Display options
Cite
Kratsch J, Beele BB, Koke C, et al. 6-(Tetrazol-5-yl)-2,2'-bipyridine: a highly selective ligand for the separation of lanthanides(III) and actinides(III). Inorg Chem. 2014;53(17):8949-58doi: 10.1021/ic5007549.
Kratsch, J., Beele, B. B., Koke, C., Denecke, M. A., Geist, A., Panak, P. J., & Roesky, P. W. (2014). 6-(Tetrazol-5-yl)-2,2'-bipyridine: a highly selective ligand for the separation of lanthanides(III) and actinides(III). Inorganic chemistry, 53(17), 8949-58. https://doi.org/10.1021/ic5007549
Kratsch, Jochen, et al. "6-(Tetrazol-5-yl)-2,2'-bipyridine: a highly selective ligand for the separation of lanthanides(III) and actinides(III)." Inorganic chemistry vol. 53,17 (2014): 8949-58. doi: https://doi.org/10.1021/ic5007549
Kratsch J, Beele BB, Koke C, Denecke MA, Geist A, Panak PJ, Roesky PW. 6-(Tetrazol-5-yl)-2,2'-bipyridine: a highly selective ligand for the separation of lanthanides(III) and actinides(III). Inorg Chem. 2014 Sep 02;53(17):8949-58. doi: 10.1021/ic5007549. Epub 2014 Jun 26. PMID: 24967733.
Copy Download .nbib Format: NLM
Share it on

Inorg Chem. 2014 Sep 02;53(17):8949-58. doi: 10.1021/ic5007549. Epub 2014 Jun 26.

6-(Tetrazol-5-yl)-2,2'-bipyridine: a highly selective ligand for the separation of lanthanides(III) and actinides(III).

Inorganic chemistry

Jochen Kratsch, Björn B Beele, Carsten Koke, Melissa A Denecke, Andreas Geist, Petra J Panak, Peter W Roesky

Affiliations

  1. Institut für Anorganische Chemie, Karlsruher Institut für Technologie , Engesserstrasse 15, 76131 Karlsruhe, Germany.

PMID: 24967733 DOI: 10.1021/ic5007549

Abstract

The coordination structure in the solid state and solution complexation behavior of 6-(tetrazol-5-yl)-2,2'-bipyridine (HN4bipy) with samarium(III) was investigated as a model system for actinide(III)/lanthanide(III) separations. Two different solid 1:2 complexes, [Sm(N4bipy)2(OH)(H2O)2] (1) and [Sm(N4bipy)2(HCOO)(H2O)2] (2), were obtained from the reaction of samarium(III) nitrate with HN4bipy in isopropyl alcohol, resuspension in N,N-dimethylformamide (DMF), and slow crystallization. The formate anion coordinated to samarium in 2 is formed by decomposition of DMF to formic acid and dimethylamine. Time-resolved laser fluorescence spectroscopy (TRLFS) studies were performed with curium(III) and europium(III) by using HN4bipy as the ligand. Curium(III) is observed to form 1:2 and 1:3 complexes with increasing HN4bipy concentration; for europium(III), formation of 1:1 and 1:3 complexes is observed. Although the solid-state samarium complexes were confirmed as 1:2 species the 1:2 europium(III) solution complex in ethanol was not identified with TRLFS. The determined conditional stability constant for the 1:3 fully coordinated curium(III) complex species is more than 2 orders of magnitude higher than that for europium(III) (log β3[Cm(N4bipy)3] = 13.8 and log β3[Eu(N4bipy)3] = 11.1). The presence of added 2-bromodecanoic acid as a lipophilic anion source reduces the stability constant for formation of the 1:2 and 1:3 curium(III) complexes, but no ternary complexes were observed. The stability constants for the 1:3 metal ion-N4bipy complexes equate to a theoretical separation factor, SF(Cm(III)/Eu(III)) ≈ 500. However, the low solubility of the HN4bipy ligand in nonpolar solvents typically used in actinide-lanthanide liquid-liquid extractions prevents its use as a partitioning extractant until a more lipophilic HN4bipy-type ligand is developed.

Publication Types