Process for the purification of solutions containing alkali metal carbonate, sulphate, hydroxide or possibly hydrogen carbonate, and one at least of the metals vanadium, uranium and molybdenum
US4423013A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1981 |
| Grant date | Dec 27, 1983 |
| Priority date | — |
| Expiry date | Mar 23, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01G39/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Process for extracting molybdenum from aqueous solutions containing alkali metal carbonate, sulphate, hydroxide or hydrogen carbonate and, primarily, one at least of the metals belonging to the group formed by vanadium, uranium and molybdenum, in the form of alkali metal salts, and mineral and/or organic impurities, said solutions resulting from an ore attack cycle and being taken off after extraction of the metal being sought, in the form of a concentrate, wherein said solutions are caustified by the addition of a suitable amount of lime, converting the carbonate present into alkali metal hydroxide, a first precipitate is separated from the alkali metal hydroxide-rich liquor, said liquor is concentrated until the alkali metal hydroxide content is at most equal to 50%, to cause the production of a second precipitate formed by alkali metal sulphate and molybdate, which is solubilized in an aqueous recycle liquor, said re-dissolution liquor then being treated with sulphide ions and then acidified to give a pH-value of lower than 4.5, in order quantitatively to precipitate the molybdenum which is separated from the mother liquor, washed and dried for use as a source of molybdenum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.