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Abstract: Catalytic oxidation of benzene with ozone has been studied using manganese oxides with two different manganese precursors, Mn(NO3)2 and Mn(CH3COO)2, supported on SBA-15 (MnO x /SBA-15). The catalysts were characterized by X-ray diffraction, N2 adsorption–desorption, Raman spectroscopy, and H2-temperature programmed reduction. The manganese nitrate (MN) precursor primarily resulted in large particles on the silica support, while the manganese acetate (MA) precursor mainly resulted in a highly dispersed manganese oxide on the silica support. The catalytic activity was dependent upon ozone concentration, reaction times, and the amount of Mn loading. Higher benzene conversion, O3 conversion, and CO x yield were observed for MnO x -MA/SBA-15 catalyst over MnO x -MN/SBA-15, due to the highly dispersed manganese oxides on the supports, and the higher oxygen mobility. The 15wt% MnO x -MA/SBA-15 catalyst shows the highest catalytic activity of all the catalysts considered in this study. [Copyright &y& Elsevier]

Abstract: Catalysts for low-temperature selective catalytic reduction were developed using Ce0.65Zr0.35O2 (CZO) generated via hydrothermal synthesis in supercritical water as the support. To evaluate the manganese precursors, which are known to have good de-NOx performance at low temperature, manganese acetate (MA) and manganese nitrate (MN) were impregnated on the CZO support. The developed catalysts were characterized using N2 adsorption–desorption, TGA, XRD, XPS and TPR. De-NOx experiments were carried out using a NOx analyzer to evaluate the performance of the developed catalysts. The MA-impregnated catalyst exhibited higher de-NOx efficiency than that impregnated with MN. This result was attributed to the difference in crystal phase and concentration of surface Mn and the resulting difference in the reducing ability. [Copyright &y& Elsevier]