Weßling Patrik, Maag Melina, Baruth Giana, Sittel Thomas, Sauerwein Fynn S, Wilden Andreas, Modolo Giuseppe, Geist Andreas, Panak Petra J
Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, 76021Karlsruhe, Germany.
Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 234, 69120Heidelberg, Germany.
Inorg Chem. 2022 Nov 7;61(44):17719-17729. doi: 10.1021/acs.inorgchem.2c02871. Epub 2022 Oct 23.
Novel hydrophilic ligands to selectively separate Am(III) are synthesized: 3,3'-([2,2'-bipyridine]-6,6'-diylbis(1-1,2,3-triazole-4,1-diyl))bis(propan-1-ol) (PrOH-BPTD) and 3,3'-([2,2'-bipyridine]-6,6'-diylbis(1-1,2,3-triazole-4,1-diyl))bis(ethan-1-ol) (EtOH-BPTD). The complexation of An(III) and Ln(III) with PrOH- and EtOH-BPTD is studied by time-resolved laser fluorescence spectroscopy. [ML] is found for both Cm(III) and Eu(III), while [ML] is only formed with Cm(III). Stability constants show a preferential coordination of Cm(III) over Eu(III) with PrOH-BPTD being the stronger ligand. The distribution of Am(III), Cm(III), and Ln(III) between an organic phase containing the extracting agent ,,','-tetra--octyl-3-oxapentanediamide (TODGA) and aqueous phases containing PrOH-BPTD is studied as a function of time and temperature as well as the TODGA, BPTD, and HNO concentrations. A system composed of 0.2 mol/L TODGA and 0.04 mol/L PrOH-BPTD in 0.33-0.39 mol/L HNO allows for selective Am(III) back-extraction into the aqueous phase while keeping Cm(III) and Ln(III) in the organic phase, marking PrOH-BPTD as an excellent complexant for an optimized AmSel process (Am(III) selective extraction).
合成了用于选择性分离镅（III）的新型亲水性配体：3,3'-（[2,2'-联吡啶]-6,6'-二基双（1-1,2,3-三唑-4,1-二基））双（丙-1-醇）（PrOH-BPTD）和3,,-（[2,2'-联吡啶]-6,6'-二基双（1-1,2,3-三唑-4,1-二基））双（乙-1-醇）（EtOH-BPTD）。通过时间分辨激光荧光光谱研究了An（III）和Ln（III）与PrOH-和EtOH-BPTD的络合情况。发现Cm（III）和Eu（III）均形成[ML]，而仅Cm（III）形成[ML]。稳定常数表明，对于PrOH-BPTD这种更强的配体，Cm（III）比Eu（III）具有优先配位作用。研究了镅（III）、锔（III）和镧系元素（III）在含有萃取剂N,N,N',N'-四辛基-3-氧杂戊二酰胺（TODGA）的有机相和含有PrOH-BPTD的水相之间的分配情况，作为时间、温度以及TODGA、BPTD和HNO浓度的函数。由0.2 mol/L TODGA和0.04 mol/L PrOH-BPTD在0.33 - 0.39 mol/L HNO中组成的体系能够将镅（III）选择性反萃取到水相中，同时使锔（III）和镧系元素（III）保留在有机相中，这表明PrOH-BPTD是优化的AmSel工艺（镅（III）选择性萃取）的优良络合剂。
