Acid/base and surface features of pure phase magnesia powders

This paper reports data concerning the bulk and surface features of magnesia powders prepared by calcination of different precursor salts at increasing temperatures (873-1253K). The bulk characterization of the oxides has been obtained by X-ray diffraction, while the surface features have been investigated by means of N2 adsorption at subcritical temperatures and X-ray photoelectron spectroscopy. The acid/base features have been analysed by adsorption and step titration of dye indicators with known pK(b) values, in benzene.The powders appear to be composed of pure periclase, with a degree of crystallinity which is influenced by the nature of the precursor salt. The specific surface area and surface acid/base features of the samples are strongly dependent on both the nature of the precursor and the temperature of calcination. On the other hand, XPS data seem to be totally independent of the preparation route of the oxides, and acquire a general valence. Copyright (C) 1998 Elsevier Science B.V.