A mechanism-material-matrix framework for electrochemical advanced oxidation of persistent organic pollutants in wastewater

Abstract

Persistent organic pollutants remain difficult to treat because disappearance of the parent compound can conceal incomplete mineralization, toxic intermediates, or high energy demand. This review asks when electrochemical advanced oxidation processes (EAOPs) provide defensible treatment rather than rapid analytical removal. We advance and test a mechanism-material-matrix-implementation framework: electrode and catalyst properties plus reactor geometry define the reactive-species window, while the wastewater matrix redistributes oxidant flux and changes both benefit and risk. Primary studies of anodic oxidation, electro-Fenton chemistry, active chlorine, sulfate-derived oxidants, three-dimensional cells, falling-film reactors, and reactive membranes are compared using initial concentration, removal kinetics, TOC or COD conversion, specific energy, by-product or toxicity evidence, and matrix transferability. The synthesis shows that flow-through and paired systems can combine high removal with substantial mineralization under defined conditions, whereas chloride-rich or adsorption-assisted systems can overstate performance when carbon balance and toxicity are omitted. Real-wastewater evidence further reveals trade-offs among matrix scavenging, oxyhalide formation, auxiliary energy, fouling, and durability. Four tables and nine figures convert these findings into mechanism, design, risk, and deployment criteria. The central conclusion is that EAOP performance is a system property, not an electrode property. This review is important because the framework turns heterogeneous literature into decision-ready criteria for selecting EAOPs as concentrate-destruction, pretreatment, post-treatment, or polishing stages.