Structure of alumina supported vanadia catalysts for oxidative dehydrogenation of propane prepared by flame spray pyrolysis

Martin Høj, Anker Degn Jensen, Jan-Dierk Grunwaldt

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

A series of five vanadia on alumina catalysts for oxidative dehydrogenation of propane to propene were synthesized by flame spray pyrolysis (FSP) using vanadium(III)acetylacetonate and aluminium(III)acetylacetonate dissolved in toluene as precursors. The vanadium loading was 2, 3, 5, 7.5 and 10wt.%. The catalysts were subsequently characterized by BET surface area, X-ray diffraction (XRD), Raman, UV–vis diffuse reflectance and X-ray absorption spectroscopy (XAS) as well as measurement of the catalytic performance. The catalysts had specific surface areas from 143 to 169 m2/g corresponding to average particles diameters from 9.0 to 10.9nm and apparent vanadia surface densities from 1.4 to 8.4 VOx/nm2. The only crystalline phase detected by XRD was γ-Al2O3, except at 10wt.% vanadium where traces of crystalline vanadia were observed. Raman spectroscopy showed vanadia monomers at 2 and 3wt.% V (1.4 and 2.1 VOx/nm2), a mixture of vanadia oligomers and monomers at 5wt.% V (3.6 VOx/nm2) and mainly oligomers at 7.5 and 10wt.% V (6.0 and 8.4 VOx/nm2). Diffuse reflectance UV–vis and extended X-ray absorption fine structure (EXAFS) spectroscopy measurements supported the results of Raman spectroscopy. In situ X-ray absorption near edge structure (XANES) spectroscopy showed that the vanadia can be reduced when operating at low oxygen concentrations. The catalyst performance was determined in fixed bed reactors with an inlet gas composition of C3H8/O2/N2=5/25/70. The main products were propene, CO and CO2, with traces of ethene and acrolein. Comparing propene selectivity as function of propane conversion the most selective catalysts were the 2 and 3wt.% V samples, which contained mostly vanadia monomers according to Raman spectroscopy. The best propene yield of 12% was obtained with the 2wt.% vanadium catalyst while the best space time yield of 0.78gpropene/(gcat·h) at 488°C was obtained with the 3wt.% V catalyst.
Original languageEnglish
JournalApplied Catalysis A: General
Volume451
Pages (from-to)207-215
ISSN0926-860X
DOIs
Publication statusPublished - 2013

Keywords

  • Flame spray pyrolysis
  • Vanadia
  • Oxidative dehydrogenation
  • Propane
  • Propene
  • Nanoparticle

Cite this

@article{f04898ec6cad47a18966e34b382ba683,
title = "Structure of alumina supported vanadia catalysts for oxidative dehydrogenation of propane prepared by flame spray pyrolysis",
abstract = "A series of five vanadia on alumina catalysts for oxidative dehydrogenation of propane to propene were synthesized by flame spray pyrolysis (FSP) using vanadium(III)acetylacetonate and aluminium(III)acetylacetonate dissolved in toluene as precursors. The vanadium loading was 2, 3, 5, 7.5 and 10wt.{\%}. The catalysts were subsequently characterized by BET surface area, X-ray diffraction (XRD), Raman, UV–vis diffuse reflectance and X-ray absorption spectroscopy (XAS) as well as measurement of the catalytic performance. The catalysts had specific surface areas from 143 to 169 m2/g corresponding to average particles diameters from 9.0 to 10.9nm and apparent vanadia surface densities from 1.4 to 8.4 VOx/nm2. The only crystalline phase detected by XRD was γ-Al2O3, except at 10wt.{\%} vanadium where traces of crystalline vanadia were observed. Raman spectroscopy showed vanadia monomers at 2 and 3wt.{\%} V (1.4 and 2.1 VOx/nm2), a mixture of vanadia oligomers and monomers at 5wt.{\%} V (3.6 VOx/nm2) and mainly oligomers at 7.5 and 10wt.{\%} V (6.0 and 8.4 VOx/nm2). Diffuse reflectance UV–vis and extended X-ray absorption fine structure (EXAFS) spectroscopy measurements supported the results of Raman spectroscopy. In situ X-ray absorption near edge structure (XANES) spectroscopy showed that the vanadia can be reduced when operating at low oxygen concentrations. The catalyst performance was determined in fixed bed reactors with an inlet gas composition of C3H8/O2/N2=5/25/70. The main products were propene, CO and CO2, with traces of ethene and acrolein. Comparing propene selectivity as function of propane conversion the most selective catalysts were the 2 and 3wt.{\%} V samples, which contained mostly vanadia monomers according to Raman spectroscopy. The best propene yield of 12{\%} was obtained with the 2wt.{\%} vanadium catalyst while the best space time yield of 0.78gpropene/(gcat·h) at 488°C was obtained with the 3wt.{\%} V catalyst.",
keywords = "Flame spray pyrolysis, Vanadia, Oxidative dehydrogenation, Propane, Propene, Nanoparticle",
author = "Martin H{\o}j and Jensen, {Anker Degn} and Jan-Dierk Grunwaldt",
year = "2013",
doi = "10.1016/j.apcata.2012.09.037",
language = "English",
volume = "451",
pages = "207--215",
journal = "Applied Catalysis A: General",
issn = "0926-860X",
publisher = "Elsevier",

}

Structure of alumina supported vanadia catalysts for oxidative dehydrogenation of propane prepared by flame spray pyrolysis. / Høj, Martin; Jensen, Anker Degn; Grunwaldt, Jan-Dierk.

