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Title:
BIOFUEL PRODUCTION USING DOPED ZEOLITE CATALYST
Document Type and Number:
WIPO Patent Application WO/2017/066521
Kind Code:
A1
Abstract:
A method of converting biovapors to biofuel includes directing biovapors derived from decomposition of biomass, said biovapors comprising at least C5 and C6 compounds, into a catalytic reaction chamber separate from the decomposed biomass; and contacting the biovapors with a catalyst composition comprising phosphorus and zeolite. The zeolite can be a nanozeolite. The catalyst results in lower coke formation and lowers the oxygen content of the fuel produced compared to a catalyst that does not contain phosphorus.

Inventors:
MALYALA RAJASHEKHARAM (US)
WAN HAIJUN (US)
MANZER LEO E (US)
WHITE JAMES F (US)
GAFFNEY ANNE M (US)
Application Number:
PCT/US2016/056977
Publication Date:
April 20, 2017
Filing Date:
October 14, 2016
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
COOL PLANET ENERGY SYSTEMS INC (US)
International Classes:
B01J29/85; C10G3/00
Foreign References:
US20140069799A12014-03-13
US6395949B12002-05-28
US20130000183A12013-01-03
US20130317271A12013-11-28
US7507685B22009-03-24
Attorney, Agent or Firm:
SCOZZAFAVA, Mary Rose et al. (US)
Download PDF:
Claims:
CLAIMS

1. A method of converting biovapors to biofuel, comprising: directing biovapors derived from decomposition of biomass, said biovapors comprising at least C5 and C6 compounds, into a catalytic reaction chamber separate from the decomposed biomass; and contacting the biovapors with a catalyst composition comprising a phosphorus- containing zeolite catalyst.

2. A method of converting biovapors to biofuel, comprising: combining biomass with a catalyst composition comprising a phosphorus-containing zeolite catalyst; pyrolyzing the biomass to form biovapors, said biovapors comprising at least C5 and C6 compounds; and contacting the biovapors with the catalyst composition comprising a phosphorus- containing zeolite catalyst.

3. The method of claim 1 or 2, wherein the phosphorus-containing zeolite has a phosphorous content in the range from 0.1% to 10% by weight relative to the total zeolite/binder.

4. The method of claim 1 or 2, wherein the phosphorus-containing zeolite has a phosphorous content in the range from 0.5% to 5% by weight relative to the total zeolite/binder.

5. The method of claim 1-4, wherein the zeolite catalyst comprises a nano-zeolite.

6. The method of claim 5, wherein at least 60% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

7. The method of claim 5, wherein at least 80% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

8. The method of claim 5, wherein at least 90% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

9. The method of any of claims 5-8, wherein at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

10. The method of any of claims 5-8, wherein at least 40% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

11. The method of any of claims 5-8, wherein at least 50% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

12. The method of any of claims 5-8, wherein nanozeolite crystallite has a silica to alumina ratio in the range of 50-250.

13. The method of claims 1-12, wherein the zeolite is one or more zeolites selected from the group consisting of ZSM-5, beta-zeolite, modernite, and zeolite-Y.

14. The method of claims 1-12, wherein the biovapors are contacted with a catalyst composition heated at a temperature in the range of 350°C-500°C.

15. The method of any of claims 1-13, wherein contacting the biovapors with a

catalyst composition comprises sequentially contacting the biovapors with one or more catalysts compositions, at least one of which comprises the phosphorus- containing zeolite catalyst.

16. The method of claims 3, wherein the first catalyst comprises a phosphorus- containing nanozeolite, and wherein the second catalyst comprises a nanozeolite catalyst, wherein at least 90% of the nanozeolite crystallites have a largest dimension of less than or equal to 200 μηι.

17. The method of claims 14, wherein both the first and second catalysts comprises a phosphorus-containing nanozeolite.

18. The method of claim 16, wherein the catalyst compositions are different.

19. The method of claim 16, wherein the catalyst compositions are the same.

20. The method of claim 14-18, wherein the catalyst compositions are subjected to different reaction conditions.

21. The method of claim 19, wherein the temperature of the catalyst conditions are different.

22. The method of claim 19, wherein the temperature of the first catalyst composition is lower than the temperature of the second catalyst composition.

23. The method of any of claims 1-20, wherein the biovapors are obtained from a decomposition process selected from chemical, thermal and biological decomposition processes.

24. The method of claim 21, wherein the thermal process comprises pyrolysis.

25. The method of claim 21, wherein the chemical process comprises acid hydrolysis.

26. The method of claim 21, wherein pyrolysis comprises heating biomass at

temperatures of less than 600°C to generate pyrolysis vapors.

27. The method of claim 21, wherein water or steam, C02, air, 02, or their

combinations is injected into biomass during pyrolysis.

28. The method of any of claims 1-25, wherein the fuel yield is greater than 6.5%, or greater than 7.0%> or greater than 7.5%>, or greater than 8.0%> or greater than 8.5%> by weight of input biomass, or in the range of 6.5-12%) by weight of input biomass.

29. The method of claim 26, wherein the coke yield is less than 5 wt%>, or less than 4 wt%>, or less than 3 wt%> or even less than 2 wt%> by weight of input biomass or in the range of 1-5 wt%> of input biomass.

30. A phosphorous containing ZSM-5 nano-zeolite, wherein at least 60%> of the

crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μπι, wherein the phosphorous content is in the range from 0.1%> to 10%> by weight relative to the total zeolite/binder.

31. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein the phosphorous content is in the range from 0.5% to 5% by weight relative to the total zeolite/binder.

32. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein the

phosphorus is inside or outside the zeolite framework.

33. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein the

phosphorus is impregnated on the zeolite.

34. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein the

phosphorus is introduced into the zeolite by incipient wetness technique.

35. The phosphorous containing ZSM-5 nano-zeolite of claim 32, wherein the source of phosphorus is selected from the group selected from phosphoric acid, ortho phosphates, poly phosphates, ammonium phosphate, di-ammonium phosphates, mono, di and tri phenyl phosphates, organo phosphates, and sodium phosphates or any mixtures thereof.

36. The phosphorous containing ZSM-5 nano-zeolite of claim 32, wherein the

phosphorous source is a salt of phosphoric acid or phosphoric acid itself or any combinations thereof.

37. The phosphorous containing ZSM-5 nano-zeolite of claim 32, wherein the

phosphorous source comprises phosphoric acid.

38. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 60%) of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

39. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 80%) of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

40. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 90%) of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

41. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

42. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 40%) of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

43. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein at least 50%) of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

44. The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein nanozeolite crystallite has a silica to alumina ratio in the range of 50-250.

Description:
BIOFUEL PRODUCTION USING DOPED ZEOLITE CATALYST

CROSS-REFERENCE(S) TO RELATED APPLICATIONS

[0001] The present application claims the benefit of priority under 35 U.S.C §119(e) to co-pending United States application Ser. No. 62/242,466, filed on October 16, 2015, the contents of which are hereby incorporated by reference herein in its entirety.

[0002] The present application is related to United States Patent Application No.

62/191166 filed on July 10, 2015, the contents of which are hereby incorporated by reference herein in its entirety.

INCORPORATION BY REFERENCE

[0003] All patents, patent applications and publications cited herein are hereby incorporated by reference in their entirety in order to more fully describe the state of the art as known to those skilled therein as of the date of the invention described herein.

TECHNICAL FIELD

[0004] The present disclosure relates generally to catalysts and processes for use in making renewable fuels, and more particularly to catalysts for the chemical conversion of biomass to renewable fuels and other useful chemical compounds.

