Catalytic dehydrofluorination of 1,1,1,3,3-pentafluoropropane to 1,3,3,3-tetrafluoropropene over fluorinated NiO/Cr2O3 catalysts.

Catalytic dehydrofluorination of 1,1,1,3,3-pentafluoropropane to 1,3,3,3-tetrafluoropropene was performed on a series of fluorinated NiO/Cr 2 O 3 catalysts. The NiO/Cr 2 O 3 catalysts were more active than the Cr 2 O 3 because the new acid sites provided by NiF 2 had higher turnover frequencies (9.43 × 10 −3 − 12.08 × 10 −3 s −1 ) than those on the Cr 2 O 3 (4.55 × 10 −3 s −1 ). Also, the NiO/Cr 2 O 3 was more stable than the Cr 2 O 3 due to its lower density of surface acid sites, which alleviated the coke deposition on the catalyst as evidenced by the Raman spectroscopic results. The kinetic results revealed that the15NiO/Cr 2 O 3 had much lower activation energy (63.6 ± 4.5 kJ mol −1 ) than the Cr 2 O 3 (127.6 ± 3.8 kJ mol −1 ). Accordingly, different reaction pathways on the two catalysts were proposed, which involved the cleavage of the C F and C H bonds on the surface acid and base sites, respectively. [ABSTRACT FROM AUTHOR]