U.S. patent application number 13/339553 was filed with the patent office on 2012-07-05 for catalytic biomass deconstruction.
Invention is credited to Randy D. Cortright, Dick A. Nagaki, Ming Qiao, Elizabeth Woods.
Application Number | 20120172588 13/339553 |
Document ID | / |
Family ID | 45531567 |
Filed Date | 2012-07-05 |
United States Patent
Application |
20120172588 |
Kind Code |
A1 |
Qiao; Ming ; et al. |
July 5, 2012 |
CATALYTIC BIOMASS DECONSTRUCTION
Abstract
The present invention provides processes for catalytically
converting biomass to oxygenated compounds suitable for use in
bioreforming processes.
Inventors: |
Qiao; Ming; (Pewaukee,
WI) ; Cortright; Randy D.; (Madison, WI) ;
Nagaki; Dick A.; (Woodland, TX) ; Woods;
Elizabeth; (Middleton, WI) |
Family ID: |
45531567 |
Appl. No.: |
13/339553 |
Filed: |
December 29, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61428454 |
Dec 30, 2010 |
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Current U.S.
Class: |
536/124 ;
549/464; 562/513; 568/861 |
Current CPC
Class: |
C07C 51/00 20130101;
C07D 307/46 20130101; C07C 45/55 20130101; B01J 23/42 20130101;
C10L 1/02 20130101; B01J 23/462 20130101; C07C 29/00 20130101; C10L
1/026 20130101; C07C 29/132 20130101; C10G 2300/1011 20130101; C10G
2300/44 20130101; C10G 2300/1014 20130101; Y02P 30/20 20151101;
C10G 2300/4081 20130101; C13K 1/02 20130101; C10G 2300/202
20130101; C07C 27/04 20130101; B01J 31/10 20130101; C10G 2300/805
20130101; C07C 29/132 20130101; C07C 31/26 20130101; C07C 29/00
20130101; C07C 31/207 20130101 |
Class at
Publication: |
536/124 ;
549/464; 562/513; 568/861 |
International
Class: |
C07H 3/02 20060101
C07H003/02; C07C 51/00 20060101 C07C051/00; C07C 31/20 20060101
C07C031/20; C07C 31/22 20060101 C07C031/22; C07C 31/24 20060101
C07C031/24; C07D 493/04 20060101 C07D493/04; C07C 31/18 20060101
C07C031/18 |
Goverment Interests
FEDERAL FUNDING STATEMENT
[0002] This invention was made with government support under award
#70NANB7H7023, requisition #4700558 awarded by NIST through the ATP
program. The government has certain rights in the invention.
Claims
1. A method of converting a biomass slurry to lower molecular
weight oxygenated hydrocarbons, the method comprising:
catalytically reacting a biomass slurry comprising water and a
biomass component, with hydrogen and a heterogeneous deconstruction
catalyst at a deconstruction temperature and a deconstruction
pressure to produce an oxygenated hydrocarbon having a lower
molecular weight than the biomass component.
2. The method of claim 1 wherein the biomass component comprises at
least one member selected from the group including a cellulose,
lignocellulose, agricultural residue, wood material, an energy
crop, municipal solid waste, recycled fiber, corn stover, straw,
bagasse, switch grass, miscanthus, sorghum, and poplar.
3. The method of claim 1 wherein the heterogeneous deconstruction
catalyst comprises an acidic resin or a basic resin.
4. The method of claim 1 wherein the heterogeneous deconstruction
catalyst comprises a support and a member adhered to the support,
wherein the member is selected from the group consisting of Cu, Fe,
Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Mo, alloys thereof, and combinations
thereof.
5. The method of claim 4 wherein the heterogeneous deconstruction
catalyst further comprises one or more members selected from the
group consisting of Cu, Mn, Cr, Mo, B, W, V, Nb, Ta, Ti, Zr, Y, La,
Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al, Ga, In, Tl, Ce, alloys thereof,
and combinations thereof.
6. The method of claim 1 wherein the oxygenated hydrocarbon is
selected from the group consisting of a starch, a carbohydrate, a
polysaccharide, a disaccharide, a monosaccharide, a sugar, a sugar
alcohol, an alditol, an organic acid, a phenol, a cresol,
ethanediol, ethanedione, acetic acid, propanol, propanediol,
propionic acid, glycerol, glyceraldehyde, dihydroxyacetone, lactic
acid, pyruvic acid, malonic acid, a butanediol, butanoic acid, an
aldotetrose, tartaric acid, an aldopentose, an aldohexose, a
ketotetrose, a ketopentose, a ketohexose, a hemicellulose, a
cellulosic derivative, a lignocellulosic derivative, and a
polyol.
7. A method of converting a biomass slurry to lower weight
oxygenated hydrocarbons, the method comprising: extracting the
biomass slurry using hot water to produce a first liquid portion
and a first solid slurry portion; separating the first liquid
portion from the first solid slurry portion; catalytically reacting
the first solid slurry portion with hydrogen in the presence of a
heterogeneous deconstruction catalyst at a deconstruction
temperature and a deconstruction pressure to produce a second solid
slurry portion and a second liquid portion; separating the second
liquid portion from the second solid slurry portion; and obtaining
lower weight oxygenated hydrocarbons comprising a C.sub.2+O.sub.1+
hydrocarbon in a liquid phase from the first and second liquid
portion.
8. The method of claim 7 wherein the cellulosic slurry comprises at
least one member selected from the group including a cellulose,
lignocellulose, agricultural residue, wood material, energy crop,
municipal solid waste, recycled fiber, corn stover, straw, bagasse,
switch grass, miscanthus, sorghum, and poplar.
9. The method of claim 7 wherein the first liquid portion comprises
at least one member selected from the group consisting of a
saccharide and an extractive.
10. The method of claim 7 wherein the first solid slurry portion
comprises at least one member selected from the group consisting of
cellulose, hemicellulose, lignin, and ash.
11. The method of claim 7 wherein the heterogeneous deconstruction
catalyst comprises an acidic resin or a basic resin.
12. The method of claim 7 wherein the heterogeneous deconstruction
catalyst comprises a support and a member adhered to the support,
wherein the member is selected from the group consisting of Cu, Fe,
Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Mo, alloys thereof, and combinations
thereof.
13. The method of claim 12 wherein the heterogeneous deconstruction
catalyst further comprises one or more members selected from the
group consisting of Cu, Mn, Cr, Mo, B, W, V, Nb, Ta, Ti, Zr, Y, La,
Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al, Ga, In, Tl, Ce, alloys thereof,
and combinations thereof.
14. The method of claim 7 wherein the deconstruction temperature is
in the range of about 150.degree. C. to 350.degree. C.
15. The method of claim 7 wherein the deconstruction pressure is in
the range of about 150 psi to 2000 psi.
16. The method of claim 7 wherein the C.sub.2+O.sub.1+ hydrocarbon
is selected from the group consisting of a starch, a carbohydrate,
a polysaccharide, a disaccharide, a monosaccharide, a sugar, a
sugar alcohol, a alditol, an organic acid, a phenol, a cresol,
ethanediol, ethanedione, acetic acid, propanol, propanediol,
propionic acid, glycerol, glyceraldehyde, dihydroxyacetone, lactic
acid, pyruvic acid, malonic acid, a butanediol, butanoic acid, an
aldotetrose, tartaric acid, an aldopentose, an aldohexose, a
ketotetrose, a ketopentose, a ketohexose, a hemicellulose, a
cellulosic derivative, a lignocellulosic derivative, a polyol, a
diol, and a mono-oxygenated hydrocarbon.
17. A method of converting cellulosic slurry to water-soluble
oxygenated hydrocarbons comprising: extracting the cellulosic
slurry using an organosolv process to produce a first liquid
portion and a first solid slurry portion; separating the first
liquid portion from the first solid slurry portion; separating a
solvent from the first liquid portion; catalytically reacting the
first solid slurry portion with hydrogen in the presence of a
heterogeneous deconstruction catalyst at a deconstruction
temperature and a deconstruction pressure to produce a second solid
portion and a second liquid portion; separating the second liquid
portion from the second solid portion; and obtaining water-soluble
oxygenated hydrocarbons comprising a C.sub.2+O.sub.1+ hydrocarbon
in an aqueous liquid phase from the first and second liquid
portions.
18. The method of claim 17 further comprising recycling the solvent
back into the organosolv process.
19. The method of claim 17 wherein the cellulosic slurry comprises
at least one member selected from the group including a cellulose,
lignocellulose, agricultural residue, wood material, energy crop,
municipal solid waste, recycled fiber, corn stover, straw, bagasse,
switch grass, miscanthus, sorghum, and poplar.
20. The method of claim 17 wherein the first liquid portion
comprises at least one member selected from the group consisting of
a saccharide, an extractive, and lignin.
21. The method of claim 17 wherein the first solid portion
comprises at least one member selected from the group consisting of
cellulose, hemicellulose, lignin, and ash.
22. The method of claim 17 wherein the heterogeneous deconstruction
catalyst comprises an acidic resin.
