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:
Nov. 14, 2000
Filed:
Oct. 29, 1999
Allen Capron Sievert, Elkton, MD (US);
V N Rao, Wilmington, DE (US);
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process is disclosed for recovering at least one perfluorocycloalkane selected from the group consisting of octafluorocyclobutane, hexafluoro-bis(trifluoromethyl)cyclobutane (1,2 and 1,3; cis and trans), and heptafluoro(trifluoromethyl)cyclobutane from a mixture comprising (a) the perfluorocycloalkane, (b) olefinic impurity and, optionally, (c) saturated chlorine-containing impurity selected from the group consisting of chlorocarbons, hydrochlorocarbons, hydrochlorofluorocarbons, chlorofluorocarbons and mixtures thereof. The process involves (1) contacting the mixture with hydrogen in the presence of a hydrogenation catalyst under conditions suitable for converting at least a portion of the olefinic impurity to a saturated impurity containing at least one fluorine substituent less than the olefin impurity and reducing the chlorine content of at least a portion of the saturated chlorine-containing impurity (if present), and (2) separating said at least one perfluorocycloalkane from the products produced during the hydrogenation of (1).