水体冻结过程中卤乙酸前体物在水-冰体系中的分配研究  

Ratio of haloacetic acids precursor in water-ice system during the freezing processes of water

作　　者：薛爽[1] 陈静[1] 铁梅[1] 惠秀娟[1] 张丽娜[1] 张营[1] 

机构地区：[1]辽宁大学环境学院,辽宁沈阳110036

出　　处：《中国环境科学》2014年第11期2773-2780,共8页China Environmental Science

基　　金：国家自然科学基金(21107039);辽宁省教育厅项目(L2011002);辽宁省科学技术计划项目(2011230009)

摘　　要：通过室内模拟试验,研究了水体冻结过程中,水体中溶解性有机物(DOM)和卤乙酸前体物在水-冰体系中的分配规律.按照DOM在XAD树脂上的吸附特性将其分为5个部分:疏水性有机酸(HPO-A),疏水性中性有机物(HPO-N),过渡亲水性有机酸(TPI-A),过渡亲水性中性有机物(TPI-N)和亲水性有机物(HPI).结果表明:在水体冻结过程中,5种DOM组分在水相中的DOC浓度均随冷冻时间的增长而增加,呈现冷冻浓缩效应.与溶解性有机碳(DOC)所表征的整体有机物相比,5种DOM组分中的卤乙酸(HAAs)前体物更倾向于停留在水相中浓缩.在5种DOM组分中,HPI是主要的HAAs前体物.5种DOM组分在未冻结水中的UV-254与HAAFP均表现出一定相关性,其中HPO-A,TPI-A和HPI的UV-254与HAAFP达到极显著水平.然而在融冰水中,这5种DOM组分的UV-254与HAAFP的相关性均不显著.It was studied the partition of dissolved organic matter （DOM） fractions and haloacetic acids （HAAs） precursors in water-ice system during the freezing processes of water by the indoor simulating tests. DOM was fractionated using XAD resins into five fractions： hydrophobic acid （HPO-A）, hydrophobic neutral （HPO-N）, transphilic acid （TPI-A）, transphilic neutral （TPI-N） and hydrophilic fraction （HPI）. The results showed that the freezing rate of water samples containing acid fractions wove higher than samples containing neutral fractions. DOC concentrations for five DOM fractions in liquid phase increased with freezing time, presenting the freeze-concentration effect, during the freezing processes of water. HAAs precursors were more liable to be concentrated in liquid phase, as compared with the bulk DOM represented by dissolved organic carbon （DOC）. HPI, among the five DOM fractions, was the main HAAs precursors. There was significant correlation between UV-254 and HAAFP for five DOM fractions in unfrozen liquid samples. Moreover, for HPO-A, TPI-A and HPI achieved very significant linear correlation. However, there was no significant correlation between UV-254 and HAAFP for all five DOM fractions in melted ice samples.

关 键 词：冻结 溶解性有机物 分级 紫外光谱 卤乙酸前体物 

分 类 号：X703[环境科学与工程—环境工程] TU992[建筑科学—市政工程]