Hybrid microbial fuel cell–Photo-Fenton system for treatment and energy recovery from textile wastewater

Abstract Textile wastewater poses significant environmental challenges due to high concentrations of organic matter, nitrogen, phosphorus, and persistent pollutants. Innovative and sustainable treatment technologies are crucial to mitigate these issues while minimising energy consumption and enhancing resource recovery. This study investigated a hybrid wastewater treatment system integrating a dual-chamber microbial fuel cell (MFC) with a Photo-Fenton advanced oxidation process (AOP). Continuous flow experiments were conducted at a laboratory scale using graphite felt electrodes and a high-organic-load acclimated microbial consortium. The hybrid system demonstrated high removal efficiencies: chemical oxygen demand (COD) (92.3%), biochemical oxygen demand (BOD) (95.1%), total nitrogen (TN) (73.8%), and total phosphorus (TP) (81.6%), alongside significant energy recovery (342 mW/m 2 peak power density). Notably, the MFC stage achieved dye degradation of 58.7%, highlighting its capability in preliminary pollutant remediation. Subsequent AOP treatment further reduced dye concentrations to below detection limits (< 0.5 mg/L), achieving high degradation efficiency exceeding 98%. Energy metrics revealed a stable electrochemical performance with a voltage output of 0.51 ± 0.03 V and a modest Coulombic efficiency (CE) of 18.4%, suitable for real-world industrial applications. Microbial community analysis indicated significant shifts in diversity and functionality across treatment stages, underscoring their role in pollutant degradation and system performance enhancement. This integrated MFC–Photo-Fenton system not only offers efficient wastewater treatment and energy recovery but also represents a sustainable approach to addressing complex textile effluents. These findings provide valuable insights into advancing hybrid biological–chemical processes for decentralised wastewater treatment in industrial settings.