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:
Jan. 22, 1985
Filed:
Jul. 16, 1982
Pierre Maurel, Aix-en-Provence, FR;
Uranium Pechiney Ugine Kuhlmann, Paris, FR;
Abstract
A process for extracting arsenic from aqueous solution to be purified, in accordance with claim 1 of U.S. Pat. No. 2,404,601, which also contains alkali metal carbonate, sulphate, hydroxide or hydrogen carbonate, and which may also contain at least one of the metals vanadium, uranium and molybdenum, comprising caustification of said solutions by means of lime to convert the carbonates into alkali metal hydroxides, followed by separation of an alkali metal hydroxide-enriched liquor and a first precipitate essentially containing calcium carbonate which is subjected to a washing operation, concentration by evaporation of the mixture of the washing liquor of the first precipitate to produce a second precipitate which essentially comprises alkali metal sulphate, which is characterized in that, before the aqueous solution is caustified, the aqueous solution is treated by a magnesium compound in an amount at least equal to the stoichiometric amount required to cause precipitation of magnesium arsenate.