Catalytic non-oxidative propane dehydrogenation over promoted Cr-Zr-Ox: Effect of promoter on propene selectivity and stability

Abstract

The effect of Cs-, Ca- and P-containing promoters for binary Cr-Zr-Ox on propene selectivity and catalyst stability with time-on-stream in the non-oxidative propane dehydrogenation was elucidated. Large improvements in this catalytic performance were achieved when combining Cs and P promoters. They were suggested to partially block dehydrogenation sites resulting in the isolation of the latter. As a reason thereof, coke formation through propene oligomerization is inhibited in favor of propene desorption from the catalyst surface. The present catalysts achieved ~30% conversion of propane at WHSV (C3H8) of 5.89 h-1 at 550 °C in comparison with 20% over K-CrOx/Al2O3. The selectivity to propene was determined to be ~94%.