| 초록 |
MnOx supported on Al2O3, TiO2, ZrO2 and SiO2 were prepared by a precipitation method and a wet impregnation method, and their catalytic activity for the low-temperature selective catalytic reduction (SCR) of NOx with NH3 in the presence of excess O2 was examined. The activity of the catalysts prepared by a precipitation method was higher than that of catalysts prepared by an impregnation method. The activity follows in the order: MnOx/TiO2 ≈ MnOx/Al2O3 ＞ MnOx/SiO2 ＞ MnOx/ZrO2. Supported MnOx catalysts prepared by a precipitation method showed an amorphous manganese oxide phase and those prepared by an impregnation method exhibited a crystalline MnO2 phase, respectively. This high de-NOx activity of MnOx supported catalyst prepared by a precipitation method at low temperature is probably due to their amorphous framework structure and the existence of residual carbon oxide species. |
