Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study

doi:10.1021/acs.jpca.8b00177

	Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study
	Shi, WQ; Kong XH(孔祥鹤); Wu QY(吴群燕); Wang CZ(王聪芝); Lan JH(蓝建慧); Chai ZF(柴之芳); Shi WQ(石伟群); Kong, XH; Wu, QY; Wang, CZ
刊名	JOURNAL OF PHYSICAL CHEMISTRY A
	2018
卷号	122 期号:18 页码:4499-4507
ISSN号	1089-5639
DOI	10.1021/acs.jpca.8b00177
文献子类	Article; Proceedings Paper
英文摘要	Separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is one of the most important steps in spent nuclear fuel reprocessing. However, it is very difficult and challenging to separate them due to their similar chemical properties. Recently the pyridylpyrazole ligand (PypzH) has been identified to show good separation ability toward Am(III) over Eu(III). In this work, to explore the Am(III)/Eu(III) separation mechanism of PypzH at the molecular level, the geometrical structures, bonding nature, and thermodynamic behaviors of the Am(III) and Eu(III) complexes with PypzH ligands modified by alkyl chains (Cn-PypzH, n = 2, 4, 8) have been systematically investigated using scalar relativistic density functional theory (DFT). According to the NBO (natural bonding orbital) and QTAIM (quantum theory of atoms in molecules) analyses, the M-N bonds exhibit a certain degree of covalent character, and more covalency appears in Am-N bonds compared to Eu-N bonds. Thermodynamic analyses suggest that the 1:1 extraction reaction, [M(NO3)(H2O)(6)](2+) + PypzH + 2NO(3)(-) -> M(PypzH)(NO3)(3)(H2O) + 5H(2)O, is the most suitable for Am(III)/Eu(III) separation. Furthermore, the extraction ability and the Am(III)/Eu(III) selectivity of the ligand PypzH is indeed enhanced by adding alkyl-substituted chains in agreement with experimental observations. Besides this, the nitrogen atom of pyrazole ring plays a more significant role in the extraction reactions related to Am(III)/Eu(III) separation compared to that of pyridine ring. This work could identify the mechanism of the Am(III)/Eu(III) selectivity of the ligand PypzH and provide valuable theoretical information for achieving an efficient Am(III)/Eu(III) separation process for spent nuclear fuel reprocessing.
会议地点	Cambridge, ENGLAND
WOS关键词	DENSITY-FUNCTIONAL THEORY ; SEGMENTED CONTRACTION SCHEME ; PSEUDOPOTENTIAL BASIS-SETS ; ACTINIDE(III)/LANTHANIDE(III) SEPARATION ; SELECTIVE EXTRACTION ; ELECTRONIC-STRUCTURE ; TRIVALENT ACTINIDE ; COMPLEXES ; LANTHANIDE ; LIGANDS
WOS研究方向	Chemistry ; Physics
语种	英语
WOS记录号	WOS:000432204200014
内容类型	期刊论文
源URL	[http://ir.ihep.ac.cn/handle/311005/285914]
专题	高能物理研究所_多学科研究中心
通讯作者	Shi WQ(石伟群)
作者单位	中国科学院高能物理研究所
推荐引用方式 GB/T 7714	Shi, WQ,Kong XH,Wu QY,et al. Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study[J]. JOURNAL OF PHYSICAL CHEMISTRY A,2018,122(18):4499-4507.
APA	Shi, WQ.,孔祥鹤.,吴群燕.,王聪芝.,蓝建慧.,...&Nie, CM.(2018).Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study.JOURNAL OF PHYSICAL CHEMISTRY A,122(18),4499-4507.
MLA	Shi, WQ,et al."Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study".JOURNAL OF PHYSICAL CHEMISTRY A 122.18(2018):4499-4507.