Journal ArticleDOI
Characterization of ceria-coated alumina carrier
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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Journal ArticleDOI
Hydrogen production from coke oven gas over LiNi/γ-Al2O3 catalyst modified by rare earth metal oxide in a membrane reactor
Zhibin Yang,Yunyan Zhang,Weizhong Ding,Yuwen Zhang,Peijun Shen,Yuding Zhou,Yong Liu,Shaoqing Huang,Xionggang Lu +8 more
Journal ArticleDOI
Promoting effect of ceria on the performance of NiPd/CeO2–Al2O3 catalysts for the selective hydrogenation of 1,3-butadiene in the presence of 1-butene
Franklin J. Méndez,Franklin J. Méndez,Laurent Piccolo,Roger Solano,Roger Solano,Mimoun Aouine,Yanet Villasana,Julia Guerra,Susana Curbelo,Claudio Olivera-Fuentes,Joaquín L Brito,Joaquín L Brito +11 more
TL;DR: In this article, the authors focused on the selective hydrogenation of 1,3-butadiene in the presence of 1-butene using (xCeO2-)Al2O3-supported NiPd catalysts (x = 0, 1, 2, and 3 wt% CeO2) in both liquid and gas conditions.
Journal ArticleDOI
Effects of the addition of small quantities of ceria on the catalytic behavior of Pd-only close-coupled catalysts during automobile exhaust elimination
TL;DR: In this article, a series of La-Al2O3 supported Pd-Ce close-coupled catalysts were synthesized by a co-adsorption impregnation method and subsequently investigated.
Journal ArticleDOI
Characterization and phase stability of pyrochlore (Nd1−xCex)2Zr2O7+y (x = 0–1)
Xin Wang,Kuo Jiang,Liang Zhou +2 more
TL;DR: The effects of cerium content on crystal structure, phase stability and microstructure of the (Nd1−xCex)2Zr2O7+y (x = 0-1) inert matrix materials were studied as discussed by the authors.
Journal ArticleDOI
Atomically dispersed rhodium on a support: the influence of a metal precursor and a support
TL;DR: The stability of rhodium is improved with the addition of promoters; the co-presence of samaria and ceria in the support and metal impregnation with a r Rhodium acetate precursor leads to the highest amount of atomically dispersed rhodia remaining after reductive treatment at 773 K.
References
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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.