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:
Aug. 05, 2014
Filed:
Apr. 29, 2009
Armin Olbrich, Seesen, DE;
Matthias Jahn, Goslar, DE;
Juliane Meese-marktscheffel, Goslar, DE;
Ruediger Zertani, Goslar, DE;
Armin Olbrich, Seesen, DE;
Matthias Jahn, Goslar, DE;
Juliane Meese-Marktscheffel, Goslar, DE;
Ruediger Zertani, Goslar, DE;
H. C. Starch GmbH, Goslar, DE;
Abstract
A process for preparing a pure ammonium perrhenate includes producing a first aqueous suspension containing an ammonium perrhenate. A stoichiometric amount of a nitric acid is added to the first aqueous suspension so as to produce a second suspension. The second suspension is introduced into a cathode space of an electrolysis cell. The electrolysis cell is divided by a cation-exchange membrane into the cathode space and an anode space. The nitric acid is cathodically reduced to a nitrous acid in the cathode space by applying an electric potential. The nitrous acid is reacted with ammonium ions of the ammonium perrhenate so as to form an aqueous perrhenic acid. Potassium ions are removed from the aqueous perrhenic acid. At least a stoichiometric amount of ammonia is added to the aqueous perrhenic acid so as to produce the pure ammonium perrhenate.