| Abstract
| - Kinetic study of oxygen-free methane dehydrogenation and aromatization over Ru−Mo/HZSM-5was carried out in a fixed-bed differential reactor under atmospheric pressure. The reactiontemperature was varied between 873 and 973 K, and the methane feed fraction ranged from 50to 90% v/v. A plausible reaction pathway involved in oxygen-free methane dehydrogenation andaromatization over Ru−Mo/HZSM-5 was proposed. Different models based on Langmuir−Hinshelwood−Hougen−Watson reaction mechanisms were tested to correlate the kinetic data.Among these models, the one postulating that the surface dehydrogenation reaction of adsorbedmethane is rate-determining was successful in terms of physical likeliness (thermodynamic andkinetic parameters) and statistical goodness of fit. The activation energy, adsorption enthalpy,and entropy frequency were evaluated by means of Arrhenius or Van't Hoff relationships.
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