Patent Application
20250215326
The field is the process of producing jet fuel. The field may particularly relate to the production of jet fuel using biomass.
Biomass refining or biorefining is becoming more prevalent in industry. Cellulose fibers and sugars, hemicellulose sugars, lignin, syngas, and derivatives of these intermediates are being used by many stakeholders for chemical and fuel production. They are capable of processing incoming biomass much the same as petroleum refineries now process crude oil. Underutilized lignocellulosic biomass feedstocks have the potential to be much cheaper than petroleum, on a carbon basis, as well as much better from an environmental life-cycle standpoint.
Lignocellulosic biomass is the most abundant renewable material on the planet. The lignocellulosic biomass is a potential feedstock for producing chemicals, fuels, and materials. Lignocellulosic biomass normally comprises primarily cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are natural polymers of sugars, and lignin is an aromatic/aliphatic hydrocarbon polymer reinforcing the entire biomass network. Some forms of biomass (e.g., recycled materials) do not contain hemicellulose.
It is beneficial to process biomass in a way that effectively separates the major fractions (cellulose, hemicellulose, and lignin) from each other. Cellulose from biomass can be used in industrial cellulose applications directly, such as to make paper or other pulp-derived products. The cellulose can also be subjected to further processing to either modify the cellulose in some way or convert it into glucose. Hemicellulose sugars can be fermented to a variety of products, such as ethanol, or converted to other chemicals. Lignin from biomass has value as a solid fuel and also as an energy feedstock to produce liquid fuels, synthesis gas, or hydrogen; and as an intermediate to make a variety of polymeric compounds. Additionally, minor components such as proteins or rare sugars can be extracted and purified for specialty applications.
Great importance has been attached to renewable energy resources all over the world. Biomass derived ethanol fuel is becoming a member of the technical field of liquid fuel, and the processes of producing ethanol fuel from starch and cellulose are under modification and improvement.
The use of lignocellulosic biomass as a source of renewable raw material is a leading area for the replacement of petroleum products.
Bioethanol can be produced by fermentation of biological feedstock. Fermentation produces substantial carbon dioxide which must be managed. The bioethanol is then dehydrated to produce ethylene.
Ethylene can be dimerized into olefins such as C4, C6 and C8 olefins. Olefin oligomerization is a process that can oligomerize smaller olefins into larger olefins. More specifically, it can convert olefins into distillates including jet fuel and diesel range products. The olefinic oligomerized distillate can be hydrogenated for use as transportation fuel.
An ethanol to jet fuel process is one of the routes that holds promise to minimize or eliminate net carbon combustion. The end product of this process is jet and diesel fuel produced out of bioethanol. Jet fuel is a sustainable aviation fuel intended to replace jet fuel produced out of conventional sources such as crude oil.
Jet fuel is one of the few petroleum fuels that cannot be replaced easily by electrical motor systems because a high energy output is required to fuel planes which cannot be supplied with electric motors. Large incentives are currently available for green jet fuel in certain regions to reduce the environmental impact of fossil-derived jet fuels.
Currently, a limited supply of lignin is available as a by-product of the pulp and paper industry. However, in the near future, large quantities of lignin residue material will be available from biomass-to-ethanol processes and other biorefineries and associated processes. So far, in typical biorefinery process designs, lignin appears as a residual material with limited opportunities for its utilization. Other sources of lignin material can include agricultural products and wastes, municipal wastes, and the like.
Low carbon intensive sustainable aviation fuels are the need of the hour to reduce aviation greenhouse gas emissions. It would also help to minimize dependence on fossil fuels and volumetrically enhance the drop in aviation fuel share by the biomass derived jet fuels. Furthermore, existing routes to produce SAF are cost intensive and feedstock limited.
Upgrading of the lignin residue by a catalytic conversion process to high-value fuels and fuel additives have been sought to enhance the competitiveness of biorefinery technologies. There is a need for a process for conversion of lignin to more valuable products that are economically viable, and useful to produce fuels such as motor fuel.
The present disclosure provides a process of producing jet fuel. The process of producing jet fuel addresses the growing sustainable aviation fuel (SAF) economy by providing a novel process for SAF production at a lower cost compared to existing processes. The process can produce low-carbon jet fuel from an aromatic rich stream. The process reduces the cost of producing jet fuel and provides a higher distillate yield.
The term “communication” means that fluid flow is operatively permitted between enumerated components, which may be characterized as “fluid communication”.
