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. 04, 1997
Filed:
Dec. 23, 1994
Jean-Michel Galland, Vernaison, FR;
Emmanuel Guiraud, Saint-Genis Laval, FR;
Jean-Pierre Schirmann, Paris, FR;
d'Elf Atochem S.A., , FR;
Abstract
The subject of the invention is a continuous process for the preparation of 1,1,1,2-tetrafluoroethane (134a) from 2-chloro-1,1,1-trifluoroethane (133a) and hydrofluoric acid in the gaseous phase in the presence of a chromium-based catalysts. According to the invention, the flow of gas leaving the reactor is subjected to a distillation in order to separate at the top a flow containing almost all the HC1 and at least 90% of the 134a produced by the reaction and at the bottom a flow containing at least 90% of the unconverted reactants (133a and HF), and the latter flow is recycled directly to the reactor, without any purifying operation.