MANUFACTURE OF 1,1,1,2-TETRAFLUORO ETHANE amp; METHOD OF REDUCING AMOUNT OF 1,1,DIFLUORO-2-CHLORO ETHYLENE IMPURITY

摘要

is produced by the high temp. vapour phase reaction of a haloethane of formula (I): CX3CH2Y (I) (where each X = Br, Cl or F and Y = Br or Cl) with HF in the presence of a catalyst which is chromium oxide or is at least partially basic chromium fluoride. Used as coolant e.g. for freezing food, as aerosol propellant and porophore for expanded materials. It is obtd. in high purity.