选择带结构负电荷的蒙脱土和带微量结构负电荷的高岭土,研究了其对pb2+的吸附性能,并探讨了吸附机理.研究表明,蒙脱土和高岭土吸附pb2的动力学曲线符合准二级动力学方程,吸附等温线符合Langmuir方程.Pb2+同时以内层配合和外层配合形式吸附,其相对量与pH值有关.在pH值小于4和大于8的范围内,以内层配合物为主；而pH值在4～8范围内外层配合物比例增大.pb2+能进入蒙脱土的层间,而不能进入高岭土的层间；部分pb2+可进入黏土颗粒的微孔中被固定.蒙脱土对pb2+的吸附能力和饱和吸附量明显高于高岭土.%Sorption activities of Pb + on montmorillonite and kaolinite were studied and a sorption mechanism was proposed. The sorption kinetics and the sorption isotherms of Pb2 + on montmorillonite and kaolinite can be described by the pseudo-second-order kinetics and Langmuir isotherm respectively. The sorption mechanism of Pb2+ on the montmorillonite and kaolinite is the surface complex mechanism, simultaneously forming inner-sphere surface complexes and outer-sphere surface complexes. The relative content of inner (or outer)-sphere surface complexes is pH dependent and is dominant beyond (or within) the pH range of 4 ~8, respectively. The sorption amount in mg/g of Pb2+ on montmorillonite is obviously higher than that on kaolinite. The affinity of montmorillonite for Pb2 + is higher than that of kaolinite for Pb2 +.
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