METHOD OF SEPARATING METALS FROM PLATINUM, PALLADIUM, RHODIUM Pt-Pd-Rh Russian patent published in 2019 - IPC C22B11/00 C22B3/44 C22C5/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to hydrometallurgy of platinum metals, specifically to regeneration and separation of platinum metals from spent materials of alloy Pt-Pd-Rh. Alloy is dissolved to produce solution of chlorocomplexes H₂PtCl₆, H₂PdCl₄, H₃RhCl₆. Platinum is obtained from obtained solution in form of ammonium hexachloroplatinate (NH₄)₂PtCl₆ by preparing aqueous pulp and treating pulp with carbon monoxide CO at atmospheric pressure and t=25–70 °C. When the system achieves the redox potential (ORP) value of 250 mV, the treatment is terminated, the precipitated palladium and platinum precipitate is separated from the solution, and the filtrate is continued to be treated with carbon monoxide CO under the same conditions until the ORP = 0 mV, after which the precipitate is separated and calcined at 1,000 °C to obtain high purity platinum. Solutions obtained from isolation of (NH₄)₂PtCl₆ and platinum, mixed and treated with carbon monoxide CO at atmospheric pressure and room temperature until the ORP value of system is 0 mV. Separated precipitate of palladium powder is separated from solution, after which remaining solution is treated with alkali to pH≥8 value with separation of rhodium in form of fine powder, which after boiling is separated from solution.

EFFECT: method increases degree of separation and extraction of noble metals with high degree of purity.

1 cl, 1 tbl, 3 ex