• 关键词：水合电子  亚硫酸盐/紫外  卤代有机物  光解  脱卤

• 基金项目：国家自然科学基金（No.21307057）

• 孙培德
• 浙江工商大学环境科学与工程学院, 杭州 310012

• 朱孟驹
• 浙江工商大学环境科学与工程学院, 杭州 310012

• 李旭春
• 浙江工商大学环境科学与工程学院, 杭州 310012

• 马军
• 哈尔滨工业大学市政环境工程学院, 哈尔滨 150090

• 余可儿
• 浙江工商大学环境科学与工程学院, 杭州 310012

• 摘要：水合电子（e_aq^-）是已知活性最强的还原物种之一.基于SO₃^2-受紫外光激发活化会释放e_aq^-的性质，提出了SO₃^2-/UV高级还原体系，用于降解稳定污染物.以7种卤乙酸为目标物，从卤素取代种类、卤代程度、实际水质本底影响等角度，考察了该体系对毒性卤代有机物（HOCs）的降解及脱卤效能，并探讨了相关机理.结果表明：HOCs的降解至少有直接光解和e_aq^-还原两条途径.卤素取代种类与卤化程度决定了HOCs的直接光解特性，其速率随氯、溴、碘取代顺序及卤化程度的增加而加快.SO₃^2-/UV体系显著提高了HOCs的降解及脱卤效率；对于直接光解慢的HOCs，其降解与脱卤主要由e_aq^-还原引起.SO₃^2-/UV体系在两种地表水质本底下仍具有较高的脱卤效能.

• Abstract：Hydrated electron(e_aq^-) is one of the most reactive reducing species. Based on the production of e_aq^- from the excitation of sulfite by UV irradiation, a sulfite/UV advanced reduction process was proposed for removal of recalcitrant contaminants. The reduction efficiency of recalcitrant halogenated organic compounds (HOCs) by the sulfite/UV system was assessed, by choosing seven haloacetic acids as the target compounds. The influence of substituted halogen type, halogenation degree, and realistic surface water matrix were investigated. Results indicate that the HOCs degradation proceeded via at least two pathways, including direct photolysis and e_aq^--induced reduction. Chemical structure of HOCs determined the efficiency of direct photolysis following the ascending order of Cl^- - - and halogenation degree of HOCs. The reduction by e_aq^- made major contributions to HOCs dehalogenation having relatively slow direct photolysis kinetics. The mechanism was further discussed. The system was also effective in dehalogenation of HOCs in realistic surface water.

• Key words：hydrated electron  sulfite/UV system  halogenated organic compounds  photolysis  dehalogenation

• 
  摘要点击次数： 1165 全文下载次数： 3112