Influential fuel cell systems including effective cathodes and use with remediation efforts

• US 20090029198A1
• Filed: 03/24/2008
• Published: 01/29/2009
• Est. Priority Date: 03/22/2007
• Status: Active Grant

• Current Assignee: Advanced Environmental Technologies LLC (EIS Holdings LLC)
• Original Assignee: The University of Wyoming Research Corporation
• Inventors: Jin, Song, Morris, Jeffrey M.
• Granted Patent: US 7,858,243 B2
• Time in Patent Office: Days
• US Class Current: 429/401
• CPC Class Codes: H01M 2008/1095 Fuel cells with polymeric electrolytes
• CPC Class Codes: H01M 4/9016 Oxides, hydroxides or oxygenated metallic salts
• CPC Class Codes: H01M 8/16 Biochemical fuel cells, i.e. cells in which microorganisms function as catalysts
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

Embodiments may include efficient fuel cell systems including an anode, a cathode, a lead-containing cathode catalyst, at least one proton exchange connector, and perhaps even an external circuit between the anode and the cathode. Other embodiments may include enhanced degradation of contaminants in environmental media such as perhaps petroleum hydrocarbon in groundwater with microbial fuel cells and the like.

Claims

1. A method for efficient electrochemical energy conversion comprising the steps of:

generating electrons and protons in an anode chamber of a fuel cell, wherein said anode chamber comprises at least one anode;

transferring said electrons from said anode chamber to a cathode chamber of said fuel cell via an external circuit;

driving an electrical current through said external circuit with a lead-containing cathode catalyst and at least one cathode in said cathode chamber;

connecting said anode chamber and said cathode chamber with at least one proton exchange connector; and

generating electrical power.

2. The method according to claim 1 wherein said fuel cell is selected from a group consisting of a hydrogen fuel cell, a microbial fuel cell, an enzyme fuel cell, a biofuel cell, a light fuel cell, and a hybrid fuel cell based on any said hydrogen fuel cell, microbial fuel cell, enzyme fuel cell, biofuel cell, or light fuel cell.

3. The method according to claim 1 wherein said lead-containing cathode catalyst comprises a lead dioxide (PbO₂) cathode catalyst.

4. The method according to claim 1 wherein said step of transferring said electrons from said anode chamber to said cathode chamber comprises the step of transferring said electrons from a closed anaerobic anode chamber to said cathode chamber.

5. The method according to claim 1 and further comprising the step of utilizing ambient air as an oxygen supply in said cathode chamber.

6. The method according to claim 1 and further comprising the step of utilizing electrons transferred from said anode chamber to said cathode chamber with a cathode electron acceptor.

7. The method according to claim 6 wherein said cathode electron acceptor is selected from a group consisting of oxygen, oxygen-releasing compounds, and peroxides.

8. The method according to claim 6 wherein said cathode electron acceptor comprises compounds with oxidizing potentials higher than oxygen.

9. The method according to claim 8 wherein said compounds with oxidizing potentials higher than oxygen are selected from a group consisting of halogenated compounds, oxidants of permanganate, percarbonate, peroxide, persulfate, and ozone.

10. The method according to claim 6 wherein said cathode electron acceptor comprises a compound with a lower oxidizing potential than oxygen.

11. The method according to claim 10 wherein said compound with said lower oxidizing potential than oxygen is selected from a group consisting of nitrate, sulfate, iron, manganese, arsenate, selenate, uranium, and chromate.

12. The method according to claim 1 wherein said step of generating said electrons and said protons in said anode chamber comprises the step of generating said electrons and said protons by anaerobic degradation of substances.

13. The method according to claim 1 wherein said step of generating said electrons and said protons in said anode chamber comprises the step of generating said electrons and said protons by oxidation of substances.

14. The method according to claim 12 wherein said substances are selected from a group consisting of organic and inorganic substances.

15. The method according to claim 12 wherein said anaerobic degradation utilizes bacteria selected from a group consisting of iron-reducing bacteria, denitrifying bacteria populations, sulfate-reducing bacteria populations, methanovenic bacteria, fermenting bacteria, Citrobacter sp., Pseudomonas sp., Strehotrophomonas sp., Shewanella sp. ANA-3, Alishewanella sp., γ

-Proteobacteria, Citramonas sp., Desulfovibrio sp., and Dechloromonas.

16. The method according to claim 1 wherein said step of connecting said anode chamber and said cathode chamber with at least one proton exchange connector comprises the step of connecting said anode chamber and said cathode chamber with a proton exchange membrane between said anode chamber and said cathode chamber.

