U.S. patent application number 13/677124 was filed with the patent office on 2013-05-16 for process for conversion of a cellulosic material.
This patent application is currently assigned to SHELL OIL COMPANY. The applicant listed for this patent is Shell Oil Company. Invention is credited to Andries Quirin Maria BOON, Leticia ESPINOSA ALONSO, Johan Willem GOSSELINK, John William HARRIS, Andries Hendrik JANSSEN, Jean Paul LANGE, Colin John SCHAVERIEN, Nicolaas Wilhelmus Joseph WAY.
Application Number | 20130118059 13/677124 |
Document ID | / |
Family ID | 47215545 |
Filed Date | 2013-05-16 |
United States Patent
Application |
20130118059 |
Kind Code |
A1 |
LANGE; Jean Paul ; et
al. |
May 16, 2013 |
PROCESS FOR CONVERSION OF A CELLULOSIC MATERIAL
Abstract
A process for conversion of a cellulosic material comprising a)
a liquefaction step, comprising contacting a cellulosic material
with a liquid solvent at a temperature of equal to or more than
200.degree. C.; or contacting a cellulosic material with a liquid
solvent at a temperature of equal to or more than 100.degree. C. in
the presence of a catalyst, to produce a final liquefied product;
b) a catalytic cracking step, comprising contacting at least part
of the final liquefied product with a fluidized catalytic cracking
catalyst at a temperature of equal to or more than 400.degree. C.,
to produce one or more cracked products.
Inventors: |
LANGE; Jean Paul;
(Amsterdam, NL) ; SCHAVERIEN; Colin John;
(Amsterdam, NL) ; WAY; Nicolaas Wilhelmus Joseph;
(Amsterdam, NL) ; GOSSELINK; Johan Willem;
(Amsterdam, NL) ; HARRIS; John William;
(Amsterdam, NL) ; BOON; Andries Quirin Maria;
(Amsterdam, NL) ; JANSSEN; Andries Hendrik;
(Amsterdam, NL) ; ESPINOSA ALONSO; Leticia;
(Amsterdam, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shell Oil Company; |
Houston |
TX |
US |
|
|
Assignee: |
SHELL OIL COMPANY
Houston
TX
|
Family ID: |
47215545 |
Appl. No.: |
13/677124 |
Filed: |
November 14, 2012 |
Current U.S.
Class: |
44/307 |
Current CPC
Class: |
Y02P 30/20 20151101;
C10G 1/002 20130101; C10G 1/006 20130101; C10G 3/50 20130101; C10G
11/18 20130101; C10L 1/02 20130101; C10G 1/042 20130101 |
Class at
Publication: |
44/307 |
International
Class: |
C10G 1/00 20060101
C10G001/00; C10L 1/02 20060101 C10L001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2011 |
EP |
EP11189049.7 |
Oct 25, 2012 |
EP |
EP12190054.2 |
Claims
1. A method for conversion of a cellulosic material comprising a
liquefaction step to produce a final liquefied product, the
liquefaction step comprising: contacting a cellulosic material with
a liquid solvent at a temperature of equal to or more than about
200.degree. C.; or contacting a cellulosic material with a liquid
solvent at a temperature of equal to or more than about 100.degree.
C. in the presence of a catalyst; and a catalytic cracking step to
produce at least one cracked product, the catalytic cracking step
comprising contacting at least part of the final liquefied product
with a fluidized catalytic cracking catalyst at a temperature of
equal to or more than about 400.degree. C.
2. The method of claim 1, wherein the liquid solvent comprises
water and/or an organic solvent.
3. The method of claim 1, wherein the liquefaction step comprises
simultaneously contacting the cellulosic material with an organic
solvent, a source of hydrogen, an acid catalyst and a hydrogenation
catalyst at a temperature of equal to or more than about
150.degree. C.
4. The method of claim 1, wherein the liquefaction step comprises
contacting the cellulosic material with an organic solvent in the
presence of an acid catalyst at a temperature of equal to or more
than about 150.degree. C. to produce an intermediate liquefied
product; and subsequently hydrotreating the intermediate liquefied
product with a source of hydrogen in the presence of a
hydrotreatment catalyst to produce a final liquefied product.
5. The method of claim 1, wherein the liquid solvent is an organic
solvent and wherein the process further comprises a separation
step, wherein at least a portion of the final liquefied product
produced in the liquefaction step is separated from at least part
of the organic solvent.
6. The method of claim 5 wherein the separated portion of the
organic solvent is used in the liquefaction step.
7. The method of claim 1, wherein the catalytic cracking step
comprises contacting at least part of the final liquefied product
and a fluid hydrocarbon co-feed with the fluidized catalytic
cracking catalyst at a temperature of equal to or more than about
400.degree. C.
8. The method of claim 7, wherein the fluid hydrocarbon co-feed
comprises at least one of a straight run (atmospheric) gas oil, a
flashed distillate, a vacuum gas oil (VGO), a light cycle oil, a
heavy cycle oil, a hydrowax, a coker gas oil, a gasoline, a
naphtha, a diesel, a kerosene, an atmospheric residue ("long
residue"), a vacuum residue ("short residue"), and any combination
thereof.
9. The method of claim 1, wherein the liquefaction step comprises
contacting a cellulosic material with an organic solvent at a
temperature of equal to or more than about 100.degree. C. in the
presence of a catalyst, wherein the organic solvent comprises a
fraction of a petroleum oil; and wherein the catalytic cracking
step comprises contacting a mixture of at least part of the final
liquefied product and the fraction of a petroleum oil with a
fluidized catalytic cracking catalyst in a fluidized catalytic
cracking reactor at a temperature of equal to or more than about
400.degree. C.
10. The method of claim 9, wherein the liquefaction step comprises
simultaneously contacting the cellulosic material with the fraction
of a petroleum oil, with a source of hydrogen, and with a
hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C.
11. The method of claim 9, wherein a further organic solvent is
generated in-situ during the liquefaction step.
12. The method of claim 1, wherein the liquefaction step comprises
simultaneously contacting the cellulosic material with a liquid
solvent, with a source of hydrogen, with an acid catalyst and with
a hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C.; and wherein the catalytic cracking step
comprises contacting at least part of the final liquefied product
with a fluidized catalytic cracking catalyst at a temperature of
equal to or more than about 400.degree. C.
13. The method of claim 12, wherein the liquid solvent is water or
a solvent mixture comprising an organic solvent and water.
14. The method of claim 1, wherein the final liquefied product or
part thereof comprises one, two or more compounds chosen from the
group consisting of gamma-valerolactone and/or levulinic acid;
tetrahydrofufuryl and/or tetrahydropyranyl; furfural and/or
hydroxymethylfurfural; mono- and/or di-alcohols and/or mono- and/or
di-ketones; and/or guaiacol and/or syringol components.
15. The method of claim 1, wherein the process further comprises: a
fractionation step comprising fractionating the at least one
cracked product to produce at least one product fraction.
16. The method of claim 15, wherein the process further comprises:
a hydrotreatment step comprising hydrotreating the at least one
product fraction with a source of hydrogen to produce at least one
hydrotreated product fraction.
17. A biofuel component comprising the at least one product
fraction or any product derived from the at least one product
fraction produced in claim 15.
18. A biofuel component comprising the at least one hydrotreated
product fraction or any product derived from the at least one
hydrotreated product fraction produced in claim 16.
19. A process for the production of a biofuel comprising blending
the biofuel component of claim 17 with one or more other components
to produce a biofuel.
20. A process for the production of a biofuel comprising blending
the biofuel component of claim 18 with one or more other components
to produce a biofuel.
Description
[0001] This application claims the benefit of priority of European
Patent Application No. 11189049.7, filed on Nov. 14, 2011, and of
European Patent Application No. 12190054.2, filed on Oct. 25, 2012,
the disclosures of which are incorporated by reference herein in
their entirety.
FIELD OF THE INVENTION
[0002] Embodiments of the invention relate to a process for
conversion of a cellulosic material and use of the products
produced in such a process.
BACKGROUND OF THE INVENTION
[0003] This section is intended to introduce various aspects of the
art, which may be associated with exemplary embodiments of the
present invention. This discussion is believed to assist in
providing a framework to facilitate a better understanding of
particular aspects of the present invention. Accordingly, it should
be understood that this section should be read in this light, and
not necessarily as admissions of any prior art.
[0004] With the diminishing supply of crude mineral oil, use of
renewable energy sources is becoming increasingly important for the
production of liquid fuels. These fuels from renewable energy
sources are often referred to as biofuels.
[0005] Biofuels derived from non-edible renewable energy sources,
such as cellulosic materials, are preferred as these do not compete
with food production. These biofuels are also referred to as second
generation, or advanced, biofuels. Most of these non-edible
cellulosic materials, however, are solid materials that are
cumbersome to convert into biofuels.
[0006] WO2010/135734 describes a method for co-processing a biomass
feedstock and a refinery feedstock in a refinery unit comprising
catalytically cracking the biomass feedstock and the refinery
feedstock in a refinery unit comprising a fluidized reactor,
wherein hydrogen is transferred from the refinery feedstock to
carbon and oxygen of the biomass feedstock. In one of the
embodiments WO2010/135734 the biomass feedstock comprises a
plurality of solid biomass particles having an average size between
50 and 1000 microns. In passing, it is further mentioned that solid
biomass particles can be pre-processed to increase brittleness,
susceptibility to catalytic conversion (e.g. by roasting, toasting,
and/or torrefication) and/or susceptibility to mixing with a
petrochemical feedstock.
[0007] A disadvantage of the process as described in WO2010/135734,
however, is that proper handling of the biomass feedstock
comprising the solid biomass particles is critical to avoid
instability of the feedstock, clogging of feed lines to a fluidized
catalytic cracking unit and/or coking in a fluidized catalytic
cracking unit.
[0008] The article of F. de Miguel Mercader et al, published in the
Journal of Applied Catalysis B: Environmental, 2010, volume 96,
pages 57-66, describes a process for catalytic cracking of an
hydrodeoxygenated pyrolysis oil, derived from forest residue,
together with long residue in a catalytic cracking reactor.
Although the described process gives good results it is indicated
that the hydrodeoxygenation reactions lead to a better product
(with respect to fluidized catalytic cracking (FCC) co-processing)
at the expense of hydrogen. In addition, it is indicated that
during hydrodeoxygenation, reaction conditions are critical to
obtain thermally stable molecules suitable for further processing
in a FCC unit. FIG. 9 of the article further illustrates the
competition between hydro(deoxy)genation and (re)polymerization of
the pyrolysis oil. As explained in the article, fast polymerization
reactions may cause plugging of a reactor.
[0009] It would therefore be an advancement in the art to provide a
less critical process for conversion of a cellulosic material.