The term “downstream communication” means that at least a portion of fluid flowing to the subject in downstream communication may operatively flow from the object with which it fluidly communicates.
The term “upstream communication” means that at least a portion of the fluid flowing from the subject in upstream communication may operatively flow to the object with which it fluidly communicates.
The term “direct communication” means that fluid flow from the upstream component enters the downstream component without passing through any other intervening vessel.
The term “indirect communication” means that fluid flow from the upstream component enters the downstream component after passing through an intervening vessel.
The term “bypass” means that the object is out of downstream communication with a bypassing subject at least to the extent of bypassing.
As used herein, the term “predominant” or “predominate” means greater than 50%, suitably greater than 75% and preferably greater than 90%.
The term “column” means a distillation column or columns for separating one or more components of different volatilities. Unless otherwise indicated, each column includes a condenser on an overhead of the column to condense and reflux a portion of an overhead stream back to the top of the column and a reboiler at a bottom of the column to vaporize and send a portion of a bottoms stream back to the bottom of the column. Feeds to the columns may be preheated. The top pressure is the pressure of the overhead vapor at the vapor outlet of the column. The bottom temperature is the liquid bottom outlet temperature. Overhead lines and bottoms lines refer to the net lines from the column downstream of any reflux or reboil to the column. Stripper columns may omit a reboiler at a bottom of the column and instead provide heating requirements and separation impetus from a fluidized inert media such as steam. Stripping columns typically feed a top tray and take main product from the bottom.
As used herein, the term “separator” means a vessel which has an inlet and at least an overhead vapor outlet and a bottoms liquid outlet and may also have an aqueous stream outlet from a boot. A flash drum is a type of separator which may be in downstream communication with a separator that may be operated at higher pressure. As used herein, the term “boiling point temperature” means atmospheric equivalent boiling point (AEBP) as calculated from the observed boiling temperature and the distillation pressure, as calculated using the equations furnished in ASTM D1160 appendix A7 entitled “Practice for Converting Observed Vapor Temperatures to Atmospheric Equivalent Temperatures”.
As used herein, the term “True Boiling Point” (TBP) means a test method for determining the boiling point of a material which corresponds to ASTM D-2892 for the production of a liquefied gas, distillate fractions, and residuum of standardized quality on which analytical data can be obtained, and the determination of yields of the above fractions by both mass and volume from which a graph of temperature versus mass % distilled is produced using fifteen theoretical plates in a column with a 5:1 reflux ratio.
As used herein, the term “T5”, “T90” or “T95” means the temperature at which 5 mass percent, 90 mass percent or 95 mass percent, as the case may be, respectively, of the sample boils using ASTM D-86 or TBP.
As used herein, the term “initial boiling point” (IBP) means the temperature at which the sample begins to boil using ASTM D-7169, ASTM D-86 or TBP, as the case may be.
As used herein, the term “end point” (EP) means the temperature at which the sample has all boiled off using ASTM D-7169, ASTM D-86 or TBP, as the case may be.
As used herein, the term “diesel” means hydrocarbons boiling in the range of an IBP between about 125° C. (257° F.) and about 175° C. (347° F.) or a T5 between about 150° C. (302° F.) and about 200° C. (392° F.) and the “diesel cut point” comprising a T95 between about 343° C. (650° F.) and about 399° C. (750° F.) using the TBP distillation method or a T90 between 280° C. (536° F.) and about 340° C. (644° F.) using ASTM D-86. The term “green diesel” means diesel comprising hydrocarbons not sourced from fossil fuels.
As used herein, the term “jet fuel” means hydrocarbons boiling in the range of a T10 between about 190° C. (374° F.) and about 215° C. (419° F.) and an end point of between about 290° C. (554° F.) and about 310° C. (590° F.). The term “green jet fuel” means jet fuel comprising hydrocarbons not sourced from fossil fuels.
“Biofuel,” as defined herein, is a fuel product at least partly derived from “biomass,” the latter being a renewable resource of biological origin.
“Lignin,” as defined herein, is a complex chemical compound most commonly derived from wood and generally being an integral part of the secondary cell walls of plants.
“Cellulose,” as defined herein, is essentially a glucose polymer by virtue of it being a linear polysaccharide comprised of from hundreds to thousands of D-glucose monomeric units linked via glycosidic bonds.
