高盐环境苯酚氧化降解的氯转移/累积/释放机制研究

Chlorinated aromatic compounds (CACs) is a kind of widely distributed, stable and carcinogenic pollutant, however, its formation mechanism in water treatment (especially for saline wastewater) was still unclear. Chloride ions are not only one of the major degradation byproducts of CACs, but also a potential chlorine atom pool for CACs formation. To couple pollutant decontamination and chlorine transfer/accumulation/release together, using a typical aromatic compound and a common degradation intermediate-phenol as target pollutant and latent chlorine carrier, this project aims to center on the Cl(inorg)→Cl(org)→Cl(inorg) transformation in saline wastewater treatment by advanced oxidation processes by applying kinetic modeling and 13C labeling/37Cl isotope trace methods, and to investigate the kinetics of chlorine transfer/accumulation/release among chlorine carriers during phenol oxidative degradation. This project will reveal their involved mechanisms in saline waters containing reactive radical oxidants, phenol and its degradation/chlorination intermediates, chloride and oxygen, and their resulting chlorine transfer/accumulation/release and de novo chlorine transfer mechanisms. Therefore, this project is expected to provide important information for exploring new source and sink of toxic CACs in saline wastewater treatment.

氯代芳香族化合物(CACs)是一种分布广、稳定性高、致癌性强的环境污染物，但其在水处理尤其在高盐废水中的生成机制至今尚不明确。无机氯离子既是CACs降解矿化的主要产物，又是含盐废水处理中CACs生成的氯原子来源。本项目拟将污染物氧化降解历程和氯转移/累积/释放过程的耦合效应作为主要研究目标，以典型的芳香族化合物和CACs常见降解产物-苯酚为研究对象和潜在氯载体，结合动力学软件模拟研究和13C标记及37Cl示踪方法，以高级氧化技术处理高盐废水有机物时可能发生的无机氯→有机氯→无机氯过程为切入点，研究高盐废水中苯酚氧化降解引发的氯在各种氯载体中转移/累积/释放的动力学。试图揭示活性自由基氧化剂、苯酚及其氯代/降解产物、氯和氧气等物种的相互作用原理及其引发的氯转移/累积/释放与二次转移的氯循环机制，为探知氯代有毒有机污染物在废水处理中新的"源"和"汇"提供有价值的参考。

氯代芳香族化合物(CACs)在环境中分布广, 稳定性高且致癌性强,但其在水处理尤其在高盐废水中的生成机制至今尚不明确。无机氯离子既是CACs降解矿化的主要产物，又是含盐废水处理中新生成的CACs的氯原子来源。项目将CACs氧化降解与氯转移/累积/释放过程的耦合效应为主要研究目标，构建了多种以空穴、超氧自由基、羟基自由基和硫酸根自由基、单线态氧等为主要氧化活性物种的高级氧化降解体系，深入研究了羟基自由基和硫酸根自由基主导的有机物降解体系的动力学过程和降解途径，揭示了高盐废水中芳香族化合物(比如染料、氯酚)及其次级产物(比如邻苯二甲酸)氧化降解过程中发生的无机氯→有机氯→无机氯的转化机制。项目成果为探知氯代有毒有机污染物在废水处理中新的“源”与“汇”提供了科学参考。本项目共在 <Environ. Sci. Technol.>, <Chem. Eng. J.>和<Chemosphere>等国际环境化学权期刊发表43篇SCI期刊论文, 参加国内外学术交流16次，培养博士研究生7名，培养硕士研究生12名。