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...
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| Main Authors: | , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
June 30, 2010
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| 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 |
| Author Notes: | Denise Girnt, Peter W. Roesky, Andreas Geist, Christian M. Ruff, Petra J. Panak, and Melissa A. Denecke |
| 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. |
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| Item Description: | Gesehen am 28.03.2023 |
| Physical Description: | Online Resource |
| ISSN: | 1520-510X |
| DOI: | 10.1021/ic101309j |