Abstract In order to improve the heavy metal removal ability of traditional single washing agents and explore the removal mechanism of heavy metals. Then, the washing reagents that mixed by low-molecular weight organic acids (citric acid, oxalic acid, and tartaric acid) and artificial chelating compound ethylenediaminetetraacetic acid disodium (EDTA) were selected. Furthermore, the effect of soil washing parameters, the variation of leaching toxicity, mobility, stability and speciation of heavy metals were also considered. The results of soil washing experiments showed that mixing an equal volume of 0.05 M EDTA and 0.2 M organic acids (citric acid, oxalic acid, and tartaric acid) could remove more than about 80% heavy metals from soil under the optimal conditions. In addition, the soil leaching toxicity was decreased and the stability of remaining heavy metals was increased, indicating that EDTA-organic acid washing reagents could effectively reduce the ecological risk of contaminated soil. EDTA had a stronger chelating ability with heavy metals than the organic acids, and the organic acids could not only chelate heavy metals but also decrease the pH of the mixture for promoting the desorption of heavy metals. Thus, mixing EDTA and organic acids was advisable method to improve soil washing technology.

中文翻译：

---

EDTA-有机酸洗涤去除工业土壤中的Cu、Ni、Zn

摘要 为提高传统单一洗涤剂的重金属去除能力，探索重金属去除机理。然后选择低分子量有机酸（柠檬酸、草酸、酒石酸）和人工螯合剂乙二胺四乙酸二钠（EDTA）混合的洗涤试剂。此外，还考虑了土壤洗涤参数的影响、浸出毒性、迁移性、稳定性和重金属形态的变化。土壤洗涤实验结果表明，在最佳条件下，将等体积的0.05 M EDTA和0.2 M有机酸（柠檬酸、草酸和酒石酸）混合可去除土壤中约80%以上的重金属。此外，土壤淋溶毒性降低，残留重金属稳定性增加，表明EDTA-有机酸洗涤试剂可有效降低污染土壤的生态风险。EDTA对重金属的螯合能力比有机酸强，有机酸不仅能螯合重金属，还能降低混合物的pH值，促进重金属的解吸。因此，将EDTA和有机酸混合是改进土壤洗涤技术的可取方法。有机酸不仅能螯合重金属，还能降低混合物的pH值，促进重金属的解吸。因此，将EDTA和有机酸混合是改进土壤洗涤技术的可取方法。有机酸不仅能螯合重金属，还能降低混合物的pH值，促进重金属的解吸。因此，将EDTA和有机酸混合是改进土壤洗涤技术的可取方法。