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.

Automated summary

Microbial fuel cells (MFCs) show potential for simultaneous organic wastewater degradation and power generation. This study focuses on a biocompatible composite, CM-SA/AC, as an efficient anode for MFCs. Results indicate that the addition of activated carbon promotes bacterial immobilization and fast start-up of MFCs. In terms of candied wastewater treatment, the MFC with immobilized CM-SA/AC anode exhibits higher power density, longer stabilization time, and smaller charge-transfer resistance compared to MFCs with carbon felt anode. The total removal rate of chemical oxygen demand reaches 79.4%. This study contributes to the development of inexpensive and biocompatible anodes for MFCs in wastewater treatment.