6-(3,5-Dimethyl-1H-pyrazol-1-yl)-2,2′-bipyridine as ligand for Actinide(III)/Lanthanide(III) separation

With the aim of better understanding the selectivity of the established system 2,6-ditriazinylpyridine (BTP) for actinide(III)/lanthanide(III) separations, a related model system was synthesized and studied. The N donor complexing ligand 6-(3,5-dimethyl-1H-pyrazol-1-yl)-2,2′-bipyridine (dmpbipy) was...

Full description

Saved in:
Bibliographic Details
Main Authors: Girnt, Denise (Author) , Roesky, Peter (Author) , Geist, Andreas (Author) , Ruff, Christian (Author) , Panak, Petra (Author) , Denecke, Melissa Anne (Author)
Format: Article (Journal)
Language:English
Published: June 30, 2010
In: Inorganic chemistry
Year: 2010, Volume: 49, Issue: 20, Pages: 9627-9635
ISSN:1520-510X
DOI:10.1021/ic101309j
Online Access:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1021/ic101309j
Get full text
Author Notes:Denise Girnt, Peter W. Roesky, Andreas Geist, Christian M. Ruff, Petra J. Panak, and Melissa A. Denecke
Description
Summary:With the aim of better understanding the selectivity of the established system 2,6-ditriazinylpyridine (BTP) for actinide(III)/lanthanide(III) separations, a related model system was synthesized and studied. The N donor complexing ligand 6-(3,5-dimethyl-1H-pyrazol-1-yl)-2,2′-bipyridine (dmpbipy) was synthesized having a fused N heterocycle ring structure modified from the BTP partitioning ligand, and its extraction performance and selectivity for trivalent actinide cations over lanthanides was evaluated. X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), and time-resolved laser fluorescence spectroscopy (TRLFS) results show that 1:1 complexes are formed, unlike the 1:3 complex for BTP systems. The equilibrium constant for curium complex formation with dmpbipy was determined to be log K = 2.80, similar to that for nitrate. The Gibbs free energy, ΔG(20 °C), of 1:1 Cm-dmpbipy formation in n-octan-1-ol was measured to be −15.5 kJ/mol. The dmpbipy ligand in 1-octanol does not extract Am(III) Eu(III) from HNO3 but was found to extract Am(III) with limited selectivity over Eu(III) (SFAm(III)/Eu(III) ≈ 8) dissolved in 2-bromohexanoic acid and kerosene at pH > 2.4.
Item Description:Gesehen am 28.03.2023
Physical Description:Online Resource
ISSN:1520-510X
DOI:10.1021/ic101309j