Concentration effect of Cs+ additive on the γ-Al2O3-to-α-Al2O3 phase transition

The effect of Cs+ additive on the gamma-Al2O3-to-alpha-Al2O3 phase transition was investigated as a function of the Cs+ concentration by powder X-ray diffraction and specific surface area (S-A) measurements. The addition of Cs+ increasingly retarded the gamma-to-alpha phase transition with increasing Cs+ concentration, reading a maximum at 5% addition, at which the transition temperature was increasing by about 200 degrees C. This Cs+ concentration corresponds to an amount of cation which would almost fully cover the surface of the gamma-Al2O3 grains. (C) 2000 Elsevier Science B.V. All rights reserved.