Synthesis of Mo/TNU-9 (TNU-9 Taejon National University No. 9) catalyst and its catalytic performance in methane non-oxidative aromatization

Mo-modified catalysts of Mo/TNU-9 were prepared for the non-oxidative aromatization of methane. The effects of different Si/Al ratios, Mo loadings and temperatures on the catalytic performance of Mo/TNU-9 catalysts were also investigated. Furthermore, for comparison, Mo/ZSM-5 was synthesized for the same reaction. The physical properties and acidities of the samples were characterized by XRD (X-ray diffraction), SEM (scanning electron microscopy), BET (Brunauer–Emmett–Teller method) and IR (infrared) spectroscopy. The best conditions for methane aromatization with Mo/TNU-9 are as follows: Si/Al ratio = 50, 6 wt.% MoO3 loading, and reaction temperature = 973 K. Compared with Mo/ZSM-5, the Mo/TNU-9 catalyst showed both a higher conversion of methane and higher selectivity to benzene. In addition, the stability of Mo/TNU-9 was also better than that of Mo/ZSM-5. The superior catalytic behavior of Mo/TNU-9 may be attributed to its unique three-dimensional 10-member-ring channel structure with the presence of large 12-member-ring cavities.

Research highlights
► Mo-modified TNU-9 catalysts with various Si/Al ratios and Mo contents have been prepared.
► The best conditions for methane aromatization with Mo/TNU-9 are as follows: Si/Al ratio = 50, 6 wt.% MoO3 loading, and reaction temperature = 973 K
► Mo/TNU-9 catalyst showed a higher conversion of methane, a higher selectivity to benzene and better stability than Mo/ZSM-5.