METHOD OF COMBINED RECOVERY OF PLATINUM AND RHENIUM FROM SPENT PLATINUM-RHENIUM CATALYSTS Russian patent published in 2001 - IPC

FIELD: processing of spent platinum-rhenium catalysts based on Al₂O₃. SUBSTANCE: method includes acid leaching of platinum-rhenium catalysts with application of DC with density of 25-30 A/sq.dm for 7.5-8 h in hydrochloric-surface acid solution with simultaneous cathode precipitation of Pt and Re in ratio S:L= 1:(10-20). Process temperature is 65-70 C. In this case, catalyst base in the form of aluminum oxide is not practically dissolved and platinum and rhenium are transferred into solution in the form of PtCL26

^- and ReO-4, due to active chlorine obtained on anode, and then precipitated on cathode as pure metals. To reduced expenses, process may be realized by step, i. e. ate definite conditions and current density of 10 A/sq.dm for 6 h, and then for 2 h at current density of 30 A/sq.dm. The method provides for recovery of Pt up to 99% and Re, up to 93%. EFFECT: exclusion of multistage operations of platinum and rhenium recovery from spent catalysts and their subsequent refining, reduced losses of valuable metals. 6 cl, 2 tbl, 3 ex