巯基树脂吸附重金属离子机理的研究

The Study on Adsorption Mechanism for Heavy Metal Ions of Sulfhydryl-Resib

研究了自合成的巯基树脂对重金属离子Pb2+,Cu2+,Co2+,Ni2+,Cd2+的吸附容量、吸附动力学、等温吸附过程等静态吸附性能,影响吸附的因素和吸附机理。结果表明,该树脂对软酸型重金属离子吸附容量高。pH=5.0～5.7,低温有利于吸附,树脂对各重金属离子等温吸附在实验浓度范围内均符合Langmuir和Freundlich方程。吸附机理研究表明,巯基与重金属离子发生了离子交换和螯合反应,化学吸附起支配作用。

The sulfhydryl-resin was prepared and its static adsorption properties for metal ions (Pb^(2+), Cu^(2+), Co^(2+), Ni^(2+),Cd^(2+)) such as capacities, kinetics and isotherm were studied. The influencing factors and mechanism of adsorption were also investigated. The results indicate that this resin has higher adsorption capacities for heavy metal ions with 'soft acid' type. The proper adsorption conditions are pH=5.0～5.7 and lower temperature. The adsorption isotherms conform mainly to Langmuir and Freundlich equation within the range of experimental concentrations. The research on mechanism shows that ion exchange and chelating reaction occured between resin and the metal ions, and chemical adsorption is dominant in this kind of chemical process.