模板辅助高选择性三维网络吸附剂的制备及其对铷、铯、锶吸/脱附性能研究

In recent years, the three-dimensional structured hydrogels, with the characteristics of fast adsorption rate, high adsorption capacity, easy separation and regeneration, are receiving increasing interests for the removal of heavy metals and organic dyes from aqueous solution, but they are not yet available in the comprehensive utilization of salt lake resources, which are recognized as one important part of mineral resources. Up to now, the comprehensive utilization of salt lake resources is mainly aimed at potassium, magnesium, boron and lithium, while the associated scattered elements including but not limited to rubidium, cesium and strontium have not been given sufficient attention. Using various template-assisted foaming agents, this project is proposed to design and develop a series of granular three-dimensional structured adsorbents with different pore size distribution and functional groups. Subsequently, these adsorbents are applied to separate and enrich rubidium, cesium, and strontium in simulated and actual brine solutions. On the basis of in-depth study for the formation of pores within the polymeric networks, the relationship between the distribution of pores as well as the functional groups and selective adsorption properties can be clarified. The adsorption/desorption performance of these scattered elements onto or from the hydrogel materials will be explored in detail. All the obtained results from this project will provide technical support for recovery and recycle of scattered elements in salt lakes.

近年来，三维网络吸附剂因具有吸附速率快、吸附容量高、易分离、易再生等明显优势，在重金属、有机染料等治理方面引起研究者的广泛关注，但尚未在盐湖资源的开发利用方面得以应用。作为矿产资源的重要组成部分，盐湖资源的开发利用目前主要针对钾、镁、硼、锂，而伴生的铷、铯、锶等稀散元素一直未给予足够的重视。本项目拟利用发泡剂的模板辅助作用，通过分子设计构筑一系列含有不同孔隙分布和功能基团的颗粒状三维网络吸附材料，以盐湖资源中铷、铯、锶为研究对象，在深入研究网络内部孔隙形成的基础上，明晰水凝胶中孔隙的分布以及功能基团与盐湖稀散元素的选择性吸附之间的关系；探讨这些稀散离子在水凝胶吸附材料上的脱附行为；最终为实现盐湖中稀散元素的回收利用提供技术支撑。

铷（Rb）、铯（Cs）和锶（Sr）是极为重要的高度分散战略资源，在众多领域发挥着重要作用，而在我国西部盐湖资源中储量巨大。本项目以盐湖资源中铷、铯和锶的分离为研究对象，针对盐湖中稀散元素本身的赋存形态，通过乳液模板方法，结合分子设计制备了一系列含有不同功能基团和孔隙结构的三维网络吸附剂，通过静态吸附和动态吸附评价实验，系统评价了其对碱金属铷、铯和碱土金属锶的吸附性能。同时结合沉淀聚合方法，实现了吸附剂从块状向球形转变，方便了吸附后分离；通过双乳液模板法构筑了多孔吸附微球；拓展研究了纳米凹凸棒石和磁性Fe3O4稳定的三维网络吸附剂对铷、铯和锶的吸附效果。在深入研究网络内部孔隙形成的基础上，明晰了吸附剂中孔隙的分布以功能基与稀散离子吸附性能之间的关系，探讨了这些稀散离子在吸附材料上的脱附行为。该研究结果为实现盐湖中稀散元素的回收利用提供了很好的技术支撑。