School of Environmental Science and Engineering, Sun Yat-sen University, 135 Xin Gang Road West, Guangzhou 510275, China.
J Hazard Mater. 2010 Jun 15;178(1-3):578-87. doi: 10.1016/j.jhazmat.2010.01.124. Epub 2010 Feb 1.
To assess the influence of soil washing with a chelator on the chemical immobilization of heavy metals, batch experiments were performed on the fine fraction of a contaminated soil under various operating conditions. Results show that pre-washing with EDTA facilitated the chemical immobilization of Cu and Cr, while an opposite effect for Pb and Zn was observed, in particular when Ca(OH)(2) was added as the immobilizing agent. Metal fraction analyses of the soils indicate that soil washing can reduce the metal mobility by removing the labile fractions, while it may also destabilize some strongly bound fractions, reversely increasing the mobility and thus compromising the subsequent immobilization performance to some extents. To secure an effective combination of soil washing and chemical immobilization for the remediation of heavy metal-contaminated sites, a comprehensive study on metal fraction distribution in the soil is needed.
为了评估螯合剂土壤淋洗对重金属化学固定化的影响，在各种操作条件下，对受污染土壤的细颗粒部分进行了批量实验。结果表明，EDTA 预洗有利于 Cu 和 Cr 的化学固定化，而 Pb 和 Zn 则观察到相反的效果，特别是当添加 Ca(OH)(2)作为固定剂时。土壤金属形态分析表明，土壤淋洗可以通过去除不稳定部分来降低金属的迁移性，但它也可能使一些强结合部分不稳定，反而增加其迁移性，从而在一定程度上影响后续的固定化性能。为了确保土壤淋洗和化学固定化的有效结合，用于修复重金属污染场地，需要对土壤中金属形态分布进行综合研究。
