Cr2O3 Catalysts for Fluorination of 2-Chloro-3,3,3-trifluoropropene to 2,3,3,3-Tetrafluoropropene

Cr2O3 catalysts were prepared by a precipitation method and tested for vapor phase fluorination of HCFC-1233xf (2-chloro-3,3,3-trifluoropropene) to HFC-1234yf (2,3,3,3-tetrafluoropropene) to investigate the effect of calcination temperature on the catalytic performance. The catalysts were characterized by XRD, Raman, NH3-TPD, and BET techniques. The results show, with increasing calcination temperature, the crystallite size of the catalyst increased while the surface acid sites decreased. It was found that the catalyst calcined at 500 °C exhibited the highest catalytic activity, with a HCFC-1233xf conversion of 63.3% and selectivies to HFC-1234yf and HFC-245eb (1,1,1,2,3-pentafluoropropane) of 59 and 38%, respectively, at a reaction temperature of 320 °C. Moreover, it was found that the carbon deposit on the surface was responsible for the deactivation of the catalyst during the reaction.