Characterization of Basic Sites on Fine Particles of Alkali and Alkaline Earth Metal Oxides in Zeolites

Abstract To prepare basic zeolites, alkali metal oxides and magnesium oxide were attempted to introduce in the cavities of zeolite. The characterization of the resulting basic zeolites were performed by measuring the catalytic activities, TPD of adsorbed CO 2 , and X-ray absorption spectroscopy. Although simple cation-exchange failed to produce strong basic sites, the formation of alkali metal oxides and magnesium oxide resulted in strong basic sites in zeolites. To obtain strong basic zeolites, an ensemble of Mg and O to form MgO lattice is required for the zeolite containing MgO, but isolated species of metal oxides is sufficient for the zeolites containing alkali metal oxides.