains less than about 0.01% (w/w),
less than about 0.1% (w/w), less than about 1% (w/w), less than
about 5% (w/w), less than about 10% (w/w), less than about 20%
(w/w), or less than about 30% (w/w) of oxygenates. As used herein,
the term "oxygenates" is defined to include oxygen containing
organic compounds such as alcohols, ethers, carbonyl compounds
(aldehydes, ketones, carboxylic acids, carbonates, and the like).
Representative oxygenates include, but are not necessarily limited
to, lower straight chain or branched aliphatic alcohols, their
unsaturated counterparts. Examples include but are not necessarily
limited to: methanol; ethanol; n-propanol; isopropanol; C4-C10
alcohols; methyl ethyl ether; dimethyl ether; diethyl ether;
di-isopropyl ether; methyl mercaptan; methyl formate, methyl
acetate, formaldehyde; di-methyl carbonate; trimethyl orthoformate,
and dimethyl ketone.
[0426] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains greater than about 10%
(w/w), greater than about 20% (w/w), greater than about 30% (w/w),
greater than about 40% (w/w), greater than about 50% (w/w), greater
than about 60% (w/w), greater than about 70% (w/w), greater than
about 80% (w/w), or greater than about 90% (w/w) of liquid
hydrocarbon at standard temperature and pressure.
[0427] In some embodiments, the hydrocarbon mixture produced from
the above-described processes contains less than about 0.01% (w/w),
less than about 0.1% (w/w), less than about 1% (w/w), less than
about 5% (w/w), less than about 10% (w/w), less than about 20%
(w/w), or less than about 30% (w/w) of gaseous hydrocarbon at
standard temperature and pressure.
[0428] In some embodiments, commercially available reforming
catalysts can be used in the practice of the invention that are
available from manufacturers such as Tanaka Kikinzoju Group, Holder
Topsoe, UOP, Axens, Johnson Matthey, Criterion, Sud-Chemie,
Albermarle, Grace Davison, BASF, ExxonMobil Chemical, and JSC
Angarsk.
[0429] In one embodiment, the reforming catalysts used in the
methods described herein can include Ru/Al.sub.2O.sub.3 produced by
Tanaka such as TRC10-2A and TRC10-1A. The reforming catalysts may
also be chosen from Johnson Matthey's KATALCO.sub.JM.TM. catalysts
such as the KATALCO.sub.JM.TM. 23-series, 57-series, 25-series and
46-series catalysts. Examples of reforming catalysts that may be
obtained from UOP include CCR Platforming Catalysts (eg., R-134,
R-234, R-254, R-262, R-264, R-274, R-284), Semi-Regenerative
Platforming Catalysts (eg., R-56, R-86, R-98, R-500), Cyclic
Reforming Catalysts (eg., R-85, R-88), Naphtha Hydrotreating
Catalysts (S-120, S-125),
[0430] In some embodiments, catalysts produced by JSC Angarsk may
also be used in the processes described herein. Such catalysts may
include reforming catalysts (eg., RB-35YuKA, RB-33U, RB-44U, PR-81,
PR-71, APM-99, AP-56, and AP-64), isomerization catalysts (eg.,
SI-1, SI-2, IP-82, IP-62M, and KI-16M), hydrogenation catalysts
(eg., APU, APKB, APKGS, APKGU, GIPH-108, PALLADIUM CHARCOAL, PU-A,
PKA-25 PALLADIUM SIBUNITE, PALLADIUM ON ACTIVE ALLUMINIUM OXIDE IN
SULFURATED FORM, NVS-A, AP-15, AP-10), hydrotreating catalysts
(eg., GO-38A, GO-15, AGKD-400, and A-GPV), oxidation catalysts
(eg., KO-10), hydrocracking catalysts (eg., SGK-1, SGK-5, GI-03M,
GKM-21M, and KDM-10), methanation catalysts (eg., ANKM), conversion
catalysts (eg., GIAP-8, AKN-M, STK-05, and GIAP-3-6N), adsorbents
catalysts (eg., MOA-98, A-09-MOA, PS-17, PS-17 M, AGS-60, PS-2003,
AR-25, and APS), and protective bed catalysts (eg., FOR-1,
FOR-2).
[0431] In one embodiment, the reforming catalyst may be mixed with
a gas-to-liquid catalyst to convert gaseous mixtures to liquid
hydrocarbon. In one embodiment of a gas-to-liquid conversion
process, synthesis gas, a mixture of hydrogen and carbon monoxide,
generated during the processing of the biomass is purified to
remove impurities and converted into liquid hydrocarbons using a
gas to liquid catalyst. In another embodiment, a gas to liquid
catalyst can be used to convert low molecular weight hydrocarbons
such as propane or butane that can form in the catalytic conversion
process into higher molecular weight hydrocarbons. Examples of
gas-to-liquid catalysts that can be used include cobalt-based
synthesis catalysts developed by Criterion, and Fischer-Tropsch
catalysts and modifications thereof. The gas to liquid catalyst can
be in the same bed as the reforming catalyst or the light gases can
be collected and directed to another reactor for further treatment
of the gases.
[0432] In one embodiment, the reforming catalyst can be combined
with one or more catalysts such as gas-to-liquid catalysts. For
example, a combination of reforming catalyst and gas-to-liquid
catalyst may be used in a catalytic reactor to convert processed
biomass or biomass-derived products into constituents of fuel such
as gasoline, diesel, kerosene, jet fuel and aviation fuel. FIG. 8A,
for example, provides a schematic diagram of the longitudinal
section of a reactor (eg., a trickle-bed reactor), in which a
catalytic conversion of biomass-derived building blocks takes place
in the presence of two catalysts. This diagram depicts an example
where two catalysts, Catalyst 1 and Catalyst 2, are in separate
layers. The flow of gas and liquid constituents is shown by the
arrows entering and leaving the catalytic reactor. Another
embodiment is depicted by FIG. 8B, which also provides a schematic
diagram of the longitudinal section of another reactor (eg., a
trickle-bed reactor), in which catalytic conversion of
biomass-derived building blocks takes place in the presence of two
catalysts. This diagram depicts an example where two catalysts,
Catalyst 1 and Catalyst 2 are blended together. The flow of gas and
liquid constituents is shown by the arrows entering and leaving the
catalytic reactor. FIG. 8C provides a schematic diagram of another
embodiment, in which two reactors are connected in a pipeline such
that products and/or unreacted constituents from the first reactor
are directed into the second reactor for further catalytic
conversion. The catalyst bed in the first reactor is denoted by
Catalyst 1 and that in the second reactor is denoted by Catalyst 2.
Various combinations of Catalyst 1 and Catalyst 2 may be used. For
example, in one embodiment, Catalyst 1 can be a dehydration
catalyst and Catalyst 2 can be an oligomerization catalyst. In
another embodiment, Catalyst 1 can be a dehydration catalyst and
Catalyst 2 can be a hydrogenation catalyst. In one embodiment,
Catalyst 1 can be a dehydration catalyst and Catalyst 2 can be a
C--H bond activating catalysts. In some embodiments, Catalyst 1 and
Catalyst 2 may be same, while in some embodiments, they may be
different. In some embodiments, Catalyst 2 is a hydrogenation
catalyst selected from the group consisting of Raney/Ni, Rh
catalysts, Re catalyts, Pt catalysts, Ru catalysts, Lindlar's
catalyst, and various transition metal catalysts. If the catalysts
are same, then the two reactors may be operating under different
conditions such as temperature, pressure, flow-rates, and running
time.
[0433] In some embodiments, two or more catalytic reactors may be
arranged in a manner such that products and/or unreacted
constituents from one or more of the catalytic reactors may be
directed to other reactors in the system. Various combinations of
catalysts may be used in these reactors, including a dehydration
catalyst, an oligomerization catalyst, a hydrogenation, a C--H bond
activating catalysts, a reforming catalyst, and mixtures thereof.
In some embodiments, the two or more reactors may be operating
under different conditions such as temperature, pressure,
flow-rates, and running time.
[0434] Similar mixed catalyst arrangements can be used with other
catalyst combinations.
[0435] In other embodiments, catalysts or subsequent processing
steps can be included to reduce the molecular weight of at least
one component of the catalyst process. In this stage, a liquid is
formed which looks and feels like wax at room temperature. The high
molecular weight components and be separated and in a subsequent
process, a cracking and isomerization step can occur, which
"tailors" the molecule chains into products with desired
properties. This yields high-quality liquids such as diesel,
kerosene and lubricant oil.
[0436] The catalytic processes described herein may also be
performed in the presence of solid supports. A catalyst support is
a material, usually a solid with a high surface area, to which a
catalyst is affixed. While it is generally considered to be inert
and mainly considered to be useful in providing high surface area,
in many cases the supports can facilitate the catalysis by
providing appropriate conditions. For example, solid supports may
provide acidic sites for dehydration and basic sites for
retro-aldol reaction. The choice of a particular support depends on
the nature of application and reaction conditions. The preparation
steps and the quality of the raw materials strongly affect the
support properties. Examples of supports include alumina, silica,
magnesia, zirconia, zeolites, and polymeric resins (such as
polystyrene-divinyl benzene, Nafion, poly(vinylpyridinium
dichromate)).
[0437] Acidity and basicity of a catalyst support may play a role
in the catalytic performance. A variety of methods can be used to
characterize the acidity of solid supports. For example, in some
embodiments, an indicator may be used to measure the acidity of the
solid catalysts. An indicator is usually a neutral organic base,
which upon absorption on the solid is changed to its conjugated
acid form. The neutral base form of the indicator has a different
color than the conjugated acid form. Examples of neutral base
indicators include neutral red, methyl red, phenylazonaphthylamine,
p-dimethylaminobenzene, 2-amino-5-azotoluene,
benzeneazodephenylamine, 4-dimethylaminoazo-1-naphthalene, crystal
violet, p-nitrobenzeneazo-(p'-nitro) diphenylamine,
dicinnamalacetone, benzalacetophenone, and anthraquinone. Acid
strength can also be measured by gaseous base absorption methods.
In this method, the amount of gaseous base that a solid acid can
absorb chemically from the gaseous phase is used as a measure of
the number of acidic sites on its surface. Examples of bases that
can be used include ammonia, pyridine, n-butylamine, and
isopropylamine. In another method, called the .alpha. test, the
catalytic activity of the solid catalyst is used to measure the
acidity. The test uses n-hexane as the probe molecule, and the
.alpha. value of a catalyst is defined as the ratio of the
first-order rate constant for n-hexane cracking over the sample to
that obtained over an arbitrary standard, measured at 538.degree.
C. Other methods such as microcalorimetric methods, conductometric
titration, UV-Visible spectroscopy, aromatics absorption, NMR,
luminescence, electron spin resonance, and other spectrophotometric
methods may also be used to determine the acidity and basicity of
the solid support. Catalytic characteristics can be evaluated using
other methods, such as BET, temperature programmed desorption of
ammonia (NH3-TPD) and carbon dioxide (CO.sub.2-TPD), FTIR
spectroscopy and XRD.
[0438] In one embodiment, an automated chemisorption analysis
instrument is used to characterize the catalyst. For example,
AMI-300, an automated chemisorption analysis instrument offered by
Altamira Instruments may be used to characterize the catalyst.
AMI-300 is capable of performing the major dynamic techniques
required for fully characterizing a catalyst, using dynamic
procedures such as temperature programmed desorption (TPD),
temperature programmed reduction/oxidation (TPR/O), temperature
programmed reaction (TPRx), pulse chemisorption, catalyst
treatment, dynamic BET surface area and pulse calibration. The
AMI-300 is a fully automated catalyst characterization instrument
which uses proprietary software to switch gas streams, control gas
flow rates, blend gases, control temperatures, control ramp rates,
and to collect all the data needed to quantify the adsorption and
desorption of gas molecules on the surface of a catalyst. The
AMI-300 comes standard with a highly linear thermal conductivity
detector (TCD). In addition to the TCD, AMI instruments may be
equipped with a wide range of auxiliary detection devices such as
Mass Spectrometer, Flame Ionization Detector, Flame Photometric
Detector, Gas Chromatograph and FTIR.
[0439] A number of methods may be used to prepare supported
catalysts. In the impregnation method, a suspension of the solid
support is treated with a solution of a precatalyst, and the
resulting material is then activated under conditions that will
convert the precatalyst (often a metal salt) to a more active
state. In such cases, the catalyst support is usually in the form
of pellets. For example, a solid support such as alumina or silica
may be treated with a solution of metal nitrates or metal halides.
The catalyst can then be dried and calcined to drive off the
volatile components within the solution, depositing the metal salt
on the solid support. The maximum loading is limited by the
solubility of the precursor in the solution. In some embodiments,
the calcination step involves the conversion of the dispersed metal
salt solution into an oxide by heating at a high temperature in the
presence of air or oxygen. Finally, the metal oxide may be reduced
to the metallic state by reducing conditions such as by passing a
stream of hydrogen to give the final metal/support catalyst. Other
gases such as hydrogen sulfide, ammonia, and carbon monoxide may
also be used to reduce the metal oxide. The calcination and the
reduction steps are often referred to as the activation steps in
this process. In some embodiments, the above steps are repeated
till the desired results are achieved.
[0440] Although direct reduction of many precursors can lead to
well-dispersed catalysts, direct reduction is often highly
exothermic and can lead to mixed metal-support phases. Moreover, it
can produce a pyrophoric catalyst that needs to be passivated,
often making it impractical for use on an industrial scale.
Therefore, a calcination procedure is usually performed to form the
pure metal oxide particles before further treatment such as
reduction. Both the heating rate and air flow during calcination
have been shown to be highly important in influencing the property
of the final catalyst.
[0441] A number of impregnation methods can be used in the
processes described herein, such as wet impregnation (WI), whereby
an excess amount of solution is used, and pore volume impregnation
(PVI), in which an amount to just fill the pore volume of the
support is used. The latter method is also known as incipient
wetness impregnation (IWI) or dry impregnation (DI), because the
impregnated material keeps a dry character at a macroscopic
scale.
[0442] In one embodiment, the catalytic system is prepared using
amorphous silica-alumina (ASA) supports in combination with USY and
.beta.-zeolites. These supports are ASA, SIRAL 40 (from Condea GmbH
Germany), USY zeolite (from Toso Chemical Company, Japan) and
.beta.-zeolite (from Sud-Chemie). Alumina-based Cataloid AP-1 (from
Catalyst and Chemical Industry, Japan) is used as a binder to
prepare extrudates. Cataloid AP-I comprises 71 wt. % alumina, 11
wt. % acetic acid and 18 wt. % water and it has an average particle
size of 54 .mu.m. The supports selected are first weighed and then
mixed with a weighed amount of AP-1 and formed into 1/32 in.
extrudates. This procedure is started with the weighing of the
supports, Cataloid AP-I and water in predetermined quantities and
then mixing them together. The mixture is agitated strongly to
change it to hard paste. The paste is put into the syringe barrel
and pressed to form extrudates which are collected on a filter
paper tray. The extrudates are dried in an oven maintained at
120.degree. C. for 2h and then broken into small 3-4 mm pieces,
sieved and calcined in a quartz tube calcination setup provided
with air flow. The extrudates are housed between the glass wool in
the quartz tube and fixed in the heating furnace and connected to
an airflow of 250 ml/min. The temperature is raised to 120.degree.
C. and maintained for 30 min. Then the temperature is increased to
550.degree. C. and maintained at this temperature for 2 h. Then the
heating is stopped, the furnace is opened and the extrudates are
allowed to cool to ambient temperature while the air is flowing to
provide rapid cooling. The extrudates are then removed from the
quartz tube and sieved to remove any powder present. Then the
extrudates are weighed to record the weight of extrudates
formed.
[0443] The extrudates are impregnated with metals pairs Ni--W or
Ni--Mo using co-impregnation technique, the metal loading of NiO 4
wt. % and WO.sub.3 15 wt. %, or MoO.sub.3 15 wt. %. Two types of
solutions are prepared: one containing Ni and W while the other has
Ni and Mo. The solutions are prepared using deionized water. The
metal salts used are nickel nitrate hexahydrate
[Ni(NO.sub.3).sub.2.6H.sub.2O], ammonium metatungstate pentahydrate
[(NH.sub.4).sub.6W.sub.12O.sub.39.5H.sub.2O] and ammonium molybdate
tetrahydrate [(NH.sub.4).sub.6Mo.sub.7O.sub.24.4H.sub.2O]. In case
of NiMo solution, the ammonium molybdate tetrahydrate is added
first in water and dissolved completely. Then the predetermined
quantity of nickel nitrate is added; the mixture is stirred
quickly, and the solution is used within 1-2 min before the
solution gets turbid due to complex formation. The metals are
impregnated on a batch of 10 g of extrudates in a wide-mouthed
crucible. The solutions are added dropwise till all the extrudates
are completely wet. The extrudates are then allowed to adsorb the
metals for 2h. Then the extrudates are placed in an oven maintained
at 120.degree. C. under a reduced pressure of 410 mmHg pressure for
2 h. The purpose of drying under vacuum is to segregate and bring
the Mo ions onto the surface of the catalysts and convert them into
MoO.sub.3 and thus to provide high hydrogenation activity on the
surface of the catalyst. At the end of the drying process, the
extrudates are placed in a temperature-programmed furnace for
calcination. The calcination is conducted under the following
heating program: The temperature is raised to 120.degree. C. and
maintained for 2 h, then the temperature is raised to 550.degree.
C. at a heating rate of 2.degree. C./min and maintained for 2h at
this temperature. Then the furnace is allowed to cool overnight.
The samples are kept in airtight glass bottles for characterization
and catalytic evaluation. The weights of the finished catalysts
obtained after calcination are in the range 12.6-13.0 g per
batch.
[0444] Alternatively, supported catalysts can be prepared from
homogeneous solution by co-precipitation. In co-precipitation,
salts of the active metal and support are dissolved and mixed such
that nucleation and growth of a combined solid precursor of the
active metal and support is obtained in a single step. Very high
metal loadings of 70 wt. % and higher can be achieved while
maintaining small particle sizes, and as such, it is a convenient
way to produce catalysts with a high metal weight to volume ratio.
For example, an acidic solution of aluminum salts and precatalyst
can be treated with base to precipitate the mixed hydroxide, which
is subsequently calcined. Co-precipitation can be utilized to
produce catalysts such as nickel alumina for steam reforming, iron
copper potassium for Fischer-Tropsch synthesis, and
Cu/ZnO/Al.sub.2O.sub.3 catalysts for methanol synthesis.
[0445] In some embodiments, the catalysts have a surface area of
about 1 m.sup.2/g, about 10 m.sup.2/g, about 20 m.sup.2/g, about 30
m.sup.2/g, about 40 m.sup.2/g, about 50 m.sup.2/g, about 60
m.sup.2/g, about 70 m.sup.2/g, about 80 m.sup.2/g, about 100
m.sup.2/g, about 110 m.sup.2/g, about 120 m.sup.2/g, about 130
m.sup.2/g, about 140 m.sup.2/g, about 150 m.sup.2/g, about 160
m.sup.2/g, about 170 m.sup.2/g, about 180 m.sup.2/g, about 190
m.sup.2/g, about 200 m.sup.2/g, about 210 m.sup.2/g, about 220
m.sup.2/g, about 230 m.sup.2/g, about 240 m.sup.2/g, about 250
m.sup.2/g, about 260 m.sup.2/g, about 270 m.sup.2/g, about 280
m.sup.2/g, about 290 m.sup.2/g, about 300 m.sup.2/g, about 310
m.sup.2/g, about 320 m.sup.2/g, about 330 m.sup.2/g, about 340
m.sup.2/g, about 350 m.sup.2/g, about 360 m.sup.2/g, about 370
m.sup.2/g, about 380 m.sup.2/g, about 390 m.sup.2/g, about 400
m.sup.2/g, about 410 m.sup.2/g, about 410 m.sup.2/g, about 410
m.sup.2/g, about 420 m.sup.2/g, about 430 m.sup.2/g, about 440
m.sup.2/g, about 450 m.sup.2/g, about 460 m.sup.2/g, about 470
m.sup.2/g, about 480 m.sup.2/g, about 500 m.sup.2/g, about 550
m.sup.2/g, about 600 m.sup.2/g, about 650 m.sup.2/g, about 700
m.sup.2/g, about 750 m.sup.2/g, about 800 m.sup.2/g, about 850
m.sup.2/g, about 900 m.sup.2/g, about 950 m.sup.2/g, and about 1000
m.sup.2/g.
[0446] In some embodiments, the catalyst may have a pore volume of
about 0.01 cm.sup.3/g, about 0.02 cm.sup.3/g, about 0.03
cm.sup.3/g, about 0.04 cm.sup.3/g, about 0.05 cm.sup.3/g, about
0.06 cm.sup.3/g, about 0.07 cm.sup.3/g, about 0.08 cm.sup.3/g,
about 0.09 cm.sup.3/g, about 0.1 cm.sup.3/g, about 0.2 cm.sup.3/g,
about 0.3 cm.sup.3/g, about 0.4 cm.sup.3/g, about 0.5 cm.sup.3/g,
about 0.6 cm.sup.3/g, about 0.7 cm.sup.3/g, about 0.8 cm.sup.3/g,
about 0.9 cm.sup.3/g, about 1.0 cm.sup.3/g, about 1.1 cm.sup.3/g,
about 1.2 cm.sup.3/g, about 1.3 cm.sup.3/g, about 1.4 cm.sup.3/g,
about 1.5 cm.sup.3/g, about 1.6 cm.sup.3/g, about 1.7 cm.sup.3/g,
about 1.8 cm.sup.3/g, about 1.9 cm.sup.3/g, about 2.0 cm.sup.3/g,
about 2.1 cm.sup.3/g, about 2.2 cm.sup.3/g, about 2.3 cm.sup.3/g,
about 2.4 cm.sup.3/g, about 2.5 cm.sup.3/g, about 2.6 cm.sup.3/g,
about 2.7 cm.sup.3/g, about 2.8 cm.sup.3/g, about 2.9 cm.sup.3/g,
about 3.0 cm.sup.3/g, about 3.1 cm.sup.3/g, about 3.2 cm.sup.3/g,
about 3.3 cm.sup.3/g, about 3.4 cm.sup.3/g, about 3.5 cm.sup.3/g,
about 3.6 cm.sup.3/g, about 3.7 cm.sup.3/g, about 3.8 cm.sup.3/g,
about 3.9 cm.sup.3/g, about 4.0 cm.sup.3/g, about 4.1 cm.sup.3/g,
about 4.2 cm.sup.3/g, about 4.3 cm.sup.3/g, about 4.4 cm.sup.3/g,
about 4.5 cm.sup.3/g, about 4.6 cm.sup.3/g, about 4.7 cm.sup.3/g,
about 4.8 cm.sup.3/g, about 4.9 cm.sup.3/g, about 5.0 cm.sup.3/g,
about 5.1 cm.sup.3/g, about 5.2 cm.sup.3/g, about 5.3 cm.sup.3/g,
about 5.4 cm.sup.3/g, about 5.5 cm.sup.3/g, about 5.6 cm.sup.3/g,
about 5.7 cm.sup.3/g, about 5.8 cm.sup.3/g, about 5.9 cm.sup.3/g,
about 6.0 cm.sup.3/g, about 7.0 cm.sup.3/g, about 8.0 cm.sup.3/g,
about 9.0 cm.sup.3/g, and about 10.0 cm.sup.3/g.
