The study of the PtCl62- concentration with reversed micelles as a function of the acid-salt content of the feed

It is shown that the acidity and the electrolyte concentration of the feed can control the solubilizing capacity and size of the micelles in extraction systems, which may be used to improve the PtCl62- concentration. The increase in HCl concentration increases the recovery but decreases the concentration, because of the formation of large micelles of a high solubilizing capacity. The addition of Na2SO4. to the acid solutions improves the concentration and recovery, the size and the capacity of the micelles being decreased. An increased concentration of H+ and Cl- ions and a decreased concentration of Na+ and SO42- ions in micelles relative to their concentration in the feed was established. The micellar pseudophase composition points to the formation in the micelles of a double electric layer (DEL) capable of exchanging its counterions for PtCl62-. Impregnation into reversed micelles of an anionic oil-soluble surfactant (bis(2-ethylhexyl)sodium sulfosuccinate (AOT)) compensates the surface charge of the micelle and depresses the extraction.