Vanadium antimonate as a partial oxidation catalyst

The catalytic selective oxidation on vanadium antimonate oxides partially doped with titanium was studied. Solids with nominal composition VSbO 4, V0.8SbTi0.2O4 and VSb 0.8Ti0.2O4 were prepared by solid-state reaction. The solids were characterised by sorptometry, X-ray diffraction (XRD), temperatur...

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Publicado: 2003
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Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0926860X_v250_n2_p279_Larrondo
http://hdl.handle.net/20.500.12110/paper_0926860X_v250_n2_p279_Larrondo
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spelling paper:paper_0926860X_v250_n2_p279_Larrondo2023-06-08T15:51:41Z Vanadium antimonate as a partial oxidation catalyst Titanium doping Toluene oxidation Vanadium antimonate Catalyst selectivity Composition effects Crystal lattices Doping (additives) Oxidation Redox reactions Reduction Thermal effects Toluene Vanadium compounds X ray diffraction analysis X ray photoelectron spectroscopy Temperature programmed reduction (TPR) Catalyst activity The catalytic selective oxidation on vanadium antimonate oxides partially doped with titanium was studied. Solids with nominal composition VSbO 4, V0.8SbTi0.2O4 and VSb 0.8Ti0.2O4 were prepared by solid-state reaction. The solids were characterised by sorptometry, X-ray diffraction (XRD), temperature programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS). Catalytic tests were carried out in a fixed-bed reactor using toluene and air as reactants. It was found that partial substitution of V or Sb by Ti produces changes in the unit-cell composition and the redox properties of the solids. A possible role for V and Sb in the reaction mechanism of partial oxidation was established. Vanadium sites (V4+) are involved in the incorporation of gaseous oxygen as lattice oxygen and hold the Sb sites in an oxidation state (Sb5+) high enough to insert the lattice oxygen in the hydrocarbon molecule. A relationship between activity and V 4+/Sb5+ ratio of the unit-cell was found. The selectivity to benzaldehyde is correlated with the redox properties of the solids while the selectivity to total oxidation products could be interpreted by the site isolation theory. © 2003 Elsevier Science B.V. All rights reserved. 2003 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0926860X_v250_n2_p279_Larrondo http://hdl.handle.net/20.500.12110/paper_0926860X_v250_n2_p279_Larrondo
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Titanium doping
Toluene oxidation
Vanadium antimonate
Catalyst selectivity
Composition effects
Crystal lattices
Doping (additives)
Oxidation
Redox reactions
Reduction
Thermal effects
Toluene
Vanadium compounds
X ray diffraction analysis
X ray photoelectron spectroscopy
Temperature programmed reduction (TPR)
Catalyst activity
spellingShingle Titanium doping
Toluene oxidation
Vanadium antimonate
Catalyst selectivity
Composition effects
Crystal lattices
Doping (additives)
Oxidation
Redox reactions
Reduction
Thermal effects
Toluene
Vanadium compounds
X ray diffraction analysis
X ray photoelectron spectroscopy
Temperature programmed reduction (TPR)
Catalyst activity
Vanadium antimonate as a partial oxidation catalyst
topic_facet Titanium doping
Toluene oxidation
Vanadium antimonate
Catalyst selectivity
Composition effects
Crystal lattices
Doping (additives)
Oxidation
Redox reactions
Reduction
Thermal effects
Toluene
Vanadium compounds
X ray diffraction analysis
X ray photoelectron spectroscopy
Temperature programmed reduction (TPR)
Catalyst activity
description The catalytic selective oxidation on vanadium antimonate oxides partially doped with titanium was studied. Solids with nominal composition VSbO 4, V0.8SbTi0.2O4 and VSb 0.8Ti0.2O4 were prepared by solid-state reaction. The solids were characterised by sorptometry, X-ray diffraction (XRD), temperature programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS). Catalytic tests were carried out in a fixed-bed reactor using toluene and air as reactants. It was found that partial substitution of V or Sb by Ti produces changes in the unit-cell composition and the redox properties of the solids. A possible role for V and Sb in the reaction mechanism of partial oxidation was established. Vanadium sites (V4+) are involved in the incorporation of gaseous oxygen as lattice oxygen and hold the Sb sites in an oxidation state (Sb5+) high enough to insert the lattice oxygen in the hydrocarbon molecule. A relationship between activity and V 4+/Sb5+ ratio of the unit-cell was found. The selectivity to benzaldehyde is correlated with the redox properties of the solids while the selectivity to total oxidation products could be interpreted by the site isolation theory. © 2003 Elsevier Science B.V. All rights reserved.
title Vanadium antimonate as a partial oxidation catalyst
title_short Vanadium antimonate as a partial oxidation catalyst
title_full Vanadium antimonate as a partial oxidation catalyst
title_fullStr Vanadium antimonate as a partial oxidation catalyst
title_full_unstemmed Vanadium antimonate as a partial oxidation catalyst
title_sort vanadium antimonate as a partial oxidation catalyst
publishDate 2003
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0926860X_v250_n2_p279_Larrondo
http://hdl.handle.net/20.500.12110/paper_0926860X_v250_n2_p279_Larrondo
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