FORMATION OF SURFACE BASICITY THROUGH THE DECOMPOSITION OF ALKALI-METAL NITRATES ON GAMMA-AL2O3

The gamma-Al2O3-supported alkali metal nitrate samples with various lo adings were prepared by the incipient wetness impregnation method. Dif ferential thermal analysis (DTA), X-ray diffraction (XRD), and magic-a ngle-spinning (MAS) Na-23 and Al-27 NMR were conducted regarding the d ecomposition of supported nitrates and the chemical states of alkali m etals on gamma-Al2O3. The surface basicity and acidity of these sample s evacuated at different temperatures were determined by microcalorime tric adsorption of CO2 and NH3, which were correlated to the states of alkali metals, as revealed by the various physical characterizations.