MECHANOCHEMICAL REACTIONS OF HYDRATED OXIDES

Thermodynamic calculations have shown that chemical reactions in mixtu res of hydrated oxides are more advantageous than those in anhydrous o xide mixtures. Mechanochemical reactions of calcium oxide with hydrate d and anhydrous aluminum, silicon, titanium, vanadium, and tungsten ox ides are investigated experimentally. It was shown that the reaction r ate is correlated with the thermodynamic reaction potentials, and also with differences in the proton affinity of the oxides. The influence of water additives on the synthesis rate was investigated. It was foun d that the reaction rate goes through a maximum in its dependence on w ater content. (C) 1994 Academic Press, Inc.