[0447] In some embodiments, the average pore size of the catalyst
can be about 0.1 .ANG., about 0.2 .ANG., about 0.3 .ANG., about 0.4
.ANG., about 0.5 .ANG., about 0.6 .ANG., about 0.7 .ANG., about 0.8
.ANG., about 0.9 .ANG., about 1.0 .ANG., about 2.0 .ANG., about 3.0
.ANG., about 4.0 .ANG., about 5.0 .ANG., about 6.0 .ANG., about 7.0
.ANG., about 8.0 .ANG., about 9.0 .ANG., about 10.0 .ANG., about
20.0 .ANG., about 25.0 .ANG., about 30.0 .ANG., about 35.0 .ANG.,
about 40.0 .ANG., about 45.0 .ANG., about 50.0 .ANG., about 55.0
.ANG., about 60.0 .ANG., about 65.0 .ANG., about 70.0 .ANG., about
75.0 .ANG., about 80.0 .ANG., about 85.0 .ANG., about 90.0 .ANG.,
about 95.0 .ANG., and about 100.0 .ANG..
[0448] In some embodiments, the pressure drop across the catalytic
column may be about 1%, about 2%, about 3%, about 4%, about 5%,
about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about
12%, about 13%, about 14%, about 15%, about 16%, about 17%, about
18%, about 19%, about 20%, about 21%, about 22%, about 23%, about
24%, about 25%, about 26%, about 27%, about 28%, about 29%, about
30%, about 31%, about 32%, about 33%, about 34%, about 35%, about
36%, about 37%, about 38%, about 39%, about 40%, about 41%, about
42%, about 43%, about 44%, about 45%, about 46%, about 47%, about
48%, about 49%, and about 50%.
[0449] In some embodiments, the amount of active metal catalyst
loading in the catalyst bed can be about 1 wt. %, about 2 wt. %,
about 3 wt. %, about 4 wt. %, about 5 wt. %, about 6 wt. %, about 7
wt. %, about 8 wt. %, about 9 wt. %, about 10 wt. %, about 15 wt.
%, about 20 wt. %, about 25 wt. %, about 30 wt. %, about 35 wt. %,
about 40 wt. %, about 45 wt. %, about 50 wt. %, about 55 wt. %,
about 60 wt. %, about 65 wt. %, about 70 wt. %, about 80 wt. %,
about 90 wt. %, about 95 wt. %, and about 100 wt. %.
[0450] In some embodiments, the gas flow rate in the reactor is
about 1 ml/min, about 2 ml/min, about 3 ml/min, about 4 ml/min,
about 5 ml/min, about 6 ml/min, about 7 ml/min, about 8 ml/min,
about 9 ml/min, about 10 ml/min, about 20 ml/min, about 30 ml/min,
about 40 ml/min, about 50 ml/min, about 60 ml/min, about 70 ml/min,
about 80 ml/min, about 90 ml/min, about 100 ml/min, about 150
ml/min, about 200 ml/min, about 250 ml/min, about 300 ml/min, about
350 ml/min, about 400 ml/min, about 450 ml/min, about 500 ml/min,
about 550 ml/min, about 600 ml/min, about 650 ml/min, about 700
ml/min, about 750 ml/min, about 800 ml/min, about 850 ml/min, about
900 ml/min, about 950 ml/min, and about 1000 ml/min.
[0451] In some embodiments, the liquid flow rate in the reactor is
about 1 ml/min, about 2 ml/min, about 3 ml/min, about 4 ml/min,
about 5 ml/min, about 6 ml/min, about 7 ml/min, about 8 ml/min,
about 9 ml/min, about 10 ml/min, about 20 ml/min, about 30 ml/min,
about 40 ml/min, about 50 ml/min, about 60 ml/min, about 70 ml/min,
about 80 ml/min, about 90 ml/min, about 100 ml/min, about 150
ml/min, about 200 ml/min, about 250 ml/min, about 300 ml/min, about
350 ml/min, about 400 ml/min, about 450 ml/min, about 500 ml/min,
about 550 ml/min, about 600 ml/min, about 650 ml/min, about 700
ml/min, about 750 ml/min, about 800 ml/min, about 850 ml/min, about
900 ml/min, about 950 ml/min, and about 1000 ml/min.
[0452] In some embodiments, product selectivity, product
distribution and poisoning of the catalysts is impacted by the
operating pressure of the gases that contact the catalyst.
[0453] In some embodiments, the pressure within a reactor can vary
from a low-pressure zone to a high pressure zone, and vice-versa.
In some embodiments, a reactor may contain a combination of various
pressure zones. In some embodiments, there is a difference in
pressure between two or more reactors within the system. In some
embodiments, the pressure can change by 2-fold, 3-fold, 5-fold,
10-fold, 20-fold, 30-fold, 40-fold, 50-fold, 100-fold, or any range
described hereinabove. The operating pressure, for example, may
vary from 10 psi to 50 psi. The operating pressure can be anywhere
in the range of about 0.1 psi, 1 psi, 5 psi, 10 psi, 20 psi, 30
psi, 40 psi, 50 psi, 60 psi, 70 psi, 80 psi, 90 psi, 100 psi, 200
psi, 300 psi, 400 psi, 500 psi, 1000 psi, or bound by any numerical
value stated herein above.
[0454] In some embodiments, product selectivity, product
distribution and poisoning of the catalysts is impacted by the
operating temperature of the reactor. In some embodiments, the
temperature within a reactor can vary from a low temperature zone
to a high temperature zone, and vice-versa. In some embodiments, a
reactor may contain a combination of various temperature zones. In
some embodiments, there is a difference in temperature between two
or more reactors within the system. In some embodiments, there is a
difference in pressure between two or more reactors within the
system. In some embodiments, the temperature can change by 2-fold,
3-fold, 5-fold, 10-fold, 20-fold, 30-fold, 40-fold, 50-fold,
100-fold, or any range described hereinabove. The operating
temperature, for example, may vary from 10.degree. C. to 50.degree.
C. The operating temperature can be anywhere in the range of about
50.degree. C., 60.degree. C., 70.degree. C., 80.degree. C.,
90.degree. C., 100.degree. C., 200.degree. C., 300.degree. C.,
400.degree. C., 500.degree. C., 1000.degree. C., or bound by any
numerical value stated herein above.
[0455] In some embodiments, product selectivity, product
distribution and poisoning of the catalysts is impacted by the
flow-rate of fluids within a reactor. In some embodiments, the
flow-rate within a reactor can vary from a low flow-rate zone to a
high flow-rate zone, and vice-versa. In some embodiments, a reactor
may contain a combination of various flow-rate zones. In some
embodiments, there is a difference in flow-rates between two or
more reactors within the system. In some embodiments, there is a
difference in flow-rate between two or more reactors within the
system. In some embodiments, the flow-rate can change by 2-fold,
3-fold, 5-fold, 10-fold, 20-fold, 30-fold, 40-fold, 50-fold,
100-fold, or any range described hereinabove. The flow-rates for
example, may vary from 5 ml/min to 50 ml/min. The flow-rates can be
about 1 ml/min, about 2 ml/min, about 3 ml/min, about 4 ml/min,
about 5 ml/min, about 6 ml/min, about 7 ml/min, about 8 ml/min,
about 9 ml/min, about 10 ml/min, about 20 ml/min, about 30 ml/min,
about 40 ml/min, about 50 ml/min, about 60 ml/min, about 70 ml/min,
about 80 ml/min, about 90 ml/min, about 100 ml/min, about 150
ml/min, about 200 ml/min, about 250 ml/min, about 300 ml/min, about
350 ml/min, about 400 ml/min, about 450 ml/min, about 500 ml/min,
about 550 ml/min, about 600 ml/min, about 650 ml/min, about 700
ml/min, about 750 ml/min, about 800 ml/min, about 850 ml/min, about
900 ml/min, about 950 ml/min, and about 1000 ml/min, or bound by
any numerical value stated herein above.
[0456] In some embodiments, product selectivity, product
distribution and poisoning of the catalysts is impacted by the
viscosity of the reaction mixture within a reactor. In some
embodiments, the viscosity within a reactor can vary from a low
viscosity zone to a high viscosity zone, and vice-versa. In some
embodiments, a reactor may contain a combination of various
viscosity zones. In some embodiments, there is a difference in
viscosities between two or more reactors within the system. In some
embodiments, there is a difference in viscosity between two or more
reactors within the system. In some embodiments, the viscosity can
change by 2-fold, 3-fold, 5-fold, 10-fold, 20-fold, 30-fold,
40-fold, 50-fold, 100-fold, or any range described hereinabove. The
viscosty for example, may vary from 5 cP to 50 cP. In some
embodiments, the viscosity of the reaction mixture in the reactor
may range from about 1 centipoise (cP) to about 5 Cp, about 5 cP to
about 10 cP, about 10 cP to about 15 cP, about 15 cP to about 20
cP, about 20 cP to about 25 cP, about 25 cP to about 30 cP, about
30 cP to about 35 cP, about 40 cP to about 45 cP, about 45 cP to
about 50 cP, about 50 cP to about 55 cP, about 55 cP to about 60
cP, about 60 cP to about 65 cP, about 65 cP to about 70 cP, about
70 cP to about 75 cP, about 75 cP to about 80 cP, about 80 cP to
about 85 cP, about 85 cP to about 90 cP, about 90 cP to about 95
cP, about 95 cP to about 100 cP, about 100 cP to about 200 cP,
about 200 cP to about 300 cP, about 300 cP to about 400 cP, about
400 cP to about 500 cP, about 500 cP to about 600 cP, about 600 cP
to about 700 cP, about 700 cP to about 800 cP, about 800 cP to
about 900 cP, about 900 cP to about 1000 cP, or in a range bounded
by any numerical value stated herein above.
[0457] In some embodiments, all or one of the above described
parameters, including temperature, pressure, viscosity and
flow-rate are optimized to increase yield and minimize catalytic
poisoning. In some embodiments, all or one of the above described
parameters, including temperature, pressure and flow-rate are
optimized to decrease the production of certain compounds, such as
alkenes.
[0458] The carrier gas used in the reactor can be for example,
hydrogen, nitrogen, argon, carbon monoxide, carbon dioxide, helium
or mixtures thereof. In some embodiments, the carrier gas used in
the reactor can be a mixture of hydrogen and another gas such as
nitrogen containing about 1% hydrogen, about 2% hydrogen, about 3%
hydrogen, about 4% hydrogen, about 5% hydrogen, about 6% hydrogen,
about 7% hydrogen, about 8% hydrogen, about 9% hydrogen, about 10%
hydrogen, about 15% hydrogen, about 20% hydrogen, about 25%
hydrogen, about 30% hydrogen, about 35% hydrogen, about 40%
hydrogen, about 45% hydrogen, about 50% hydrogen, about 55%
hydrogen, about 60% hydrogen, about 65% hydrogen, about 70%
hydrogen, about 75% hydrogen, about 80% hydrogen, about 85%
hydrogen, about 90% hydrogen, and about 95% hydrogen. In one
embodiment, the carrier gas used in the reactors is a mixture of
hydrogen and nitrogen containing about 5% hydrogen.
[0459] In some embodiments, the reaction is carried out using
liquid diluents or carriers such as an alcohol (such as methanol,
ethanol, propanol etc.), dimethylsulfoxide, water, or a mixture
thereof. In some embodiments, the liquid diluents or carrier can
contain a mixture of water and an alcohol containing about 1% of
water by volume, 2% of water by volume, 3% of water by volume, 4%
of water by volume, 5% of water by volume, 6% of water by volume,
7% of water by volume, 8% of water by volume, 9% of water by
volume, 10% of water by volume, 15% of water by volume, 20% of
water by volume, 25% of water by volume, 30% of water by volume,
35% of water by volume, 40% of water by volume, 45% of water by
volume, 50% of water by volume, 55% of water by volume, 60% of
water by volume, 65% of water by volume, 70% of water by volume,
75% of water by volume, 80% of water by volume, 85% of water by
volume, 90% of water by volume, and about 95% of water by
volume.
[0460] In some embodiments, the reactor may be subjected to a
temperature gradient of about 25.degree. C. to about 50.degree. C.,
about 50.degree. C. to about 75.degree. C., about 75.degree. C. to
about 100.degree. C., about 125.degree. C. to about 150.degree. C.,
about 150.degree. C. to about 175.degree. C., about 175.degree. C.
to about 200.degree. C., about 200.degree. C. to about 250.degree.
C., about 250.degree. C. to about 300.degree. C., about 300.degree.
C. to about 325.degree. C., about 325.degree. C. to about
350.degree. C., about 350.degree. C. to about 375.degree. C., about
375.degree. C. to about 400.degree. C., about 400.degree. C. to
about 425.degree. C., about 425.degree. C. to about 450.degree. C.,
about 450.degree. C. to about 475.degree. C., about 475.degree. C.
to about 500.degree. C., about 500.degree. C. to about 1000.degree.
C., or in a range bounded by any numerical value stated herein
above.
[0461] In some embodiments, the reactor may be subjected to a
pressure gradient of about 10 bar to about 25 bar, about 25 bar to
about 50 bar, about 50 bar to about 75 bar, about 75 bar to about
100 bar, about 125 bar to about 150 bar, about 150 bar to about 175
bar, about 175 bar to about 200 bar, about 200 bar to about 250
bar, about 250 bar to about 300 bar, about 300 bar to about 325
bar, about 325 bar to about 350 bar, about 350 bar to about 375
bar, about 375 bar to about 400 bar, about 400 bar to about 425
bar, about 425 bar to about 450 bar, about 450 bar to about 475
bar, about 475 bar to about 500 bar about 500 bar to about 1000
bar, or in a range bounded by any numerical value stated herein
above.
[0462] In some embodiments, the viscosity of the reaction mixture
in the reactor may range from about 1 centipoise (cP) to about 5
Cp, about 5 cP to about 10 cP, about 10 cP to about 15 cP, about 15
cP to about 20 cP, about 20 cP to about 25 cP, about 25 cP to about
30 cP, about 30 cP to about 35 cP, about 40 cP to about 45 cP,
about 45 cP to about 50 cP, about 50 cP to about 55 cP, about 55 cP
to about 60 cP, about 60 cP to about 65 cP, about 65 cP to about 70
cP, about 70 cP to about 75 cP, about 75 cP to about 80 cP, about
80 cP to about 85 cP, about 85 cP to about 90 cP, about 90 cP to
about 95 cP, about 95 cP to about 100 cP, about 100 cP to about 200
cP, about 200 cP to about 300 cP, about 300 cP to about 400 cP,
about 400 cP to about 500 cP, about 500 cP to about 600 cP, about
600 cP to about 700 cP, about 700 cP to about 800 cP, about 800 cP
to about 900 cP, about 900 cP to about 1000 cP, or in a range
bounded by any numerical value stated herein above.
[0463] Many reforming catalysts suffer from catalyst deactivation
over time. The biggest cause of deactivation is the accumulation of
carbon, e.g., coke, on the catalyst surface. One way, coke
formation can be reduced or eliminated is by doping the catalysts
with a suitable organic or inorganic material. Suitable dopants
that can improve the dispersion of the metal catalyst and reduce
the formation of coke include alkali metals (such as Li, Na, and
K), transition metals (such as Ti, Zr, Hf, Nb, Cr, Mo, W, Mn, Re,
Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au), mixtures of
transition metals (such as Ti/Hf, Ti/Zr, Zr/Cr), organometallic
complexes (such as Cp.sub.2 V, (butadiene).sub.3 Mo, Bis-(arene)
complexes of zero-valent Ti, Zr or Hf), promoter metals (such as
germanium, indium, gallium, thallium), rare earth elements (such as
La), halogens (such as fluorine, chlorine, bromine and iodine),
hydrogen, hydrogen sulfide, tin, and sulfur.
[0464] In one embodiment, the catalyst contains about 0.001%, about
0.01%, about 0.1%, about 1%, about 2%, about 3%, about 4%, about
5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%,
about 12%, about 13%, about 14%, about 15%, about 16%, about 17%,
about 18%, about 19%, about 20% by weight of at least one doping
agent.
[0465] The catalyst can also be regenerated if the coke level on
the catalyst is too high. The regeneration of coked catalysts can
be accomplished by flowing a gas stream containing a few percent of
oxygen over the catalyst at elevated temperatures, for example,
0.5% 02 in N2 and H2 at 500.degree. C. The temperature of the
reaction it controlled to avoid exothermic combustion of the
deposited coke so as to prevent sintering of the catalyst.
Regeneration can take place in a variety of reactors, including
adiabatic fixed beds and polytropic reactors (reactors with
multiple inlets).
[0466] The catalysts described herein can be used as bulk catalysts
(e.g., not on a support). Bulk catalysts can be formed into shapes
to increase surface area and allow flow of reactants over its
surface. For example, in the form of: wool, a mesh, a grid, a wire,
a perforated solid with channels, a sponge, beads and/or a powder.
The catalysts and promoters can be mixed when utilized in bulk, for
example powers of one or more catalyst and powders of one or more
promoters can be combined/mixed. The metals or metal with promoter
species can be advantageously adsorbed and or bonded onto a
support. The support can be, for example, alumina, silica,
aluminosilicates, clays, zeolites (e.g., USY and beta zeolite) or
other inorganic materials. The supported catalysts typically have
between about 0.1 wt. % and 10 wt. % of each metal (e.g., between
0.1 and 1 wt.), although higher amounts can be used. One or more
metal and one or more promoter can be combined with one or more
support in all combinations. These supported catalysts may be
formed into any convenient form.
[0467] The catalysts can be homogeneous catalysts, for example,
tris(triphenylphosphine)rhodium(I) chloride, and similar catalysts
wherein the metal is complexed with stabilizing ligand(s) (e.g.,
amines, phosphines, alcohols, ethers, ketones, carboxylates,
acetylacetonates, optionally bis, tri or tetrakis chelating
ligands, combinations of these). The catalyst can be a polymer
supported analog of a homogeneous catalyst, for example, wherein
the ligands are attached to a polymer, e.g., functionalized
polystyrenes wherein the functional groups are the ligands
previously mentioned. Some catalysts, conditions, equipment and
systems that can be utilized herein for the hydrogenolysis and
esterification reaction are described in: "Catalysis of Organic
Reactions" edited John R. Sowa, Jr., CRC Press (2005); "Catalytic
Naphtha Reforming Second Edition, Revised and Expanded" edited
George J. Antos and Abdullah M. Aitani, Marcel Dekker (2005)
chapters 6, 8 and 9; and "Steam reforming catalysts Natural gas,
associated gas and LPG" Johnson Matthey, pages 1-15. For example,
bi and tri metallic supported catalysts of SnRu and SnRePt can be
utilized for the hydrogenolysis of ethyl butyrate.
[0468] Supported catalysts can be prepared by any useful means, for
example, by using the incipient wetness method, a decomposition
precipitation method, a solution self-assembly method, and/or by
vapor phase deposition/decomposition. For example, utilizing the
incipient wetness method, a desired metal precursor can be
dissolved or suspended in a volume of solvent similar to the pore
volume of the support and it is combined with the support. The
catalyst can be activated. Activation can include removal of the
solvent under vacuum, calcination, for example in the presence of
oxygen, nitrogen, hydrogen or other gasses, in any order and
repeatedly. The catalysts can be added before the promoter, with
the promoter, after the promoter or in combinations of addition
steps. The supported catalysts can be formed into beads or extruded
into rods and other shapes. Often these are combined with binders
(e.g., inert ceramic material, porous binders).
[0469] Catalysts can be utilized in a batch mode. For example, the
ester is combined, often with a solvent, in a vessel (e.g., a
Parr.TM. reactor). The vessel can be sparged with hydrogen and/or
pressurized with hydrogen. The vessels can be equipped with
heaters, (e.g., heating jackets) and agitators (e.g., propellers,
impellers). The catalysts can also be utilized in a fluidized bed
reactor. These require a high gas flow rate, e.g., of an inert gas
(e.g., nitrogen, He, Ar) in addition to hydrogen and the ester. The
catalyst is fluidized by the rapid flow of gases through the
reactor. One or more catalysts can be utilized sequentially or in
combination (e.g., mixed together). A loop reactor may be used as
it is a design option of a batch reactor, except the liquid in the
vessel is recirculated outside of the reactor. If utilized
sequentially, the catalysts can be utilized under different
reaction conditions, e.g., temperatures, pressures (e.g., hydrogen
pressures) and/or agitation (e.g., stirring rates). These
combinations can, for example, optimize throughputs and combined
conversion/selectivity.
[0470] Optionally, the catalysts are utilized in a fixed bed flow
reactors (e.g., a flow reactor, packed bed reactor, trickle bed
reactor). For example, a trickle-bed reactor (TBR) is a chemical
reactor that uses the downward movement of a liquid and the
downward (co-current) or upward (counter-current) movement of gas
over a packed bed of (catalyst) particles. It is considered to be
the simplest reactor type for performing catalytic reactions where
a gas and liquid (normally both reagents) are present in the
reactor and accordingly it is extensively used in processing
plants. Typical examples are liquid-phase hydrogenation,
hydrodesulfurization, and hydrodenitrogenation in refineries (three
phase hydrotreater). These reactors are configured as a column
packed with the catalysts (e.g., bulk or supported catalyst)
through which the reactants (e.g., esters and hydrogen) are flowed.
The columns can be heated, for example, by a heating jacket charged
with a heating fluid (e.g., water, high pressure water, oil),
steam, electric heaters (e.g., resistive heating), or any other
heating means. The columns can also be designed to withstand high
pressures e.g., at least about 50 psi, at least about 100 psi, at
least about 150 psi, at least about 200 psi, at least about 300
psi, at least about 500 psi. The columns can also be equipped with
safety equipment e.g., pressure release valves, and high
temperature process shut off (e.g., flow shut off, venting).
Optionally, two or more fixed bed reactors can be utilized in
series for one flow stream of reactants (e.g., up to 20, up to 10,
2 to 5, 3 to 10, 1 to 3). In some optional configurations some of
the reactors are by-passed, for example, to keep them as a backup.
Having available backups is particularly useful to avoid down time
when one or more of the flow reactors are not operating within
acceptable parameters e.g., if catalysts in the reactor are
deactivated. Another advantage of utilizing reactors in series is
that the reactors can be charged with different catalysts, for
example having different selectivity and conversion rates, for
optimal throughputs and combined conversion/selectivity. The
columns can also be run under different conditions, e.g., flow
rates, pressures and temperatures. For example, two or more columns
can be utilized wherein the difference in temperatures can be about
0 to 10.degree. C. (e.g., about 10 to 200.degree. C., about 50 to
200.degree. C., about 50 to 150.degree. C., about 50 to 100.degree.
C.). In addition to or alternatively the difference in pressure
(e.g., hydrogen pressure) when using at least more than one column,
can be between about 0 to 5 atm. (e.g. between about 5 and 50 atm.,
between about 10 and 50 atm., between about 30 and 50 atm.).