BACKGROUND

[0005] Zeolites have been known for some time as catalysts in hydrocarbon conversions. Zeolites are crystalline aluminosilicates with a characteristic porous structure made up of a three dimensional network of Si0 4 and A10 4 tetrahedra cross-linked by shared oxygen atoms with a variety of structures and aluminum contents. Other atoms can be incorporated into the zeolite lattice, such as phosphorus, germanium, gallium or boron. The catalytic activity of zeolites relies on their acidity. Non-tetravalent atoms within the tetrahedral array, such as trivalent aluminum, gallium or boron, create a positive charge deficiency, which can be compensated by a cation such as H + , ammonium, etc. In addition, the pores and channels through the crystalline structure of the zeolite enable the materials to act as selective molecular sieves particularly if the dimensions of the channels fall within a range which enables the diffusion of large molecules to be controlled. Thus, acidic zeolites can be used as selective catalysts.

[0006] Zeolites have been used for the conversion of organic molecules into gasoline range hydrocarbons. Methanol or ethanol can be converted to gasoline range of

hydrocarbons via dehydration and oligomerization. H-ZSM-5 (10-membered ring) is used as a catalyst for methanol to gasoline process by ExxonMobil Research and Engineering Company in the MTG (methanol to gasoline) process.

[0007] Numerous processes have been investigated for the conversion of biomass feedstocks into biofuel. Such processes include gasification, slow pyrolysis and fast pyrolysis. The products from these reactions tend to be of low quality and are not useful, without significant post-processing, as transportation fuels. In particular, catalytic fast pyrolysis employs pyrolysis of biomass over a catalyst in a single reactor. The pyrolysis takes place at high temperatures, e.g., greater than 600°C, and results in of low aromatic yield and unacceptably high coking (greater than 30% and even greater than 50%).

[0008] Systems describing the catalytic conversion of biomass into fuels and other useful chemical compounds also have been previously described. Some such methods involve subjecting volatile components derived from biomass to one or more catalysts such as dehydration catalysts, aromatization catalysts, and gas upgrading catalysts. The process products tend to be of better quality than the simple thermal processes. However, the same catalyst used for gasoline formation can also lead to polymerization of olefins leading to coking, e.g., the build- up of a high carbon content residue on the zeolite catalyst sites and the deactivation of the catalyst. Coking can increase the frequency of catalyst reactivation, increasing production costs and reducing yield and productivity.

[0009] Catalytic processes for conversion of biomass to biofuel that improve catalyst life, reduce coking and increase fuel yield are desired.

SUMMARY

[0010] A phosphorus doped zeolite catalyst for use in the production of biofuel from biomass is described. In one aspect, a method of converting biovapors to biofuel includes directing biovapors derived from decomposition of biomass, said biovapors including at least C5 and C6 compounds, into a catalytic reaction chamber separate from the decomposed biomass; and contacting the biovapors with a catalyst composition including a phosphorus containing zeolite. The zeolite can be a nanozeolite.

[0011] In one or more embodiments, the catalyst containing phosphorous and zeolite lowers the rate at which the catalyst cokes and also lowers the oxygen content of the fuel generated from biovapors, while maintaining the same amount of raw fuel obtained in comparison with a catalyst that does not contain phosphorous. Lowering of fuel oxygen content and coke weight on the catalyst is beneficial while converting biomass and biovapors to liquid fuels.

[0012] In one aspect, a method of converting biovapors to biofuel includes directing biovapors derived from decomposition of biomass, said biovapors comprising at least C5 and C6 compounds, into a catalytic reaction chamber separate from the decomposed biomass; and contacting the biovapors with a catalyst composition comprising a phosphorus-containing zeolite catalyst.

[0013] In another aspect, a method of converting biovapors to biofuel includes combining biomass with a catalyst composition comprising a phosphorus-containing zeolite catalyst; pyrolyzing the biomass to form biovapors, said biovapors containing at least C5 and C6 compounds; and contacting the biovapors with the catalyst composition containing a phosphorus-containing zeolite catalyst.

[0014] In one or more embodiments, the phosphorus-containing zeolite has a phosphorous content in the range from 0.1% to 10% by weight relative to the total zeolite/binder.

[0015] In one or more embodiments, the phosphorus-containing zeolite has a phosphorous content in the range from 0.5% to 5% by weight relative to the total zeolite/binder.

[0016] In one or more embodiments, the zeolite catalyst includes a nano-zeolite.

[0017] In one or more embodiments, at least 60% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μπι.

[0018] In one or more embodiments, at least 80% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μπι. [0019] In one or more embodiments, at least 90% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

[0020] In one or more embodiments, at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

[0021] In one or more embodiments, at least 40% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

[0022] In one or more embodiments, at least 50% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

[0023] In one or more embodiments, nanozeolite crystallite has a silica to alumina ratio in the range of 50-250.

[0024] In one or more embodiments, the biovapors are contacted with a catalyst composition heated at a temperature in the range of 350°C-500°C.

[0025] In one or more embodiments, the separate reaction chamber can contain one or more catalytic reactors.

[0026] In one or more embodiments, contacting the biovapors with a catalyst composition comprises sequentially contacting the biovapors with one or more catalysts compositions, at least one of which comprises the phosphorus-containing zeolite catalyst.

[0027] In another aspect the first catalyst includes a phosphorus-containing nanozeolite, and wherein the second catalyst comprises a nanozeolite catalyst, wherein at least 90% of the nanozeolite crystallites have a largest dimension of less than or equal to 200 μηι.

[0028] In one or more embodiments, where one or more catalysts includes a phosphorus- containing nanozeolite.

[0029] In one or more embodiments, the catalyst compositions are different.

[0030] In one or more embodiments, the catalyst compositions are the same.

[0031] In one or more embodiments, the catalyst compositions are subjected to different reaction conditions. [0032] In one or more embodiments, the temperature of the catalyst conditions are different.

[0033] In one or more embodiments, the temperature of the first catalyst composition is lower than the temperature of the second catalyst composition.

[0034] In one or more embodiments, the biovapors are obtained from a decomposition process selected from chemical, thermal and biological decomposition processes.

[0035] In one or more embodiments, the thermal process includes pyrolysis.

[0036] In one or more embodiments, the chemical process includes acid hydrolysis.

[0037] In one or more embodiments, pyrolysis includes heating biomass at temperatures of less than 600°C to generate pyrolysis vapors.

[0038] In one or more embodiments, water or steam or C0 2 is injected into biomass during pyrolysis.

[0039] In one or more embodiments, the fuel yield is greater than 6.5%, or greater than 7.0% or greater than 7.5%, or greater than 8.0%> or greater than 8.5%> by weight of input biomass, or in the range of 6.5-12%) by weight of input biomass.

[0040] In one or more embodiments, the coke yield is less than 5 wt%>, or less than 4 wt%>, or less than 3 wt%> or even less than 2 wt%> by weight of input biomass or in the range of 1-5 wt%> of input biomass.

[0041] In one or more of the embodiments, the zeolite can be selected from the group consisting of ZSM-5, beta, modernite and Y. In another aspect, a phosphorous containing ZSM-5 nano-zeolite is provided containing a zeolite and a binder, wherein at least 60%> of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μπι, wherein the phosphorous content is in the range from 0.1%> to 10%> by weight relative to the total zeolite/binder.

[0042] The phosphorous containing ZSM-5 nano-zeolite of claim 28, wherein the phosphorous content is in the range from 0.5% to 5% by weight relative to the total zeolite/binder. [0043] In one or more embodiments, the phosphorus is inside or outside the zeolite framework.

