Distribution coefficients of Pt, Ir, Pd and Rh in the systems Dowex 1 [Br−]−HBr plus 0.0035M bromine and Dowex 1 [Br−]−HBr plus 2% N2H4·HCl, were determined with the aid of radioactive tracers by batch equilibration for the resins of nominal cross-linking 2,
4 and 8, respectively. Column experiments showed that Dowex 1X4 should be used for separations because of the favourable dynamics
of the column process. Elution conditions for the quantitative separation of both trace and milligram amounts of Ir−Pt, Rh−Pt,
Pd−Pt and Ir−Pd−Pt mixtures are given. Some data on the effect of temperature upon the quality of separation are also presented.