摘要
为研究土壤中DDTs(滴滴涕)的电动迁移去除特性,以重庆市某废弃DDTs生产企业污染土壤为研究对象,采用GC-ECD分析了该土壤中DDTs的质量分数、电动迁移效果、电动去除率及试验过程中土壤理化性质改变等.结果表明:该污染场地土壤中w(p,p'-DDT)最高,w(o,p'-DDE)和w(p,p'-DDD)次之,三者分别占w(DDTs)的53.02%、23.46%和12.77%;DDTs迁移效果在192 h时基本稳定,并在3 V/cm电压梯度时迁移效果最佳,其中DDT和DDD向阳极迁移而DDE向阴极迁移,o,p'-DDE富集量最大,其c/c0〔标准化浓度,c0、c分别为电动试验前、后污染土壤中w(DDTs)〕为4.70;DDTs去除率在电动时间为192 h、电压梯度为3 V/cm时达到相对稳定,其中p,p'-DDT去除率较高,为49.7%;阴极土壤pH随电动试验时间的增加而增大,其最大值为11.63,阳极土壤表现相反,其最小值为-1.71;电流和土壤温度随电动试验时间的增加呈先增后减的趋势,其峰值均出现在第8小时.研究显示,不同DDTs异构体在电动力学作用下的迁移去除效果存在差异,并且电动过程会引起土壤理化性质改变.
To investigate the migration and removal characteristics of DDT sin pesticide-contaminated soil during electrokinetics,soil samples were collected from an abandoned pesticide production enterprise in Chongqing,China. Tests on the initial concentration of DDTs,the migration effect,the removal rate and the variations of physicochemical properties were analyzed during the electrokinetics process. The results indicated that the p,p＇-DDT concentration was maximum（ 53. 02%）,followed by 23. 46% and 12. 77% from o,p＇-DDE and p,p＇-DDD,respectively. The migration process of DDT was stable at 192 h,and the optimum voltage gradient of DDTs isomers was 3 V/cm,in which DDT and DDD migrated to the anode while DDE migrated to the cathode. o,p＇-DDE obtained optimummigration effect,whose c/c0was 4. 70. The removal rate of DDT was stable when the reaction time was 192 h,and the voltage gradient was 3V/cm,in which the optimum removal rate of p,p＇-DDT was4. 33. Cathode soil pH was increased with reaction time while the anode was opposite, whose maximum and minimum pH were11. 63 and- 1. 71. The current and temperature of the soil first increased then decreased,whose peak value appeared at the 8th hour. DDTs isomers gained different migration and removal characteristics during electrokinetics, and the electrokineticsprocess caused variations in physicochemical properties.
出处
《环境科学研究》
EI
CAS
CSSCI
CSCD
北大核心
2016年第12期1904-1912,共9页
Research of Environmental Sciences
基金
全球环境基金“履行斯德哥尔摩公约国家实施计划更新”--持久性有机污染物废物和污染场地管理战略行动计划
东北大学秦皇岛分校科技支撑项目(XNK201409)
关键词
污染土壤
DDTs异构体
电动迁移
去除率
contaminated soil
DDT isomers
electrokinetic migration
removal rate