[0044] In one or more embodiments, the phosphorus is impregnated on the zeolite.

[0045] In one or more embodiments, the phosphorus is incorporated into or onto the zeolite by well-known incipient wetness technique.

[0046] In one or more embodiments, the source of phosphorus is selected from the group selected from phosphoric acid, ortho phosphates, poly phosphates, ammonium phosphate, di- ammonium phosphates, mono, di and tri phenyl phosphates, organo phosphates, sodium and phosphates or any mixtures thereof.

[0047] In one or more embodiments, the phosphorous source is a salt of phosphoric acid or phosphoric acid itself or any combinations thereof.

[0048] In one or more embodiments, the phosphorous source includes phosphoric acid.

[0049] In one or more embodiments, at least 60% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

[0050] In one or more embodiments, at least 80% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

[0051] In one or more embodiments, at least 90% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μιη.

[0052] In one or more embodiments, at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

[0053] In one or more embodiments, at least 40% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μιη.

[0054] In one or more embodiments, at least 50% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μηι.

[0055] In one or more embodiments, nanozeolite crystallite has a silica to alumina ratio in the range of 50-250. [0056] It is contemplated that embodiments can be variously combined or separated without parting from the invention.

[0057] These and other aspects and embodiments of the disclosure are illustrated and described below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The invention is described with reference to the following figures, which are presented for the purpose of illustration only and are not intended to be limiting.

In the Drawings:

[0059] Figure 1 is a schematic representation of the reaction system used to generate biofuel and incorporating a phosphorus-containing catalyst according to one or more embodiments.

[0060] Figure 2 is a plot of fuel yield over time for an exemplary system and method used to generate biofuel.

[0061] Figure 3 is a plot of oxygen content in raw fuel over time for an exemplary system and method used to generate biofuel.

[0062] Figure 4 is a bar graph illustrating coke yields and coke distribution in guard bed and BTX bed according to one or more embodiments.

[0063] Figure 5 is a plot of reformate yield versus the three different types of catalyst combinations investigated according to one or more embodiments..

[0064] Figure 6 is a plot of oxygen content in the distilled reformate versus the three different types of catalyst combinations investigated according to one or more embodiments.

DETAILED DESCRIPTION

[0065] The specification discloses compositions and methods for the production of aromatic and olefinic compounds, and more specifically biofuels, using a decomposition process to generate biovapors from biomass and a catalytic process to convert the biovapors into biofuels. In other embodiments, processes for converting biovapors into fuel in a high yield, low coking process are disclosed.

[0066] In one aspect, certain catalysts or combination of catalysts have been discovered that can reduce coke formation and/or control product formation (e.g., higher production of aromatics and/or olefins relative to other fuels) without compromise to fuel yields, as compared to processes using conventional catalysts. In other aspects, biofuel manufacturing processes and systems are disclosed that, in combination with catalysts or combination of catalysts described herein, lower yields of coke formation and/or provide more controlled product formation (e.g., higher production of aromatics and/or olefins relative to other fuel as compared to processes lacking these reaction conditions.

[0067] In one aspect, a method for producing biofuels or biofuel components from biovapors employs a catalyst composition comprising a phosphorus containing zeolite. In one or more embodiments, the zeolite is a nanozeolite. In one or more embodiments, the zeolite is a ZSM-5 nanozeolite. The phosphorus containing zeolite catalyst can have a phosphorus content of 0.1 wt% to 10 wt% and in some embodiments the phosphorous content is in the range of 0.5 wt% to 5 wt%. The phosphorus can be inside or outside the zeolite framework. As used herein, the weight percent is calculated relative to the total

zeolite/binder.

[0068] "Biofuel" as used herein is understood to mean a composition derived from a non- petroleum biomass having a mixture of hydrocarbons in the correct chain lengths, chain conformations, and compound ratios to be used as a fuel or a fuel component. A fuel is a composition useful as a fuel in internal combustion engines, such as commonly found in transportation vehicles (e.g., automobiles, airplanes, trains, and heavy machinery), the composition including, but not limited to, a composition classifiable as a jet engine fuel, a diesel engine fuel, or a gasoline engine fuel. A "fuel component" is a composition containing some or all of the components of a fuel (in the same or different proportions from those found in a fuel) that can be blended with other ingredients to obtain a fuel.

[0069] Coke is defined as carbonaceous matter deposited on the catalyst. It is well known that coke generally has more carbon than hydrogen. It may also contain poly aromatic hydrocarbons and other complex organic compounds rich in carbon and deficient in hydrogen. In general, coke increases as the zeolite catalysts acidity increases. However, the same acidity is needed to perform the relevant conversion. Thus in zeolite catalysis, it is a fine balance between avoiding coke formation and increasing the needed catalyst acidity. Further to this, certain acidic sites in zeolites promote coking, while certain acidic sites promote necessary conversion to fuel molecules. During biomass pyrolysis, the oxygen in biomass is rejected as water, CO and C0 2 . When rejected as water, each oxygen atom pulls two hydrogen atoms to form the water molecule, thereby further reducing the availability of hydrogen, to an already lower levels of hydrogen in biomass. This overall deficiency of hydrogen lowers fuel production and increases coke formation on the catalyst. To revive catalysts activity, the catalyst is then subject to periodic precise heating in the presence of known amount of air and/or oxygen, to burn the carbonaceous matter that has been deposited as coke on the catalyst. The amount of coke burnt can then be deduced by subtracting the weight of the spent catalyst before and after such a burning event of the carbonaceous matter. The percentage of biomass that has resulted in coke formation can then be deduced from the amount of coke burnt to the amount of biomass used.

[0070] It has been surprisingly discovered that the catalysts for biomass to biofuel conversion including a phosphorus-containing zeolite provide lower yields of coke formation and/or provide more controlled product formation (e.g., higher production of aromatics and/or olefins relative to other fuels) without compromise to fuel yield, as compared to processes using conventional catalysts. Thus, for example, the fuel yield can be greater than 6.5%, or greater than 7.0% or greater than 7.5%, or greater than 8.0%> or greater than 8.5%> by weight of input biomass, or in the range of 6.5-12%) by weight of input biomass, without increase in coke formation (e.g., less than 5 wt, or less than 4 wt%>, or less than 3 wt%> or even less than 2 wt%> by weight of input biomass).

[0071] In one aspect, the method of converting biovapors to biofuel includes directing biovapors derived from decomposition of biomass into a catalytic reaction chamber. The decomposition process is selected to produce an oxygenated feedstock rich in C5 and C6 compounds, such as sugars and anhydrosugars. The biovapors contact and react with a catalyst composition including a phosphorus-containing zeolite. The catalyst composition can also include a nanozeolite having a crystallite size and a silica to alumina ratio (SAR) selected to maximize fuel yield. Catalyst

[0072] It has been surprisingly discovered that a zeolite catalyst that contains phosphorus can produce biofuels with high yields and low amounts of coking. The zeolite catalyst can contain phosphorus in the zeolite lattice. That is, the zeolite is doped with phosphorus. In other embodiments, the phosphorus decorates the zeolite framework and the phosphorus can be found on the inside or outside of the zeolite framework, or both. In still other

embodiments, the phosphorus is impregnated on the zeolite. The phosphorous can be in the oxide form, especially after calcination in air. The phosphorus containing zeolite catalyst can have a phosphorus content of 0.1 wt% to 10 wt% relative to the total zeolite/binder, and in some embodiments the phosphorous content is in the range of 0.5 wt% to 5 wt% relative to the total zeolite/binder.

