摘要
该文构建了Fe(Ⅲ)/亚硫酸盐(Fe(Ⅲ)-S(Ⅳ))体系降解磺胺氯哒嗪(SCP)的动力学模型,探究了该体系中不同自由基单独氧化SCP的机制。通过电子自旋共振实验、无氧实验、淬灭实验和甲基苯基亚砜实验鉴别了反应过程中的活性物种,并分析其对SCP氧化的贡献。结果表明,在pH=4时,体系中的主要活性物种是SO_(4)^(·-)、SO_(5)^(·-)和·OH,贡献率分别为76.3%、22.3%和1.40%,与动力学模拟的结论基本一致。通过密度泛函理论计算了SCP的主要反应位点,结合液相质谱分析了体系中SO_(4)^(·-)和SO_(5)^(·-)单独降解SCP的中间产物,并提出相应的反应路径,完善了S(Ⅳ)体系中不同硫氧自由基单独氧化污染物的降解途径和作用机制。
Kinetics simulation model for the degradation of sulfachlorpyridazine(SCP)in Fe(Ⅲ)/sulfite(Fe(Ⅲ)-S(Ⅳ))system was established,and the reaction mechanism of different radicals in this system was also investigated.The reactive species were identified by electron spin resonance experiments,anaerobic experiment,quenching experiments and PMSO experiment,and their contributions were also analyzed.It was showed that the main reactive species at pH=4 in the system were SO_(4)^(•-),SO_(5)^(•-)and·OH,and the contribution of each radicals were 76.3%,22.3%and 1.40%,respectively.The results were consistent with the kinetics simulation.Subsequently,the main reaction sites of SCP were calculated by density functional theory,and the intermediate products of SCP degradation by SO_(4)^(•-)or SO_(5)^(•-)were analyzed by LC-MS.The degradation pathways and mechanisms of different radicals in S(Ⅳ)system were improved and verified.
作者
张弈辉
王文宇
吴峰
周丹娜
ZHANG Yihui;WANG Wenyu;WU Feng;ZHOU Danna(Hubei Key Laboratory of Biomass Resource Chemistry and Environmental Biotechnology,School of Resources and Environmental Science,Wuhan University,Wuhan 430079,China;Faculty of Materials Science and Chemistry,China University of Geosciences,Wuhan 430074,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2024年第7期139-147,共9页
Environmental Science & Technology
基金
国家自然科学基金项目(21876160)。
