METHOD FOR EXTRACTION AND SEPARATION OF PLATINUM AND RHODIUM IN SULPHATE SOLUTIONS Russian patent published in 2013 - IPC C22B11/00 C22B3/24 

FIELD: metallurgy.

SUBSTANCE: proposed method involves conversion of platinum metals to actively sorbed sulphate-chloride form and sorption on strong-basic anion-exchange resin. At that, sulphate solutions of platinum and rhodium, which were prepared in advance and exposed during three months, are subject to conversion of platinum metals to active sorbed form by adding to them of a hydrogen chloride acid. Sorption is performed under dynamic conditions from obtained solutions on anion-exchange resin Purolite A-500, which contains tetradic ammonium base as a functional group with further desorption in two stages. At the first stage, solution 2M NaNO₃ is passed through anion-exchange resin to extract platinum, and at the second stage, solution 2 M HCl is passed through the above anion-exchange resin to extract rhodium. The method does not require any additional regeneration of a sorbent and is environmentally safe.

EFFECT: simplifying and cheapening both the conversion method of sulphate forms of platinum metals to chloride metals, and the extraction and separation process of platinum and rhodium in freshly prepared and old solutions.

2 cl, 1 tbl, 3 ex