Method for the preparation of difluoromethane
AssigneeULSAN CHEMICAL Co., Ltd.
InventorsKyung H. Nam, Doo C. Na, Dae S. Kim
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Abstract
There is disclosed a method for the preparation of difluoromethane wherein methylene chloride is reacted with. hydrogen fluoride in liquid phase, at a temperature of about 70.degree. to 90.degree. C. under a pressure of about 11 to 12 kg/cm.sup.2.g in the presence of antimony pentachloride. It is important that the concentration of quinquevalent antimony is maintained at a level of 85% or more with the feed mole ratio of hydrogen fluoride to methylene chloride ranging from about 2.0 to 2.3. Applicable to industrial scale, the method is operated in a batch system or in a continuous system. In addition, it exhibits superior conversion rate of the materials and production yield.
Claims3
A method for the preparation of difluoromethane, wherein methylene chloride is reacted with hydrogen fluoride in liquid phase at a temperature of from 70.degree. to 90.degree. C. and in the presence of a catalyst of antimony pentachloride (SbCl.sub.5) with the mole ratio of the catalyst to methylene chloride ranging from 0.05 to 0.17.
Dependencies are inferred from the claim text.