Synthesis and Catalytic Performance of a Dual-Sites Fe–Zn Catalyst Based on Ordered Mesoporous Al2O3 for Isobutane Dehydrogenation

Abstract

Ordered mesoporous Zn/OMA-Fe materials were easily prepared via one pot evaporation induced self-assembly (EISA) method in combination with incipient wetness strategy. Dehydrogenation of isobutane to isobutene were carried out on these materials, the isobutane conversion of 50.7% and the yield of 37.8% were obtained over 13Zn/OMA-10Fe catalyst at 580 °C with 300 h−1 GHSV. The synthesized materials with large specific surface areas and uniform pore sizes were characterized by XRD, N2 adsorption–desorption, TEM, XPS, H2-TPR, Mӧssbauer and NH3-TPD. A portion of Fe species were highly dispersed on the support surface and others incorporated into Al2O3 frameworks, Zn species existed in the form of hexagonal ZnO phase. The total acidity of these catalysts was increased by the introduction of Zn, facilitating the conversion of isobutane. Moreover, the conversion of Fe species might play a major role in improving isobutene selectivity.