Effect of mesopore structure of TNU-9 on methane dehydroaromatization

A series of micro-mesoporous molecular sieves TNU-9-x (TNU-9 Taejon National University no. 9) were prepared by a hydrothermal reaction method for non-oxidative aromatization of methane. The physical properties of the synthesized samples were characterized by XRD, SEM, TEM, BET, NH3-TPD and FT-IR spectroscopy. Characterization results suggested that the micro-mesoporous molecular sieves TNU-9-x exhibited similar geometrical shapes, but different pore properties with conventional microporous molecular sieve TNU-9. Catalytic tests indicated that Mo-TNU-9-20 showed excellent catalytic performance with a 14.9% conversion of methane and a 9.9% yield of aromatics. In addition, the catalytic stability of Mo-TNU-9-20 was better than the conventional microporous material Mo-TNU-9. The improved catalytic behaviour might be attributed to the generation of a secondary mesoporous system within the hierarchical pore materials.