17. The method according to claim 1 wherein said step of connecting said anode chamber and said cathode chamber with at least one proton exchange connector comprises the step of connecting said anode chamber with said cathode chamber with at least one proton bridge.

18. The method according to claim 1 wherein said step of connecting said anode chamber and said cathode chamber with at least one proton exchange connector comprises the step of connecting said anode chamber with said cathode chamber with a conductive liquid medium between said anode chamber and said cathode chamber.

19. The method according to claim 17 wherein said step of connecting said anode chamber with said cathode chamber with said at least one proton bridge comprises the step of connecting multiple anodes in said anode chamber to at least one cathode in said cathode chamber with multiple proton bridges.

20. The method according to claim 1 wherein said anode chamber comprises an anode and at least one substance selected from a group consisting of hydrogen, enzymes, microorganisms, glucose, sulfur, iron, acetate, wastewater, subsurface contaminants, sulfide, petroleum hydrocarbons, diesel range organics, glucose, sewage sludge, organic compounds, inorganic compounds, gasoline and diesel.

21. The method according to claim 1 wherein said at least one cathode comprises at least one mesh cathode.

22. The method according to claim 1 and further comprising the step of locating said at least one anode in an environmental media.

23. The method according to claim 22 wherein said environmental media is selected from a group consisting of an underground environment, a saturated subsurface, an unsaturated subsurface, wastewater, soil, groundwater, sediment, surface water, and petroleum-impacted saturated soils.

24. The method according to claim 1 wherein said anode chamber and said cathode chamber comprise a single cell system.

25. The method according to claim 1 wherein said anode chamber and said cathode chamber comprise a double cell system.

26. An efficient electrochemical energy conversion device comprising:

at least one anode;

at least one cathode;

a lead-containing cathode catalyst;

at least one proton exchange connector between said at least one anode and said at least one cathode; and

an external circuit between said at least one anode and said at least one cathode providing electrons from said at least one anode to said at lease one cathode.

27-47. -47. (canceled)

48. A method for efficient electrochemical energy conversion comprising the steps of:

generating electrons and protons in an anode chamber of a fuel cell, wherein said anode chamber comprises at least one anode;

transferring said electrons from said anode chamber to a cathode chamber of said fuel cell via an external circuit;

driving an electrical current through said external circuit with a manganese-containing cathode catalyst and at least one cathode in said cathode chamber;

connecting said anode chamber and said cathode chamber with at least one proton exchange connector; and

generating electrical power.

49. An efficient electrochemical energy conversion device comprising:

at least one anode;

at least one cathode;

a manganese-containing cathode catalyst;

at least one proton exchange connector between said at least one anode and said at least one cathode; and

an external circuit between said at least one anode and said at least one cathode providing electrons from said at least one anode to said at least one cathode.

50. A double chamber dual acting in-situ microbial fuel cell device for waste remediation and energy generation comprising:

at least one anode in a closed anaerobic anode chamber located within an environmental media;

at least one anaerobic microbial population and at least one contaminant in said closed anaerobic anode chamber located within said environmental media;

an open cathode chamber positioned at or near a surface of said environmental media;

a proton exchange connector connecting said closed anaerobic anode chamber and said open cathode chamber to transfer protons from said at least one anode of said closed anaerobic anode chamber to at least one cathode of said open cathode chamber; and

an external circuit between said closed anaerobic anode chamber and said open cathode chamber to create electrical power over a potential difference from said closed anaerobic anode chamber and said open cathode chamber.

51-70. -70. (canceled)

71. A method of multi-purpose in-situ microbial fuel cell functions for waste remediation and energy generation comprising the steps of:

providing an environmental media having at least one microbial population and at least one contaminant;

creating a closed anaerobic anode chamber within said environmental media;

catabolizing said at least one contaminant in said environmental media with said at least one microbial population to generate electrons and protons in said closed anaerobic anode chamber;

degrading at least some of said at least one contaminant;

extracting electrons from said closed anaerobic anode chamber with at least one anode in said closed anaerobic anode chamber;

transferring said electrons from said closed anaerobic anode chamber to an open cathode chamber through an external circuit, wherein said open cathode chamber is located at or near a surface of said environmental media;

generating electrical power from said transfer of said electrons from said closed anaerobic anode chamber to said open cathode chamber;

transferring protons from said closed anaerobic anode chamber to said open cathode chamber with a proton exchange connector between said at least one anode to at least one cathode of said open cathode chamber; and

reacting oxygen with said protons in said open cathode chamber to create by-products.

72-92. -92. (canceled)