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A MnCeInO x catalyst was prepared by a coprecipitation method for denitrification of NH3-SCR (selective catalytic reduction). The catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption. The NH3-SCR activity and H2O and SO2 resistance of the catalysts were evaluated. The test results showed that the SCR and water resistance and sulfur resistance were good in the range of 125–225 °C. The calcination temperature of the Mn6Ce0.3In0.7O x catalyst preparation was studied. The crystallization of the Mn6Ce0.3In0.7O x catalyst was poor when calcined at 300 °C; however, the crystallization is excessive at a 500 °C calcination temperature. The influence of space velocity on the performance of the catalyst is great at 100–225 °C. FTIR test results showed that indium distribution on the surface of the catalyst reduced the content of sulfate on the surface, protected the acidic site of MnCe, and improved the sulfur resistance of the catalyst. The excellent performance of the Mn6Ce0.3In0.7O x catalyst may be due to its high content of Mn4+, surface adsorbed oxygen species, high specific surface area, redox sites and acid sites on the surface, high turnover frequency, and low apparent activation energy.

MnxZr1 series catalysts were prepared by a coprecipitation method.

Fe‐doped CoCr oxide catalysts are prepared by solid‐phase mixing method, coprecipitation method, mechanical mixing method, and citric acid method, respectively, and their catalytic activity in the selective catalytic reduction of nitrogen oxides with NH3 (NH3‐SCR) is tested. The Fe0.5CoCrOx catalysts prepared by all preparation methods have good water resistance and sulfur resistance when the calcination temperature is 400 °C. Fe0.5CoCrOx prepared by coprecipitation method by calcination at 400 °C (CP‐400) is shown to have the optimum catalyst activity. In addition, the catalysts are characterized by a series of characterizations. The characterization results show that CP‐400 has the largest specific surface area, which makes the active and acidic sites highly dispersed on the surface of CP‐400, resulting in stronger redox and acidity and improved SCR activity. The removal of NO by NH3‐SCR over CP‐400 at 150 °C follows the Eley‐Rideal (ER) and Langmuir‐Hinshelwood (LH) mechanisms.