Reactivity of pulverized coals during combustion catalyzed by CeO2 and Fe2O3

Effects of CeO2 and Fe2O3 on combustion reactivity of several fuels, including three ranks of coals, graphite and anthracite chars, were investigated using thermo-gravimetric analyzer. The results indicated that the combustion reactivity of all the samples except lignite was improved with CeO2 or Fe2O3 addition. It was interesting to note that the ignition temperatures of anthracite were decreased by 50 degrees C and 53 degrees C, respectively, with CeO2 and Fe2O3 addition and that its combustion rates were increased to 15.4%/min and 12.2%/min. Ignition temperatures of lignite with CeO2 and Fe2O3 addition were 250 degrees C and 226 degrees C, and the combustion rates were 12.8% and 19.3%/min, respectively. When compared with those of lignite without catalysts, no obvious catalytic effects of the two catalysts on its combustion reactivity were revealed. The results from the combustion of the three rank pulverized coals catalyzed by CeO2 and Fe2O3 indicated significant effects of the two catalysts on fixed carbon combustion. And it was found that the higher the fuel rank, the better the catalytic effect. The results of combustion from two kinds of anthracite chars showed obvious effects of anthracite pyrolysis catalyzed by CeO2 and Fe2O3 on its combustion reactivity. (C) 2009 The Combustion Institute. Published by Elsevier Inc. All rights reserved.