Comparative Study of Three Cathodic Electron Acceptors on the Performance of Medatiorless Microbial Fuel Cell

摘要

Microbial Fuel Cells (MFC) are capable of converting the chemical energy stored in the chemical compounds in a biomass to electrical energy with the aid of microorganisms. A better understanding of the relationship between the microbiological and electrical aspects of fuels cells is needed prior to successful MFC application. MFC constructed employing low-cost materials (salt bridge, graphite electrodes) without addition of any toxic mediators and using glucose (3 g L-1) as substrate and three different electron acceptors potassium permanganate (KMnO4), potassium ferricyanide (K3[Fe(CN)6]) and potassium dichromate (K2Cr2O7) in the cathode chamber without pH adjustment was assessed in the present study. The results showed that MFC performance with KMnO4 was superior than K3[Fe(CN)6] and K2Cr2O7. Maximum voltage generation (OCV) and power density for KMnO4 were 1.04 V and 7.29 mW m-2. Performance of MFC with K3[Fe(CN)6] and K2Cr2O7 was much lower with a OCV and power density of 0.71 V; 0.92 mW m-2 and 0.56 V; 0.79 mW m-2, respectively. Demonstrating that KMnO4 can be used as an effective cathodic electron acceptor to enhance power output on MFC.