Ge, Mn-doped CeO2–WO3 catalysts for NH3–SCR of NOx: Effects of SO2 and H2 regeneration

The use of ceria for the selective catalytic reduction of NOx with NH3

“…The catalyst exhibited high activity, high N2 selectivity, and good SO2 durability in a broad temperature range of 175-500 C at a space velocity of 47 000 h −1 . Ge and Mn were used by Chang et al [43] for further improving the CeO2-WO3 catalyst. Liu et al [44] compared CeO2-WO3 catalysts prepared by various methods and concluded that the high NH3-SCR activity could be attributed to large surface area, high surface concentrations of Ce and Ce 3+ , enhanced NO oxidization ability, and high concentration of surface acid sites.…”

SnO –MnO –TiO2 catalysts with high resistance to chlorine poisoning for low-temperature chlorobenzene oxidation

“…Manganese oxides, as a type of environmentally friendly material, have attracted continuous attention because of their excellent catalytic performance and widespread applications, such as the catalytic combustion of toluene, benzene and ethyl acetate [4][5][6][7][8]; the selective catalytic reduction of NO x with NH 3 [9][10][11][12][13]; and CO oxidation or hydrogenation [14][15][16]. Therefore, manganese oxides have been widely recognized as one of the most efficient transition-metal oxide catalysts for catalytic disposal of pollutants and have great potential as an alternative to VO x in the abatement of CVOCs [17][18].…”

Low Temperature Performance of Selective Catalytic Reduction of NO with NH3 under a Concentrated CO2 Atmosphere

“…SO2 is known to have a negative effect on NO conversion due to catalyst poisoning [6,11,30]. As shown in Figure 8, for all of the tested three catalysts (Mn/AC, Ce/AC and Mn-Ce/AC), the CO2 From Figure 7, it seems that for the Mn/AC catalyst, higher NO conversion was observed under the CO 2 atmosphere compared with the N 2 atmosphere, under high space velocity (13,632 h´1).…”

“…Furthermore, it is known that SCR performance is significantly affected by the process conditions such as temperature, space velocity [26][27][28], concentrations of H 2 O [25,[29][30][31], and the presence of SO 2 [6,11,25,30,32,33]. For example, Magnusson et al [25] investigated SCR using a marine based catalyst; they reported that higher space velocity (18,300 h´1) resulted in a continuous decrease in catalytic activity, compared with space velocities of 6100 and 12,200 h´1; in addition, they also reported that at temperatures higher than 300˝C, the catalyst showed a stable catalytic reactivity at different SO 2 concentrations, but a significant reduction of SCR activity was observed at a temperature of 250˝C for gas streams containing 250 and 750 ppm SO 2 .…”

“…Among them, Mn-and Ce-based catalysts have drawn particular attention due to their abundant oxygen vacancies, which promote the redox cycle during SCR reactions [11][12][13][14]. In addition, activated carbon (AC) has been used as catalyst support for SCR, since it has high surface for metal loading and the presence of functional groups on the surface of activated carbon can also promote NO x conversion [15][16][17][18][19].…”