SUMMARY
[0010] Such an advancement has been achieved with the process
according to the invention. According to one aspect of the
invention, there is provided a method for conversion of a
cellulosic material. The method comprises a liquefaction step to
produce a final liquefied product, the liquefaction step
comprising: contacting a cellulosic material with a liquid solvent
at a temperature of equal to or more than about 200.degree. C.; or
contacting a cellulosic material with a liquid solvent at a
temperature of equal to or more than about 100.degree. C. in the
presence of a catalyst. The method further comprises a catalytic
cracking step to produce at least one cracked product, the
catalytic cracking step comprising contacting at least part of the
final liquefied product with a fluidized catalytic cracking
catalyst at a temperature of equal to or more than about
400.degree. C.
[0011] In one embodiment, the liquid solvent comprises water and/or
an organic solvent. In another embodiment, the liquefaction step
comprises simultaneously contacting the cellulosic material with an
organic solvent, a source of hydrogen, an acid catalyst and a
hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C. In another embodiment, the liquefaction step
comprises contacting the cellulosic material with an organic
solvent in the presence of an acid catalyst at a temperature of
equal to or more than about 150.degree. C. to produce an
intermediate liquefied product; and subsequently hydrotreating the
intermediate liquefied product with a source of hydrogen in the
presence of a hydrotreatment catalyst to produce a final liquefied
product.
[0012] In one embodiment, the liquid solvent is an organic solvent
and wherein the process further comprises a separation step,
wherein at least a portion of the final liquefied product produced
in the liquefaction step is separated from at least part of the
organic solvent. In another embodiment, the separated portion of
the organic solvent is used in the liquefaction step. In another
embodiment, the catalytic cracking step comprises contacting at
least part of the final liquefied product and a fluid hydrocarbon
co-feed with the fluidized catalytic cracking catalyst at a
temperature of equal to or more than about 400.degree. C.
[0013] In one embodiment, the fluid hydrocarbon co-feed comprises
at least one of a straight run (atmospheric) gas oil, a flashed
distillate, a vacuum gas oil (VGO), a light cycle oil, a heavy
cycle oil, a hydrowax, a coker gas oil, a gasoline, a naphtha, a
diesel, a kerosene, an atmospheric residue ("long residue"), a
vacuum residue ("short residue"), and any combination thereof. In
another embodiment, the liquefaction step comprises contacting a
cellulosic material with an organic solvent at a temperature of
equal to or more than about 100.degree. C. in the presence of a
catalyst, wherein the organic solvent comprises a fraction of a
petroleum oil; and wherein the catalytic cracking step comprises
contacting a mixture of at least part of the final liquefied
product and the fraction of a petroleum oil with a fluidized
catalytic cracking catalyst in a fluidized catalytic cracking
reactor at a temperature of equal to or more than about 400.degree.
C.
[0014] In one embodiment, the liquefaction step comprises
simultaneously contacting the cellulosic material with the fraction
of a petroleum oil, with a source of hydrogen, and with a
hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C. In another embodiment, a further organic
solvent is generated in-situ during the liquefaction step.
[0015] In one embodiment, the liquefaction step comprises
simultaneously contacting the cellulosic material with a liquid
solvent, with a source of hydrogen, with an acid catalyst and with
a hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C.; and wherein the catalytic cracking step
comprises contacting at least part of the final liquefied product
with a fluidized catalytic cracking catalyst at a temperature of
equal to or more than about 400.degree. C. In one embodiment, the
liquid solvent is water or a solvent mixture comprising an organic
solvent and water.
[0016] In one embodiment, the final liquefied product or part
thereof comprises one, two or more compounds chosen from the group
consisting of gamma-valerolactone and/or levulinic acid;
tetrahydrofufuryl and/or tetrahydropyranyl; furfural and/or
hydroxymethylfurfural; mono- and/or di-alcohols and/or mono- and/or
di-ketones; and/or guaiacol and/or syringol components.
[0017] In one embodiment, the process further comprises a
fractionation step comprising fractionating the at least one
cracked product to produce at least one product fraction. In
another embodiment, the process further comprises a hydrotreatment
step comprising hydrotreating the at least one product fraction
with a source of hydrogen to produce at least one hydrotreated
product fraction.
[0018] According to another aspect of the invention, there is
provided a biofuel component comprising material produced from
certain embodiments of the present invention. In one embodiment,
the biofuel component comprises the at least one product fraction
or any product derived from the at least one product fraction
product fraction. In another embodiment, the biofuel component
comprises the at least one hydrotreated product fraction or any
product derived from the at least one hydrotreated product
fraction.
[0019] According to another aspect of the invention, there is
provided a process for the production of a biofuel comprising
blending the biofuel component according to certain aspects of the
invention with one or more other components to produce a
biofuel.
[0020] Without wishing to be bound by any kind of theory it is
believed that due to its composition, the final liquefied product
of certain embodiments of the present invention allows for a more
stable feedstock to a fluidized catalytic cracking process than any
pyrolysis oil and/or any solid biomass particles.
[0021] In addition, it has been found that in certain embodiments
according to the invention coking may be minimized.
[0022] Certain embodiments of the process according to the
invention therefore provide a less critical process for conversion
of a cellulosic material.
[0023] The one or more cracked products of certain embodiments of
the present invention may advantageously be fractionated to produce
one or more product fractions and optionally hydrotreated to
produce one or more hydrotreated product fractions. These one or
more product fractions and/or one or more hydrotreated product
fractions and/or one or more products derived therefrom can
advantageously be used as a biofuel component. Embodiments of the
present invention therefore further provides a process for the
production of a biofuel comprising blending such biofuel components
with one or more other components to produce a biofuel. The
produced biofuel may advantageously be used in a transportation
vehicle.
[0024] Other advantages and features of embodiments of the present
invention will become apparent from the following detailed
description. It should be understood, however, that the detailed
description and the specific examples, while indicating preferred
embodiments of the invention, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the invention will become apparent to those skilled in the
art from this detailed description.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0025] Embodiments of the present invention include a liquefaction
step where a cellulosic material is contacted with a liquid solvent
to produce a final liquefied product. This step may also be
referred to herein as a liquefaction or liquefying of the
cellulosic material. The liquefaction or liquefying may be carried
out by means of a liquefaction or liquefying reaction.
[0026] By liquefaction (also herein referred to as liquefying) is
herein understood to refer at least to the conversion of a solid
material, such as cellulosic material, into one or more liquefied
products.
[0027] By a liquefied product is herein understood to refer at
least to a product that is liquid at a temperature of about
20.degree. C. and a pressure of about 1 bar absolute (0.1
MegaPascal) and/or a product that can be converted into a liquid by
melting (for example by applying heat) or dissolving in a solvent.
Preferably the liquefied product is a liquefied product that is
liquid at a temperature of about 80.degree. C. and a pressure of
about 1 bar absolute (0.1 MegaPascal). The liquefied product may
vary widely in its viscosity and may be more or less viscous.
[0028] Liquefaction of a cellulosic material can comprise cleavage
of covalent linkages in that cellulosic material. For example
liquefaction of lignocellulosic material can comprise cleavage of
covalent linkages in cellulose, hemicellulose and/or lignin present
and/or cleavage of covalent linkages between lignin, hemicelluloses
and/or cellulose.
[0029] As used herein, cellulosic material refers to material
containing cellulose. Preferably the cellulosic material is a
lignocellulosic material. A lignocellulosic material comprises
lignin, cellulose and optionally hemicellulose.
[0030] Advantageously the liquefaction step makes it possible to
liquefy not only the cellulose but also the lignin and
hemicelluloses.
[0031] Any suitable cellulose-containing material may be used as
cellulosic material in the process according to the present
invention. The cellulosic material for use according to the
invention may be obtained from a variety of plants and plant
materials including agricultural wastes, forestry wastes, sugar
processing residues and/or mixtures thereof. Examples of suitable
cellulose-containing materials include agricultural wastes such as
corn stover, soybean stover, corn cobs, rice straw, rice hulls, oat
hulls, corn fibre, cereal straws such as wheat, barley, rye and oat
straw; grasses; forestry products such as wood and wood-related
materials such as sawdust; waste paper; sugar processing residues
such as bagasse and beet pulp; or mixtures thereof.
[0032] The liquefaction step may further comprise drying,
torrefaction, steam explosion, particle size reduction,
densification and/or pelletization of the cellulosic material
before the cellulosic material is contacted with the liquid
solvent. Such drying, torrefaction, steam explosion, particle size
reduction, densification and/or pelletization of the cellulosic
material may advantageously allow for improved process operability
and economics.
[0033] Before being used in the process of the invention, the
cellulosic material is preferably processed into small particles in
order to facilitate liquefaction. Preferably, the cellulosic
material is processed into particles having a particle size
distribution with an average particle size of equal to or more than
about 0.05 millimeter, more preferably equal to or more than about
0.1 millimeter, most preferably equal to or more than about 0.5
millimeter and preferably equal to or less than about 20
centimeters, more preferably equal to or less than about 10
centimeters and most preferably equal to or less than about 3
centimeters. For practical purposes the particle size in the
centimeter and millimeter range can be determined by sieving.
[0034] If the cellulosic material is a lignocellulosic material it
may also have been subjected to a pre-treatment to remove and/or
degrade lignin and/or hemicelluloses. Examples of such
pre-treatments include fractionation, pulping and torrefaction
processes.
[0035] By a liquid solvent is herein preferably understood to refer
at least to a solvent that is liquid at a pressure of about 1 bar
atmosphere (0.1 MegaPascal) and a temperature of about 80.degree.
C. or higher, more preferably about 100.degree. C. or higher. Most
preferably a liquid solvent is herein understood to be a solvent
that is liquid at the temperature and pressure at which the
liquefaction step is carried out.
[0036] In one preferred embodiment the liquid solvent comprises or
is water.
[0037] In another preferred embodiment the liquid solvent comprises
or is an organic solvent. By an organic solvent is herein
understood at least as a solvent comprising one or more hydrocarbon
compounds. By a hydrocarbon compound is herein understood a
compound that contains at least one hydrogen atom and at least one
carbon atom, more preferably a hydrocarbon compound is herein
understood to contain at least one hydrogen atom and at least one
carbon atom bonded to each other via at least one covalent
bond.
[0038] In addition to hydrogen and carbon the hydrocarbon compound
may contain for example heteroatoms such as sulphur, oxygen and/or
nitrogen. Examples of hydrocarbon compounds that may preferably be
present in the organic solvent include acetic acid, formic acid,
levulinic acid and gamma-valerolactone and/or mixtures thereof.
[0039] The organic solvent may comprise polar and/or non-polar
hydrocarbon compounds. In a preferred embodiment the organic
solvent comprises at least one or more polar hydrocarbon compounds.
Preferably the organic solvent comprises more than one, more
preferably more than two, more preferably more than three different
polar hydrocarbon compounds. A measure of the polarity of a polar
hydrocarbon compound is its log P value, where P is defined as the
partition coefficient of a compound in a two phase octanol-water
system. The log P value can be determined experimentally or
calculated according to standard procedures as discussed in
Handbook of Chemistry and Physics, 83.sup.rd Edition, pages 16-43
to 16-47, CRC Press (2002).
