| H-type microbial fuel cells (MFCs) in which domestic wastewater was used as substrate and graphite sticks were used as electrodes were constructed to investigate the effect of cathode surface and membrane area on the performance of MFCs.Anaerobic sludge was inoculated in the anode compartment,and a cation exchange membrane (CEM) was adopted to separate the two chambers,while no mediator was employed in the anode and no catalyzer was used in the cathode.The maximum power density and the internal resistance were chosed as the parameters to compare the power generation of the MFCs,which had different cathode areas and different CEM areas.The results showed:①When cathode electrode area is small,the power density increases with the increase of cathode electrode area,the internal resistance decreases with the increase of cathode electrode area,but the magnitude of both gradually decreases; when the two reaches maximum value,with the increase of the cathode electrode area,the power density decreases and the resistance increases; The maximum power density gained in the experiment was 27.36 mW/m2 and the minimum internal resistance was 1.84 kΩ with a cathode area of 71.55 cm2.② When the area of CEM was less than that of anode electrode,the dimension of CEM was the limiting parameter to the increase of power generation.Increasing the CEM area would improve the MFCs' power output and reduce its internal resistance.When the CEM area (9.62 cm2) corresponded with the anode electrode area (8.42 cm2),MFCs had the optimal condition,which had a maximum power density of 46.1 mW/m2 and an internal resistance of 1.01 kΩ. |
