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Graphical abstract Highlights • The combustion activity improved significantly by adding Fe 2 O 3 and CeO 2. • Reduction of NO by CO was enhanced effectively by adding Fe 2 O 3 and CeO 2. • The combined process of catalytic combustion and catalytic denitration is proposed. • Synergistic catalytic effect of ferric oxide and cerium oxide is proposed. Abstract The processes of catalytic combustion and catalytic denitration of semi-coke were conducted in the presence of catalysts Fe 2 O 3 and CeO 2, The comprehensive performance of these processes was evaluated with thermogravimetry analysis and infrared spectroscopy. The results indicate that the combustion activity improved significantly when we added Fe 2 O 3 and CeO 2 separately. Furthermore, the mixture of Fe 2 O 3 and CeO 2 has better combustion efficienty. When Fe 2 O 3 and CeO 2 were added separately, there was a decline in NO and CO emission (NO: 10.11% vs. 6.48%, CO: 7.18% vs. 5.28%). Meanwhile, the mixture of Fe 2 O 3 and CeO 2 caused a great decline in the total amounts of NO and CO emission (NO: 20.70%, CO: 16.33%). The denitration effect is ascribed to the homogeneous reduction of NO by CO, enhanced by adding the catalysts CeO 2 and Fe 2 O 3. Fe 2 O 3 and CeO 2 are catalytically active in promoting not only coke combustion but also NO reduction. Fe 2 O 3 and CeO 2 are associated, synergically catalyzing the semi-coke combustion. [ABSTRACT FROM AUTHOR]

Graphical abstract Synergistic catalytic denitration process over the Fe 2 O 3 and CeO 2 mixture. Highlights • Iron and rare earth minerals enhanced the reduction of NO by CO. • Fe 2 O 3 and CeO 2 synergistically catalyzed the reduction of NO by CO. • CeO 2 promote the redox cycle of the Fe 2 O 3 catalyst. Abstract The catalytic activities of iron concentrate, rare earth concentrate, and rare earth tailings for semi-coke denitration were studied using thermogravimetric analysis combined with Fourier transform infrared spectroscopy. The results revealed that less NO was produced from semi-coke combustion with the addition of iron and rare earth minerals, and meanwhile CO production was reduced as well. It is likely that the addition of iron and rare earth minerals enhances the homogeneous reduction of NO by CO thus improving the removal efficiency of nitrogen oxides. The catalytic activity of rare earth tailings was higher than those of rare earth concentrate and iron concentrate. It is evidenced that ferric oxide and rare earth oxides in the tailings are associated, synergically catalyzing the homogeneous reduction of NO by CO. [ABSTRACT FROM AUTHOR]