METHOD OF SEPARATING PLATINUM (II, IV) AND RHODIUM (III) IN AQUEOUS CHLORIDE SOLUTIONS Russian patent published in 2012 - IPC C22B11/00 C22B3/24 

FIELD: chemistry.

SUBSTANCE: method involves sorption of platinum (II, IV) and rhodium (III) through contact of the solution with a strongly basic anionite and then desorption from the anionite. Sorption is carried out from freshly prepared and held solutions on a Purolite A-500 anionite, containing a quaternary ammonium base as a functional group. Desorption from the anionite is carried out in two steps: at the first step - 24 hours after contact with 2M NH₄SCN solution or 2M KNO₃ solution to extract platinum. At the second step - after a further 24 hours with 2M HCl solution or 1M thiourea solution in 2M H₂SO₄ solution to extract rhodium.

EFFECT: simple and cheap method of separating platinum and rhodium, and possibility of realising the method not only in freshly prepared, but chloride solutions held for some time; the method is environmentally safe.

1 dwg, 3 tbl, 4 ex