微米Cu／Fe对污染土壤洗脱液中有机氯农药的降解

以表面活性剂TritonX-100（TX-100）为洗脱剂，某有机氯农药（organochlorinepesticides，OCPs）污染场地土壤为对象，七氯、氯丹和灭蚁灵为目标污染物，研究微米Cu／Fe双金属对污染土壤洗脱液中OCPs的降解效果。考察了洗脱液中OCPs初始浓度、洗脱液pH值、微米零价铁加入量和cu负载量对Cu／Fe去除OCPs效果的影响。结果表明，微米Cu／Fe可以有效的去除土壤洗脱液中目标污染物。当微米零价铁加入量为1．0g（25g／L），cu负载量为1．0％，洗脱液pH值为6．89时，Cu／Fe对2号土壤洗脱液中七氯、γ-氯丹、α-氯丹和灭蚁灵的去除效果最好，去除率分别为100．0％、99．3％、80．8％和71．1％。洗脱液中OCPs初始浓度越低，微米零价铁加入量越大，Cu／Fe对OCPs去除率越高；偏酸性条件有利于Cu／Fe对γ-氯丹和灭蚁灵的去除，而α-氯丹在中性条件下去除效果最好；1号土壤和2号土壤洗脱液的最佳铜负载量分别为2．O％和1．0％。

Degradation of organochlorine pesticides in soil washing effluent by micro Cu/Fe bimetallic particles

This study investigated the removal efficiency of organochlorine pesticides （OCPs）, including heptachlor, chlordane and mirex, from soil washing effluent by micro Cu/Fe bimetallic particles. Nonionic sur- factant triton X-100 （TX-100） was used as the solubilizing agent. Various factors including initial concentration of OCPs, solution pH, the amount of added micro Fe0 and Cu loading were examined. Batch experiments demon- strated that micro Cu/Fe could effectively remove OCPs from the washing effluent. The greatest reduction of OCPs from the washing effluent of soil No. 2 was achieved under the application of 1.0 g （25 g/L） micro Fe0 with 1.0% Cu loading, and solution pH of 6.89. The maximum removal rate of heptachlor, γ-chlordane, α- chlordane and mirex were 100.0% , 99.3% , 80.8% and 71.1% , respectively. Moreover, lower initial concen- tration of OCPs and higher dosage of micro Fe＋ led to higher degradation rate of OCPs. Slightly acid condition was beneficial to the degradation of γ-chlordane and mirex, but the degradation rate of a-chlordane was higher at pH 6.89 than at pH 5.29 or pH 9.18. For soil No. 2 washing effluent, the optimal Cu loading amount was 1.0% , while for soil No. 1 washing effluent, the optimal Cu loading amount was 2.0%.