23. The method of claim 17 wherein the heterogeneous deconstruction
catalyst comprises a support and a member adhered to the support,
wherein the member is selected from the group consisting of Cu, Fe,
Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Mo, alloys thereof, and combinations
thereof.
24. The method of claim 23 wherein the heterogeneous deconstruction
catalyst further comprises one or more members selected from the
group consisting of Cu, Mn, Cr, Mo, B, W, V, Nb, Ta, Ti, Zr, Y, La,
Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al, Ga, In, Tl, Ce, alloys thereof,
and combinations thereof.
25. The method of claim 17 wherein the deconstruction temperature
is in the range of about 80.degree. C. to 350.degree. C.
26. The method of claim 17 wherein the deconstruction pressure is
in the range of about 100 psi to 2000 psi.
27. The method of claim 17 wherein the C.sub.2+O.sub.1+ hydrocarbon
is selected from the group consisting of a starch, a carbohydrate,
a polysaccharide, a disaccharide, a monosaccharide, a sugar, a
sugar alcohol, a alditol, an organic acid, a phenol, a cresol,
ethanediol, ethanedione, acetic acid, propanol, propanediol,
propionic acid, glycerol, glyceraldehyde, dihydroxyacetone, lactic
acid, pyruvic acid, malonic acid, a butanediol, butanoic acid, an
aldotetrose, tartaric acid, an aldopentose, an aldohexose, a
ketotetrose, a ketopentose, a ketohexose, a hemicellulose, a
cellulosic derivative, a lignocellulosic derivative, and a polyol,
a diol, and a mono-oxygenated hydrocarbon.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/428,454 filed on Dec. 30, 2010.
TECHNICAL FIELD
[0003] The present invention is directed to catalysts and methods
for deconstructing and fractionating biomass using heterogeneous
catalysts.
BACKGROUND OF THE INVENTION
[0004] The increasing cost of fossil fuel and environmental
concerns have stimulated world-wide interest in developing
alternatives to petroleum-based fuels, chemicals, and other
products. Biomass materials are a possible renewable
alternative.
[0005] Lignocellulosic biomass includes three major components.
Cellulose, a primary sugar source for bioconversion processes,
includes high molecular weight polymers formed of tightly linked
glucose monomers. Hemicellulose, a secondary sugar source, includes
shorter polymers formed of various sugars. Lignin includes
phenylpropanoic acid moieties polymerized in a complex three
dimensional structure. The resulting composition of lignocellulosic
biomass is roughly 40-50% cellulose, 20-25% hemicellulose, and
25-35% lignin, by weight percent.
[0006] No cost-effective process currently exists for efficiently
converting cellulose, hemicellulose, and lignin to components
better suited for producing fuels, chemicals, and other products.
This is generally because each of the lignin, cellulose and
hemicellulose components demand distinct processing conditions,
such as temperature, pressure, catalysts, reaction time, etc. in
order to effectively break apart its polymer structure.
[0007] A need exists for a method for converting biomass to
oxygenated compounds suitable for bioreforming processes, such as
Aqueous-Phase Reforming (APR) and hydrodeoxygenation (HDO).
Ideally, the method would convert biomass to carbohydrates, such as
starches, saccharides, sugars and sugar alcohols, which are
desirable feedstock for bioreforming processes.
[0008] Existing methods for converting biomass to usable feedstock
are not sufficient to meet the growing needs of bioreforming
processes. Hot water extraction of hemicelluloses from biomass has
been well documented, but the sugars produced by hot water
extraction are unstable at high temperatures leading to undesirable
decomposition products. Therefore, the temperature of the water
used for hot water extraction is limited, which can reduce the
effectiveness of the hot water extraction.
[0009] Additionally, studies have shown that it is possible to
convert microcrystalline cellulose (MCC) to polyols using hot,
compressed water and a hydrogenation catalyst (Fukuoka & Dhepe,
2006; Luo et al., 2007; and Yan et al., 2006). Typical
hydrogenation catalysts include ruthenium or platinum supported on
carbon or aluminum oxide. However, these studies also show that
only low levels of MCC are converted with these catalysts.
Selectivity toward desired sugar alcohols is also low. Therefore, a
process for converting biomass to polyols for further processing to
fuels, chemicals, and other products would be beneficial.
[0010] APR and HDO are catalytic reforming processes that generate
hydrogen and hydrocarbons from oxygenated compounds derived from a
wide array of biomass. The oxygenated hydrocarbons include
starches, mono- and poly-saccharides, sugars, sugar alcohols, etc.
Various APR methods and techniques are described in U.S. Pat. Nos.
6,699,457; 6,964,757; 6,964,758; and 7,618,612 (all to Cortright et
al., and entitled "Low-Temperature Hydrogen Production from
Oxygenated Hydrocarbons"); U.S. Pat. No. 6,953,873 (to Cortright et
al., and entitled "Low-Temperature Hydrocarbon Production from
Oxygenated Hydrocarbons"); and U.S. Pat. Nos. 7,767,867 and
7,989,664 and U.S. Application Ser. No. 2011/0306804 (all to
Cortright, and entitled "Methods and Systems for Generating
Polyols"). Various APR and HDO methods and techniques are described
in U.S. Patent Application Ser. Nos. 2008/0216391; 2008/0300434;
and 2008/0300435 (all to Cortright and Blommel, and entitled
"Synthesis of Liquid Fuels and Chemicals from Oxygenated
Hydrocarbons"); U.S. Patent Application Ser. No. 2009/0211942 (to
Cortright, and entitled "Catalysts and Methods for Reforming
Oxygenated Compounds"); U.S. Patent Application Ser. No.
2010/0076233 (to Cortright et al., and entitled "Synthesis of
Liquid Fuels from Biomass"); International Patent Application No.
PCT/US2008/056330 (to Cortright and Blommel, and entitled
"Synthesis of Liquid Fuels and Chemicals from Oxygenated
Hydrocarbons"); and commonly owned co-pending International Patent
Application No. PCT/US2006/048030 (to Cortright et al., and
entitled "Catalyst and Methods for Reforming Oxygenated
Compounds"), all of which are incorporated herein by reference.
[0011] Biomass must be deconstructed to less complex oxygenated
compounds prior to use as feedstock for bioreforming processes.
There remains a need for cost-effective methods for separating
biomass into streams suitable for use in APR, HDO and other
bioreforming processes.
SUMMARY
[0012] The invention provides methods for converting a biomass
slurry to lower molecular weight oxygenated hydrocarbons. The
method generally involves catalytically reacting a biomass slurry
comprising water and a biomass component with hydrogen and a
heterogeneous deconstruction catalyst at a deconstruction
temperature and a deconstruction pressure to produce an oxygenated
hydrocarbon having a lower molecular weight than the biomass
component.
[0013] One aspect of the invention is the composition of the
biomass slurry. In one embodiment, the biomass component may be
cellulose, lignocelluloses, agricultural residues, wood materials,
energy crops, municipal solid waste, recycled fibers, corn stover,
straw, bagasse, switch grass, miscanthus, sorghum, and poplar.
[0014] The heterogeneous deconstruction catalyst is capable of
deconstructing biomass to form oxygenated hydrocarbons and/or
oxygenates. In one embodiment, the heterogeneous deconstruction
catalyst includes an acidic resin or a basic resin. The
heterogeneous deconstruction catalyst may also include a support
and a member selected from the group consisting of Cu, Fe, Ru, Ir,
Co, Rh, Pt, Pd, Ni, W, Mo, alloys thereof, and combinations
thereof. The heterogeneous deconstruction catalyst may include
these elements alone or combined with one or more Cu, Mn, Cr, Mo,
B, W, V, Nb, Ta, Ti, Zr, Y, La, Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al,
Ga, In, Tl, Ce, and combinations thereof. In one embodiment, the
deconstruction catalyst includes Ni, Ru, Ir, Pt, Pd, Rh, Co, or Mo
and at least one member selected from W, B, Pt, Sn, Ag, Au, Rh, Co,
and Mo.
[0015] The oxygenated hydrocarbons may include a starch, a
carbohydrate, a polysaccharide, a disaccharide, a monosaccharide, a
sugar, a sugar alcohol, an alditol, an organic acid, a phenol, a
cresol, ethanediol, ethanedione, acetic acid, propanol,
propanediol, propionic acid, glycerol, glyceraldehyde,
dihydroxyacetone, lactic acid, pyruvic acid, malonic acid, a
butanediol, butanoic acid, an aldotetrose, tartaric acid, an
aldopentose, an aldohexose, a ketotetrose, a ketopentose, a
ketohexose, a hemicellulose, a cellulosic derivative, a
lignocellulosic derivative, a polyol, a diol, or a
mono-oxygenate.
[0016] Another aspect of the invention is a method of converting a
biomass slurry to lower weight oxygenated hydrocarbons and/or
oxygenates. The method generally involves: (1) extracting the
biomass slurry using hot water to produce a first liquid portion
and a first solid slurry portion; (2) separating the first liquid
portion from the first solid slurry portion; (3) catalytically
reacting the first solid slurry portion with hydrogen in the
presence of a heterogeneous deconstruction catalyst at a
deconstruction temperature and a deconstruction pressure to produce
a second solid slurry portion and a second liquid portion; (4)
separating the second liquid portion from the second solid slurry
portion; and (5) obtaining lower weight oxygenated hydrocarbons
comprising a C.sub.2+O.sub.1+ hydrocarbon in a liquid phase from
the first and second liquid portion.