[0471] The catalysts as described can be recycled/regenerated. For
example, often the catalysts are oxidized by heating to high
temperature in an oxidizing environment (e.g., in the presence of
oxygen) e.g., between about 200 and 800.degree. C. (e.g., 400 to
600.degree. C.). After purging with an inert gas (e.g., nitrogen,
argon, helium) the catalysts are reduced at a high temp e.g.,
between about 200 and 800.degree. C. The reducing agent, for
example, can be hydrogen gas made to flow over the catalyst.
[0472] Catalyst deactivation, the loss over time of catalytic
activity and/or selectivity, is a problem of great and continuing
concern in the practice of industrial catalytic processes. In one
aspect, provided herein are methods of reducing catalytic
deactivation, by either developing deactivation-resistant catalysts
or providing methods of regenerating catalysts from deactivated
catalysts.
[0473] Catalysts can be deactivated by various mechanisms, such as
poisoning (strong chemisorption of species on catalytic sites which
block sites for catalytic reaction), fouling (physical deposition
of species from fluid phase onto the catalytic surface and in
catalyst pores), thermal degradation and sintering (thermally
induced loss of catalytic surface area, support area, and active
phase-support reactions), vapor formation (reaction of gas with
catalyst phase to produce volatile compound), vapor-solid,
liquid-solid and solid-solid reactions, attrition and crushing
(loss of catalytic material due to abrasion; loss of internal
surface area due to mechanical-induced crushing of the catalyst
particle).
[0474] Catalyst deactivators can include a number of materials,
such as carbonized material (eg., coke), hydrogen, carbon monoxide,
sulfur oxides, phosphorus oxides, inorganic ions such as halide,
cyanide, sulfide, sulfite, and phosphite, and organic molecules
such as nitriles, amine, thiols, nitro-compounds, oximes,
nitrogen-containing heterocycles, benzene, acetylene, other
unsaturated hydrocarbons, and certain metals and metal ions (such
as As, Pb, Hg, Bi, Sn, Cd, Cu, Fe). For example, FIG. 17A shows
that even in a fresh Pt-containing catalyst (eg., TVG-105), some
amount of carbon deposition is observed. The figure depicts the
element-profile of the catalyst. In this instance, 14% by weight of
carbon was observed on the fresh, unused catalyst. Without being
bound by hypothesis, it is possible that the carbon deposition took
place during the process of securing the catalyst into the
processing system. Alternatively, the carbon may have been
deposited during catalyst production. FIG. 17B, provides an example
of the element-profile of the same catalyst (TVG-105) after it has
been used for catalytic conversion. As indicated by the figure, the
amount of the carbon deposited on the used catalyst almost doubled
to about 27.5% by weight. On the other hand, the amount of Pt was
below the detection threshold of the analysis, indicating that the
carbon deposition was covering the platinum surface, and was likely
one of the causes of the loss of catalytic activity, that was
observed with this catalyst.
[0475] In some embodiments, the catalytic deactivation can be
reduced by generating deactivation-resistant catalysts. In some
embodiments, catalytic deactivation can be reduced by controlling
catalyst properties, process conditions (i.e., temperatures,
pressures), feedstock impurities, methods of contacting, and
process design. In some embodiments, the impact of catalytic
deactivation may be reduced by regenerating the catalysts or
separating the deactivating material from the catalysts.
[0476] In some embodiments, deactivation-resistant catalytic
compositions are generated by designing catalytic compositions of
certain pore sizes. For example, an optimal pore size can be
designed to prevent access of large deactivating molecules to the
catalytic ions, but allowing easy access to the reactant molecules.
For example, the catalytic composition may have a pore-size of
about the same size as that of the reactant molecule, about 2
times, about 3 times, about 4 times, about 5 times, about 6 times,
about 7 times, about 8 times, about 9 times, about 10 times, about
11 times, about 12 times, about 13 times, about 14 times, about 15
times, about 16 times, about 17 times, about 18 times, about 19
times, about 20 times, about 30 times, about 40 times, about 50
times, about 60 times, about 70 times, about 80 times, about 90
times, about 100 times the size of the reactant molecule, and any
size between any of the above pore sizes. In some embodiments, the
catalytic composition may have a pore-size less than the size of
the deactivating molecules, about 0.9 times the size of the
deactivating molecule, about 0.8 times the size of the deactivating
molecule, about 0.7 times the size of the deactivating molecule,
about 0.6 times the size of the deactivating molecule, about 0.5
times the size of the deactivating molecule, about 0.4 times the
size of the deactivating molecule, about 0.3 times the size of the
deactivating molecule, about 0.2 times the size of the deactivating
molecule, about 0.1 times the size of the deactivating molecule,
about 0.01 times the size of the deactivating molecule, about 0.001
times the size of the deactivating molecule, and any size between
any of the above pore sizes. In some embodiments, the catalytic
composition may have a pore size of about 10 to about 20 .ANG.,
about 20 to about 30 .ANG., about 30 to about 40 .ANG., about 40 to
about 50 .ANG., about 50 to about 60 .ANG., about 60 to about 70
.ANG., about 70 to about 80 .ANG., about 80 to about 90 .ANG.,
about 90 to about 100 .ANG., about 100 to about 150 .ANG., about
150 to about 200 .ANG., about 200 to about 250 .ANG., about 250 to
about 300 .ANG., about 300 to about 350 .ANG., about 350 to about
400 .ANG., about 400 to about 450 .ANG., about 450 to about 500
.ANG., about 500 to 1000 .ANG., or in a range bounded by any
numerical value stated herein above.
[0477] In some embodiments, deactivation-resistant catalytic
compositions are generated by designing catalytic compositions of
certain surface area. For example, the catalysts can have a surface
area of about 1 m.sup.2/g, about 10 m.sup.2/g, about 20 m.sup.2/g,
about 30 m.sup.2/g, about 40 m.sup.2/g, about 50 m.sup.2/g, about
60 m.sup.2/g, about 70 m.sup.2/g, about 80 m.sup.2/g, about 100
m.sup.2/g, about 110 m.sup.2/g, about 120 m.sup.2/g, about 130
m.sup.2/g, about 140 m.sup.2/g, about 150 m.sup.2/g, about 160
m.sup.2/g, about 170 m.sup.2/g, about 180 m.sup.2/g, about 190
m.sup.2/g, about 200 m.sup.2/g, about 210 m.sup.2/g, about 220
m.sup.2/g, about 230 m.sup.2/g, about 240 m.sup.2/g, about 250
m.sup.2/g, about 260 m.sup.2/g, about 270 m.sup.2/g, about 280
m.sup.2/g, about 290 m.sup.2/g, about 300 m.sup.2/g, about 310
m.sup.2/g, about 320 m.sup.2/g, about 330 m.sup.2/g, about 340
m.sup.2/g, about 350 m.sup.2/g, about 360 m.sup.2/g, about 370
m.sup.2/g, about 380 m.sup.2/g, about 390 m.sup.2/g, about 400
m.sup.2/g, about 410 m.sup.2/g, about 410 m.sup.2/g, about 410
m.sup.2/g, about 420 m.sup.2/g, about 430 m.sup.2/g, about 440
m.sup.2/g, about 450 m.sup.2/g, about 460 m.sup.2/g, about 470
m.sup.2/g, about 480 m.sup.2/g, about 500 m.sup.2/g, about 550
m.sup.2/g, about 600 m.sup.2/g, about 650 m.sup.2/g, about 700
m.sup.2/g, about 750 m.sup.2/g, about 800 m.sup.2/g, about 850
m.sup.2/g, about 900 m.sup.2/g, about 950 m.sup.2/g, and about 1000
m.sup.2/g.
[0478] In some embodiments, deactivation-resistant catalytic
compositions are generated by designing catalytic compositions of
certain pore volume. For example, the catalyst can have a pore
volume of about 0.01 cm.sup.3/g, about 0.02 cm.sup.3/g, about 0.03
cm.sup.3/g, about 0.04 cm.sup.3/g, about 0.05 cm.sup.3/g, about
0.06 cm.sup.3/g, about 0.07 cm.sup.3/g, about 0.08 cm.sup.3/g,
about 0.09 cm.sup.3/g, about 0.1 cm.sup.3/g, about 0.2 cm.sup.3/g,
about 0.3 cm.sup.3/g, about 0.4 cm.sup.3/g, about 0.5 cm.sup.3/g,
about 0.6 cm.sup.3/g, about 0.7 cm.sup.3/g, about 0.8 cm.sup.3/g,
about 0.9 cm.sup.3/g, about 1.0 cm.sup.3/g, about 1.1 cm.sup.3/g,
about 1.2 cm.sup.3/g, about 1.3 cm.sup.3/g, about 1.4 cm.sup.3/g,
about 1.5 cm.sup.3/g, about 1.6 cm.sup.3/g, about 1.7 cm.sup.3/g,
about 1.8 cm.sup.3/g, about 1.9 cm.sup.3/g, about 2.0 cm.sup.3/g,
about 2.1 cm.sup.3/g, about 2.2 cm.sup.3/g, about 2.3 cm.sup.3/g,
about 2.4 cm.sup.3/g, about 2.5 cm.sup.3/g, about 2.6 cm.sup.3/g,
about 2.7 cm.sup.3/g, about 2.8 cm.sup.3/g, about 2.9 cm.sup.3/g,
about 3.0 cm.sup.3/g, about 3.1 cm.sup.3/g, about 3.2 cm.sup.3/g,
about 3.3 cm.sup.3/g, about 3.4 cm.sup.3/g, about 3.5 cm.sup.3/g,
about 3.6 cm.sup.3/g, about 3.7 cm.sup.3/g, about 3.8 cm.sup.3/g,
about 3.9 cm.sup.3/g, about 4.0 cm.sup.3/g, about 4.1 cm.sup.3/g,
about 4.2 cm.sup.3/g, about 4.3 cm.sup.3/g, about 4.4 cm.sup.3/g,
about 4.5 cm.sup.3/g, about 4.6 cm.sup.3/g, about 4.7 cm.sup.3/g,
about 4.8 cm.sup.3/g, about 4.9 cm.sup.3/g, about 5.0 cm.sup.3/g,
about 5.1 cm.sup.3/g, about 5.2 cm.sup.3/g, about 5.3 cm.sup.3/g,
about 5.4 cm.sup.3/g, about 5.5 cm.sup.3/g, about 5.6 cm.sup.3/g,
about 5.7 cm.sup.3/g, about 5.8 cm.sup.3/g, about 5.9 cm.sup.3/g,
about 6.0 cm.sup.3/g, about 7.0 cm.sup.3/g, about 8.0 cm.sup.3/g,
about 9.0 cm.sup.3/g, and about 10.0 cm.sup.3/g.
[0479] In some embodiments, the formation of catalytic deactivation
can be reduced by choosing appropriate reaction conditions. For
example, catalytic deactivation may be reduced by introducing
gasifying agents (e.g., H.sub.2, H.sub.2O, O.sub.2) or gas
diluents, and by minimizing the void space available for
homogeneous reaction. Similarly, the formation and growth of carbon
or coke species on metal surfaces can be minimized by choosing
reaction conditions that minimize the formation of atomic carbon or
coke precursors and by introducing gasifying agents. Selective
membranes or supercritical conditions can also be used to lower the
gas-phase and surface concentrations of coke precursors. In some
embodiments, moving-bed reactors may be preferred over fixed-bed
reactors to prevent the deposition of deactivators on the
catalysts.
[0480] In some embodiments, deactivation-resistant catalytic
compositions are generated by modifying the catalytic composition.
For example, catalytic compositions can be designed, which prevent
catalyst deactivators from sticking to the surface or pores of a
catalyst, by treatment with colloidal dispersions, or lubricants.
In some embodiments, introduction of modifiers that change ensemble
sizes (e.g., Cu or S in Ni or Ru) or that lower the solubility of
deactivators such as carbon (e.g., Pt in Ni) can be used in
reducing deactivation. In some embodiments, deactivation can be
reduced by modifying the acidity and basicity of the catalytic
composition. In some embodiments, some coating (eg., alumina or
zeolite coating) can be applied to the catalytic material, or the
catalyst can be prepared such that the active phase is in a
sublayer, thereby providing a diffusion barrier that prevents or
slows the access of deactivators to the catalyst surface. In some
embodiments, catalysts may include "traps" for deactivating
molecules (eg., oxides of thulium, cerium, and zinc), which can act
as sacrificial stoichiometric reactants to protect the active
catalyst by preferentially adsorbing the deactivators. For example,
the formation of catalytic deactivators such as coke or carbon can
be reduced by choosing reaction conditions that minimize the
formation of free radicals, or by using free-radical traps. In some
embodiments, the catalysts are produced in morphologically
advantageous form, such that deactivators can be readily removed
from them. Examples of advantageous morphological changes include
modification of the shape, texture, density, viscosity, strength
and crystallinity of the catalytic compositions.
[0481] Several catalytic and non-catalytic materials, can be
advantageously used to improve deactivation-resistance of catalysts
including silica, alumina, magnesium, zirconia, boria, titania
chromia and combinations thereof, combinations of inorganic oxide
typified by silica-alumina, silica-zirconia, silica-boria,
silica-magnesia, silica-titania or ternary combinations such as
silica-alumina-zirconia, silica-alumina-magnesia, particularly with
silica as silica-alumina and silica-magnesia-alumina. In some
embodiments, zeolite catalytic material, including X and Y
aluminosilicate zeolites, ZSM-4, ZSM-5, ZSM-11, ZSM-12, ZSM-35,
ZSM-38 and other similar materials, such as erionite, mordenite and
faujasite, may also be useful in improving resistance to catalyst
deactivation.
[0482] In some embodiments, the catalytic compositions are designed
such that catalyst deactivators can be removed from them upon
certain type of treatment. Both chemical and mechanical treatments
may be used. For example, the deactivated catalysts can be
subjected to shaking, spinning, abrasion, elution with gas or
liquid, sonication, heating, drying, pressure-treatment,
irradiation and treatment with magnetic forces.
[0483] In one embodiment, carbonaceous deposits can be removed by
gasification with O.sub.2, H.sub.2O, CO.sub.2, and H.sub.2. The
temperature required to gasify these deposits at a reasonable rate
can be varied with the type of gas, the structure and reactivity of
the carbon or coke, and the activity of the catalyst.
[0484] In some embodiments, the removal of deactivators may be
accomplished by using a combination of treatment methods. For
example, the catalysts may be subjected to a sequence of treatment
steps, such as a first step involving treatment with a compressed
gas, a second step involving washing the catalyst in a suitable
solution, a third step involving rinsing, and a fourth step
involving drying. In another example, a catalyst regeneration
procedure can include the following steps: (1) vigorous shaking;
(2) pressurized wet and dry treatments to remove channel blockages
and outer dust layers; (3) washing of catalyst units in tanks
containing agitated water augmented with surfactants, dispersants,
ion-exchange materials, emulsifiers, acid, base, and/or acoustic
radiation; (4) rinsing repeatedly in deionized water and repeating
ultrasonic treatments between or in concert with chemical
treatments, with a final rinse to finish removal of any catalyst or
fouling residue; (5) reimpregnation of the clean support with the
catalyst; and (5) drying (calcining) at low heating rates to
convert the salts of the active catalytic materials to active metal
oxides.
[0485] The deactivating material that is separated from the
catalyst during the process of catalyst-regeneration, can be
collected and used as commercially value-added products, or as
building blocks or constituents of commercially value-added
products. For example, carbon in the form of charcoal and coke can
be used in metal smelting, in industries such as the iron and steel
industries. Carbon in the form of graphite can be used in pencils,
to make brushes in electric motors and in furnace linings.
Activated charcoal can be used for purification and filtration,
example in respirators and kitchen extractor hoods. Carbon fiber
generated from carbon can be used strong, yet lightweight, material
in many products such as tennis rackets, skis, fishing rods,
rockets and airplanes. Carbon can also be used to prepare carbon
nanotubes, fullerenes and atom-thin sheets of graphene, which can
be used for example, in hardware developments in the electronics
industry and in nanotechnology.
Syngas-to-Fuel
[0486] In one embodiment, gasification can be employed to generate
fuel gases along with various other gaseous, liquid, and solid
products. To perform gasification, the pre-treated feedstock is
introduced into a pyrolysis chamber and heated to a high
temperature, typically 700.degree. C. or more. The temperature used
depends upon a number of factors, including the nature of the
feedstock and the desired products.
[0487] Quantities of oxygen (e.g., as pure oxygen gas and/or as
air) and steam (e.g., superheated steam) are also added to the
pyrolysis chamber to facilitate gasification. These compounds react
with carbon-containing feedstock material in a multiple-step
reaction to generate a gas mixture called synthesis gas (or
"syngas"). Essentially, during gasification, a limited amount of
oxygen is introduced into the pyrolysis chamber to allow some
feedstock material to combust to form carbon monoxide and generate
process heat. The process heat can then be used to promote a second
reaction that converts additional feedstock material to hydrogen
and carbon monoxide.
[0488] In a first step of the overall reaction, heating the
feedstock material produces a char that can include a wide variety
of different hydrocarbon-based species. Certain volatile materials
can be produced (e.g., certain gaseous hydrocarbon materials),
resulting in a reduction of the overall weight of the feedstock
material. Then, in a second step of the reaction, some of the
volatile material that is produced in the first step reacts with
oxygen in a combustion reaction to produce both carbon monoxide and
carbon dioxide. The combustion reaction releases heat, which
promotes the third step of the reaction. In the third step, carbon
dioxide and steam (e.g., water) react with the char generated in
the first step to form carbon monoxide and hydrogen gas. Carbon
monoxide can also react with steam, in a water gas shift reaction,
to form carbon dioxide and further hydrogen gas.
[0489] Multiple gasification technologies exist to convert
reduced-size biomass to syngas. In one embodiment, a
high-temperature (slagging) gasification process is used, wherein
the biomass is pressurized and converted into raw synthesis gas
during gasification at temperatures around 1300.degree. C. in the
presence of high purity oxygen and steam. A combustor is included
to provide heat to dry the biomass. A direct-quench syngas cooling
system next to the gasifier removes ash and tars. A water-gas-shift
system after quench is applied to adjust the H.sub.2:CO ratio to
2.1:1.
[0490] In another embodiment, the endothermic gasification process
is indirectly-heated by the circulation of hot olivine and the
material in the gasifier is fluidized by the steam. Gasification
occurs at atmospheric conditions and at 880.degree. C. The syngas
is further conditioned such that the residual tars, methane and
light hydrocarbons are reformed to syngas in a fluid catalytic
cracker. Water gas shift also occurs in the reformer. Compared to
the high temperature gasification, this design has the benefits of
energy self-sufficient, improved capital cost associated with the
smaller process scale, and neutral electrical energy.
[0491] Other than syngas, a number of products, including pyrolysis
oils and gaseous hydrocarbon-based substances, can also be obtained
during and/or following gasification; these can be separated and
stored or transported as desired.
[0492] In one embodiment, liquid hydrocarbon fuels and liquid
alcohols can be produced catalytically from the syngas through a
Fischer-Tropsch (F-T) process. After syngas is produced, it is
polished with zinc oxide and an activated carbon sorbent and
compressed to 25 bar, the F-T operating pressure. H.sub.2 used in
the hydro-processing stage can be purified through a pressure swing
adsorption. The syngas is then processed by F-T synthesis to
produce liquid fuel. Various catalysts, such as those based on
transition metals iron, cobalt, nickel and ruthenium can be used.
Product selectivity and product distribution depend strongly on the
operating temperature and the partial pressure of the gases that
contact the catalyst.
[0493] There are two well-known F-T operating modes; high
temperature and low temperature. The high-temperature process runs
at 300-350.degree. C. with iron-based catalysts. Gasoline and
linear low-molecular-mass olefins are produced in this process. The
low-temperature process operates at 200-240.degree. C. with either
iron or cobalt catalysts. Linear waxes produced in the
low-temperature process have higher molecular mass than those
produced in the high-temperature process. In the F-T process, the
products range from methane to long-chain hydrocarbons. Besides
alkanes and alkenes, oxygenated compounds such as alcohols,
aldehydes, and carboxylic acids are also formed. Aromatics and
ketones are also produced in the high temperature process. The F-T
process is a highly exothermic process; therefore, the heat of
reaction has to be removed quickly to avoid overheating and
deactivating the catalyst and also to prevent production of
undesired methane.
[0494] Conventional refinery processes, such as hydrocracking,
isomerization, hydrogenation, and fractionation, can be applied to
upgrade the F-T synthesis product to high-quality, low-aromatic,
and almost zero-sulfur-content fuels. Hydrocracking/isomerization
is used to convert the wax into lighter products with shorter chain
length and lower boiling points. Products from the hydrocracking
isomerization reactor are heated and distilled to produce jet fuel,
diesel fuel, and lubricants. Hydrogenation is applied to produce
naphtha from the F-T liquid. The F-T tail gas, which contains
H.sub.2, water, methane, CO, CO.sub.2, nitrogen, argon, and heavier
hydrocarbons, is recycled back to the syngas generation system.
H.sub.2 in the tail gas can be purified through a pressure swing
absorber and can be further used in the hydrocracking/isomerization
process.
[0495] F-T fuels are typically free of sulfur and contain very few
aromatics compared to gasoline and diesel, which leads to lower
emissions when used in jet engines. The use of the F-T technology
to convert biomass to synthetic fuels may provide a promising
carbon-neutral alternative to conventional diesel, kerosene, and
gasoline.
[0496] Instead of catalytically upgrading syngas to fuel, it is
also possible to ferment syngas to liquid biofuels. For example,
lignocellulosic biomass is converted into syngas via gasification,
and the cooled syngas is then fermented to ethanol or butanol by
acetagenic bacteria. The acetogenic bacteria Clostridium is used to
consume CO and H.sub.2 to produce ethanol and 2,3-butanediol. Other
products such as acetate, acetone, isopropanol, and butanol can be
produced by other biosynthetic pathways with different microbe
strains. The mixed alcohol, ethanol, or 2,3-butanediol can be
upgraded into jet fuel via previously described methods that
include dehydration, oligomerization, distillation, and
hydrogenation processes.
[0497] Syngas fermentation has several potential advantages over
catalytic upgradation. It is able to produce more products than the
traditional biochemical or thermochemical pathways and it has an
overall energy efficiency of 57%. The process requires lower
temperature and pressure, as well as less expensive enzymes. Gas
fermentation can convert not only energy crops and typical
agricultural wastes, but also municipal and industrial organic
waste.
Bio-Oil to Fuel
[0498] In some embodiments, processed biomass can be converted to
stable, concentrated bio-oil (biocrude) by the processes described
herein. The bio-oil can be compatible with existing refinery
technology as well as can be converted into advanced fuels. For
example, in a hydrothermal upgrading process, biomass can be
treated with water at high temperature and pressure
(300-350.degree. C. & 120-180 bar) to produce bio-oil. This can
be separated by flashing or extraction to heavy crude (suitable for
co-combustion in coal power stations) and light crude, which can be
catalytically upgraded to fuels.
