Bioelectricity production from fermentable household waste extract using a single chamber microbial fuel cell

A four air-cathode single chamber membrane-less microbial fuel cell (MFC) was developed and used to produce energy when fed with fermentable household waste extract (FORBI; 0.8 g COD/L). The employment of MnO2 as the cathode catalyst at a loading of 89 mg /cm2, the use of food residue biomass (FORBI) and the single chamber design provided a maximum power output of 3.2 mW in 120 ml anolyte volume under Open Circuit Voltage (OCV) conditions in three batch operation cycles. The COD removal was over 78% for all operation cycles. The total resistance of the proposed design of the MFC was in the range of 12.21-12.78 Ω, which is significantly lower than the internal resistance of dual chamber MFCs. Electrochemical Impedance Spectroscopy verified the values of the internal resistance and gave an insight in the electrochemical processes occurring in the MFC. Gradual development and stabilization of an active biofilm is recorded with FORBI as substrate, while the electrode charge transfer reaction remained stable during the batch cycles.