Recovery of tungsten from ammoniacal solutions
US4626425A · kind A · utility
2Cited by
1References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1985 |
| Grant date | Dec 2, 1986 |
| Priority date | — |
| Expiry date | Feb 25, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method is disclosed for recovering tungsten from a relatively dilute ammoniacal tungsten solution. The method involves adding hexamethylenetetramine to the tungsten solution in an amount sufficient to form a hexamethylenetetramine complex then adjusting the pH to from about 1.0 to about 2.0 with a mineral acid to form a precipitate of the complex containing at least about 99% of the tungsten, and separating the precipitate from the resulting mother liquor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.