Patents

An improved process for preparation of 2H-heptafluoropropane comprising; (i) pre-treating the catalyst selected from a group consisting of metal oxides of chromium, aluminum or co-precipitated chromia-alumina impregnated with zinc chloride catalyst independently or in combination with nitrogen gas at a temperature ranging between 120 to 400 degree celcius for a period ranging between 12 to 24 hr, (ii) fluorinating the pre-treated catalyst with anhydrous hydrogen fluoride initially in presence of nitrogen gas as diluent till it reaches to 375 degree celcius and continued activation with anhydrous hydrogen fluoride at a temperature ranging between of 150 to 375 degree celcius for a period ranging between 15 to 50 hrs to obtain the fluorinated catalyst, (iii) co-feeding the mixture of hexafluoropropene and Anhydrous Hydrogen Fluoride (AHF) by vapor phase to the fluorinated-catalyst as obtained in step (ii) in continuous mode of reaction at a temperature ranging between 200 to 450 degree celcius with a contact time ranging between 5-80 seconds and purifying the product by cryogenic distillation.