Synthesis Of Asymmetric Amide-type Functionalized Ionic Liquids And Their Extraction Of Ln And An

In recent years,functional ionic liquids have become the new darling of the spent fuel reprocessing field,favored by researchers as a green and environmental friendly diluent.However,there is little report about the use of ionic liquids as extractants for solvent extraction of spent fuel reprocessing.Therefore,this work is intended to fill this gap and study the extraction behavior of lanthanides and actinides ions when the ionic liquid is used both as a diluent and extractant to provide some theoretical basis for the subsequent spent fuel reprocessing.In this paper,the imidazole-type ionic liquid is functionalized,and it is connected with the succinamide group which has the extraction capacity,which gives the ionic liquid the characteristics of both the diluent and the extractant.The target product was synthesized by two step synthesis,and the lanthanides and actinides ions in aqueous phase were extracted by solvent extraction.By changing the length of the alkyl group on the nitrogen atom of succinamide and the alkyl chain on the nitrogen atom on the imidazole ring,we have synthesized nine functional ionic liquid compounds and purified each step of the product.The structure was characterized by C-NMR spectra and H-NMR spectra.The extraction efficiency of UO₂²⁺,Th⁴⁺,La³⁺,Eu³⁺and Lu³⁺in nitric acid medium by functional ionic liquids was studied systematically.Various factors that affect extraction efficiency,such as extraction equilibrium time,nitric acid concentration,salting-out effect were studied.The influence of the length of the alkyl substituent on the extractant's extraction capacity was studied;a stripping experiment was also conducted to study the possibility of repeated use of the extractant.The possibility of applying it to the separation of uranium and thorium and separation of lanthanides and actinides was examined.The experimental results show that C4 series and C8 series functional ionic liquids have better extraction performance,among which 3-bis?N-methyl-N-butylcarbamoyl?-1-butylimidazolium bis?trifluoromethylsulfonyl?imide functional ionic liquid has the best extraction efficiency of UO₂²⁺,and its SF _U?VI?/Th?IV?is up to45,and it did't extract La³⁺,Eu³⁺,and Lu³⁺,so it was selected as the best extractant in this paper.