“Hemicellulose,” as defined herein, can be any of several heteropolysaccharides present in almost all plant cell walls along with cellulose. In contrast to cellulose, hemicellulose is commonly branched, typically shorter in length/molecular weight (a few hundred to a few thousand saccharide units), and contains many different sugar monomers such as, but not limited to, glucose, xylose, mannose, galactose, rhamnose, and arabinose.
The term, “lignocellulosic,” as defined herein, refers to plant biomass that is composed of cellulose, hemicellulose, and lignin.
A “Generation 2 (Gen 2) biofuel,” as defined herein, is any biofuel whose production is independent of the food chain.
Cellulosic biomass, which is used as the starting material according to the present disclosure may be defined as biomass containing cellulose. Here, biomass refers to substances having their edible parts removed but still rich in biomass energy, such as crop straw, bamboo, reed, trees, leaves, weeds and hydrophytes, etc. The main constituents of such cellulosic biomass may include polysaccharide celluloses, hemicelluloses, and lignin of polyaromatic compounds.
Lignocellulosic biomass is essentially a source of carbohydrates. It is composed of three main constituents: cellulose, hemicellulose, and lignin. Hemicellulose is a polysaccharide essentially consisting of pentoses and hexoses. Lignin is a macromolecule of complex structure and high molecular weight, composed of aromatic alcohols connected by ether bonds. The three basic building blocks of lignin, p-coumaryl alcohol, coniferyl alcohol, and sinapyl alcohol, are synthesized via the phenylpropanoid pathway in plants and differ in their extent of methoxylation (0, 1, and 2, respectively). Lignin is synthesized via enzymatic dehydrogenation of these monomers, which form both C—O and C—C bonds, leading to a heterogeneous structure and a three-dimensional structure.
Cellulose and lignin represent two of the most prominent renewable carbon sources. Lignin, a second to cellulose as the most plentiful renewable carbon source on earth, is an amorphous three-dimensional energy-rich phenolic biopolymer, which is deposited in all vascular plants and provides rigidity and strength to their cell walls. The lignin polymeric structure is composed primarily of three phenylpropanoid building units: p-hydroxyphenylpropane, guaiacylpropane, and syringylpropane interconnected by etheric and carbon-to-carbon linkages. Generally, in unprocessed lignin, two thirds or more of these linkages are ether bonds, while the remaining linkages are carbon-carbon bonds.
Different types of lignin differ significantly in the ratio between these monomers. Inherent in its molecular nature, the lignin bio-mass component can potentially be converted directly to liquid fuels, for example high-octane alkylbenzene, aromatic ether gasoline-blending components, and/or naphthenic kerosene fuels (NK).
The present disclosure is related to a method for processing a lignocellulosic biomass. The method included processing the biomass to separate lignin. The lignin is further processed to produce an aromatic rich bio-oil which can be converted into useable products such as biofuel. The process of the present disclosure comprises pyrolyzing the lignin to cleave-off some of the alkyl groups from the lignin structure and/or deoxygenating the lignin to provide aromatic molecules. Further processing of the lignin is also disclosed to produce the biofuel.
Turning to
In an exemplary embodiment, the lignocellulosic biomass may be subjected to a chemical pre-treatment step in the biomass processing unit 110. Some “pretreatment” of the biomass may be carried out prior to attempting the enzymatic hydrolysis of the cellulose and hemicellulose in the biomass. Pretreatment refers to a process that converts lignocellulosic biomass from its native form, in which it is resistant to cellulase enzyme systems, into a form for which cellulose hydrolysis is effective. Compared to untreated biomass, effectively pretreated lignocellulosic materials may be characterized by an increased surface area (porosity) accessible to cellulase enzymes, and solubilization or redistribution of lignin. Increased porosity results mainly from a combination of disruption of cellulose crystallinity, hemicellulose disruption/solubilization, and lignin redistribution and/or solubilization. The relative effectiveness in accomplishing at least some of these factors differs greatly among different existing pretreatment processes.
The purpose of the pretreatment is to significantly disrupt the structure of biomass in order to: (a) reduce the crystallinity of cellulose, (b) increase accessibility/susceptibility of cellulose and hemicellulose chains to enzymes/catalysts by increasing the surface area/porosity and (c) remove lignin. Thermo-chemical biomass pretreatments techniques may be used for improving the digestibility of this highly recalcitrant biomass. These pretreatments may include dilute acid contact, steam explosion, hydrothermal pyrolysis, dissolution in organic solvents in an aqueous medium, ammonia fiber explosion, contact with strong alkali using a base such as ammonia, sodium hydroxid or lime), and highly concentrated phosphoric acid contact.
