Preparation of 1,1,1,2-tetrafluoroethane by the vapor-phase catalytic reaction of 1,1,1-trifluoro-2-chloroethane with anhydrous hydrogen fluoride

1,1,1,2-Tetrafluoroethane was prepared in 97% selectivity by the vapor-phase catalytic reaction of 1,1,1-trifluoro-2-chloroethane with anhydrous hydrogen fluoride (AHF) over a metal fluoride catalyst (CrF3 and CoF2) supported on porous aluminum fluoride (PAF). The relationship between the crystalline phase transition of porous aluminum fluoride and temperature from 100 to 640°C was investigated by X-ray diffraction.