[0Θ73] Ion exchange means the protonic sites of the zeolite are exchanged with ions.

Impregnated zeolite means that the metals are deposited on the zeolite and can be anywhere within the zeolite unlike ion-exchange. As these are different locations in the zeolite, they result in different activities along with differences in physical and chemical properties. Also on a few percent of metal can be ion exchanged on the zeolite as it depends on the ion- exchange capacity of the material or the number of protonic sites on the zeolite. This is usually less than 5%. On the other hand, more material can be loaded while impregnation method as the metal can be anywhere in the catalyst.

[0074] In one or more embodiments, the zeolite is a nanozeolite. As defined herein a nanozeolite is a zeolite in which at least 60% of the nanozeolite catalyst crystallites have a largest dimension of less than 200 μπι. In other embodiments, at least 70% or at least 80%> or at least 90% or at least 95% of the nanozeolite catalyst crystallites have a largest dimension of less than or equal to 200 μπι or any range bounded by any stated value. In one or more embodiments, at least 25% of the nanozeolite catalyst crystallites have a largest dimension of less than or equal to 100 μηι. In other embodiments, at least 40% or at least 50% of the nanozeolite catalyst crystallites have a largest dimension of less than or equal to 100 μπι or any range bounded by any value stated. In one particular catalyst composition, at least 90% of the zeolite crystallites have a largest dimension of less than 200 μπι and at least 50% of the zeolite crystallites have a largest dimension of less than or equal to 100 μηι. In some embodiments, the zeolite has an average crystallite size of between Ι μηι and 2 μηι, or between 750 nm and 1 μηι, or between 500nm and 750 nm, or between 250 nm and 500 nm, or between 125 and 250 nm, or between 25 and 125 nm or any range bounded by any value stated herein. In one particular embodiment, the zeolite has an average crystallite size in the range of 250 nm-2 μιη. In other embodiments, at least 50% or at least 60% or at least 70% or at least 80% or at least 90% of the nanozeolite catalyst crystallites have a largest dimension in the range of 250 nm-2 μιη. In one or more embodiments, the zeolite crystallite size is predominantly less than 1 micron, or less than 900 nm, or less than 800 nm, or less than 700 nm or less than 600 nm, or less than 500 nm, or less than 200 nm, less than 150 nm, less than 100 nm and even less than 50 nm and as small as 40 nm or any range bounded by any of the stated values.

[0075] Zeolite materials are typically provided as particles, which can be further incorporated into the extrudate catalyst compositions described herein. Although the particles can be on the micron scale, e.g., 10 μιη-500 μιτι, or 50-300 μιτι, or 100-200 μιη average particle size, the particles can encompass a number of smaller crystalline domains or crystallites. These crystallites contain the active domains that are the sites for catalytic activity.

[0076] In one or more embodiments, the catalyst provides a fuel yield of at least 6.5 wt% (preferably 7-8 wt%) based on processed biomass and/or a coking rate of less than 3 wt% (preferably 1-2 wt%) based on processed biomass. In one or more embodiments, the fuel yield is attained at very low coking levels (e.g., less than 5 wt, or less than 4 wt%, or less than 3 wt% or even less than 2 wt% by weight of input biomass).

[0077] In one or more embodiments, the nanozeolite has a silica to alumina ratio (SAR) in the range of 50 to 180 and the nanozeolite catalyst has a zeolite crystallite size elected to provide a fuel yield of at least 6.5 wt% (preferably 7-8 wt%) based on processed biomass and/or a coking rate of less than 3 wt% (preferably 1-2 wt%) based on processed biomass. In one or more embodiments, the alumina ratio (SAR) is in the range of 50 to 250 (mol/mol), or 80 to 200 (mol/mol), or 90 to 180 (mol/mol), or 120 to 150(mol/mol) or any range bounded by any of the stated values.

[0078] The catalyst composition used in the conversion of biomass to biofuel according to one or more embodiments can be in the form of an extrudate, e.g., extruded pellets, and the extrudate can include a zeolite catalyst and a non-zeolite binder. The catalyst composition includes a zeolite having a microporous crystalline phase distributed in a non-zeolite binder in a configuration that provides mesoporosity and macroporosity. The zeolite catalyst is a nanozeolite. For clarity, reference to a "catalyst composition," "zeolite composition" or "zeolite catalyst composition" means a catalyst composition containing both a zeolite material and a non-zeolite binder. Reference to "zeolite" or "zeolite catalyst" refers to the zeolite materials used in the catalyst composition.

[0079] The zeolite in the catalyst composition can be greater than or equal to 50 wt% of the composition. In some embodiments, the zeolite makes up no more than 80 wt% of the final catalyst composition, and in a particular embodiment, the zeolite makes up about 55-70 wt%, or about 60-65 wt%, of the final catalyst composition.

[0080] The particular zeolite for inclusion in the catalyst composition can be selected from those used in liquid fuel production from oxyhydrocarbon feedstocks. The zeolite can be selected with consideration of the particular chemical reactions and the natures of feedstock contemplated. The zeolite provides nano- and microporous crystalline walls with desirable active sites, which provide the desired shape selectivity and reaction time to convert the oxygenated sugar-based feedstock into biofuels and fuel components.

[0081] In one or more embodiments, the zeolite can be ZSM-5, beta-, modernite, and zeolite-Y. The zeolite can be doped with other metals at either the Si or Al site, for example, with one or more of gallium (Ga), lanthanum (La), zinc (Zn), chromium (Cr), iron (Fe) or vanadium (V). In particular, the zeolite can be ZSM-5, an aluminosilicate zeolite belonging to the pentasil family of zeolites. ZSM-5 has a high silicon to aluminum ratio and is acidic with the use of protons to keep the material charge-neutral. In one or more embodiment, the silica alumina ratio in the zeolite catalyst in is the range of 50 to 250 (mol/mol). In specific embodiments, the silica alumina ratio in the zeolite catalyst is the range of 50 to 180

(mol/mol) or 90 to 150 (mol/mol). In one or more embodiments, the alumina ratio (SAR) is in the range of 50 to 250 (mol/mol), or 80 to 200 (mol/mol), or 90 to 180 (mol/mol), or 120 to 150 (mol/mol) or any range bounded by any of the stated values. The ZSM-5 can be doped with other metals at either the Si or Al site, for example, with one or more of gallium (Ga), lanthanum (La), zinc (Zn), chromium (Cr), iron (Fe) or vanadium (V).

[0082] The selected zeolite can be treated as described herein to incorporate phosphorus into the zeolite catalyst. In one or more embodiment, the zeolite includes up to 10 wt% phosphorus relative to the total zeolite/binder. [0083] The non-zeolite binder material can be selected to impart desirable thermal and mechanical properties, among others, to the zeolite catalyst composition. In one or more embodiments, the non-zeolite binder material is an inorganic oxide, such as silica, titania, zirconia, talc, magnesia, alumina, silica-alumina, calcium oxide, kaolin, clays and

combinations of thereof. In one or more embodiments, the non-zeolite binder material is an alumina-containing crystalline material. In particular, the non-zeolite binder material can be a clay, e.g., a kaolin clay. The non-zeolite binder can further include alumina (aluminum oxide). In one or more embodiments, the low bulk density zeolite catalyst is a blend of ZSM- 5 zeolite with kaolin clay and alumina oxide as a binder. The relative amounts of zeolite and non-zeolite binder can vary. The amount of zeolite in the catalyst composition can vary from 50 to 80% and the amount of non-zeolite binder can vary from 10% to 40%.

