含N固相吸附材料分离高放废液中镧系和锕系元素的研究进展

Advances on separation of lanthanides and actinides from high-level waste liquids using N-containing solid phase adsorption material

乏燃料中镧锕分离的主要方法是溶剂萃取法和固相萃取法,与溶剂萃取技术相比,固相萃取法具有相分离容易且不产生第三相,操作设备小型且简单,有机溶剂用量少和二次废物产生量少的优点。在分离乏燃料镧系元素和锕系元素的固相材料中,选取了以SiO2和树脂为基体合成的含N固相吸附材料作为研究对象,其合成方法主要包括物理灌装和化学改性,物理灌装法即将含N萃取剂负载到SiO2/树脂的微孔中获得的固相吸附材料,灌装后萃取剂含量高达30%~40%,而化学改性法是将配体官能团通过化学反应接枝到基体上得到固相吸附材料。本文综述了这两类吸附材料的制备方法、分离镧系和锕系元素的吸附条件,以及相应的分离效果和吸附机理。与液液萃取法分离镧系和锕系元素相比,采用树脂和SiO2为载体的含N固相吸附材料具有成本低、几乎不产生有机废液、适用于稀溶液等优点。

This paper aims to review on the synthesis and Lanthanides/Actinides separation performance of Ncontaining solid-phase adsorption materials in treatment of high-level waste liquids.The main technology of separating lanthanides and actinides in the spent fuel processing are solvent extraction and solid phase extraction.Compared with solvent extraction,solid phase extraction has some unique advantages such as no possibility of third phase formation,more compact equipment,less organic solvent utilization and less secondary waste generation.Ncontaining solid phase adsorption materials,synthesized by physical impregnation or chemical modification with SiO2 and resin as solid carriers,respectively,were taken as research object.In physical impregnation method,Ncontaining extractant was loaded into the micropores of SiO2 or resin,and the content of extractant was as high as 30%~40%after filling whilst the chemical modification method was to graft the ligand functional groups onto the matrix through chemical reaction to obtain solid-phase adsorption materials.The preparation methods and the adsorption conditions of these N-containing solid phase adsorption materials are reviewed in this paper,as well as the adsorption mechanisms and the separation efficiency of lanthanides and actinides.Compared with the separation of lanthanide and actinide by liquid-liquid extraction,N-containing solid-phase adsorption material with resin and SiO2 as carrier has the advantages of low cost,almost no organic waste liquid and suitable for dilute solution.