天然有机酸对污染土壤中Cd和Cu萃取效果的对比研究

以沈阳市张士灌区受污染土样为供试样品,采用振荡离心法研究了柠檬酸、酒石酸和草酸这3种天然有机酸对供试土样中Cd和Cu的去除能力。结果表明:随着浓度的提高,3种萃取剂对Cd和Cu的去除作用增强。对Cd和Cu去除率的顺序为Cd>Cu,3种有机酸对Cd的去除能力顺序为柠檬酸>酒石酸>草酸,对Cu的去除能力顺序为酒石酸>柠檬酸>草酸。但柠檬酸处理后土壤中Cu的碳酸盐结合态反而有所增加的现象应值得注意。

A leaching technology was applied to treat the soil contaminated by Cd and Cu in Shenyang Zhangshi irrigation area using three organic acids. Batch experiments were performed to test the extraction capacity of the three organic acids. The results show that, with increasing in citric acid, tartaric acid and oxalic acid concentrations, removals of Cd and Cu significantly increased. The removal percentages of heavy metals were in a sequence of Cd〉Cu, the removal abilities of Cd were citric acid 〉 tartaric acid 〉oxalic acid, the removal abilities of Cu were tartaric acid 〉 citric acid〉 oxalic acid. But the carbonate bound of Cu increased due to the extracting of citric acid, which should be concerned with.