Ai. Bulavchenko et al., The study of the PtCl62- concentration with reversed micelles as a function of the acid-salt content of the feed, J PHYS CH B, 104(20), 2000, pp. 4821-4826
It is shown that the acidity and the electrolyte concentration of the feed
can control the solubilizing capacity and size of the micelles in extractio
n systems, which may be used to improve the PtCl62- concentration. The incr
ease in HCl concentration increases the recovery but decreases the concentr
ation, because of the formation of large micelles of a high solubilizing ca
pacity. The addition of Na2SO4. to the acid solutions improves the concentr
ation and recovery, the size and the capacity of the micelles being decreas
ed. An increased concentration of H+ and Cl- ions and a decreased concentra
tion of Na+ and SO42- ions in micelles relative to their concentration in t
he feed was established. The micellar pseudophase composition points to the
formation in the micelles of a double electric layer (DEL) capable of exch
anging 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 extra
ction.