Effectiveness and Mechanisms of Chemical Leaching Combined with Electrokinetic Technology on the Remediation of Heavy Metal Contaminated Soil

被引：2
|
作者：
Ma Q. [1 ,2 ]
Wei Z.-B. [1 ]
Wu Q.-T. [1 ]
机构：
[1] College of Natural Resources and Environment, South China Agricultural University, Guangzhou
[2] School of Resource Environment and Safety Engineering, University of South China, Hengyang
来源：
Huanjing Kexue/Environmental Science | 2023年 / 44卷 / 03期
关键词：
chemical leaching; contaminated soil; electrokinetic remediation; heavy metal; mechanism;
D O I：
10.13227/j.hjkx.202204269
中图分类号：
学科分类号：
摘要：
In this study, chemical leaching and electrokinetic technology were used to remediate heavy metal contaminated soil to elucidate its effectiveness and mechanisms. Chemical leaching agents of FeCl3 , Fe(NO3 )3 , KCl, KNO3 , and HCl solutions were selected, and the effects of Fe3 + , K + , H + , and Cl - on four heavy metal (Cd, Pb, Cu, and Zn) removals were compared and analyzed. Then, the influence of the speciation of heavy metals in soil after chemical leaching on the electrokinetic remediation efficiency was studied. The results showed that Fe3 + , K + , H + , and Cl - had different effects on the four heavy metal removals; for Cd and Zn, the removal effect of H + was the most effective, but for Pb and Cu, the effect of Fe3 + was the most obvious. On the whole, FeCl3 and Fe(NO3 )3 showed the best removal effect for Cd, Pb, and Cu. For the removal of Zn from the soil, the difference in the removal effect of the five leaching agents was not obvious. In comparison with that of FeCl3 and Fe(NO3 )3 , the HCl solution had a moderate removal effect on the four heavy metals in the soil, and the neutral salts KCl and KNO3 had little removal effect on the four heavy metals. Especially for Cd and Cu, KCl and KNO3 addition significantly increased the removal of heavy metals through the subsequent electrokinetic remediation. After the chemical leaching, electrokinetic remediation could make heavy metals in the topsoil (0-10 cm) migrate downward and enrich the 10-20 cm and 20-30 cm soil layers, which requires further studies to resolve. © 2023 Science Press. All rights reserved.
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页码：1668 / 1677
页数：9
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