Fracking with CO2 for shale gas reforming to methanol

Patent metadata

Field	Value
Publication number	US-10131599-B2
Application number	US-201415036506-A
Country	US
Kind code	B2
Filing date	Nov 14, 2014
Priority date	Nov 21, 2013
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A method of producing methanol from shale gas and CO2 by the exclusive dry CO2 fracking of shale rock by injection of gaseous CO2 at a pressure between 10 and 100 atm to extract shale gas and recover it together with used CO2; combining and admixing produced shale gas containing CO2 and steam to produce a mixture of methane:carbon dioxide:water having a molar ratio of 3:1:2 for conducting the bi-reforming reaction to form a mixture of hydrogen and carbon monoxide having a molar ratio of 2:1 to 2.1:1; and converting the hydrogen and carbon monoxide under conditions sufficient to exclusively form methanol.

First claim

What is claimed is:

1. A method of producing methanol by obtaining a shale gas and CO 2 mixture from exclusive dry CO 2 fracking, which comprises:
dry fracking of an underground shale rock formation by injection of dry, gaseous CO 2 into the shale rock at an injection pressure of between 10 and 100 atm to cause fracking of the rock and subsequently generate a shale gas mixture comprising methane, carbon dioxide and contaminants;
recovering the shale gas mixture from the fracked shale rock and separating it for CO 2 to be recycled with cleaning to remove CO 2 and contaminants including hydrogen sulfide and provide a cleaned shale gas mixture consisting essentially of methane;
combining the cleaned shale gas mixture with recycled CO 2 that is recovered from dry fracking and H 2 O in amounts sufficient to produce a mixture of methane:carbon dioxide:water at a molar ratio of 3:1:2;
conducting a single-step bi-reforming reaction with the methane:carbon dioxide:water mixture to form only carbon monoxide and hydrogen as follows:
3CH 4 +CO 2 +2H 2 O→4CO+8H 2

in a mixture having a molar ratio of hydrogen and carbon monoxide of 2:1 to 2.1:1; and
converting the mixture of hydrogen and carbon monoxide under conditions sufficient to exclusively form methanol, as follows:
4CO+8H 2 →4CH 3 OH.

2. The method of claim 1 , wherein the CO 2 for dry fracking is derived from any natural or industrial source and is pressurized to the injection pressure prior to injection.

3. The method of claim 2 , wherein the derived CO 2 is pressurized, generally between 10 and 100 atm prior to injection into the shale rock.

4. The method of claim 1 , which further comprises providing needed energy for the bi-reforming reaction from combustion of part of the methane from the recovered shale gas or from one or more renewable sources of energy or atomic energy.

5. The method of claim 1 , wherein the bi-reforming reactions are carried out over a catalyst at a temperature between about 800° C. and 1100° C. and a pressure of 5 to 40 atm, wherein the catalyst comprises V, Ti, Ga, Mg, Cu, Ni, Mo, Bi, Fe, Mn, Co, Nb, Zr, La or Sn, or oxides thereof in the form of a single metal catalyst, a single metal oxide catalyst, a mixed catalyst of a metal and a metal oxide, or a mixed catalyst of at least one metal oxide and another metal oxide, the catalyst optionally being provided on an oxide support.

6. The method of claim 1 , wherein the molar mixture of hydrogen and carbon monoxide is present at a molar ratio of approximately 2.05 to 1 for subsequent methanol synthesis.

7. The method of claim 1 , which further comprises dehydrating all or a portion of the methanol to dimethyl ether and water and recycling the water from the dehydration to the bi-reforming reaction.

8. The method of claim 7 , which further comprises converting the dimethyl ether in the presence of an acid-base or zeolite catalyst under conditions sufficient to form one of ethylene propylene.

9. The method of claim 8 , which further comprises converting either the ethylene or propylene under conditions sufficient to form higher olefins, synthetic hydrocarbons, aromatic compounds, or a product produced from the foregoing.

10. A method of providing an essential economic and replenishable energy source material which comprises:
obtaining methanol from the method of claim 1 ; and
converting the methanol to a hydrocarbon fuel, dimethyl ether or products derived from dimethyl ether.

11. A method of providing a commonly useful fuel for internal combustion engines, which comprises:
obtaining methanol from the method of claim 1 ; and
admixing the methanol to or replacing gasoline or diesel fuel with methanol for combustion in modified or adjusted internal combustion engines.

12. The method of claim 1 , which further comprises converting the methanol as an essential economic and replenishable energy source material to hydrocarbon fuels, dimethyl ether or products derived from dimethyl ether.

13. The method of claim 1 , which further comprises preparing a commonly useful fuel for internal combustion engines by admixing the methanol to or replacing gasoline or diesel fuel with methanol for combustion in modified or adjusted internal combustion engines.

14. A method of producing methanol by obtaining a shale gas and CO 2 mixture from exclusive dry CO 2 fracking, which comprises:
dry fracking of shale rock by injection of gaseous CO 2 into the shale rock at an injection pressure of between 10 and 100 atm to cause fracking of the rock and generate a shale gas mixture;
recovering the shale gas mixture from the fracked shale rock and separating it for CO 2 to be recycled with cleaning to remove CO 2 and contaminants including hydrogen sulfide and provide a cleaned shale gas mixture consisting essentially of methane;
combining the cleaned shale gas mixture with recycled CO 2 that is recovered from dry fracking and H 2 O in amounts sufficient to produce a mixture of methane:carbon dioxide:water at a molar ratio of 3:1:2;
conducting a single-step bi-reforming reaction with the methane:carbon dioxide:water mixture to form only carbon monoxide and hydrogen as follows:
3CH 4 +CO 2 +2H 2 O→4CO+8H 2

in a mixture having a molar ratio of hydrogen and carbon monoxide of 2:1 to 2.1:1; and
converting the mixture of hydrogen and carbon monoxide under conditions sufficient to exclusively form methanol, as follows:
4CO+8H 2 →4CH 3 OH,

wherein methanol is synthesized over Cu/ZnO catalysts and the bireforming reaction is conducted at atmospheric pressure in a flow reactor at a temperature between 220 to 250° C.

Assignees

• Univ Southern California

Inventors

• Olah George A
• Prakash G K Surya

Classifications

• Y02P90/70

  Combining sequestration of CO2 and exploitation of hydrocarbons by injecting CO2 or carbonated water in oil wells · CPC title

• C07C41/09

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• C07C1/24

  by elimination of water · CPC title

• E21B43/26

  by forming crevices or fractures · CPC title

• E21B43/267 Primary

  reinforcing fractures by propping · CPC title