Effect of air addition on the catalytic performance of Pt-Sn/Al2O3 catalysts in propane dehydrogenation

The Al 2 O 3 -supported Pt-Sn catalysts were prepared utilizing an impregnation-reduction method and applied in the propane dehydrogenation in the presence of air. The addition of air, it not only provides a part of the heat required by dehydrogenation, but also improves the reaction conversion through the consumption of H 2 to H 2 O. Moreover, the operating conditions of the dehydrogenation process with air have been investigated. The reasonable operating conditions are recommended as follows: temperature=590 °C, GHSV=5200 h -1 , and C 3 H 8 : air: H 2 =4:5:4 (molar ratio). Under these conditions, the propane conversion and the propene selectivity attain 39.6% and 96.7%, respectively, simultaneously with the stable catalytic activity.