重金属与富里酸的竞争络合作用对其在多孔介质中运移的影响

为了研究在土壤地下水环境中运移时,多种重金属在可溶性有机质上的竞争络合作用,于阜新彰武采集草炭土并提取富里酸(FA),通过柱实验,分析了重金属与FA在多孔介质(石英砂柱)中共同运移时,FA对重金属Zn~(2+)、Cd~(2+)和Pb~(2+)运移的促进或抑制作用,以及这些重金属在FA上的竞争作用。结果表明,FA与单一组分重金属(Zn~(2+)、Pb~(2+)、Cd~(2+))在多孔介质中共同运移时,运移能力大小排序为Zn~(2+)Cd~(2+)Pb~(2+);与两组分重金属(Zn~(2+)+Pb~(2+)、Zn~(2+)+Cd~(2+)、Pb~(2+)+Cd~(2+))共同运移时,Zn~(2+)会抑制Pb~(2+)和Cd~(2+)的运移,Cd~(2+)会抑制Zn~(2+)和Pb~(2+)的运移,Pb~(2+)会促进Zn~(2+)和Cd~(2+)的运移;与三组分重金属(Zn~(2+)+Pb~(2+)+Cd~(2+))共同运移时,竞争运移的能力大小为Zn~(2+)Cd~(2+)Pb~(2+)。

Competitive Complexation Effect of Heavy Metals and Fulvic Acid on Heavy Metal Migration in Porous Media

In order to study the competitive complexation of heavy metals on the soluble organic matter when they migrate into soil or groundwater, peat soil was collected from Zhangwu of Fuxin City and fulvic acid (FA) was extracted from it. Column experiment of Zn²⁺, Cd²⁺ and Pb²⁺ with FA in porous media (quartz sand column) was carried out. Results show that the transportation capacity is in the order of Zn²⁺ > Cd²⁺ > Pb²⁺ when a single component heavy metals (Zn²⁺,Pb²⁺ and Cd²⁺) migrated together with FA into porous media; when two heavy metals (Zn²⁺+Pb²⁺, Zn²⁺+Cd²⁺ and Pb²⁺+Cd²⁺) migrated together with FA into porous media, the migration of Pb²⁺ and Cd²⁺ is inhibited with the existence of Zn²⁺ in the solution; the migration of Zn²⁺ and Pb²⁺ is inhibited with the existence of Cd²⁺ in the solution; and the migration of Zn²⁺ and Cd²⁺ is facilitated with the existence of Pb²⁺ in the solution. When three heavy metals (Zn²⁺+Pb²⁺+Cd²⁺) migrate together with FA into porous media, the migration ability of them is in the order of Zn²⁺ > Cd²⁺ > Pb²⁺.