离子筛——一种具有离子记忆效应的材料结构与性能研究

In this project, high pure LiMn2O4 with normal spinel structure was prepared by template synthesis introducing Li+ ion, and it has perfectly grown crystal grain and specific memory for lithium ions. After leached with acid and extraction of Li+ ion introduced in column, the λ-MnO2 was obtained, it remains the same framework to the precursor and has specific adsorption for Li+ ion. The influence of synthesis methods and conditions on the structure and properties of the product obtained was investigated systematically. The optimum process and conditions for synthesis were established, and the reaction mechanism was studied also. The results show that for the lithium ion the adsorption capacity of λ-MnO2, which was made from the precursor prepared through solid reaction is 3.80 m mol/g at pH 12.0. In neutrality condition the distribution coefficient for Li+ ion and Na+ ion is 3.406×104 and 2.3 respectively, and the separation coefficient is 1.481×104 for above two ions(pH=6.5), the period needed for leaching is 168h. The ion-sieve can be used repeatedly. As a result, this ion memory material can be developed as ion-sieve for the separation of some specific ions. The ion-sieve property of λ-MnO2, which was made from the precursor synthesized through Sol-Gel is better than that from the precursor synthesized through solid reaction. In addition, the porous glass was used as ion-sieve matrix, the adsorption and separation properties for some alkali metal ions and alkaline earth metal ions were investigated in this project.

离子筛是一种具有特殊记忆效应的离子交换体，通过在前驱体中导入目的离子，熔合固定处理后，在保持结构架不变情况下，将导入离子抽出，基体中会形成规则的微细孔穴，其对原目的离子具有高的选择吸附效应。通过研究其制造方法及性能，可以制备出用于物质提取、分离、海水脱盐等专用的离子筛分材料，从而开发出有效的“绿色”化学处理方法。