Understanding the temperature-dependent H2O promotion effect on SO2 resistance of MnO -CeO2 catalyst for SCR denitration

Mechanistic Insight into the Promotion of the Low-Temperature NH3–SCR Activity over NiMnFeOx LDO Catalysts: A Combined Experimental and DFT Study

“…After 30 min of 2000 ppm NO and 5% O 2 /Ar adsorption (Figure S7g,h), several IR bands appeared, which were assigned to NO 2 molecules (1610–1618 cm –1 ), bidentate nitrate (1572–1592 cm –1 ), and bridging nitrate (1235–1286 cm –1 ). , The intensity of the IR signals on the Ni 0.5 Mn 0.5 Fe 0.5 O x surface was significantly higher than that on the Mn/γ-Al 2 O 3 surface. These in situ DRIFTS results further demonstrate that there are more active sites on the surface of the Ni 0.5 Mn 0.5 Fe 0.5 O x catalyst for the adsorption and activation reactive species.…”

A Comparative Study on the Effect of Surface and Bulk Sulfates on the High-Temperature Selective Catalytic Reduction of NO with NH3 over CeO2

“…2− [30]. In addition, a smaller surface atomic concentration of S is observed for B-CeS (2.13%) when compared to S-CeS (3.60%).…”

“…In general, both catalysts show poor activity in converting NO to NO 2 , which is evidenced by the high temperature required to initiate the reaction (250 • C and the obtained poor maximum conversion efficiency (<20%). It has been previously reported that although ceria has excellent redox properties, it shows poor NO oxidation performance and, due to the strong electron-withdrawing effect from S=O in sulfate group, the modification of sulfate species can induce a further deterioration in NO oxidation performance [30]. From this point of view, it is reasonable that the B-CeS displayed a better NO oxidation performance than the S-CeS, since the main body of ceria is less disrupted by bulk sulfates in B-CeS.…”

Recent Progress on Density Functional Theory Calculations for Catalytic Control of Air Pollution

“…Ji et al combined experimental and theoretical calculations to confirm that the presence of H 2 O facilitated the formation of −OH on the defective sites. 89 The formation of more sulfites retarded the destructive effect of strong electron-absorbing sulfates on the active Mn sites and ensured the sustained stability of the catalyst. Liu et al conducted a comprehensive study to reveal the mechanisms of S doping on Fe 2 O 3 /TiO 2 catalysts in the SCR reaction.…”

“…The catalyst deactivation caused by Se 0 and SeO 2 is through the destruction of the active sites by pronounced electron transfer processes. Ji et al combined experimental and theoretical calculations to confirm that the presence of H 2 O facilitated the formation of −OH on the defective sites . The formation of more sulfites retarded the destructive effect of strong electron-absorbing sulfates on the active Mn sites and ensured the sustained stability of the catalyst.…”