Oxidative dehydrogenation of lower alkanes over metal incorporated MCM-41 catalysts

Abstract

A series of metal incorporated M-MCM-41 (M = Ce, Mo, and/or V) mesoporous materials were synthesized by the hydrothermal method. The synthesized mesoporous materials were characterized by the XRD, BET, TPR and EPR techniques. The extent of mesoporous structural ordering was evident from the XRD pattern of M-MCM-41. The catalytic properties of the metal containing MCM-41 catalysts were evaluated for oxidative dehydrogenation of propane and n-butane in a fixed-bed micro-reactor. The results showed higher activity in case of V-MCM-41 catalyst as compared to that of Mo-MCM-41 catalysts over a temperature range of 500–600 °C at atmospheric pressure. Cerium containing MCM-41 catalyst showed high selectivity (78%) for butadiene at moderate conversion of about 4%. The major products include ethylene, propylene and butanes. Propane conversion of about 20% with corresponding propylene selectivity of around 30% was obtained at 575 °C over V-MCM-41 catalyst. A small amount of H₂ besides CO_x was also produced during catalytic runs under the conditions of catalyst performance evaluation.