Hafnium Production

Hafnium is produced together with zirconium. The following ways are used to separate hafnium and zirconium during zirconium concentrates processing, the first of which is zirconium nitrates solvent extraction by tributyl phosphate, or, zirconium rhodanides extraction by hexone (methyl isobutyl ketone, MIBK) and the second way is fractional crystallization of complex fluorides K₂[Zr(Hf)F₆]. The produced concentrates contain 20-96% form the amount zirconium + hafnium and 6-10% hafnium, respectively.

Hafnium metal sponge is obtained via HfCl₄ reduction by magnesium at 500-800°C; ingots - via HfF₄ reduction by calcium at 2000°C, sometimes in presence of I₂ and Zinc. Hafnium metal powder is produced via HfO₂ reduction by calcium at 1300°C or K₂[HfF₆] reduction by sodium at 800-900°C; also, electrolyzing the mixture of K₂[HfF₆], KC1 and NaCl at ~ 800°C or the fusion of HfF₄ and KCl at 700-800°C. Pure malleable Hafnium is produced by transport reaction
Hf + 2I₂ = HfI₄

being precipitated on an incandescent tungsten wire in the form of bars which then are molten down into big ingots in arc or electron-beam furnaces.