[0499] In one embodiment, bio-oil can be converted to fuel
components using the following steps. Catalytic hydrogenation can
be used to convert liquid-phase unsaturated fatty acids or
glycerides into saturated ones with the addition of hydrogen; the
glycerol portion of the triglyceride molecule is turned into
propane by adding H.sub.2. The next step involves cleaving the
propane to form three moles of free fatty acids (FFAs).
[0500] In another embodiment, glycerides can be converted to FFAs
by a process called thermal hydrolysis. Oils and fats that contain
mostly triglycerides are converted into three moles of FFAs and one
mole of glycerol by processing the feedstocks with three moles of
water. High temperature (250-260.degree. C.) is required for water
to dissolve in the oil phase. High pressure is also necessary to
maintain the reactants in liquid phase.
[0501] In another embodiment, catalytic hydro-thermolysis (CH) also
named hydrothermal liquefaction is used. The hydrothermal process
contains a series of reactions, including cracking, hydrolysis,
decarboxylation, isomerization, and cyclization, that turn
triglycerides into a mixture of straight chain, branched, and
cyclic hydrocarbons. The CH reaction is conducted at temperatures
from 450.degree. C. to 475 C..degree. and pressures of 210 bar with
water and a catalyst (or without a catalyst). The resulting
products-including carboxylic acids, oxygenated species, and
unsaturated molecules--are sent through decarboxylation and
hydrotreating processes for saturation and oxygen removal. The
treated products, ranging from 6 to 28 carbon numbers, contain
n-alkanes, iso-alkanes, cyclo-alkanes, and aromatics, which require
a fractionation step for separation to naphtha, jet fuel, and
diesel fuel.
[0502] Alternatively, pyrolysis oil can be upgraded to hydrocarbon
fuels, including jet fuel, through integrated pyrolysis and
hydro-conversion. This integrated biorefinery system can combine
commercial RTP (Rapid Thermal Processing) pyrolysis technology with
catalytic hydroconversion. The resulting hydrocarbon components can
be separated by batch vacuum distillation.
EXAMPLES
Example 1
General Method for Alumina-Based Catalyst Preparation
[0503] Stream chemical alumina (high purity .gamma.-alumina,
150-200 m.sup.2/g) was used as the support for metals (e.g., Pt,
Pd, Sn, Ba, Bi) in catalyst preparation. The catalyst was prepared
by an incipient wetness impregnation method. The volume of the
de-ionized water used to dissolve the metal precursors was equal to
the pore volume of the alumina support (0.7 cm.sup.3/g). After
impregnation, the catalyst samples were dried at room temperature
for 3 h, and subsequently for 12 h at 110.degree. C. in vacuum
dried oven. Finally, these catalysts were calcined under air at
500.degree. C. for 3 h.
Example 2
Preparation of Metal/ZSM-5 Catalysts
[0504] Metal (e.g., Ru, Pt and Pd)/HZSM-5 catalysts were prepared
by incipient wetness impregnation method. Zeolite HZSM-5 was
procured from ACS materials. The metal precursor salts used for the
catalyst preparation were Ruthenium Chloride (RuCl.sub.6),
Hexachloroplatinic acid (H.sub.2PtCl.sub.6), Palladium (II)
Chloride (PdCl.sub.6.XH.sub.2O). Predetermined amounts of metal
salts dissolved in De-ionized (DI) water were added dropwise to the
zeolite. After the completion of the addition of the metal salts,
the metal impregnated zeolite was kept at room temperature for 3 h.
Subsequently, the catalyst was dried at 110.degree. C. for 10 h in
a vacuum dried oven and calcined under air at 500.degree. C. for
3h.
Example 2A: 0.5% Pt/HZSM-5 Catalyst
[0505] The catalyst was prepared by incipient wetness impregnation
method. About 3.3 grams of H.sub.2PtCl.sub.6 xH.sub.2O solution
(8%, Sigma Aldrich) was dissolved in 15 mL of de-ionized water.
This solution was added drop-wise to the 25 grams of HZSM-5 support
with proper mixing. Finally, the catalyst was dried at 110.degree.
C. for 10h under vacuum oven and then calcined under air at
500.degree. C. for 3h.
Example 2B: 0.5% Pd/HZSM-5 Catalyst
[0506] The catalyst was prepared by incipient wetness impregnation
method. About 0.2095 grams of PdCl.sub.3 was dissolved in 15 mL of
de-ionized water. This solution was added drop-wise to the 25 grams
of HZSM-5 support with proper mixing. Finally, the catalyst was
dried at 110.degree. C. for 10h under vacuum oven and then calcined
under air at 500.degree. C. for 3h.
Example 2C: 0.5% Ru/HZSM-5 Catalyst
[0507] The catalyst was prepared by incipient wetness impregnation
method. About 0.62128 grams of RuCl.sub.3 xH.sub.2O (40-43% Ru
content) was dissolved in 15 mL of de-ionized water. This solution
was added drop-wise to the 25 grams of HZSM-5 support with proper
mixing. Finally, the catalyst was dried at 110.degree. C. for 10h
under vacuum oven and then calcined under air at 500.degree. C. for
3h.
Example 3
Preparation of Alumina Supported Catalysts
Example 3A: 0.5% Pt-0.5% Sn/Al.sub.2O.sub.3
[0508] Bimetallic Pt--Sn catalyst was prepared by a sequential
incipient wetness impregnation method. The metal precursor salts
used for generating this catalyst were Hexachloroplatinic acid
(H.sub.2PtCl.sub.6), and Tin (II) Chloride (SnCl.sub.6.XH.sub.2O).
In the first step, 0.5% Sn/Al.sub.2O.sub.3 catalyst was prepared.
SnCl.sub.6 (0.2436 grams) was dissolved in 17.5 ml of DI water and
two drops of conc. HCl was added to dissolve the metal salt. This
metal salt solution was then added dropwise to 25 grams of
Al.sub.2O.sub.3 with proper mixing. After the completion of the
addition, the Sn-alumina catalyst was dried at 110.degree. C. for
10h under vacuum oven. The catalyst was then calcined under air at
500.degree. C. for 3h. In the second step, the 0.5%
Sn/Al.sub.2O.sub.3 catalyst was impregnated with Pt. 3.3 grams of
H.sub.2PtCl.sub.6.xH.sub.2O (8% Sigma Aldrich) was dissolved in
14.2 ml of 0.2M HCl and added dropwise to the 0.5%
Sn/Al.sub.2O.sub.3 catalyst. Subsequently, the catalyst was dried
at 110.degree. C. for 10 h in a vacuum oven and calcined under air
at 500.degree. C. for 3h. This method is also used in preparation
of Pt--Sn/Al.sub.2O.sub.3 catalysts containing different amounts of
Pt and Sn, such as 0.1 to 20% Pt (w/w) and 0.1% to 20% Sn (w/w),
and different combinations thereof.
Example 3B: 0.5% Pt-0.5%/Al.sub.2O.sub.3
[0509] Bimetallic Pt--Bi catalyst was prepared by a sequential
incipient wetness impregnation method similar to the one used in
preparing the Pt--Sn/Al.sub.2O.sub.3 catalyst above. Initially
0.2975 grams of Bi(NO.sub.3).sub.3.2H.sub.2O was dissolved in 17.5
mL of de-ionized water. To this solution, 0.5 mL of concentrated
HNO.sub.3 was added to completely dissolve of the metal precursor.
This solution was added drop-wise to the 25 grams of
Al.sub.2O.sub.3 support with proper mixing. After that, the 0.5%
Bi/Al.sub.2O.sub.3 catalyst was dried at room temperature for 3h
then dried at 110.degree. C. for 10 h under vacuum oven, and
subsequently, calcined under air at 500.degree. C. for 3h. Then,
3.3 grams of H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma
Aldrich) was dissolved in 14.2 mL, to which 0.2M HCl was added.
This solution was added drop-wise to the 25 grams of 0.5%
Bi/Al.sub.2O.sub.3 catalyst with proper mixing. Finally, the
catalyst was dried at 110.degree. C. for 10 h under vacuum oven and
then calcined under air at 500.degree. C. for 3h. This method is
also used in preparation of Pt-- Bi/Al.sub.2O.sub.3 catalysts
containing different amounts of Pt and Bi, such as 0.1 to 20% Pt
(w/w) and 0.1% to 20% Bi (w/w), and different combinations
thereof.
Example 3C: 0.5% Pt-0.5% Ba/Al.sub.2O.sub.3
[0510] Bimetallic Pt--Ba catalyst was prepared by a sequential
incipient wetness impregnation method similar to the one used in
preparing the Pt--Sn/Al.sub.2O.sub.3 catalyst above. Initially,
0.1846 grams of Ba(NO.sub.3).sub.2 (99.5%) was dissolved in 17.5 mL
of de-ionized water, and this solution was added drop-wise to the
25 grams of Al.sub.2O.sub.3 support with proper mixing. After that,
the 0.5% Ba/Al.sub.2O.sub.3 catalyst was dried at room temperature
for 3h then dried at 110.degree. C. for 10 h under vacuum oven, and
subsequently calcined under air at 500.degree. C. for 3h. Then, 3.3
grams of H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma Aldrich)
was dissolved in 14.2 mL, to which 0.2M HCl was added. This
solution was added drop-wise to the 25 grams of 0.5%
Ba/Al.sub.2O.sub.3 catalyst with proper mixing. Finally, the
catalyst was dried at 110.degree. C. for 10 h under vacuum oven and
then calcined under air at 500.degree. C. for 3h. This method is
also used in preparation of Pt--Ba/Al.sub.2O.sub.3 catalysts
containing different amounts of Pt and Ba, such as 0.1 to 20% Pt
(w/w) and 0.1% to 20% Ba (w/w), and different combinations
thereof.
Example 3D: 0.5% Pt-0.5% Sn-0.5% Re/Al.sub.2O.sub.3
[0511] Trimetallic Pt--Sn--Re catalyst was prepared by sequential
incipient wetness impregnation method. Initially, 0.2975 g ammonium
perrhenate (NH.sub.4ReO.sub.4) was dissolved in 17.5 mL of
de-ionized water, and this solution was added drop-wise to the 25
grams of Al.sub.2O.sub.3 support with proper mixing. After that,
the catalyst at room temperature for 3h then dried at 110.degree.
C. for 10 h under vacuum oven to produce the 0.5%
Re/Al.sub.2O.sub.3 catalyst. Then, 0.2436 grams of
SnCl.sub.2.2H.sub.2O was dissolved in 17.5 mL of de-ionized water,
and two drops of concentrated HCl was added to this solution to
completely dissolve the metal precursor. This solution was then
added drop-wise to the 25 grams of 0.5% Re/Al.sub.2O.sub.3 catalyst
with proper mixing. After that, the catalyst was dried at room
temperature for 3h then dried at 110.degree. C. for 10 h under
vacuum oven. Subsequently, the catalyst calcined under air at
500.degree. C. for 3h. In the next step, 3.3 grams of
H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma Aldrich) was
dissolved in 14.2 mL of 0.2M HCl. This solution was then added
drop-wise to the 25 grams of 0.5% Re/0.5% Sn/Al.sub.2O.sub.3
catalyst with proper mixing. Finally, the catalyst was dried at
110.degree. C. for 10 h under vacuum oven and then calcined under
air at 500.degree. C. for 3h. This method is also used in
preparation of Pt--Sn-- Re/Al.sub.2O.sub.3 catalysts containing
different amounts of Pt, Sn, and Re, such as 0.1 to 20% Pt (w/w),
0.1% to 20% Sn (w/w), 0.1% to 20% Re (w/w), and different
combinations thereof.
Example 3E: 0.5% Pt-0.5% Sn-0.5% Bi/Al.sub.2O.sub.3
[0512] Trimetallic Pt--Sn--Bi catalyst was prepared by sequential
incipient wetness impregnation method. Initially 0.2975 grams of
Bi(NO.sub.3).sub.3.2H.sub.2O was dissolved in 17.5 mL of de-ionized
water, and 0.5 mL of concentrated HNO.sub.3 was added to the above
solution to completely dissolve the metal precursor. This solution
was then added drop-wise to the 25 grams of Al.sub.2O.sub.3 support
with proper mixing. After that, the catalyst was dried at
110.degree. C. for 10 h under vacuum oven and then calcined under
air at 500.degree. C. for 3h. Then, 0.2436 grams of
SnCl.sub.2.2H.sub.2O was dissolved in 17.5 mL of de-ionized water.
Two drops of concentrated HCl was added to the above solution to
completely dissolve the metal precursor, and the solution was then
added drop-wise to the 25 grams of 0.5% Bi/Al.sub.2O.sub.3 catalyst
with proper mixing. After that, the catalyst was dried at
110.degree. C. for 10 h under vacuum oven and then calcined under
air at 500.degree. C. for 3h. In the next step, 3.3 grams of
H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma Aldrich) was
dissolved in 14.2 mL of 0.2M HCl. This solution was added drop-wise
to the 25 grams of 0.5% Sn/0.5% Bi/Al.sub.2O.sub.3 catalyst with
proper mixing. The catalyst was then dried at 110.degree. C. for 10
h under vacuum oven and calcined under air at 500.degree. C. for
3h. This method is also used in preparation of Pt--Sn--
Bi/Al.sub.2O.sub.3 catalysts containing different amounts of Pt,
Sn, and Bi, such as 0.1 to 20% Pt (w/w), 0.1% to 20% Sn (w/w), 0.1%
to 20% Bi (w/w), and different combinations thereof.
Example 3F: 0.5% Pt-0.5% Sn-0.5% Ba/Al.sub.2O.sub.3
[0513] Trimetallic Pt--Sn--Ba catalyst was prepared by sequential
incipient wetness impregnation method. Initially, 0.1846 grams of
Ba(NO.sub.3).sub.2(99.5%) was dissolved in 17.5 mL of de-ionized
water, and this solution was added drop-wise to the 25 grams of
Al.sub.2O.sub.3 support with proper mixing. After that, the
catalyst was dried at 110.degree. C. for 10h under vacuum oven and
then calcined under air at 500.degree. C. for 3h to produce 0.5%
Ba/Al.sub.2O.sub.3 catalyst. Then 0.2436 grams of
SnCl.sub.2.2H.sub.2O was dissolved in 17.5 mL of de-ionized water.
Two drops of concentrated HCl was added to this solution to
completely dissolve the metal precursor. This solution was added
drop-wise to the 25 grams of 0.5% Ba/Al.sub.2O.sub.3 catalyst with
proper mixing. After that, the catalyst was dried at 110.degree. C.
for 10 h under vacuum oven and then calcined under air at
500.degree. C. for 3h. In the next step, 3.3 grams of
H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma Aldrich) was
dissolved in 14.2 mL of 0.2M HCl was added. This solution was added
drop-wise to the 25 grams of 0.5% Sn/0.5% Ba/Al.sub.2O.sub.3
catalyst with proper mixing. Finally, the catalyst was dried at
110.degree. C. for 10 h under vacuum oven and then calcined under
air at 500.degree. C. for 3h. This method is also used in
preparation of Pt--Sn--Ba/Al.sub.2O.sub.3 catalysts containing
different amounts of Pt, Sn, and Ba, such as 0.1 to 20% Pt (w/w),
0.1% to 20% Sn (w/w), 0.1% to 20% Ba (w/w), and different
combinations thereof.
Example 4: Preparation of Acid-Treated Alumina Catalysts
Example 4A: 0.5% Pt/H.sub.3PO.sub.4-Al.sub.2O.sub.3Catalyst
[0514] In the first step, Al.sub.2O.sub.3 support was pretreated
with X % H.sub.3PO.sub.4 (e.g., X=2.5%, 5% and 10%) solution
prepared from 85% Phosphoric acid (H.sub.3PO.sub.4) solution. The
required amount of 85% H.sub.3PO.sub.4 was dissolved in appropriate
amount of water and added dropwise to 25 grams of Al.sub.2O.sub.3
support with proper mixing. After the addition was completed, the
H.sub.3PO.sub.4 treated Al.sub.2O.sub.3 support was kept at room
temperature for 3h. Then, the H.sub.3PO.sub.4--Al.sub.2O.sub.3
catalyst was dried at 110.degree. C. for 10 h in a vacuum oven and
calcined under air at 500.degree. C. for 3h. In the second step,
incipient wetness impregnation method used for the preparation of
Pt-modified catalyst. In the next step, 3.3 grams of
H.sub.2PtCl.sub.6xH.sub.2O solution (8%, Sigma Aldrich) was
dissolved in 14.2 mL of 0.2M HCl, and this solution was added
drop-wise to the 25 grams of X % H.sub.3PO.sub.4-Al.sub.2O.sub.3
catalyst with proper mixing. After the addition was completed, the
catalyst was dried at 110.degree. C. for 10 h in vacuum oven and
calcined under air at 500.degree. C. for 3h. This method was used
to prepare 0.5% Pt/2.5% H.sub.3PO.sub.4-Al.sub.2O.sub.3, 0.5% Pt/5%
H.sub.3PO.sub.4-Al.sub.2O.sub.3 and 0.5% Pt/10%
H.sub.3PO.sub.4-Al.sub.2O.sub.3 catalysts. This method is also used
in preparation of Pt/H.sub.3PO.sub.4-Al.sub.2O.sub.3 catalysts
containing different amounts of Pt, and H.sub.3PO.sub.4 such as 0.1
to 20% Pt (w/w), 0.1% to 20% H.sub.3PO.sub.4 (w/w), and different
combinations thereof.
Example 4B: 0.5% Pt/H.sub.3BO.sub.3-Al.sub.2O.sub.3Catalyst
[0515] In the first step, Al.sub.2O.sub.3 support was pretreated 5%
H.sub.3BO.sub.3 using Boric acid (H.sub.3BO.sub.3) solution. The
2.6368 grams of H.sub.3BO.sub.3 was dissolved in 34 mL of water and
then added drop-wise to the 25 grams of Al.sub.2O.sub.3 support
with proper mixing. After the addition was completed, the
H.sub.3BO.sub.3 treated Al.sub.2O.sub.3 support was kept at room
temperature for 3h. Then, the H.sub.3BO.sub.3--Al.sub.2O.sub.3
catalyst was dried at 110.degree. C. for 10 h in a vacuum oven and
calcined under air at 500.degree. C. for 3h. In the second step,
incipient wetness impregnation method used for the preparation of
Pt-modified catalyst. 3.3 grams of H.sub.2PtCl.sub.6xH.sub.2O
solution (8%, Sigma Aldrich) was dissolved in 14.2 mL of 0.2M HCl
and this solution was added drop-wise to the 25 grams of 5%
H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst with proper mixing After
the addition was completed, the catalyst was dried at 110.degree.
C. for 10h in vacuum oven and calcined under air at 500.degree. C.
for 3h. This method was used to prepare 0.5% Pt/5%
H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst. This method is also used
in preparation of Pt/H.sub.3BO.sub.3-- Al.sub.2O.sub.3 catalysts
containing different amounts of Pt, and H.sub.3BO.sub.3 such as 0.1
to 20% Pt (w/w), 0.1% to 20% H.sub.3BO.sub.3 (w/w), and different
combinations thereof.
Example 5
General Reaction Conditions for Catalytic Conversion of Ethanol to
Hydrocarbons
[0516] The general reaction conditions under which the feedstock
containing ethanol can be converted to hydrocarbons in a catalytic
reactor involves a temperature in the range of 300-400.degree. C.,
pressure in the range of 20-50 atm, gas flow (e.g., N.sub.2) at the
rate of 1.5-6 h.sup.-1 and Liquid Hourly Space Velocity (LHSV) of
2-4 h.sup.-1. The specific catalyst compositions, and reaction
conditions are recited in the descriptions of the FIGS. 18A-23C,
with corresponding product distribution shown in the respective
figures. A detailed compound composition breakdown is provided for
each product. Because of a slight compound characterization
variation, the complete hydrocarbon report for some products
displays minor differences in composition percentages.
Example 5A: Catalytic Conversion with HZSM-5
[0517] The biomass-derived ethanol was converted to hydrocarbons in
the presence of 2.3 g of HZSM-5 catalyst, at a temperature of
350.degree. C., pressure of 500 psig and volumetric linear flow
rate (LFR) of 0.125 mL/min. The process was carried out in a 3.7
cm.sup.3 reactor. FIG. 18A provides a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
this process. The graph shows the percentage amounts (vertical
axis) of aromatics, alkenes, alkanes and of oxygenates containing
C2-C18 hydrocarbons (horizontal axis) formed by the catalytic
conversion of ethanol. For example, the HZSM-5 catalyzed reaction
produced hydrocarbons of average carbon number 8.76, containing
about 94.02% aromatics, 0.44% alkenes, 3.38% alkanes and 0.03%
oxygenates, as determined by total ion chromatography peak area.
FIG. 18A-2 provides a complete hydrocarbon report of the product
described in FIG. 18A including a detailed breakdown of all the
compound types. FIG. 18B provides a graphical description of the
product distribution of aromatics, alkenes, alkanes and oxygenates
of various carbon content in the hydrocarbon mixture generated by
the catalytic processing of biomass-derived ethanol when the
biomass-derived ethanol is converted to hydrocarbons in the
presence of 0.5% Ru/HZSM-5 catalyst, at a temperature of
350.degree. C., pressure of 500 psig and volumetric linear flow
rate (LFR) of 0.125 mL/min. The resulting hydrocarbons had an
average carbon number of 8.57 and contained about 91.13% of
aromatics, 0.47% of alkenes, 5.87% of alkanes and 0.03% of
oxygenates, as determined by total ion chromatography peak area.
FIG. 18B-2 provides a complete hydrocarbon report of the product
described in FIG. 18B including a detailed breakdown of all the
compound types. FIGS. 18C and 18C-2 provide a graphical description
of the product distribution when the same reaction is run at a
volumetric linear flow rate (LFR) of 0.1875 mL/min. The resulting
hydrocarbons had an average carbon number of 7.78 and contained
about 69.08% of aromatics, 4.73% of alkenes, 22.94% of alkanes and
0.97% of oxygenates, as determined by total ion chromatography peak
area. FIG. 18C-2 provides a complete hydrocarbon report of the
product described in FIG. 18C including a detailed breakdown of all
the compound types.
Example 5B: Catalytic Conversion with 0.5% Pt-0.5%
Sn/Al.sub.2O.sub.3
[0518] Biomass-derived ethanol was converted to hydrocarbons in the
presence of 2.3 g of 0.5% Pt-0.5% Sn/Al.sub.2O.sub.3, at a
temperature of 350.degree. C., pressure of 500 psig and volumetric
linear flow rate (LFR) of 0.125 mL/min. The process was carried out
in a 3.7 cm.sup.3 reactor. FIG. 19A provides a graphical
description of the product distribution of aromatics, alkenes,
alkanes and oxygenates of various carbon content in the hydrocarbon
mixture generated by this process. The graph shows the percentage
amounts (vertical axis) of aromatics, alkenes, alkanes and of
oxygenates containing C2-C18 hydrocarbons (horizontal axis) formed
by the catalytic conversion of ethanol. For example, the 0.5%
Pt-0.5% Sn/Al.sub.2O.sub.3 catalyzed reaction produced hydrocarbons
of average carbon number 9.2, containing about 44.16% aromatics,
0.51% alkenes, 32.32% alkanes and 0.3% oxygenates, as determined by
total ion chromatography peak area. FIG. 19A-2 provides a complete
hydrocarbon report of the product described in FIG. 19A including a
detailed breakdown of all the compound types. FIG. 19B provides a
graphical description of the product distribution when the same
reaction was run at a volumetric linear flow rate (LFR) of 0.1875
mL/min. The resulting hydrocarbons had an average carbon number of
7.11 and contained about 25.59% of aromatics, 10.97% of alkenes,
53.03% of alkanes and 0.86% of oxygenates, as determined by total
ion chromatography peak area. FIG. 19B-2 provides a complete
hydrocarbon report of the product described in FIG. 19B including a
detailed breakdown of all the compound types.
