For further understanding leaching characteristics of heavy metals in tailings and better immobilization on heavy metals against acid rain, batch experiments were conducted. The leaching results of Cu(II), Zn(II), Cd(II) and Mn(II) can be well fit by second-order kinetics equation, and Pb(II) can be well fit by two-constant equation. The leaching intensity of heavy metals in tailings was ranged as: Mn(II)> Cu(II)> Cd(II)> Zn(II)> Pb(II). Triethylenetetramine functioned montmorillonite (TETA-Mt) was successfully synthesized and can obtain simultaneous immobilization effect compared with Mt and TETA, and immobilization rates on Cu(II), Cd(II), Mn(II) and Zn(II) can reach above 90%, the immobilization rate on Pb(II) can reach more than 75%. The mechanisms for efficient immobilization of heavy metals on TETA-Mt included buffering and adsorption abilities. The mechanism for TETA-Mt adsorption of heavy metals included physical absorption, chelation and chemical sedimentation. The results showed that TETA-Mt can be applied to effective immobilization of heavy metals in tailings and efficient remediation of acid mine drainage (AMD) in acid rain area.

为了进一步了解尾矿中重金属的浸出特性，并针对酸雨更好地固定在重金属上，进行了分批实验。Cu（II），Zn（II），Cd（II）和Mn（II）的浸出结果可以通过二阶动力学方程很好地拟合，而Pb（II）可以通过二常数方程很好地拟合。重金属在尾矿中的浸出强度范围为：Mn（II）> Cu（II）> Cd（II）> Zn（II）> Pb（II）。成功合成了三亚乙基四胺功能蒙脱土（TETA-Mt），与Mt和TETA相比可同时获得固定作用，对Cu（II），Cd（II），Mn（II）和Zn（II）的固定率可达到90以上％，Pb（II）的固定率可以达到75％以上。将重金属有效固定在TETA-Mt上的机制包括缓冲和吸附能力。TETA-Mt重金属吸附的机理包括物理吸收，螯合和化学沉降。结果表明，TETA-Mt可用于尾矿中重金属的有效固定和酸雨地区酸性矿山排水（AMD）的有效修复。