Effect of Calcination Conditions on MnOx/Al2O3 Catalytic Efficiency for NO Oxidation

Calcination conditions in the catalyst preparation process have a significant influence on catalyst performance. To explore the optimal calcination condition of MnOx/Al2O3 catalysts for NO oxidation, a series of samples was prepared using the same support and active compound but under different calcination conditions. The catalytic efficiency of the catalyst was tested, and through characterization [X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE SEM), Brunauer-Emmett-Teller analysis (BET), and Barrett-Joyner-Halenda analysis (BJH)], the effect of calcination conditions on the catalytic performance was analyzed and discussed. The results showed that the samples calcined at 600 degrees C for 5 h had the best catalytic performance. At a reaction temperature of 450 degrees C, the molar ratio of NO2/NO conversion was as much as 1.65. The high surface area, crystal phase, and crystallinity (the relative content of Mn2O3 is about 50%); the high content of lattice oxygen O-beta (about 20.4%); and high dispersion of active sites on the MnOx/Al2O3 catalyst calcined at 600 degrees C for 5 h led to its relatively high catalytic activity. Compared with traditional noble metal catalysts, the MnOx/Al2O3 catalyst prepared by the impregnation method has good application prospects because of its low material cost, simple preparation process, and superior catalytic performance. (C) 2021 American Society of Civil Engineers.