EXAFS (extended x-ray absorption fine structure spectroscopy) investigation of vanadium-phosphorus catalysts with different P/V ratios

Journal Article · Sun Apr 01 00:00:00 EST 1990 · Journal of Catalysis; (USA)

DOI:https://doi.org/10.1016/0021-9517(90)90285-R· OSTI ID:6188552

Vlaic, G; Garbassi, F ^[1]

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1. Istituto Guido Donegani S.p.A., Novara (Italy)

Vanadium-phosphorus catalysts with different P/V ratios (0.93-1.28) have been investigated by EXAFS and XANES applied to the K-edge region of vanadium. When looked at from the pre-edge peak, vanadium appeared in the 4+ state after drying, while after calcination at 673 K both 4+ and 5+ states occurred simultaneously on samples with P/V > 1. EXAFS revealed that by changing chemical composition, structural variations occur around vanadium. On dried samples, the coordination number decreased from 5 to 4. On calcined samples, the longest V-O distance increased from 1.91 to 1.96 {angstrom}. The possible influence on the catalytic activity is discussed.

• OSTI ID: 6188552
• Journal Information: Journal of Catalysis; (USA), Vol. 122:2; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
02 PETROLEUM
CATALYSTS
CRYSTAL STRUCTURE
PHOSPHORUS
VANADIUM
ABSORPTION SPECTROSCOPY
BUTANE
CALCINATION
CATALYTIC EFFECTS
CHARGE STATES
CHEMICAL COMPOSITION
DRYING
OXIDATION
QUANTITY RATIO
VARIATIONS
X-RAY SPECTROSCOPY
ALKANES
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
HYDROCARBONS
METALS
NONMETALS
ORGANIC COMPOUNDS
PYROLYSIS
SPECTROSCOPY
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties
360102 - Metals & Alloys- Structure & Phase Studies
020400 - Petroleum- Processing