School of Chemical Engineering, Northeast Electric Power University, 132012, Jilin, PR China.
College of Chemistry, Jilin University, ChangChun, 130012, Jilin, PR China.
Chemosphere. 2023 Jan;311(Pt 1):136993. doi: 10.1016/j.chemosphere.2022.136993. Epub 2022 Oct 26.
Electrochemical Advanced Oxidation Process (EAOP) has been applied to the degradation of refractory pollutants in wastewater due to its strong oxidation capacity, high degradation efficiency, simple operation, and mild reaction. Among electrochemical processes, anodic oxidation (AO) is the most widely used and its mechanism is mainly divided into direct oxidation and indirect oxidation. Direct oxidation means that pollutants are oxidized at the anode by direct electron transfer. Indirect oxidation refers to the generation of active species during the electrolytic reaction, which acts on pollutants. The mechanism of AO process is controlled by many factors, including electrode type, electrocatalyst material, wastewater composition, pH, applied current and voltage levels. It is very important to explore the reaction mechanism of electrochemical treatment, which determines the efficiency of the reaction, the products of the reaction, and the extent of reaction. This paper firstly reviews the current research progress on the mechanism of AO process, and summarizes in detail the different mechanisms caused by influencing factors under common AO process. Then, strategies and methods to distinguish direct oxidation and indirect oxidation mechanisms are reviewed, such as intermediate product analysis, electrochemical test analysis, active species detection, theoretical calculation, and the limitations of these methods are analyzed. Finally some suggestions are put forward for the study of the mechanism of electrochemical advanced oxidation.
电化学高级氧化工艺（EAOP）因其强氧化能力、高降解效率、操作简单、反应温和而被应用于废水难降解污染物的降解。在电化学过程中，阳极氧化（AO）是最广泛应用的方法，其机制主要分为直接氧化和间接氧化。直接氧化是指污染物在阳极通过直接电子转移而被氧化。间接氧化是指在电解反应过程中产生的活性物质作用于污染物。AO 工艺的机制受许多因素的控制，包括电极类型、电催化剂材料、废水成分、pH 值、施加的电流和电压水平。探索电化学处理的反应机制非常重要，因为它决定了反应的效率、反应的产物和反应的程度。本文首先综述了 AO 工艺机制的研究现状，详细总结了常见 AO 工艺下，影响因素引起的不同机制。然后，综述了区分直接氧化和间接氧化机制的策略和方法，如中间产物分析、电化学测试分析、活性物质检测、理论计算，并分析了这些方法的局限性。最后，对电化学高级氧化的机制研究提出了一些建议。
