复合淋洗剂对熔炼厂遗留场地土壤Pb、Cd的浸提效果

Extraction of Pb and Cd from soil left by a smelter using composite washing agent

以某熔炼厂遗留场地重金属污染土壤作为研究对象,选取柠檬酸(CA)、复合聚天冬氨酸(PASP)、十二烷基苯磺酸钠(SDBS)作为淋洗剂,采用振荡淋洗法研究了不同浓度和配比的单一淋洗剂和复合淋洗剂对污染土壤Pb和Cd的去除效果。实验结果表明:CA、PASP、SDBS单独使用时对Pb和Cd的浸提率均随淋洗剂浓度提高而增大,CA对Pb、PASP对Pb、SDBS对Cd的最高浸提率分别为45.71%、63.69%和39.04%;CA-PASP复合淋洗剂淋洗Pb时有拮抗作用,单独使用PASP淋洗Pb效果更好,CA-PASP复合淋洗剂对Cd的浸提率较低;CASDBS复合淋洗剂效果最佳,对Pb和Cd的最高浸提率分别为55.22%和73.90%。

Citric acid（CA）combined with polyaspartic acid（PASP）or sodium dodecyl benzene sulfonate（SDBS）were evaluated using batch experiments and at different concentration ratios to determine their ability to reduce Pb and Cd in a heavy metal contaminated soil left by a smelter in Shandong province. The results showed：When used alone,CA,PASP and SDBS showed increasing extraction efficiency towards Pb and Cd with the rising of washing agent concentrations. Maximum extraction rates of Pb with CA,Pb with PASP and Cd with SDBS were 45.71%,63.69% and 39.04%,respectively;Composite system of CA-PASP had antagonistic effect for the extraction of Pb,while PASP alone had better extraction efficiency,CA-PASP was also less effective in the extraction of Cd;CA-SDBS exhibited the most effective removal of Pb and Cd,with respective extraction efficiencies of 55.22% and 73.90%.