Extraction of platinum(IV) from hydrochloric acid solutions by amine alamine 304 in xylene. Estimation of the interaction coefficient between PtCl62− and H+

Abstract

The extraction of Pt(IV) by Alamine 304 has been studied measuring the percentage of metal extraction as a function of different amine and metal concentrations and aqueous ionic strengths. Results indicated the formation of the species (R3NH+)2PtCl62− in the organic phase, the extraction reaction is exothermic (ΔH° = −1.9 kJ/mol). The formation constants vary linearly with the ionic strength; the interaction coefficient between PtCl62− and H+ was estimated using the Specific Interaction Theory. Further studies on the extraction of hydrochloric acid by the amine Alamine 304 are also presented.