In situ IR studies of selective catalytic reduction of NO with NH3 on Ce-Ti amorphous oxides

Li, Qian; Gu, Huachun; Li, Ping; Zhou, Yuhao; Liu, Ying; Qi, Zhong‐Nan; Xin, Ying; Zhang, Zhaoliang

doi:10.1016/s1872-2067(14)60154-6

Cited by 66 publications

(39 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The band at ~1417 cm -1 nearly disappeared at o C, whereas the band at 1238 cm -1 is still clearly observed. An additional band at ~1361 cm -1 was observed which could be ascribed to an oxidised product of adsorbed ammonia [38,43,44]. These results provide persuasive evidence that the atomic-scale interaction in the short-range ordered W-O-Fe structure enhances both Lewis and Brønsted acidity of the catalysts and these are favorable for catalytic activity.…”

mentioning

confidence: 67%

“…As for Brønsted acidity, a greater intensity peak ~1440 cm -1 was observed for W0.13FeOx than Fe2O3. The increase in amounts of both the Lewis and Brønsted acidity promotes catalytic activity [37][38][39][40][41][42]. With increasing temperature, both the peak intensities due to adsorption at Lewis and Brønsted acid sites decreased, with the later exhibiting lower thermal stability compared with ammonia on Lewis acid sites.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Selective catalytic reduction of NO with NH3 over short-range ordered W O Fe structures with high thermal stability

Xin

Zhang

et al. 2018

Applied Catalysis B: Environmental

Self Cite

View full text Add to dashboard Cite

The selective catalytic reduction (SCR) of NOx with NH3 was studied over poorlycrystalline W-Fe composite oxides (WaFeOx). The short-range order present within the W-O-Fe structure was found to be responsible for the excellent SCR activity, in which the strong atomic-level interaction between Fe and W atoms promoted the formation of both Lewis and Brønsted acidity. The W-O-Fe structure existed as amorphous overlayers, approximately 2 nm thick over the surface of crystalline particles after high-temperature aging as shown by highangle annular dark field scanning transmission electron microscopy (HAADF-STEM). After treatment at 800 o C for 5 h, the WaFeOx catalysts still showed almost 100% NO conversion in the range 300-450 o C with 100% N2 selectivity, despite the loss in surface area. This resistance to the impacts of high temperature ageing guarantees high activity of SCR catalysts which often suffer during high-temperature excursions as in the case of diesel exhaust due to diesel particulate filter (DPF) regeneration.

show abstract

mentioning

confidence: 67%

mentioning

confidence: 99%

Selective catalytic reduction of NO with NH3 over short-range ordered W O Fe structures with high thermal stability

Xin

Zhang

et al. 2018

Applied Catalysis B: Environmental

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, Ti sites might be the acidic sites in Ce-Ti-400. Li [10] drew the same conclusion that TiO2 plays the role in providing surface Lewis acid sites. One may argue that weak NH3 desorption peak on Ce-Ti-400 was similar to that of CeO2.…”

Section: No-tpd and Nh 3 -Tpdmentioning

confidence: 90%

“…In addition, the Ce-O-Ti structure with the interaction between Ce and Ti was confirmed to be the main active site. Li et al [10] later reported…”

Section: Introductionmentioning

confidence: 97%

Active Site of O2 and Its Improvement Mechanism over Ce-Ti Catalyst for NH3-SCR Reaction

et al. 2018

View full text Add to dashboard Cite

Abstract:The current study on Ce-Ti catalyst was mainly focused on the function of NH 3 and NO adsorption sites. In our study, by comparing Ce-Ti (doped catalyst) to Ce/Ti (supported catalyst), the active site of O 2 and its improvement mechanism over Ce-Ti catalyst for NH 3 -Selective catalytic reduction (SCR) reactions were investigated. For Ce-Ti catalyst, a cerium atom was confirmed entering a TiO 2 crystal lattice by X-ray diffraction (XRD) and Raman; the structure of Ce--Ti ( represents oxygen vacancy) in Ce-Ti catalyst was confirmed by X-ray photoelectron spectroscopy (XPS) and Photoluminescence spectra (PL spectra). The nature of this structure was characterized by electron paramagnetic resonance (EPR), Ammonia temperature-programmed desorption (NH 3 -TPD), hydrogen temperature-programmed reduction (H 2 -TPR), Nitric oxide temperature-programmed desorption (NO-TPD) and In situ DRIFT. The results indicated that oxygen vacancies had a promotive effect on the adsorption and activation of oxygen, and oxygen was converted to superoxide ions in large quantities. Also, because of adsorption and activation of NO and NH 3 , electrons were transferred to adsorbed oxygen via oxygen vacancies, which also promoted the formation of superoxide ions. We expected that our study could promote understanding of the active site of O 2 and its improvement mechanism for doped catalyst.

show abstract

“…There is no peak at 27.5° in the samples, which indicates that there is no rutile titania existing in all samples [17,18]. Moreover, no obvious characteristic peak assigned to a particular phase oxide is observed in 2% and 3% samples, which indicates that the amorphous phase was formed and become dominant phase in the samples [19]. This means that appropriate transition metal Cd facilitates the formation of amorphous mixed oxides.…”

Section: Catalytic Activity Measurementmentioning

confidence: 94%

The Selective Catalytic Reduction of NOx Over Cd-Ce-Ti Metal Oxide Catalysts

Duan¹,

Liu²,

Shi³

et al. 2017

J Environ Anal Toxicol

View full text Add to dashboard Cite

In situ IR studies of selective catalytic reduction of NO with NH3 on Ce-Ti amorphous oxides

Cited by 66 publications

References 36 publications

Selective catalytic reduction of NO with NH3 over short-range ordered W O Fe structures with high thermal stability

Selective catalytic reduction of NO with NH3 over short-range ordered W O Fe structures with high thermal stability

Active Site of O2 and Its Improvement Mechanism over Ce-Ti Catalyst for NH3-SCR Reaction

The Selective Catalytic Reduction of NOx Over Cd-Ce-Ti Metal Oxide Catalysts

Contact Info

Product

Resources

About