Anion exchange of metal complexes-XV⁽¹⁾. Anion exchange and amine extraction of lanthanides and trivalent actinides from chloride solutions

The lanthanide and trivalent actinide complex species existing in concentrated aqueous chloride solutions were ascertained from anion exchange and amine extraction data. The dependence of the anion exchange distribution coefficients on the crosslinking of the resin and on the acidity of the solutions leads to the species MCl₄^- in the resin, and the chloride concentration dependence leads to MCl₂⁺ as the major species in solution. The dependence of the distribution coefficients with amines on amine concentration, acidity and chloride concentration leads also to MCl₂⁺ in the aqueous phase, in accord with the anion exchange data. For Am(III), the species in the organic phase is probably LiA₂AmCl₆, where A⁺ is the result of the dissociation of one chloride ion from an amine hydrochloride aggregate.