Kinetics of hydration of autoclaved calcium sulphate hemihydrate

Abstract

Abstract The kinetics of the hydration of two sources of autoclaved calcium sulphate hemihydrate have been followed by an essentially isothermal method. Experiments have been carried out at different temperatures, water/powder ratios, and with added nuclei of crystallisation. A kinetic equation, based on the Avrami theory of crystallisation, and assuming the reaction to be diffusion‐controlled, has been developed and tested and found to be moderately successful under most conditions. The effects of variations of temperature and water/powder ratio are discussed.