Process for producing electrical energy with the aid of a fuel cell

• US 20020025456A1
• Filed: 05/18/2001
• Published: 02/28/2002
• Est. Priority Date: 05/20/2000
• Status: Active Grant

• Current Assignee: Umicore AG & Company KG (Umicore S.A.)
• Original Assignee: dmc2 Degussa Metals Catalysts Cerdec AG (Vectra Corp.)
• Inventors: Diehl, Barbara, Lox, Egbert, Kreuzer, Thomas, Gieshoff, Jurgen, Vollmer, Helga
• Granted Patent: US 6,686,075 B2
• Time in Patent Office: Days
• US Class Current: 429/2
• CPC Class Codes: H01M 8/0662 Treatment of gaseous reactants or gaseous residues, e.g. cleaning
• CPC Class Codes: H01M 8/1007 with both reactants being gaseous or vaporised H01M8/12 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A process for producing electrical energy with the aid of a fuel cell, which includes the steps of reforming an organic fuel, removing carbon monoxide from the reformate, and reacting the hydrogen present in the reformate with oxygen, in a fuel cell, to thereby produce electrical energy. The carbon monoxide is removed from the reformate by treating the reformate in a bioreactor which contains a thermophilic microorganism strain which metabolizes carbon monoxide, under anaerobic conditions, to give carbon dioxide and hydrogen.

Claims

1. A process for producing electrical energy using a fuel cell, the process comprising:

reforming an organic fuel to produce a reformate;

removing carbon monoxide from the reformate by treating the reformate in a bioreactor which contains CO-dehydrogenase or a thermophilic microorganism strain which metabolizes carbon monoxide under anaerobic conditions to give carbon dioxide and hydrogen; and

reacting the hydrogen from the reformate with oxygen in a fuel cell to produce electrical energy.

2. The process according to claim 1, wherein the thermophilic microorganism strain comprises Carboxidothermus hydrogenoformans DSM 6008, and wherein the treating of the reformate is carried out at a temperature between 35 and 90°

C., at a pH between 5.0 and 8.0, and at a pressure between 1 and 10 bar.

3. The process according to claim 1, wherein the fuel cell is selected from the group consisting of a polymer electrolyte fuel cell and a phosphoric acid fuel cell.

4. The process according to claim 1, wherein the reformate is pre-treated in a preliminary, non-biological carbon monoxide conversion step before being treated in the bioreactor.

5. The process according to claim 4, wherein the preliminary pre-treatment step comprises a high temperature step and a low temperature step for carbon monoxide conversion.

6. The process according to claim 4, wherein the process is carried out using at least one gas storage tank before or after the step of treating the reformate in a bioreactor so that the reformate before the treating step, or the oxygen and hydrogen after the treating step, is stored in the at least one gas storage tank for a period of time.

7. The process according to claim 1, wherein the microorganism strain is cultivated on at least one member selected from the group consisting of yeast extract, peptone, and a substrate containing other proteins.

8. The process according to claim 1, wherein the microorganism strain or the CO-dehydrogenase enzyme is fixed in the reactor to support materials.

9. A polymer electrolyte fuel cell, comprising:

a polymer electrolyte membrane, which is coated on a first face with an anode catalyst, and on a second face with a cathode catalyst, wherein the anode catalyst and the cathode catalyst are each covered with a gas distributor structure for electrical contact and for supplying and removing reaction media; and

microorganisms, immobilized as whole cells on the gas distributor structure for the anode.

10. A polymer electrolyte fuel cell, comprising:

a polymer electrolyte membrane, which is coated on a first face with an anode catalyst, and on a second face with a cathode catalyst, wherein the anode catalyst and the cathode catalyst are each covered with a gas distributor structure for electrical contact and for supplying and removing reaction media; and

CO-dehydrogenase enzyme, immobilized on the gas distributor structure for the anode.

11. A process for removing carbon monoxide from a reformate of an organic fuel, the process comprising treating the reformate in a bioreactor which contains at least one member selected from the group consisting of CO-dehydrogenase and a thermophilic microorganism strain which metabolizes carbon monoxide under anaerobic conditions to give carbon dioxide and hydrogen.

14. The process according to claim 13, wherein the thermophilic microorganism strain comprises Carboxidothermus hydrogenoformans DSM 6008, and wherein the contacting of the reformate is carried out at a temperature between 35 and 90°

C., at a pH between 5.0 and 8.0, and at a pressure between 1 and 10 bar.

12. A process for producing hydrogen and carbon dioxide from the reformate of an organic fuel, the process comprising removing carbon monoxide from the reformate by treating the reformate in a bioreactor which contains at least one member selected from the group consisting of CO-dehydrogenase and a thermophilic microorganism strain which metabolizes carbon monoxide under anaerobic conditions to give carbon dioxide and hydrogen.

13. A process for producing electrical energy using a fuel cell, the process comprising:

reforming an organic fuel to produce a reformate;

contacting the reformate with CO-dehydrogenase or a thermophilic microorganism strain which metabolizes carbon monoxide under anaerobic conditions to give carbon dioxide and hydrogen; and

reacting the hydrogen from the reformate with oxygen in a fuel cell to produce electrical energy.