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. 02, 1990
Filed:
Aug. 17, 1984
Achim M Kulling, Odenthal-Globusch, DE;
Helmut Steinhausen, Odenthal, DE;
Kronos Titan, GmbH, Leverkusen, DE;
Abstract
A process for the extensive removal of undesirable metal ions, particularly vanadium ions, in the course of the concentration of dilute iron(II) sulfate-containing sulfuric acid solutions. The sulfuric acid solutions are concentrated by the evaporation of water and the separation of iron(II) sulfate to a content of 60 to 70% by weight H.sub.2 SO.sub.4. According to the invention, the content of trivalent titanium in the solution is adjusted such that the content of trivalent iron does not exceed 0.1 g/l. The trivalent titanium may be added from the outside, if not already present in an adequate amount in the solution, or may be formed in situ from the tetravalent titanium present in the solution by the addition of a reducing agent. Prior to the final concentration, part of the iron may be precipitated and separated as iron(II) sulfate heptahydrate by means of preconcentration and cooling of the preconcentrated sulfuric acid solution.