金属有机框架材料用于海水提铀的研究进展

Progress of metal-organic frameworks for uranium extraction from seawater

随着核能需求的增加,从海水中提取铀作为传统铀资源的补充或替代具有重要意义。金属有机框架材料(MOFs)具有高的比表面积和可调控的孔结构,作为一种新兴的除铀吸附剂,在学术界已引起了广泛关注。针对MOFs在海水中吸附铀时存在的水稳定差、选择吸附性差和分离困难等关键问题,研究发现可以通过定向官能化改性和与异相材料复合来提高海水提铀性能。本文简要介绍了MOFs材料在水中提取铀的结构优势,分析了水稳定性的影响因素,列举了具有代表性的三类高水稳定性MOFs材料特性,重点总结了该三类MOFs应用于海水中提取铀的性能以及机制研究,同时比较了原始MOFs、表面官能化MOFs和MOFs复合材料的提铀性能。基于MOFs的结构特征与对铀酰离子的吸附作用机制,得出除铀MOFs吸附剂的未来发展方向是提高水体稳定性、进行MOFs表面功能化以及拓展多种材料复合方式。

With the increasing demand for nuclear energy,it is of great significance to extract uranium from seawater as a supplement or substitute for traditional uranium resources.Owing to the high specific surface area and tunable pore structure,metal-organic frameworks(MOFs)have attracted extensive attention in academia as a novel adsorbent for uranium capture.Regarding the water instability,low selectivity and difficult separation of MOFs from seawater after uranium capture,these issues can be addressed by surface modification and composite with heterogeneous materials.This paper briefly introduced the structural advantages of MOFs materials for uranium extraction in water,analyzed the influence factors of water stability,listed the properties of three representative types of water-stable MOFs materials,summarized the performance of these MOFs applied to extract uranium from seawater and investigated the mechanism.Meanwhile,the uranium extraction performance by pristine MOFs,surfacefunctionalized MOFs and MOFs composites are compared.Based on the structural characteristics of MOFs and the adsorption mechanism of uranyl ions,it is concluded that the future development direction of uranium-removing MOFs adsorbents is to improve water stability,perform surface functionalization of MOFs and expand multiple material composite methods.