Zirconium and hafnium tetrachloride separation by extractive distillation with molten zinc chloride calcium and/or magnesium chloride solvent

摘要

This is a molten salt extractive distillation process for separating hafnium from zirconium. It utilizes at least principally a ZnCl.sub.2 -- Ca/MgCl.sub.2 molten salt solvent, and preferably ZnCl.sub. 2 --Ca/MgCl. sub.2 in a near 95-15 mixture. The extraction column is preferably run about 380°-420° C. at about one atmosphere and stripping is preferably done at about 385°-450° C. utilizing an inert gas carrier.