Dehydrogenation of Propane to Propylene over Ga2O3 Supported on Mesoporous HZSM-5 in the Presence of CO2

Dehydrogenation of propane to propylene over mesoporous HZSM-5 supported Ga2O3 catalysts in the presence of CO2 has been investigated, and compared with that of conventional HZSM-5 supported one. The initial activity of the catalysts descends while the stability and selectivity to propylene improve with increasing the Si/Al ratios of the support. The optimal Si/Al ratio is 240 for the propylene yield reaching 21.7% after reaction for 50 h. The introduction of the mesopores improves the activity as well as the stability of the catalyst, due to the better transport of the reactant and product molecules caused by its hierarchical structure. The selectivity for bulky products such as aromatics is also increased. The promoting effect of CO2 on the dehydrogenation reaction is observed.