Low temperature selective catalytic reduction of NO with NH3 over Mn supported on Ce_(0.65)Zr_(0.35)O2 prepared by supercritical method: Effect of Mn precursors on NO reduction

摘要

Catalysts for low-temperature selective catalytic reduction were developed using Ce_(0.65)Zr_(0.35)O2 (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.