Catalytic combustion of coke and NO reduction in-situ under the action of Fe, Fe-CaO and Fe-CeO2

Abstract Efficient and inexpensive catalysts are crucial to the industrial application of catalytic combustion of coal or coke. The effect of Fe and Fe-CaO on the coke combustion and the in-situ reduction of NO emission were investigated in this work. In addition, Fe-CeO2 was used for comparison due to its excellent performance reported in the literature. It is found that 1-2 %Fe addition effectively catalyzed coke combustion, and the combustion index and burnout index increased by a factor of 1.2 and 1.4, respectively. CaO significantly improved the catalytic performance of Fe on coke combustion. By adding 4-10% CaO and 2% Fe simultaneously, the combustion index and burnout index of coke were increased by 1.4 and 1.9 times, respectively. By contrast, CeO2 had little effect on Fe-catalyzed coke combustion. The NO emission was reduced by 16.7% by adding 2% Fe during coke combustion. The NO abatement increased to 38.4% and 39.6%, respectively, when adding 10% CaO and 4% CeO2 to coke combustion with 2% Fe. It was concluded that Fe could promote the decomposition of NO, as well as the reactions of C-NO and NO-CO, simultaneously.