Method for the dissolution and purification of tantalum pentoxide
US5635146A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1995 |
| Grant date | Jun 3, 1997 |
| Priority date | — |
| Expiry date | Nov 30, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method is disclosed for the dissolution and purification of tantalum pentoxide. The impure tantalum pentoxide is reacted with a potassium-containing compound to form potassium tantalate. The potassium tantalate is optionally slurried with sulfuric acid and dissolved in an HF medium. The solution is suitable for purification by conventional ion exchange or solvent extraction methods. A potassium fluorotantalate precipitate may also be formed by adding KCl to the solution. The fluorotantalate precipitate may be further processed into a pure tantalum pentoxide by suspending the precipitate in an aqueous solution optionally containing a chelating agent and adding ammonium hydroxide to form ammonium tantalum oxide which can then be converted to tantalum pentoxide by calcining at high temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.