[0084] In one or more embodiments, the catalyst composition has a narrow size distribution of mesopore-scale pore volume. For example, the mesopore-scale pore volume can have an average pore diameter of 20 A to 500 A. The total pore volume can be in the range of 0.2-0.8 mL(cm3)/g. In other embodiments, the zeolite crystals/particles are uniformly distributed within the non-zeolite binder and have a mesoporosity defined as an average pore size in the range of 20 to 500 Angstroms with an average total pore volume between 0.3 to 0.6 cm3/g. In some embodiments, the catalyst composition used in the conversion of biomass to biofuel can have an average mesopore diameter of 50 A to 100 A, and an average total pore volume of at least 0.4 mL/g.

[0085] The catalyst composition also includes nanoporosity, which arises from the zeolite structure itself. For example, the zeolite cage molecule forms pore opening on the range of a few angstroms, e.g. 5-10 A. These pore provide shape selectivity, for example, permitting access to feedstock molecules of certain sizes, while excluding larger molecules. In additions, the acidity, which varies with the SAR, can effect oxygen removal and

aromatization.

[0086] A catalyst composition containing at least 50% by weight of a phosphorus- containing nanozeolite catalyst, such as ZSM-5, optionally with a silica alumina ratio between 90 and 250, exhibits lower coking propensity and longer cycle times in converting biomass vapors to gasoline, diesel and jet range hydrocarbons as compared to conventional catalyst composition, e.g., when compared to catalyst that does not meet the suggested criteria of silica alumina ratio and particle size. Catalyst Synthesis

[0087] The catalyst composition can be prepared, in particular with reference to the specified micro-, meso- and macroporosity, by combining the zeolite catalyst and non-zeolite binder, with pore formers that create macro-porosity in the final extruded catalyst which are advantageous for performance of the catalyst. It is also contemplated that precursors to the above mentioned materials can be used. For example, colloidal alumina sols, and

suspensions of any of above mentioned oxides can be used in the precursor, which are converted into the binder with subsequent processing.

[0088] A phosphorus-containing zeolite can be formed by contacting the zeolite with a phosphorus source to form a phosphorus containing precursor and heating (calcining) the phosphorus precursor to generate the phosphorus containing catalyst. The phosphorus source is in a form that provides intimate and/or high surface area contact with the zeolite catalyst. For example, the phosphorus source can be a solid that is co-mixed, e.g., milled, with the zeolite catalyst. In other embodiments, the phosphorus solution can be dissolved in a solvent to form a solution that can be applied to the zeolite, e.g., by immersion or spraying or other coating mechanism. For example, phosphorus can be introduced using the known method of incipient wetness technique. Incipient wetness impregnation (IW or IWI), also called capillary impregnation or dry impregnation, is a commonly used technique for the synthesis of heterogeneous catalysts. The phosphorus precursor is dissolved in an aqueous or organic solution and is then added to a catalyst support containing the same pore volume as the volume of the solution that was added. Capillary action draws the solution into the pores. Solution added in excess of the support pore volume causes the solution transport to change from a capillary action process to a diffusion process, which is much slower. The catalyst can then be dried and calcined to drive off the volatile components within the solution, depositing the phosphorus on the catalyst surface. The maximum loading is limited by the solubility of the precursor in the solution. The source of phosphorus can be any phosphorus containing solid or liquid; in certain embodiments, the phosphorus source is one or more of phosphoric acid, ortho phosphates, poly phosphates, ammonium phosphate, di-ammonium phosphates, mono, di and tri phenyl phosphates, organo phosphates, and sodium phosphates or any mixtures thereof. In some embodiments, the source of phosphorus is a salt of phosphoric acid or phosphoric acid itself of any combinations thereof. [0089] Nanozeolites (onto which the phosphorus can be absorbed or integrated) can be synthesized in an aqueous phase and the composition, temperature, crystallization time, aging time etc. are controlled to allow nanozeolites to form. The principle of the synthesis is derived from the nucleation and crystallization: facilitating the nucleation, which produces nuclei as much as possible; and controlling a subsequent slow growth of crystal particles. See, e.g., Chem. Mater., 2005, 77 (10), pp 2494-2513; Micropor. Mesopor. Matl 156 (2012), pp 97-105; Ceram. Intl, 30 (2013) pp 683-689; Micropor. Mesopor. Matl 156 (2012), pp 29- 35; J. Catal. 302 (2013), pp 15-125; Wan et al. Chemica 2013 Conference Proceedings, Brisbain, Australia, Sept. 20-Oct. 2, 2013, Paper No. 30454, for further details in preparation of nanozeolite, the contents of which are incorporated by reference. Alternatively, nanozeolites can be obtained from commercial sources, such as Advanced Chemical

Supplier, Medford, MA (http://www.acsmaterial.com/product.asp?cid=33&id=141)

[0090] According to one or more embodiments, the catalyst composition can be prepared using a sacrificial template method. A templating material is initially homogenously distributed in a continuous matrix of the heat stable phase (e.g., the zeolite and the non- zeolite binder materials) and is thereafter removed to result in a porous material. According to one or more embodiments, a zeolite catalyst composition is prepared by mixing a zeolite catalyst, an alumina-containing material, a sacrificial organic material having particle size and burn out properties selected to provide the desired mesopore and macropore size and pore distribution. The templating agents targets to form pores preferably greater than 500 A.

[0091] The step of introducing phosphorus to the zeolite catalyst can occur before during or after the formation of catalyst composition. In one or more embodiments, the phosphorus- containing zeolite is formed and the phosphorous-containing zeolite is combined with an alumina-containing material and a sacrificial organic material to form the catalyst

composition. In one or more embodiments, the zeolite is combined with an alumina- containing material and a sacrificial organic material to form the catalyst composition;

thereafter, the catalyst composition is exposed to a phosphorus source as described herein above to form a phosphorus precursor. The phosphorus precursor is heated to form the phosphorus catalyst. In still other embodiments, the phosphorus source, zeolite, alumina- containing material and a sacrificial organic material are combined together and processed, e.g., heated, to form the phosphorus-containing catalyst. [0092] Typical sacrificial organic materials include organic materials, such as dense or hollow polymer beads, or particles. Within this broad range of suitable materials, suitable materials include cellulose, starch, polyethylene, PTFE, latex, polyethylene glycol (PEG), polypropylene glycol, acicular carbons, carbon black, activated carbon, graphite, carboxylic acids such as oxalic acid, steric acid and/or their esters, and lingo-sulfonic acid and combinations thereof. The size, shape and arrangement of the sacrificial organic material offers significant versatility to independently tailor the porosity, pore size distribution and pore morphology. The organic compound is preferably selected based upon the nanozeolite material being used, so as to provide pore volume of appropriate size and shape. It should be appreciated that the amount of meso and macro pore-sized pore volume provided depends at least in part upon the amount of sacrificial organic material included in the precursor. In addition to the nanozeolite crystallite properties, the size of the meso and macro pore-sized pores depends at least in part on the particle or bead size of the sacrificial organic material. Thus, the amount and size of meso and macro pore-sized pore volume can be selectively controlled by selecting the proper amount and size of sacrificial organic material.

Exemplary particle size can range from about 1 μπι to 250 μπι, or preferably between about 5 μπι and 180 μπι. In other embodiments, the particle size can be much smaller, particularly when using carbon as the sacrificial material.

