Effect of Template Agent on Catalytic Oxidation of NO by MgO/ZrO2

The MgO/ZrO2 catalyst was prepared using the solvothermal method for NO catalytic oxidation. The MgO/ZrO2 catalyst was modified by adding polyvinylpyrro-lidone (PVP) and polyethylene glycol-2000 (PEG-2000) template agents, and different template pairs were studied for the effect of NO on catalytic oxidation activity. The results indicate that incorporating PVP and PEG-2000 templates enhances the catalyst’s performance. The degree of NO oxidation over the MgO/ZrO2 catalyst rose as the temperature of the catalytic reaction increased; further, at 300°C when the templating agent was PVP, the catalytic activity of MgO/ZrO2 was the highest, and the oxidation degree of NO reached 78.8%. The catalysts were characterized by X-ray diffraction, scanning electron microscope, N2 adsorption/desorption, X-ray photoelectron spectroscopy, temperature programmed H2 reduction (H2-TPR), and Fourier transform infrared spectrometer. Deduced, the templating agent PVP can alter the crystal type of the MgO/ZrO2 catalyst and control the conversion of the m-ZrO2 crystal phase to t-ZrO2. In addition, the pore size of the MgO/ZrO2 catalyst can be tuned to form a mesoporous structure, the catalyst exhibited a notable rise in specific surface area and pore volume, and then the catalytic oxidation activity of NO was improved.