为预测酸雨沉降对重金属含量较大的再生铅厂区土壤重金属浸出规律的影响，以湖北省某大型再生铅企业厂区的土壤样品为研究对象，考察了土壤中Pb、Zn浸出和Al、Fe活化规律。试验结果表明，Pb、Zn的浸出率随乙酸浓度、液固比以及浸出时间的增加而上升。随着浸出pH的增大，浸出率呈先增加后减小的趋势；在乙酸浓度为2.4 mol/L、液固比为10、pH为3.5、浸出时间为12 h时，Pb的最高浸出率达76.4%，Zn仅为23%，表明用乙酸作浸出剂时，Pb比Zn更易从土壤中释放，乙酸对Al和Fe的最高浸出率分别为1.41%和0.61%，所占土壤矿物组分比重极小，基本不影响土壤的正常生态功能。基于Medusa热力学软件研究乙酸浸出土壤过程中重金属的迁移规律，为揭示铅锌浸出和铝铁活化规律提供理论支撑。

To forecast impact of acid precipitation on leaching of heavy metals from the soil nearby secondary lead plant,the leaching efficiency of Pb and Zn,and the activation degree of Al and Fe from soil are studied,while the soil samples are collected from a large-scale secondary lead plant in Hubei province.The results are indicating that the leaching ratios of Pb and Zn increase with the increases of acetic acid concentration,liquid-solid ratio and leaching time.With the increase of pH of leaching solution,the leaching ratios increase firstly and decrease then.The highest leaching ratios of Pb and Zn can reach 76.4% and 23%,respectively when the concentration of acetic acid is 2.4 mol·L^-1,the ratio of liquid to solid is 10,pH 3.5 and leaching time 12 h.It is indicated that Pb is easier to be leached from soil compared with Zn when using acetic acid as leaching agent.The highest leaching ratios of Al and Fe by acetic acid reach 1.41% and 0.61%,respectively.Al and Fe account for smaller part of the total mineral composition,which will not affect the normal ecological function of the soil.Medusa thermodynamic analysis software can be applied to investigate the migration law of main heavy metals from soil during acetic acid precipitation procedure,supplying a theorical support for disclosing the rules in leaching of Pb and Zn,and activation of Al and Fe.

张伟(1988-),男,博士,副教授,主要从事固体资源化回收、纳米材料修复土壤和水体方向研究,zhangwei88@zzu.edu.cn