Enhanced Catalytic Performance of Fe-containing HZSM-5 for Ethane Non-Oxidative Dehydrogenation via Hydrothermal Post-Treatment

A facile strategy is applied to construct Fe supported ZSM-5 (Fe/HZ5-HTS) via hydrothermal post-treatment and applied to ethane non-oxidative dehydrogenation. Compared with Fe/HZ5-IWI prepared by incipient wetness impregnation, Fe/HZ5-HTS exhibits superior catalytic activity and long catalyst stability with 6000 minutes time-on-stream. An obvious volcanic curve is observed between the ethylene generation rate and Fe content, and 1.0Fe/HZ5-HTS exhibits the highest ethylene generation rate with 0.166 mmol C2H4 s(-1) g(Fe)(-1) over different Fe loading, which is twice as much as that of 1.0Fe/HZ5-IWI. According to various characterizations, isolated Fe3+ species and carburized Fe species are active sites, and the better catalytic performance over 1.0Fe/HZ5-HTS is ascribed to more disperse Fe species and exposing more Fe species in the surface. Besides, the lower ethylene desorption temperature and higher ethane desorption temperature over Fe/HZ5-HTS could suppress the overreaction of the ethylene to generate coke and increase ethane residence reaction time, resulting in less coke deposition and facilitating the catalytic performance.