[0093] The phosphorus-containing zeolite catalyst, alumina-containing material and sacrificial organic material are combined to obtain a paste of a consistency suitable for further post-processing, such as molding or extruding. Also, the binder materials may be provided in part in colloidal form so as to facilitate extrusion of the bound components. The mixture may also be combined with other materials, used as diluents or glidants or rheology control agents, to assist in the powder processing. It may be advantageous to precombine the powder ingredients. The combined powder ingredients can be sieved to reduce agglomeration and provide a uniform particle size.

[0094] The resulting paste can be formed into a desired shape and then heated to form the crystalline composition and burn out the sacrificial organic material, thereby introduce macroporosity and/or mesoporosity into the composition. Calcine temperatures are preferably kept below a temperature known to degrade or modify the catalytic properties of the zeolite. In exemplary embodiments, the precursor is heated to temperatures in the range of 300-700 °C, and preferably in the range of 500-600°C. The solidified crystalline microporous zeolite composition contains a meso and macro pore-sized pore volume having the desired narrow pore-sized distribution.

[0095] The phosphorous-containing zeolite can also be made by impregnating a solution containing phosphorous on to the formed zeolite catalyst which is in the form of an extrudate or a pellet along with the non-zeolite binder. The zeolite in the formed extrudate can be a nano-zeolite. Any source of phosphorous can be used. If the phosphorous source is solid, it is dissolved in a suitable liquid, preferably water. The solution is made equal to the pore volume of the formed zeolite extrudate. If the phosphorous source is a liquid, a known quantity is taken and diluted, preferably with water, such that the volume of total liquid is equal to the pore volume of the formed zeolite extrudate. This solution is sprayed on to the formed zeolite extrudates, dried and calcined to obtain the phosphorous modified zeolite extrudate. The zeolite can be nano-zeolite.

Biomass to Biofuel Conversion

[0096] The catalyst composition prepared in accordance with the invention is particularly useful as a catalyst for the generation of renewable liquid fuels, e.g., "biofuels," from biomass. In one or more embodiments, it can be used for the production of desired aromatics such as benzene, toluene, and xylene (BTX) and other substituted aromatic fuels from pyrolysis gases. Conversion of biovapors to fuel or fuel components of diesel or jet fuel is also contemplated. It has been surprisingly determined that pyrolysis vapors derived at relatively low pyrolysis temperatures, e.g., less than 400°C, or less than 350°C, when separated from the pyrolysis reactor and directed, without condensation, over a heated catalyst bed including a phosphorus-containing nanozeolite provides high fuel yields (e.g., greater than 6.5%, or greater than 7.0% or greater than 7.5%, or greater than 8.0%> or greater than 8.5%) by weight of input biomass, or in the range of 6.5-12%) by weight of input biomass) with very low coking. In one or more embodiments, coking is less than 5 wt%>, or less than 4 wt%>, or less than 3 wt%> or even less than 2 wt%> by weight of input biomass or in the range of 1-5 wt%> or any range bounded by any of the values noted herein above.

[0097] Biovapors containing oxygenated feedstocks rich in C5 and C6 sugars can be generated from biomass using a number of conventional processes, such as chemical, thermal and biological decomposition processes. Exemplary chemical processes include acid hydrolysis of cellulosic materials. There are at least two ways to hydrolyze cellulose: chemically and enzymatically. The chemical method uses acids to hydrolyze cellulose under high temperature and pressure. The enzymatic method uses bacteria secreted proteins to hydrolyze cellulose, namely cellulase.

[0098] Thermal processes can include pyrolysis. The process of heating a combustible material in either a reduced oxygen environment or oxygen-free environment is called pyrolysis. Pyrolyzing wood and other forms of mixed biomass produces a high carbon content coke (also called biochar) and a complex mixture of decomposition products.

Depending on the conditions of the pyrolysis, the composition of the products can be varied. In general, when subject to high temperatures (e.g., 800°C) for prolonged periods of time, pyrolysis ultimately yields syngas. At lower temperatures and time intervals, increasingly complex hydrocarbons and oxygenated hydrocarbons are present in the gas stream from the pyrolyzed biomass. The composition of pyrolysis gases can be complex and typically includes a range of oxygenated organic molecules, many having a size and/or molecular weight that is larger than conventional feedstocks such as methanol, ethanol and dimethyl ether (DME).

[0099] The biomass used herein can be any biomass capable of being converted to liquid and gaseous hydrocarbons when subjected to pyrolysis. As used herein, the term 'biomass' includes any material derived or readily obtained from plant or animal sources. Such material can include without limitation: (i) plant products such as bark, leaves, tree branches, tree stumps, hardwood chips, softwood chips, grape pumice, sugarcane bagasse, palm derived empty fruit bunches, switchgrass; and (ii) pellet material such as grass, wood and hay pellets, crop products such as corn, wheat and kenaf. This term may also include seeds such as vegetable seeds, sunflower seeds, fruit seeds, and legume seeds. The term 'biomass' can also include: (i) waste products including animal manure such as poultry derived waste; (ii) commercial or recycled material including plastic, paper, paper pulp, cardboard, sawdust, timber residue, wood shavings and cloth; (iii) municipal waste including sewage waste; (iv) agricultural waste such as coconut shells, pecan shells, almond shells, coffee grounds; and (v) agricultural feed products such as rice straw, wheat straw, rice hulls, corn stover, corn straw, and corn cobs.

[0100] Conventional methods for pyrolyzing carbon-containing material may be used in the multistage method and system described herein. A number of well-known pyrolysis reactors, including fixed bed reactors, fluidized bed reactors, circulating bed reactors, bubbling fluid bed reactors, vacuum moving bed reactors, entrained flow reactors, cyclonic or vortex reactors, rotating cone reactors, auger reactors, ablative reactors, microwave or plasma assisted pyrolysis reactors, and vacuum moving bed reactors can be employed for the pyrolysis process. A biomass fractionator, such as that described in US 8,216,430, assigned to Cool Planet Energy Systems, Inc., which details the placement of biomass in thin sheets in compartments and subjects the biomass to controllable pyrolysis conditions, also may be used. Auger pyrolyzers and pyrolysis methods can also be used, such as those described in United States Publication 2014/0183022, published July 3, 2014, which is incorporated herein by reference. In some embodiments, pyrolysis is conducted at temperatures in the range of 250°C-500°% or preferably in the range of 350°C-425°C to produce a mixture of oxygenated hydrocarbon vapors, collectively referred to as pyrolysis vapors. Biomass is typically comprised of a wide array of compounds classified within the categories of cellulose, hemicelluloses, lignin, starches, and lipids. These compounds go through multiple steps of decomposition when subject to the pyrolysis process. For example, hemicelluloses comprise C5 sugars such as fructose and xylose, which yield furfural and

hydroxymethylfurfurals upon thermolysis. The latter compounds can be further converted to fuel intermediates furan and tetrahydrofuran.

[0101] The pyrolysis vapors generated from the thermal degradation of biomass are directed to one or more catalytic reactor(s) for conversion to biofuel. In one or more embodiments, biomass pyrolysis vapors are converted to gasoline, diesel and/or jet fuel or fuel components by passing the pyrolysis vapors over a catalyst composition as described herein that has been heated to a temperature in the range of 350°C-500°C at a weight hourly space velocity (weight of vapor feed per unit weight catalyst/hour) of 0.1-10 hr "1 .