[0017] The biomass slurry may include a cellulose, lignocellulose,
agricultural residue, wood material, energy crop, municipal solid
waste, recycled fiber, corn stover, straw, bagasse, switch grass,
miscanthus, sorghum, and poplar. The first liquid portion may
include a saccharide and an extractive, and the first solid slurry
portion may include cellulose, hemicellulose, lignin, and ash.
[0018] The heterogeneous deconstruction catalyst includes an acidic
resin or a basic resin and may include a support and a member
adhered to the support selected from the group consisting of Cu,
Fe, Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Mo, alloys thereof, and
combinations thereof.
[0019] The deconstruction reaction is conducted at a temperature
and pressure suitable for deconstructing biomass. In one
embodiment, the deconstruction temperature is in the range of about
80.degree. C. to 350.degree. C. and the deconstruction pressure is
in the range of about 150 psi to 2000 psi.
[0020] The C.sub.2+O.sub.1+ oxygenated hydrocarbons may include a
starch, a carbohydrate, a polysaccharide, a disaccharide, a
monosaccharide, a sugar, a sugar alcohol, an alditol, an organic
acid, a phenol, a cresol, ethanediol, ethanedione, acetic acid,
propanol, propanediol, propionic acid, glycerol, glyceraldehyde,
dihydroxyacetone, lactic acid, pyruvic acid, malonic acid, a
butanediol, butanoic acid, an aldotetrose, tartaric acid, an
aldopentose, an aldohexose, a ketotetrose, a ketopentose, a
ketohexose, a hemicellulose, a cellulosic derivative, a
lignocellulosic derivative, a polyol, a diol, or a mono-oxygenated
hydrocarbon.
[0021] Another aspect of the invention is a method of converting
cellulosic slurry to water-soluble oxygenated hydrocarbons. The
method generally includes: (1) extracting the cellulosic slurry
using an organosolv process to produce a first liquid portion and a
first solid slurry portion; (2) separating the first liquid portion
from the first solid slurry portion; (3) separating a solvent from
the first liquid portion; (4) catalytically reacting the first
solid slurry portion with hydrogen in the presence of a
heterogeneous deconstruction catalyst at a deconstruction
temperature and a deconstruction pressure to produce a second solid
portion and a second liquid portion; (5) separating the second
liquid portion from the second solid portion; and (6) obtaining
water-soluble oxygenated hydrocarbons comprising a C.sub.2+O.sub.1+
hydrocarbon in an aqueous liquid phase from the first and second
liquid portions.
[0022] In one embodiment, the method further includes recycling the
solvent back into the organosolv process.
[0023] The biomass slurry may include a cellulose, lignocellulose,
agricultural residue, wood material, energy crop, municipal solid
waste, recycled fiber, corn stover, straw, bagasse, switch grass,
miscanthus, sorghum, and poplar. The first liquid portion may
include saccharides extractive, and lignen, and the first solid
slurry portion may include cellulose, hemicellulose, lignin, and
ash.
[0024] The heterogeneous deconstruction catalyst includes an acidic
resin or a basic resin and may include a support and a member
selected from the group consisting of Cu, Fe, Ru, Ir, Co, Rh, Pt,
Pd, Ni, W, Mo, alloys thereof, and combinations thereof.
[0025] The deconstruction reaction is conducted at a temperature
and pressure suitable for deconstructing biomass. In one
embodiment, the deconstruction temperature is in the range of about
80.degree. C. to 350.degree. C. and the deconstruction pressure is
in the range of about 100 psi to 2000 psi.
[0026] The C.sub.2+O.sub.1+ oxygenated hydrocarbons may include a
starch, a carbohydrate, a polysaccharide, a disaccharide, a
monosaccharide, a sugar, a sugar alcohol, an alditol, an organic
acid, a phenol, a cresol, ethanediol, ethanedione, acetic acid,
propanol, propanediol, propionic acid, glycerol, glyceraldehyde,
dihydroxyacetone, lactic acid, pyruvic acid, malonic acid, a
butanediol, butanoic acid, an aldotetrose, tartaric acid, an
aldopentose, an aldohexose, a ketotetrose, a ketopentose, a
ketohexose, a hemicellulose, a cellulosic derivative, a
lignocellulosic derivative, and a polyol, a diol, or a
mono-oxygenated hydrocarbon.
DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a flow diagram illustrating one embodiment of the
present invention.
[0028] FIG. 2 is a chart illustrating the conversion of 10%
cellulose to polyols at 260.degree. C. using an Ru--C catalyst and
a short soak time.
[0029] FIG. 3 is a chart illustrating the product yield in aqueous
fraction from MCC at 260.degree. C. using a Ru--C catalyst and a
short soak time.
[0030] FIG. 4 is a chart illustrating difference in conversion of
10% cellulose to polyols at 260.degree. C. using a Ru--C catalyst
for a short soak time and a longer soak time.
[0031] FIG. 5 is a chart illustrating the difference in product
yield in aqueous fraction from MCC at 260.degree. C. using a Ru--C
catalyst for a short soak time and a longer soak time.
[0032] FIG. 6 is a chart illustrating the conversion of 10%
cellulose to polyols at 260.degree. C. using various hydrogenolysis
catalysts.
[0033] FIG. 7 is a chart illustrating product yields resulting from
using various hydrogenolysis catalysts.
[0034] FIG. 8 is a chart illustrating the difference between
bagasse and MCC conversion using an Ru--C catalyst.
[0035] FIG. 9 is a chart illustrating the difference in product
yields between bagasse and MCC conversion using a Ru--C
catalyst.
[0036] FIG. 10 is a chart illustrating the conversion of 10%
bagasse to polyols using phosphoric acid, PSA and Amberlyst 70.
[0037] FIG. 11 is a chart illustrating the product yields from the
conversion of 10% bagasse to polyols using phosphoric acid, PSA and
Amberlyst 70.
[0038] FIG. 12 is a chart illustrating the results from the
conversion of bagasse at different particle sizes.
[0039] FIG. 13 is a chart illustrating the products yields from the
conversion of bagasse at different particle sizes.
[0040] FIG. 14 is a chart illustrating the results from the
conversion of 10% microcrystalline cellulose using various
catalysts at 260.degree. C.
[0041] FIG. 15 is a chart illustrating the product yields from the
conversion of 10% microcrystalline cellulose using various
catalysts at 260.degree. C.
[0042] FIG. 16 is a chart illustrating the results from the
conversion of corn fiber using various catalysts at variable
temperatures.
[0043] FIG. 17 is a chart illustrating the product yields from the
conversion of corn fiber using various catalysts at variable
temperatures.
[0044] FIG. 18 is a chart illustrating the results from the
conversion of various biomass slurries using various catalysts at
260.degree. C.
[0045] FIG. 19 is a chart illustrating the product yields from the
conversion of various biomass slurries using various catalysts at
260.degree. C.
[0046] FIG. 20 is a chart illustrating the results from the
conversion of 10% bagasse using various catalysts at 300.degree.
C.
[0047] FIG. 21 is a chart illustrating the oxygenated product
yields from the conversion of 10% bagasse using various catalysts
at 300.degree. C.
[0048] FIG. 22 is a chart illustrating the product yields from the
conversion of 10% bagasse using various catalysts at 300.degree.
C.
[0049] FIG. 23 is a chart illustrating the results from the
conversion of various biomass slurries using a nickel tungsten
carbide catalyst.
[0050] FIG. 24 is a chart illustrating the product yields from the
conversion of various biomass slurries using a nickel tungsten
carbide catalyst.
[0051] FIG. 25 is a flow diagram illustrating one embodiment of the
present invention employing a hot water extraction or a solvent
pretreatment step.
[0052] FIG. 26 is a chart illustrating the results from the
conversion of various biomass slurries using a variety of
catalysts.
[0053] FIG. 27 is a chart illustrating the deoxygenation level of
various biomass slurries using a variety of catalysts.
[0054] FIG. 28 is a chart illustrating the product yields from the
conversion of various biomass slurries using a variety of
catalysts.
[0055] FIG. 29 is a chart illustrating the results from the
conversion of various biomass slurries using a variety of catalysts
and the amount of carbon converted to the aqueous phase.
[0056] FIGS. 30A-B are charts illustrating the carbon conversion to
the aqueous phase at varying reaction hydrogen partial pressures
with microcrystalline cellulose.
[0057] FIG. 31 is a chart illustrating product selectivity at
varying reaction hydrogen partial pressures with microcrystalline
cellulose.
[0058] FIG. 32 is a chart illustrating the degree of oxygenation at
varying reaction hydrogen partial pressures with microcrystalline
cellulose.
[0059] FIGS. 33A-B are charts illustrating the overall balances and
biomass conversion results of loblolly pine deconstruction at
varying temperatures and pressures.
