Reclamation of tungsten values from tungsten-thoria
US5819158A · kind A · utility
1Cited by
5References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 30, 1997 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | May 30, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A simple, cost effective method for reclaiming tungsten values from tungsten-thoria has been invented. The method involves reacting the tungsten-thoria with molten sodium hydroxide to form a soluble sodium tungstate and an insoluble residue of thoria, cooling the melt, dissolving the melt in water, and filtering to separate the insoluble residue of thoria from the dissolved sodium tungstate. The method resulting in substantially all of the tungsten values being reclaimed as sodium tungstate and acutely reducing the amount of radioactive material for disposal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.