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:
Jul. 10, 2012
Filed:
Jan. 29, 2008
Viktor Stoller, Bad Harzburg, DE;
Michael Erb, Salzgitter, DE;
Juliane Meese-marktscheffel, Goslar, DE;
Michael Lohse, Goslar, DE;
Klaus-jürgen Marschall, Goslar, DE;
Frank Schrumpf, Goslar, DE;
Viktor Stoller, Bad Harzburg, DE;
Michael Erb, Salzgitter, DE;
Juliane Meese-Marktscheffel, Goslar, DE;
Michael Lohse, Goslar, DE;
Klaus-Jürgen Marschall, Goslar, DE;
Frank Schrumpf, Goslar, DE;
H.C. Starck GmbH, , DE;
Abstract
The invention is directed to a process for the continuous preparation of ammonium paratungstate hydrate by back reextraction of a tungsten-laden organic phase with an ammonia-containing aqueous solution in a mixer-settler apparatus. The reextraction is carried out at an NH:W molar ratio of from 0.83 to 1.30, and a volume feed ratio of the tungsten-laden organic phase to the ammonia-containing aqueous solution of from 5 to 25. The above crystalline is in high purity and in high yield. The production method can be carried out in a simple and energy-efficient manner.