In Situ Laser Raman Spectroscopy Studies of VPO Catalyst Transformations

Zhi Yang Xue, Glenn L Schrader

Research output: Contribution to journalArticle

57 Citations (Scopus)

Abstract

VPO catalyst transformations were investigated using in situ laser Raman spectroscopy. During reduction -oxidation step changes, (VO)2P2O7 was readily converted to αII-, δ-VOPO4, and ultimately to β-VOPO4 in O2/N2; these V5+ phases were eliminated in n-butane/N2. A wet N2 feed (5-10% H2O in N2) transformed (VO)2P2O7 and αI-, αII-, β-, δ-, γ-VOPO4 to V2O5 at temperatures above 400°C. The presence of water vapor facilitated the loss of oxygen atoms involved in V - O - P bonding, and separated vanadium oxide and phosphorus oxide species were formed. The isolated vanadium oxide species could be transformed to V2O5; phosphorus species likely diffused from the catalyst lattice in the form of acid phosphates.

Original languageEnglish (US)
Pages (from-to)9459-9467
Number of pages9
JournalJournal of Physical Chemistry B
Volume103
Issue number44
StatePublished - Nov 4 1999
Externally publishedYes

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Laser spectroscopy
vanadium oxides
laser spectroscopy
Oxides
Raman spectroscopy
Vanadium
phosphorus oxides
catalysts
Phosphorus
Catalysts
butanes
water vapor
phosphorus
oxygen atoms
phosphates
Steam
Butane
Water vapor
oxidation
acids

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

In Situ Laser Raman Spectroscopy Studies of VPO Catalyst Transformations. / Xue, Zhi Yang; Schrader, Glenn L.

In: Journal of Physical Chemistry B, Vol. 103, No. 44, 04.11.1999, p. 9459-9467.

Research output: Contribution to journalArticle

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