Electrorefined aluminium with a low content of uranium, thorium and rare earths
US5573574A · kind A · utility
4Cited by
1References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 13, 1995 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Jun 13, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for obtaining aluminum of purity above 99.998%. A liquid aluminum raw material is subjected to a fractional crystallization to obtain prepurified aluminum crystals in a yield of between 50 and 80% and a liquid aluminum portion of lesser purity. The prepurified aluminum crystals are subjected to a three-layer electrolysis process in which the uppermost layer comprises a cathodic purified aluminum layer. The aluminum of purity above 99.998% is removed from the uppermost layer at a yield of above 90%, the aluminum having a total rare earth content of less than 100 ppb and a total content of U+Th of less than 20 ppb.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.