SOLVENT-EXTRACTION OF IN(III) FROM CONCENTRATED HCL MEDIA WITH ADOGEN-364

The distribution equilibria of In (III) 0.1 mmol/dm(3) from HCl concen trated media (2.2-4 mol/dm(3)) with the commercial trialkylamine ADOGE N 364 dissolved in kerosene was studied. Due to the association proces ses that these type of extractants present in the organic phase, a pre liminary study was performed by means of a two phase potentiometric ti tration with the aim of determining the degree of association and the formation constants of the aggregates. The extraction of HCl is explai ned on the basis of the formation of ADGHCl and (ADGHCl)(2) species. W ith the data obtained the solvent extraction process of In (III) is di scussed. The presence of (ADGHCl)InCl3, (ADGHCl)(2)InCl3 and ((ADGHCl) (2))(2)InCl3 species in the organic phase allows to explain more satis factory the experimental results obtained. For all the proposed equili bria the corresponding equilibrium constant is determined from the num erical analysis of the data with the use of the Letagrop-Zeta or Letag rop-Distr programs.