Low temperature selective catalytic reduction of NO with NH ₃ over Mn supported on Ce _0.65Zr _0.35O ₂ prepared by supercritical method: Effect of Mn precursors on NO reduction

Catalysts for low-temperature selective catalytic reduction were developed using Ce _0.65Zr _0.35O ₂ (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 N ₂ 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.