Optimizing Microbial Fuel Cell Efficiency Through a Designed Electrogenic Consortium to Remove Alkylbenzenes

Developing sustainable remediation strategies to biodegrade alkylbenzenes remains challenging. We have developed a microbial fuel cell (MFC) based on a novel electrogenic microbial consortium derived from mangrove sediments. The consortium was progressively acclimated to codegrade ethylbenzene and xylenes (EXs) while generating bioelectricity, achieving a maximum voltage of 520.0 ± 15.7 mV and a power density of 63.4 ± 5.3 mW m −2 . At the end of the MFC operation (120 h), the biofilm preferentially biodegraded EXs over acetate, removing 97.2 ± 1.9% Xs and 89.4 ± 7.5% ethylbenzene were observed, and sustained electric output was maintained. Electrochemical analyses revealed enhanced redox activity, reduced resistance to charge transfer, and increased electrochemically active surface area, which indicated that acclimation improved extracellular electron transfer. Microscopic, microbial and electrochemical characterizations confirmed the formation of a dense and conductive biofilm under EXs feeding, composed mainly by Acetobacterium , Pseudochrobactrum , and Acinetobacter , while simultaneously generating electricity, with H 2 as intermediate of electron transfer. Overall, the results demonstrate that microbial acclimation enhances electrochemical performance and alkylbenzene biodegradation, highlighting that MFCs are potential integrated platforms for remediating aromatic hydrocarbon while recovering energy.