[0040] In one embodiment the organic solvent may preferably
comprise one or more polar hydrocarbon compound(s), which one or
more polar hydrocarbon compound(s) preferably is/are a hydrocarbon
compound having a polarity of log P less than +3, more preferably
less than +1. In another embodiment, the polar hydrocarbon compound
is a hydrocarbon compound having a polarity of log P less than
+0.5. In a further embodiment, the polar hydrocarbon compound is a
hydrocarbon compound having a polarity of log P less than 0.
[0041] In another embodiment the organic solvent may preferably
comprise one or more non-polar hydrocarbon compounds(s), which one
or more non-polar hydrocarbon compound(s) preferably is/are a
hydrocarbon compound having a polarity of log P in the range from
+5 to +10, more preferably in the range from +7 to +8.
[0042] In a preferred embodiment the organic solvent comprises one
or more carboxylic acids. By a carboxylic acid is herein understood
a hydrocarbon compound comprising at least one carboxyl (--CO--OH)
group. Such carboxylic acids can be polar hydrocarbon compounds as
herein described above. More preferably the organic solvent
comprises equal to or more than about 5 wt % carboxylic acids, more
preferably equal to or more than about 10 wt % carboxylic acids,
most preferably equal to or more than about 20 wt % of carboxylic
acids, based on the total weight of organic solvent. There is no
upper limit for the carboxylic acid concentration, but for
practical purposes the organic solvent may comprise equal to or
less than about 90 wt %, more preferably equal to or less than
about 80 wt % of carboxylic acids, based on the total weight of
organic solvent. Preferably the organic solvent comprises at least
acetic acid, levulinic acid and/or pentanoic acid. Especially
acetic acid may be useful as it can be simultaneous used as (part
of) the organic solvent as well as used as an acid catalyst.
[0043] In another embodiment the organic solvent comprises
paraffinic compounds, naphthenic compounds, olefinic compounds
and/or aromatic compounds. Such compounds may be present in
refinery streams such as gas oil, fuel oil and/or residue oil.
These refinery streams may therefore also be suitable as organic
solvent in the liquefaction step. This is explained in more detail
below.
[0044] In another preferred embodiment the organic solvent
comprises at least a part of a liquefied product. Preferably part
of the liquefied product (for example part of a final liquefied
product and/or part of an intermediate liquefied product as
described herein below) is therefore recycled to the liquefaction
step to be used as organic solvent. In a preferred embodiment equal
to or more than about 10 wt %, more preferably equal to or more
than about 20 wt % of the organic solvent is obtained from an
intermediate and/or final liquefied product.
[0045] In a preferred embodiment, any recycle of liquefied
product(s) comprises a weight amount of liquefied product(s) of 2
to 100 times the weight of the cellulosic material, more preferably
of 5 to 20 times the weight of the cellulosic material.
[0046] In a preferred embodiment at least part of the organic
solvent is derived from cellulosic, and preferably lignocellulosic,
material. For example in a preferred embodiment at least part of
the organic solvent may be generated in-situ during liquefaction of
the cellulosic material. More preferably, at least part of the
organic solvent is obtained by acid hydrolysis of cellulosic, and
preferably lignocellulosic, material. Examples of possible
hydrocarbon compounds in the organic solvent that may be obtained
by acid hydrolysis of cellulosic, and preferably lignocellulosic,
material include acetic acid, formic acid and levulinic acid.
Hydrocarbon compounds which are obtainable from such acid
hydrolysis products by hydrogenation thereof may also suitably be
used. Examples of such hydrogenated hydrocarbon compounds include
gamma-valerolactone which is obtainable from levulinic acid by
hydrogenation, tetrahydrofufuryl and tetrahydropyranyl components
which are derived from furfural or hydroxymethylfurfural, mono- and
di-alcohols and ketones which are derived from sugars, and guaiacol
and syringol components which are derived from lignin. Preferably
the organic solvent may comprise one, two or more of such
hydrocarbon compounds.
[0047] Further, the above compounds may also become part of the
final liquefied product. Hence, in a preferred embodiment the final
liquefied product or part thereof may comprise one, two or more of
the above listed, optionally hydrogenated, compounds such as
gamma-valerolactone, which can be obtained from levulinic acid by
hydrogenation; tetrahydrofufuryl and tetrahydropyranyl components,
which can be derived from furfural or hydroxymethylfurfural; mono-
and/or di-alcohols and/or mono- and/or di-ketones, which can be
derived from sugars; and/or guaiacol and/or syringol components,
which can be derived from lignin.
[0048] One or more hydrocarbon compounds in the organic solvent may
advantageously be obtainable from the cellulosic material liquefied
in the liquefaction step. The hydrocarbon compound(s) may for
example be generated in-situ and/or recycled and/or used as a
make-up organic solvent, affording significant economic and
processing advantages.
[0049] In one embodiment at least part of the organic solvent in
the liquefaction step is not generated in situ by conversion of the
cellulosic material. Such an ex-situ provided organic solvent may
co-exist with an in-situ formed organic solvent. Such a solvent
that is not generated in-situ but is ex-situ provided may therefore
herein also be referred to as "co-solvent".
[0050] In a preferred embodiment the organic solvent comprises at
least one or more hydrocarbon compound(s) that are at least partly
obtained and/or derived from a source other than the cellulosic
material used as a feedstock in the liquefaction step, for example
a petroleum source (herein also referred to as fossil source).
These one or more hydrocarbon compounds(s) may for example be mixed
with the cellulosic material before starting the liquefaction or
may be added to the reaction mixture during the liquefaction.
[0051] As explained in more detail herein below, in one embodiment
the organic solvent in the liquefaction step comprises one or more
hydrocarbon compounds that also may be suitable to act as a fluid
hydrocarbon co-feed in the catalytic cracking step. In a further
embodiment the organic solvent used in the liquefaction step
contains one or more hydrocarbon compounds obtained from a
conventional crude oil (also sometimes referred to as a petroleum
oil or mineral oil); an unconventional crude oil (that is, oil
produced or extracted using techniques other than the traditional
oil well method); a renewable source (such as for example a
vegetable oil); or a Fisher Tropsch oil and/or a mixture thereof.
More preferably the organic solvent used in the liquefaction step
comprises or consists of a fraction of a petroleum oil or renewable
oil. Preferably the organic solvent comprises or consists of a
straight run (atmospheric) gas oils, flashed distillate, vacuum gas
oils (VGO), light cycle oil, heavy cycle oil, hydrowax, coker gas
oils, diesel, gasoline, kerosene, naphtha, liquefied petroleum
gases, atmospheric residue ("long residue") and vacuum residue
("short residue") and/or mixtures thereof. Most preferably the
organic solvent comprises or consists of a long residue.
[0052] Hence, preferably the co-solvent as mentioned above, is an
organic solvent that comprises or consists of a petroleum oil or a
fraction thereof. The advantage of using a petroleum oil or a
fraction thereof as an organic solvent or organic co-solvent is
that this organic solvent or co-solvent may also be a suitable feed
to the catalytic cracking step. When the organic solvent or organic
co-solvent comprises or is a petroleum oil or a fraction thereof,
this may lead to a more efficient and cheaper operation and
hardware as no separation of such a organic solvent or organic
co-solvent may be needed.
[0053] In a preferred embodiment, the present invention therefore
also provides a process for conversion of a cellulosic material
comprising
a) a liquefaction step, comprising contacting a cellulosic material
with an organic solvent at a temperature of equal to or more than
about 100.degree. C. in the presence of a catalyst, wherein the
organic solvent comprises a fraction of a petroleum oil, to produce
a final liquefied product; b) a catalytic cracking step, comprising
contacting a mixture of at least part of the final liquefied
product and the fraction of a petroleum oil with a fluidized
catalytic cracking catalyst in a fluidized catalytic cracking
reactor at a temperature of equal to or more than about 400.degree.
C., to produce one or more cracked products. One skilled in the art
will understand that the liquefied product in step b) may suitably
be the final liquefied product or any part thereof.
[0054] The fraction of a petroleum oil is preferably chosen from
the group consisting of straight run (atmospheric) gas oils,
flashed distillate, vacuum gas oils (VGO), light cycle oil, heavy
cycle oil, hydrowax, coker gas oils, diesel, gasoline, kerosene,
naphtha, liquefied petroleum gases, atmospheric residue ("long
residue") and vacuum residue ("short residue") and/or mixtures
thereof as indicated above. At least part of this fraction of a
petroleum oil or the whole of this fraction of a petroleum oil may
be contacted with the fluidized catalytic cracking catalyst in step
b).
[0055] In a preferred embodiment the liquefaction step comprises
contacting the cellulosic material simultaneously with the fraction
of a petroleum oil, with a source of hydrogen, with a hydrogenation
catalyst, and optionally with an acid catalyst, at a temperature of
equal to or more than about 150.degree. C. to produce a final
liquefied product.
[0056] Other preferences are as described elsewhere herein.
[0057] In one embodiment, the organic solvent is partly derived
from cellulosic, preferably lignocellulosic, material and partly
derived from a petroleum source. In a preferred embodiment the
organic solvent comprises a mixture of i) a fraction of a petroleum
oil and ii) one or more hydrocarbon compounds that may be obtained
by acid hydrolysis of cellulosic, preferably lignocellulosic,
material.
[0058] In a preferred embodiment the organic solvent comprises at
least one or more carboxylic acids, such as for example acidic
acid, levulinic acid and/or pentanoic acid, which carboxylic
acid(s) are preferably present before beginning the liquefaction
reaction, that is, which carboxylic acid(s) are preferably not
in-situ obtained and/or derived from the cellulosic material during
the reaction.
[0059] Advantageously, the organic solvent may be water-miscible at
the reaction temperature of the liquefaction step. In a preferred
embodiment, the liquefaction step comprises contacting the
cellulosic material with a solvent mixture comprising the organic
solvent and water. Hence, in a preferred embodiment the liquid
solvent may comprise a solvent mixture containing water and an
organic solvent.
[0060] The water in the solvent mixture may for example be
generated in-situ during the liquefaction step. The organic solvent
is preferably present in an amount of less than or equal to about
95% by weight, more preferably less than or equal to about 90% by
weight and most preferably less than or equal to about 80% by
weight, based on the total weight of water and organic solvent.
Further the organic solvent is preferably present in an amount of
more than or equal to about 5% by weight, more preferably more than
or equal to about 10% by weight, and most preferably more than or
equal to about 20% by weight, based on the total weight of water
and organic solvent. The organic solvent is preferably present in
an amount of from about 20% to about 60% by weight, based on the
total weight of the water and organic solvent.
[0061] Preferably water is present in an amount of less than or
equal to about 95% by weight, more preferably an amount of less
than or equal to about 90% by weight, and most preferably less than
or equal to about 80% by weight, based on the total weight of water
and organic solvent. Further water is preferably present in an
amount of more than or equal to about 5% by weight, more preferably
in an amount of more than or equal to about 10% by weight, most
preferably about 20% by weight, based on the total weight of water
and organic solvent. Preferably, water is present in an amount of
from about 40% to about 80% by weight based on the total weight of
the water and organic solvent. Preferably a solvent mixture
contains the organic solvent and water in a weight ratio of organic
solvent to water of less than or equal to 9:1, more preferably less
than or equal to 8:2. Further a solvent mixture preferably contains
the organic solvent and water in a weight ratio of organic solvent
to water of more than or equal to 1:9 more preferably more than or
equal to 2:8.
