Effect of Shape and Modification over ZSM-5 Catalyst on Methanol to Gasoline

Abstract

Fixed bed reactor was used to explore the catalytic performance of ZSM-5 catalysts with the forms of flake and strip in methanol to gasoline (MTG) reaction. The catalyst samples were characterized by XRD, BET and SEM. The strip ZSM-5 catalyst was modified by 0.4 Molar NaOH solution, which was denoted by TZSM-5/AT. The results show that ZSM-5 molecular sieves could be effectively dispersed to prevent carbon accumulation when extruded with binder. So the coke deposition resistance capacity of strip ZSM-5 has significantly enhancement comparing with flake ZSM-5. Mesoporous structure in strip zeolites formed after NaOH treatment, which could prevent coke formation and further improve catalyst life. The conversion of methanol remains above 80% over 140 hours on alkali-modified strip ZSM-5 operating at atmospheric pressure, 380°C and weight hourly space velocities (WHSV) of 1.5 h-1.