Structure of MoO3/Al2O3-SiO2 catalysts

Matthias Henker, Klaus Peter Wendlandt, J. Valyon, Peter Bornmann

Research output: Contribution to journalArticle

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Abstract

The structure of MoO3/Al2O3-SiO2 mixed oxide catalysts was studied by XRD, IR and UV-Vis spectroscopy. The nature of the Mo-O species formed depends on the composition of the amorphous Al2O3-SiO2 and is controlled by the inhomogeneity of the Al2O3-SiO2 carrier and the strong fixation of the molybdena on the separate alumina phase. The molybdenum is preferentially bound in the form of polymolybdates in the case of alumina-rich samples and as heteropolymolybdates or Al2(MoO4)3 in the case of silica-rich samples. The formation of heteropolymolybdates or Al2(MoO4)3 is due to the thermal instability of the amorphous Al2O3-SiO2. Introduction of molybdena generates new Brønsted acid sites on the surface of alumina-rich Al2O3-SiO2 supports. On the other hand no changes in Brønsted acidity induced by the molybdena has been found in catalysts with medium and low amounts of alumina.

Original languageEnglish
Pages (from-to)205-220
Number of pages16
JournalApplied Catalysis
Volume69
Issue number1
DOIs
Publication statusPublished - 1991

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Alumina
Catalysts
Ultraviolet spectroscopy
Acidity
Molybdenum
Silica
Oxides
Acids
Chemical analysis

Keywords

  • acidity.
  • catalyst characterization (IR
  • molybdenum oxide/alumina-silica
  • UV-Via
  • XRD)

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Structure of MoO3/Al2O3-SiO2 catalysts. / Henker, Matthias; Wendlandt, Klaus Peter; Valyon, J.; Bornmann, Peter.

In: Applied Catalysis, Vol. 69, No. 1, 1991, p. 205-220.

Research output: Contribution to journalArticle

Henker, M, Wendlandt, KP, Valyon, J & Bornmann, P 1991, 'Structure of MoO3/Al2O3-SiO2 catalysts', Applied Catalysis, vol. 69, no. 1, pp. 205-220. https://doi.org/10.1016/S0166-9834(00)83303-5
Henker, Matthias ; Wendlandt, Klaus Peter ; Valyon, J. ; Bornmann, Peter. / Structure of MoO3/Al2O3-SiO2 catalysts. In: Applied Catalysis. 1991 ; Vol. 69, No. 1. pp. 205-220.
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