DETAILED DESCRIPTION OF THE INVENTION
[0060] The present invention relates to methods, reactor systems,
and catalysts for converting biomass to less complex oxygenated
hydrocarbons for use in downstream bioreforming processes to
produce biofuels and chemicals. The invention includes methods of
converting biomass to lignin and lignocellulosic derivatives,
cellulose and cellulosic derivatives, hemicellulose and
hemicellulosic derivatives, carbohydrates, starches,
polysaccharides, disaccharides, monosaccharides, sugars, sugar
alcohols, alditols, polyols, diols, mono-oxygenated hydrocarbons,
and mixtures thereof, using hydrogen and a heterogeneous
catalyst.
[0061] As used herein, the term "biomass" refers to, without
limitation, organic materials produced by plants (such as leaves,
roots, seeds and stalks), and microbial and animal metabolic
wastes. Common biomass sources include: (1) agricultural residues,
including corn stover, straw, seed hulls, sugarcane leavings,
bagasse, nutshells, cotton gin trash, and manure from cattle,
poultry, and hogs; (2) wood materials, including wood or bark,
sawdust, timber slash, and mill scrap; (3) municipal solid waste,
including recycled fiber, waste paper and yard clippings; and (4)
energy crops, including poplars, willows, switch grass, miscanthus,
sorghum, alfalfa, prairie bluestream, corn, soybean, and the like.
The term also refers to the primary building blocks of the above,
namely, lignin, cellulose, hemicellulose and carbohydrates, such as
saccharides, sugars and starches, among others.
[0062] As used herein, the term "bioreforming" refers to, without
limitation, processes for catalytically converting biomass and
other carbohydrates to lower molecular weight hydrocarbons and
oxygenated compounds, such as alcohols, ketones, cyclic ethers,
esters, carboxylic acids, aldehydes, diols and other polyols, using
aqueous phase reforming, hydrogenation, hydrogenolyis,
hydrodeoxygenation and/or other conversion processes involving the
use of heterogeneous catalysts. Bioreforming also includes the
further catalytic conversion of such lower molecular weight
oxygenated compounds to C.sub.4+ compounds.
[0063] In the present invention, biomass is converted to a biomass
hydrolyzate using hydrogen and a heterogeneous deconstruction
catalyst. The general process is illustrated in FIG. 1. A biomass
slurry is created by combining biomass that has been chopped,
shredded, pressed, ground or processed to a size amenable for
conversion, with water and/or a solvent. The biomass slurry is then
passed into a reactor where it reacts with hydrogen and a
deconstruction catalyst at a deconstruction temperature and a
deconstruction pressure to produce oxygenated hydrocarbons that can
be used in downstream bioreforming processes or converted directly
to C.sub.4+ hydrocarbons, such as C.sub.4+ alkanes, C.sub.4+
alkenes, and aromatic compounds.
[0064] In one embodiment, illustrated in FIG. 25, the present
invention may also include an initial pretreatment hot water or
solvent-based extraction step. The hot water extraction or solvent
based process produces a liquid phase slurry and a solid phase
slurry. The liquid phase includes hemicellulose, lignin,
saccharides and extractives. If a solvent-based process is used,
the liquid phase also includes solvent, which can be separated from
the liquid phase and recycled for re-use. The solid phase slurry
includes the remaining cellulose, hemicellulose, lignin, and ash.
In this embodiment, the process generally involves: (1) extracting
the biomass slurry using hot water or the solvent to produce a
first liquid portion and a first solid slurry portion; (2)
separating the first liquid portion from the first solid slurry
portion; (3) catalytically reacting the first solid slurry portion
with hydrogen in the presence of a heterogeneous deconstruction
catalyst at a deconstruction temperature and a deconstruction
pressure to produce a second solid slurry portion and a second
liquid portion; (4) separating the second liquid portion from the
second solid slurry portion; and (5) obtaining from the first and
second liquid portion, lower weight oxygenated hydrocarbons (e.g.,
C.sub.2+O.sub.1+ oxygenated hydrocarbons). If a solvent is used,
the liquid phase can be separated from the solid phase slurry to
recover the solvent using known separation procedures.
[0065] Solvent-based applications are well known in the art.
Organosolv processes use organic solvents such as ionic liquids,
acetone, ethanol, 4-methyl-2-pentanone, and solvent mixtures, to
fractionate lignocellulosic biomass into cellulose, hemicellulose,
and lignin streams (Paszner 1984; Muurinen 2000; and Bozell 1998).
Strong-acid processes use concentrated hydrochloric acid,
phosphoric acid, sulfuric acid or other strong organic acids as the
depolymerization agent, while weak acid processes involve the use
of dilute strong acids, acetic acid, oxalic acid, hydrofluoric
acid, or other weak acids as the solvent. Enzymatic processes have
also recently gained prominence and include the use of enzymes as a
biocatalyst to decrystallize the structure of the biomass and allow
further hydrolysis to useable feedstocks.
[0066] If a solvent is used, once the solvent is recovered, the
resulting liquid phase slurry (absent a significant portion of the
solvent) can be recycled into the biomass slurry, recombined with
the solid phase slurry, used in a bioreforming process or,
alternatively, used as a feedstock for other conversion processes,
including the production of fuels and chemicals using fermentation
or enzymatic technologies.
[0067] The biomass slurry, solid phase slurry or combined
liquid/solid phase slurry is reacted with hydrogen over a
deconstruction catalyst under conditions of temperature and
pressure effective to cause a reaction that converts a portion of
the lignin, cellulose and hemicellulose to a biomass product stream
that includes less complex oxygenated compounds, extractives and
other inorganic products. The oxygenated compounds--referred to as
the biomass hydrolyzate--will generally include carbohydrates,
starches, polysaccharides, disaccharides, monosaccharides, sugars,
sugar alcohols, alditols, monooxygenates, organic acids, phenols,
and cresols. Preferably, the biomass hydrolyzate includes sugar,
sugar alcohols, starch, saccharides and other polyhydric alcohols.
More preferably, the biomass hydrolyzate includes a sugar, such as
glucose, fructose, sucrose, maltose, lactose, mannose or xylose, or
a sugar alcohol, such as arabitol, erythritol, glycerol, isomalt,
lactitol, malitol, mannitol, sorbitol, xylitol, arabitol, or
glycol. In certain embodiments, the biomass hydrolyzate may also
include alcohols, ketones, cyclic ethers, esters, carboxylic acids,
aldehydes, diols and other polyols that may be useful as an
organosolv-like solvent. In other embodiments, the biomass
hydrolyzate may also include mono-oxygenated hydrocarbons that may
be further converted to C.sub.4+ hydrocarbons, such as C.sub.4+
alkanes, C.sub.4+ alkenes, and aromatic compounds, including
benzene, toluene, xylene, which are useful as liquid fuels and
chemicals. Extractives will typically include ash, terpenoids,
stilbenes, flavonoids, proteins, etc. The product stream may also
include unreacted or under-reacted biomass.
[0068] The resulting biomass hydrolyzate may be collected for
further processing in a bioreforming process or, alternatively,
used as a feedstock for other conversion processes, including the
production of fuels and chemicals using fermentation or enzymatic
technologies. For example, water-soluble carbohydrates, such as
starch, monosaccharides, disaccharides, polysaccharides, sugars,
and sugar alcohols, and water-soluble derivatives from the lignin,
hemicellulose and cellulose are suitable for use in bioreforming
processes. Alternatively, the resulting biomass hydrolyzate may be
recycled and combined in the biomass slurry for further
conversion.
[0069] In certain applications, the biomass product stream
undergoes one or more separation steps to separate the extractives,
unreacted biomass and under-reacted biomass from the product stream
to provide the biomass hydrolyzate. The biomass hydrolyzate may
also require further processing to separate aqueous phase products
from organic phase products, such as lignin-based hydrocarbons that
are not suitable for further conversion. The biomass hydrolyzate
may also be dewatered or further purified prior to being introduced
into further processing steps. Such dewatering and purification
processes are known in the art and can include simulated moving bed
technology, distillation, filtration, etc.
[0070] The deconstruction catalyst is a heterogeneous catalyst
having one or more materials capable of catalyzing a reaction
between hydrogen and lignin, cellulose, hemicellulose and their
derivatives to produce the desired oxygenated compounds. The
heterogeneous deconstruction catalyst may include, without
limitation, acid modified resin, base modified resin, and/or one or
more of Cu, Fe, Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Mo, alloys and
combinations thereof. The deconstruction catalyst may include these
elements alone or combined with one or more Cu, Mn, Cr, Mo, B, W,
V, Nb, Ta, Ti, Zr, Y, La, Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al, Ga,
In, Tl, Ce, and combinations thereof. In one embodiment, the
deconstruction catalyst includes Ni, Ru, Ir, Pt, Pd, Rh, Co, or Mo
and at least one member selected from W, B, Pt, Sn, Ag, Au, Rh, Co,
and Mo.
