硫酸根自由基氧化过程中卤代副产物生成机制研究

近年来，基于强氧化性硫酸根自由基(SR)的高级氧化技术(SR-AOPs)在水处理的应用得到了国内外学者的广泛关注，是一种具有发展潜力的新型氧化技术。然而，SR还可将水体中普遍存在的卤素离子氧化为活性卤素，后者可与水体中的天然有机物（NOM）反应生成有毒的卤代副产物（TOX）特别是消毒副产物(DBPs)，这成为SR在实际应用中需要关注的首要问题之一。目前，有关SR-AOPs体系中TOX及DBPs生成潜能和机理的研究还未见报道。本课题将研究卤素离子存在下不同特性的NOM在SR-AOPs体系中TOX及DBPs生成潜能，考察水质条件特别是溴离子浓度的影响，识别主要前驱物并筛选关键性影响因子；进一步利用代表性模型化合物，通过研究SR-AOPs中卤素离子存在时产物的生成、自由基物种的测定（自旋电子共振波谱法），探讨TOX及DBPs的生成机理，为确定SR-AOPs的适用范围和副产物控制提供理论依据。

In recent years, highly reactive sulfate radical（SR）-based advanced oxidation processes (SR-AOPs), which is an emerging and promising oxidation technology, have attracted great scientific and technological interest for the decontamination of waters worldwide. However, ubiquitous halide ion in water can be easily oxidized to halide radical species which can react with natural organic matter in waters to form toxic halogenated byproducts (TOX) and disinfection byproducts (DBPs) in particular, which is one of the primary issues of concern for the real water/wastewater application of SR-AOPs. To date, no information is available about the formation potential and mechanism of halogenated byproducts and DBPs by SR-AOPs. This project aims to investigate the formation potential of halogenated byproducts and DBPs of different NOM isolates by SR-AOPs in the presence of halide ion. The effect of water quality conditions especially concentration of bromide ion on the formation of halogenated byproducts will be evaluated. The correlation between the characteristics of NOM and the yield of halogenated byproducts will be examined. The major precursor of TOX and DBPs and key influencing factors will be identified. The formation mechanism of halogenated byproducts and DBPs will be explored through the investigation of byproduct formation of typical model compounds by SR-AOPs in the presence of halide ion and analysis of radical species by electron spin resonance. The results of this project can provide the scientific foundation for the application scope of SR-AOPs and the control of byproducts.