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:
Nov. 18, 1980
Filed:
Apr. 18, 1979
Malcolm T Hepworth, Golden, CO (US);
John M Laferty, Wheatridge, CO (US);
Amax Inc., Greenwich, CT (US);
Abstract
An aqueous solution of at least one valuable oxyanion containing molybdenum, tungsten, vanadium, or uranium is refined to lower the content of contaminant anions such as PO.sub.4.sup.-3, SO.sub.4.sup.-2, NO.sub.3.sup.-, Cl.sup.-, ClO.sub.3.sup.-, and ClO.sub.4.sup.-, by subjecting the solution to electrolysis at a pH of from 0.5 to 4.0 between a cation-permselective membrane and an anion-permselective membrane having tertiary amine or quaternary ammonium anion exchange groups, to cause contaminant anions to pass from the solution into the anolyte. Ammonium molybdates, tungstates, vanadates, and uranates are formed from the thus-refined solution by subjecting it to a second stage of electrolysis at a pH of at least 7 between a cation-permselective membrane and an anion-permselective membrane to cause valuable oxyanions to pass from the solution into an anolyte which comprises an aqueous solution of ammonia and to form the desired ammonium compound.