重金属污染土壤萃取方法选择及参数优化

Selection of extraction procedures and optimization of parameters for the determination of forms of heavy metals in soils

土壤重金属污染是国际土壤与环境研究的热点和难点问题之一。重金属在土壤中存在的形态和各种形态的比例是决定其迁移性和生态影响的关键因素。常用的形态分析方法包括Tessier五步萃取法、BCR三步萃取法和水萃取法等。在比较三种萃取方法的基础上,在法国北部冶炼厂周围土壤和焦作矿区土壤污染研究中采用水乙酸两步萃取法,采用蒸馏水和0 11 mol/L的乙酸,液固比20,25 ℃条件下恒温振荡16 h。

The problem of soil contamination with heavy metals is of increasing interest worldwide. The mobility of trace metals and related ecological effects depend on their specific chemical forms or the ratio between different forms. Typical extraction procedures include the Tessier five-step procedure, BCR three-stage procedure and water-acetic procedure. Based on the comparison among these procedures, the water-acetic procedure was adopted to evaluate the mobility of heavy metals in Lille,France and in Jiaozuo, Middle China. Liquid-to-Solid Ratio was 20, and batch extractions were performed in a tube rotator device for 16 hours at 25 ℃.