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:
Mar. 16, 2004
Filed:
Feb. 06, 2003
Leo Ernest Manzer, Wilmington, DE (US);
Frank Julian Weigert, Wilmington, DE (US);
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A method is disclosed for increasing in a composition the mole fraction of a compound selected from the group CF CHCl , CF CHF and CF CHClF relative to the total mole fraction of the other two compounds of the group. The method comprises (a) providing a gaseous composition comprising at least one compound of said group provided that (i) if the selected compound is either CF CHCl or CF CHF , said gaseous composition comprises CF CHFCl and the mole fraction of the selected compound relative to the other two compounds in said gaseous composition is less than its equilibrium amount at 50° C., and (ii) if the selected compound is CF CHFCl, said gaseous composition comprises both CF CHCl and CF CHF and the mole fraction of the selected compound relative to the other two compounds in said gaseous composition is less than its equilibrium amount at 500° C.; (b) contacting said gaseous composition with a catalyst selected from the group of catalysts consisting of catalysts comprising chromium as an oxide, as a halide or as a halided oxide, in a valence state of three to six, and supported catalysts containing at least one metal selected from cobalt, copper, iron, manganese, nickel and zinc for a time sufficient to provide substantial equilibrium between the three compounds having said formula; and (c) providing during said catalyst contact a temperature within the range of about 50° C. to 500° C. at which the mole fraction of the selected compound relative to the other two compounds increases.