Example 5C: Catalytic Conversion with 0.5% Pt-0.5%
Bi/Al.sub.2O.sub.3
[0519] Biomass-derived ethanol was converted to hydrocarbons in the
presence of 2.3 g of 0.5% Pt-0.5% Bi/Al.sub.2O.sub.3, at a
temperature of 350.degree. C., pressure of 500 psig and volumetric
linear flow rate (LFR) of 0.125 mL/min. The process was carried out
in a 3.7 cm.sup.3 reactor. FIG. 20 provides a graphical description
of the product distribution of aromatics, alkenes, alkanes and
oxygenates of various carbon content in the hydrocarbon mixture
generated by this process. The graph shows the percentage amounts
(vertical axis) of aromatics, alkenes, alkanes and of oxygenates
containing C2-C18 hydrocarbons (horizontal axis) formed by the
catalytic conversion of ethanol. For example, the 0.5% Pt-0.5%
Bi/Al.sub.2O.sub.3 catalyzed reaction produced hydrocarbons of
average carbon number 7.14, containing about 17.08% aromatics,
11.09% alkenes, 53.62% alkanes and 6.66% oxygenates, as determined
by total ion chromatography peak area. FIG. 20A provides a complete
hydrocarbon report of the product described in FIG. 20 including a
detailed breakdown of all the compound types.
Example 5D: Catalytic Conversion with 0.5% Pt-0.75%
Ba/Al.sub.2O.sub.3, and 0.5% Pt-1.0% Ba/Al.sub.2O.sub.3
[0520] Biomass-derived ethanol was converted to hydrocarbons in the
presence of 2.3 g of 0.5% Pt-0.75% Ba/Al.sub.2O.sub.3, at a
temperature of 350.degree. C., pressure of 500 psig and volumetric
linear flow rate (LFR) of 0.125 mL/min. The process was carried out
in a 3.7 cm.sup.3 reactor. FIG. 21A provides a graphical
description of the product distribution of aromatics, alkenes,
alkanes and oxygenates of various carbon content in the hydrocarbon
mixture generated by this process. The graph shows the percentage
amounts (vertical axis) of aromatics, alkenes, alkanes and of
oxygenates containing C2-C18 hydrocarbons (horizontal axis) formed
by the catalytic conversion of ethanol. For example, the 0.5%
Pt-0.75% Ba/Al.sub.2O.sub.3 catalyzed reaction produced
hydrocarbons of average carbon number 8.22, containing about 12.01%
aromatics, 4.97% alkenes, 61.88% alkanes and 15.70% oxygenates, as
determined by total ion chromatography peak area. FIG. 21A-2
provides a complete hydrocarbon report of the product described in
FIG. 21A including a detailed breakdown of all the compound types.
FIG. 21B provides a graphical description of the product
distribution when the same reaction was run with 0.5% Pt-1.0%
Ba/Al.sub.2O.sub.3 catalyst. The resulting hydrocarbons had an
average carbon number of 7.72 and contained about 7.87% of
aromatics, 4.05% of alkenes, 76.53% of alkanes and 9.19% of
oxygenates, as determined by total ion chromatography peak area.
FIG. 21B-2 provides a complete hydrocarbon report of the product
described in FIG. 21B including a detailed breakdown of all the
compound types.
Example 5E: Catalytic Conversion with 0.5% Pt-10%
H.sub.3PO.sub.4--Al.sub.2O.sub.3
[0521] Biomass-derived ethanol is converted to hydrocarbons in the
presence of 2.3 g of 0.5% Pt-10% H.sub.3PO.sub.4--Al.sub.2O.sub.3,
at a temperature of 350.degree. C., pressure of 300 psig and
volumetric linear flow rate (LFR) of 0.125 mL/min. The process was
carried out in a 3.7 cm.sup.3 reactor. FIG. 22A provides a
graphical description of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
hydrocarbon mixture generated by this process. The graph shows the
percentage amounts (vertical axis) of aromatics, alkenes, alkanes
and of oxygenates containing C2-C18 hydrocarbons (horizontal axis)
formed by the catalytic conversion of ethanol. For example, the
0.5% Pt-10% H.sub.3PO.sub.4--Al.sub.2O.sub.3 catalyzed reaction
produced hydrocarbons of average carbon number 8.4, containing
about 31.09% aromatics, 3.84% alkenes, 48.64% alkanes and 0.41%
oxygenates, as determined by total ion chromatography peak area.
FIG. 22A-2 provides a complete hydrocarbon report of the product
described in FIG. 22A including a detailed breakdown of all the
compound types. FIGS. 22B and 22B-2 provides a graphical
description of the product distribution when the same reaction was
run at a pressure of 500 psig. The resulting hydrocarbons had an
average carbon number of 9.66 and contained about 39.53% of
aromatics, 1.6% of alkenes, 45.10% of alkanes and 0.30% of
oxygenates, as determined by total ion chromatography peak area.
FIG. 22B-2 provides a complete hydrocarbon report of the product
described in FIG. 22B including a detailed breakdown of all the
compound types. FIG. 22C provides a graphical description of the
product distribution when the same reaction was run at a pressure
of 700 psig. The resulting hydrocarbons had an average carbon
number of 8.80 and contained about 30.43% of aromatics, 1.78% of
alkenes, 47.27% of alkanes and 1.04% of oxygenates, as determined
by total ion chromatography peak area. FIG. 22C-2 provides a
complete hydrocarbon report of the product described in FIG. 22C
including a detailed breakdown of all the compound types.
Example 5F: Catalytic Conversion with 0.5% Pt/5.0%
H.sub.3BO.sub.3--Al.sub.2O.sub.3
[0522] Biomass-derived ethanol is converted to hydrocarbons in the
presence of 2.3 g of 0.5% Pt/5.0% H.sub.3BO.sub.3--Al.sub.2O.sub.3,
at a temperature of 325.degree. C., pressure of 500 psig and
volumetric linear flow rate (LFR) of 0.125 mL/min. The process was
carried out in a 3.7 cm.sup.3 reactor. FIG. 23A provides a
graphical description of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
hydrocarbon mixture generated by this process. The graph shows the
percentage amounts (vertical axis) of aromatics, alkenes, alkanes
and of oxygenates containing C2-C18 hydrocarbons (horizontal axis)
formed by the catalytic conversion of ethanol. For example, the
0.5% Pt/5.0% H.sub.3BO.sub.3--Al.sub.2O.sub.3 catalyzed reaction
produced hydrocarbons of average carbon number 7.2, containing
about 4.67% aromatics, 0.95% alkenes, 91.91% alkanes and 0.05%
oxygenates, as determined by total ion chromatography peak area.
FIG. 23A-2 provides a complete hydrocarbon report of the product
described in FIG. 23A including a detailed breakdown of all the
compound types. FIGS. 23B, 23B-2, 23C, 23C-2, 23D, and 23D-2
provide a graphical description of the product distribution when
the same reaction was run at a temperature of 350.degree. C., and
at a pressure of 300 psig, 500 psig, and 700 psig, respectively.
When the reaction was run at a temperature of 350.degree. C., and
at a pressure of 300 psig, the resulting hydrocarbons had an
average carbon number of 7.7, and contained about 19.24% of
aromatics, 1.32% of alkenes, 73.01% of alkanes and 0.31% of
oxygenates, as determined by total ion chromatography peak area.
When the reaction was run at a temperature of 350.degree. C., and
at a pressure of 500 psig, the resulting hydrocarbons had an
average carbon number of 8.77, and contained about 19.35% of
aromatics, 0.24% of alkenes, 64.81% of alkanes and 4.93% of
oxygenates, as determined by total ion chromatography peak area.
When the reaction was run at a temperature of 350.degree. C., and
at a pressure of 700 psig, the resulting hydrocarbons had an
average carbon number of 8.17, and contained about 10.42% of
aromatics, 1.37% of alkenes, 81.65% of alkanes and 0.88% of
oxygenates, as determined by total ion chromatography peak area.
FIGS. 23B-2, 23C-2, and 23D-2 provide a complete hydrocarbon report
of the respective product described in FIGS. 23B, 23C, and 23D
including a detailed breakdown of all the compound types.
Example 5G: Catalytic Conversion with 0.5% Pt-0.5% Sn-0.5%
Bi/Al.sub.2O.sub.3
[0523] Biomass-derived ethanol was catalytically converted to
hydrocarbons in the presence of 2.3 g of 0.5% Pt-0.5% Sn-0.5%
Bi/Al.sub.2O.sub.3, at a temperature of 350.degree. C., pressure of
500 psig and volumetric linear flow rate (LFR) of 0.125 mL/min. The
process was carried out in a 3.7 cm.sup.3 reactor. FIG. 25 provides
a graphical description of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
hydrocarbon mixture generated by this process. The graph shows the
percentage amounts (vertical axis) of aromatics, alkenes, alkanes
and of oxygenates containing C2-C18 hydrocarbons (horizontal axis)
formed by the catalytic conversion of ethanol. The reaction
produced hydrocarbons of average carbon number 8.25, containing
about 30.51% aromatics, 5.29% alkenes, 39.35% alkanes and 3.43%
oxygenates, as determined by total ion chromatography peak area.
FIG. 25A provides a complete hydrocarbon report of the product
described in FIG. 25 including a detailed breakdown of all the
compound types.
Example 5H: Catalytic Conversion with 0.5% Pt-0.5% Sn-0.5%
Bi/Al.sub.2O.sub.3
[0524] Biomass-derived ethanol was catalytically converted to
hydrocarbons in the presence of 2.3 g of 0.5% Pt-0.5% Sn-0.5%
Re/Al.sub.2O.sub.3, at a temperature of 350.degree. C., pressure of
500 psig and volumetric linear flow rate (LFR) of 0.125 mL/min. The
process was carried out in a 3.7 cm.sup.3 reactor. FIG. 26 provides
a graphical description of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
hydrocarbon mixture generated by this reaction. The graph shows the
percentage amounts (vertical axis) of aromatics, alkenes, alkanes
and of oxygenates containing C2-C18 hydrocarbons (horizontal axis)
formed by the catalytic conversion of ethanol. The reaction
produced hydrocarbons of average carbon number 8.19, containing
about 31.47% aromatics, 14.34% alkenes, 31.87% alkanes and 1.53%
oxygenates, as determined by total ion chromatography peak area.
FIG. 26A provides a complete hydrocarbon report of the product
described in FIG. 26 including a detailed breakdown of all the
compound types.
Superior Quality Unblended Cellulosic-Biomass Derived
Gasoline--without Fractional Distillation
[0525] Provided herein is an unblended cellulosic-biomass derived
gasoline of high research octane number, and a method for producing
the same. The unblended cellulosic-biomass derived gasoline is a
liquid produced by the process described herein without further
mixing or blending. And, in some embodiments, the unblended
cellulosic-biomass derived gasoline comprises a liquid produced by
the processes described herein that has been further distilled in
the gasoline distillation with range from 900 F to 4100 F. In one
embodiment, the unblended cellulosic-biomass derived gasoline is
produced by catalytic processing of the cellulosic-biomass or a
product derived therefrom. In one embodiment, the research octane
number of the unblended cellulosic-biomass derived gasoline is
greater than about 87, as determined by ASTM D2699. For example,
the unblended gasoline can have a research octane number (RON) of
greater than about 87, about 90, about 91, about 92, about 93,
about 94, about 95, about 96, about 97, about 98, or about 99. This
application refers to a number of ASTM methods or standards,
including ASTM D2699 (approved Oct. 1, 2017), ASTM D2700 (approved
Dec. 1, 2017), ASTM D5191 (approved Oct. 1, 2015), ASTM D4809
(approved May 1, 2013), ASTM D4814-X1.4 (approved Jan. 1, 2018),
and ASTM D4052 (approved Dec. 1, 2016), all of which are
incorporated here by reference. The catalyst used in this process
can be any of the catalysts disclosed herein, including an
alumina-based catalyst and/or a zeolite-based catalyst. In some
embodiments, the catalyst is a mono-metallic catalyst, bi-metallic
catalyst, or tri-metallic catalyst. In some embodiments, the
catalysts contain metals selected from the group consisting of Pt,
Pd, Sn, Re, Rh, Bi, Ba, Ti, Ni, and any combinations thereof.
[0526] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a relatively high motor octane number (MON) of
greater than about 80 as determined by ASTM D2700 (approved Dec. 1,
2017). For example, the MON can be greater than about 80, about 81,
about 82, about 83, about 84, about 85, about 86, about 87, about
88, about 89, about 90, or about 92.
[0527] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a dry vapor pressure equivalent, EPA that is
greater than about 4 psi, as determined by ASTM D5191 (approved
Oct. 1, 2015). For example, the dry vapor pressure equivalent, EPA
can be greater than about 4 psi, about 5 psi, about 6 psi, about 7
psi, about 8 psi, about 9 psi, or about 10 psi.
[0528] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a relatively high energy content such as a
gross heat of combustion, as determined by ASTM D4809 (approved May
1, 2013). For example, the heat of combustion can be greater about
120,0000 Btu/gal, about 121,000 Btu/gal, about 122,000 Btu/gal,
about 123,000 Btu/gal, about 124,000 Btu/gal, about 125,000
Btu/gal, about 126,000 Btu/gal, or about 128,000 Btu/gal.
[0529] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a superior antiknock index or octane rating
((RON+MON)/2), as determined by ASTM D4814-X1.4 (approved Jan. 1,
2018). For example, the antiknock index can be greater than about
85, about 86, about 87, about 88, about 89, about 90, about 91,
about 92, about 93, about 94, or about 95.
[0530] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have an API Gravity at 60.degree. F. of
greater than about 40.degree. API, as determined by ASTM D4052
(approved Dec. 1, 2016), e.g., greater than about 41.degree. API,
about 42.degree. API, about 43.degree. API, about 44.degree. API,
about 45.degree. API, about 46.degree. API, about 47.degree. API,
about 48.degree. API, about 49.degree. API, about 50.degree. API,
about 51.degree. API, about 52.degree. API, about 53.degree. API,
about 54.degree. API, about 55.degree. API, about 56.degree. API,
about 57.degree. API, about 58.degree. API, about 59.degree. API,
or about 60.degree. API.
[0531] The unblended cellulosic-biomass derived gasoline described
herein can have any combination of RON, MON, dry vapor pressure
equivalent, gross heat of combustion, antiknock index, and API
Gravity at 60.degree. F. discussed above. For example, in one
embodiment, the unblended cellulosic-biomass derived gasoline has
an RON of greater than 88, a MON of greater than 86, an antiknock
index greater than 87, a dry vapor pressure equivalent, EPA of 6
psi, an API gravity at 60.degree. F. of between about 40 and 65,
and a gross heat of combustion of between about 120,000 Btu/gal and
130,000 Btu/gal.
[0532] In one embodiment, the unblended cellulosic-biomass derived
gasoline is produced by catalytically processing a
cellulosic-biomass derived ethanol using the methods and the
catalysts described herein. The cellulosic-biomass may be further
pretreated with electron beam radiation. In some embodiments, the
irradiating (with any radiation source or a combination of sources)
is performed until the cellulosic-biomass receives a dose of at
least 0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, at
least 5.0 Mrad, or at least 10.0 Mrad. In some embodiments, the
irradiating is performed until the material receives a dose of
between 1.0 Mrad and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad.
In some embodiments, the irradiating is performed at a dose rate of
between 5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0
kilorads/hour or between 50.0 and 350.0 kilorads/hours.
[0533] The unblended cellulosic-biomass derived gasoline produced
by this invention can be a mixture of different hydrocarbons, such
as linear or branched, mono-, and di-substituted C.sub.7-C.sub.16
alkanes, one or more of which is derived from cellulosic-biomass.
It may also contain olefins, substituted or unsubstituted
cycloalkanes (such as cyclopentanes, cyclohexanes), aromatics (such
as benzene, toluene, naphthalenes), mono-substituted aromatics
(such as methyl benzene), di-substituted aromatics (such as
xylenes), and multi-substituted aromatics (such as
trimethylbenzenes), one or more of which is derived from the
cellulosic-biomass.
[0534] In some instances, the unblended cellulosic-biomass derived
gasoline contains less than about 5 percent by weight benzene, such
as less than 4.5, 4.0, 3.5, 3.0, 2.5, 2.0, 1.5, or even less than
1.0 percent by weight, e.g., less than 0.9, 0.8, 0.7, 0.6, 0.5,
0.4, 0.3, or even less than 0.25 percent by weight, e.g., less than
0.2, 0.15, 0.1 or even less than 0.05 percent by weight. In
particular, the methods and catalysts can, for example, if desired,
give the low benzene content directly, without active removal or
separation, such as by distillation of the benzene from other
components. Low concentrations of benzene can be useful in
jurisdictions, such as the United States, that strictly limit its
concentration in gasoline. In the United States, the USEPA sets a
limit of benzene to be less than 1.3 percent by weight in
gasoline.
[0535] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein, such as a high-octane gasoline
(HOG) contains a high aromatics content. For example, the unblended
cellulosic-biomass derived gasoline may contain greater than about
25% (w/w), about 30% (w/w), about 35% (w/w), about 40% (w/w), about
45% (w/w), about 50% (w/w), about 55% (w/w), about 60% (w/w), about
65% (w/w), about 70% (w/w), about 75% (w/w), about 80% (w/w), about
285% (w/w), about 90% (w/w) of aromatic hydrocarbons. In some
instances, the aromatics can include toluene and xylenes, for
example, as o, m- or para-xylene. In some instances, the
predominant aromatics produced are toluene and xylenes, making up
more than about 60 percent by weight of the aromatics produced, for
example, greater than 65, 66, 67, 68, 69, 70, or 72 percent by
weight or even greater, such as greater than about 75 percent by
weight toluene and xylenes. In these instances, these materials can
be distilled to produce pure toluene and xylenes, which can,
respectively, be used to produce compounds such as toluene
diisocyanate and isomers of terephthalic acid.
[0536] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein, such as a HOG can have
relatively low amount of alkanes. For example, the gasoline may
contain less than about 50% (w/w), about 40% (w/w), about 30%
(w/w), about 20% (w/w), about 10% (w/w), about 5% (w/w), about 2%
(w/w), or about 1% (w/w) of alkanes. In some embodiments, the
unblended cellulosic-biomass derived gasoline described herein,
such as a HOG have a ratio of alkanes:aromatics of between about
1:10 and 1:100, such as between 1:10 and 1:50, or between 1:15 and
1:40 or between about 1:15 and 1:25.
[0537] Note that, in some instances, adjusting the methods and/or
the catalysts used in the catalytical process described herein may
directly change the chemical properties of the resulting unblended
cellulosic-biomass derived gasoline, and therefore, enabling the
process to obtain an ideal concentration of hydrocarbons without
the need for further dilution, distillation, or blending.
[0538] In some embodiments, the unblended cellulosic-biomass
derived gasoline of such mixtures can be used directly as
transportation fuels, as blending components in transportation
fuels, such as commercial gasoline.
[0539] In one embodiment, the methods and catalysts can, for
example, if needed, produce desired fuels, e.g., motor fuels,
directly without upgrading or downgrading the fuel, such as by
blending. For example, in some instances, the unblended gasoline
produced from reactors can be used in fuel tanks of transportation
vehicles without any additional treatment. The gasolines can be,
for example, a regular octane grade, a mid-octane grade or a
high-octane grade gasoline. In other instances, the gasolines
produced from reactors can be used directly in fuel tanks of
transportation vehicles only after filtering the fuel to remove
particulates, and/or after distillation to remove low boiling
fractions and/or high boiling fractions. In still other
embodiments, the unblended gasolines obtained from the reactors
described herein, can form a blend stock as obtained or after some
purification. For example, in some instances, the unblended
gasolines obtained from the reactors described herein can be a
high-octane blending component, such as having a research octane
number of greater than about 87, about 90, about 91, about 92,
about 93, about 94, about 95, about 96, about 97, about 98, or
about 99.
[0540] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has a boiling point range of
about 35.degree. C. to 200.degree. C. In some embodiments, less
than about 10%, about 9%, about 8%, about 7%, about 6%, about 5%,
about 4%, about 3%, about 2%, or about 1% of the fraction of the
unblended cellulosic-biomass derived gasoline boils at a
temperature above 160.degree. C.
[0541] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has an oxygenate level of less
than about 0.5% (wt./wt.), about 0.4% (wt./wt.), about 0.25%
(wt./wt.), or about 0.1% (wt./wt.). As used herein, the term
"oxygenates" is defined to include oxygen containing organic
compounds such as alcohols, ethers, carbonyl compounds (aldehydes,
ketones, carboxylic acids, carbonates, and the like).
Representative oxygenates include, but are not necessarily limited
to, lower straight chain or branched aliphatic alcohols, their
unsaturated counterparts. Examples include but are not necessarily
limited to: methanol; ethanol; n-propanol; isopropanol; C4-C10
alcohols; methyl ethyl ether; dimethyl ether; diethyl ether;
di-isopropyl ether; methyl mercaptan; methyl formate, methyl
acetate, formaldehyde; di-methyl carbonate; trimethyl orthoformate,
and dimethyl ketone. Oxygenates such as acetaldehyde and acetone
can be corrosive and can damage gaskets in engine components. They
can also make the fuel hygroscopic, allowing it to absorb water,
thereby impacting the quality of gasoline. So, in some embodiments
having low oxygenate content in gasoline may be desirable.
[0542] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has a naphthalene content of less
than about 0.5% (wt./wt.), about 0.4% (wt./wt.), about 0.25%
(wt./wt.), or about 0.1% (wt./wt.). Naphthalenes are toxic air
pollutants, add unfavorable smell to gasoline and are recognized as
possible human carcinogens. So, in some embodiments having low
naphthalene content in gasoline may be desirable.
[0543] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has an aromatic content of
greater than about 75% (wt./wt.), about 76% (wt./wt.), about 77%
(wt./wt.), about 78% (wt./wt.), about 79% (wt./wt.), about 80%
(wt./wt.), about 85% (wt./wt.).
Examples
[0544] A graphical depiction of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in a high-octane hydrocarbon distillate or high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein is shown in FIG. 27. The
product distribution shows a significantly high amount of aromatic
components. Based on the total known components, the HOG contained
about 81.17% of aromatic hydrocarbons, about 5.57% of alkenes,
about 9.77% of alkanes, and about 0.28% of oxygenated compounds
(wt./wt.). FIG. 27 also provides a detailed breakdown of all the
detectable compounds in the composition.
