TRLFS study on the complexation of Cm(iii) and Eu(iii) with SO₃-Ph-BTBP

Abstract

The complexation of Cm(iii) and Eu(iii) with a water soluble BTBP (sodium 3,3',3'',3'''-([2,2'-bipyridine]-6,6'-diylbis(1,2,4-triazine-3,5,6-triyl))tetrabenzenesulfonate, SO3-Ph-BTBP) is studied using time resolved laser fluorescence spectroscopy. For the complexation of Cm(iii) the influence of the medium (10(-3) M HClO4→ 0.5 M HNO3) is investigated in detail revealing important impacts of the applied medium (pH, ionic strength, anions) on the speciation and conditional stability constants. SO3-Ph-BTBP forms 1 : 2 complexes with Cm(iii) and Eu(iii). The conditional stability constants of [Cm(SO3-Ph-BTBP)2](5-) and [Eu(SO3-Ph-BTBP)2](5-) in 0.5 M HNO3 are determined to be log β02 = 7.3 ± 0.3 and log β02 = 5.4 ± 0.5, respectively. The difference of 1.9 orders of magnitude is in line with hydrophobic BT(B)P type ligands and shows that the selectivity is not affected by tuning the hydrophilicity using SO3-Ph-side chains.

Solvent Extraction and Fluorescence Spectroscopic Investigation of the Selective Am(III) Complexation with TS-BTPhen

“…As already observed by Wagner et al [20] , the increase of ionic strength destabilizes the mono Previous studies have shown the protonation of the free ligand to be the major contribution to the decrease of the conditional stability constants. [20] [27] and is attributed to the greater degree of preorganization of the BTPhen ligand.…”

“…The observed bathochromic shifts of the emission bands of the complex species are characteristic of the formation of a 1:1 and a 1:2 complex with a strong tetradentate N-donor ligand like TS-BTPhen [20,27,29] . Peak deconvolution was carried out, providing the spectra of the pure components shown in Figure 6.…”

“…[20] [27] and is attributed to the greater degree of preorganization of the BTPhen ligand. has a smaller effect on the final stability constant of the TS-BTPhen complex compared to that of SO 3 -Ph-BTBP.…”

“…[19] =200. [16,[20][21] The TODGA-TS-BTPhen based concept investigated in this work is a less complex alternative approach to the EXAm process and provides higher separation factors for Cm(III) over Am(III) compared to the AmSel process. Cm (5805 keV) using an Ortec Octête-pc eight chamber alpha measurement system equipped with PIPS detectors.…”

Spectroscopic and Computational Characterization of Diethylenetriaminepentaacetic Acid/Transplutonium Chelates: Evidencing Heterogeneity in the Heavy Actinide(III) Series

“…In contrast to the lanthanide (Ln) series, transplutonium chemistry studies are scarce, and most of the data have been acquired using tracer techniques or computational approaches . Among the trivalent actinides (An), Cm is undoubtedly the most studied, owing to its luminescence properties and the availability of its long‐lived isotope 248 Cm ( t 1/2 =3.49×10 5 years) to a handful of research institutions. A fair number of studies have also been performed on Am owing to its moderately long‐lived isotopes 241 Am ( t 1/2 =433 years) and 243 Am ( t 1/2 =7388 years).…”