In: Applied Catalysis A: General, Vol. 451, 2013, p. 207-215.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Structure of alumina supported vanadia catalysts for oxidative dehydrogenation of propane prepared by flame spray pyrolysis

AU - Høj, Martin

AU - Jensen, Anker Degn

AU - Grunwaldt, Jan-Dierk

PY - 2013

Y1 - 2013

N2 - A series of five vanadia on alumina catalysts for oxidative dehydrogenation of propane to propene were synthesized by flame spray pyrolysis (FSP) using vanadium(III)acetylacetonate and aluminium(III)acetylacetonate dissolved in toluene as precursors. The vanadium loading was 2, 3, 5, 7.5 and 10wt.%. The catalysts were subsequently characterized by BET surface area, X-ray diffraction (XRD), Raman, UV–vis diffuse reflectance and X-ray absorption spectroscopy (XAS) as well as measurement of the catalytic performance. The catalysts had specific surface areas from 143 to 169 m2/g corresponding to average particles diameters from 9.0 to 10.9nm and apparent vanadia surface densities from 1.4 to 8.4 VOx/nm2. The only crystalline phase detected by XRD was γ-Al2O3, except at 10wt.% vanadium where traces of crystalline vanadia were observed. Raman spectroscopy showed vanadia monomers at 2 and 3wt.% V (1.4 and 2.1 VOx/nm2), a mixture of vanadia oligomers and monomers at 5wt.% V (3.6 VOx/nm2) and mainly oligomers at 7.5 and 10wt.% V (6.0 and 8.4 VOx/nm2). Diffuse reflectance UV–vis and extended X-ray absorption fine structure (EXAFS) spectroscopy measurements supported the results of Raman spectroscopy. In situ X-ray absorption near edge structure (XANES) spectroscopy showed that the vanadia can be reduced when operating at low oxygen concentrations. The catalyst performance was determined in fixed bed reactors with an inlet gas composition of C3H8/O2/N2=5/25/70. The main products were propene, CO and CO2, with traces of ethene and acrolein. Comparing propene selectivity as function of propane conversion the most selective catalysts were the 2 and 3wt.% V samples, which contained mostly vanadia monomers according to Raman spectroscopy. The best propene yield of 12% was obtained with the 2wt.% vanadium catalyst while the best space time yield of 0.78gpropene/(gcat·h) at 488°C was obtained with the 3wt.% V catalyst.

AB - A series of five vanadia on alumina catalysts for oxidative dehydrogenation of propane to propene were synthesized by flame spray pyrolysis (FSP) using vanadium(III)acetylacetonate and aluminium(III)acetylacetonate dissolved in toluene as precursors. The vanadium loading was 2, 3, 5, 7.5 and 10wt.%. The catalysts were subsequently characterized by BET surface area, X-ray diffraction (XRD), Raman, UV–vis diffuse reflectance and X-ray absorption spectroscopy (XAS) as well as measurement of the catalytic performance. The catalysts had specific surface areas from 143 to 169 m2/g corresponding to average particles diameters from 9.0 to 10.9nm and apparent vanadia surface densities from 1.4 to 8.4 VOx/nm2. The only crystalline phase detected by XRD was γ-Al2O3, except at 10wt.% vanadium where traces of crystalline vanadia were observed. Raman spectroscopy showed vanadia monomers at 2 and 3wt.% V (1.4 and 2.1 VOx/nm2), a mixture of vanadia oligomers and monomers at 5wt.% V (3.6 VOx/nm2) and mainly oligomers at 7.5 and 10wt.% V (6.0 and 8.4 VOx/nm2). Diffuse reflectance UV–vis and extended X-ray absorption fine structure (EXAFS) spectroscopy measurements supported the results of Raman spectroscopy. In situ X-ray absorption near edge structure (XANES) spectroscopy showed that the vanadia can be reduced when operating at low oxygen concentrations. The catalyst performance was determined in fixed bed reactors with an inlet gas composition of C3H8/O2/N2=5/25/70. The main products were propene, CO and CO2, with traces of ethene and acrolein. Comparing propene selectivity as function of propane conversion the most selective catalysts were the 2 and 3wt.% V samples, which contained mostly vanadia monomers according to Raman spectroscopy. The best propene yield of 12% was obtained with the 2wt.% vanadium catalyst while the best space time yield of 0.78gpropene/(gcat·h) at 488°C was obtained with the 3wt.% V catalyst.

KW - Flame spray pyrolysis

KW - Vanadia

KW - Oxidative dehydrogenation

KW - Propane

KW - Propene

KW - Nanoparticle

U2 - 10.1016/j.apcata.2012.09.037

DO - 10.1016/j.apcata.2012.09.037

M3 - Journal article

VL - 451

SP - 207

EP - 215

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

SN - 0926-860X

ER -