Thermogravimetric analysis of the catalytic effect of metallic compounds on the combustion behaviors of coals

摘要

Effects of KNO3, CeO2, Fe2O3, their mixture and their thermally treated mixture on the combustion reactivity of two coals, bituminous coal (BC) and high ash coal (HAC), were investigated by thermogravimetric analysis. The ignition performance, burnout performance and exothermic behavior were used to evaluate the catalytic effect. Moreover, the kinetic parameters were determined using the Coats-Redfern method. The results indicated that the activity sequence of the catalysts on BC relative to the ignition performance can be described as follows: the thermally treated mixture > the mixture > KNO3 > Fe2O3 > CeO2> and the activity sequence relative to the burnout performance is the same. The activity sequence of the catalysts on HAC relative to the ignition performance can be described as follows: the thermally treated mixture > the mixture > Fe2O3 > CeO2 > KNO3, and the activity sequence relative to the burnout performance is the same. The exothermic heats of catalyst-incorporating samples increased and the activation energies of the samples decreased.