Conversion of guaiacol over different Re active phases supported on CeO^sub 2^-Al^sub 2^O^sub 3

The effect of Al2O3 modification by CeO2 addition (14 wt.% to obtain a maximum monolayer coverage) on the catalytic activity of three supported Re active phases (Re, ReOx and ReSx for guaiacol conversion was studied. A 10 wt.% loading of Re was impregnated into CeO2-Al2O3 support and used to prepare...

Full description

Saved in:
Bibliographic Details
Published inApplied catalysis. A, General Vol. 547; p. 256
Main Authors Alvarez, C, Cruces, K, Garcia, R, Sepulveda, C, Fierro, JLG, Ghampson, IT, Escalona, N
Format Journal Article
LanguageEnglish
Published Amsterdam Elsevier Science SA 25.10.2017
Subjects
Acidity
Alumina
Aluminum oxide
Catalysis
Catalysts
Catalytic activity
Cerium oxides
Conversion
Deoxygenation
Phases
Rhenium
Sulfidation
Online AccessGet full text

Cover

More Information
Summary:The effect of Al2O3 modification by CeO2 addition (14 wt.% to obtain a maximum monolayer coverage) on the catalytic activity of three supported Re active phases (Re, ReOx and ReSx for guaiacol conversion was studied. A 10 wt.% loading of Re was impregnated into CeO2-Al2O3 support and used to prepare the three rhenium active phases by calcination, reduction or sulfidation steps. The catalysts were characterized by different techniques in order to explain the catalytic behavior of the solids studied. The catalysts were then evaluated in a batch reactor at 300 °C and 5 MPa of H2. The characterization results showed that the addition of CeO2 modified the acidity of the support as well as the metal-support interaction, and consequently the catalytic activity. In fact, CeO2 addition doubled the activity of Re and ReSx catalysts in comparison to the corresponding y-Al2O3-supported catalysts. These results were attributed to a higher dispersion of active sites in the case of metallic Re catalyst and higher concentration of non-stoichiometric sulfur species (ReS2-x) in the case of ReSx catalyst. On the other hand, a similar catalytic activity was observed over the two supported ReOx catalysts, indicating that the role of ReOx active phase on guaiacol conversion outweighs structural and surface modification induced by CeO2 addition. In relation to products distribution, it was observed that CeO2 addition enhanced phenol formation and generally led to higher degree of deoxygenation which is most likely related to decrease in acidity.
ISSN:0926-860X
1873-3875