# US 9,434,885 B2 · Methods for producing bio-oil > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,434,885 B2 - Document ID: US9434885B2 - Status: Granted - Kind: B2 - Application number: 13/777,020 - Filed: 2013-02-26 - Published: 2014-08-28 - Granted: 2016-09-06 - Earliest claimed: 2013-02-26 - Assignees: The United States of America as represented by the Secretary of Agriculture - Applicants: The United States of America, as represented by the Secretary of Agriculture - Inventors: Charles A. Mullen; Akwasi A. Boateng; Neil M. Goldberg - Web page: https://patentgrep.com/patent/US9434885B2 ## CPC - C10B 53/02: of cellulose-containing material (production of pyroligneous acid C10C5/00) - C10B 49/08: in dispersed form - Y02E 50/10: Biofuels, e.g. bio-diesel - Y02P 20/145: the feedstock being materials of biological origin - C10B: DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS (cracking oils C10G; underground gasification of minerals E21B43/295) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract Methods for producing bio-oil from a feedstock (e.g., lignocellulosic) involving (1) pyrolyzing the feedstock in an inert atmosphere in a reactor to produce bio-oil, bio-char and non-condensable gases; (2) recycling 50 to about 85% of the non-condensable gases to the reactor to produce deoxygenated bio-oil; wherein the method is conducted in the absence of oxygen and wherein the method does not utilize externally added catalysts. ## Claims ### Claim 1 A method for producing bio-oil from a feedstock, said method comprising (1) pyrolyzing said feedstock in an inert atmosphere in a reactor to produce bio-oil, bio-char and non-condensable gases; (2) returning said non-condensable gases as a recycle gas to said reactor to produce deoxygenated bio-oil; wherein after (2) the atmosphere in said reactor comprises 50 to about 85% recycle gas and is held at steady state; wherein said method is conducted in the absence of oxygen and wherein said method does not utilize externally added catalysts; wherein said feedstock is a lignocellulosic feedstock; wherein benzene, toluene and xylene are produced after (2). ### Claim 2 (depends on 1) The method according to claim 1, wherein after (2) the atmosphere in said reactor comprises about 70% recycle gas. ### Claim 3 (depends on 1) The method according to claim 1, wherein the combination of benzene, toluene and xylene produced after (2) is about 5 times the combination of benzene, toluene and xylene produced with no recycling of said non-condensable gases after (1). ### Claim 4 (depends on 1) The method according to claim 1, wherein the combination of benzene, toluene and xylene produced after (2) is about 10 times the combination of benzene, toluene and xylene produced with no recycling of said non-condensable gases after (1). ### Claim 5 (depends on 1) The method according to claim 1, wherein the combination of benzene, toluene and xylene produced after (2) is about 15 times the combination of benzene, toluene and xylene produced with no recycling of said non-condensable gases after (1). ### Claim 6 (depends on 1) The method according to claim 1, wherein the combination of benzene, toluene and xylene produced after (2) is about 20 times the combination of benzene, toluene and xylene produced with no recycling of said non-condensable gases after (1). ### Claim 7 (depends on 1) The method according to claim 1, wherein the combination of benzene, toluene and xylene produced after (2) is about 25 times the combination of benzene, toluene and xylene produced with no recycling of said non-condensable gases after (1). ### Claim 8 (depends on 1) The method according to claim 1, wherein the bio-oil produced after (2) has a C:O ratio of at least about 1.6 times the C:O ratio of products produced with no recycling of said non-condensable gases after (1). ### Claim 9 (depends on 1) The method according to claim 1, wherein the bio-oil produced after (2) has a C:O ratio of at least about 1.9 times the C:O ratio of products produced with no recycling of said non-condensable gases after (1). ### Claim 10 (depends on 1) The method according to claim 1, wherein the bio-oil produced after (2) has a C:O ratio of at least about 4.3 times the C:O ratio of products produced with no recycling of said non-condensable gases after (1). ### Claim 11 (depends on 1) The method according to claim 1, wherein the bio-oil produced after (2) has a C:O ratio of at least about 5.3 times the C:O ratio of products produced with no recycling of said non-condensable gases after (1). ### Claim 12 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 70% of the CO2 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 13 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 50% of the CO2 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 14 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about two times more H2 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 15 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about twenty times more H2 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 16 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about two times more CH4 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 17 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about six times more CH4 compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 18 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 1 mole % C2H6 compared to products produced with no recycling of said non-condensable gases which contained about 0 to about 0.4 mole % C2H6 after (1). ### Claim 19 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 2.7 mole % C2H6 compared to products produced with no recycling of said non-condensable gases which contained about 0 to about 0.4 mole % C2H6 after (1). ### Claim 20 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 1 mole % C3H8 compared to products produced with no recycling of said non-condensable gases which contain about 0 to 0.1 mole % C3H8 after (1). ### Claim 21 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 2.6 mole % C3H8 compared to products produced with no recycling of said non-condensable gases which contain about 0 to 0.1 mole % C3H8 after (1). ### Claim 22 (depends on 1) The method according to claim 1, wherein the non-condensable gases produced after (2) contain about 1.6 to about 2.8 times more MJ/kg compared to products produced with no recycling of said non-condensable gases after (1). ### Claim 23 (depends on 1) Deoxygenated bio-oil produced by the method according to claim 1; wherein said deoxygenated bio-oil after step (2) has an oxygen content of no more than 12.54 wt %/o (dry basis) and wherein said deoxygenated bio-oil has higher heating value of at least 33.2 MJ/kg. ### Claim 24 (depends on 1) The method according to claim 1, wherein said reactor is a bubbling fluidized bed pyrolysis system. ### Claim 25 (depends on 1) The method according to claim 1, wherein after step (2) the atmosphere in said reactor comprises about 65 to about 80% recycle gas wherein the recycle gas contains at least 40.3 mole % CO, at least 12 mole % H2, and at most 20.7 mole % CO2. ### Claim 26 (depends on 1) The method according to claim 1, wherein said deoxygenated bio-oil has an oxygen content of no more than about 12.5 wt % (dry basis). ### Claim 27 (depends on 1) The method according to claim 1, wherein said deoxygenated bio-oil has an oxygen content of no more than about 25.22 wt % (dry basis). ### Claim 28 (depends on 1) The method according to claim 1, wherein said deoxygenated bio-oil has higher heating value of at least 33.2 MJ/kg. ### Claim 29 (depends on 1) The method according to claim 1, wherein said deoxygenated bio-oil has higher heating value of at least 31.2 MJ/kg. ### Claim 30 (depends on 1) The method according to claim 1, wherein said method comprises recycling about 60 to about 85% of said non-condensable gases to said reactor to produce deoxygenated bio-oil. ### Claim 31 (depends on 1) The method according to claim 1, wherein said method comprises recycling about 65 to about 80% of said non-condensable gases to said reactor to produce deoxygenated bio-oil. ### Claim 32 (depends on 1) Deoxygenated bio-oil produced by the method according to claim 1; wherein said deoxygenated bio-oil after step (2) has an oxygen content of no more than 25.22 wt % (dry basis) and wherein said deoxygenated bio-oil has higher heating value of at least 31.2 MJ/kg.