In lime pretreatment, the biomass is pretreated with calcium hydroxide and water under different conditions of temperature and pressure. It can be conducted via (i) short-term pretreatment that lasts up to 6 hours, requiring temperatures of about 100° C. to about 160° C.
In some embodiments, the lignocellulosic biomass may be mixed with an ionic liquid for a sufficient time and temperature to swell the lignocellulosic biomass without dissolving the lignocellulosic biomass in the ionic liquid, and treating the swelled lignocellulosic biomass under mild alkaline treatment to separate the lignin from the cellulose and hemicellulose.
After pretreatment, the separated lignin may be subjected to a high-temperature hydrolysis so as to reduce oxygen content of the lignin and provide a lignin rich stream. By reducing the oxygen content of the lignin, the lignin becomes more amenable to hydroprocessing because, for example, less hydrogen is needed. Following hydrolysis, the processed lignin can be hydroprocessed to form usable products such as biofuel. In an exemplary embodiment, the hydrolysis of the lignin may be carried out at a temperature of about 220° C. to about 300° C. The lignin-rich stream obtained after the hydrolysis step may have an oxygen content of not more than 25 weight percent on an ash-free basis.
In another embodiment, lignin may be separated from the biomass by chemical delignification by separating the lignin from the cellulose.
The lignin-rich stream may be fermented to produce alcohol which can be separated from the lignin in line 112. An exemplary embodiment of the biomass processing unit 110 and the related steps is disclosed in
Any renewable material that can provide saccharides may be used as a feed 102 for the process 101 including the biomass processing unit 110 in
The corn flour is conveyed from the bin 22 to a slurry tank 24 in which it is mixed with an enzyme such as alpha amylase from line 25 and aqueous lime from line 26. Alpha-amylase is an enzyme that catalyzes the hydrolysis of α-bonds of large, α-linked polysaccharides, such as starch and glycogen, yielding shorter chains thereof, dextrins, and maltose. The lime is added usually in the form of calcium hydroxide to disrupt the lignocellulosic matrix to make the substrate more accessible to the enzymes. The slurried mixture is conveyed after a short residence time such as 3 to 10 minutes and heated to about 70 to about 90° C. en route to a liquefaction tank 28.
The liquefaction tank 28 is heated by a steam jacket to maintain temperature of about 70 to about 90° C. Residence time is optimized to reduce formation of dextrin units which are not fermentable in yeast. The multistirred liquefaction tank retains the slurry from about 45 to about 75 minutes. The enzyme breaks the starch into soluble simpler starches, glucose and dextrose in a mash.
The mash is conveyed to one or more cooking kettles 30, 31 where heating continues by a steam jacket at a temperature of about 100 to about 120° C. while continually stirring. Sulfuric acid from line 32 may be added to the cooking kettles 30, 31 to break up and loosen any polymeric material such as lignin and cellulose. Residence time in the cooking kettles 30, 31 may be for about 10 to about 20 minutes to mitigate by-product formation of methanol and fusel oils. The cooked mash is cooled to between about 50 and about 70° C. and conveyed to the saccharification tanks 34, 35.
Enzyme such as glucoamylase is added to the saccharification tanks from line 36 to effect saccharification of the cooked mash at the reduced temperature under stirring to produce dextrin. Residence time in the saccharification tanks 34, 35 is about 1.5 to about 2.5 hours. Saccharified broth is cooled to about 30 to about 50° C. and conveyed to fermenters 38, 39.
Nutrients in line 40 and anti-foaming agent in line 41 are also added to the fermenter 38. Air in line 42 is added to the bottom of the fermenters 38, 39 to promote ethanol production. Carbon dioxide from line 44 may also be added to the fermenters 38, 39 to promote further agitation in the fermenters. Carbon dioxide is also generated in the fermenters 38, 39. Some of the carbon dioxide is recycled in line 44 to the fermenters while surplus carbon dioxide is taken in line 46.
