Facile One-Pot Synthesis of ZSM-5 Aggregates with Inter- and Intra-Crystalline Mesopores for Methanol to Gasoline Conversion

Abstract

ZSM-5 aggregates consisting of superfine and hierarchical nanocrystals (combined with micropores and intra-crystalline mesopores) with an average size of 30 nm were prepared through one-pot synthesis with the assistance of anionic polyacrylamide (APAM). The resultant zeolites (AHN-ZSM-5) were characterized by XRD, ICP-OES, SEM, TEM, BET, NH3-TPD, Py-IR, and TG analyses and evaluated in the methanol to gasoline (MTG) reaction. Characterization results show that the hierarchical ZSM-5 aggregates possessed two kinds of mesopores, namely inter- and intra-crystalline mesopores. The amount of APAM considerably influenced the mesoporosity and textural properties of AHN-ZSM-5 zeolites. With the addition of APAM in the synthesis, the AHN-ZSM-5 zeolites exhibited large mesopore volume, large external surface area, and appropriate acidity. When applied in the MTG reaction, AHN-ZSM-5 demonstrated a catalytic lifetime that was 1.6 times longer than that of conventional ZSM-5 synthesized in the absence of APAM.