Catalysing holistic wastewater treatment, electricity generation, and emerging contaminant removal in a pre-pilot Fenton-microbial fuel cell

Abstract

Fenton-based microbial fuel cells (MFCs) offer a sustainable option for energy production, wastewater treatment, and contaminant removal. In this investigation, a novel 2.5 L dual-chamber cost-effective ceramic membrane-separated pre-pilot Fenton-MFC was designed and the cathode was catalysed with rGO–Co₃O₄. The rGO–Co₃O₄ catalysed Fenton-MFC demonstrated superior electrocatalytic performance and durability, achieving a maximum current density of 258.33 mA m⁻². Additionally, the Fenton-MFC facilitated the in situ production of 218 ± 4 mg L⁻¹ hydrogen peroxide. This hydrogen peroxide production enabled the degradation of congo red (89.41 ± 3.8%), sodium dodecyl sulphate (72 ± 0.7%), and tetracycline (74 ± 1.6%) within 150 min without addition of supporting electrolytes such as persulphate or NaCl. Moreover, the anodic effluent was also treated in a cathodic chamber, resulting in an effluent with chemical oxygen demand (COD) of 162 ± 4 mg L⁻¹ and zero MPN (initial COD: 3000 mg L⁻¹). Finally, a gate-to-gate life cycle assessment was conducted to identify the life cycle impacts of the proposed system. The results of this integrated approach enhance the energy efficiency of the MFC system while addressing environmental concerns related to pollutant degradation, thus providing an innovative prospect for scaling up the Fenton-MFC technology.