Carbon source-augmented aerobic microbial fuel cell: performance and mechanisms in simultaneous tobacco wastewater treatment and electricity generation

This study investigated the feasibility of tobacco wastewater treatment and simultaneously generating electricity using microbial fuel cells (MFCs) under aerobic conditions. A series of dual-chamber MFCs inoculated with tobacco wastewater were constructed, and the effects of an extra carbon source (glucose and acetate) and no additional carbon source in tobacco wastewater on MFC performance were compared. MFCs with extra carbon sources exhibited significantly superior electricity generation performance, achieving maximum voltages of 0.70 V (glucose) and 0.68 V (acetate) and maximum power densities of 605.79 mW m⁻² and 653.55 mW m⁻², respectively. The COD removal rates of tobacco wastewater in MFCs with glucose and acetate reached 72.75% and 74.71%, respectively, which were significantly higher than that of the MFC with raw tobacco wastewater (29.35%). Microbial community analysis revealed that the addition of carbon sources markedly increased the abundance of electroactive bacteria (e.g., Trichococcus and Enterococcus) while reducing anode microbial diversity, indicating the dominance of electrochemically active bacteria. This study validates the potential of aerobic MFCs for treating tobacco wastewater and provides theoretical insights for optimizing carbon source selection and microbial community regulation.