Evaluation of the Electrochemical Characteristic of Microbial Fuel Cells Including Carbon-felt Bioanodes and Activated-carbon Cathodes

다국어 초록 (Multilingual Abstract)

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts biomass energy in wastewater into electrical energy and purify wastewater by using a microbial electrochemical reaction. For the practical implementation of MFC as a next-generation wastewater treatment process, MFC performance should be enhanced far more than the current level. Characterizations of the electrochemistry of MFC is very important in developing bio-electrochemical energy producing wastewater treatment process. Compared to the development of MFC technology, however, understanding of its electrochemical characterization is still insufficient. The main reason is that its electrochemical analysis is very difficult due to the complex nature of the anode biofilm, which is a key to generating electricity. In this experiment, the influence of the measurement potential of impedance and the scanning rate for polarization curve on the MFC electrochemistry was investigated. The experiment was performed after stabilizing the system for accurate measurement. Unlike the previous batch tests showing the lowest anodic impedance at -400 ㎷ vs. Ag/AgCl, the anodic impedance decreased and the current production increased as the anode potential increased up to +5.7 mV vs. Ag/AgCl in the continuous flow MFC. The polarization curves were produced at two scanning rates (1 and 0.1 ㎷/s) in a continuous mode, and those electrochemical data were comparatively analyzed. The rapid scan rate has the advantage of being able to collect data in a short time, but the measured data differs from the performance value when operating the MFC with a constant external resistance. When it is difficult to maintain a steady state for a long time in an MFC, it will be possible to produce polarization curves in a short time with a faster scanning rate. When performance analysis is needed, the comparative analysis would be possible among the data at different conditions through extrapolation.