[en] A study has been made to find the optimum batch adsorption and elution zirconium and hafnium with a strongly acidic cation exchanger (Dowex 50w-x 8). It was found that zirconium is adsorbed well at pH above 4.3 and precipitated at pH about 5, the excess of 8-hydroxyquinoline-5-sulfonic acid (sulfoxin) as a chelating agent lower the adsorption efficiency. The elution with 0.5 N sulfuric acid, 11% zirconium can be removed whereas 3% hafnium is eluted, and 8% hafnium or 11% zirconium is eluted with 2 N sulfuric acid. It may be separated zirconium from hafnium when elution with 0.5 N, following with 2 N sulfuric acid