Synthesis of Propene from Ethanol: A Mechanistic Study

Physical mixtures comprising AgCeO2 and t-ZrO2 or MgO were employed as catalysts for the generation of propene from ethanol in the presence of water. The catalysts were characterized by means of several techniques such as X-ray diffraction, N2 physical adsorption, isopropanol conversion and ethanol to acetone Meerwein–Ponndorf–Verley (MPV) model reactions, NH3 temperature-programmed desorption, CO2 temperature-programmed desorption, and ethanol temperature-programmed desorption followed by diffuse reflectance infrared Fourier transform spectroscopy and mass spectrometry. Acid and strong basic sites, redox properties, and the capacity to conduct both water dissociation and MPV reduction are important characteristics for this reaction. Water is the oxidant agent; however, water may also affect the acidic–basic sites of the oxides, as demonstrated when MgO was used. The physical mixture comprising t-ZrO2 and AgCeO2 is active in the conversion of ethanol to propene, presenting the following steps. First, etha...