蛭石对水中重金属离子的吸附性能

Adsorption Properties of Heavy Metal Ions in Water by Vermiculite

多金属矿山尾矿库渗滤液造成的地下水重金属污染严重,为有效利用矿物材料对地下水中重金属吸附,在对新疆尉犁蛭石进行定性、定量分析的基础上,通过静、动态吸附实验,研究了其对多金属硫化物尾矿渗滤液中常见的Cu^(2+)、Pb^(2+)、Zn^(2+)、Mn^(2+)的单独或共存状态下的吸附行为及吸附机理。研究表明:蛭石对Cu^(2+)、Pb^(2+)、Zn^(2+)、Mn^(2+)的吸附量分别为49.53、108.00、44.11 mg/g和32.47 mg/g,并且吸附符合Langmuir等温吸附模型,为单分子层吸附,吸附机理为层间离子交换、表面静电和表面络合共同作用。在动态吸附实验的条件下,蛭石填料在528 h达到平衡浓度,作用时间较长。完善了蛭石对多种重金属作用的基础性工作,并且蛭石在PRB技术中的长期运行,可为PRB矿物介质材料设计和优化提供重要指导。

In this paper,the adsorption behavior and mechanism of Cu^(2+)、Pb^(2+)、Zn^(2+)and Mn^(2+)ions in the leachate of polymetallic sulfide tailings with vermiculite from Yuli Xinjiang,China were investigated.The results indicate that the adsorption capacities of vermiculite for Cu^(2+),Pb^(2+),Zn^(2+),Mn^(2+)ions are 49.53 mg/g,108.00 mg/g,44.11 mg/g,32.47 mg/g,respectively,and the monolayer adsorption process follows the Langmuir isothermal adsorption model.The adsorption mechanism is due to a combined effect of interlayer ion exchange,surface static electricity and surface complexation.Vermiculite as a filler reaches the equilibrium concentration for 528 h,and the running time is longer under the dynamic adsorption condition.This work can provide a guidance for the design and optimization of vermiculite as an adsorbent for removal of heavy metal ions in groundwater.