Structural and morphological features of MgO powders. The key role of the preparative starting compound

The present paper reports data concerning magnesia samples obtained by calcination of different precursor salts at different increasing temperatures (873-1253 K). The oxides are characterized by x-ray diffraction, scanning electron microscopy, and N2 adsorption at subcritical temperatures. The samples appear to be composed, at any temperature, of pure periclase with a degree of crystallinity which increases with the temperature of calcination. Morphologically, the products have the shape either of lamellas or of cubes of variable dimensions, depending on the nature and route of preparation of the precursor salts. The variation of the specific surface area and the degree of porosity with the nature of the precursors and the temperature is discussed.