Journal ArticleDOI
Characterization of ceria-coated alumina carrier
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In this paper, it was shown that different types of cerium oxide species are formed on the surface depending on the amount of CeO2 and temperature of calcination of the samples.Abstract:
CeO2–Al2O3 mixed oxides with different CeO2 loading (in the range of 0.5–12 wt.%) were prepared by wetness impregnation of alumina with aqueous solution of di-ammonium hexanitrate cerate (NH4)2[Ce(NO3)6]. The samples after calcination at 773 and 1073 K were characterized by different techniques, using X-ray diffraction (XRD), UV–VIS diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and temperature-programmed reduction (TPR). It is shown that different types of cerium oxide species are formed on the surface depending on the amount of CeO2 and temperature of calcination of the samples. XRD showed the formation of nanocrystallites of ceria on alumina surface when the amount of CeO2 is higher than 6 wt.%; at lower concentrations ceria was found to be amorphous. The ceria loading lower than 6 wt.% stabilizes the textural properties of alumina. At loading of 1 wt.% of CeO2 XPS spectra reveals the presence of a strong interaction between ceria and alumina leading to a formation of superficial CeAlO3-like phase. TPR results show that well dispersed CeO2 particles present on the surface of alumina form CeAlO3 at temperature of reduction in the range of 873–993 K, while for the reduction of CeO2 crystallites, a higher temperature of reduction of 1190 K is needed.read more
Citations
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Journal ArticleDOI
Synthesis and Physicochemical Characterization of Nanostructured Pt/CeO2 Catalyst Used for Total Oxidation of Toluene
TL;DR: Nanostructured Pt/CeO2 with different loadings of platinum was successfully synthesized via redox reaction along with wet impregnation method in this paper, where the catalytic performance of the synthesized nanocatalysts was evaluated for abatement of toluene from waste gas stream.
Journal ArticleDOI
Investigation on properties of Pd/CeO2-ZrO2-Pr2O3 catalysts with different Ce/Zr molar ratios and its application for automotive emission control.
TL;DR: The results of XPS, in situ DRIFTS, etc., show that the number of oxygen vacancies increases with the increasing Zr content and thus leads to the enhanced metal-support interaction and the accelerative formation rate of nitrate, formate, acetate and carbonate species, resulting in improving catalytic performance for HC and NO elimination.
Journal ArticleDOI
Mechanistic Investigation of the Promotion Effect of Bi Modification on the NH3–SCR Performance of Ce/TiO2 Catalyst
TL;DR: In this paper, Bi was used as the modifier to elevate the performance of the Ce/TiO2 catalyst for selective catalytic reduction (SCR) of NOx with NH3.
Journal ArticleDOI
Synthesis and characterization of mesoporous ceria/alumina nanocomposite materials via mixing of the corresponding ceria and alumina gel precursors.
TL;DR: The presented method produces composite ceria/alumina materials that suit different applications in the field of catalysis and membranes technology, and throw some light on physicochemical factors that determine textural morphology and thermal stability of such important composite.
Journal ArticleDOI
Catalytic oxidative desulfurization technology of supported ceria based catalyst: Physicochemical and mechanistic studies
Wan Nazwanie Wan Abdullah,Wan Azelee Wan Abu Bakar,Rusmidah Ali,Wan Nur Aini Wan Mokhtar,Muhammad Nor Omar +4 more
TL;DR: In this paper, the catalytic activity of Mn/Ce/Al2O3 was higher than the monometallic catalysts, Ce/Al 2O3, and MnO2.
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Catalytic Properties of Ceria and CeO2-Containing Materials
TL;DR: A survey of the use of cerium oxide and CeO2-containing materials as oxidation and reduction catalysts is presented in this paper, with a special focus on catalytic interaction with small molecules such as hydrogen, carbon monoxide, oxygen, and nitric oxide.
Journal ArticleDOI
Ceria in automotive exhaust catalysts: I. Oxygen storage
H.C. Yao,Y.F. Yu Yao +1 more
TL;DR: In this article, the authors measured the oxygen removal at various temperatures using TPR traces of unsupported or alumina-supported ceria and showed that the reduction of surface capping oxygen and bulk oxygen anions is associated with reduction of the shared oxygen anion at the interface.
Book
X-Ray Diffraction in Crystals, Imperfect Crystals, and Amorphous Bodies
TL;DR: In the formalism of Newman-Penrose, a family of exact solutions of the Einsteirr-Maxwell equations of the type of Bertotti-Robinson is obtained with a cosmological term belonging to the degenerate type D in the algebraic classification of Petrov.