阴极电极面积和膜面积对H型MFCs产电能力的影响

Effect of Cathode Electrode and Cation Exchange Membrane Areas on Electricity Production of H-type MFCs

以生活污水为底物,碳棒作电极,构建H型瓶式微生物燃料电池(microbial fuel cells,MFCs),研究了阴极电极面积和膜面积对电池产电能力的影响.阳极以厌氧污泥作接种体,两室分隔物使用阳离子交换膜(cation exchange membrane,CEM),阳极不使用中介体,阴极使用无催化剂的普通碳电极.采用几种不同的阴极面积和阳离子交换膜面积,以最大功率密度和内阻等作为比较参数,比较其产电性能.结果表明:①阴极电极面积较小时,功率密度随其增加而增大,内阻随其增加而减小,但两者的变化幅度均逐渐减小;当两者达到极值后,随着阴极电极面积的增加,功率密度值逐渐减小,内阻增大;当阴极电极面积为71.55 cm2时,最大功率密度达到最大值为27.36 mW/m2,内阻达到最小值为1.84 kΩ;②CEM面积小于阳极电极面积时,CEM尺寸是MFCs产电能力提高的限制性因素,增大CEM面积可以显著提高MFCs功率输出,降低系统内阻,电池产电性能最优的条件是CEM面积(9.62 cm2)与阳极电极面积(8.42 cm2)相当,得到的最大功率密度为46.1 mW/m2,内阻为1.01 kΩ.

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.