Supported indium oxide as novel efficient catalysts for dehydrogenation of propane with carbon dioxide

In2O3-MOx binary mixed metal oxide catalysts (M: Al, Zn, Zr, Ti, Fe, Mg, Si, and Ce) prepared by a coprecipitation or sol-gel method have been tested for the dehydrogenation of propane to propylene in the presence of carbon dioxide. Several techniques including N-2 adsorption/desorption, X-ray diffraction, H-2-temperature-programmed reduction and X-ray photoelectron spectroscopy were applied to characterize the physicochemical properties of the as-synthesized materials. Catalytic tests showed that all In-containing samples were active in the CO2-promoted dehydrogenation of propane with good propylene selectivity. Among the In2O3-MOx catalysts tested, the In2O3-Al2O3 sample containing a 20 mol% indium content showed the highest dehydrogenation activity with superior long-term stability. The specific interaction between In2O3 and Al2O3 leading to a high component dispersion is suggested to play a key role in regulating the redox and structural properties of surface indium species, which makes the In2O3-Al2O3 composite highly active and stable for the reaction. (C) 2010 Elsevier B.V. All rights reserved.