Selective separation of uranium,zirconium and iodine from various fission products by 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide and phosphoramide-functionalized ionic liquid

In this work, a separation and purification process of U(VI), Zr(IV) and I₂ from various fission products in nitric acid solution by 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (C₄mim]NTf₂]) and dibutyl-3-(3-methylimidazolium)propylphosphoramide bis(trifluoromethanesulfonyl)imide-task specific ionic liquid (phosphoramide-TSIL) was investigated. The phosphoramide-TSIL was found to reduce ligand loss compared to dibutyl propylphosphoramidate by total organic carbon testing (TOC). The stripping of U(VI), Zr(IV) and I₂ could be achieved by guanidine carbonate solution, oxalic acid solution and sodium hydroxide solution, respectively. The phosphoramide-TSIL/C₄mim]NTf₂] showed good irradiation stability and recyclability. Phosphoramide-TSIL has the potential to be applied for separation and purification in the actual radioactive environment.

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