Speciation of protactinium(V) at tracer scale

Solvent extraction in the conditions of tracer scale chemistry was used to study protactinium(V) complexation with sulphate, chloride, oxalate and diethylene-triamine-pentaacetate. Extraction experiments were conducted using the chelating agent thenoyltrifluoroacetone (TTA) in toluene at constant ionic strength and temperature. Information on the species involved in partition equilibria relative to protactinium(V) complexation were deduced from a systematic study of the variations of distribution coefficient of Pa(V) as function of ligands, protons and TTA concentration