[0071] Resins will generally include basic or acidic supports
(e.g., supports having low isoelectric points) that are able to
catalyze deconstruction reactions of biomass, followed by
hydrogenation reactions in the presence of H.sub.2, leading to
carbon atoms that are not bonded to oxygen atoms. Heteropolyacids
are a class of solid-phase acids exemplified by such species as
H.sub.3+xPMo.sub.12-xV.sub.xO.sub.40, H.sub.4SiW.sub.12O.sub.40,
H.sub.3PW.sub.12O.sub.40, and H.sub.6P2W.sub.18O.sub.62.
Heteropolyacids also have a well-defined local structure, the most
common of which is the tungsten-based Keggin structure. Basic
resins include resins that exhibit basic functionality, such as
Amberlyst.
[0072] The deconstruction catalyst is either self-supporting or
includes a supporting material. The support may contain any one or
more of nitride, carbon, silica, alumina, zirconia, titania,
tungsten, vanadia, ceria, zinc oxide, chromia, boron nitride,
tungstated zirconia, heteropolyacids, kieselguhr, hydroxyapatite,
and mixtures thereof. Preferable supports are carbon, m-ZrO.sub.2,
and W--ZrO.sub.2. In one embodiment, the deconstruction catalyst
includes Ni:Mo, Pd:Mo, Rh:Mo, Co:Mo, Pd:Ru, Pt:Re, or PtRh on a
m-ZrO.sub.2 support. In another embodiment, the deconstruction
catalyst includes Ru, Ru:Pt, Pd:Ru, Pt:Re, Pt:Rh, Pd:Mo, Pd:Ag, or
Ru:Pt:Sn on a carbon or W--ZrO.sub.2 support. In yet another
embodiment the deconstruction catalyst includes Fe, Co, Ni, Cu, Ru,
Rh, Pd, Pt, Re, Mo, or W on a carbon support. The support may also
serve as a functional catalyst, such as in the case of acidic or
basic resins or supports having acidic or basic functionality.
[0073] In one embodiment, the deconstruction catalyst is formed in
a honeycombed monolith design such that the biomass slurry, solid
phase slurry or the solid/liquid phase slurry can flow through the
deconstruction catalyst. In another embodiment, the deconstruction
catalyst includes a magnetic element such as Fe or Co such that the
deconstruction catalyst can be easily separated from the resulting
product mixture.
[0074] The biomass slurry, solid phase slurry or the solid/liquid
phase slurry is reacted with hydrogen over the deconstruction
catalyst under conditions of temperature and pressure effective to
convert cellulose and hemicellulose to polyols, monooxygenates,
organic acids, cyclic, phenols, and inorganics. The specific
products produced will depend on various factors, including the
composition of the slurry, reaction temperature, reaction pressure,
water concentration, hydrogen concentration, the reactivity of the
catalyst, and the flow rate of the slurry as it affects the space
velocity (the mass/volume of reactant per unit of catalyst per unit
of time), gas hourly space velocity (GHSV), and weight hourly space
velocity.
[0075] The deconstruction process can be either batch or
continuous. In one embodiment, the deconstruction process is a
continuous process using one or more continuous stirred-tank
reactors in parallel or in series. The deconstruction temperature
will generally be greater than 80.degree. C., or 120.degree. C., or
150.degree. C., or 180.degree. C., or 200.degree. C., or
250.degree. C., and less than 350.degree. C., or 325.degree. C., or
300.degree. C., or 280.degree. C., or 260.degree. C. In one
embodiment, the deconstruction temperature is between about
80.degree. C. and 350.degree. C., or between about 150.degree. C.
and 350.degree. C., or between about 150.degree. C. and 300.degree.
C., or between about 200.degree. C. and 260.degree. C., or between
about 250.degree. C. and 300.degree. C. The deconstruction pressure
is generally greater than 100 psi, or 250 psi, or 300 psi, or 625
psi, or 900 psi, or 1000 psi, or 1200 psi, and less than 2000 psi,
or 1500 psi, or 1200 psi. In one embodiment, the deconstruction
temperature is between about 100 psi and 2000 psi, or between about
300 psi and 1500 psi, or between about 1000 psi and 1500 psi.
Preferably, the slurry contacts the deconstruction catalyst for
between approximately 5 minutes and 2 hours.
[0076] In general, the reaction should be conducted under
conditions where the residence time of the slurry over the catalyst
is appropriate to generate the desired products. For example, the
WHSV for the reaction may be at least about 0.1 gram of biomass per
gram of catalyst per hour, and more preferably the WHSV is about
0.1 to 40.0 g/g hr, including a WHSV of about 0.25, 0.5, 0.75, 1.0,
1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2,
2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5,
3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8,
4.9, 5.0, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40
g/g hr, and ratios between (including 0.83, 0.85, 0.85, 1.71, 1.72,
1.73, etc.).
[0077] The present invention is able to effectively convert the
biomass components to lower molecular weight oxygenated
hydrocarbons due to the presence of hydrogen in the system. The
hydrogen facilitates the reaction and conversion process by
immediately reacting with the various reaction intermediates and
the deconstruction catalyst to produce products that are more
stable and less subject to degradation. The hydrogen may be
generated in situ using aqueous phase reforming (in situ-generated
H.sub.2 or APR H.sub.2), whether in the biomass deconstruction
reactor or in downstream processes using the biomass hydrolyzate as
a feedstock, or a combination of APR H.sub.2, external H.sub.2 or
recycled H.sub.2, or just simply external H.sub.2 or recycled
H.sub.2. The term "external H.sub.2" refers to hydrogen that does
not originate from the biomass solution, but is added to the
reactor system from an external source. The term "recycled H.sub.2"
refers to unconsumed hydrogen which is collected and then recycled
back into the reactor system for further use. External H.sub.2 and
recycled H.sub.2 may also be referred to collectively or
individually as "supplemental H.sub.2." In general, the amount of
H.sub.2 added should maintain the reaction pressure within the
system at the desired levels, or increase the molar ratio of
hydrogen to carbon and/or oxygen in order to enhance the production
yield of certain reaction product types.
[0078] The deconstruction process may also include the introduction
of supplemental materials to the slurry to assist with the biomass
deconstruction or the further conversion of the oxygenated
compounds to products more suited for bioreforming processes.
Supplemental materials may include dopants, such as acetone,
gluconic acid, acetic acid, H.sub.2SO.sub.4 and
H.sub.3PO.sub.4.
[0079] The deconstruction process converts the lignin, cellulose
and hemicellulose in the liquid and solid phase to an organic
complex including carbohydrates, starches, polysaccharides,
disaccharides, monosaccharides, sugars, sugar alcohols, alditols,
mono-oxygenates, organic acids, phenols, and cresols. In certain
applications, the biomass product stream undergoes one or more
separation steps to separate the catalyst (if any), extractives and
unreacted biomass from the biomass hydrolyzate. The biomass
hydrolyzate may also require further processing to separate aqueous
phase products from organic phase products, such as lignin-based
hydrocarbons not suitable for bioreforming processes. The biomass
hydrolyzate may also be dewatered or further purified prior to
being introduced into the bioreforming process. Such dewatering and
purification processes are known in the art and can include
simulated moving bed technology, distillation, filtration, etc.
[0080] After separating the impurities, the product stream,
suitable for use in bioreforming processes, includes oxygenated
hydrocarbons. Oxygenated hydrocarbons may be any water-soluble
oxygenated hydrocarbon having two or more carbon atoms and at least
one oxygen atom (referred to herein as C.sub.2+O.sub.1+
hydrocarbons). Preferably, the oxygenated hydrocarbon has 2 to 12
carbon atoms (C.sub.2-12O.sub.1-11 hydrocarbon), and more
preferably 2 to 6 carbon atoms (C.sub.2-6O.sub.1-6 hydrocarbon),
and 1, 2, 3, 4, 5, 6, or more oxygen atoms. The oxygenated
hydrocarbon may also have an oxygen-to-carbon ratio ranging from
0.5:1 to 1.5:1, including ratios of 0.75:1.0, 1.0:1.0, 1.25:1.0,
1.5:1.0, and other ratios between. In one example, the oxygenated
hydrocarbon has an oxygen-to-carbon ratio of 1:1. Nonlimiting
examples of preferred water-soluble oxygenated hydrocarbons include
starches, carbohydrates, polysaccharides, disaccharides,
monosaccharides, sugars, sugar alcohols, alditols, organic acids,
phenols, cresols, ethanediol, ethanedione, acetic acid, propanol,
propanediol, propionic acid, glycerol, glyceraldehyde,
dihydroxyacetone, lactic acid, pyruvic acid, malonic acid,
butanediols, butanoic acid, aldotetroses, tartaric acid,
aldopentoses, aldohexoses, ketotetroses, ketopentoses, ketohexoses,
hemicelluloses, cellulosic derivatives, lignocellulosic
derivatives, polyols and the like. Preferably, the oxygenated
hydrocarbon includes starches, sugar, sugar alcohols, saccharides
and other polyhydric alcohols. More preferably, the oxygenated
hydrocarbon is a sugar, such as glucose, fructose, sucrose,
maltose, lactose, mannose or xylose, or a sugar alcohol, such as
arabitol, erythritol, glycerol, isomalt, lactitol, malitol,
mannitol, sorbitol, xylitol, ribitol, or glycol.
