Comparative assessment of electricity generation and wastewater treatment in a Zn–Cu dual-chamber microbial fuel cell using organic substrates

Abstract Microbial fuel cells (MFCs) offer a sustainable pathway for simultaneous wastewater treatment and bioelectricity generation. In this study, a low-cost dual-chamber MFC equipped with Zn-Cu electrodes were constructed to compare the performance of real organic wastes (kitchen, biscuit, and tea waste) with glucose and municipal wastewater. Among the tested substrates, the highest power density was found using kitchen waste, with a peak output of 144.4 mW/m² and COD removal efficiency (87%), demonstrating its suitability as a mixed organic feedstock. The glucose produced a maximum power density of 67.9 mW/m², indicating high but short-term energy generation over 15 days, while biscuit waste and tea waste exhibited moderate power generation (47.1 and 36.9 mW/m², respectively) but lower COD removal (60% and 56%). Municipal wastewater generated only a limited output (7.8 mW/m², 72% COD removal). These results highlight that heterogeneous food residues, particularly kitchen waste, can serve as efficient substrates for MFCs, offering dual benefits of energy recovery and wastewater treatment in resource-limited settings.