A Novel Functionalized Ionic Liquid for Highly Selective Extraction of TcO4

Yiwei Huang; Xiaomin Li; Fei Wu; Suliang Yang; Fangfei Dong; Xupeng Zhi; Xinlong Chen; Guoxin Tian; Yinglin Shen

doi:10.1021/acs.inorgchem.2c01775

A Novel Functionalized Ionic Liquid for Highly Selective Extraction of TcO₄

Inorg Chem. 2022 Jul 11;61(27):10609-10617. doi: 10.1021/acs.inorgchem.2c01775. Epub 2022 Jun 27.

Authors

Yiwei Huang¹, Xiaomin Li¹, Fei Wu¹, Suliang Yang², Fangfei Dong¹, Xupeng Zhi¹, Xinlong Chen¹, Guoxin Tian², Yinglin Shen¹

Affiliations

¹ School of Nuclear Science and Technology; Frontier Science Center for Rare Isotopes, Lanzhou university, 730000 Lanzhou, China.
² Radiochemistry Department, China Institute of Atomic Energy, Beijing 102413, China.

PMID: 35758888
DOI: 10.1021/acs.inorgchem.2c01775

Abstract

Due to the highly acidic and high-salinity nature of the high-level radioactive waste liquid (HLLW), selective extraction of TcO₄^- from HLLW remains to be a challenging task. Traditional anion exchangers show low selectivity and unsatisfactory extraction performance due to the lack of functional groups that can interact strongly with TcO₄^-. In this work, a tailor-made binding site was constructed by decorating two acetamide functional groups on imidazolium cation to fabricate a new Tc separation material, which exhibits high selectivity. Unlike most reported Tc separation materials, which can only perform well under low acidic, neutral, or alkaline conditions, this material still has good extraction performance in highly acidic solutions. In the simulated high-level waste liquid of 3 M nitric acid, the extraction efficiency of 0.5 mol/L organic phase for Tc can reach 96.5% through the first-stage extraction. Our theoretical simulations suggest that ReO₄^-/TcO₄^- anions were adsorbed on the top of the imidazolium ring during the extraction process, with p-π and p-p interactions acting as the driving forces.