A beer alcohol stream in line 43 from the fermenters 38, 39 may be fed to a fractionation column 50 to concentrate the alcohol in the overhead line 51. A portion or all of the alcohol in the overhead line 51 may be taken in line 112 of
Referring back to
In an exemplary embodiment, the first treatment unit 130 is a hydrotreating unit. In the first treatment unit 130, the lignin stream in line 114 may react with hydrogen to yield one or more hydroprocessed or hydrotreated products. Such a hydrotreating step may itself comprise multiple sub steps. In the first treatment unit 130, the lignin stream in line 114 may be contacted with a hydrotreating catalyst in a hydrogen environment. The hydrotreating catalyst may comprising an active metal or metal-alloy hydrotreating catalyst component that is operationally integrated with a refractory support material. In some embodiments, the active metal catalyst component may be selected from the group consisting of cobalt-molybdenum (Co—Mo) catalyst, nickel-molybdenum (Ni—Mo) catalyst, noble metal catalyst, and combinations thereof. In some embodiments, the refractory support material typically comprises a refractory oxide support such as, but not limited to, Al2O3, SiO2-Al2O3, and combinations thereof. In some embodiments, the hydrotreating step may use an alumina-supported nickel-molybdenum catalyst. A zeolite including SAPO catalyst can be used. The hydrotreating step may be carried out at a temperature from about 288° C. (550° F.) to about 427° C. (800° F.), preferably between about 349° C. (690° F.) and about 400° C. (752° F.) and a pressure of about 700 kPa (g) (100 psig) to about 21 MPa (g) (3000 psig). In some such embodiments, the hydroprocessing is carried out under a H2 partial pressure of between about 400 psig and about 2000 psig. In some or other such embodiments, the hydrotreating may be carried out under a H2 partial pressure of between about 3447 kPa (g) (500 psig) and about 10342 kPa (g) (1500 psig).
The hydrotreating catalyst in the hydrotreating unit may comprise one or more noble metals dispersed on a high surface area support. Non-limiting examples of noble metals include platinum and/or palladium dispersed on an alumina support such as gamma-alumina. Suitable hydrotreating catalysts may include BDO 200, BDO 300 or BDO 400 available from UOP LLC in Des Plaines, Illinois.
In the hydrotreating unit, the aromatic rich bio-oil stream is contacted with a hydrotreating catalyst in the presence of hydrogen at hydrotreating conditions. The hydrotreating catalyst catalyzes hydrodeoxygenation reactions, including hydrodecarboxylation and hydrodecarbonylation reactions, to remove oxygenate functional groups which may be converted to water and carbon oxides.
In another exemplary embodiment, the first treatment unit 130 is a pyrolysis unit. Pyrolysis is an effective method for converting lignin into high value-added chemicals and renewable synthetic fuels. In the treatment unit 130, the lignin stream in line 114 is passed to a pyrolysis reactor. The pyrolysis reactor is sealed and purged with an inert gas until the pyrolysis reactor is filled with the inert gas, and then the pyrolysis reactor is heated up to a predetermined temperature. The inert gas may be selected from nitrogen gas, helium gas, neon gas and argon gas. After the temperature of the pyrolysis reactor is stabilized, the lignin is pyrolyzed for a certain time. In accordance with the present disclosure, the lignin stream may be pyrolyzed at a temperature from about 300° C. to about 1200° C. or about 500° C. to about 700° C. and for a time of about 10 seconds to about 1 hour. The pyrolysis reactor may be operated at a pressure from about 100 kPa (ambient pressure) to about 1000 kPa. In an aspect, the pyrolysis reactor may be a fluidized bed type. At the end of the pyrolysis, the solid product derived from the lignin pyrolysis is collected and washed with an organic solvent to remove the adhered bio-oil. An aromatic rich bio-oil is separated from the lignin char.
After the first treatment step in 130, an aromatic rich bio-oil stream is taken from the first treatment unit 130 in line 132. The aromatic rich bio-oil stream in line 132 may comprise benzene, toluene, and xylene (BTX). In an embodiment, the aromatic rich bio-oil stream in line 132 may be a BTX rich stream. The aromatic rich bio-oil stream in line 132 may comprise oxygenates which need to be removed before converting it into the biofuel. The aromatic rich bio-oil stream in line 132 may be optionally passed to a second treatment unit 140. In accordance with the present disclosure, the second treatment unit 140 may be a pyrolysis unit. In an exemplary embodiment, the optional second treatment unit 140 is a hydrotreating unit downstream of the pyrolysis unit of the first treatment unit 130. The hydrotreating unit of the second treatment unit is as described for the hydrotreating unit previously. In an alternative exemplary embodiment, the second treatment unit 140 is a pyrolysis unit downstream of the hydrotreating unit of the first treatment unit 130.
