ZnO supported on Silicalite-1 as an efficient catalyst for isobutane dehydrogenation to isobutene assisted by CO2

The ZnO catalysts supported on Silicalite-1 zeolite with a Zn content between 1% and 9% were synthesized by an incipient wetness method. These catalysts were characterized by XRD, N-2 adsorption, SEM, TEM-EDX, UV-vis, DRIFTS and NH3-TPD. They were found to be effective for isobutane dehydrogenation to isobutene assisted by CO2, and the catalytic activity is well correlated with the amount of acid sites which are primarily originated from the dispersed zinc oxide species. Silicalite-1 -supported ZnO is far more active than SBA-15-supported one with the same Zn content. The catalytic stability is improved remarkably by introducing CO2 to the feed gas.