应用化学 ›› 2011, Vol. 28 ›› Issue (12): 1441-1447.DOI: 10.3724/SP.J.1095.2011.00722

• 研究论文 • 上一篇    下一篇

蒙脱土和高岭土对Pb2+的吸附

张树芹*,路福绥,李丽芳,张树芹   

  1. (山东农业大学化学与材料科学学院 泰安 271018)
  • 收稿日期:2010-12-06 修回日期:2011-04-11 出版日期:2011-12-10 发布日期:2011-12-10
  • 通讯作者: 张树芹,副教授; Tel:0538-8246133; Fax:0538-8242251; E-mail:zsqtaian@sdau.edu.cn; 研究方向:污染生态修复及农药稳定性
  • 基金资助:
    国家重大基础研究(“九七三”)计划(2004CB418504)2008年省博士基金(2008BS07016)以及山东农业大学青年创新基金(23621)资助项目

Sorption of Pb2+ on Montmorillonite and Kaolinite

ZHANG Shuqin*, LU Fusui, LI Lifang, SUN Tingting   

  1. (College of Chemistry and Material Science,Shandong Agriculture University,Taian 271018)
  • Received:2010-12-06 Revised:2011-04-11 Published:2011-12-10 Online:2011-12-10

摘要:

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+同时以内层络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。

关键词: 蒙脱土, 高岭土, Pb2 +, 吸附机理

Abstract:

Sorption activities of Pb2+ 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+.

Key words: Montmorillonite, Kaolinite, Pb2 +, Sorption mechanism

中图分类号: