Bicarbonate and carbonate as hydroxide carriers in a biological fuel cell

摘要

The present invention relates generally to a process that helps alleviate the pH gradient between anode and cathode compartments in any biological fuel cell or electrolytic cell configuration in which a pH gradient between anode and cathode is limiting the voltage efficiency. By providing acid to the cathode compartment in the form of CO2, the pH gradient is reduced and voltage efficiency and power output are increased. In one embodiment, carbon dioxide produced in the anode chamber is recycled to the cathode chamber.

主权项

1. A method of operating a fuel cell having a cathode chamber, an anode chamber, and a pH gradient between the cathode and anode chambers, comprising:
supplying a gas flow to the cathode chamber; wherein the gas flow contains carbon dioxide at a concentration of less than or equal to about 5%, wherein at least a portion of the carbon dioxide contained in the gas flow was produced in the anode chamber and recycled to the cathode chamber.