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. 07, 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 perhalocycloalkane selected from the group consisting of octafluorocyclobutane, hexafluoro-bis(trifluoromethyl)cyclobutane (1,2 and 1,3; cis and trans), 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane (cis and trans), 1,1,2,2-tetrachloro-3,3,4,4-tetrafluorocyclobutane, 1-chloro-1,2,2,3,3,4-hexafluoro-4-(trifluoromethyl)-cyclobutane, heptafluoro(trifluoromethyl)cyclobutane and chloroheptafluoro-cyclobutane from a mixture comprising (a) the perhalocycloalkane, (b) olefinic impurity and optionally (c) saturated fluorine-containing impurity selected from the group consisting of hydrochlorofluorocarbons, hydrofluorocarbons and mixtures thereof. The process involves (1) contacting the mixture with chlorine under conditions suitable for chlorinating the olefinic impurity, thereby converting the olefinic impurity to a saturated impurity containing at least one chlorine substituent and reducing the hydrogen content of the saturated fluorine-containing impurity (if present), and (2) separating said at least one perhalocycloalkane from the products produced during the chlorination of (1). Also disclosed is a process for producing n-decafluorobutane. The process involves contacting a mixture comprising octafluorocyclobutane (i.e., C-318) and 1,1,1,2,3,4,4,4-octafluorobutene-2 (FC-1318my) with chlorine under conditions suitable for converting the FC-1318my to 2,3-dichloro-1,1,1,2,3,4,4,4-octa-fluorobutane (i.e., CFC-318mbb); separating the C-318 from the CFC-318mbb; and reacting the CFC-318mbb with HF.