生物质三维碳凝胶/钛酸盐纳米复合材料对铷、铯的高选择性吸附及作用机理研究

青海盐湖含有丰富的铷、铯资源，对铷、铯的提取和分离已成为盐湖化工科学的研究热点。作为对铷、铯离子具有很好选择吸附性的纳米钛酸盐(NTs)材料，其纳米结构及大比表面积是获得高吸附容量的主要因素，但纳米粉体不适于装柱。生物质三维碳凝胶(CGs)具有复杂的网络结构与良好的化学兼容性，能提高NTs的比表面积与抗团聚性能，且易于分离。本项目拟以CGs为骨架，通过水热法将NTs包覆在碳凝胶表面，合成具有特殊孔径结构的三维碳凝胶/纳米钛酸盐(CGs/NT)复合材料。通过研究CGs/NT复合材料制备工艺参数及其与结构和性能之间的关系，探索其吸附性能与作用机理。采用静态与动态吸附法考察CGs/NT复合材料的对Rb+、Cs+的吸附性能，研究竞争离子、溶液酸碱性、温度等对Rb+、Cs+的选择性影响；研究CGs/NT复合材料的脱附和循环利用性能。开发适于盐湖铷、铯资源分离提取的新型纳米材料和新技术。

There are many kinds of rare metal ions such as Rb+, Cs+ in salt lakes, which widely distribute in Qinghai salt lakes. The comprehensive utilization of saline resources, special reclaimed utilization of rare element such as rubidium and cesium resources, have aroused much attention with the development of Qinghai saline exploitable resources. Inorganic exchanger based on nano titanates (NTs) show specific selectivity for rubidium and cesium ions in salt loaded solutions. The nano structure and specific surface area are the main factors to influence the high adsorption capacity of NTs, and NTs are not suitable for loading the column. The three-dimensional (3D) biomass carbonaceous gels (CGs) as CG monoliths not only assure a large specific surface areas, good chemical compatibility and high thermal stabilities for promising supports of NTs but also guarantee trouble-free separation of the adsorbents from solutions. In this proposal, the 3D CGs–based composite adsorbent will be synthesized using NTs as the adsorption-active component and CGs as the matrix material. We're ready to synthesize the 3D biomass carbonaceous gels/nano titanates (CGs/NT) composite materials by incorporating NTs into the networks of CGs by hydrothermal method. To study the relationship between process parameters and the properties of CGs/NT composite, and to explore CGs/NT's adsorption capacity and the mechanism, dynamic and static methods are used to investigate the adsorption of Rb+, Cs+ by the CGs/NT compounds in salt loaded solutions. The influence of competitive ions, pH and temperature etc. on the adsorption of Rb+, Cs+ ions onto CGs/NT will be studied through kinetic curves, adsorption isotherms and column techniques. Also, the eluting property, regeneration and reusability of CGs/NT will be examined to evaluate its potential application. The results show the driection for the development of new nano materials and new technologies for the separation and extraction of rubidium and cesium resources in Saline Lake.