A NEW EXTRACTION CHROMATOGRAPHY RESIN CONTAINING KLÄUI LIGANDS FOR APPLICATION IN ACTINIDE SEPARATIONS

Abstract An extraction chromatography resin containing the anionic ligand (η5‐pentamethylcyclopentadienyl)tris‐(diethylphosphito‐P)cobalt(III), Cp * Co[P(O)(OEt)2]3 − (1Et) has been prepared. The resin consists of 1 wt% 1Et on Amberlite® XAD‐7. This resin strongly sorbs Am3+ and Pu4+. The sorption of these ions decreases with increasing nitric acid concentration, but this effect is more pronounced for Am3+. This allows for convenient separation of Am3+ from Pu4+ by simple adjustments in the HNO3 concentration. The tripodal geometry of 1Et disfavors the complexation of UO2 2+, so sorption of U(VI) by the 1Et‐containing resin is weak. An analogous resin containing Cp * Co[P(O)(OPr)2]3 − (1Pr) shows similar Pu4+ sorption behavior.