PROCESS OF WINNING OF SILVER FROM ITS ALLOYS Russian patent published in 1997 - IPC

FIELD: winning of silver with refining of silver alloys with simultaneous increased extraction of noble metal. SUBSTANCE: process includes dissolution of starting alloy in nitric acid in presence of ions of ammonium, separation of slag, treatment of heated solution of silver nitrate with ammonium hydroxide after sorption cleaning through anion-exchange resin, filtration of hydroxides of impurity metals. After electrolysis of silver from solution of silver nitrate electrolyte is returned for dissolution of alloy. EFFECT: single-stage winning of cathode silver, increased degree of extraction of silver without liquid waste and anode residue, refining of silver alloys with content of silver below 95% at commercial scale. 1 tbl