SEPARATION OF ZIRCONIUM AND HAFNIUM USING ANION-EXCHANGE RESINS. PART III. RESOLUTION OF HAFNIA CONCENTRATES

The anion-exchange method of separating hafnium from zirconium previously reported for resolving a naturally occurring mixture (Hf/Zr, 3%) was modified and applied to hafnia concentrates. A complete separation of the two constituents was achieved on a suifate exchanger by elution with dilute sulfuric acid. About 50% of the eluting acid (pre-breakthrough volume) can be recycled. Gram loads of hafnia concentrates were found to give 93 to 95% recovery of pure hafnia (Zr/Hf, < 0.1%) on 1.5 x 120 cm resin columns. (auth)