Mezyk Stephen P, Rogalski Maya H, Dang Anh N, Bartels David M, Hardison D Ransom, Cooper William J
Department of Chemistry and Biochemistry, California State University at Long Beach, 1250 N. Bellflower Blvd., Long Beach, California 90840, United States.
Radiation Research Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States.
ACS ES T Water. 2025 May 13;5(6):3316-3324. doi: 10.1021/acsestwater.5c00134. eCollection 2025 Jun 13.
Haloacetonitriles (HANs) are important drinking water disinfection byproducts formed through the chlorination and chloramination of amino acids. Although HAN concentrations in treated water are usually lower than trihalomethanes, they are still of major concern due to their higher cyto- and genotoxicity. HANs undergo chemical transformations by hydrolysis on the hour to week time scales; however, for possible direct water reuse situations, their active removal using advanced oxidation/reduction processes (AO/RPs) may be required. We report here our systematic kinetic study of the four major AO/RP radiolysis species, oxidizing hydroxyl (·OH) and sulfate (SO ) radicals and reducing hydrated electron (e ) and hydrogen atoms (H) with five HANs (mono-, di-, and trichloroacetonitriles and mono- and dibromoacetonitriles) in water measured using electron pulse radiolysis techniques. At ambient temperatures and pH 1-7, significant reactivity was found for e ( = (1-5) × 10 M s) and H atoms ( = (1 - 40 × 10 M s), but only minimal oxidation by OH ( = (0.6-10) × 10 M s) and SO ( = (0.2-4) × 10 M s) occurred. These data suggest that the large-scale AO/RP treatment of these contaminants will be effective for deaerated reducing systems, where the reductive electron-induced degradation of HANs will occur.
卤代乙腈（HANs）是通过氨基酸的氯化和氯胺化形成的重要饮用水消毒副产物。尽管处理后水中的HAN浓度通常低于三卤甲烷，但由于其更高的细胞毒性和遗传毒性，它们仍然是主要关注的问题。HANs在数小时到数周的时间尺度上通过水解进行化学转化；然而，对于可能的直接水再利用情况，可能需要使用高级氧化/还原工艺（AO/RPs）对其进行有效去除。我们在此报告了我们使用电子脉冲辐解技术对水中五种HANs（一氯、二氯和三氯乙腈以及一溴和二溴乙腈）与四种主要AO/RP辐解物种（氧化羟基（·OH）和硫酸根（SO ）自由基以及还原水合电子（e ）和氢原子（H））进行的系统动力学研究。在环境温度和pH值为1 - 7的条件下，发现e （ = (1 - 5) × 10 M s）和H原子（ = (1 - 40 × 10 M s)）具有显著的反应活性，但OH（ = (0.6 - 10) × 10 M s）和SO （ = (0.2 - 4) × 10 M s）的氧化作用极小。这些数据表明，对这些污染物进行大规模的AO/RP处理对于脱气还原系统将是有效的，在该系统中HANs会发生由还原电子诱导的降解。
