Journal ArticleDOI
Characterization of ceria-coated alumina carrier
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TLDR
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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The promotion effect of Cr additive on CeZr2Ox catalyst for the low-temperature selective catalytic reduction of NOx with NH3
TL;DR: In this paper, a sequence of Cr-modified CeZr2Ox catalysts were synthesized through the co-precipitation way and applied in selective catalytic reduction (SCR) of NOx with ammonia.
Journal ArticleDOI
Non-template hydrothermal route derived mesoporous Ce0.2Zr0.8O2 nanosized powders with blue-shifted UV absorption and high CO conversion activity
TL;DR: In this paper, the mesostructured Ce0.2Zr0.8O2 powders were synthesized via a hydrothermal method in the presence of urea without any templates using a trivalent cerium salt as the starting material.
Journal ArticleDOI
Oxidation of benzene over bimetallic Cu–Ce incorporated rice husk silica catalysts
Farook Adam,Radhika Thankappan +1 more
TL;DR: In this paper, a series of rice husk silica catalysts using acetonitrile as solvent at 343 K under atmospheric pressure were used for benzene to phenol with 30% H 2 O 2 in liquid-phase.
Journal ArticleDOI
Preparation and Characterization of Me2O3−CeO2 (Me = B, Al, Ga, In) Mixed Oxide Catalysts. 2. Preparation by Sol−Gel Method
TL;DR: In this paper, a combination of ceria mixed with another oxide from group III, using the sol-gel method, has been investigated, and the structural, textural, and surface properties of these catalysts have been fully characterized by means of a variety of techniques (Brunauer−Emmett−Teller, BET; X-ray diffraction analysis, XRD; Raman; scanning electron microscopy, SEM; thermogravimetric analysis, TG; and temperature-programmed reduction/oxidation, TPR-TPO).
Journal ArticleDOI
Low-temperature combustion of chlorinated hydrocarbons over CeO2/H-ZSM5 catalysts
Beatriz de Rivas,Carmen Sampedro,Rubén López-Fonseca,Miguel A. Gutiérrez-Ortiz,José I. Gutiérrez-Ortiz +4 more
TL;DR: The performance of various CeO 2 /H-ZSM5 catalysts was evaluated for the oxidation of one of the most common chlorinated pollutants found in waste streams, namely 1,2-dichloroethane as discussed by the authors.
References
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High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold
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Journal ArticleDOI
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.