[0062] The cellulosic material and the organic solvent or--if a
solvent mixture containing water and organic solvent is
present--the solvent mixture are preferably mixed in a solvent
mixture or organic solvent-to-cellulosic material ratio of 2:1 to
20:1 by weight, more preferably in a solvent mixture or organic
solvent-to-cellulosic material ratio of 3:1 to 15:1 by weight and
most preferably in a solvent mixture or organic
solvent-to-cellulosic material ratio of 4:1 to 10:1 by weight.
[0063] The liquefaction step may be carried out in the presence or
absence of a catalyst. The use of a catalyst advantageously allows
one to lower the reaction temperature.
[0064] Hence, in one embodiment the liquefaction step may comprise
contacting a cellulosic material with an organic solvent,
optionally in the essential absence of an externally provided acid
catalyst, at a temperature of equal to or more than about
200.degree. C., more preferably equal to or more than about
250.degree. C., still more preferably a temperature of equal to or
more than about 300.degree. C. and preferably a temperature equal
to or less than about 450.degree. C.
[0065] In another embodiment the liquefaction step may comprise
contacting a cellulosic material with an organic solvent in the
presence of a, preferably acid, catalyst at a temperature of equal
to or more than about 100.degree. C., more preferably a temperature
of equal to or more than about 150.degree. C., still more
preferably a temperature of equal to or more than about 200.degree.
C. and preferably a temperature of equal to or less than about
450.degree. C., more preferably a temperature of equal to or less
than about 350.degree. C.
[0066] Preferably the catalyst is an acid catalyst. The acid
catalyst for use in liquefaction step to the invention may be any
acid catalyst known in the art to be suitable for liquefying of
cellulosic material. For example, the acid catalyst may be a
Bronsted acid or a Lewis acid. Further the acid catalyst may be a
homogeneous catalyst or a heterogeneous catalyst. Preferably the
acid catalyst is a homogeneous or finely dispersed heterogeneous
catalyst, most preferably the acid catalyst is a homogeneous
catalyst. Preferably the acid catalyst remains liquid and stable
under the liquefaction conditions and preferably it is sufficiently
strong to effect cleavage of the covalent linkages and dehydration
of the cellulosic material.
[0067] Preferably the acid catalyst is a Bronsted acid and more
preferably the acid catalyst is a mineral or organic acid,
preferably a mineral or organic acid having a pKa value below 5.0,
more preferably below 4.25, still more preferably below 3.75, even
more preferably below 3.0, and most preferably below 2.5.
[0068] Examples of suitable mineral acids include sulphuric acid,
para toluene sulphonic acid, nitric acid, hydrochloric acid and
phosphoric acid, and mixtures thereof. In a preferred embodiment,
the acid catalyst used in the liquefaction step is sulphuric acid
or phosphoric acid.
[0069] Examples of suitable organic acids which may be used in the
liquefaction step include levulinic acid, acetic acid, oxalic acid,
formic acid, lactic acid, citric acid, trichloracetic acid and
mixtures thereof. If the acid catalyst is an organic acid, it may
suitably be an organic acid that is generated in-situ or ex-situ
(i.e. provided externally). By an in-situ generated organic acid is
herein understood at least to include an organic catalyst that is
generated in-situ during liquefaction of the cellulosic material.
An example of such an in-situ generated organic acid may be acetic
acid or formic acid.
[0070] The acid catalyst is preferably present in an amount of less
than or equal to about 35% by weight, more preferably less than or
equal to about 20% by weight, even more preferably less than or
equal to about 10% by weight and still more preferably less than or
equal to about 5% by weight, and most preferably less than or equal
to about 1% by weight, based on the total weight of organic solvent
or--if applicable--solvent mixture and acid catalyst. Further the
acid catalyst is preferably present in an amount of more than or
equal to about 0.01% by weight, more preferably more than or equal
to about 0.1% by weight and most preferably more than or equal to
about 0.2% by weight, based on the total weight of organic solvent
or--if applicable--solvent mixture and acid catalyst. It will be
appreciated that for any given acid catalyst the amount of acid
required will depend on the strength of the acid. In one preferred
embodiment, the acid catalyst is present in an amount of from about
1% to about 10% by weight, preferably from about 2% to about 5% by
weight, based on the weight of organic solvent or--if
applicable--solvent mixture and acid catalyst.
[0071] In a preferred embodiment at least part of the liquefied
product obtained after liquefaction of the cellulosic material is
hydrogenated. Liquefaction and hydrogenation may be carried out
simultaneously or hydrogenation may be carried out subsequent to
the liquefaction.
[0072] In one embodiment the liquefaction step comprises contacting
the cellulosic material with the organic solvent in the presence of
an acid catalyst at a temperature of equal to or more than about
150.degree. C. to produce an intermediate liquefied product; and
subsequently hydrotreating the intermediate liquefied product with
a source of hydrogen in the presence of a hydrotreatment catalyst
to produce a final liquefied product. Preferably hydrotreating of
the intermediate liquefied product comprises hydrogenating of the
intermediate liquefied product and preferably the hydrotreatment
catalyst is a hydrogenation catalyst.
[0073] In another embodiment the liquefaction step comprises
contacting the cellulosic material simultaneously with the organic
solvent, a source of hydrogen, the acid catalyst and a
hydrogenation catalyst at a temperature of equal to or more than
about 150.degree. C. to produce a final liquefied product. In this
case the liquefaction step can advantageously comprise the
simultaneous hydrolysis and hydrogenation of the cellulosic
material, resulting in an improved degree of liquefaction. By
simultaneous contact is understood contact of the cellulosic
material with one of the specified features in the presence of the
remaining features. In this way simultaneous hydrolysis and
hydrogenation of the cellulosic material can be effected as any
hydrolysis product can be in-situ hydrogenated.
[0074] The hydrogenation catalyst is preferably a hydrogenation
catalyst that is resistant to the combination of the organic
solvent (or if applicable the solvent mixture) and, if present, the
acid catalyst.
[0075] For example the hydrogenation catalyst can comprise a
heterogeneous and/or homogeneous catalyst. In a preferred
embodiment the hydrogenation catalyst is a homogeneous catalyst. In
another preferred embodiment the hydrogenation catalyst is a
heterogeneous catalyst. The hydrogenation catalyst preferably
comprises a hydrogenation metal known to be suitable for
hydrogenation reactions, such as for example iron, molybdenum,
cobalt, nickel, copper, ruthenium, rhodium, palladium, iridium,
platinum and gold, or mixtures thereof. The hydrogenation catalyst
comprising such a hydrogenation metal may be sulfided.
[0076] In a further embodiment sulfided hydrogenation catalysts may
be used such as for example a catalyst based on Molybdenum sulfide,
potentially including Cobalt and/or Nickel as a promotor.
[0077] If the hydrogenation catalyst is a heterogeneous catalyst,
the catalyst preferably comprises a hydrogenation metal supported
on a carrier. Suitable carriers include for example carbon,
alumina, titanium dioxide, zirconium dioxide, silicon dioxide and
mixtures thereof. Examples of preferred heterogeneous hydrogenation
catalysts include ruthenium, platinum or palladium supported on a
carbon carrier. Other preferred examples of heterogeneous
hydrogenation catalysts include ruthenium supported on titanium
dioxide (TiO2), platina supported on titanium dioxide and ruthenium
supported on zirconium dioxide(ZrO2). The heterogeneous catalyst
and/or carrier may have any suitable form including the form of a
mesoporous powder, granules or extrudates or a megaporous structure
such as a foam, honeycomb, mesh or cloth. The heterogeneous
catalyst may be present in a liquefaction reactor comprised in a
fixed bed or ebullated slurry. Preferably the heterogeneous
catalyst is present in a liquefaction reactor as a fixed bed.
[0078] If the hydrogenation catalyst is a homogeneous hydrogenation
catalyst, the catalyst preferably comprises an organic or inorganic
salt of the hydrogenation metal, such as for example the acetate-,
acetylacetonate-, nitrate-, sulphate- or chloride-salt of
ruthenium, platinum or palladium. Preferably the homogeneous
catalyst is an organic or inorganic acid salt of the hydrogenation
metal, wherein the acid is an acid which is already present in the
process as acid catalyst or product.
[0079] The source of hydrogen may be any source of hydrogen known
to be suitable for hydrogenation purposes. It may for example
include hydrogen gas, but also an hydrogen-donor such as for
example formic acid. Preferably the source of hydrogen is a
hydrogen gas. Such a hydrogen gas can be applied in the process of
the invention at a partial hydrogen pressure that preferably lies
in the range from about 2 to 200 bar absolute (0.1 to 20
MegaPascal), more preferably in the range from about 10 to 170 bar
absolute (1 to 17 MegaPascal), and most preferably in the range
from 30 to about 150 bar absolute (3 to 15 MegaPascal). A hydrogen
gas can be supplied to a liquefaction reactor co-currently,
cross-currently or counter-currently to the cellulosic material.
Preferably a hydrogen gas is supplied counter-currently to the
cellulosic material.
[0080] The liquefaction step can be carried out at any total
pressure known to be suitable for liquefaction processes. The
process can be carried out under a total pressure that preferably
lies in the range from about 2 to 200 bar absolute (0.1 to 20
MegaPascal), more preferably in the range from about 10 to 170 bar
absolute (1 to 17 MegaPascal), and most preferably in the range
from about 30 to 150 bar absolute (3 to 15 MegaPascal).
[0081] The liquefaction process according to the invention can be
carried out batch-wise, semi-batch wise and continuously.
[0082] During the liquefaction step, the cellulosic material is
liquefied, i.e. the cellulosic material is converted into one or
more liquefied products, to produce a final liquefied product.
[0083] By a final liquefied product is herein preferably understood
to refer at least to a liquefied product which is ready to be
forwarded to the catalytic cracking step. The final liquefied
product may have been hydrogenated (as explained herein above) or
not. Further the final liquefied product may have been separated
from the reaction effluent or not. Preferably the final liquefied
product has been hydrogenated and/or is obtained after one or more
separations as described herein below.
[0084] The reaction effluent produced in the liquefaction step may
include so-called humins, the liquefied product(s) and for example
water, co-solvent, acid catalyst, and/or hydrogenation catalyst
and/or gaseous products such as for example hydrogen. In a
preferred embodiment the liquefaction step may further comprise
separating a final liquefied product from a reaction effluent
produced in the liquefaction step.
[0085] By humins is understood the solid insoluble material
remaining after liquefaction. It is sometimes also referred to as
char.
[0086] The liquefied product(s) may comprise monomeric and/or
oligomeric compounds and optionally excess water produced during
the liquefaction process. From the liquefied product a product
containing monomeric and oligomeric compounds may be separated.
Also part of the liquefied product may be separated for recycling
to the liquefaction step as organic solvent.