The first treatment unit 130 and the second treatment unit 140 provide multiple steps of treatment for the lignin stream in line 114. When the first treatment unit 130 is a pyrolysis unit, the second treatment unit 140 will be a hydrotreating unit to provide the de-oxygenated bio-oil stream. When the first treatment unit 130 is a hydrotreating unit, the second treatment unit 140 will be a pyrolysis unit.
A de-oxygenated bio-oil stream is taken in line 142 from the optional second treatment unit 140. The de-oxygenated bio-oil stream in line 142 is passed to the alkylation unit 150. In accordance with the present disclosure, the de-oxygenated bio-oil stream in line 142 may be fractionated to produce an aromatic naphtha stream which may be passed to the alkylation unit 150. An alkylating agent is also passed to the alkylation unit 150. Alkylation involves transfer of an alkyl group from an alkylating agent to an aromatic substrate widely referred to as an electrophilic aromatic substitution reaction. In the alkylation unit 150, C6+ alkylaromatics are produced by catalytically reacting the de-oxygenated bio-oil stream with the alkylating agent in the presence of an alkylation catalyst at an alkylation temperature and alkylation pressure to produce a product stream comprising C6+ alkylaromatics. The alkylation reaction is conducted at a temperature where the thermodynamics are favorable. In an embodiment, the alkylation unit 150 may be operated at a temperature of about 50° C. to about 400° C. and a pressure of about 1000 kPa (10 bar) to 10000 kPa (100 bar). Weight hourly space velocity (WHSV) for the alkylation reactor may range from about 0.1 hr−1 to about 10 hr−1. When an alcohol is the alkylation agent, water is produced and removed from the alkylation unit 150.
In an aspect, the alkylation catalyst may comprise one or more from the group comprising sulfuric acid, hydrofluoric acid, aluminum chloride, boron trifluoride, solid phosphoric acid, chlorided alumina, acidic alumina, aluminum phosphate, silica-alumina phosphate, amorphous silica-alumina, aluminosilicate, aluminosilicate zeolite, zirconia, sulfated zirconia, tungstated zirconia, tungsten carbide, molybdenum carbide, titania, sulfated carbon, phosphated carbon, phosphated silica, phosphated alumina, acidic resin, heteropolyacid, inorganic acid, and a combination of any two or more of the foregoing.
In one embodiment, the alkylation catalyst comprises an aluminosilicate zeolite. In one version, the alkylation catalyst further comprises a modifier selected from the group consisting of Ga, In, Zn, Fe, Mo, Ag, Au, Ni, P, Sc, Y, Ta, a lanthanide, and a combination of any two or more of the foregoing. In another version, the alkylation catalyst further comprises a metal selected from the group consisting of Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, an alloy of any two or more of the foregoing, and a combination of any two or more of the foregoing.
In an embodiment, the alkylation catalyst may be selected from zeolite catalyst or ionic liquid catalyst. In an exemplary embodiment, the alkylation catalyst comprises a SAPO based catalyst.
In an exemplary embodiment, the alkylating agent is an alcohol. In an aspect, the alkylating agent may be an alcohol stream taken from the biomass processing unit 110. In another aspect, the alcohol stream 112 is passed to the alkylation unit 150 as the alkylating agent.
In accordance with the present disclosure, the alcohol in the alcohol stream 112 is ethanol.
In accordance with the present disclosure, the alkylating agent may comprise one or more alcohol selected from ethanol, iso-butanol, and propanol separated from the lignocellulosic biomass in line 102.
In accordance with the present disclosure, the alkylating agent may comprise a bio-derived alcohol.
In an alternate embodiment, the alkylating agent may comprise an alcohol stream produced from carbon dioxide using renewable energy.
The alcohol stream in line 112 may be combined with the de-oxygenated bio-oil stream in line 142 to provide a combined stream in line 144 which is passed to the alkylation unit 150. In another exemplary embodiment, the alkylating agent is an olefin stream. The olefin stream may comprise any olefinic stream having C2 to C5 olefins. In accordance with the present disclosure, the olefin stream may be taken from an methanol to olefins unit, a paraffin dehydrogenation unit, a steam cracking unit, or an alcohol dehydration unit. In an embodiment, the combined stream in line 144 may comprise a molar ratio of the alkylating agent in line 112 to the aromatic rich bio-oil in line 142 from about 0.1 to about 6, preferably from about 0.1 to about 4. In an exemplary embodiment, the combined stream in line 144 may comprise a molar ratio of the alkylating agent in line 112 to the BTX in line 142 from about 0.1 to about 6, preferably from about 0.1 to about 4.