[0081] The product stream may also include smaller oxygenates, such
as alcohols, ketones, cyclic ethers, esters, carboxylic acids,
aldehydes, diols and other polyols, that may be further converted
to C.sub.4+ hydrocarbons, such as C.sub.4+ alkanes, C.sub.4+
alkenes, and aromatic compounds, including benzene, toluene,
xylene, using a bioreforming process. As used herein, "oxygenates"
generically refers to hydrocarbon compounds having 2 or more carbon
atoms and 1, 2 or 3 oxygen atoms (referred to herein as
C.sub.2+O.sub.1-3 hydrocarbons), such as alcohols, ketones,
aldehydes, furans, hydroxy carboxylic acids, carboxylic acids,
diols and triols. Preferably, the oxygenates have from 2 to 6
carbon atoms, or 3 to 6 carbon atoms. Alcohols may include, without
limitation, primary, secondary, linear, branched or cyclic C.sub.2+
alcohols, such as ethanol, n-propyl alcohol, isopropyl alcohol,
butyl alcohol, isobutyl alcohol, butanol, pentanol, cyclopentanol,
hexanol, cyclohexanol, 2-methyl-cyclopentanonol, heptanol, octanol,
nonanol, decanol, undecanol, dodecanol, and isomers thereof. The
ketones may include, without limitation, hydroxyketones, cyclic
ketones, diketones, acetone, propanone, 2-oxopropanal, butanone,
butane-2,3-dione, 3-hydroxybutan-2-one, pentanone, cyclopentanone,
pentane-2,3-dione, pentane-2,4-dione, hexanone, cyclohexanone,
2-methyl-cyclopentanone, heptanone, octanone, nonanone, decanone,
undecanone, dodecanone, methylglyoxal, butanedione, pentanedione,
diketohexane, and isomers thereof. The aldehydes may include,
without limitation, hydroxyaldehydes, acetaldehyde,
propionaldehyde, butyraldehyde, pentanal, hexanal, heptanal,
octanal, nonal, decanal, undecanal, dodecanal, and isomers thereof.
The carboxylic acids may include, without limitation, formic acid,
acetic acid, propionic acid, butanoic acid, pentanoic acid,
hexanoic acid, heptanoic acid, isomers and derivatives thereof,
including hydroxylated derivatives, such as 2-hydroxybutanoic acid
and lactic acid. The diols may include, without limitation,
ethylene glycol, propylene glycol, 1,3-propanediol, butanediol,
pentanediol, hexanediol, heptanediol, octanediol, nonanediol,
decanediol, undecanediol, dodecanediol, and isomers thereof. The
triols may include, without limitation, glycerol, 1,1,1
tris(hydroxymethyl)-ethane (trimethylolethane), trimethylolpropane,
hexanetriol, and isomers thereof. Furans and furfurals include,
without limitation, furan, tetrahydrofuran, dihydrofuran, 2-furan
methanol, 2-methyl-tetrahydrofuran, 2,5-dimethyl-tetrahydrofuran,
2-methyl furan, 2-ethyl-tetrahydrofuran, 2-ethyl furan,
hydroxylmethylfurfural, 3-hydroxytetrahydrofuran,
tetrahydro-3-furanol, 2,5-dimethyl furan,
5-hydroxymethyl-2(5H)-furanone,
dihydro-5-(hydroxymethyl)-2(3H)-furanone, tetrahydro-2-furoic acid,
dihydro-5-(hydroxymethyl)-2(3H)-furanone, tetrahydrofurfuryl
alcohol, 1-(2-furyl)ethanol, hydroxymethyltetrahydrofurfural, and
isomers thereof.
[0082] As for the unreacted solids, the deconstruction catalyst can
be recycled for re-use in upstream processes. The lignin, ash and
other extractives can be purged from the system and used in other
processes. For example, the lignin can be burned to provide process
heat, while the proteinaceous material can be used for animal feed
or as other products.
Example 1
[0083] A biomass slurry containing 10 wt % microcrystalline
cellulose (MCC) in water was prepared and converted to a biomass
hydrolyzate using ruthenium on a carbon support. Experiments were
conducted in a Parr reactor at 240.degree. C. and 260.degree. C.,
and at variable processing times of 10 and 20 minutes.
[0084] It was discovered that the thermal decomposition of the
sugar intermediates is minimized/avoided with the formation of the
more stable oxygenates that arise from the hydrogenolysis of the
saccharides and polysaccharides. The Ru--C catalyst and short soak
times at 260.degree. C. provided high conversion and sugar-polyol
yields, with 72% conversion of microcrystalline cellulose (MCC) and
a sugars-polyol yield of 48%. A high yield of sorbitol (27 g/g MCC)
was found with Ru/C catalyst as illustrated in FIGS. 2 and 3. The
mass balance was 94% and aqueous analytical balance was 72%.
[0085] The effectiveness of the longer reaction time (20 min vs. 10
min) is shown in FIGS. 4 and 5. The extended reaction enhanced both
the conversion and hydrogenolysis of the MCC.
Example 2
[0086] Several deconstruction catalysts were analyzed for their
ability to convert 10% MCC in water to sugars/polyols. Experiments
were conducted in a Parr reactor at 260.degree. C. for 10 minutes.
As illustrated in FIGS. 6 and 7, platinum improves cellulose
conversion and provokes higher extent hydrogenolysis.
Example 3
[0087] A biomass slurry containing 10 wt % bagasse was converted to
biomass hydrolyzate using the Ru/C catalyst as described in Example
1. Experiments were conducted in a Parr reactor at 245.degree. C.
and 260.degree. C. for 10 minutes. FIGS. 8 and 9 provide a
comparison of the conversion and product yields for bagasse versus
the MCC of Example 1.
Example 4
[0088] Acidic resins containing a sulfonate group were investigated
for their ability to hydrolyze bagasse using the catalytic
depolymerization techniques of the present invention. Soluble
polystyrene sulfonic acid (PSA) and phosphoric acid were used as
hydrolyzing acids for comparison. Ruthenium supported on carbon was
used as a hydrogenation catalyst. The detailed experimental
conditions are listed in Table 1.
TABLE-US-00001 TABLE 1 Study of acidity of acidic resin's
functional group H.sub.2 Bagasse Temp Time* Pressure Hydrogenation
Trial (wt %) Acid (.degree. C.) (min) (psi) Catalyst** 1 10 5%
H3PO4 190 90 500 1% Ru/C 2 10 5% PSA 190 90 500 1% Ru/C 3 10 1% PSA
190 90 500 1% Ru/C 4 10 0.25:1 190 90 500 1% Ru/C Amberlyst
70:Bagasse *Total time includes 30 minutes of heating **Catalyst
load is 0.3:1 catalyst:bagasse
[0089] The results of bagasse hydrolysis using phosphoric acid, PSA
and Amberlyst 70 are compared in FIGS. 10 and 11. Using 5% PSA
(Trial 2) achieved similar bagasse hydrolysis results as using 5%
H.sub.3PO.sub.4 (Trial 1), converting .about.40% bagasse into
sugars, polyols, organic acids, and a substantial amount of other
decomposition products. 1% PSA (Trial 3) converted less bagasse
than 5% homogeneous acids. The 1% PSA yielded a higher net
sugar/polyol yield because the 5% PSA caused more severe sugar
degradation. The "soluble homogeneous" acid catalysts had larger
yields of unknowns versus the solid acid catalyst, Amberlyst 70.
This is consistent with insufficient hydrogenation of the resulting
monomeric sugars to the more stable sugar alcohols that would
presumably prevent sugar degradation. The reduced hydrogenation
activity could be due to fouling of the hydrogenation catalyst with
the soluble PSA, decomposition products of the sugar, or
solubilized lignin. The Amberlyst 70 is a resin that has high
temperature stability of 190.degree. C., but the upper temperature
range for the soluble PSA is probably significantly lower. The
Amberlyst 70 remains intact as a heterogeneous solid acid and
therefore does not poison or cause fouling of the hydrogenation
catalyst. In the case of the 5% H.sub.3PO.sub.4, the hydrogen
phosphate or impurities present in the phosphoric acid (S, Ca, N,
etc.) might poison the hydrogenation catalyst.
[0090] When using the Amberlyst 70, xylitol is the major product
and sorbitol, arabitol, and acetic acid are the minor products.
These products result from depolymerization of hemicellulose which
accounts for 25% of the sugarcane bagasse used in this study. The
rest of the bagasse conversion (up to 40%) is primarily from
solubilized extractives and lignin. This is consistent with the
acid-catalyzed hydrolysis of hemicellulose, which involves
solubilization, hydrogenation and partial deconstruction of the
reducing sugars under these conditions. This is consistent with the
two-stage acid hydrolysis processes in which the first stage uses
dilute H.sub.2SO.sub.4 and has proven to be an efficient means of
producing xylose from hemicellulose (Roberto 1994; Silva 1996).
[0091] When using the soluble homogeneous acids, glucose, oxalic
acid and unknowns are the major components in the product mix.
