Electrogenic bacteria in microbial fuel cells: innovative approaches to sustainable wastewater treatment and bioelectricity production

Abstract

Microbial fuel cells (MFCs) offer a promising solution to address contemporary issues such as water scarcity, pollution, high electricity costs, and reliance on fossil fuels. By utilizing exoelectrogenic bacteria, MFCs can simultaneously purify water and generate electricity. This study investigated the potential for electricity production and wastewater treatment using exoelectrogenic bacteria isolated from urban wastewater in Kerman City. A two-chamber MFC with a 500 ml volume and a KCl salt bridge for proton transfer was employed. The microbial community effectively reduced chemical oxygen demand (COD) and biological oxygen demand (BOD) by 99% and 63%, respectively, and removed heavy metals from the wastewater. The highest voltage and current generated from the effluent were 330 mV and 1.825 mA, respectively. Among the 28 identified bacterial strains, five (Shewanella sp., Lysinibacillus sp., Bacillus sp., Enterobacter sp., and Acinetobacter sp.) were selected for further study. Shewanella sp. produced the highest voltage and current, reaching 230 mV and 0.016 mA, respectively. These findings underscore the significant potential of exoelectrogenic bacteria in advancing MFC technology for sustainable wastewater treatment and energy production.