THE SEPARATION OF PLATINUM AND PALLADIUM BY SELECTIVE EXTRACTION OF H2PT(SCN)(6) AND H2PD(SCN)(4) USING A POLYTHF-IMPREGNATED FILTER

Platinum and palladium are known to form complexes with the thiocyanat e ion in solution. The isolation and separation of both platinum and p alladium as thiocyanate complexes is demonstrated by passing them thro ugh an organic-impregnated filter (OIF) prepared with polyTHF. Simulta neous extraction is performed by converting both metals into the extra ctable form. Sequential extraction is achieved by exploiting the diffe rence in the rates of formation for the extractable complexes of the t wo metals. The extraction of both metals is rapid with quantitative re coveries of platinum with flow rates as high as 600 mi min(-1) in smal l samples, while recoveries from larger volume samples were considerab ly lower. Once extracted, the metals can be removed from the OIF by co nversion to a non-extractable form with a high pH eluting solution. Th e rapid separation, isolation and preconcentration of both platinum an d palladium from aqueous samples is demonstrated. (C) 1998 Elsevier Sc ience B.V.