Rational design of novel carboxylic acid functionalized phosphonium based ionic liquids as high-performance extractants for rare earths  

作　　者：Yi Zhang Weidong Guo Donghao Liu Jie Xu 

机构地区：[1]Key Laboratory of Green Chemical Process of Ministry of Education,School of Chemical Engineering and Pharmacy,Wuhan Institute of Technology,Wuhan 430073,China

出　　处：《Journal of Rare Earths》2021年第11期1435-1441,I0005,共8页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(51804223)。

摘　　要：Developing the novel ionic liquids as the potential substitutes for conventional organic solvents in extraction of the rare-earth metals is highly desirable but challenges still remain.In this study,the welldesigned carboxylic acid functionalized phosphonium based ionic liquids,(4-carboxyl)butyl-trioctylphosphonium chloride/nitrate,were synthesized and characterized.The as-prepared samples were tested as the undiluted hydrophobic acidic extractant for rare-earth metal ions,affording the maximal loading of 3 mol/mol towards Nd(Ⅲ)in aqueous solution and the remarkable stripping performance.The results also reveal their excellent extractability and selectivity for Sc(Ⅲ)in the mixtures of six rare-earth ions,as well as the outstanding separation properties between rare-earth and first row transition-metal ions(i.e.,La/Ni,Sm/Co).Moreover,the extraction mechanism indicates that the extracted rare-earth complex via a proton exchange in the ionic liquid phase is structurally similar to the complexes obtained with neutral extractants.This work presents a prototype for the fabrication of the hydrophobic cation-functionalized ionic liquids for highly efficient rare-earth extraction and provides the future application in recycling of rare-earth metals from the spent magnets.

关 键 词：Ionic liquids Rare earths Solvent extraction Ion exchange 

分 类 号：TF845[冶金工程—有色金属冶金]