An alkylated aromatic product stream comprising a liquid fuel is separated from the alkylation unit 150 in line 152. In accordance with the present disclosure, the alkylated aromatic product stream in line 152 can be used as a biofuel or a motor biofuel.
In an embodiment, a portion of the alkylated aromatic product stream may be taken in a recycle in line 154. The recycle stream in line 154 may be recycled back to the alkylation unit 150. In an exemplary, the recycle stream in line 154 may be recycled to the alkylation unit 150 at a combined feed ratio (CFR) of about 1 to about 5. The “combined feed ratio” (or CFR) may be defined as a ratio corresponding to (mass flow rate of the combined stream in line 144+ the mass flow rate of the recycle stream in line 154) to the (mass flow rate the combined stream in line 144).
In an aspect, the alkylated aromatic product stream in line 152 may be passed to an optional third treatment unit 155. If no hydrotreating unit is employed upstream of the alkylation unit 150, the third treatment unit may be a hydrotreating unit. In the third hydrotreating unit 155, the alkylated aromatic product stream in line 152 may be contacted with a hydrotreating catalyst in a hydrogen environment. The third hydrotreating unit 155 may comprise one or more of the hydrotreating catalyst as previously described and be operated as the hydrotreating unit previously described. Hydrotreating may serve to hydrodeoxygenate oxygenates and hydrogenate unsaturated alkyl groups in the alkylated aromatic product stream in line 152.
A hydrotreated aromatic product stream is taken in line 156 from the third hydrotreating unit 155 and can be used as a biofuel or a motor biofuel. In accordance with the present disclosure, the third hydrotreating unit 155 is used to remove the oxygen components. When the third hydrotreating unit 155 is used, the second hydrotreating unit 140 is not used and the aromatic rich bio-oil stream in line 132 is passed directly to the alkylation unit 150. In another aspect, the third hydrotreating unit 155 is optionally used and the alkylated aromatic product stream in line 152 may be directly used as a biofuel or a motor biofuel. The alkylated aromatic product stream in line 152 may be further processed to provide the biofuel or the motor biofuel.
In another embodiment, the alkylated aromatic product stream in line 152 may be processed in an optional hydrogenation unit 160 to hydrodeoxygenate the alkylated aromatic product stream before it is separated into one or more liquid fuels. In an aspect, the alkylated aromatic product stream in line 152 may undergo catalytic hydrogenation. In hydrogenation unit 160, the alkylated aromatic product stream in line is catalytically reacted with hydrogen in a hydrogenation reactor in the presence of a supported hydrogenation catalyst to produce a hydrogenated effluent stream. The hydrogenation reactor may be operated at a temperature of about 50° C. to about 400° C. and a pressure of about 980 kPa (g) to about 9810 kPa (g). In an exemplary embodiment, the hydrogenation catalyst comprises sulfur and one or more of molybdenum, tungsten, cobalt, and/or nickel. The hydrogenated effluent stream is further fractionated to provide a diesel stream and a jet fuel stream. The jet fuel stream is taken in line 162 and the diesel stream is taken in line 164 from the hydrogenation unit 160. The jet fuel stream in line 162 is a green jet fuel and the diesel stream in line 164 is a green diesel in accordance with the present disclosure.
Propylene was taken as alkylating agent for the alkylation of an aromatic rich bio-oil stream in line 142. The aromatic rich bio-oil stream predominantly comprised BTX. A combined feed stream in line 144 with a BTX to propylene molar ratio of 2 to 2.2 was used for the study. The BTX stream was alkylated to produce the alkylated aromatic product. The study was performed at various reactor inlet temperatures and recycle mass flow rates. The results are plotted in the graph shown in
While the following is described in conjunction with specific embodiments, it will be understood that this description is intended to illustrate and not limit the scope of the preceding description and the appended claims.
