Studies of the selective removal of micro-quantities of platinum(IV) ions from macro-quantities of model solutions of aluminium, copper, iron, nickel and zinc chloride on anion-exchangers of various types

Platinum has been widely applied as an industrial catalyst and consequently the recovery of noble metals from industrial wastes has become an economic issue. In the present studies, laboratory tests were undertaken to examine the selective removal of micro-quantities of platinum(IV) from I M solutions of aluminium, copper, iron, nickel and zinc chloride in 0.1 M hydrochloric acid using anion-exchangers containing tertiary amine group functions (Amberlite IRA-67 and Amberlite IRA-93) and polyamine group functions (Diaion CR-20). The values of the recovery factor [% R Pt(IV)] were determined for these anion -exchangers, as well as the sorption isotherms whose shape and type depended on the kind of aqueous phase employed and the phase contact time. In addition, the weight and volume distribution coefficients as well as the working and total ion-exchange capacities were calculated from the Pt(IV) breakthrough curves and various kinetic parameters were determined. The anion-exchanger Amberlite IRA-93 exhibited a maximum working capacity for Pt(IV) ions.