Abstract
A kinetic study was made on the hydrothermal reaction between lime and quartz, and in this reaction the effects of CaO/SiO2 ratio, particle size of quartz and added kaolin were discussed. Quartz powders with 1.5-2.5μm, 2.5-3.5μm and 3.5-5.0μm in particle radius were mixed with lime in molar ratio 1:0.8 and 1:1.2, pelletised and then autoclaved at 181°C for 0.5-24h.
Unreacted lime, unreacted quartz, combined alumina and combined water of the specimens were determined. The chemical composition of the products, rates of reaction and depths of the reacted quartz were calculated from the experimental data. It was found that the reaction of lime was controlled by dissolution and that the reaction of quartz was controlled by diffusion through the products layer arround each quartz grain.
When kaolin was added, the reaction ratio of quartz became low until all of the kaolin had reacted.
