Zirconium and hafnium tetrachloride separation by extractive distillation with molten zinc chloride lead chloride solvent
US4737244A · kind A · utility
10Cited by
13References
8Claims
0Family size
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Key dates
| Filing date | Dec 18, 1986 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | Dec 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 -PbCl.sub.2 molten salt solvent, and preferably ZnCl.sub.2 -PbCl.sub.2 in a near eutectic or eutectic mixture. The extraction column is preferably run about 370.degree.-390.degree. C. at about one atomosphere and stripping is preferably done at 375.degree.-400.degree. C. utilizing an inert gas carrier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.