[0102] In some embodiments, water or steam optionally is injected during pyrolysis and the combination of biovapors and steam or water is passed over the zeolite catalyst composition bed. In some embodiments, the water source can be process water collected as a byproduct of the conversion of biovapors into gasoline, diesel and jet range hydrocarbons. The ratio of steam to biomass can be in the range of 0.05 to 0.9 (wt/wt). Addition of water or steam to the catalyst process has been observed to increase fuel yield and/or reduce coking. In one or more embodiments, the fuel yield increases by up to 5% or by up to 10 % or by up to 15% or by up to 20% as compared to a comparable process run in the absence of steam. In one or more embodiments, coke formation decreases by up to 5% or by up to 10 % or by up to 15% or by up to 20% as compared to a comparable process run in the absence of steam. Without being bound by any theory of operation, the steam may serve to clean the catalyst and remove coke as it forms, thereby maintaining the active surface area of the catalyst for longer periods of time and increasing total fuel yields for the lifetime of the catalyst.

[0103] The catalyst composition is housed in a catalytic reactor and can be a fixed bed reactor. In one or more embodiments, the zeolite reactor includes multiple reactors in series. When multiple reactors are used, they can be operated at the same temperature or at different temperatures. When multiple catalytic reactors are used, the effluent from the first reactor can be passed to the second reactor without intermediate processing. In some embodiments, the first and second catalysts can be contained within the same reactor, positioned so that the flowing vapors interact sequentially with the first and second catalyst compositions. In other embodiments, the effluent from each reactor is condensed, with liquid product being separated and the non-condensable gaseous product being introduced in to the subsequent catalytic reactor for further fuel production.

[0104] In one or more embodiments, the catalytic process includes at least two catalyst beds. In one or more embodiments, a first catalyst bed includes a 'guard' catalyst that includes the phosphorus-containing zeolite catalyst described herein, and a second catalyst bed includes a BTX catalyst, e.g., a nanozeolite catalyst, with or without phosphorus.

Exemplary nanozeolite catalysts suitable for use in the second catalyst bed as a BTX catalyst are described in co-pending United States Patent Application No. 62/191166 filed on July 10, 2015. It has been surprisingly determined that use of a phosphorus-containing zeolite catalyst is particularly effective in reducing coking in the first of the two-serially linked catalyst beds, that is, the "guard catalyst."

[0105] A process for converting biomass vapors to gasoline, diesel and jet range hydrocarbons includes advantageously first passing the biovapors generated from pyrolysis of biomass through a guard catalyst including the phosphorus-containing zeolite catalyst described herein under one set of temperature and pressure conditions and then directing the vapors to a second catalyst bed including a nanozeolite catalyst at either the same or different temperature and pressure conditions. The guard catalyst is a catalyst composition as described herein containing a phosphorus-containing zeolite or nanozeolite catalyst. In one or more embodiments, the nanozeolite catalyst used in the second catalyst bed is selected from the nanozeolite catalysts described in co-pending United States Patent Application No. 62/191166 filed on July 10, 2015. In one or more embodiments, the nanozeolite catalyst used in the second catalyst bed comprises a ZSM-5 nanozeolite. In one or more embodiments, the both the first and second catalyst beds includes a phosphorus-containing zeolite catalyst composition as described herein; however, the specific zeolite catalyst composition used in each catalyst bed can be the same or different.

[0106] The guard catalyst also can include additional catalysts. Exemplary additional catalyst include a dehydration catalyst, decarboxylation catalyst, decarbonylation catalyst, deoxygenation catalyst or other catalyst that can reduce the oxygen content and increase the hydrogen content of the biovapor. Biomass decomposition, such as by pyrolysis at temperatures below 400 °C, typically produces oxygenated feedstocks (primarily sugars and sugar-alcohols). The guard catalyst can reduce the hydrogen and oxygen content of the feedstock, for example by removal of water, formaldehyde and carbon dioxide, to provide furans and other olefinic compounds. Use of a guard catalyst to increase the quality of the biovapor stream entering the nanozeolite catalyst train can improve fuel yield and reduce coking on the nanozeolite catalyst.

[0107] The catalyst beds can be run under different conditions, e.g., at different temperatures. For example, the first catalyst bed can be operated at a temperature in the range of 250-400°C and the second catalyst bed can be operated at a temperature in the range of 300-500°C. In one or more embodiments, the temperature of the second catalyst bed in greater than that of the first catalyst bed. The lower temperature is not as efficient at converting the pyrolysis gases into fuel grade molecules, however, it can begin the conversion of the oxygenates to simpler molecules, such as furans and olefins. The second bed is run at a higher temperature that is capable of forming the fuel molecules. Because the reactant mix has been simplified by reaction the first bed, conversion to fuel grade molecules is more efficient and the dwell time can be reduced. This reduces the changes of coking at the higher temperatures of the second bed.

[0108] In operation, a raw biovapor obtained, for example, as a heated gas directly from a pyrolysis reactor is fed, optionally without condensation, into a catalyst reactor having a guard catalyst and a BTX catalyst. The catalysis reactor is arranged for sequential contact with first guard catalyst and then the BTX catalyst. The run can be continuous as long as the fuel output remain within acceptable parameters. The quality of the fuel output is monitored in terms of fuel yield, fuel oxygen content and/or coke levels. Thus, fuel levels should remain above a threshold level, while fuel oxygen content and coke should remain below threshold levels during operation. After the catalyst is spent, it can be regenerated.

[0109] The invention is illustrated with reference to the following examples, which are presented for the purpose of illustration only and are not intended to limit the extent of the invention, the scope of which is found in the claims that follow.

1. Biomass Feedstock

[0110] Pine pellets were used as biomass feedstock. They were purchased from

Okanagan Pellet Company (BC, Canada) and used as received. The elemental composition, moisture content, and ash content of the pine pellets were analyzed by Wyoming Analytical Laboratories, Inc. using well known ASTM methods. The carbon, hydrogen, and oxygen contents are 46.53 wt.%, 4.97 wt.%, and 42.41 wt.%, respectively. The moisture content and ash content are 5.60 wt.% and 0.26 wt.%, respectively. Other suitable biomass includes Lobloly pine pellets which have carbon and hydrogen contents around 5.2 wt% and 6.6 wt% respectively.

2. Catalyst Preparation

[0111] A 3 wt.%) phosphoric acid modified nanozeolite catalysts (i.e., the weight ratio of phosphorous to nanozeolite) were prepared in the laboratory via incipient wetness impregnation technique. Specifically, 34.51 g of 85 wt.% aqueous H 3 PO 4 solution was slowly added into 114.82 g of stirred H 2 0. Following this step, the diluted H 3 PO 4 solution was sprayed onto 300 g of nanozeolite catalysts in a rotating bucket. This allowed even distribution of the liquid throughout the catalyst extrudates. The catalyst extrudates were Ι/δ" 1 inch diameter and ½ inch in length approximately. Subsequently, the nanozeolite catalyst extrudates were dried in oven at 120°C for 4 h and then calcined at 550°C for 8 h. The phosphoric acid modified nanozeolite and fresh nanozeolite are labeled as P-BTX and BTX, respectively.

3. Catalyst Testing

[0112] The experiments were performed in laboratory unit abbreviated as VRS unit.

In short, the unit had a batch pyrolyzer which was mated to two catalytic reactors in series as shown in Figure 1. The first reactor was named as the guard reactor and operated at 325°C. The second reactor was named as the BTX reactor and operated at 370°C. N 2 was used as carrier gas in the experiments. Temperature and pressure in the pyrolysis reactor, guard reactor, and BTX reactor were computer-monitored through Lab View software. In a typical experiment, 450 g of pine pellets, 150 g of guard catalyst, and 150 g of BTX catalyst were charged into the pyrolysis reactor, guard reactor, and BTX reactor, respectively.

