Electrocatalytic Oxidation as an Effective Pretreatment for Ultrafiltration Fouling Control: Modulation of EfOM Characteristics and Fouling Pathways

Ultrafiltration membranes are widely used in wastewater reuse systems, but membrane fouling caused by effluent organic matter (EfOM) remains a major limitation. In this study, electrocatalytic oxidation (EO) was applied as a pretreatment strategy to regulate EfOM properties and alleviate UF membrane fouling. The effects of EO pretreatment at different current densities on membrane performance, organic matter transformation, and fouling mechanisms were systematically investigated. The results demonstrated that EO significantly enhanced flux stability and fouling reversibility with different current densities. These improvements were associated with changes in EfOM characteristics after EO treatment, including decreased DOC and UV254 values, a shift toward lower-molecular-weight fractions, and variations in fluorescent organic components. Fouling model analysis revealed that EO pretreatment shifted the dominant fouling mechanism from cake layer formation toward pore-blocking process. This study provides insights into EO-assisted fouling control and highlights its potential as an effective pretreatment approach for improving UF performance.