# US 7,608,743 B2 · Efficient and selective chemical recycling of carbon dioxide to methanol, dimethyl ether and derived products > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,743 B2 - Document ID: US7608743B2 - Status: Granted - Kind: B2 - Application number: 11/766,408 - Filed: 2007-06-21 - Published: 2007-11-01 - Granted: 2009-10-27 - Earliest claimed: 2005-04-15 - Assignees: University of Southern California - Inventors: George A. Olah; G. K. Surya Prakash - Web page: https://patentgrep.com/patent/US7608743B2 ## CPC - C07C 29/136: of >C=O containing groups, e.g. —COOH - C07C 1/20: starting from organic compounds containing only oxygen atoms as heteroatoms - C07C 29/04: by hydration of carbon-to-carbon double bonds - C07C 29/14: of a —CHO group - C07C 29/141: with hydrogen or hydrogen-containing gases - C07C 29/149: with hydrogen or hydrogen-containing gases - C07C 41/09: by dehydration of compounds containing hydroxy groups - C07C 51/15: by reaction of organic compounds with carbon dioxide, e.g. Kolbe-Schmitt synthesis - C07C 67/08: by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds - C07C 67/38: by addition to an unsaturated carbon-to-carbon bond - C07C 68/01: from carbon monoxide and oxygen - C07C 68/02: from phosgene or haloformates - C25B 3/07: Oxygen containing compounds - C25B 3/25: Reduction - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - C25B: ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR (anodic or cathodic protection C23F13/00; single-crystal growth C30B) ## Abstract An efficient and environmentally beneficial method of recycling and producing methanol from varied sources of carbon dioxide including flue gases of fossil fuel burning powerplants, industrial exhaust gases or the atmosphere itself. Converting carbon dioxide by chemical or electrochemical reduction secondary treatment to produce essentially methanol, dimethyl ether and derived products. ## Claims ### Claim 1 An environmentally beneficial method of reducing the carbon dioxide content of the atmosphere and preparing a renewable fuel by separating and chemically recycling carbon dioxide from a natural or chemical source that would otherwise be present in or discharged into the atmosphere, which method comprises: separating the carbon dioxide from such source and producing methanol by hydrogenatively converting the carbon dioxide thus separated under conditions sufficient to produce methanol; utilizing the methanol thus produced as an energy storage and transportation material or as a fuel sufficient to generate energy while producing an exhaustion stream of the combustion that contains carbon dioxide; and recovering the carbon dioxide content of the combustion stream for use as the chemically recyclable source of carbon dioxide for preparing additional fuel. ### Claim 2 (depends on 1) The method of claim 1, wherein the carbon dioxide obtained from such source is hydrogenatively converted to methanol or derived products by catalytic, photochemical or electrochemical processes. ### Claim 3 (depends on 1) The method of claim 1 wherein the methanol is produced by hydrogentatively converting the carbon dioxide to form a reaction mixture that contains methanol, formic acid and formaldehyde, followed, without separation of the reaction mixture, by a treatment step conducted under conditions sufficient to convert the formaldehyde and formic acid to methanol. ### Claim 4 (depends on 3) The method of claim 3, which comprises reacting the formaldehyde with the co-formed formic acid as a hydrogen source, without separation of the reaction mixture, into methanol, including reacting of the formic acid with methanol to form methyl formate, followed by hydrogenating the methyl formate under conditions sufficient to form double the staffing amount of methanol. ### Claim 5 (depends on 4) The method of claim 4, wherein the hydrogen needed for the hydrogenation of methyl formate is obtained at least some part from cleavage of the formic acid from the reaction mixture. ### Claim 6 (depends on 1) The method of claim 1, wherein the hydrogen needed for the hydrogenative conversion of carbon dioxide is obtained by the reforming of methane or natural gas or by electrolysis of water using an available energy source. ### Claim 7 (depends on 1) The method of claim 1, wherein the available source of carbon dioxide is an exhaust stream from a fossil fuel burning power or industrial plant or a source accompanying natural gas and the available source would otherwise be released into the atmosphere or stored by sequestration underground or in the seas. ### Claim 8 (depends on 1) The method of claim 1 wherein the available source of carbon dioxide is the atmosphere with the carbon dioxide obtained by absorbing atmospheric carbon dioxide onto a suitable adsorbent followed by treating the adsorbent to release the adsorbed carbon dioxide therefrom. ### Claim 9 (depends on 8) The method of claim 8, wherein the adsorbent is treated by sufficient heating to release the adsorbed carbon dioxide. ### Claim 10 (depends on 8) The method of claim 8, wherein the adsorbent is treated by subjecting the adsorbent to sufficient reduced pressure to release the adsorbed carbon dioxide. ### Claim 11 (depends on 1) The method of claim 1, wherein the utilizing step further comprises dehydrating methanol under conditions sufficient to produce dimethyl ether; using the dimethyl ether as is or to generate the fuel; and recycling the carbon dioxide formed by combusting the generated fuel. ### Claim 12 (depends on 11) The method of claim 11, which further comprises utilizing the methanol or dimethyl ether as convenient energy storage and transportation materials in order to minimize or eliminate the disadvantages or dangers inherent in the use and transportation of hydrogen, LNG or LPG.