[0087] The reaction effluent is preferably forwarded to a
separation section. In the separation section insoluble humins,
monomeric and/or oligomeric compounds and/or water, co-solvent
and/or acid catalyst can be separated off from the reaction
effluent.
[0088] In one embodiment the humins may be separated from the
reaction effluent in a manner known to be suitable for this
purpose. Preferably such humins are separated off via filtration or
settling. Any humins formed in the liquefaction step can be
converted to diesel, kerosene and gasoline fraction in the
catalytic cracking step of the process according to the invention
or in another conventional refinery step.
[0089] In another embodiment the liquefied products and/or any
co-solvent are separated from the reaction effluent in a manner
known to be suitable for this purpose. Preferably liquefied
products and/or any co-solvent are separated off by liquid/liquid
separation techniques, such as phase separation, (solvent)
extraction and/or membrane filtration or (vacuum) distillation.
[0090] If desired the monomeric products and oligomeric products
may be conveniently separated from each other using one or more
membranes. For example, monomeric compounds and/or optionally water
can be separated from any C9-C20 oligomeric compounds and C20+
oligomeric compounds by a ceramic membrane (for example a TiO.sub.2
membrane) or a polymeric membrane (for example a Koch MPF 34
(flatsheet) or a Koch MPS-34 (spiral wound) membrane). The C9-C20
oligomers and the C20+ oligomers can conveniently be separated from
each other with for example a polymer grafted ZrO.sub.2 membrane.
The use of membranes for these separations can advantageously
improve the energy efficiency of the process.
[0091] In another embodiment excess water produced during the
liquefaction step is removed by distillation, pervaporation and/or
reversed osmosis.
[0092] In a preferred embodiment, at least part of any water,
co-solvent, acid catalyst and/or hydrogenation catalyst is
advantageously recovered to be recycled for re-use in the
liquefaction step. In a further preferred embodiment, this recycle
stream also contains at least part of any monomeric compounds
and/or oligomeric products. Any excess of water, co-solvent, acid
catalyst, hydrogenation catalysts and/or monomeric compounds is
preferably purged via a purge stream. In the liquefaction step,
preferably more than or equal to about 50% by weight, more
preferably more than or equal to about 60% by weight and most
preferably more than or equal to about 70% by weight of the
cellulosic material may advantageously be liquefied into liquefied
product, preferably in less than about 3 hours.
[0093] When the co-solvent is an organic co-solvent such as a
petroleum oil or a fraction of a petroleum oil, it may be
advantageous not to recycle the co-solvent but to co-feed the
co-solvent with the final liquefied product into the catalytic
cracking step. If the liquefaction step comprises hydrogenating of
the one or more liquefied products, the petroleum oil or a fraction
of the petroleum oil may suitably also be hydrogenated. This may be
advantageous during the catalytic cracking step.
[0094] The catalytic cracking step comprises contacting at least
part of the final liquefied product with a fluidized catalytic
cracking catalyst at a temperature of equal to or more than about
400.degree. C., to produce one or more cracked products.
[0095] In one embodiment the final liquefied product or part
thereof may comprises one, two or more compounds chosen from the
group consisting of gamma-valerolactone and/or levulinic acid;
tetrahydrofufuryl and/or tetrahydropyranyl; furfural and/or
hydroxymethylfurfural; mono- and/or di-alcohols and/or mono- and/or
di-ketones; and/or guaiacol and/or syringol components.
[0096] In a further embodiment the final liquefied product or part
thereof is a fraction of the reaction effluent obtained from the
liquefaction step which comprises or essentially consists of one or
more, preferably monomeric, compounds containing equal to or less
than 9 carbon atoms, preferably equal to or less than 6 carbon
atoms and most preferably equal to or less than 5 carbon atoms.
More preferably the final liquefied product in this embodiment
comprises one or more compounds containing equal to or less than 9
carbon atoms, preferably equal to or less than 6 carbon atoms and
most preferably equal to or less than 5 carbon atoms and/or having
a molecular weight of equal to or less than about 200 Dalton and/or
having an atmospheric boiling point of equal to or less than about
200.degree. C. as determined at about 0.1 MegaPascal.
[0097] Preferably such a final liquefied product includes
hydrocarbon compounds and/or oxygenates, such as for example
alcohols. For example such a final liquefied product may comprise
or may consist of mono- and/or di-alcohols and/or mono- and/or
di-ketones which are derived from sugars. More preferably such
final liquefied product is a final liquefied product containing
butanone, butanol and/or furfural.
[0098] In another embodiment the final liquefied product or part
thereof is a fraction of the reaction effluent obtained from the
liquefaction step which comprises or essentially consists of one or
more, preferably monomeric, compounds containing equal to or more
than 9 carbon atoms, preferably equal to or more than 10 carbon
atoms, and most preferably equal to or more than 11 carbon atoms.
More preferably the final liquefied product in this embodiment
comprises one or more compounds containing equal to or more than 9
carbon atoms, preferably equal to or more than 10 carbon atoms and
most preferably equal to or more than 11 carbon atoms, and/or
having a molecular weight of equal to or more than about 200 Dalton
and/or an atmospheric boiling point of equal to or more than about
200.degree. C. as determined at about 0.1 MegaPascal.
[0099] The final liquefied product or part thereof can be produced
as described above. The final liquefied product or any part thereof
to be contacted with the fluidized catalytic cracking catalyst can
optionally be obtained after a separation step as described above.
The final liquefied product or any part thereof can be fed to a
fluidized catalytic cracking reactor in an essentially liquid
state, in an essentially gaseous state or in a partially
liquid-partially gaseous state. When entering the fluidized
catalytic cracking reactor in an essentially or partially liquid
state, the final liquefied product or any part thereof preferably
vaporizes upon entry and preferably is contacted in the gaseous
state with the fluidized catalytic cracking catalyst.
[0100] In a preferred embodiment the catalytic cracking step
comprises contacting at least part of the final liquefied product
and a fluid hydrocarbon co-feed with the fluidized catalytic
cracking catalyst, preferably in a fluidized catalytic cracking
reactor, at a temperature of equal to or more than about
400.degree. C., to produce the one or more cracked products. That
is, in a preferred embodiment also a fluid hydrocarbon co-feed
other than the at least part of the final liquefied product may be
added into a fluidized catalytic cracking reactor.
[0101] By a hydrocarbon co-feed is herein understood to refer at
least to a co-feed that contains one or more hydrocarbon compounds.
By a fluid hydrocarbon co-feed is herein understood a hydrocarbon
feed that is not in a solid state. The fluid hydrocarbon co-feed is
preferably a liquid hydrocarbon co-feed, a gaseous hydrocarbon
co-feed, or a mixture thereof. The fluid hydrocarbon co-feed can be
fed to a catalytic cracking reactor in an essentially liquid state,
in an essentially gaseous state or in a partially liquid-partially
gaseous state. When entering the catalytic cracking reactor in an
essentially or partially liquid state, the fluid hydrocarbon
co-feed preferably vaporizes upon entry and preferably is contacted
in the gaseous state with the fluidized catalytic cracking
catalyst.
[0102] The fluid hydrocarbon co-feed can be any non-solid
hydrocarbon co-feed known to the skilled person to be suitable as a
co-feed for a catalytic cracking unit. The fluid hydrocarbon
co-feed can for example be obtained from a conventional crude oil
(also sometimes referred to as a petroleum oil or mineral oil), an
unconventional crude oil (that is, oil produced or extracted using
techniques other than the traditional oil well method) or a Fisher
Tropsch oil and/or a mixture thereof.
[0103] The fluid hydrocarbon co-feed may even be a fluid
hydrocarbon co-feed from a renewable source, such as for example a
vegetable oil.
[0104] In one embodiment the fluid hydrocarbon co-feed is derived
from a, preferably conventional, crude oil. Examples of
conventional crude oils include West Texas Intermediate crude oil,
Brent crude oil, Dubai-Oman crude oil, Arabian Light crude oil,
Midway Sunset crude oil or Tapis crude oil.
[0105] More preferably the fluid hydrocarbon co-feed comprises a
fraction of a, preferably conventional, crude oil or renewable oil.
Preferred fluid hydrocarbon co-feeds include straight run
(atmospheric) gas oils, flashed distillate, vacuum gas oils (VGO),
light cycle oil, heavy cycle oil, hydrowax, coker gas oils, diesel,
gasoline, kerosene, naphtha, liquefied petroleum gases, atmospheric
residue ("long residue") and vacuum residue ("short residue")
and/or mixtures thereof. Most preferably the fluid hydrocarbon
co-feed comprises a long residue.
[0106] The composition of the fluid hydrocarbon co-feed may vary
widely. The fluid hydrocarbon co-feed may for example contain
paraffins, olefins and aromatics.
[0107] Preferably the fluid hydrocarbon co-feed comprises equal to
or more than 1 wt % paraffins, more preferably equal to or more
than about 5 wt % paraffins, and most preferably equal to or more
than about 10 wt % paraffins, and preferably equal to or less than
about 100 wt % paraffins, more preferably equal to or less than
about 90 wt % paraffins, and most preferably equal to or less than
about 30 wt % paraffins, based on the total fluid hydrocarbon
co-feed. By paraffins both normal-, cyclo- and branched-paraffins
are understood.
[0108] In a preferred embodiment the fluid hydrocarbon co-feed
comprises or consists of a paraffinic fluid hydrocarbon co-feed. By
a paraffinic fluid hydrocarbon co-feed is herein understood to
refer at least to a fluid hydrocarbon co-feed comprising at least
about 50 wt % of paraffins, preferably at least about 70 wt % of
paraffins, based on the total weight of the fluid hydrocarbon
co-feed. For practical purposes the paraffin content of all fluid
hydrocarbon co-feeds having an initial boiling point of at least
about 260.degree. C. can be measured by means of ASTM method
D2007-03 titled "Standard test method for characteristic groups in
rubber extender and processing oils and other petroleum-derived
oils by clay-gel absorption chromatographic method", wherein the
amount of saturates will be representative for the paraffin
content. For all other fluid hydrocarbon co-feeds the paraffin
content of the fluid hydrocarbon co-feed can be measured by means
of comprehensive multi-dimensional gas chromatography (GCxGC), as
described in P. J. Schoenmakers, J. L. M. M. Oomen, J. Blomberg, W.
Genuit, G. van Velzen, J. Chromatogr. A, 892 (2000) p. 29 and
further.
[0109] Examples of paraffinic fluid hydrocarbon co-feeds include
so-called Fischer-Tropsch derived hydrocarbon streams such as
described in WO2007/090884 and herein incorporated by reference, or
a hydrogen rich feed like hydrotreater product or hydrowax. By
Hydrowax is understood the bottoms fraction of a hydrocracker.
Examples of hydrocracking processes which may yield a bottoms
fraction that can be used as fluid hydrocarbon co-feed, are
described in EP-A-699225, EP-A-649896, WO-A-97/18278, EP-A-705321,
EP-A-994173 and U.S. Pat. No. 4,851,109 and herein incorporated by
reference.
