US 5,334,787 A · Process for the manufacture of pentafluoroethane

Abstract

An improved process for the manufacture of CF.sub.3 CHF.sub.2 by contacting 1,2-dichloro-1,1,2-trifluoroethane (CClF.sub.2 CHClF) or 1-chloro-1,1,2,2-tetrafluoroethane (CHF.sub.2 CClF.sub.2) or mixtures of CF.sub.3 CHCl.sub.2 and CClF.sub.2 CHClF or mixtures of CF.sub.3 CHClF and CHF.sub.2 CClF.sub.2 with HF in the presence of a Cr.sub.2 O.sub.3 catalyst prepared by pyrolysis of ammonium dichromate, the reaction being conducted under controlled conditions whereby the production of CF.sub.3 CHF.sub.2 is maximized, and the formation of chloropentafluoroethane (CF.sub.3 CClF.sub.2) and other perhalo derivatives is minimized. The subject hydrogen-containing compound is useful as a blowing agent, propellant, refrigerant, fire extinguishing agent, or sterilant carrier gas.

Claims13

Dependent claims

A process for the preparation of CF.sub.3 CHF.sub.2 comprising:

(a) contacting HF with at least one reactant comprising a material selected from the group consisting of CF.sub.3 CHCl.sub.2, CClF.sub.2 CHClF, CF.sub.3 CHClF, and CHF.sub.2 CClF.sub.2, in the gas phase in the presence of a solid Cr.sub.2 O.sub.3 catalyst at a temperature of about 300.degree. to 370.degree. C. and an HF/reactant mole ratio of about 2/1 to 10/1 for a time of about 10 to 100 seconds to form a product stream comprising at least about 50 mole % CF.sub.3 CHF.sub.2, and less than about 2 mole % CF.sub.3 CClF.sub.2 ;
and thereafter,
(b) separating and recovering CF.sub.3 CHF.sub.2 from the product stream.

Dependencies are inferred from the claim text.

Process for the manufacture of pentafluoroethane

Life of this patent

Process for the manufacture of pentafluoroethane

Life of this patent

Abstract

Claims13