摘要
采用紫外光(UV)降解饮用水中含氮消毒副产物(N-DBPs)二氯乙腈(DCAN)与三氯乙腈(TCAN),研究了初始浓度、pH值和辐照强度等对UV光降解2种N-DBPs的影响.结果表明:UV可降解DCAN与TCAN,其中去除TCAN效率较高,在UV辐照2h,pH 7.70的常温条件下,质量浓度为100μg.L-1的TCAN去除率可达98.5%以上;而对100μg.L-1的DCAN,辐照6h后的去除率为97.0%;UV降解DCAN的去除率与其初始浓度正相关,TCAN的初始浓度对UV降解最终去除率几乎没有影响;pH值对UV降解2种N-DBPs的影响较小,但随pH值的增高,2种物质的降解为水解与光解的协同作用;UV辐照强度的增加有利于DCAN与TCAN的去除;自来水中余氯的存在,一定程度上可能会促进DCAN与TCAN的降解速率.
Performance of photodegraded two nitrogenous disinfection by-products（N-DBPs）,dichloroacetonitrile（DCAN） and tichloroacetonitrile（TCAN）,in drinking water by ultraviolet（UV） irradiation was investigated.The effects of the initial DCAN and TCAN concentrations,solution pH,irradiation intensity and water quality on the corresponding photodegradation efficiency were studied.DCAN and TCAN could be photodegraded by UV irradiation.Removal efficiency of TCAN was higher than DCAN.With the initial concentration of 100 μg·L-1,the removal rate of TCAN could achieve 98.5% after 2 h of UV irradiation and removal efficiency of DCAN was 97.0% after 6 h of UV irradiation at room temperature and pH of 7.70.Removal efficiency of DCAN increased with its initial concentration,but the effect of initial TCAN concentration on photodecomposition of TCAN was not remarkable.Increased pH improved the removal of DCAN and TCAN,which was directly caused by the synergy of hydrolysis and photodecomposition.Increased ultraviolet irradiation intensity increased the removal efficiency of DCAN and TCAN.Water quality affected the removal of DCAN and TCAN slightly.Thereinto,residual chlorine in drinking water avail the removal of DCAN and TCAN.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第12期111-114,共4页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家科技重大专项资助项目(2008ZX07421-002)
国家高技术研究发展计划资助项目(2008AA06A412)
中国博士后科学基金资助项目(20110490073)
关键词
饮用水
含氮消毒副产物
二氯乙腈
三氯乙腈
紫外光
光降解
drinking water
nitrogenous disinfection by-products
dichloroacetonitrile
trichloroacetonitrile
ultraviolet irradiation
photodegradation