[0110] In a preferred embodiment the fluid hydrocarbon co-feed
comprises equal to or more than about 8 wt % elemental hydrogen,
more preferably more than about 12 wt % elemental hydrogen (i.e.
hydrogen atoms), based on the total fluid hydrocarbon co-feed on a
dry basis (i.e. water-free basis). A high content of elemental
hydrogen, such as a content of equal to or more than about 8 wt %,
allows the hydrocarbon feed to act as a cheap hydrogen donor in the
catalytic cracking process. A particularly preferred fluid
hydrocarbon co-feed having an elemental hydrogen content of equal
to or more than about 8 wt % is Fischer-Tropsch derived waxy
raffinate. Such Fischer-Tropsch derived waxy raffinate may for
example comprise about 85 wt % of elemental carbon and about 15 wt
% of elemental hydrogen.
[0111] When a fluid hydrocarbon co-feed is present, the weight
ratio of fluid hydrocarbon co-feed to liquefied product(s) (or part
thereof) is preferably equal to or more than 50 to 50 (5:5), more
preferably equal to or more than 70 to 30 (7:3), still more
preferably equal to or more than 80 to 20 (8:2), even still more
preferably equal to or more than 90 to 10 (9:1). For practical
purposes the weight ratio of fluid hydrocarbon co-feed to liquefied
product(s) (or part thereof) is preferably equal to or less than
99.9 to 0.1 (99.9:0.1), more preferably equal to or less than 95 to
5 (95:5). The fluid hydrocarbon co-feed and the final liquefied
product (or part thereof) are preferably being fed to a fluidized
catalytic cracking reactor in a weight ratio within the above
ranges.
[0112] The amount of liquefied product(s), based on the total
weight of liquefied product(s) and fluid hydrocarbon co-feed
supplied to a fluidized catalytic cracking reactor, is preferably
equal to or less than about 50 wt %, more preferably equal to or
less than about 30 wt %, most preferably equal to or less than
about 20 wt % and even more preferably equal to or less than about
10 wt %. For practical purposes the amount of liquefied product(s)
present, based on the total weight of liquefied product(s) and
fluid hydrocarbon co-feed supplied to a fluidized catalytic
cracking reactor, is preferably equal to or more than about 0.1 wt
%, more preferably equal to or more than about 1 wt %.
[0113] The catalytic cracking step is preferably carried out in a
fluidized catalytic cracking reactor. The fluidized catalytic
cracking reactor can be any fluidized catalytic cracking reactor
known in the art to be suitable for the purpose, including for
example a fluidized dense bed reactor or a riser reactor. Most
preferably the catalytic cracking step is carried out in a riser
reactor. Preferably this fluidized catalytic cracking reactor is
part of a fluidized catalytic cracking (FCC) unit.
[0114] In one embodiment, where the organic solvent in the
liquefaction step comprises one or more hydrocarbon compounds that
also may suitable act as a fluid hydrocarbon co-feed, preferably a
mixture of the liquefied product(s) and any organic solvent may be
supplied to the fluidized catalytic cracking reactor. For example
when a petroleum oil or a fraction thereof is used as a co-solvent
in the liquefaction step, the fluid hydrocarbon co-feed as
described herein may comprise or consist of such a co-solvent. In a
further embodiment the organic solvent used in the liquefaction
step is chosen from the fluid hydrocarbon co-feeds described above.
Preferences for the fluid hydrocarbon co-feed are as described
herein above.
[0115] In another preferred embodiment, the fluidized catalytic
cracking reactor is a riser reactor and the fluid hydrocarbon
co-feed is supplied to a riser reactor at a location downstream of
the location where the liquefied product(s) is/are supplied to a
riser reactor.
[0116] In a still further embodiment, a mixture of the liquefied
product(s) and a first hydrocarbon co-feed (which may for example
be the organic solvent when the organic solvent is chosen from the
described fluid hydrocarbon co-feeds) is supplied to a riser
reactor at a first location and a second fluid hydrocarbon co-feed
is supplied to the riser reactor at a second location downstream of
the first location. Preferences for the first and second fluid
hydrocarbon co-feed are as described herein above.
[0117] By a riser reactor is herein understood an elongated
essentially tube-shaped reactor suitable for carrying out catalytic
cracking reactions. The elongated essentially tube-shaped reactor
is preferably oriented in an essentially vertical manner.
[0118] Examples of suitable riser reactors are described in the
Handbook titled "Fluid Catalytic Cracking technology and
operations", by Joseph W. Wilson, published by PennWell Publishing
Company (1997), chapter 3, especially pages 101 to 112, herein
incorporated by reference.
[0119] The riser reactor may be a so-called internal riser reactor
or a so-called external riser reactor as described therein.
[0120] Most preferably the internal riser reactor is an essentially
vertical essentially tube-shaped reactor, that may have an
essentially vertical upstream end located outside a vessel and an
essentially vertical downstream end located inside the vessel. The
vessel is suitably a reaction vessel suitable for catalytic
cracking reactions and/or a vessel that comprises one or more
cyclone separators and/or swirl tubes. The internal riser reactor
may be especially advantageous in the catalytic cracking step as it
may be less prone to plugging, thereby increasing safety and
hardware integrity.
[0121] The length of the riser reactor may vary widely. For
practical purposes the riser reactor preferably has a length in the
range from equal to or more than 10 meters, more preferably equal
to or more than 15 meters and most preferably equal to or more than
20 meters, to equal to or less than 65 meters, more preferably
equal to or less than 55 meters and most preferably equal to or
less than 45 meters.
[0122] In a preferred embodiment the liquefied product(s) produced
in the liquefaction step are supplied to a riser reactor, at the
bottom of this riser reactor. This may advantageously result in
in-situ water formation at the bottom of the reactor. The in-situ
water formation may lower the hydrocarbon partial pressure and
reduce second order hydrogen transfer reactions, thereby resulting
in higher olefin yields. Preferably the hydrocarbon partial
pressure is lowered to a pressure in the range from about 0.7 to
2.8 bar absolute (0.07 to 0.28 MegaPascal), more preferably about
1.2 to 2.8 bar absolute (0.12 to 0.28 MegaPascal).
[0123] It may be advantageous to also add a lift gas at the bottom
of the riser reactor. Examples of such a liftgas include steam,
vaporized oil and/or oil fractions, and mixtures thereof. Steam is
most preferred as a lift gas from a practical perspective. However,
the use of a vaporized oil and/or oil fraction (preferably
vaporized liquefied petroleum gas, gasoline, diesel, kerosene or
naphtha) as a liftgas may have the advantage that the liftgas can
simultaneously act as a hydrogen donor and may prevent or reduce
coke formation. Further if a fluid hydrocarbon co-feed is used as
an organic solvent in the liquefaction step, also vaporized organic
solvent may be used as a liftgas.
[0124] The fluidized catalytic cracking catalyst can be any
catalyst known to the skilled person to be suitable for use in a
cracking process. Preferably, the fluidized catalytic cracking
catalyst comprises a zeolitic component. In addition, the fluidized
catalytic cracking catalyst can contain an amorphous binder
compound and/or a filler. Examples of the amorphous binder
component include silica, alumina, titania, zirconia and magnesium
oxide, or combinations of two or more of them. Examples of fillers
include clays (such as kaolin).
[0125] The zeolite is preferably a large pore zeolite. The large
pore zeolite includes a zeolite comprising a porous, crystalline
aluminosilicate structure having a porous internal cell structure
on which the major axis of the pores is in the range of about 0.62
nanometer to about 0.8 nanometer. The axes of zeolites are depicted
in the `Atlas of Zeolite Structure Types`, of W. M. Meier, D. H.
Olson, and Ch. Baerlocher, Fourth Revised Edition 1996, Elsevier,
ISBN 0-444-10015-6. Examples of such large pore zeolites include
FAU or faujasite, preferably synthetic faujasite, for example,
zeolite Y or X, ultra-stable zeolite Y (USY), Rare Earth zeolite
Y(=REY) and Rare Earth USY (REUSY). According to the present
invention USY is preferably used as the large pore zeolite.
[0126] The fluidized catalytic cracking catalyst can also comprise
a medium pore zeolite. The medium pore zeolite that can be used
according to the present invention is a zeolite comprising a
porous, crystalline aluminosilicate structure having a porous
internal cell structure on which the major axis of the pores is in
the range of about 0.45 nanometer to about 0.62 nanometer. Examples
of such medium pore zeolites are of the MFI structural type, for
example, ZSM-5; the MTW type, for example, ZSM-12; the TON
structural type, for example, theta one; and the FER structural
type, for example, ferrierite. According to the present invention,
ZSM-5 is preferably used as the medium pore zeolite.
[0127] According to another embodiment, a blend of large pore and
medium pore zeolites may be used. The ratio of the large pore
zeolite to the medium pore size zeolite in the cracking catalyst is
preferably in the range of 99:1 to 70:30, more preferably in the
range of 98:2 to 85:15.
[0128] The total amount of the large pore size zeolite and/or
medium pore zeolite that is present in the cracking catalyst is
preferably in the range of about 5 wt % to about 40 wt %, more
preferably in the range of about 10 wt % to about 30 wt %, and even
more preferably in the range of about 10 wt % to about 25 wt %
relative to the total mass of the fluidized catalytic cracking
catalyst.
[0129] Preferably, the liquefied product(s) and any fluid
hydrocarbon feed flow co-currently in the same direction. The
fluidized catalytic cracking catalyst can be contacted in a
cocurrent-flow, countercurrent-flow or cross-flow configuration
with such a flow of the liquefied product(s) and optionally the
fluid hydrocarbon feed. Preferably the catalytic cracking catalyst
is contacted in a cocurrent flow configuration with a cocurrent
flow of the liquefied product(s) and optionally the fluid
hydrocarbon feed.
[0130] In a preferred embodiment the catalytic cracking step
comprises:
a fluidized catalytic cracking step comprising contacting at least
part of the final liquefied product with a fluidized catalytic
cracking catalyst at a temperature of equal to or more than about
400.degree. C., to produce one or more cracked products and a spent
fluidized catalytic cracking catalyst; a separation step comprising
separating the one or more cracked products from the spent
fluidized catalytic cracking catalyst; a regeneration step
comprising regenerating spent fluidized catalytic cracking catalyst
to produce a regenerated fluidized catalytic cracking catalyst,
heat and carbon dioxide; and a recycle step comprising recycling
the regenerated fluidized catalytic cracking catalyst to the
fluidized catalytic cracking step.
[0131] The fluidized catalytic cracking step is preferably carried
out as described herein before.
[0132] The separation step is preferably carried out with the help
of one or more cyclone separators and/or one or more swirl tubes.
Suitable ways of carrying out the separation step are for example
described in the Handbook titled "Fluid Catalytic Cracking; Design,
Operation, and Troubleshooting of FCC Facilities" by Reza
Sadeghbeigi, published by Gulf Publishing Company, Houston Tex.
(1995), especially pages 219-223 and the Handbook "Fluid Catalytic
Cracking technology and operations", by Joseph W. Wilson, published
by PennWell Publishing Company (1997), chapter 3, especially pages
104-120, and chapter 6, especially pages 186 to 194, herein
incorporated by reference.
