Patent · US Expired

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

US4749448A · kind A · utility

9Cited by
13References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 18, 1986
Grant dateJun 7, 1988
Priority date
Expiry dateDec 18, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22B34/14
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

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.degree.-420.degree. C. at about one atmosphere and stripping is preferably done at about 385.degree.-450.degree. C. utilizing an inert gas carrier.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.