SINTERING AND SULFATION OF CALCIUM SILICATE CALCIUM ALUMINATE

The reactivity of a solid at high temperature can be greatly retarded by physical changes occurring in its pore structure due to sintering. The nature of that effect was studied with calcium silicatecalcium aluminate reacting with SO2between 665 and 800 °C, where sintering of this material progresses rapidly. The isothermal kinetics of the sintering and sulfation processes were measured independently as a function of the specific surface area of the solid. The rates of both processes were increased by the presence of water vapor in the gas as well as by higher temperatures. A combined sinter/sulfation model, based on the parameters evaluated independently, is in qualitative agreement with sulfation rates observed when both processes occur simultaneously. © 1990, American Chemical Society. All rights reserved.