Thermogravimetric Analysis of Desulfurization Characteristics and Kinetic Parameters of Limestone Modified by Red Mud

Abstract

The effects of three kinds of red mud from alumina plant on limestone’s sulfation kinetics were investigated by thermogravimetric analysis method. Red mud can effectively improve the desulfurization performance of limestone in the whole temperature range. Red mud has little effect on the rate constant of the surface reaction (k), but it can significantly improve the effective diffusivity of reactant in the product layer (Ds). The enhancement of sulfation is more pronounced once the product layer has been formed and consequently the promoting effect becomes greater once the sulfation reaction becomes diffusion controlled.