School of Environment and Energy, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510640, China.
School of Environment and Energy, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510640, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, China; School of Environment and Energy, State Key Laboratory of Pulp and Paper, South China University of Technology, Guangzhou, Guangzhou, 510006, China.
Chemosphere. 2021 Jun;272:129629. doi: 10.1016/j.chemosphere.2021.129629. Epub 2021 Jan 15.
Advanced oxidation processes (AOPs) based on persulfate (PS) has attracted great attention due to its high efficiency for degradation of organic pollutants. Manganese-based materials have been considered as the desirable catalysts for in-situ chemical oxidation since they are abundant in the earth's crust and environment-friendly. In this study, manganese oxyhydroxide (MnOOH) was used as an activator for PS to degrade p-chloroaniline (PCA) from wastewater. The effects of MnOOH dosage, PS dosage and initial pH on PCA degradation performance were studied. Experimental results showed that PCA degradation efficiency was enhanced by higher MnOOH and PS addition, and the degradation efficiency was slightly inhibited as the initial pH increased from 3 to 9. MnOOH showed excellent stability and reusability when used as the activator of PS. In addition, a comprehensive study was conducted to determine the PS activation mechanism. The results revealed that PS activation by MnOOH followed a nonradical mechanism. No O was generated, and the main active substance in the reaction was the activated PS molecule on the surface of MnOOH. The hydroxyl group on the catalyst surface acted as a bridge connecting PS and the catalyst, leading to the activation of PS. The intermediates during PCA degradation were also analyzed, and three possible degradation pathways of PCA were proposed. This study expects to deepen the understanding of the PS activation mechanism by manganese oxide, and provides technical support for the practical application of AOPs of manganese-based materials for wastewater treatment.
基于过硫酸盐（PS）的高级氧化工艺（AOPs）因其高效降解有机污染物而受到广泛关注。由于锰基材料在地壳和环境中丰富且环保，因此被认为是原位化学氧化的理想催化剂。在这项研究中，使用锰氧氢氧化物（MnOOH）作为 PS 的活化剂来降解废水中的对氯苯胺（PCA）。研究了 MnOOH 用量、PS 用量和初始 pH 值对 PCA 降解性能的影响。实验结果表明，较高的 MnOOH 和 PS 加量可以提高 PCA 的降解效率，而初始 pH 值从 3 增加到 9 时，降解效率略有抑制。MnOOH 用作 PS 的活化剂时表现出优异的稳定性和可重复使用性。此外，还进行了综合研究以确定 PS 的活化机制。结果表明，MnOOH 对 PS 的活化遵循非自由基机制。没有生成 O，反应中的主要活性物质是 MnOOH 表面上的活化 PS 分子。催化剂表面的羟基作为连接 PS 和催化剂的桥梁，导致 PS 活化。还分析了 PCA 降解过程中的中间体，并提出了 PCA 的三种可能降解途径。本研究期望加深对锰氧化物活化 PS 机制的理解，并为基于锰基材料的 AOPs 处理废水的实际应用提供技术支持。
