Effect of Boron Species on Carbon Surface on Oxidative Dehydrogenation of Propane

Carbon catalysts for propane oxidative dehydrogenation (PODH) can potentially replace metal oxide catalysts due to their environmental friendliness (greenness) and excellent catalytic performance. Biomass carbon materials have the advantages of being abundant in variety, inexpensive, and easily available, but their catalytic selectivity is relatively poor in PODH. Therefore, we report here on a boron-doped sisal fiber carbon catalyst, which showed excellent selectivity of propylene in PODH, excluding the effect of surface-covered B2O3 on the catalytic performance by hot water washing. The carbon material exhibited the best catalytic performance with a load of 2%(mass) and a calcination temperature of 1100 °C. At a reaction temperature of 400 ℃, the conversion rate of propane was 2.0%, and the selectivity toward propylene reached 88.6%. The new chemical bonds formed by boron on the surface of the carbon materials had an important effect on the catalytic performance, as determined by XPS characterization. The B-O groups affected the catalytic activity by inhibiting the generation of electrophilic oxygen species, while the B-C content improved the selectivity toward propylene by changing the electron cloud density.