Enhancing microbial fuel cell performance for sustainable distillery wastewater remediation and bioenergy recovery through cost‐effective alkaline ( <scp>KOH</scp> ) treatment of graphite electrodes

Abstract Distillery wastewater, characterized by a high organic load and complex pollutants, poses severe environmental challenges if discharged untreated. This study addresses the need for sustainable treatment methods by developing and optimizing a dual‐chamber microbial fuel cell (MFC) capable of both wastewater remediation and bioelectricity generation. Graphite electrodes were surface‐modified using potassium hydroxide (KOH) and hydrochloric acid (HCl) at varying concentrations to enhance microbial adhesion and electron transfer. Performance was evaluated through power density, chemical oxygen demand (COD) removal efficiency, and coulombic efficiency (CE). The 5 M KOH‐treated electrodes achieved the highest performance, delivering a maximum power density of 9.0 mW/cm 2 , COD removal efficiency of 87.9%, and CE of 32.1% significantly outperforming both HCl‐treated and untreated electrodes. The improvements were linked to increased surface roughness, porosity, and the presence of oxygen‐containing functional groups. These findings demonstrate that KOH modification offers a cost‐effective and efficient strategy for enhancing MFC performance, making it a promising approach for sustainability.