The Separation of Rhodium and Iridium. II. Chloridation and Chlorination of Iridium(III) and (IV)

Abstract The chloridation of iridium(III) chloro aquo complexes was studied at different aqueous HCl concentrations and temperatures to determine the optimum conditions which upon chlorination will lead to the most convenient method to produce an aqueous solution which only contains the [IrCl6]2− species required for very efficient separation of iridium from rhodium by separating agents like quaternary ammonium species. The interdependency of the two processes of chloridation and chlorination is indicated.