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Fuentes, S.; Bogdanchikova, Nina; Díaz, Gabriela; Peraaza, M.; Sandoval, G.

doi:10.1023/a:1019055626748

Cited by 27 publications

(6 citation statements)

References 16 publications

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“…In the second domain, a third large peak appeared at 420°C. This peak was ascribed to hydrogen much more bonded to the catalyst surface [23][24][25]. Similar H 2 -TPD profiles were reported for Ni catalysts deposited on other support.…”

Section: Chemisorption Studiessupporting

confidence: 82%

Synthesis of Ni/SiO2 nanoparticles for catalytic benzene hydrogenation

Chettibi

Boudjahem

Bettahar

2010

Transition Met Chem

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Nickel nanoparticles supported on silica were prepared by hydrazine reduction in aqueous medium. The obtained solids were characterized by X-ray diffraction (XRD), Transmission Electronic Microscopy (TEM), Electron Diffraction (ED), hydrogen chemisorption, and Temperature Programmed Desorption of hydrogen (H 2 -TPD). The catalytic properties were evaluated for benzene hydrogenation in the temperature range 75-230°C. XRD patterns reveal presence of the metallic nickel particles with fcc structure. Metal dispersion and hydrogen storage increase with decreasing metal particle size. The H 2 -TPD profiles exhibit two domains, one due to desorption of hydrogen from Ni metal and another due to spillover from metal to the support. The catalytic activity strongly depends on the metal loading. It increases with decreasing metal loading. This is attributed to metal surface area, which also increases with decreasing metal loading. Kinetic studies of benzene hydrogenation on the Ni catalysts showed that the benzene partial order is around -2. This significant negative value is ascribed to a strong adsorption of benzene on the catalyst surface.

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Section: Chemisorption Studiessupporting

confidence: 82%

Synthesis of Ni/SiO2 nanoparticles for catalytic benzene hydrogenation

Chettibi

Boudjahem

Bettahar

2010

Transition Met Chem

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“…% a reduction peak appeared, around 740 K, the H 2 -comsuption is higher compared to the amount of PdO (Table 1), resulting in the H 2 consumption/PdO ratio higher than the stoichiometric. There are some controversies about how to assign the H 2 consumption at 740 K [10,[12][13][14][15][16] but several authors suggest that this peak may be related to the reduction of small quantities of La 2 O 3 to LaO x [10]. However, TPR experiments done with (x)La-Al 2 O 3 supports (not showed) reveal that there is no H 2 consumption up to 1,273 K. Therefore, it could be suggested that this peak is due to the reduction of the lanthana support that supposedly is associate with the cleavage of the H-H bond on highly dispersed Pd 0 particles, which promote the reduction of the lanthana.…”

Section: Resultsmentioning

confidence: 99%

Effect of CeO2 and La2O3 on the Activity of CeO2−La2O3/Al2O3-Supported Pd Catalysts for Steam Reforming of Methane

et al. 2007

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The effect of the addition of CeO 2 or La 2 O 3 on the surface properties and catalytic behaviors of Al 2 O 3 -supported Pd catalysts was studied in the steam reforming of methane. The FTIR spectroscopy of adsorbed CO and the Pd dispersion suggest the partial coverage of Pd 0 by ceria or lanthana species. This could lead to the formation of an adduct MPd x O (M = Ce or La) at the surface of the metal crystallites. The addition of ceria or lanthana resulted in an increase of the turnover rate and specific rate for steam reforming of methane. One possible explanation if that the Pd 0 *Pd d+ O-M interfacial species (M = Ce or La) are oxidized by H 2 O or CO 2 , promoting the O* transfer to the metal surface. This could facilitate the removal of C* species from the metal surface, resulting in the increase of specific reaction rate and increase of the accessibility of CH 4 to metal active sites.

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“…Supports based on nanocrystalline pure alumina, alumina doped by ceria (30%) and alumina doped by CeZrO 2 (30%) have been prepared by the sol-gel technique using organic precursors as in [3]. Gold (3 wt%) catalysts were prepared by the deposition-precipitation technique using urea and HAuCl 4 as a gold precursor according to [4].…”

Section: Methodsmentioning

confidence: 99%