Hierarchical Porous ZSM-5 Zeolite Synthesized by in situ Zeolitization and Its Coke Deposition Resistance in Aromatization Reaction

摘要

Hierarchical ZSM-5 zeolites with micro-, meso- and macroporosity were prepared from diatomite zeolitization through a vapor-phase transport process on solid surfaces. The aromatization performance of the catalysts was in- vestigated on a fixed bed reactor by using FCC gasoline as feedstock. The crystal phase, morphology, pore struc- tures, acidity and coke depositions of the hierarchical ZSM-5 zeolites were characterized by means of X-ray diffrac- tion （XRD）, scanning electron microscope （SEM）, N2 adsorption/desorption, Fourier transform infrared （FT-IR） and thermogravimetry-mass spectrogram （TG-MS）, respectively. The results show that the prepared hierarchical ZSM-5 zeolite possesses excellent porosity and high crystallinity, displaying an improved aromatization performance and carbon deposition resistance due to its meso- and macroporous structures.