Xylose, xylitol, arabitol, acetic acid, and formic acid are present
at lower levels. The results are consistent with the acid-catalyzed
hydrolysis of both hemicellulose and cellulose when more drastic
reaction conditions are employed. Glucose can be produced from
cellulose hydrolysis and xylose decomposes rapidly, resulting in
unidentified products. The product distribution is consistent with
the acid-catalyzed hydrolysis of hemicellulose, its partial
hydrogenation before the hydrogenation activity stopped, and
decomposition to unknowns of the non-hydrogenated sugars. The acid
hydrolysis of cellulose could have occurred in parallel or slightly
delayed to the hemicellulose hydrolysis due to the increased
difficulty to solubilize cellulose.
[0092] As a summary, soluble polystyrene sulfonic acid can convert
40% sugarcane bagasse at temperature of 190.degree. C., producing
sugars, polyols, organic acids and degradation products. The 12%
sugar/polyol yield is similar to using 5% phosphoric acid. This
indicates that polystyrene sulfonic acid has a high enough acidity
to hydrolyze biomass analogous to a similar concentration of
homogenous acid.
Example 5
[0093] Experiments were conducted to determine the impact of
biomass particle size on homogeneous and heterogeneous hydrolysis.
Ground sugarcane bagasse particles (<20, 40, 60 mesh, <840,
420, and 250 .mu.m, respectively) were used as representing
lignocellulosic material. Hot water extraction and hydrolysis using
acidic resin (Amberlyst 70) were used as representative homogeneous
and heterogeneous processes. The detailed experimental conditions
are listed in Table 2.
[0094] The results of hydrolysis using different bagasse particle
sizes are compared in FIGS. 12 and 13. Similar hydrolysis results
were observed among different bagasse particle sizes. Finer
particles facilitate bagasse conversion using heterogeneous
catalyst, but not significantly. Using a solid acid catalyst
enhances hemicellulose hydrolysis producing more xylose and glucose
than the water-only extraction. No significant increase of glucose
yield with decreasing bagasse particle size was achieved using
acidic resin, indicating that grinding bagasse to the smaller
particle sizes tested here does not expose more cellulose to solid
acids.
TABLE-US-00002 TABLE 2 Hydrolysis of sugarcane bagasse using
different bagasse particle sizes Bagasse Temp* Time** Analytical WC
(wt %) Acid (.degree. C.) (min) Hydrolysis 1 10 -- 170 120 3% 2 10
-- 170 120 H.sub.2SO.sub.4, 3 10 -- 170 120 120.degree. C., 60 min
4 10 0.25:1 Amberlyst 70 160 120 -- 5 10 0.25:1 Amberlyst 70 160
120 -- 6 10 0.25:1 Amberlyst 70 160 120 -- *Temperatures are
determined by previous studies providing most sugar/polyol yield
**Total time includes 60 minutes of heating
[0095] The results suggest that the mild reaction conditions used
here, i.e., relatively low temperature and short reaction time,
leads to limited bagasse conversion in all cases, and that the
Amberlyst resin case did better than water extraction only. High DP
oligosaccharides released from hemicellulose under high temperature
are hydrolyzed with in-situ acid hydrolysis. However, these big
molecular saccharides are not water-soluble after being cooled to
room temperature. This explains the lower sugar yield by water only
extraction with analytical hydrolysis.
Example 6
[0096] Four different deconstruction catalysts were investigated
for the conversion of microcrystalline cellulose. Platinum and
Ruthenium were selected as deconstruction catalysts. Activated
carbon, tungstated zirconia, and .alpha.-alumina were selected as
catalyst supports. Elevated temperature (260.degree. C.) and
H.sub.2 pressure (600 psi H.sub.2 initial reactor pressure), and
short reaction time (60 min heating and 10 min retention) were
applied to all experiments. The hydrogenolysis results are shown in
FIGS. 14 and 15.
[0097] Platinum supported on alumina, among the tested four
catalysts, gives the highest conversion of microcrystalline
cellulose into desired products. Ruthenium supported on activated
carbon demonstrated high microcrystalline cellulose conversion
(.about.70%) and polyol products yield (50%). This result indicates
that highly crystalline cellulose can be hydrolyzed at elevated
temperature and pressure using deconstruction catalyst with inert
support. Alumina support does not show major impacts on cellulose
hydrolysis given that conversion drops significantly when supported
catalytic metal is changed to ruthenium. When solid acid
(tungstenated zirconia) is applied as catalyst support, undesired
reactions (degradation and recondensation) lead to poor yield of
polyols and production of unidentified compounds.
[0098] FIG. 15 shows that major products from the deconstruction of
microcrystalline cellulose are polyols (from C.sub.2 to C.sub.6)
and other oxygenates. Ruthenium shows high capacity of
hydrogenation resulting in significant production of sorbitol.
Platinum shows good hydrogenolysis performance including both
deoxygenation and carbon-carbon bond cleavage. In summary, highly
efficient deconstruction of microcrystalline cellulose can be
achieved using deconstruction catalysts under elevated temperature
and pressure. Major products are polyols, organic acids, and
oxygenates, etc., that can be utilized in the bioreforming process
being developed by Virent, Inc. (Madison, Wis.).
Example 7
[0099] A 10 wt % corn fiber in water was hydrolyzed using various
catalysts and processing conditions. Three reaction conditions were
selected: (1) Amberlyst 70+Ru/C catalyst at 190.degree. C. and 600
psi H.sub.2, (2) Ru/C catalyst at 200.degree. C. and 600 psi
H.sub.2, and (3) Ru/C catalyst at 260.degree. C. and 600 psi
H.sub.2. The experimental results are shown in FIGS. 16 and 17.
[0100] It can be seen that using an acidic resin in this study,
improves corn fiber conversion. But reduced hydrogenation catalyst
activity can also be observed, especially under the elevated
temperature. This poor hydrogenation performance is understood to
be caused by impurities introduced by corn fiber hydrolysis, which
can be lignin, protein, and sugar decomposition products.
Example 8
[0101] Biomass deconstruction of various biomass samples was
explored using deconstruction catalysts containing ruthenium and
ruthenium/rhodium on carbon. Reaction conditions were 260.degree.
C. and >1000 psi H.sub.2. Results show that the catalysts are
able to convert 60-100% MCC, soda hardwood (Kappa 110) pulp, and
sugarcane bagasse. The major products are sugars/polyols and
decomposition products, such as furfurals, cyclic ethers, and
cracked lignin. The experimental results are shown in FIGS. 19 and
20. The Ru/C catalyst gives the highest yield of sorbitol. The
addition of rhodium significantly improved the biomass
conversion.
Example 9
[0102] A study was conducted on acid, base and metal functions of
various catalysts and their ability to convert bagasse to desired
compounds.
[0103] Zirconia catalysts were prepared by precipitation. A
solution of ZrOCl.sub.2 was added into ammonium hydroxide solution
(pH=10-11). The precipitate was dried at 70.degree. C. and then
rinsed to remove chloride ions.
[0104] WO.sub.3/ZrO.sub.2 and MgO/ZrO.sub.2 catalysts were prepared
by incipient wetting impregnation. Appropriate amounts of
precursors were dissolved in deionized water and evenly distributed
onto the ZrO.sub.2 supports. The wet catalysts were dried at
120.degree. C. in oven for at least 12 hours. Some materials were
calcined in air at 600.degree. C. for up to 4 hours. The catalyst
formulations that were tested are listed in Table 3 below.
TABLE-US-00003 TABLE 3 Catalyst Information Atomic Metal Catalyst
Ratios Loading wt % Note Hydrous zirconia -- -- Control Tungstate
zirconia W:Zr = 0.053 -- Acidity scoping Tungstate zirconia W:Zr =
0.106 -- Acidity scoping Magnesia zirconia Mg:Zr = 0.037 --
Basicity scoping Magnesia zirconia Mg:Zr = 10 -- Basicity scoping
Rh loaded zirconia -- 2.5% Rh Control Ni loaded zirconia -- 5% Ni
Control NiB loaded zirconia B:Ni = 0.037 5% Ni Rh alternative
[0105] All experiments were conducted using a 600 mL Parr reactor
using ground sugarcane bagasse (<20 mesh) as the lignocellulosic
biomass feed. The reactor was pre-pressurized with hydrogen at room
temperature. The operation conditions were the same for all
formulations and are shown in Table 4. Bagasse, catalyst, and the
proper amount of water were co-filled in a Parr reactor and were
well mixed by vigorous stirring (800 rpm) from the start of heating
to the end of cooling. Aqueous and solid samples were taken after
the deconstruction reaction was completed.
TABLE-US-00004 TABLE 4 Process conditions H.sub.2 Pre- Total Total
Charge Heating Retention Bagasse Bagasse Catalyst Temp Pressure
Time Time weight [g] [wt %] Load [g] [.degree. C.] [PSI] [min]
[min] 10.5 10 10 300 250 90 15
[0106] FIG. 20 shows the conversion of bagasse over the different
catalysts. Among the screened catalysts, 2.5% Ru, 2.5% Rh/ZrO.sub.2
catalyst gave the highest conversion of bagasse to non-solid
components (.about.85%), while the conversion was lowest for 5%
Ni/ZrO.sub.2 (.about.69%), which was identical to the control
experiment conversion when no catalyst was added. Using the hydrous
ZrO.sub.2 without any modification gave a conversion of
.about.76.5% suggesting that the Ni/ZrO.sub.2 catalyst underwent
rapid deactivation.
