METHOD OF RECOVERING PLATINUM METALS FROM PLATINUM-CONTAINING CONCENTRATES Russian patent published in 2001 - IPC

FIELD: precious metal technology. SUBSTANCE: method includes oxidation firing, hydrochloric acid leaching of ashes resulting in transferring platinum metals into chloride solution for further recovery of platinum metals therefrom. Leaching of ashes is effected in presence of activating additive ensuring removal of passivating oxide film from the surface of platinum metals' grains, consumption of additive (hydrazine hydrochloride or sodium sulfite) being 5 to 10% of the weight of ashes. Method allows transferring platinum metals into chloride solution to be increased by 0.5 to 33% depending on particular metal. EFFECT: increased recovery of platinum metals and reduced their residual concentration in hydrochlorination precipitate. 3 cl, 1 tbl, 3 ex