Ligand structure and diluent nature in defining improved Am 3+ and Cm 3+ separation using diglycolamides: a combined solvent extraction and DFT study.

Separation of Am 3+ and Cm 3+ is one of the most challenging yet unavoidable steps in the back end of the nuclear cycle. Various ligands evaluated for Am/Cm separation have their own merits and demerits, and not a single ligand has been uniquely proposed for this purpose. In the present work, we evaluated N , N , N ', N '-tetra- n -octyldiglycolamide (TODGA) vis-à-vis N , N , N ', N '-tetra-2-ethylhexyldiglycolamide (T2EHDGA) in combination with a hydrophilic 2,6-bis(1,2,4-triazinyl)pyridine (SO 3 PhBTP) derivative in the aqueous phase for the separation of Am 3+ and Cm 3+ from nitric acid medium. The results showed that marginal selectivity for Am 3+ over Cm 3+ was observed with T2EHDGA in the presence of SO 3 PhBTP, which was attributed to the difference in the entropy change for their extraction from both the temperature-dependent liquid-liquid extraction and computational studies.