The Role of Medium Acid Sites Tuned by Ce Adding in Moderate-Temperature NH3-SCR

Bie, Xuan; Jiao, Kunling; Gong, Chunqin; Qu, Baozhong; Liu, Daokuan; Ma, Shuangchen

doi:10.1007/s10562-021-03797-0

Cited by 3 publications

(1 citation statement)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the literature, the spectra can be recognized as having eight peaks, and the ones marked u' and v' are related to Ce 3+ species; the others, which are labeled u, v, u", v", u"' and v"', are ascribed to Ce 4+ species [40][41][42][43]. As generalized in Table 3, the Ce 3+ /(Ce 3+ + Ce 4+ ) ratios increase from 44.4% to 54.4% over the surface with an increase in the Ce contents, which is due to the formation of Cu 2+ in the redox cycles Cu + + Ce 4+ → Cu 2+ + Ce 3+ [37,44]. Consequently, the addition of Ce leads to the electron transfer of Cu + , forming more Cu 2+ and contributing to the high NH 3 -SCR activity.…”

Section: Cu and Ce Speciesmentioning

confidence: 91%

Positive Effect of Ce Modification on Low-Temperature NH3-SCR Performance and Hydrothermal Stability over Cu-SSZ-16 Catalysts

Liang

et al. 2023

Catalysts

View full text Add to dashboard Cite

Cu-exchanged SSZ-16 zeolite catalysts exhibit outstanding NH3-SCR activity, but their catalytic performance after hydrothermal treatments is not ideal. In order to improve the hydrothermal stability of Cu-SSZ-16, CuCex-SSZ-16 series catalysts were prepared via an ion exchange process, and the effect of Ce modification on the hydrothermal stability was investigated. In addition, increasing Ce contents significantly improved the hydrothermal stability, and CuCe0.87-SSZ-16 showed the best hydrothermal stability. The effects of adding Ce to active species and the AFX framework were studied by various characterization measurements. The 27Al MAS NMR results reveal that Ce modification can strengthen the structural stability of the CuCex-SSZ-16 catalysts. Furthermore, the combined results of XPS, H2-TPR, and in situ DRIFTS confirm that the introduction of Ce markedly increases the active Cu2+-2Z species, contributing to the remarkable hydrothermal stability.

show abstract

Section: Cu and Ce Speciesmentioning

confidence: 91%

Positive Effect of Ce Modification on Low-Temperature NH3-SCR Performance and Hydrothermal Stability over Cu-SSZ-16 Catalysts

Liang

et al. 2023

Catalysts

View full text Add to dashboard Cite

show abstract

Functional distinction of different components in SmCeMn/Ti catalytic system for NH3-SCR

Líu

Qin

et al. 2023

Applied Surface Science

View full text Add to dashboard Cite

Synergistic effect of Ce doping and phosphorylation on optimizing the low temperature NH 3 -SCR activity of the spent V 2 O 5 -WO 3 /TiO 2 catalyst

Wang,

Qi,

Wang

et al. 2024

Preprint

View full text Add to dashboard Cite

The reactivation and subsequent reuse of the exhausted SCR catalyst holds significant economic and environmental advantages. Water and acid washing along with thermal regeneration were commonly utilized to eliminate toxic substances from the catalyst surface, while these processes often resulted in the undesired loss of active components. In this research, an impregnation approach was adopted to replenish the depleted active constituents of the spent V2O5-WO3/TiO2 catalyst (denoted as VW/Ti). Experimental investigations were conducted to evaluate the influence of Ce/P doping on both the Selective Catalytic Reduction (SCR) activity of this rejuvenated catalyst and its resistance to the detrimental effects of SO2/H2O exposure. The optimal performance is achieved with the Ce/P co-doped VW/Ti catalyst, demonstrating a remarkable efficiency in removing nearly 100% of NOx across a broad temperature ranging from 150°C to 450°C. The incorporation of a proper content of Ce serves to elevate the VOx surface density from a sub-monolayer state to a monolayer and foster the formation of more surface oxygen vacancy. This transformation positively contributes to enhancing both the catalytic activity and the resistance to the SO2/H2O poisoning. Further treatment with H3PO4, although rendering the catalyst more susceptible to H2O, achieves a delicate balance between its surface acidity and redox capabilities. This optimized state not only enhances the catalyst's robustness but also further widens the active temperature window.

show abstract

The Role of Medium Acid Sites Tuned by Ce Adding in Moderate-Temperature NH3-SCR

Cited by 3 publications

References 43 publications

Positive Effect of Ce Modification on Low-Temperature NH3-SCR Performance and Hydrothermal Stability over Cu-SSZ-16 Catalysts

Positive Effect of Ce Modification on Low-Temperature NH3-SCR Performance and Hydrothermal Stability over Cu-SSZ-16 Catalysts

Functional distinction of different components in SmCeMn/Ti catalytic system for NH3-SCR

Synergistic effect of Ce doping and phosphorylation on optimizing the low temperature NH 3 -SCR activity of the spent V 2 O 5 -WO 3 /TiO 2 catalyst

Contact Info

Product

Resources

About