A first embodiment of the present disclosure is a process of producing jet fuel, comprising separating lignin from a lignocellulosic biomass to provide a lignin stream; pyrolyzing the lignin stream and/or hydrotreating the lignin stream to produce an aromatic rich bio-oil stream; and alkylating aromatics in the aromatic rich bio-oil stream with an alkylating agent to produce an alkylated aromatic product stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the alkylating agent is an alcohol stream comprising one or more alcohols selected from ethanol, iso-butanol, and propanol. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the step of separating lignin comprises fermenting the lignocellulosic biomass; and separating the lignin stream and an alcohol stream from a fermented lignocellulosic biomass. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the alkylating agent is an olefinic stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph further comprising hydrotreating the aromatic rich bio-oil stream to remove oxygenates from the aromatic rich bio-oil stream; fractionating a de-oxygenated bio-oil stream to produce an aromatic naphtha stream; and alkylating the aromatic naphtha stream with the alkylating agent to produce the alkylated aromatic product stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph further comprising hydrogenating the alkylated aromatic product stream to produce a jet fuel stream and a diesel stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph further comprising hydrotreating the alkylated aromatic product stream to produce jet fuel. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the step of alkylating aromatics comprises an alkylation temperature of about 50° C. to about 400° C. and an alkylation pressure of about 1000 kPa to about 10000 kPa. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the step of pyrolyzing the lignin stream comprises a pyrolysis temperature of about 500° C. to about 700° C. and a pyrolysis pressure of about 100 kPa to about 1000 kPa. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the step of hydrotreating the lignin comprises a hydrotreating temperature of about 300° C. to about 400° C. and a hydrotreating pressure of about 4000 kPa to about 14000 kPa. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the alcohol stream comprises ethanol. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the step of hydrogenating the alkylated aromatic product stream comprises contacting the alkylated aromatic product stream and a hydrogen stream with a catalyst at a temperature of about 50° C. to about 400° C. and a pressure of about 980 kPa (g) to about 9810 kPa (g). An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the step of separating the lignin stream comprises separating a liquid stream from the fermented lignocellulosic biomass; fractionating the liquid stream to provide an overhead alcohol stream and a bottoms stream comprising lignin.
A second embodiment of the present disclosure is a process of producing jet fuel, comprising separating lignin from a lignocellulosic biomass to provide a lignin stream; pyrolyzing the lignin stream and/or hydrotreating the lignin stream to produce an aromatic rich bio-oil stream; and alkylating aromatics in the aromatic rich bio-oil stream with an alcohol to produce an alkylated aromatic product stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the alcohol is taken from an alcohol stream separated from the lignocellulosic biomass. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, wherein the step of separating lignin comprises fermenting the lignocellulosic biomass; and separating the lignin stream and an alcohol stream from a fermented lignocellulosic biomass. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph further comprising hydrotreating the aromatic rich bio-oil stream to remove oxygenates from the aromatic rich bio-oil stream; fractionating a de-oxygenated bio-oil stream to produce an aromatic naphtha stream; and alkylating the aromatic naphtha stream with the alkylating agent to produce the alkylated aromatic product stream.
A third embodiment of the present disclosure is a process of producing jet fuel, comprising separating lignin from a lignocellulosic biomass to provide a lignin stream; pyrolyzing the lignin stream and/or hydrotreating the lignin stream to produce an aromatic rich bio-oil stream; alkylating aromatics in the aromatic rich bio-oil stream with an alkylating agent to produce an alkylated aromatic product stream; and hydrogenating the alkylated aromatic product stream to produce a jet fuel stream and a diesel stream. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the third embodiment in this paragraph, wherein the alkylating agent is an alcohol stream separated from the lignocellulosic biomass. An embodiment of the present disclosure is one, any or all of prior embodiments in this paragraph up through the third embodiment in this paragraph wherein the step of hydrogenating the alkylated aromatic product stream comprises contacting the alkylated aromatic product stream and a hydrogen stream with a catalyst at a temperature of about 50° C. to about 400° C. and a pressure of about 980 kPa (g) to about 9810 kPa (g).
Without further elaboration, it is believed that using the preceding description that one skilled in the art can utilize the present disclosure to its fullest extent and easily ascertain the essential characteristics of this disclosure, without departing from the spirit and scope thereof, to make various changes and modifications of the disclosure and to adapt it to various usages and conditions. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limiting the remainder of the disclosure in any way whatsoever, and that it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
In the foregoing, all temperatures are set forth in degrees Celsius and, all parts and percentages are by weight, unless otherwise indicated.
| Number | Date | Country | |
|---|---|---|---|
| 63616443 | Dec 2023 | US |
