Process for obtaining molybdenum as a useful product from molybdeniferous solutions containing alkali metal carbonate, sulphate, hydroxide or hydrogen carbonate and possibly uranium
US4432947A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 16, 1982 |
| Grant date | Feb 21, 1984 |
| Priority date | — |
| Expiry date | Jul 16, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for obtaining molybdenum as a useful product from aqueous solutions to be purified, according to claim 1 of French patent No. 2 404 601, which contain, besides said molybdenum, alkali metal carbonate, sulphate, hydroxide or hydrogen carbonate and which may also contain uranium, and inorganic and/or organic impurities, said solutions being treated at a temperature which is at most equal to the boiling temperature by means of lime to convert the alkali metal carbonate into hydroxide and to precipitate the insoluble calcium salts formed, then separating and washing the first precipitate which essentially contains calcium carbonate, from an alkali metal hydroxide-enriched liquor, which is concentrated by evaporation at the same time as the washing liquor of the first precipitate, to produce an alkali metal hydroxide content which is at most equal to 50%, to produce a second precipitate formed by a mixture of alkali metal molybdate and sulphate, characterized in that said solid mixture is dispersed in an acid aqueous liquor which is heated at from 120.degree. C. to 250.degree. C. under pressure to cause precipitation of anhydrous Mo0.sub.3 which is subsequently separated from …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.