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. 15, 2000
Filed:
Jul. 22, 1999
Sateria Salim, Amherst, NY (US);
Arthur Edward Holmer, Lewiston, NY (US);
Praxair Technology, Inc., Danbury, CT (US);
Abstract
This invention is directed to a method for producing UHP tungsten hexafluoride by introducing an amount of crude tungsten hexafluoride to an evaporating process for separation into an amount of tungsten hexafluoride-containing volatile impurities and an amount of non-volatile metallic impurities; passing the amount of tungsten hexafluoride-containing volatile residue to a gas phase adsorption process for separation into an amount of semi-crude tungsten hexafluoride product and an amount of hydrogen fluoride non-volatile residue; and passing the amount of semi-crude tungsten hexafluoride product to a sparging system using UHP helium for separation into a non-volatile UHP tungsten hexafluoride product.