Non-isothermal decomposition kinetics of alkaline earth metal carbonates

Abstract

The kinetics of thermal decomposition of four synthetic alkaline earth metal carbonates (MgCO₃, CaCO₃, SrCO₃, and BaCO₃) was studied under non-isothermal conditions using thermo-gravimetry. The activation energy and the pre-exponential factor for the decomposition reactions were determined using the Agarwal and Sivasubramanium integral approximation method. A new method was developed using a Turbo-C-based computer program to evaluate the integral of the kinetic equation. It was observed that the decomposition reaction of MgCO₃ and CaCO₃ followed two-dimensional diffusion-controlled kinetics and the decomposition reaction of SrCO₃ and BaCO₃ followed a Ginstling-Brounshtein model-based diffusion-controlled kinetics.