Synthesis of Novel Solid Base of MgO Covered with Metal Oxides

The solid base catalysts of MgO covered with SiO2, Al2O3, TiO2, and ZrO2 were prepared by decomposition of the corresponding alkoxide over an Mg(OH)(2) surface in ethyl acetate solution followed by thermal decomposition. The acid-base properties of the prepared catalysts were estimated using 2-propanol decomposition activity and selectivity. The stability of catalysts for the aldol reaction of acetone against H2O was examined. The acid sites were generated on the MgO surface by covering with metal oxides. Base sites were formed when the MgO was covered with Al2O3. Catalysts made of MgO covered with more than 7 mol% Al2O3 showed sufficient stability against H2O as well as reusability.