Imperial Chemical Industries Limited

Pravin K Dattani

John David Scott

Charles John Shields

Barry William Farrant

A method for regenerating a used fluorination catalyst such as a chromium-containing compound comprises contacting the used catalyst at a temperature of 300.degree. C. to 500.degree. C. with a mixture of an oxidizing agent, especially air, and hydrogen fluoride and optionally an inert diluent such as nitrogen, said mixture containing up to 30% of oxidizing agent on a molar basis. The method obviates chromium loss during regeneration/refluorination of spent catalyst and provides heated hydrogen fluoride for use directly in fluorination reactions.

Fluorination catalyst regeneration

Method for separating 1,1,1,2-tetrafluoroethane from a mixture thereof with chlorine-containing halogenated hydrocarbons such as HCFC's 1122, 124, 114, 114a and 133a which comprises adding an extraction agent to the mixture and extractively distilling the mixture in an extractive distillation zone from which HFA 134a containing less than 10 ppm of chlorinated contaminants is recovered. Suitable extraction agents include trichloroethylene, perchloroethylene, alpha-pinene and cyclohexane.

Growing community of inventors

Cheshire, United Kingdom

Pravin K Dattani