Investigation of Enhanced Am Selectivity for Eu in Solvent Extraction Using a BTPhen Ligand Substituted with Halogen

Overview

Journal RSC Adv

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2023 Feb 6

PMID 36741186

Authors

Yuto Fukasawa

Satoru Nakashima

Affiliations

Soon will be listed here.

Abstract

The effect of bromine (Br) on the separation of Am/Eu using BTPhen was investigated using DFT calculations. The simulated results agreed well with the reported experimental result of Br substitution. It is concluded that the contribution of the d orbital becomes less important by increasing the number of Br atoms, that is, the relative contribution of the f orbital becomes important. The Am f orbital contributed to both bonding and antibonding interactions with the ligand, whereas the Eu f orbital contributed to the antibonding interaction with the ligand. To study the halogen effect systematically, we introduced a series of new halogen atoms (chlorine, fluorine, iodine) into BTPhen. When the electronegativity of the halogen atom increases, the Δ for complex formation shifts to the positive direction, and the ΔΔ which shows the difference in Δ between Am and Eu becomes a large negative value, suggesting that the Am selectivity is larger. This is due to the increased Δ (= (Am) - (Eu)) between the metal and the ligating nitrogen atom with an increase of electronegativity of the halogen atom.

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