Application of a Halophilic Consortium for Saline Phenol Wastewater Treatment and Bioelectricity Generation in Microbial Fuel Cells: An AI-Driven Evaluation
Abstract
High organic pollutant load and salinity pose major challenges for the biological treatment of industrial wastewater. This study evaluated an air-cathode microbial fuel cell (AC-MFC) inoculated with halophilic microorganisms for the simultaneous treatment of phenol-contaminated saline industrial wastewater and bioelectricity generation. The AC-MFC was operated at organic loads (OLs) of 1.2, 2.5, 3.2, 4.8, 6.2 and 8.6 g chemical oxygen demand (COD)/L, with optimum performance at 6.2 g COD/L. In optimal conditions, the system achieved a maximum voltage of 803 mV, power density of 460.6 mW/m2, current density of 573.6 mA/m2, and total and soluble COD removal efficiencies of 90% and 89%, respectively. Complete phenol degradation was achieved within 8 days. High-throughput sequencing revealed dominant halophilic taxa, including Ochrobactrum, Marinobacter, Bacillus and Stenotrophomonas, which may contribute to pollutant degradation and extracellular electron transfer. A Random Forest regression model implemented using Python/scikit-learn was further developed using OL and operational time as input variables to predict treatment and electrochemical performance. The model identified 6.2 gCOD/L as the optimum OL, consistent with the experimental results. Overall, inoculation of halophilic consortium coupled with AC-MFC technology demonstrates potential for simultaneous treatment of saline phenolic wastewater and bioelectricity generation, while artificial intelligence provides a useful tool for process optimization.