Experimental runs were conducted in which P-BTX and BTX catalysts were used in various combinations as shown in Table 1.

Table 1. Catalyst combinations for different experimental runs

Catalyst used in Reactors

Experiment #

Guard Reactor BTX Reactor

1 P-BTX BTX

2 BTX BTX

3 P-BTX P-BTX

[0113] The N 2 flow was set as 0.12 m /h and was used to carry the bio-vapors generated from the pyrolysis reactor to guard reactor and BTX reactor. The pyrolysis reactor was then heated to 150°C in 10 min and maintained at 150°C for 20 min while the guard reactor and BTX reactor were heated to 325°C and 370°C in 30 min, respectively. Subsequently, the temperature of the pyrolysis reactor was heated from 150°C to 365°C in 4 h and maintained at 365°C for 1 h. During the reaction, the gas sample were collected and analyzed every hour. Liquid samples were also pulled on an hourly basis. The light gases were recirculated to the front of the guard bed using a compressor as shown in the schematic in Figure 1. The entire VRS unit was run at a pressure of 7 to 8 psig. This pressure level was constantly monitored and controlled using a back-pressure regulator. The excess gas that was being vented out was also measured using a ritter meter (for mass balance purpose). After the predetermined reaction time, the unit was cooled down to room temperature. The whole operation took approximately 8 hours. On the next day, only the char was removed from the pyrolysis reactor and 450 g of pine pellets was reloaded to continue the experiment. After all char was removed, it was collected weighed (for mass balance measurements) and stored. The hourly liquid samples collected during the course of the experiment were mixed together to obtain a total measure of liquids (raw fuel and process water) collected from the entire experiment. Following the same procedure, the reaction was carried out under the same reaction conditions for seven consecutive days.

[0114] The gas samples for every experimental day were collected in gas bags were analyzed using a gas chromatograph on the same day. The raw fuel and process water obtained for that day were separated using a separator funnel. The daily oxygen content (measured using an oxygen analyzer) of the raw fuel was measured on the total raw fuel obtained in that particular experimental day. Later, the raw fuel from seven consecutive days was collected and was subject for further analysis. The raw fuel was distilled using laboratory distillation apparatus at atmospheric pressure from room temperature to 430F to get the reformate distillate cut. After obtaining the reformate distillate cut, the distillation unit was subject to vacuum pressure so that the resulting temperature is from 43 OF to 600F. This cut was labeled as diesel cut. The remaining fuel in the distillation pot was labeled as heavy distillate (aka bunker fuel). PIONA analysis and GC-MS analysis were performed on the raw fuel and reformate distillate cuts.

4. Results and Discussion

[0115] The P-BTX was tested as guard catalyst followed by BTX as BTX catalyst.

For comparison, the reaction with BTX as guard catalyst was also conducted at otherwise similar conditions. As shown in Figures 1 and 2, the daily fuel yield is very similar, while the daily oxygen content in the fuel with P- BTX as guard catalyst is lower compared to that with BTX as guard catalyst. The mass balance as well as average product yields (i.e., from Day-1 to Day-5) such as fuel, char, light gas, process water, and coke are summarized in Table 2.

Table 2. Comparison of P-BTX and BTX as guard catalysts

Experiment #

Product Yield (wt.%)

1 (P-BTX BTX) 2 (BTX BTX)

BTX)

Fuel 7.11 7.38 7.25 Char 38.75 38.72 38.77

Light Gas 19.62 17.59 18.06

Process Water 31.56 30.50 31.61

Coke 1.47 1.89 1.34

Mass Balance 98.5 95.79 97.02

[0116] In all the runs, the mass balance was observed to be >95%. Experiment 1 (P- BTX/BTX) and Experiment 3 (P-BTX/P-BTX) display slightly lower fuel yield (within experimental error for all practical purposes) while the char yield, light gas yield, and process water yield are very similar. The coke weights for the various experiments are compared in Figure 3, in which coking on the guard reactor and the BTX reactor are reported separately. The coke weight on the guard catalyst is significantly lower when the guard catalyst is P- BTX, as compared to BTX as guard catalyst. In contrast, the coke weight on BTX as BTX catalyst remains relatively unchanged. Further improvement (reduction) in coking on the BTX catalyst is observed when both the guard catalyst and the BTX catalyst are P-BTX. A lower coke weight on the catalyst and a fuel containing lower levels of oxygen content is advantageous as it increases run time between catalyst regeneration cycles. Thus, P- BTX catalyst generates very similar raw fuel yields compared to BTX, however the P- BTX catalyst also results in low coke yields and low fuel oxygen levels.

[0117] Figure 5 shows the reformate yields for the 3 catalyst systems. The raw fuel obtained for the first 5 days of experiments for each catalyst system was collected and distilled using a commonly available atmospheric laboratory distillation apparatus. The distillation was conducted from room temperature to 430F for all the 3 catalyst systems. Figure 5 indicates that the distillate reformate yield was similar for all 3 catalyst system, indicating that the phosphorous modification does not change the reformate yields. Figure 6 shows the oxygen content of the reformate yields. Figure 6 also indicates that the oxygen content for the 3 catalyst systems is more or less the same (within experimental error) indicating that phosphorus modification does not change the product distribution of oxygenates significantly. Since we have noticed that the raw fuel oxygen levels are lower using phosphorous modified catalysts, it is likely that the phosphorous modification is resulting in lower levels of oxygen in fuel with boiling point greater than 430F.

[0118] Unless otherwise defined, used or characterized herein, terms that are used herein (including technical and scientific terms) are to be interpreted as having a meaning that is consistent with their accepted meaning in the context of the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein. For example, if a particular composition is referenced, the composition may be substantially, though not perfectly pure, as practical and imperfect realities may apply; e.g., the potential presence of at least trace impurities (e.g., at less than 1 or 2%) can be understood as being within the scope of the description; likewise, if a particular shape is referenced, the shape is intended to include imperfect variations from ideal shapes, e.g., due to manufacturing tolerances. Percentages or concentrations expressed herein can represent either by weight or by volume.

[0119] Although the terms, first, second, third, etc., may be used herein to describe various elements, these elements are not to be limited by these terms. These terms are simply used to distinguish one element from another. Thus, a first element, discussed below, could be termed a second element without departing from the teachings of the exemplary embodiments. Spatially relative terms, such as "above," "below," "left," "right," "in front," "behind," and the like, may be used herein for ease of description to describe the relationship of one element to another element, as illustrated in the figures. It will be understood that the spatially relative terms, as well as the illustrated configurations, are intended to encompass different orientations of the apparatus in use or operation in addition to the orientations described herein and depicted in the figures. For example, if the apparatus in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term, "above," may encompass both an orientation of above and below. The apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Further still, in this disclosure, when an element is referred to as being "on," "connected to," "coupled to," "in contact with," etc., another element, it may be directly on, connected to, coupled to, or in contact with the other element or intervening elements may be present unless otherwise specified. The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of exemplary embodiments. As used herein, singular forms, such as "a" and "an," are intended to include the plural forms as well, unless the context indicates otherwise.

[0120] It will be appreciated that while a particular sequence of steps has been shown and described for purposes of explanation, the sequence may be varied in certain respects, or the steps may be combined, while still obtaining the desired configuration. Additionally, modifications to the disclosed embodiment and the invention as claimed are possible and within the scope of this disclosed invention.

[0121] It will also be appreciated that embodiments can be variously combined or separated without parting from the invention.