METHOD OF EXTRACTING IRIDIUM (III) FROM CHLORIDE SOLUTIONS Russian patent published in 2015 - IPC C22B11/00 C22B3/38 

FIELD: chemistry.

SUBSTANCE: method includes converting chloride complexes of iridium (III) into an iridium (IV) complex which is well extractable with tributyl phosphate by mixing a chloride solution of a platinum-group metal with a solution of hypochlorous acid in tributyl phosphate at 5-50°C. During the extraction process, the excess chloride ion in the form of molecular chlorine is simultaneously removed from the solution and iridium (III) is oxidised to iridium (IV). Extraction of iridium into the organic phase is 93-95%, and platinum, palladium, rhodium and ruthenium are virtually not extracted. Re-extractio of iridium from the organic phase is carried out using water or weakly alkaline aqueous solutions.

EFFECT: selective extraction of iridium from chloride solutions of platinum-group metals.

2 cl, 4 tbl, 4 ex