[0545] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in a low-octane hydrocarbon distillate or low-octane
gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein is shown in FIG. 28. Based
on the total known components, the LOG contained about 35.75% of
aromatic hydrocarbons, about 7.53% of alkenes, about 47.20% of
alkanes, and about 1.44% of oxygenated compounds (wt./wt.). FIG. 28
also provides a detailed breakdown of all the detectable compounds
in the composition.
[0546] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C1, which contains Trufuel.RTM., a commercially
available premixed high-octane ethanol-free fuel, is shown in FIG.
29. Based on the total known components, Trufuel.RTM. contained
about 33.13% of aromatic hydrocarbons, about 0.01% of alkenes,
about 59.25% of alkanes, and about 0.33% of oxygenated compounds
(wt./wt.). FIG. 29 also provides a detailed breakdown of all the
detectable compounds in sample C1.
[0547] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C2, which is a mixture of about 50% (v/v) of a
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and about 50% (v/v) of
Trufuel.RTM. is shown in FIG. 30. Based on the total known
components, it contained about 51.32% of aromatic hydrocarbons,
about 8.25% of alkenes, about 33.36% of alkanes, and about 1.45% of
oxygenated compounds (wt./wt.). FIG. 30 also provides a detailed
breakdown of all the detectable compounds in sample C2.
[0548] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C3, which is a mixture of about 85% (v/v) of
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and about 15% (v/v) of
Trufuel.RTM. is shown in FIG. 31. Based on the total known
components, it contained about 65.93% of aromatic hydrocarbons,
about 8.31% of alkenes, about 21.70% of alkanes, and about 0.30% of
oxygenated compounds (wt./wt.). FIG. 31 also provides a detailed
breakdown of all the detectable compounds in sample C3.
[0549] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C4, which is a mixture of about 70% (v/v) of
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and about 30% (v/v) of
low-octane gasoline (LOG), generated by the catalytic processing of
biomass-derived ethanol described herein is shown in FIG. 32. Based
on the total known components, it contained about 66.37% of
aromatic hydrocarbons, about 8.43% of alkenes, about 16.70% of
alkanes, and about 3.57% of oxygenated compounds (wt./wt.). FIG. 32
also provides a detailed breakdown of all the detectable compounds
in sample C4.
[0550] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C5, which is a mixture of about 65% (v/v) of
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, about 25% (v/v) of
low-octane gasoline (LOG), generated by the catalytic processing of
biomass-derived ethanol described herein, and about 10% of
anhydrous ethanol derived from cellulosic-biomass is shown in FIG.
33. Based on the total known components, it contained about 65.27%
of aromatic hydrocarbons, about 8.37% of alkenes, about 16.88% of
alkanes, and about 4.40% of oxygenated compounds (wt./wt.). FIG. 33
also provides a detailed breakdown of all the detectable compounds
in sample C5.
[0551] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample C6, which is a mixture of about 90% (v/v) of
high-octane gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and about 10% of
anhydrous ethanol derived from cellulosic-biomass, is shown in FIG.
34. Based on the total known components, it contained about 75.96%
of aromatic hydrocarbons, about 4.98% of alkenes, about 12.31% of
alkanes, and about 3.91% of oxygenated compounds (wt./wt.). FIG. 34
also provides a detailed breakdown of all the detectable compounds
in sample C6.
[0552] FIG. 35 provides the results of analyzing samples of blends
of high-octane gasoline of samples C1-C6, described above. The API
Gravity @ 60.degree. F. is measured according to ASTM D4052, the
Dry Vapor Pressure Equivalent (DVPE) EPA is measured according to
ASTM D5191-13, the gross heat of combustion is measured according
to ASTM D4809, the research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, and the antiknock index or octane rating
((RON+MON)/2) is measured according to D4814-X1.4. The data shows
that blending the gasolines produced by the processes described
herein does not significantly alter the RON, MON, gross heat of
combustion and antiknock index of the blend. This demonstrates that
the unblended cellulosic-biomass derived gasolines, in particular
the HOGs have a high octane rating similar to that of Trufuel.RTM..
In fact, sample C6, which contains only 90% of HOG produced by the
processes described herein, and 10% anhydrous cellulosic ethanol
has a high RON of 101.3, MON of 89.2, antiknock index of 95.2, and
gross heat of combustion of 128,832 BTU/gal.
[0553] FIG. 36 provides the results of analyzing samples of blends
of high-octane gasoline. Sample B1 is Trufuel.RTM.; sample B2 is a
mixture of 5% (v/v) of high-octane gasoline (HOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 95% (v/v) of Trufuel.RTM.; sample B3 is a mixture of 10% (v/v)
of high-octane gasoline (HOG) generated by the catalytic processing
of biomass-derived ethanol described herein, and 90% (v/v) of
Trufuel.RTM.; sample B4 is a mixture of 20% (v/v) of high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and 80% (v/v) of
Trufuel.RTM.; sample B5 is a mixture of 20% (v/v) of high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein, 75% (v/v) of
Trufuel.RTM., and 5% anhydrous ethanol derived from
cellulosic-biomass. The Dry Vapor Pressure Equivalent (DVPE) EPA is
measured according to ASTM D5191, the gross heat of combustion is
measured according to ASTM D4809, the research octane number (RON)
is measured according to ASTM D2699, the motor octane number (MON)
is measured according to ASTM D2700, and the antiknock index or
octane rating ((RON+MON)/2) is measured according to D4814-X1.4.
The data shows that blending the HOGs produced by the processes
described herein does not significantly alter the RON, MON, gross
heat of combustion and antiknock index of the blend. This
demonstrates that the unblended cellulosic-biomass derived
gasolines, in particular the HOGs, have a high octane rating
similar to that of Trufuel.RTM.. In fact, sample B5, which contains
the greatest amount of HOG among the studied samples (20% (v/v))
has a high RON of 100, MON of 91.2, antiknock index of 95.6, and
gross heat of combustion of 124,355 BTU/gal.
[0554] FIG. 37 provides the results of analyzing samples of blends
of low-octane gasoline. Sample 1 is Trufuel.RTM., a commercially
available premixed high-octane ethanol-free fuel; sample 2 is a
mixture of 5% (v/v) of low-octane gasoline (LOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 95% (v/v) of Trufuel.RTM.; sample 3 is a mixture of 10% (v/v)
of low-octane gasoline (LOG) generated by the catalytic processing
of biomass-derived ethanol described herein, and 90% (v/v) of
Trufuel.RTM.; sample 4 is a mixture of 20% (v/v) of low-octane
gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein, and 80% (v/v) of
Trufuel.RTM.; sample 5 is a mixture of 20% (v/v) of low-octane
gasoline (LOG) generated by the catalytic processing of
biomass-derived ethanol described herein, 75% (v/v) of
Trufuel.RTM., and 5% anhydrous ethanol derived from
cellulosic-biomass. The research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, and the antiknock index or octane rating
((RON+MON)/2) is measured according to D4814-X1.4.
A Method of Producing Fuel with Reduced Global Warming Potential
(GWP)
[0555] Provided herein is a method of producing fuel comprising:
receiving harvested cellulosic-biomass; treating the
cellulosic-biomass in a facility with an electron beam sufficient
to reduce its recalcitrance; saccharifying the
recalcitrance-reduced biomass to produce sugars and unsaccharified
biomass; fermenting the sugars to produce fuel; combusting the fuel
in a vehicle; generating heat and power from the unsaccharified
biomass in the facility, and using the remaining unprocessed
unsaccharified biomass as animal feed; wherein the method has a
Global Warming Potential (GWP) in gCO2 eq/MJ at least about 25%
less in comparison to a fuel generation process from starch-derived
ethanol, sugar-derived ethanol or conventional gasoline.
[0556] In some embodiments, the method further comprises
transporting the cellulosic-biomass to a facility. In some
embodiments, the method further comprises transporting the fuel to
a blending point and a point of use. In one embodiment, the fuel
produced by this method is ethanol. In some embodiments, the
starch-derived ethanol is obtained from corn. In some embodiments,
the sugar-derived ethanol is obtained from sugar. The
cellulosic-biomass used in the method described herein can be corn
cobs, soybean stover, corn stover, rice straw, rice hulls, barley
straw, corn cobs, wheat straw, canola straw, rice straw, oat straw,
oat hulls, corn fiber, recycled wood pulp fiber, sawdust, hardwood,
for example aspen wood and sawdust, softwood, or a combination
thereof.
[0557] In some embodiments, the method for producing fuel described
herein reduces the Global Warming Potential (GWP) in gCO.sub.2
eq/MJ by at least about 5%, about 10%, about 20%, about 25%, about
30%, about 35%, about 40%, about 45%, about 50%, about 55%, about
60%, about 65%, about 70%, about 75%, or about 80% in comparison to
a fuel generation process from corn ethanol, sugarcane ethanol or
conventional gasoline.
[0558] A Life Cycle Assessment (LCA) was conducted to evaluate the
Global Warming Potential (GWP) of the ethanol derived from
cellulosic-biomass (for, example corn stover) by the processes
described herein as compared to US corn grain ethanol, Brazilian
sugarcane ethanol, and US conventional gasoline in fuel blends
including E100 (98.5% ethanol with 2.5% gasoline for denaturing
purposes as required by the law), E10 (10% ethanol), E85 (85%
ethanol), and conventional gasoline. Regulatory frameworks, such as
the Renewable Fuels Standard (RFS2) and California Low Carbon Fuel
Standard (CA LCFS) focus primarily on GWP and are a significant
economy driver of the adoption of cellulosic ethanol. The GWP was
assessed using the Intergovernmental Panel on Climate Change's
(IPCC) Fifth Assessment Report (AR5) 100-year time-scale excluding
biogenic carbon method.
[0559] The LCA was conducted from cradle-to-grave, which included
the upstream production of corn stover as a feedstock for the
processes described herein as well as the production of all other
inputs to the process (e.g., natural gas, electricity, and
chemicals) as well as the downstream combustion of the fuel in an
average US passenger car. This ethanol production results in a
biomass solid co-product that can be burned in a Combined Heat and
Power (CHP) facility to produce on-site heat and electricity that
satisfies most of the facility's needs. The remaining biomass
solids can be sold locally as an animal feed which displaces corn
and soy in the diets of livestock.
[0560] FIG. 39 provides a diagram of the process for generating
ethanol from cellulosic-biomass from cradle-to-grave, which formed
the basis of the LCA analysis. The process begins with production
of cellulosic feedstock and ends with combustion of fuel. The
specific phases of the fuel life cycle include: [0561] Production
and harvesting of cellulosic-biomass [0562] Transportation of
biomass to the processing facility [0563] Pretreatment and enzyme
treatment of biomass to produce saccharified sugars [0564]
Fermentation of sugar to produce ethanol [0565] Distillation of
ethanol fuel to remove water [0566] Denaturation of ethanol to
produce fuel-grade ethanol [0567] On-site combined heat and power
production [0568] Transportation and distribution of fuel-grade
ethanol to blending and point of use [0569] Combustion of fuel in a
passenger vehicle In addition, the above-described process uses a
Combined Heat and Power (CHP) facility on-site. The CHP combusts
the biomass solid co-product of the ethanol production. This heat
and energy generated by combusting the biomass solids provides heat
and power to other portions of the process. The remaining biomass
solids are sold as an animal feed co-product. The transportation
distance for co-product feed is 60 miles (97 km) from the facility
based on the density of animal production in the region (USDA,
2017).
[0570] The key phases of production, transportation, and
distribution of the comparative corn grain ethanol, sugarcane
ethanol, and gasoline fuels mirror Xyleco fuel production. Modeling
for all systems in this study were conducted in the LCA software
GaBi ts, developed by thinkstep
(http://www.gabi-software.com/america/index/). The comparative fuel
dataset used for ethanol derived from corn is thinkstep USLCI
(2013-2017), for ethanol derived from sugarcane is ecoinvent v3.3
(2015), and for regular gasoline mix is thinkstep (2013-2017). The
average distance from refineries to filing station in the US is 93
miles (150 km), based on GaBi data documentation for gasoline,
therefore, this distance has been applied to all fuels to maintain
consistency of system boundaries. Combustion for all fuels is
assumed in the same passenger vehicle with the same fuel efficiency
in miles per gallon with adjustment made for the difference in
energy density between ethanol and gasoline.
[0571] The GWP analysis resulting from the above-described
calculation method is shown in FIG. 38. It provides the Global
Warming Potential (GWP) (in gCO.sub.2 eq/MJ) of fuel blends
containing ethanol generated from cellulosic-biomass by the
processes described herein in comparison with fuel blends
containing US corn grain ethanol, Brazilian sugarcane ethanol and
US conventional gasoline. Fuel blends of 100% ethanol (E100) (98.5%
ethanol with 2.5% gasoline for denaturing purposes as required by
the law), 10% ethanol (E10), 85% ethanol (E85), and conventional
gasoline were compared.
[0572] As shown in FIG. 38, the ethanol produced by the processes
described herein have a lower GWP by about 77% (for E100), about
62% (for E85), and about 5% (for E10) in comparison to corn grain
ethanol. Similarly, the ethanol produced by the processes described
herein lower the GWP by about 40% (for E100), about 25% (for E85),
and about 2% (for E10) in comparison to sugarcane ethanol.
Additionally, the ethanol produced by the processes described
herein lower the GWP by about 83% (for E100), about 71% (for E85),
and about 10% (for E10) in comparison to regular gasoline.
Superior Quality Unblended Cellulosic-Biomass Derived
Gasoline--with Fractional Distillation
[0573] Provided herein is an unblended cellulosic-biomass derived
gasoline of high research octane number, and a method for producing
the same. The unblended cellulosic-biomass derived gasoline is a
liquid produced by the process described herein without further
mixing or blending with substance not produced by the process
described herein. In some instances, the unblended
cellulosic-biomass derived gasoline includes a mix of liquid
fractions produced by one or more processes described herein such
as ethanols that do not get catalytically converted to the
unblended cellulosic-biomass derived gasoline. And, in some
embodiments, the unblended cellulosic-biomass derived gasoline
comprises a liquid produced by the processes described herein that
has been further distilled in the gasoline distillation with range
from 900 F to 4100 F. In one embodiment, the unblended
cellulosic-biomass derived gasoline is produced by catalytic
processing of the cellulosic-biomass or a product derived
therefrom. In one embodiment, the research octane number of the
unblended cellulosic-biomass derived gasoline is greater than about
60, as determined by ASTM D2699. For example, the unblended
gasoline can have a research octane number (RON) of greater than
about 87, about 90, about 91, about 92, about 93, about 94, about
95, about 96, about 97, about 98, or about 99. This application
refers to a number of ASTM methods or standards, including ASTM
D2699 (approved Oct. 1, 2017), ASTM D2700 (approved Dec. 1, 2017),
ASTM D5191 (approved Oct. 1, 2015), ASTM D4809 (approved May 1,
2013), ASTM D4814-X1.4 (approved Jan. 1, 2018), and ASTM D4052
(approved Dec. 1, 2016), ASTM D7039 (approved Jul. 1, 2015), ASTM
D3606 (approved Dec. 1, 2017), ASTM D1296 (approved Jul. 1, 2012),
ASTM E1064 (approved Apr. 1, 2016), ASTM D130 (approved Nov. 1,
2012), ASTM D4814-A1 (approved Jan. 1, 2018), all of which are
incorporated here by reference. The catalyst used in this process
can be any of the catalysts disclosed herein, including an
alumina-based catalyst and/or a zeolite-based catalyst. In some
embodiments, the catalyst is a mono-metallic catalyst, bi-metallic
catalyst, or tri-metallic catalyst. In some embodiments, the
catalysts contain metals selected from the group consisting of Pt,
Pd, Sn, Re, Rh, Bi, Ba, Ti, Ni, and any combinations thereof.
[0574] In some embodiments, the unblended cellulosic-biomass
derived gasoline may contain a mixture of different liquid
fractions produced by the process described herein. In some
embodiments, the fractions are separated based on their boiling
range. For instance, in some embodiments, the unblended
cellulosic-biomass derived gasoline may have a mix percentage of
fractions with boiling ranges below 35.degree. C. ("low boiling
range"), with boiling range between 35.degree. C. to about
200.degree. C. ("mid boiling range"), and with boiling range above
200.degree. C. ("high boling range"). In some embodiments, the low,
mid and high boiling ranges may be based on different temperature
ranges.
[0575] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a relatively high motor octane number (MON) of
greater than about 80 as determined by ASTM D2700 (approved Dec. 1,
2017). For example, the MON can be greater than about 80, about 81,
about 82, about 83, about 84, about 85, about 86, about 87, about
88, about 89, about 90, or about 92.
[0576] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have an API Gravity at 60.degree. F. of
greater than about 40.degree. API, as determined by ASTM D4052
(approved Dec. 1, 2016), e.g., greater than about 41.degree. API,
about 42.degree. API, about 43.degree. API, about 44.degree. API,
about 45.degree. API, about 46.degree. API, about 47.degree. API,
about 48.degree. API, about 49.degree. API, about 50.degree. API,
about 51.degree. API, about 52.degree. API, about 53.degree. API,
about 54.degree. API, about 55.degree. API, about 56.degree. API,
about 57.degree. API, about 58.degree. API, about 59.degree. API,
or about 60.degree. API. In some embodiments, the API Gravity at
60.degree. F. is between about 45 and 68.degree. API, such as
between about 48 and 65, or 50 and 62.degree. API.
[0577] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have a sulfur content of less than about 3.2
mg/kg, as determined by ASTM D7039, e.g., less than about 3.0
mg/kg, about 2.5 mg/kg, about 2.0 mg/kg, about 1.5 mg/kg, or about
1.0 mg/kg.
[0578] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have a benzene level of less than about 1.0
vol. %, as determined by ASTM D3606, e.g., less than about 0.9 vol.
%, about 0.8 vol. %, about 0.7 vol. %, about 0.6 vol. %, about 0.5
vol. %, about 0.4 vol. %, about 0.3 vol. %, or about 0.2 vol.
%.
[0579] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have either characteristic or noncharateristic
odor as determined by ASTM D1296, but not foul.
[0580] In some embodiments, the unblended cellulosic-biomass
derived gasoline may have a water content less than about 750 ppm
by weight, as determined by ASTM D1064, e.g., less than about 500
mg/kg, about 400 mg/kg, about 300 mg/kg, about 250 mg/kg, or about
100 mg/kg.
[0581] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a dry vapor pressure equivalent, EPA that is
greater than about 4 psi, as determined by ASTM D5191 (approved
Oct. 1, 2015). For example, the dry vapor pressure equivalent, EPA
can be greater than about 4 psi, about 5 psi, about 6 psi, about 7
psi, about 8 psi, about 9 psi, about 10 psi, or about 11 psi.
[0582] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a relatively high energy content such as a
gross heat of combustion, as determined by ASTM D4809 (approved May
1, 2013). For example, the heat of combustion can be greater about
120,0000 Btu/gal, about 121,000 Btu/gal, about 122,000 Btu/gal,
about 123,000 Btu/gal, about 124,000 Btu/gal, about 125,000
Btu/gal, about 126,000 Btu/gal, or about 128,000 Btu/gal.
[0583] In some embodiments, the unblended cellulosic-biomass
derived gasoline has copper strip corrosion of 1 or less, as
determined by ASTM D130. For example, 1a or 1b.
[0584] In some embodiments, the unblended cellulosic-biomass
derived gasoline has silver strip corrosion of 1 or less, as
determined by ASTM D4818-A1 (approved Jan. 1, 2018). For example, 1
or 0.
[0585] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a superior antiknock index or octane rating
((RON+MON)/2), as determined by ASTM D4814-X1.4 (approved Jan. 1,
2018). For example, the antiknock index can be greater than about
85, about 86, about 87, about 88, about 89, about 90, about 91,
about 92, about 93, about 94, or about 95.
[0586] The unblended cellulosic-biomass derived gasoline described
herein can have any combination of RON, MON, API Gravity at
60.degree. F., sulfur content, benzene level, odor, water content,
dry vapor pressure equivalent, gross heat of combustion, copper
corrosion level, silver corrosion level, and antiknock index
discussed above. For example, in one embodiment, the unblended
cellulosic-biomass derived gasoline has an RON of greater than 97,
a MON of greater than 85, an antiknock index greater than 91, an
API gravity at 60.degree. F. of between about 40 and 65, a sulfur
content less than 3.2 mg/kg, a benzene level less than about 0.7
vol. %, a noncharacteristic odor, a water content less than 250
mg/kg, dry vapor pressure equivalent, EPA of 10.87 psi, a gross
heat of combustion of between about 120,000 Btu/gal and 130,000
Btu/gal, a copper strip corrosion of 1a, a silver strip corrosion
of 0, and an antiknock index of 91.4.
[0587] In one embodiment, the unblended cellulosic-biomass derived
gasoline is produced by catalytically processing a
cellulosic-biomass derived ethanol using the methods and the
catalysts described herein. The cellulosic-biomass may be further
pretreated with electron beam radiation. In some embodiments, the
irradiating (with any radiation source or a combination of sources)
is performed until the cellulosic-biomass receives a dose of at
least 0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, at
least 5.0 Mrad, or at least 10.0 Mrad. In some embodiments, the
irradiating is performed until the material receives a dose of
between 1.0 Mrad and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad.
In some embodiments, the irradiating is performed at a dose rate of
between 5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0
kilorads/hour or between 50.0 and 350.0 kilorads/hours.
[0588] The unblended cellulosic-biomass derived gasoline produced
by this invention can be a mixture of different hydrocarbons, such
as linear or branched, mono-, and di-substituted C.sub.7-C.sub.16
alkanes, one or more of which is derived from cellulosic-biomass.
It may also contain olefins, substituted or unsubstituted
cycloalkanes (such as cyclopentanes, cyclohexanes), aromatics (such
as benzene, toluene, naphthalenes), mono-substituted aromatics
(such as methyl benzene), di-substituted aromatics (such as
xylenes), and multi-substituted aromatics (such as
trimethylbenzenes), one or more of which is derived from the
cellulosic-biomass.
[0589] In some instances, the unblended cellulosic-biomass derived
gasoline contains less than about 5 percent by weight benzene, such
as less than 4.5, 4.0, 3.5, 3.0, 2.5, 2.0, 1.5, or even less than
1.0 percent by weight, e.g., less than 0.9, 0.8, 0.7, 0.6, 0.5,
0.4, 0.3, or even less than 0.25 percent by weight, e.g., less than
0.2, 0.15, 0.1 or even less than 0.05 percent by weight. In
particular, the methods and catalysts can, for example, if desired,
give the low benzene content directly, without active removal or
separation, such as by distillation of the benzene from other
components. Low concentrations of benzene can be useful in
jurisdictions, such as the United States, that strictly limit its
concentration in gasoline. In the United States, the USEPA sets a
limit of benzene to be less than 1.3 percent by weight in
gasoline.
