Rapid Synthesis of Self-Pillared ZSM-5 Zeolite Nanosheets with Enhanced Catalytic Performance in n-Octane Cracking

Investigating the synthesis of hierarchical ZSM-5 zeolite and its catalytic performance in the catalytic cracking of n-octane is significant for industrial production. In this work, self-pillared ZSM-5 zeolite nanosheets were prepared using a seed-assisted crystallization approach. The influence of crystallization time on the relative crystallinity, morphologies, pore characteristics, and acidity of a series of nanosheet-stacked ZSM-5 zeolite was investigated by using XRD, Raman, FT-IR, SEM, TEM, nitrogen physisorption, 27Al MAS NMR, NH3-TPD, and Py-IR characterization techniques. The self-pillared ZSM-5 zeolite synthesized with a crystallization time of 8 h exhibited enhanced catalytic performance in terms of both conversion and light olefin selectivity during n-octane cracking, which could be attributed to the synergistic effect of a suitable mesoporous structure and moderate acidity. Furthermore, the hierarchical self-pillared ZSM-5 zeolite exhibited improved anticoking stability because the shortened straight channel lengths can efficiently suppress the aromatic-based cycle, thus hindering the accumulation of the polycyclic aromatics.