HYDROFLUOROCARBON PRODUCTION USING HEAT CARRIERS IHYDROFLUOROCARBON PRODUCTION USING HEAT CARRIERS IN HIGH TEMPERATURE HYDROGENOLYSIS N HIGH TEMPERATURE HYDROGENOLYSIS

摘要

A process is disclosed for producing a saturated hydrofluorocarbon (cyclic or acyclic) of the formula CnHaFb (where n is 1-6, a is 1-7 and b is 2-13) by reacting at least one saturated starting material having the same carbon structure as said saturated hydrofluorocarbon and the formula CnHcXdFb (where c is 0-3, and d is 1-4, and each X is independently Cl or Br) with hydrogen in a reaction vessel at a temperature of from about 350 to 700 °C and a pressure of from about 101 kPa to about 7000 kPa for a time sufficient to produce said saturated hydrofluorocarbon. The process is characterized by feeding to the reaction vessel, the starting material and, for each mole of total carbon-chlorine and carbon-bromine bonds in the starting material (a) at least 0.5 moles of hydrogen, and (b) at least about 2.5/J moles of a saturated heat carrier compound which has a molar heat capacity greater than the heat capacity of hydrogen and has the formula CmHzFy (where J is the ratio of the molar heat capacity of the heat carrier compound to the molar heat capacity of hydrogen at the reaction temperature, m is 1-4, z is 0-8 and y is 0-10); and reacting the starting material with the hydrogen in the reaction vessel in the presence of the heat carrier compound. The moles of hydrogen plus J times the moles of the heat carrier compound fed to the reaction vessel is at least about 3 times the moles of carbon-chlorine and carbon-bromine bonds in the saturated starting material fed to the reaction vessel, and less than 10 % of the fluorine from the carbon-fluorine bonds fed to the reaction vessel is converted to HF.