[0590] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein, such as a high-octane gasoline
(HOG) contains a high aromatics content. For example, the unblended
cellulosic-biomass derived gasoline may contain greater than about
25% (w/w), about 30% (w/w), about 35% (w/w), about 40% (w/w), about
45% (w/w), about 50% (w/w), about 55% (w/w), about 60% (w/w), about
65% (w/w), about 70% (w/w), about 75% (w/w), about 80% (w/w), about
285% (w/w), about 90% (w/w) of aromatic hydrocarbons. In some
instances, the aromatics can include toluene and xylenes, for
example, as o, m- or para-xylene. In some instances, the
predominant aromatics produced are toluene and xylenes, making up
more than about 60 percent by weight of the aromatics produced, for
example, greater than 65, 66, 67, 68, 69, 70, or 72 percent by
weight or even greater, such as greater than about 75 percent by
weight toluene and xylenes. In these instances, these materials can
be distilled to produce pure toluene and xylenes, which can,
respectively, be used to produce compounds such as toluene
diisocyanate and isomers of terephthalic acid.
[0591] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein, such as a HOG can have
relatively low amount of alkanes. For example, the gasoline may
contain less than about 50% (w/w), about 40% (w/w), about 30%
(w/w), about 20% (w/w), about 10% (w/w), about 5% (w/w), about 2%
(w/w), or about 1% (w/w) of alkanes. In some embodiments, the
unblended cellulosic-biomass derived gasoline described herein,
such as a HOG have a ratio of alkanes:aromatics of between about
1:10 and 1:100, such as between 1:10 and 1:50, or between 1:15 and
1:40 or between about 1:15 and 1:25.
[0592] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein, such as a high-octane gasoline
(HOG) contains a low content of dicyclopentadiene. For example, the
gasoline may contain less than 0.4 percent by weight of
dicyclopentadiene, such as less than 0.3, 0.2 or less, such as less
than 0.1 percent by weight.
[0593] Note that, in some instances, adjusting the methods and/or
the catalysts used in the catalytical process described herein may
directly change the chemical properties of the resulting unblended
cellulosic-biomass derived gasoline, and therefore, enabling the
process to obtain an ideal concentration of hydrocarbons without
the need for further dilution, distillation, or blending.
[0594] In some embodiments, the unblended cellulosic-biomass
derived gasoline of such mixtures can be used directly as
transportation fuels, as blending components in transportation
fuels, such as commercial gasoline.
[0595] In one embodiment, the methods and catalysts can, for
example, if needed, produce desired fuels, e.g., motor fuels,
directly without upgrading or downgrading the fuel, such as by
blending. For example, in some instances, the unblended gasoline
produced from reactors can be used in fuel tanks of transportation
vehicles without any additional treatment. The gasolines can be,
for example, a regular octane grade, a mid-octane grade or a
high-octane grade gasoline. In other instances, the gasolines
produced from reactors can be used directly in fuel tanks of
transportation vehicles only after filtering the fuel to remove
particulates, and/or after distillation to remove low boiling
fractions and/or high boiling fractions. In still other
embodiments, the unblended gasolines obtained from the reactors
described herein, can form a blend stock as obtained or after some
purification. For example, in some instances, the unblended
gasolines obtained from the reactors described herein can be a
high-octane blending component, such as having a research octane
number of greater than about 87, about 90, about 91, about 92,
about 93, about 94, about 95, about 96, about 97, about 98, or
about 99.
[0596] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has a boiling point range of
about 35.degree. C. to 200.degree. C. In some embodiments, less
than about 10%, about 9%, about 8%, about 7%, about 6%, about 5%,
about 4%, about 3%, about 2%, or about 1% of the fraction of the
unblended cellulosic-biomass derived gasoline boils at a
temperature above 160.degree. C. In some embodiments, weight
percent of material boiling greater than 220.degree. C. is less
than 0.5 percent, such as less than 0.4, 0.3, 0.25 or less, such as
less than 0.1 percent by weight.
[0597] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has an oxygenate level of less
than about 0.5% (wt./wt.), about 0.4% (wt./wt.), about 0.25%
(wt./wt.), or about 0.1% (wt./wt.). As used herein, the term
"oxygenates" is defined to include oxygen containing organic
compounds such as alcohols, ethers, carbonyl compounds (aldehydes,
ketones, carboxylic acids, carbonates, and the like).
Representative oxygenates include, but are not necessarily limited
to, lower straight chain or branched aliphatic alcohols, their
unsaturated counterparts. Examples include but are not necessarily
limited to: methanol; ethanol; n-propanol; isopropanol; C4-C10
alcohols; methyl ethyl ether; dimethyl ether; diethyl ether;
di-isopropyl ether; methyl mercaptan; methyl formate, methyl
acetate, formaldehyde; di-methyl carbonate; trimethyl orthoformate,
and dimethyl ketone. Oxygenates such as acetaldehyde and acetone
can be corrosive and can damage gaskets in engine components. They
can also make the fuel hygroscopic, allowing it to absorb water,
thereby impacting the quality of gasoline. So, in some embodiments
having low oxygenate content in gasoline may be desirable.
[0598] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has a naphthalene content of less
than about 0.5% (wt./wt.), about 0.4% (wt./wt.), about 0.25%
(wt./wt.), or about 0.1% (wt./wt.). Naphthalenes are toxic air
pollutants, add unfavorable smell to gasoline and are recognized as
possible human carcinogens. So, in some embodiments having low
naphthalene content in gasoline may be desirable.
[0599] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has an aromatic content of
greater than about 75% (wt./wt.), about 76% (wt./wt.), about 77%
(wt./wt.), about 78% (wt./wt.), about 79% (wt./wt.), about 80%
(wt./wt.), about 85% (wt./wt.).
[0600] In some embodiments, the unblended cellulosic-biomass
derived gasoline contains carbon between about 82 to 94 percent by
weight, such as between 85 and 94, or 89 and 93 percent by
weight.
[0601] In some embodiments, the unblended cellulosic-biomass
derived gasoline contains hydrogen between about 6 and 18 percent
by weight, such as between 6 and 10 or 7 and 9 percent by
weight.
[0602] In some embodiments, the unblended cellulosic-biomass
derived gasoline contains oxygen and nitrogen where each are less
than 1 percent by weight, such as 0.9, 0.8, 0.7, 0.6, 0.5 or less,
such as less than 0.25 or less, such as less than 0.1 or less, such
as even less than 0.01 percent by weight.
[0603] In some embodiments, the unblended cellulosic-biomass
derived gasoline has sulfur content meets or exceeds tier 3
requirements of less than 10 ppmw, such as less than less than 9,
8, 7, 6, 5, 4, or even less than 3, such as less than 1 ppmw.
[0604] In some embodiments, the unblended cellulosic-biomass
derived gasoline has a total acid content, defined as a sum of all
carboxylic and phenolic compounds present, of less than 0.25
percent by weight, such as less than 0.2, 0.15, 0.1 or less, such
as less than 0.01 percent by weight.
[0605] In some embodiments, the unblended cellulosic-biomass
derived gasoline described herein has the vapor pressure less than
14 psi. For example, the vapor pressure can be less than about 13
psi, about 12 psi, about 11 psi, about 10 psi, about 9 psi, about 8
psi, about 7 psi, about 6 psi or less, such as less than 5 psi.
Examples
[0606] Several biomass-derived fuel samples generated by the
processes disclosed herein are further described in more detail
below.
[0607] FIG. 40 describes the compositions (volume %) of samples D1
to D6. Sample D1 is 100% Trufuel.RTM.; sample D2 is a mixture of
90% (v/v) high-octane gasoline (HOG) (Fraction 2b) generated by the
catalytic processing of biomass-derived ethanol described herein,
and 10% (v/v) of ethanol; sample D3 is 100% (v/v) high-octane
gasoline (HOG) (Fractions 1b and 2b) generated by the catalytic
processing of biomass-derived ethanol described herein; sample D4
is 100% (v/v) high-octane gasoline (HOG) (Fraction 2b) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample D5 is 100% (v/v) of high-octane gasoline (HOG) (all
fractions) generated by the catalytic processing of biomass-derived
ethanol described in Example 6; sample D6 is a mixture of 50% (v/v)
low-octane gasoline (LOG) (Fractions 1a and 2a) generated by the
catalytic processing of biomass-derived ethanol described in
Example 7, and 50% (v/v) of ethanol. Fraction 1 is a portion of the
HOG or LOG that has a boiling range below 30.degree. C. ("low
boiling range fractions"), Fraction 2 is a portion of the HOG or
LOG that has a boiling range between 35 to 200.degree. C. ("mid
boiling range fractions"), and Fraction 3 is a portion of the HOG
or LOG that has a boiling range above 200.degree. C. ("high boiling
range fraction"). Letters "a" and "b" distinguishes the fractions
from the HOG from the fractions from the LOG. For example, Fraction
1a represents low boiling range fractions from the LOG, while
Fraction 1b represents low boiling range fractions from the
HOG.
[0608] For samples composed of a mix of fractions, FIG. 41 shows
the volume percentages and the weight percentages of the fractions
within. FIG. 41 shows that sample D3 is a HOG with about 13.06%
(v/v) of Fraction 1b, and about 86.93% (v/v) of Fraction 2b. It
also has about 11.89 wt. % of Fraction 1, and about 88.10 wt. % of
Fraction 2. Sample D5 is a HOG with about 14.30% (v/v) of Fraction
1, about 93.29% (v/v) of Fraction 2, and about 2.40% (v/v) of
Fraction 3. It also has about 11.97 wt. % of Fraction 1, about
85.22 wt. % of Fraction 2, and about 2.70 wt. % of Fraction 3.
Lastly, Sample D6 is a LOG with about 12.56% (v/v) of Fraction 1,
about 74.89% (v/v) of Fraction 2, and about 4.68% (v/v) of Fraction
3. In addition, it has about 18.61 wt. % of Fraction 1, about 75.71
wt. % of Fraction 2, and about 5.67 wt. % of Fraction 3.
[0609] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D1, which contains Trufuel.RTM., a commercially
available premixed high-octane ethanol-free fuel, is shown in FIG.
42. Based on the total known components, it contained about 33.47%
of aromatic hydrocarbons, about 0.01% of alkenes, about 63.07% of
alkanes, and about 0.13% of oxygenated compounds (wt./wt.). FIG. 42
also provides a detailed breakdown of all the detectable compounds
in sample D1.
[0610] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D2, which is a mixture of about 90% (v/v) of
Fraction 2b distilled from the high-octane gasoline (HOG) generated
by the catalytic processing of biomass-derived ethanol described
herein, and about 10% (v/v) of biomass-derived ethanol, is shown in
FIG. 43. Based on the total known components, it contained about
53.79% of aromatic hydrocarbons, about 17.61% of alkenes, about
18.64% of alkanes, and about 3.64% of oxygenated compounds
(wt./wt.). FIG. 43 also provides a detailed breakdown of all the
detectable compounds in sample D2.
[0611] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D3, which contains 100% (v/v) of Fraction 1b and
Fraction 2b of the high-octane gasoline (HOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
is shown in FIG. 44. Based on the total known components, it
contained about 62.51% of aromatic hydrocarbons, about 11.96% of
alkenes, about 16.97% of alkanes, and about 1.72% of oxygenated
compounds (wt./wt.). FIG. 44 also provides a detailed breakdown of
all the detectable compounds in sample D3.
[0612] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D4, which contains 100% (v/v) of Fraction
Fraction 2b of the high-octane gasoline (HOG) generated by the
catalytic processing of biomass-derived ethanol described herein,
is shown in FIG. 45. Based on the total known components, it
contained about 60.04% of aromatic hydrocarbons, about 15.48% of
alkenes, about 16.39% of alkanes, and about 0.85% of oxygenated
compounds (wt./wt.). FIG. 45 also provides a detailed breakdown of
all the detectable compounds in sample D4.
[0613] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D5, which contains 100% (v/v) of the high-octane
gasoline (HOG) generated by the catalytic processing of
biomass-derived ethanol described herein without further
distillation, is shown in FIG. 46. Based on the total known
components, sample D5 contained about 62.98% of aromatic
hydrocarbons, about 12.41% of alkenes, about 16.02% of alkanes, and
about 1.74% of oxygenated compounds (wt./wt.). FIG. 46 also
provides a detailed breakdown of all the detectable compounds in
sample D5.
[0614] A graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in sample D6, which is a mixture of about 50% (v/v) of
fractions 1a and 2a distilled from the low-octane gasoline (LOG)
generated by the catalytic processing of biomass-derived ethanol
described herein, and about 50% (v/v) of biomass-derived ethanol,
is shown in FIG. 47. Based on the total known components, it
contained about 5.77% of aromatic hydrocarbons, about 2.61% of
alkenes, about 55.00% of alkanes, and about 30.99% of oxygenated
compounds (wt./wt.). FIG. 47 also provides a detailed breakdown of
all the detectable compounds in sample D6.
[0615] FIG. 48 provides the results of analyzing samples of blends
of high-octane gasoline of samples D1-D6, described above. The API
Gravity @ 60.degree. F. is measured according to ASTM D4052, the
Dry Vapor Pressure Equivalent (DVPE) EPA is measured according to
ASTM D5191-13, the gross heat of combustion is measured according
to ASTM D4809, the research octane number (RON) is measured
according to ASTM D2699, the motor octane number (MON) is measured
according to ASTM D2700, the sulfur content is measured according
to ASTM D7039, the benzene content is measured according to ASTM
D3606, the odor is measured according to ASTM D1296, the water
content is measured according to ASTM E1064, the corrosion to
copper strips is measured according to ASTM D130, and the corrosion
to silver strips is measured according to ASTM D4814-A1, and the
antiknock index or octane rating ((RON+MON)/2) is measured
according to D4814-X1.4. The data shows that blending the gasolines
produced by the processes described herein does not significantly
alter the RON, MON, gross heat of combustion and antiknock index of
the blend. This demonstrates that the unblended cellulosic-biomass
derived gasolines, in particular the HOGs have a high octane rating
similar to that of Trufuel.RTM.. In fact, sample D5, which contains
only 100% of HOG produced by the processes described herein has a
high RON of 97.4, MON of 85.3, antiknock index of 91.4, and gross
heat of combustion of 128,194 BTU/gal. Notably, it also contains
other desirable attributes similar to that of Trufuel.RTM.. For
instance, the sulfur level is below 3.2 mg/kg, the odor level is
noncharacteristic, the corrosion to copper strips is at 1a, and the
corrosion to silver strips is at 0.
Methods for Producing the Unblended Gasoline
[0616] Provided herein is an exemplary method for preparing
unblended gasoline comprising: treating a lignocellulosic biomass
with a beam of electrons and saccharifying the irradiated biomass
to produce sugars; fermenting the sugars with a microorganism to
produce one or more alcohols; and catalytically converting the one
or more alcohols in a reactor into a hydrocarbon mixture having a
fraction boiling at a range of about 35.degree. C. to about
200.degree. C., thereby producing an unblended gasoline, wherein
the unblended gasoline has an octane number of greater than 60 as
determined by ASTM D2699.
[0617] An unblended gasoline is a liquid gasoline produced by the
processes described herein without further mixing or blending with
other components. For example, an unblended gasoline refers to the
liquid reaction product obtained from the one or more reactors, in
which alcohol is catalytically converted to hydrocarbons by the
processes. In some embodiments, the unblended gasoline is the
product emerging from a single reactor without further processing.
In some embodiments, the unblended gasoline could be produced by
distillation of the reaction product from the one or more reactors
into a fraction with a specified boiling point range, such as HOG
and LOG, while in other embodiments, no distillation of the
reaction products may be involved. The unblended gasoline could be
further mixed with other components such as ethanol or additional
hydrocarbons to produce blended compositions with superior
properties. In some embodiments these additional components for
blending, such as ethanol and hydrocarbons, are produced from
cellulosic biomass by the processes described herein.
[0618] In some embodiments, corn cobs are used as the
lignocellulosic biomass, but other suitable feedstocks disclosed
herein can also be used.
[0619] In some embodiments, the method further comprises treating
corn cobs a beam of electrons. In some embodiments, the irradiating
(with any radiation source or a combination of sources) is
performed until the cellulosic-biomass receives a dose of at least
0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, at least 5.0
Mrad, or at least 10.0 Mrad. In some embodiments, the irradiating
is performed until the material receives a dose of between 1.0 Mrad
and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad. In some
embodiments, the irradiating is performed at a dose rate of between
5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0
kilorads/hour or between 50.0 and 350.0 kilorads/hours.
[0620] In some embodiments, the method further comprises
saccharifying the treated corn cobs with an enzyme in an aqueous
solution to produce sugars. In some embodiments, the enzyme used is
produced by Trichoderma reesei strain. In some embodiments, the
enzymes used is one or more of endoglucanases, cellobiohydrolases,
or cellobiase.
[0621] In some embodiments, the method further comprises fermenting
the sugars with a microorganism to produce one or more alcohols. In
some embodiments, the microorganism is at of least one of a
bacterium, a yeast, a fungus, a plant, a protozoa, or a fungus-like
protist. In some embodiments, the method further uses Saccharomyces
cerevisiae, C. acetobutylicum, or a type of C5 fuel yeast, to
ferment the sugars.
[0622] In some embodiments, the method further requires the
fermenting process to include adding acids or bases to control the
pH level, and maintaining fermentation temperature between about 20
and 50.degree. C. In some embodiments, the alcohols produced by the
process is one or more of methanol, ethanol, n-propanol,
iso-propanol, n-butanol, iso-butanol, sec-butanol, as well as
longer chained alcohols, R C5-C20, aldehydes, ketone, acetone, or
any combination thereof.
[0623] In some embodiments, subsequent to the fermenting process,
the method catalytically converts the one or more alcohols in a
reactor into a hydrocarbon mixture having a fraction boiling at a
range of about 35.degree. C. to about 200.degree. C. In some
embodiments, the conversion process uses one or more catalysts
selected from alumina, transition metal oxides,
silicoaluminophosphates, zeolite catalysts, and acidic
catalysts.
[0624] In some embodiments, the reactor used in the process is a
single stage reactor. A single stage reactor uses only one reactor
for the reactions described herein, such as the catalytic
conversion of alcohol to hydrocarbons. For example, in a reactor
converting alcohol to hydrocarbon, the feedstock containing alcohol
is fed into the reactor and the reaction products are collected
without sending them into another reactor for further reaction.
Thus, the catalytic conversion of alcohol to hydrocarbon is
achieved in one reactor only as opposed to multiple reactors
involving multiple types of reactions. In operation, although more
than one reaction may occur in the single stage reactor, the
temperature and pressure generally do not vary across the single
stage reactor. In some embodiments, the pressure, temperature and
other reaction conditions can be varied across the reactor
temporally and spatially. In some embodiments, the temperature,
pressure, and other operating conditions are kept constant. In some
embodiments, the temperature varies across the reactor as a
function of the catalyst occupying the reactor, but the pressure
and other operating conditions are held constant. In some
embodiments, the pressure varies across the reactor as a function
of the catalyst occupying the reactor, but the temperature and
other operating conditions are held constant. Furthermore, in some
embodiments, the single stage reactor may contain only one catalyst
bed. In some embodiments, the single stage reactor may contain more
than one catalyst bed. In some embodiments, the single stage
reactor may be further connected to a fractionation or distillation
tower in which the products of the single stage reactor are
distilled into different factions.
[0625] In one embodiment, the reactor used has a liquid hourly
space velocity (LHSV) of about 3.5 per hour. LHSV equals to the
volumetric flow rate of reactants entering the reactor divided by
the volume of the reactor. LHSV defines the amount of reactant that
a known volume reactor can process per hour. For example, if a
reactor has LHSV about 3.5 per hour and the volume of the reactor
is about 3 mL, the reactor will theoretically be able to process
about 10.5 mL of reactant per hour. In some embodiments, the LHSV
of the reactor is between about 0.1 per hour to 50 per hour,
between about 1.5 per hour and 10 per hour, between about 2.0 and
6.0, or between about 2.5 and 5 per hour. In some embodiments, the
LHSV of the reactor is about 0.1 per hour, about 1 per hour, about
1.5 per hour, about 2 per hour, about 2.5 per hour, about 3 per
hour, about 3.5 per hour, about 4 per hour, about 4.5 per hour,
about 5 per hour, about 5.5 per hour, about 6 per hour, about 6.5
per hour, about 7 per hour, about 7.5 per hour, about 8 per hour,
about 8.5 per hour, about 9 per hour, about 9.5 per hour, or about
10 per hour.
[0626] In one embodiment, the catalyst used is zeolite HZSM-5. And
the method further comprises: pre-activating Zeolite HZSM-5 at
about 450.degree. C., under about 500 psi of an inert gas, and for
about two hours; setting the reactor's internal temperature to
about 350.degree. C.; pre-heating the alcohol from the fermenting
step to about 100.degree. C.; and pumping the heated alcohol from
the fermenting step into the reactor. In some embodiments, the
inert gas is nitrogen. One of the unique features of the claimed
method is that the conversion of alcohol to hydrocarbon takes place
without needing to supply a reducing gas such as hydrogen.
[0627] In one embodiment, the catalyst used is 0.5% Pt/0.5%
H.sub.3BO.sub.3--Al.sub.2O.sub.3. And the method further comprises:
reducing 0.5% Pt/0.5% H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst
in-situ at about 450.degree. C., under about 725 psi of hydrogen
gas, and for about 10 hours; purging the reactor with an inert gas;
setting the reactor's internal temperature to about 350.degree. C.
in inert gas flow; pre-heating the alcohol from the fermenting step
to about 100.degree. C.; and pumping the heated alcohol from the
fermenting step into the reactor. In some embodiments, the inert
gas is nitrogen. One of the unique features of the claimed method
is that the conversion of alcohol to hydrocarbon takes place
without needing to supply a reducing gas such as hydrogen.
Example 6: Process for Producing Unblended HOGs
[0628] One of methods for producing an unblended high-octane
gasoline (HOG) from cellulosic biomass is described here. Batches
of corn cobs were initially treated with a beam of electrons to a
dose of between about 5 to 50 Mrad to reduce the recalcitrance of
the lignocellulosic material. Subsequently, the
electron-beam-treated corn cobs were saccharified with an enzyme
produced from a Trichoderma reesei strain to make sugars. The
sugars, then, were fermented using Saccharomyces cerevisiae.
Saccharomyces cerevisiae is a microorganism capable of fermenting
both glucose and xylose to produce ethanol.
[0629] To convert the ethanol into a gasoline, a single stage
reactor was used. Before feeding the ethanol into the reactor,
about 2.3 grams of zeolite HZSM-5 catalyst was pre-activated inside
the reactor. The zeolite HZSM-5 was pre-activated at about
450.degree. C., under about 500 psi of pressure, and exposed to
nitrogen gas flow at about 50 mL/min for about two hours. Once the
zeolite HZSM-5 was activated, the reactor's internal temperature
was adjusted to about 350.degree. C., the pressure was set to 500
psi, and the flow rate of nitrogen gas was set to 50 mL/min. This
operating condition was maintained throughout the conversion
process. The ethanol obtained from the fermenting step was then
heated to about 100.degree. C. before feeding into the reactor. The
single stage reactor had a volume of about 3.1 mL. The LHSV for the
reaction was about 3.5 per hour. Hence, the reactor catalytically
converted approximately 10.85 mL of ethanol into the HOG every
hour.
[0630] The process described above produced the HOG with the
attributes and characteristics shown in FIG. 46 without further
distillation or dilution.
