In situ production of hydrogen peroxide in a microbial fuel cell for recalcitrant wastewater treatment

BACKGROUND Microbial fuel cells ( MFCs ) offer a sustainable and energy efficient solution for in situ hydrogen peroxide ( H 2 O 2 ) production with simultaneous power generation. In MFCs , H 2 O 2 is produced as a result of two‐electron oxygen reduction at graphite cathode surface. However, due to poor catalytic properties of graphite cathode high yields of H 2 O 2 are not attained. Therefore, this study investigates the feasibility of in situ H 2 O 2 production in MFC for recalcitrant wastewater treatment. METHODOLOGY AND RESULTS In this study, a dual chamber MFC was used. A heat‐treated graphite electrode was used as cathode and Nafion‐117 as membrane. Cyclic voltammetric analysis was also performed to study the potential of heat‐treated graphite cathode for H 2 O 2 production. Experimentally, a maximum of 140 mg L −1 of H 2 O 2 was produced with simultaneous power generation of 33.52 W m −3 . Consequently, in situ Fenton oxidation experiments were performed and compared with conventional Fenton oxidation using a recalcitrant pollutant i.e. Acid Blue 113 dye. On average, 24% difference between the performance of the Fenton and in situ Fenton oxidation was observed while 42% reduction in the cost of process was obtained in the case of the in situ Fenton oxidation process. CONCLUSION The current study proved that MFC is a sustainable solution for in situ Fenton oxidation (followed by H 2 O 2 production) with less requirement of H 2 O 2 . © 2017 Society of Chemical Industry