Dehydrogenation of propane over In 2O 3–Al 2O 3 mixed oxide in the presence of carbon dioxide

Abstract

Dehydrogenation of propane (PDH) to propylene in the presence of CO 2 was performed over binary In 2O 3–Al 2O 3 mixed oxides prepared by alcoholic coprecipitation. Synergistic effect of different composition on the catalytic performance has been observed. Characterization by X-ray diffraction and X-ray photoelectron spectroscopy revealed that the combination of the two components can result in significant modification in the surface properties and bulk dispersion of the In 2O 3 phase, which in turn leads to a higher reducibility of the In–Al–O composite. A correlation between the temperature-programmed reduction data and the PDH activity for In 2O 3–Al 2O 3 revealed that the creation of surface metallic indium species during the reaction is crucial for the dehydrogenation performance. The promoting effect of CO 2 on the yield of propylene has been attributed to a facilitation of simple dehydrogenation by its coupling with the reverse water gas shift reaction based on the results from temperature-programmed reaction of CO 2 with H 2.