[0107] Two solid acid catalysts, 20% WO.sub.3/ZrO.sub.2 and 10%
WO.sub.3/ZrO.sub.2, were tested resulting in bagasse conversions of
76% and 81%, respectively. Similarly, .about.73% and .about.80%
conversion of bagasse were realized over two solid base catalysts,
1.2% MgO/ZrO.sub.2 and 327% MgO/ZrO.sub.2, respectively, indicating
that the basicity of the catalyst also contributes to the biomass
depolymerization. Again the 20% WO.sub.3/ZrO.sub.2 and 1.2%
MgO/ZrO.sub.2 had lower reactivity than the ZrO.sub.2 support
alone. This can be explained by the bifunctional nature of the
hydrous ZrO.sub.2, possessing acidic and basic sites, which both
contribute to the catalytic deconstruction of bagasse. FIG. 20 also
compares the bagasse conversion over 2.5% Rh/ZrO.sub.2 with that
over its alternative, 5% Ni, 0.34% B/ZrO.sub.2 showing that the
conversions are almost the same, .about.82% for the two
catalysts.
[0108] Carboxylic acids, sugars or polyols, and other oxygenates,
including alcohols and hydroxyl ketones, are the main products that
can be identified with current analytic capability. For the
catalysts screened, the yields of total carboxylic acids are
significantly higher than other aqueous products as shown in FIG.
21. Amongst the screened catalysts, 20% WO.sub.3/ZrO.sub.2 gave the
highest acid yield, while 327% MgO/ZrO.sub.2 gives the highest
yield of the sugar/polyol products. Unidentified components
comprise over 70% of the carbon in the aqueous products for each
hydrolyzate, and these could be partially reduced polyols,
large-molecular weight oligomers, lignin derivatives, etc. With
such a large amount of unidentified components, it is difficult to
determine how the different functionalities of the catalysts affect
the bulk production distribution. However, it is hypothesized that
a liquefied biomass product of comparable composition will be
compatible with the downstream bioreforming process. A more
detailed product distribution is shown in FIG. 22.
[0109] In summary, WO.sub.3, MgO, and metal modified ZrO.sub.2
catalysts with acid, base, and metal functions, respectively were
tested for deconstruction of sugarcane bagasse. With appropriate
formulations, more than 80% conversion can be obtained over 10%
WO.sub.3/ZrO.sub.2, 327% MgO/ZrO.sub.2, or 5% Ni, 0.34% B/ZrO.sub.2
catalyst, suggesting each function including acid hydrolysis, base
catalysis or metal hydrogenolysis can individually contribute to
the lignocellulosic biomass deconstruction.
Example 10
[0110] This study was to validate the conversion of cellulose,
hemicellulose and sugarcane bagasse using nickel-promoted tungsten
carbide, to achieve high cellulose conversion and high polyols
yield. Nickel-promoted tungsten carbide catalyst was prepared with
the composition listed in Table 5.
TABLE-US-00005 TABLE 5 Composition of nickel-promoted tungsten
carbide catalyst Catalyst Composition Metal 1 2% Ni Metal 2 30%
W.sub.2C Support RX3 Extra Carbon
[0111] Microcrystalline cellulose, ground sugarcane bagasse (<20
mesh) and hemicellulose (xylan) were used as representing
cellulosic materials. All experiments were conducted using Parr
reactor under a static H.sub.2 atmosphere. The reaction temperature
and residence time were major variables to be controlled. The
reactor was pressurized with hydrogen to a desired pressure at room
temperature prior to heating. The detailed experimental conditions
are listed in Table 6.
TABLE-US-00006 TABLE 6 Conversion of cellulosic biomass using
nickel tungsten carbide catalyst Ni--W.sub.2C/AC H.sub.2 Feedstock
Water (Dry wt. Pressure Temp Time* WC (Dry wt.) (g) g) (psi) (C.)
(min) 1 1 g MCC 100 0.3 870 245 120 2 1 g Bagasse 100 0.3 870 245
120 3 1 g Xylan 100 0.3 870 245 120 4 10 g 100 1 870 245 120
Bagasse *Total time includes 90 minutes heating time
[0112] FIGS. 23 and 24 show the overall results and product
distribution of cellulosics conversion over nickel tungsten carbide
catalyst. At low biomass concentration (1%), 95% of
microcrystalline cellulose, 93% of hemicellulose and 78% of bagasse
were converted to polyols, organic acids, and other sugar
degradation products. The major products are ethylene glycol,
propylene glycol and acetol. The high 60% ethylene glycol yield
reported by Zhang and Chen was not achieved. This could be caused
by different catalyst composition or larger scale reactor leading
to different mass and heat transfer.
[0113] Pure carbohydrates gave higher yields of desired products as
compared with bagasse. The detrimental effect of lignin, ash and/or
extractives released from bagasse is observed in the bagasse runs.
The used catalyst surface of the 10% bagasse run appeared to have a
shiny coat, possibly due to glassified lignin or decomposition
products.
[0114] FIG. 24 shows that sugars or polyols were decomposed to
organic acids and other degradation products such as HMF and
furfurals that are included in the unknowns.
Example 11
[0115] A study was conducted to show the ability of a variety of
catalysts to liquefy a variety of types of biomass and to convert
that biomass to a wide range of products including many highly
deoxygenated products. Microcrystalline cellulose and corn stover
were deconstructed using water, hydrogen, and various metals on
oxide supports. All experiments were conducted under a static
H.sub.2 atmosphere. The detailed experimental conditions are listed
in Table 7.
TABLE-US-00007 Feedstock H.sub.2 (slurry 10 wt Pressure Temp Time*
WC % solids) Catalyst (psi) (C.) (min) 1 Cellulose 2% Pd 2% Ru, 8%
W 1250 300 100 m-ZrO2 2 Corn Stover 2% Pt 2% Re, m-ZrO2 1250 300
100 3 Corn Stover 2% Pd 0.5% Rh, m-ZrO2 1250 300 100 4 Corn Stover
2% Pd 2% Mo, W 1250 300 100 m-ZrO2 *Total time includes 90 minutes
heating time
[0116] FIG. 26 shows that 80 to 100% of the biomass feedstock was
converted. FIG. 27 shows the deoxygenation levels from the
catalytic deconstruction indicating promising selectivity to mono
and poly-oxygenates. FIG. 28 shows the product yields of the
deconstruction. FIG. 29 shows the overall conversion and the carbon
that is converted in the aqueous phase.
Example 12
[0117] A study was conducted on the effect of hydrogen partial
pressure on the deconstruction of microcrystalline cellulose using
water, hydrogen and a metal oxide hydrodeoxygenation catalyst. (2%
Pd 2% Ag/W--ZrO2)
[0118] A slurry having a concentration of 10 wt % solids in water
was reacted for a 90 minute heating period at a temperature of
280.degree. C. and varying starting partial pressures of hydrogen
from 0 to 500 psi. All of the runs were pre-pressurized to the same
level. Nitrogen was added as an inert for the runs with lower
partial pressures of hydrogen in order to maintain the aqueous
phase reaction of the cellulose.
[0119] FIGS. 30 and 31 show the ability of the catalysts to convert
most of the cellulose to the aqueous phase and selectively to a
wide range of products, many of which are highly deoxygenated. FIG.
30-B shows the amount of carbon put into the system from the
cellulosic feed and converted into the aqueous phase. FIG. 32 shows
the level of deoxygenation in the products at each of the varying
partial pressures of hydrogen. The general trend observed shows
that as hydrogen availability is increased, the deoxygenation
increases and the amount of carbon converted into the aqueous phase
increases.
Example 13
[0120] A study was conducted on the effect of temperature and
hydrogen partial pressure on the deconstruction of loblolly pine
and using water, hydrogen and a metal oxide hydrodeoxygenation
catalyst. (2% Pd 2% Ag/W--ZrO2)
[0121] A slurry having a concentration of 10 wt % solids in water
was reacted for a 90 minute heating period at varying temperatures
of 240-300.degree. C. and pressures of hydrogen from 1000-1450 psi.
All of the runs were pre-pressurized to a level that would ensure
the aqueous phase reaction of the lignocellulose.
[0122] Temperature plays a large role into the conversion of
feedstock to products, particularly to oxygenates. More of the
feedstock is converted with increased temperatures, but it is
converted to a greater amount of unknown compounds. Increasing the
reaction time decreases the amount of carbon that remains in the
aqueous phase, indicating greater losses to the gas phase and
degradation through condensation of products on the catalyst and
reactor. FIGS. 33A and 33B show the mass and analytical balances
and biomass conversion results of loblolly pine deconstruction at a
variety of temperatures and pressures.
* * * * *