Separation of Platinum Metals by Sorption on Chemically Modified Silica

The article reflects the latest achievements of the platinum metals school, established more than half a century ago at the Bolshakov Department of Chemistry and Technology of Rare Elements. The paper considers the physicochemical basis of the process of separating metals of the platinum group with similar properties by sorption on mesoporous silica grafted with nitrogen- and sulfur-containing organic molecules under dynamic conditions. The optimal conditions for the selective separation of Pd(II), Pt(IV), and Rh(III) ions in the process of sorption/desorption from model solutions of complex composition and their separation from accompanying ions of non-ferrous and noble metals have been identified. A scheme for processing technological solutions has been proposed and tested on a laboratory scale, ensuring the production of eluates of the specified metals with a target component content of 99%.