A novel catalytic approach to the production of aromatics and ethene directly from methane （Ⅱ） ——TPSHR and characterization of the surface carbonaceous species on Mo/HZSM-5

摘要

＜正＞ The surface carbonaceous species on Mo/HZSM-5, which are formed from methane dehydrogena-non and aromatization, are characterized by temperature programmed oxidation （TPO）, 13 C CPMAS NMR and stud-red by Temperature programmed surface hydrogenation reaction （TPSHR）. According to their peak temperatures in the profile of TPO, three carbonaceous species of Cα, Cβ, and Cγ on Mo/HZSM-5 can be detected. Cα is the most ac-tise and Cβ second as far as the reaction with hydrogen is concerned. Cγ is inert and deposited on HZSM-5. Two types of surface carbonaceous species of Cσ and Cπ on used Mo/HZSM-5 can be identified by 13C CPMAS-NMR, whereas only Cσ on HZSM-5 Cσ is sp3 coordinated carbon and Cπ is sp2 coordinated.