铜离子对双室微生物燃料电池电能输出的影响研究

Effect of Cu^(2+) on the Power Output of Dual-chamber Microbial Fuel Cell

通过分别或同时向阳极室和阴极室添加Cu2+,借助铜在体系中的分布解析,研究了Cu2+对体系内阻及其分布、电能输出、库仑效率等的影响,以期为微生物燃料电池(microbial fuel cell,MFC)处理含铜废水的相关研究提供有益参考.结果表明,阳极添加10 mg·L-1的Cu2+会增大体系阳极反应的活化内阻及总体表观内阻,降低体系的电能输出和库仑效率,而阴极添加500 mg·L-1的Cu2+可显著降低阴极反应的活化内阻及总体表观内阻,提高体系产电效率.铜在体系中分布的研究表明,阳极室Cu2+不会向阴极室迁移扩散;当阴极添加Cu2+时,大部分被还原沉淀,另一部分因浓度梯度透过质子交换膜(proton exchange membrane,PEM)迁移扩散至阳极室(2.8%),影响产电微生物活性及系统的电能输出,仅有少部分Cu2+残留于阴极上清液中.

After addition of Cu2 ＋into the anodic and /or cathodic chamber,the effect of Cu^2 ＋on the internal resistance and its distribution,power output and coulombic efficiency of dual-chamber microbial fuel cell（ MFC） was investigated in this manuscript with the aid of analyzing the distribution of copper speciation. It could provide helpful information for correlative research on treatment of copper-containing wastewater by MFC. It showed that the addition of 10 mg·L^- 1Cu^2 ＋into the anodic chamber inhibited the microbial activity,and increased the anodic activation resistance as well as the apparent internal resistance,consequently reduced the power output and coulombic efficiency of the system. However,the addition of 500 mg·L^- 1Cu^2 ＋into the cathodic chamber significantly reduced the cathodic activation resistance as well as the apparent internal resistance,while improved the power output and the coulombic efficiency. Cu^2 ＋in the anodic chamber was not transfered into the cathodic chamber. When adding Cu^2 ＋into the cathodic chamber,it was mainly reduced and deposited on the cathodic chamber. It could also be transferred /diffused to the anodic chamber across the proton exchange membrane（ 2. 8%） because of its concentration difference,thus affecting the microbial activity and power output. Only a small amount of Cu^2 ＋remained in the supernatant of the cathodic chamber at the end of experiment.