[0133] In addition the separation step may further comprise a
stripping step. In such a stripping step the spent fluidized
catalytic cracking catalyst may be stripped to recover the products
absorbed on the spent fluidized catalytic cracking catalyst before
the regeneration step. These products may be recycled and added to
a stream comprising one or more cracked products obtained from the
catalytic cracking step.
[0134] The regeneration step preferably comprises contacting the
spent fluidized catalytic cracking catalyst with an oxygen
containing gas in a regenerator at a temperature of equal to or
more than about 550.degree. C. to produce a regenerated fluidized
catalytic cracking catalyst, heat and carbon dioxide. During the
regeneration coke, that can be deposited on the catalyst as a
result of the fluidized catalytic cracking reaction, is burned off
to restore the catalyst activity.
[0135] The oxygen containing gas may be any oxygen containing gas
known to the skilled person to be suitable for use in a
regenerator. For example the oxygen containing gas may be air or
oxygen-enriched air. By oxygen enriched air is herein understood
air comprising more than about 21 vol. % oxygen (O.sub.2), more
preferably air comprising equal to or more than about 22 vol. %
oxygen, based on the total volume of air.
[0136] The heat produced in the exothermic regeneration step is
preferably employed to provide energy for the endothermic catalytic
cracking step. In addition the heat produced can be used to heat
water and/or generate steam. The steam may be used elsewhere in the
refinery, for example as a liftgas in a riser reactor.
[0137] Preferably the spent fluidized catalytic cracking catalyst
is regenerated at a temperature in the range from equal to or more
than about 575.degree. C., more preferably from equal to or more
than about 600.degree. C., to equal to or less than about
950.degree. C., more preferably to equal to or less than about
850.degree. C. Preferably the spent fluidized catalytic cracking
catalyst is regenerated at a pressure in the range from equal to or
more than about 0.5 bar absolute to equal to or less than about 10
bar absolute (0.05 MegaPascal to 1 MegaPascal), more preferably
from equal to or more than about 1.0 bar absolute to equal to or
less than about 6 bar absolute (0.1 MegaPascal to 0.6
MegaPascal).
[0138] The regenerated fluidized catalytic cracking catalyst can be
recycled to the fluidized catalytic cracking step. In a preferred
embodiment a side stream of make-up fluidized catalytic cracking
catalyst is added to the recycle stream to make-up for loss of
fluidized catalytic cracking catalyst in the reaction zone and
regenerator.
[0139] In the process according to the invention one or more
cracked products are produced. In a preferred embodiment this/these
one or more cracked products is/are subsequently fractionated to
produce one or more product fractions.
[0140] Fractionation may be carried out in any manner known to the
skilled person in the art to be suitable for fractionation of
products from a catalytic cracking unit. For example the
fractionation may be carried out as described in the Handbook
titled "Fluid Catalytic Cracking technology and operations", by
Joseph W. Wilson, published by PennWell Publishing Company (1997),
pages 14 to 18, and chapter 8, especially pages 223 to 235, herein
incorporated by reference.
[0141] In a further embodiment at least one of the one or more
product fractions obtained by fractionation are subsequently
hydrotreated with a source of hydrogen, preferably in the presence
of a hydrotreatment catalyst to produce a hydrotreated product
fraction. The hydrotreatment step may for example comprise
hydrodeoxygenation, hydrodenitrogenation and/or
hydrodesulphurization.
[0142] The one or more product fractions and/or the one or more
hydrotreated product fractions and/or any fractions derived
therefrom can conveniently be used as a biofuel component. Such a
biofuel component may conveniently be blended with one or more
other components to produce a biofuel. Examples of such one or more
other components include anti-oxidants, corrosion inhibitors,
ashless detergents, dehazers, dyes, lubricity improvers and/or
mineral fuel components, but also conventional petroleum derived
gasoline, diesel and/or kerosene fractions.
[0143] By a biofuel is herein understood a fuel that is at least
party derived from a renewable energy source. The biofuel may
advantageously be used in the engine of a transportation
vehicle.
[0144] The examples serve described below further demonstrate
certain aspects of the present invention. The examples are merely
illustrative and not exhaustive, presented to provide a better
understanding of embodiments of the present invention.
EXAMPLES
Example 1
[0145] About 30 grams of birch wood and 1.70 grams of palladium
acetate (Pd(OAc).sub.2) were loaded into a Premex Batch autoclave
of 300 ml equipped with electrical heating, stirrer, injection
system, manometer and temperature recording.
[0146] Stirring was started (300 rpm) and the autoclave was closed.
Stirring speed was increased to 750 rpm and a solution of water (84
g), acetic acid (36 g) and sulphuric acid (0.86 g) was injected.
The autoclave was pressurised with hydrogen (H.sub.2) to 4
MegaPascal (40 bar) and subsequently heated in 70 min to
200.degree. C. Reactor pressure was subsequently increased to 8
MegaPascal (80 bar) by adding H.sub.2. The reaction was continued
for 60 min, occasionally H.sub.2 was added to maintain the pressure
at 8 MegaPascal. The reaction was stopped by rapid cooling to room
temperature (20.degree. C.), subsequently H.sub.2 was vented and
143.2 g of a first total product (including liquid, tar, insoluble
humins and catalyst) was collected. In a duplo experiment applying
identical conditions a second total product (143.7 g) was
prepared.
[0147] The first and second total product were combined. To the
combined total products methyl-tetrahydrofuran (m-THF, 400 grams)
was added. The mixture of methyl-tetrahydrofuran and total products
was stirred for 10 minutes at room temperature (20.degree. C.) and
subsequently filtered over a P3 glass filter to produce a filtrate
and a filter cake.
[0148] The filtrate was stored overnight (about 12 hours) to
facilitate phase separation and produce a top organic layer and a
bottom aqueous layer. The top organic layer was collected.
[0149] The filter cake on the P3 filter were washed with m-THF (300
g) to produce a m-THF solution. The m-THF solution was combined
with the top organic layer. The m-THF was removed from the
combination of top organic layer and m-THF solution by vacuum
distillation at 80.degree. C., 20 mbar (2 KiloPascal) to produce
25.1 grams of a liquefied product. To this liquefied product again
200 g m-THF was added and this solution was subsequently washed
with 10 w % of NaHCO.sub.3 (25 g) and water (25 g). The m-THF was
again removed by vacuum distillation at 80.degree. C., 20 mbar (2
KiloPascal) to produce 23.4 grams of a brownish black coloured
viscous liquefied product.
[0150] The brownish black coloured viscous liquefied product was
characterized by SEC(RI/UV) (size exclusion chromatography with UV
and refractive index detectors), Gas Chromatography and
.sup.13C-Nuclear Magnetic Resonance (.sup.13C-NMR). Elemental
analysis of carbon, hydrogen and oxygen resulted in C, 63.5 w %
(.+-.0.3), H, 7.89 w % (.+-.0.1), 0 (by calculating the balance):
27.3 w % (.+-.0.5). The brownish black coloured viscous liquefied
product had a H/Ceff of 0.85. Total acid number (TAN) was
determined to be (.+-.5) mg KOH/g. The above brownish black
coloured viscous liquefied product was used as a final liquefied
product. A heavy feed mixture comprising long residue was used as a
fluid hydrocarbon co-feed. The final liquefied product was blended
with the fluid hydrocarbon co-feed to prepare a feed mixture
containing a weight percentage of 20 wt % of the final liquefied
product based on the total weight of final liquefied product and
the fluid hydrocarbon co-feed. The feed mixture was injected into
the fluidized catalyst bed of a MAT-5000 fluidized catalytic
cracking unit. The fluidized catalyst bed contained 10 grams of FCC
equilibrium catalyst containing ultra stable zeolite Y. The
fluidized catalyst bed was kept at 520.degree. C. and about 1 bar
absolute (about 0.1 MegaPascal). The run included 7 experiments
with 7 catalyst to feed weight ratios, namely catalyst/feed weight
ratios of 3, 4, 5, 6, 6.5, 7 and 8.
[0151] When compared with a feed consisting of 100 wt % fluid
hydrocarbon co-feed, the feed mixture of final liquefied product
and fluid hydrocarbon co-feed is more reactive. The feed mixture of
final liquefied product and fluid hydrocarbon co-feed shows a
similar yield of valuable products (gasoline, light cycle oil and
LPG) and a similar coke yield when compared to the reference feed.
Detailed results are provided in Table 1.
[0152] The results in table 1 have been normalized and where
applicable are calculated on a dry basis, i.e. without
H.sub.2O.
[0153] For the conversion calculation in table 1, first a corrected
weight of the total feed was calculated by subtracting the weight
of one water molecule for each oxygen atom that has not been
converted into CO or CO2 from the feed. Conversion is subsequently
defined as the weight in grams of drygas+LPG+gasoline+coke divided
by the corrected weight in grams of the total feed. Hence,
conversion=[Weight drygas+LPG+gasoline+coke]/[weight of the total
feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%.
[0154] For the product yield calculation in table 1, first a
corrected weight of the total feed is calculated by subtracting the
weight of one water molecule for each oxygen atom that has not been
converted into CO or CO.sub.2 from the feed. Subsequently the
product yield is defined as the weight in grams of the specific
product divided by the corrected weight in grams of the total feed.
In other words, the product yield distribution is on hydrocarbon
basis. Hence, product yield for product X=[weight X]/[weight of the
total feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%. As water could not be measured
experimentally on the small scale of this example, it is calculated
in table 1 from the measured oxygen content of the feed and
correcting for the measured amounts of CO and CO2 formed. Assuming
that there are no partially converted oxygenates in the product,
this "assumed water yield" then gives the oxygen balance. Hence,
water=[(weight of oxygen in the feed-weight of oxygen in CO and
CO.sub.2)*18/16]/[weight of the total feed]*100%.
TABLE-US-00001 TABLE 1 product after fluidized catalytic cracking
(FCC) of a 100 wt % fluid hydrocarbon co-feed reference feed and
product after FCC of a feed mixture consisting of 20 wt % final
liquefied product and 80 wt % fluid hydrocarbon co-feed (at a
constant cat/oil ratio of 3.0 and a temperature of 520.degree. C.).
20 wt % liquefaction 100 wt % FHCF- product and 80 wt % reference
FHCF Oxygen content in feed mixture 6.5 (wt %) Water (wt %) 6.9
Conversion at Cat/Oil 3 ratio 61.5 62.1 Gasoline yield (wt %) 45.1
44.2 LCO yield (wt %) 25.0 24.4 HCO yield (wt %) 7.3 7.0 Slurry oil
yield (wt %) 6.1 6.1 Coke yield (wt %) 5.8 6.0 LPG yield (wt %) 9.0
10.0 Drygas yield (wt %) 1.6 1.9 CO.sub.2 yield (on C basis) 0.1
0.3 CO yield (wt %) (on C basis) 0.1 0.2 FHCF = Fluid Hydrocarbon
Co-Feed; LCO = Light Cycle Oil; HCO = heavy Cycle Oil, LPG =
liquefied Petroleum Gas.
