Process for the production of difluoromethane
AssigneeSFR Limited
InventorsRajasekaran Ramanathan, Rajdeep Anand, Anurag Jain, Jampani Madhusudana Rao
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Abstract
A process for vapor phase fluorination of methylene chloride with anhydrous hydrogen fluoride (AHF) in the presence of a coprecipitated chromia-alumina impregnated with zinc salt as catalyst, removing HCl and heavier components by distillation, subjecting HFC-32 rich cut to a further step of fluorination in the presence of a fluorination catalyst.
Claims11
A process for the preparation of difluoromethane (HFC-32) by vapor phase fluorination of methylene chloride with anhydrous hydrogen fluoride (AHF) in the presence of a coprecipitated chromia-alumina impregnated with zinc salt as catalyst at a temperature ranging from 225-375° C. and contact time not exceeding 20 seconds, removing HCI and heavier components by distillation, subjecting HFC-32 rich cut to a further step of fluorination in presence of fluorination catalyst to convert chlorofluoromethane HCFC-31, an intermediate formed along with HFC -32, to HFC-32 thereby reducing the concentration of HCFC 31 in HFC-32 rich cut to obtain pure HFC-32.
Dependencies are inferred from the claim text.