The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 27, 1983
Filed:
Mar. 23, 1981
Pierre Maurel, Aix-en-Provence, FR;
Francois Nicolas, Aix-en-Provence, FR;
Aluminium Pechiney, Lyons, FR;
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.