Example 2
[0155] Furfural respectively furfuryl alcohol was used as an
artificial representative of a final liquefied product. In addition
a heavy feed mixture having a composition as illustrated in tables
2a and 2b was used as a fluid hydrocarbon co-feed.
TABLE-US-00002 TABLE 2a Boiling range distribution of the fluid
hydrocarbon feed as determined by gas chromatography according to
ASTM D2887-06a. wt % .degree. C. wt % .degree. C. wt % .degree. C.
IBP 240 34 410 68 476 2 281 36 414 70 481 4 306 38 417 72 486 6 321
40 421 74 492 8 333 42 425 76 498 10 342 44 428 78 504 12 351 46
432 80 511 14 358 48 435 82 519 16 365 50 438 84 527 18 371 52 442
86 548 20 377 54 445 88 563 22 382 56 449 90 585 24 387 58 453 92
n.d. 26 392 60 458 94 n.d. 28 397 62 462 96 n.d. 30 401 64 467 98
n.d. 32 405 66 471 FBP n.d. n.d: not determined
TABLE-US-00003 TABLE 2b Element analyses of fluid hydrocarbon
co-feed [C] [H] [O] [S] [N] Feed description. [wt %] [wt %] [wt %]
[ppm] [ppm] fluid hydrocarbon co-feed 86.65% 12.65% 0.00% 3360
2220
[0156] The furfural respectively furfuryl alcohol was blended with
the fluid hydrocarbon co-feed to prepare a feed mixture containing
a weight percentage of 20 wt % of furfural respectively furfuryl
alcohol based on the total weight of the feed mixture. The feed
mixture was injected into the fluidized catalyst bed of a MAT-5000
fluidized catalytic cracking unit. The fluidized catalyst bed
contained 10 grams of FCC equilibrium catalyst containing ultra
stable zeolite Y. The fluidized catalyst bed was kept at
520.degree. C. and about 1 bar absolute (about 0.1 MegaPascal). The
catalyst/feed weight ratio was 3.
[0157] The effective molar ratio of hydrogen to carbon
(H/C.sub.eff) of furfural respectively furfuryl alcohol is 0.0
respectively 0.4. By the effective molar ratio of hydrogen to
carbon (H/C.sub.eff) is understood the molar ratio of hydrogen to
carbon after the theoretical removal of all moles of oxygen,
present in the oil on a dry basis, via water production with
hydrogen originally present, presuming no nitrogen or sulphur
present (H/C.sub.eff=(H-2*O)/C).
[0158] The feed mixture comprising furfural respectively furfuryl
alcohol shows a slight decrease of valuable products (gasoline,
light cycle oil and LPG) and a slight increase in coke yield when
compared to the reference feed. Detailed results are provided in
table 2c.
[0159] The below results in table 2c have been normalized and
calculated on a dry basis, i.e. without H.sub.2O.
[0160] For the conversion calculation, first a corrected weight of
the total feed is calculated by subtracting the weight of one water
molecule for each oxygen atom that has not been converted into CO
or CO.sub.2 from the feed. Conversion is subsequently defined as
the weight in grams of drygas+LPG+gasoline+coke divided by the
corrected weight in grams of the total feed. Hence,
conversion=[Weight drygas+LPG+gasoline+coke]/[weight of the total
feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%.
[0161] For the product yield calculation, first a corrected weight
of the total feed is calculated by subtracting the weight of one
water molecule for each oxygen atom that has not been converted
into CO or CO.sub.2 from the feed. Subsequently the product yield
is defined as the weight in grams of the specific product divided
by the corrected weight in grams of the total feed. In other words,
the product yield distribution is on hydrocarbon basis. Hence,
product yield for product X=[weight X]/[weight of the total
feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%. As water could not be measured
experimentally on this small scale, it is calculated from the
measured oxygen content of the feed and correcting for the measured
amounts of CO and CO.sub.2 formed. Assuming that there are no
partially converted oxygenates in the product, this "assumed water
yield" then gives the oxygen balance. Hence, water=[(weight of
oxygen in the feed-weight of oxygen in CO and
CO.sub.2)*18/16]/[weight of the total feed]*100%.
TABLE-US-00004 TABLE 2c product after fluidized catalytic cracking
(FCC) of a 100 wt % fluid hydrocarbon co-feed reference feed and
product after FCC of a feed mixture consisting of 20 wt % furfural
resp. furfuryl alcohol and 80 wt % fluid hydrocarbon co-feed (at a
constant cat/oil ratio of 3.0 and a temperature of 520.degree. C.)
100 wt % 20 wt % 20 wt % Furfuryl FHCF- Furfural + alcohol +
reference 80 wt % FHCF 80 wt % FHCF Oxygen content in feed 0.0 6.7
6.5 (wt %) Conversion (%) 61.9 61.1 62.5 Gasoline yield (wt %) 45.1
40.9 41.7 LCO yield (wt %) 24.4 24.6 23.5 HCO yield (wt %) 7.4 7.3
6.8 Slurry oil yield (wt %) 6.2 6.2 6.0 Coke yield (wt %) 5.7 8.8
8.9 LPG yield (wt %) 9.5 9.5 10.0 Gasoline + LCO + LPG yield 79.1
75.0 75.2 (wt %) Drygas yield (wt %) 1.7 1.8 1.9 CO2 yield (wt % on
C 0.0 0.1 0.1 basis) CO yield (wt % on C basis) 0.0 0.3 0.3 FHCF =
Fluid Hydrocarbon Co-Feed; LCO = Light Cycle Oil; HCO = heavy Cycle
Oil, LPG = liquefied Petroleum Gas.
[0162] Example 2, further shows the advantage of co-feeding a
complete final liquefied product, which is a mixture of several
components, to the FCC unit, rather than a feed containing only
furfural or furfuryl alcohol.
Example 3
[0163] Respectively tetrahydrofuran (THF), butanone and 2-butanol
were used as an artificial representative of a final liquefied
product. In addition a vacuum gas oil (VGO) was used as a fluid
hydrocarbon co-feed.
[0164] The tetrahydrofuran (THF), butanone or 2-butanol
respectively was blended with the fluid hydrocarbon co-feed to
prepare a feed mixture containing a weight percentage of 20 wt % of
tetrahydrofuran (THF), butanone or 2-butanol respectively, based on
the total weight of the feed mixture. The feed mixture was injected
into the fluidized catalyst bed of a MAT-5000 fluidized catalytic
cracking unit. The fluidized catalyst bed contained 10 grams of FCC
equilibrium catalyst containing ultra stable zeolite Y. The
fluidized catalyst bed was kept at 550.degree. C. and about 1 bar
absolute (about 0.1 MegaPascal). The catalyst/feed weight ratio was
3.
[0165] The effective molar ratios of hydrogen to carbon
(H/C.sub.eff) of tetrahydrofuran (THF), butanone and 2-butanol
respectively are 1.5, 1.5 and 2.0 respectively.
[0166] The feed mixture comprising respectively tetrahydrofuran
(THF), butanone or 2-butanol shows a similar yield of valuable
products (gasoline, light cycle oil and LPG) and for butanone and
2-butanol even a decrease in coke yield compared to the reference
feed. Detailed results are provided in table 3.
TABLE-US-00005 TABLE 3 product after fluidized catalytic cracking
(FCC) of a 100 wt % fluid hydrocarbon co-feed reference feed and
product after FCC of a feed mixture consisting of 20 wt % THF,
butanone or 2-butanol respectively and 80 wt % fluid hydrocarbon
co-feed (at aconstant cat/oil ratio of 3.0 and a temperature of
550.degree. C.) 20 wt % 20 wt % 20 wt % 100 wt % THF + Butanone +
2-Butanol + FHCF- 80 wt % 80 wt % 80 wt % reference* FHCF* FHCF*
FHCF* Oxygen content in feed 0.0 4.3 4.4 4.4 (wt %) Conversion (%)
59.1 61.9 60.6 63.7 Gasoline yield (wt %) 40.7 37.0 39.3 39.8 LCO
yield (wt %) 28.7 25.9 27.4 25.4 HCO yield (wt %) 7.0 6.7 6.8 6.2
Slurry oil yield (wt %) 5.2 5.4 5.1 4.7 Coke yield (wt %) 3.9 5.6
4.0 3.2 LPG yield (wt %) 11.8 15.7 14.5 18.2 Gasoline + LCO + LPG
81.2 78.6 81.2 83.4 yield (wt %) Drygas yield (wt %) 2.8 3.7 2.8
2.5 CO2 yield (wt % on C 0.00 0.01 0.01 0.00 basis) CO yield (wt %
on C 0.00 0.03 0.00 0.00 basis) FHCF = Fluid Hydrocarbon Co-Feed;
LCO = Light Cycle Oil; HCO = heavy Cycle Oil, PG = liquefied
Petroleum Gas.
[0167] The above results in table 3 have been normalized and
calculated on a dry basis, i.e. without H.sub.2O.
[0168] For the conversion calculation, first a corrected weight of
the total feed is calculated by subtracting the weight of one water
molecule for each oxygen atom that has not been converted into CO
or CO.sub.2 from the feed. Conversion is subsequently defined as
the weight in grams of drygas+LPG+gasoline+coke divided by the
corrected weight in grams of the total feed. Hence,
conversion=[Weight drygas+LPG+gasoline+coke]/[weight of the total
feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%.
[0169] For the product yield calculation, first a corrected weight
of the total feed is calculated by subtracting the weight of one
water molecule for each oxygen atom that has not been converted
into CO or CO.sub.2 from the feed. Subsequently the product yield
is defined as the weight in grams of the specific product divided
by the corrected weight in grams of the total feed. In other words,
the product yield distribution is on hydrocarbon basis. Hence,
product yield for product X=[weight X]/[weight of the total
feed-(weight of oxygen in feed-weight of oxygen in CO and
CO.sub.2)*18/16]*100%. As water could not be measured
experimentally on this small scale, it is calculated from the
measured oxygen content of the feed and correcting for the measured
amounts of CO and CO.sub.2 formed. Assuming that there are no
partially converted oxygenates in the product, this "assumed water
yield" then gives the oxygen balance. Hence, water=[(weight of
oxygen in the feed-weight of oxygen in CO and
CO.sub.2)*18/16]/[weight of the total feed]*100%.
[0170] Further modifications and alternative embodiments of various
aspects of the invention will be apparent to those skilled in the
art in view of this description. Accordingly, this description is
to be construed as illustrative only and is for the purpose of
teaching those skilled in the art the general manner of carrying
out the invention. It is to be understood that the forms of the
invention shown and described herein are to be taken as the
presently preferred embodiments. Elements and materials may be
substituted for those illustrated and described herein, parts and
processes may be reversed, and certain features of the invention
may be utilized independently, all as would be apparent to one
skilled in the art after having the benefit of this description of
the invention. Changes may be made in the elements described herein
without departing from the spirit and scope of the invention as
described in the following claims
* * * * *