Example 7: Process for Producing Unblended LOGs
[0631] One of the methods for producing an unblended low-octane
cellulosic gasoline (LOG) is described here. Batches of corn cobs
were initially treated with a beam of electrons to a dose of
between about 5 to 50 Mrad to reduce the recalcitrance of the
lignocellulosic material. Subsequently, the electron-beam-treated
corn cobs were saccharified with an enzyme produced from a
Trichoderma reesei strain to make sugars. The sugars, then, were
fermented using Saccharomyces cerevisiae.
[0632] To convert the ethanol into a gasoline, a single stage
reactor was used. Before feeding the ethanol into the single stage
reactor, a 0.5% Pt/0.5% H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst
was prepared. The preparation involved pre-treating Al.sub.2O.sub.3
support with 5% H.sub.3BO.sub.3. The 2.6368 grams of
H.sub.3BO.sub.3 was dissolved in 34 mL of water and then added
drop-wise to the 25 grams of Al.sub.2O.sub.3 support with proper
mixing. After the addition was completed, the H.sub.3BO.sub.3
treated Al.sub.2O.sub.3 support was kept at room temperature for 3
hours. Then, the H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst was dried
at 110.degree. C. for 10 hours in a vacuum oven and calcined under
air at 500.degree. C. for 3 hours. Following the preparation steps,
the catalyst was reduced in-situ at about 450.degree. C., under
about 725 psi of pressure, and exposed to a hydrogen gas flow at
about 100 mL/min for about 10 hours. The reactor was subsequently
purged with nitrogen gas. With the 0.5% Pt/0.5%
H.sub.3BO.sub.3-Al.sub.2O.sub.3 catalyst prepared, the reactor's
internal temperature was then adjusted to about 350.degree. C., the
pressure was set to 500 Psi, and the flow rate of nitrogen gas was
set to about 50 mL/min. This operating condition was maintained
throughout the conversion process. The ethanol obtained from the
fermenting step was heated to about 100.degree. C. before feeding
into the reactor. The single stage reactor used here has a volume
of about 3.1 mL. The LHSV for the reaction was about 3.5 per hour.
Hence, the reactor catalytically converted approximately 10.85 mL
of ethanol into a LOG every hour.
Unblended Gasoline with High Percentage of Biogenic Carbon
Content
[0633] Provided herein is an unblended gasoline of high research
octane number derived from cellulosic biomass, and a method for
producing the same. The unblended gasoline is a liquid produced by
the process described herein without further mixing or blending.
And, in some embodiments, the unblended gasoline comprises a liquid
produced by the processes described herein that has been further
distilled in the gasoline distillation range from 900 F to 4100 F.
In one embodiment, the unblended gasoline is produced by catalytic
processing of the cellulosic-biomass or a product derived
therefrom. In one embodiment, the research octane number of the
unblended gasoline is greater than about 87, as determined by ASTM
D2699. For example, the unblended gasoline can have a research
octane number (RON) of greater than about 60, about 65, about 70,
about 75, about 80, about 85, about 87, about 90, about 91, about
92, about 93, about 94, about 95, about 96, about 97, about 98, or
about 99. The catalyst used in this process can be any of the
catalysts disclosed herein, including an alumina-based catalyst
and/or a zeolite-based catalyst. In some embodiments, the catalyst
is a mono-metallic catalyst, bi-metallic catalyst, or tri-metallic
catalyst. In some embodiments, the catalysts contain metals
selected from the group consisting of Pt, Pd, Sn, Re, Rh, Bi, Ba,
Ti, Ni, and any combinations thereof.
[0634] In some embodiments, the unblended gasoline has a relatively
high percentage of biogenic carbon content as determined by ASTM
D6866-18 (approved Mar. 1, 2018), which is incorporated here by
reference. For example, the percentage of biogenic carbon content
("% biogenic carbon") can be greater than about 50, about 55, about
60, about 65, about 70, about 75, about 80, about 85, about 90,
about 91, about 92, about 93, about 94, about 95, about 96, about
97, about 98, or about 99. In some embodiments, the unblended
gasoline has about 100 percent of biogenic carbon content. A value
of 100% biogenic carbon would indicate that 100 percent of the
carbon came from plants or animal by-products (biomass) existing in
the natural environment, other than fossil fuels, and a value of 0%
would mean that all of the carbon was derived from petrochemicals,
coal and other fossil sources. A value between 0-100% would
indicate a mixture. The higher the value, the greater the
proportion of biomass-sourced components is in the material.
[0635] According to ASTM D6866-18, % biogenic carbon content is the
amount of biogenic carbon in the material or product as a percent
of the total carbon (Total Carbon) in the product. In some
instances, the percentage of the biologically-derived carbon can
also be reported as "% biobased carbon," which refers to the amount
of biogenic carbon in the material or product as a percent of the
total organic carbon. In contrast to biobased carbon, biogenic
carbon refers to the amount of biomass-derived carbon as a
percentage of total carbon (organic and inorganic). In practice,
both "% biogenic carbon" and "% biobased carbon" are standard units
in regulatory and industrial applications. In addition, both units
are obtained by using the same analytical procedure for measuring
radiocarbon contents.
EXAMPLES
[0636] Several biomass-derived fuel samples generated by the
processes disclosed herein are further analyzed under ASTM
D6866-18, as described below.
[0637] FIG. 49 describes the compositions (volume %) of samples E1
to E8. Sample E1 is 100% high-octane gasoline (HOG) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample E2 is 100% low-octane gasoline (LOG) generated by
the catalytic processing of biomass-derived ethanol described
herein; sample E3 is 100% cellulosic ethanol generated by the
process described herein; sample E4 is a mixture of 95% HOG with 5%
of cellulosic ethanol, derived by the process described herein;
sample E5 is a mixture of 95% LOG with 5% of cellulosic ethanol,
derived by the process described herein; sample E6 is a
commercially available gasoline--Trufuel.RTM.; sample E7 is a
mixture of 50% HOG with 50% Trufuel.RTM.; sample E8 is a mixture of
50% cellulosic ethanol, derived by the process described herein,
with 50% Trufuel.RTM.. The HOG and LOG in samples E1, E2, E4, E5
and E6 are distilled to contain fractions from three different
boiling ranges. Fraction 1 is a portion of the HOG or LOG that has
a boiling range below 30.degree. C. ("low boiling range
fractions"), fraction 2 is a portion of the HOG or LOG that has a
boiling range between 35 to 200.degree. C. ("mid boiling range
fractions"), and fraction 3 is a portion of the HOG or LOG that has
a boiling range above 200.degree. C. ("high boiling range
fraction"), excluding a small portion that has a boiling point
significantly higher than 200.degree. C.
[0638] FIG. 50 describes the % biogenic carbon content in samples
E1 to E8 as determined by ASTM D6866-18. The test results in FIG.
50 were obtained from a test procedure described in ASTM D6866-18
Method B (AMS). The analytical measurement is cited as percent
modern carbon (pMC). This is the percentage of C14 measured in the
sample relative to modern reference standard, NIST SRM 4990C, which
is incorporated here by reference. Zero pMC represents the entire
lack of measurable C14 atoms in a material above background signals
thus indicating a fossil (for example, petroleum based) carbon
source. One hundred pMC indicates an entirely modern carbon source.
A pMC value between 0 and 100 indicates a proportion of carbon
derived from fossil vs. modern source. The pMC can be greater than
100% due to the continuing but diminishing effects from injection
of C14 into the atmosphere with atmospheric nuclear testing
programs discussed in ASTM D6866-18. Because all sample C14
activities are referenced to the pre-bomb NIST traceable standard,
all pMC values must be adjusted by atmospheric correction factor
("REF") to obtain the true biobased content of the sample. The
correction factor is based on the excess C14 activity in the
atmosphere at the time of testing. Hence, in FIG. 50, all %
biogenic carbon contents were adjusted by a REF value for C14 in
carbon dioxide at the time of the testing.
[0639] In FIG. 50, samples E1-E5 all have about 100% biogenic
carbon content (as a fraction of total carbon). Specifically,
sample E1 has about 103.17 pMC; sample E2 has about 101.98 pMC;
sample E3 has about 102.72 pMC; sample E4 has about 102.45 pMC;
and, sample E5 has about 102.40 pMC. Sample E6, 100% Trufuel.RTM.,
has about 0% biogenic carbon content (as a fraction of total
carbon), and about 100% of fossil carbon. Specifically, sample E6
has less than about 0.44 pMC. Sample E7 has about 62% biogenic
carbon content (as a fraction of total carbon), and about 38% of
fossil carbon. Specifically, sample E7 has about 62.59 pMC. Lastly,
sample E8 has about 44% biogenic carbon content (as a fraction of
total carbon), and about 56% of fossil carbon. Specifically, sample
E8 has about 44.40 pMC.
E80/HOG Gasoline
[0640] In an embodiment, a fuel containing about 80% cellulosic
ethanol (E80) and 20% of cellulose-derived high-octane gasoline
(HOG) by volume was produced and tested. The cellulosic ethanol was
prepared according to the following method. About 45,000 lbs of
ground corn cobs were treated with a dose of 40 Mrad electron beam
radiation. The ground corn cobs had a maximum dimension of about 1
mm in size. The treated corn cobs were then added to a 50,000
gallon stainless steel vessel containing 30,000 gallons of water.
Subsequently, about 30 metric tons of cellulase enzyme cocktail
produced by genetically modified T. reesei (such as one originating
from the RUT-C30 strain) (1.0% active) solution (approximately
8,250 gallons) was added for saccharification. A jet mixer was used
during the saccharification phase to continuously agitate the
mixture. During the saccharification reaction, the pH was adjusted
and maintained at 5.0 by adding sodium hydroxide and 85 percent
phosphoric acid. The saccharification reaction continued for 72
hours at about 50.degree. C. At the 72-hour mark, the total sugar
concentration was about 74 g/L. The mixture was then cooled to
33.degree. C. and inoculated with Angel Cellulosic Ethanol Active
Dry Yeast capable of generating ethanol from both the xylose and
glucose. The yeast fermented the sugar for about 30 hours. The end
product had an ethanol concentration of about 31 g/L (approximately
3.1 percent in volume). The solids in the end product were removed
by a filter belt and two-stage ultrafiltration (UF) systems. The
two-stage UF system contains a first membrane, which is a tubular
membrane having a molecular weight cutoff of 200,000 and a second
membrane, which is a spiral membrane having a molecular weight
cutoff of 10,000. The filter belt was obtained from Westech
Engineering, Salt Lake City, Utah and run at 75 gpm. After the
filtration, the end product was distilled and dehydrated to produce
anhydrous ethanol, approximately 1500 gallons.
[0641] The HOG used in this fuel composition is the same gasoline
described as sample D5 above. Its attributes are shown in FIGS. 46
and 48. The E80/HOG has a biogenic carbon content of about 100%.
The cellulosic ethanol and the cellulose-derived HOG also have
their respective biogenic carbon content at about 100% as
determined by ASTM D6866-18. See FIGS. 49 and 50 (sample E1
represents the HOG, and sample E3 represents the cellulosic
ethanol). The cellulose-derived HOG used in the E80/HOG mixture has
a boiling range between 35 to 200.degree. C. And among other
attributes, the cellulose-derived HOG also has a research octane
number of about 97 as determined by ASTM D2699, a motor octane
number of about 85, as determined by ASTM D2700, an antiknock index
of about 91, as determined by ASTM D4814-X1.4, API Gravity at
60.degree. F. of about 53.degree. API, as determined by ASTM D4052,
a dry vapor pressure of about 10 psi, as determined by ASTM D5191,
and a gross heat of combustion of about 128,0000 Btu/gal.
[0642] The E80/HOG fuel was tested in a commercial vehicle and no
operational or performance differences were observerd in comparison
to commercially available gasoline. In the test, about 5.25 oz of
STP.RTM. gas treatment was added to about 20 gallons of the E80/HOG
unblended gasoline. By volume, the STP.RTM. gas treatment
constituted about 0.002% of the fuel mixture. The fuel mixture was
then added to the gas tank of a Ford 350 flex fuel truck. A week of
testing on both the highway and local roads showed no observable
difference in the truck's operation and performance. STP.RTM. gas
treatment was added to keep fuel injectors and intake valves clean.
It provides the benefit of keeping fuel intake system clean,
prevent fuel line freeze, and prevent deposit build up. While
STP.RTM. gas treatment was used as the cleaning agent of choice
here, other types of cleaning agents can also be used.
Methods of Producing Cellulosic Biomass-Derived Jet Fuel
[0643] Also provided herein is a method of producing jet fuel from
cellulosic biomass produced from by the methods described herein.
For example, cellulosic ethanol can be converted to jet fuel by
catalytic conversion over one or more of the catalysts described
herein. Jet fuel produced thereby can be based on either an
unleaded kerosene (Jet A-1), or a naphtha-kerosene blend (Jet B).
The jet fuels produced hereby can be used to operate compression
ignition engines and jet turbines, with or without blending with
additional components.
[0644] In one embodiment, the cellulosic-biomass derived jet fuel
is produced by catalytically processing a cellulosic-biomass
derived ethanol. The cellulosic-biomass may be further pretreated
with electron beam radiation. In some embodiments, the irradiating
(with any radiation source or a combination of sources) is
performed until the cellulosic-biomass receives a dose of at least
0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, at least 5.0
Mrad, or at least 10.0 Mrad. In some embodiments, the irradiating
is performed until the material receives a dose of between 1.0 Mrad
and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad. In some
embodiments, the irradiating is performed at a dose rate of between
5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0
kilorads/hour or between 50.0 and 350.0 kilorads/hours.
[0645] The cellulosic-biomass derived jet fuel produced by this
invention can be a mixture of different hydrocarbons, such as
linear or branched, mono-, and di-substituted C7-C16 alkanes, one
or more of which is derived from cellulosic-biomass. It may also
contain olefins, substituted or unsubstituted cycloalkanes (such as
cyclopentanes, cyclohexanes), aromatics (such as benzene, toluene,
naphthalenes), mono-substituted aromatics (such as methyl benzene),
di-substituted aromatics (such as xylenes), and multi-substituted
aromatics (such as trimethylbenzenes), one or more of which is
derived from the cellulosic-biomass.
[0646] In some instances, the cellulosic-biomass derived jet fuel
contains less than about 5 percent by weight alkene, such as less
than about 4.5, 4.0, 3.5, 3.0, 2.5, 2.0, 1.5, or even less than 1.0
percent by weight, e.g., less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4,
0.3, or even less than 0.25 percent by weight, e.g., less than 0.2,
0.15, 0.1 or even less than 0.05 percent by weight. In some
embodiments, the jet fuel has about 2.5% (w/w) of alkenes. In
particular, the methods and catalysts can, for example, give the
low alkene content directly, without active removal or separation,
such as by distillation of the alkene from other components.
[0647] In some embodiments, the cellulosic-biomass derived jet fuel
described herein has an aromatics content of about 15-20% (w/w),
about 20-25% (w/w), about 25-30% (w/w), about 30-35% (w/w), about
35-40% (w/w), about 40-45% (w/w), about 45-50% (w/w) of aromatic
hydrocarbons. In some embodiment, the jet fuel has about 25% (w/w)
of aromatic hydrocarbons.
[0648] In some embodiments, the cellulosic-biomass derived jet fuel
described herein has 25-30% (w/w), about 30-35% (w/w), about 35-40%
(w/w), about 40-45% (w/w), about 45-50% (w/w), about 50-55% (w/w),
55-60% (w/w), 60-65% (w/w), 65-70% (w/w) of alkanes. In some
embodiment, the jet fuel has about 41% (w/w) of alkanes.
[0649] Note that, in some instances, adjusting the methods and/or
the catalysts used in the catalytical process described herein may
directly change the chemical properties of the resulting unblended
cellulosic-biomass derived jet fuel, and therefore, enabling the
process to obtain an ideal concentration of hydrocarbons without
the need for further dilution, distillation, or blending.
[0650] In some embodiments, the cellulosic-biomass derived jet fuel
of such mixtures can be used directly as transportation fuels, as
blending components in transportation fuels, such as commercial jet
fuel.
[0651] In some embodiments, the cellulosic-biomass derived jet fuel
described herein has an oxygenate level of less than about 10%
(wt./wt.), about 5% (wt/wt.), about 3% (wt/wt.), about 0.5%
(wt./wt.), about 0.4% (wt./wt.), about 0.25% (wt./wt.), or about
0.1% (wt./wt.). In some embodiment, the jet fuel has about 8-9%
(wt./wt.) of oxygenates. As used herein, the term "oxygenates" is
defined to include oxygen containing organic compounds such as
alcohols, ethers, carbonyl compounds (aldehydes, ketones,
carboxylic acids, carbonates, and the like). Representative
oxygenates include, but are not necessarily limited to, lower
straight chain or branched aliphatic alcohols, their unsaturated
counterparts. Examples include but are not necessarily limited to:
methanol; ethanol; n-propanol; isopropanol; C4-C10 alcohols; methyl
ethyl ether; dimethyl ether; diethyl ether; di-isopropyl ether;
methyl mercaptan; methyl formate, methyl acetate, formaldehyde;
di-methyl carbonate; trimethyl orthoformate, and dimethyl ketone.
Oxygenates such as acetaldehyde and acetone can be corrosive and
can damage gaskets in engine components. They can also make the
fuel hygroscopic, allowing it to absorb water, thereby impacting
the quality of gasoline. So, in some embodiments having low
oxygenate content in gasoline may be desirable.
EXAMPLES
[0652] Preparation of 0.5% Pt-0.25% Re/.gamma.-Al.sub.2O.sub.3
[0653] 0.5% Pt-0.25% Re/.gamma.-Al.sub.2O.sub.3 catalyst was
prepared by sequential incipient wetness impregnation method. The
metal precursor salts Hexachloroplatinic acid (H.sub.2PtCl.sub.6),
and ammonium perrhenate (NH.sub.4ReO.sub.4) were used for the
preparation of bimetallic Pt--Re catalysts. First, 0.25%
Re/.gamma.-Al.sub.2O.sub.3 catalyst was prepared by dissolving the
corresponding amount of NH.sub.4ReO.sub.4 in appropriate amount of
DI water and adding to stoichiometric amounts of
.gamma.-Al.sub.2O.sub.3 dropwise with proper mixing. It was
subsequently dried at 110.degree. C. for 10h under vacuum oven, and
calcined under air at 500.degree. C./3h. Second, 0.25%
Re/.gamma.-Al.sub.2O.sub.3 was impregnated with 0.5% Pt using
stoichiometric amount of H.sub.2PtCl.sub.6 dissolve in required
amount of DI water and by dropwise addition of metal salt solution
to the 0.25% Re/.gamma.-Al.sub.2O.sub.3 catalyst. This was then
dried at 110.degree. C. for 10h under vacuum oven and calcined
under air at 500.degree. C./3h.
Reaction Conditions:
[0654] Cellulosic ethanol produced by the methods described herein
is converted to jet fuel by catalytic conversion over the 2.3 g of
0.5% Pt-0.25% Re/.gamma.-Al.sub.2O.sub.3 prepared above. The
process was carried out in a 3.7 cm.sup.3 reactor. Before the
reaction, the catalyst was reduced at 450.degree. C., 700 Psi
H.sub.2-100 cc/min for 10h. The reaction was run at a temperature
of 400.degree. C., pressure of 700-900 Psi N.sub.2--50 cc/min and
ethanol flow rate of 0.4 mL/min. All condensable hydrocarbons and
water were collected. The entire hydrocarbon portion was
subsequently used as jet fuel without any purification or further
distillation.
Analysis of the Cellulosic Biomass-Derived Jet Fuel
[0655] The jet fuel produced by the method described above was
further analyzed for its carbon content and distribution. A
graphical depiction of the product distribution of aromatics,
alkenes, alkanes and oxygenates of various carbon content in the
jet fuel generated by the catalytic processing of biomass-derived
ethanol described herein is shown in FIG. 51. Based on the total
known components, the jet fuel contained about 25% of aromatic
hydrocarbons, about 2.5% of alkenes, about 41% of alkanes, and
about 8.5% of oxygenated compounds (wt./wt.). FIG. 51 also provides
a detailed breakdown of all the detectable compounds in the jet
fuel.
[0656] The unblended cellulosic biomass derived jet fuel was then
tested on a Rhino SE.RTM. series turbine from Jet Central. About
49% (w/w) of the jet fuel was blended with about 49% (w/w) of
Kerosene 1-K Heater Fuel from Kleanstrip.TM., and 2% (w/w) Torco
2-stroke GP-7 racing oil (as lubricant), and the turbine was run on
this fuel mixture. No operational or performance differences were
observerd in comparison to 98% (w/w) Kerosene 1-K Heater Fuel from
Kleanstrip.TM., and 2% (w/w) Torco 2-stroke GP-7 racing oil.
Generating Hydrocarbons from Blends of Longer Chain Alcohols
[0657] In another aspect, provided herein is a method of generating
hydrocarbons from blends of ethanol with longer chain alcohols,
branched chain alcohols, esters, aldehydes and ketones. It has been
found that higher yields can be obtained if, in addition to
ethanol, higher alcohols, branched alcohols, esters and ketones are
blended into the ethanol, for example, using greater that about 5%
(w/w), 10% (w/w), 15% (w/w), 20% (w/w), 30% (w/w), 40% (w/w) or 50%
(w/w) of the higher chain molecules. This can be particularly
useful when making heavier weight products such as kerosene, jet
fuel or diesel. Starting materials containing longer chains were
found to produce more higher molecular weight products.
[0658] For example, a composition of acetone, butanol ethanol (ABE)
was prepared by fermenting sugars derived from cellulosic material
with anaerobic bacteria (e.g., bacteria of the clostridium family
listed in paragaraphs 250, 267). The ABE composition contained
about 62.8% acetone (w/w), 29.1% butanol (w/w), and 8% ethanol
(w/w). This composition was catalytically converted to hydrocarbons
in the presence of 2.3 g of zeolite catalyst, HZSM-5. The
temperature was 350.degree. C., pressure was 500 Psi, N.sub.2 was
passed at a flow rate of 50 cc/min, and a liquid flow rate of
0.1875 cc/min. The resulting product was analyzed, and FIG. 52
provides a graphical description of the product distribution of
aromatics, alkenes, alkanes and oxygenates of various carbon
content in the hydrocarbon mixture generated by this process. The
graph shows the percentage amounts (vertical axis) of aromatics,
alkenes, alkanes and of oxygenates containing C2-C18 hydrocarbons
(horizontal axis) formed by the catalytic conversion of ABE. The
resulting hydrocarbon contained about 82.5% of aromatics, 2.9%
alkenes, 12.48% alkanes, and 7% of other compounds, included
oxygenated species. FIG. 52 also provides a detailed breakdown of
all the detectable compounds in the ABE composition.
[0659] The Examples disclosed in this application are to be
considered in all respects as illustrative and not limiting. Many
embodiments will be apparent to those of skill in the art upon
reading the above description. The scope of the invention should,
therefore, be determined not with reference to the above
description, but should instead be determined with reference to the
appended claims, along with the full scope of equivalents to which
such claims are entitled. The disclosures of all articles and
references, including patent applications, patents, and PCT
publications, are incorporated herein by reference for all
purposes.
* * * * *
References