Performance evaluation of microbial fuel cell using a radiation synthesized low density polyethylene-grafted-poly (glycidyl methacrylate-co-vinyl acetate) as a proton exchange membrane.

The present work focuses on the synthesis of a proton exchange membrane to be assembled in a microbial fuel cell (MFC) for simultaneous bioelectricity production and domestic wastewater treatment. The indigenous membrane was prepared by ionizing irradiation-induced graft copolymerization of glycidyl methacrylate (GMA) and vinyl acetate (VAc) onto low-density polyethylene and subsequently, the prepared grafted sheets were sulfonated via epoxy ring-opening of PGMA moieties. Parameters affecting the grafting degree were investigated and the prepared membranes were characterized by investigating their structural, thermal, mechanical, and electrical properties. Some physicochemical characteristics including ion exchange capacity, sulfonation density, and proton conductivity were also evaluated. The data confirmed the success of the preparation protocol to obtain a suitable membrane for the proposed application. Moreover, the performance of the assembled MFC was thoroughly investigated through the evaluation of its electrochemical behaviour including cyclic voltammetry, electrochemical impedance spectroscopy, columbic efficiency, and wastewater treatment capability. The sulfonated LDPE-g-P(GMA-co-VAc) membrane of 80% grafting degree shows substantial removal of chemical oxygen demand up to about 90% with columbic efficiency of 10.1%, columbic recovery of 8.7%, rate of energy harvest of 2.1 C/h and power density of 2.72 W m⁻². However, the use of 10 mM of KMnO₄ as electron acceptor drastically increase the harvested power density to reach 356.4 W m⁻² [ABSTRACT FROM AUTHOR]