Patent ID: 7572546

Claim:
A bio-fuel cell system for concurrent production of electrical power and single-cell protein, and consumption of carbon dioxide (CO 2 ), comprising; a cathode compartment containing a cathode electrode with an aqueous solution containing ferric ions (Fe 3+ ) being circulated into said cathode compartment with a reaction at the cathode electrode being reduction of ferric ions at the cathode electrode in a reaction given by 4Fe 3+ +4e − =4Fe 2+ ; an anode compartment containing an anode electrode; with a fuel having a hydrogen constituent being pumped directly into said anode compartment, said anode compartment being separated from said cathode compartment by a membrane permeable to protons, a reaction at the anode electrode being electrochemical oxidation of at least the hydrogen constituent of the fuel to produce electrons (e − ) and protons (H + ), wherein protons (H+) formed by the oxidation of hydrogen cross the proton exchange membrane into the cathode compartment; and a bioreactor containing chemolithotrophic microorganisms and dissolved nutrients to facilitate growth of the chemolithotrophic microorganisms, a pump for pumping a fluid containing oxygen (O 2 ) and atmospheric carbon dioxide into the bioreactor, the bioreactor being in flow communication with the cathode compartment so that an aqueous solution containing ferrous ions (Fe 2+ ) and protons (H + ) is circulated from the cathode compartment to the bioreactor where the ferrous ions (Fe 2+ ) are oxidized by the chemolithotrophic microorganisms to ferric ions (Fe 3+ ) in an aerobic oxidation reaction given by 4Fe 2+ +4H + +O 2 =4Fe 3+ +2H 2 O, and wherein single-cell protein production and carbon dioxide consumption responsively occurs due to fixation of the carbon dioxide (CO 2 ) by the chemolithotrophic microorganisms in the presence of the dissolved nutrient salts and ferrous ions; a pump for pumping a fluid containing said ferric ions (Fe 3+ ) into said cathode compartment from said bioreactor; and wherein electrical power is obtained by making electrical connection between a load and the anode and cathode electrodes.