Low-temperature selective catalytic reduction of NO with NH3 over MnCe oxides supported on TiO2 and Al2O3: A comparative study

Effect of Ce/Y Addition on Low-Temperature SCR Activity and SO2 and H2O Resistance of MnOx/ZrO2/MWCNTs Catalysts

“…Compared to the fresh catalysts, the Mn 2p 1/2 and 2p 3/2 peaks of the used MnZr catalysts (Figure 6a) moved from 653.4 eV and 642.2 eV to 654.1 eV and 642.7 eV, respectively. This was due to the sulfation of the manganese, which made the Mn 2p 3/2 peak of the Mn/TiO 2 catalysts shift towards a higher binding energy (approximately 0.7 eV after SCR with SO 2 ), in accordance with the study of Jin [37]. When loading Ce or Y, the peaks were not significantly varied.…”

Manganese–niobium mixed oxide catalyst for the selective catalytic reduction of NOx with NH3 at low temperatures

“…8 The NbO x catalyst showed the largest broad desorption peak, indicating a large amount of acid sites. It is generally accepted that NH 4 + ions bound to Bronsted acid sites are less thermally stable than coordinated NH 3 molecules bound to Lewis acid sites and desorb at lower temperatures [25,26]. Only a small amount of desorbed NH 3 was detected over MnO x catalyst.…”

Nb-doped VOx/CeO2 catalyst for NH3-SCR of NOx at low temperatures

“…It is generally accepted that NH 4 + ions bound to Brønsted acid sites are less thermally stable than coordinated NH 3 molecules bound to Lewis acid sites and desorb at lower temperatures. 18,23,24 Therefore, the desorption peak at 100 C could be ascribed to the desorption of physisorbed NH 3 and the partial ionic NH 4 + bound to the weak Brønsted acid sites, and the peak at 250 C could be assigned to the desorption of ionic NH 4 + bound to strong ). [28][29][30] On the Nb-VO x /CeO 2 catalyst, the adsorption amount of NO x was larger than that on the VO x /CeO 2 catalyst (1.67 : 1).…”