摘要
高级氧化技术是一种以产生羟基自由基(·OH)和硫酸根自由基(SO_(4)^(−)·)来降解环境有机污染物的技术.近年来,通过活化过一硫酸盐(peroxymonosulfate,PMS)而产生SO_(4)^(−)·的高级氧化技术受到了广泛关注.与基于·OH的传统高级氧化技术相比,基于SO_(4)^(−)·的高级氧化技术具有氧化还原电位高、半衰期长、适用pH范围广和对污染物反应快速等优点.本文从活化PMS方法的特点和性质出发,对目前活化PMS技术降解环境有机污染物的主要方法和活化机理进行了论述,活化方法包括过渡金属活化(均相和非均相)、碳质材料活化、碱性活化、热活化、辐射活化、电解活化等,活化PMS的机制是通过活化方法使其分子结构中的O—O键发生断裂,从而使PMS分解形成SO_(4)^(−)·或其他的活性物质.此外,分析了活化PMS降解环境有机污染物的主要影响因素,其中影响均相系统PMS活化的因素包括过渡金属剂量、pH和水中阴离子等,过量的PMS和过渡金属可能成为SO_(4)^(−)·的抑制剂,pH不仅对氧化剂分解产生自由基起着关键作用,还影响过渡金属种类的形成及其与氧化剂反应的有效性,而水中阴离子会与有机化合物竞争和SO_(4)^(−)·发生反应.最后,提出未来研究重点应在开发稳定高效活化PMS的金属氧化物、碳质材料,以及使用多种处理技术协同作用上,同时应加强对活化PMS技术降解有机污染物体系的降解产物和毒性分析的研究.
Advanced oxidation processes are promising technologies that can generate hydroxyl radicals and sulfate radicals to degrade organic environmental pollutants.In recent years,the advanced oxidation processes that generate sulfate radicals by activating peroxymonosulfate(PMS)have received widespread attention.Compared with the traditional advanced oxidation processes based on hydroxyl radicals,sulfate radicals-based advanced oxidation processes have the following advantages:high redox potential,long half-life,wide applicable pH range and rapid reaction to pollutants.This paper summarizes the main PMS activation methods and the activation mechanism based on the characteristics and properties of PMS activation.The activation methods of PMS can occur by various methods,including transition metal activation(homogeneous and heterogeneous),carbon material activation,alkaline activation,thermal activation,radiation activation,electrolytic activation,etc.The activation mechanism of PMS is to break the O—O bond in the molecular structure,which leads to the decomposition of PMS to form sulfate radicals or other active substances.In addition,the main factors influencing the activation process of PMS to remove organic pollutants were analyzed.The factors affecting the activation of PMS in homogeneou systems include the dosage of transition metals,pH,and the presence of anions in the water.An excess of PMS and transition metals can inhibit sulfate radicals generation.The pH value not only plays a key role in the decomposition of oxidants into free radicals,but also affects the formation of transition metal species and the effectiveness of their reactions with oxidants.The anions present in the water will compete with the organic compounds and react with the sulfate radicals.Finally,the future research focus should be on the development of metal oxides and carbon materials for stable and efficient activation of PMS,as well as the synergistic effect of multiple treatment technologies.Meanwhile,the degradation products and toxicity analysis of activated PMS technology to degrade organic pollutants should be strengthened.
作者
代朝猛
刘仟
段艳平
刘曙光
涂耀仁
DAI Chaomeng;LIU Qian;DUAN Yanping;LIU Shuguang;TU Yaojen(College of Civil Engineering,Tongji University,Shanghai 200092,China;School of Environment and Geography,Shanghai Normal University,Shanghai 200234,China;Yangtze River Delta Urban Wetland Ecosystem National Field Observation and Research Station,Shanghai 200234,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2022年第1期141-149,共9页
Research of Environmental Sciences
基金
国家重点研发计划项目(No.2019YFE0114900)
国家自然科学基金项目(No.42077175)。
