Performance and application of microbial fuel cells with sodium alginate/agar/activated carbon composite as efficient biocompatible anode

Microbial fuel cells (MFCs) are a potential biotechnology for simultaneous degradation of organic wastewater and power generation. In this paper, a biocompatible composite is constructed around a copper mesh with sodium alginate/agar and activated carbon (CM-SA/AC) and acts as an efficient anode for MFCs after being microbe immobilized. The power performance of the MFC with CM-SA/AC anode is investigated. The results show that the addition of activated carbon is conducive to the immobilization of bacteria on CM-SA/AC anode and fast start-up of MFCs. The power density reaches 1088.6 mW/m(2), which is 2.03 times and 1.75 times that of CM-SA (without activated carbon) anode and carbon felt anode, respectively. In case of a candied wastewater treatment, the MFC with immobilized CM-SA/AC anode exhibits a much higher power density (724.5 mW/m(2)) than that with carbon felt anode (145.0 mW/m(2)), together with a longer stabilization time and a smaller charge-transfer resistance. The total removal rate of chemical oxygen demand (COD) reaches 79.4 +/- 0.65%. The present study will facilitate the development of inexpensive and biocompatible anodes to facilitate the application of MFCs in wastewater treatment.