Nitrogen removal and electricity production at a double-chamber microbial fuel cell with cathode nitrite denitrification

Double-chamber microbial fuel cell was applied to investigate the performance of the electricity production and nitrite denitrification through feeding nitrite into the cathode. Factors influencing denitrification performance and power production, such as external resistance, influent nitrite concentration and Nitrite Oxygen Bacteria inhibitors, were studied. The results show that when the concentration of nitrite nitrogen and external resistance were 100 mg L^-1 and 10 Ω, respectively, the nitrite denitrification reached the best state. The NaN₃ can inhibit nitrite oxidation effectively; meanwhile, the nitrite denitrification with N₂O as the final products was largely improved. The [Formula: see text] was reduced to [Formula: see text], causing the cathode denitrification coulombic efficiency to exceed 100%. In chemoautotrophic bio-nitrification, microorganisms may utilize H₂O to oxidize nitrite under anaerobic conditions. Proteobacteria might play a major role in the process of denitrification in MFC.