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:
Feb. 27, 2007
Filed:
Apr. 22, 2004
Raj P. Singh Gaur, Athens, PA (US);
Robert G. Mendenhall, Waverly, NY (US);
Raj P. Singh Gaur, Athens, PA (US);
Robert G. Mendenhall, Waverly, NY (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
A method for the dissolution and purification of tantalum ore and synthetic concentrates is described. The method preferably uses ammonium bifluoride as the fluoride source in place of the hydrofluoric acid used in the conventional methods. Other fluoride compounds such as NaF, KF, and CaFmay be used alone or in combination with ammonium bifluoride. The tantalum concentrate and fluoride source are combined with sulfuric acid to form a solution containing tantalum values and impurities. The tantalum values are then separated from the impurities by solvent extraction.