THE THEORETICAL STUDY OF ADSORPTION OF METAL IONS ON CHITOSAN

• 作者: LIU Chenguang LU Renqing QIU Guangmin ZHANG Hongyu
• 来源期刊: 中国反应性高分子：英文版
• 学科: 工学
• 关键词: 壳聚糖 金属离子 吸附 密度函数理论 基组
• 年，卷（期）: 2005,（1）
• 页码范围: 76-81
• 页数: 6页
• 分类号: TQ028.3

摘要

The interactions between metal ions such as Zn2+, Pb2+, Mn2+, Hg2+, Cd2+, Ni2+ and chitosan have been investigated using the model cluster model method and density functional method. Full optimization and frequency analysis of all cluster models have been performed employing B3LYP hybrid method at 3-21G basis set level except metal ions which were invoked to use effective core potential (ECP) method. The energy changes, and the main structural parameters have been obtained during the theoretical study of the adsorption of metal ions on the chitosan. The calculations showed that the coordination modes of metal ions with chitosan models were different, the geometries of Mn2+, Zn2+, Cd2+, Hg2+, Pb2+ ions coordinated with two nitrogen atoms and two oxygen atoms were distorted tetrahedral, while the square planar structure of Ni2+ coordinated two nitrogen atoms and two oxygen atoms was observed. The heat of reaction between six metal ions and chitosan models showed the order: Mn2+ ＞Ni2+ ＞Zn2+ ＞Pb2+ ＞Hg2+ ＞Cd2+, this suggested that the coordination strength of Mn2+ ＞Ni2+ ＞Zn2+ ＞Pb2+ ＞Hg2+ ＞Cd2+.