Non-isothermal decomposition kinetics of bayeritic bauxite

Kinetics of thermal decomposition of bauxite sample has been studied by thermogravimetric analysis (TG-DTGA) in static air under non-isothermal condition. Integral approximation method of Coats and Redfern was used to determine the kinetic parameters like order of reaction and activation energy for the dehydration process. Different kinetic functions were also derived with the experimental data applying Jerez method to ascertain the decomposition mechanism of bauxite. It has been observed that the dehydration reaction followed first order reaction kinetics with contracting volume kinetic mechanism where mass transfer by diffusion between parent bauxite and dehydrated pseudo boehmite phases determines the rate of dehydration.