Characterization of vanadium oxide-zirconia catalyst

Journal Article · Fri Mar 01 04:00:00 EST 1996 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1996.0076· OSTI ID:263783

Sohn, J R; Cho, Sung Guk ^[1]

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1. Kyungpook National Univ., Taegu (Korea, Republic of); and others

Vanadium oxide-zirconia catalysts were prepared by dry impregnation of powdered Zr(OH){sub 4} with an aqueous solution of NH{sub 4}VO{sub 3}. The surface characterization of prepared catalysts was performed using FTIR, DSC, {sup 51}V solid state NMR, and XRD, and by the measurement of surface area. The addition of vanadium oxide up to 9 mol% to zirconia shifted the phase transitions of ZrO{sub 2} from amorphous to tetragonal toward higher temperatures due to the interaction between vanadium oxide and zirconia. On the basis of results of IR, XRD, and DSC, it is concluded that the content of V{sub 2}O{sub 5} monolayer covering most of the available zirconia is 9 mol%, giving 2.3 V{sub 2}O{sub 5} molecules/nm{sup 2}. Since the ZrO{sub 2} dispersed vanadium oxide, the crystalline V{sub 2}O{sub 5} was observed only with the samples containing V{sub 2}O{sub 5} content exceeding the formation of complete monolayer (9 mol%) on the surface of ZrO{sub 2}. For the samples calcined at 673 K the acidity and surface area increase abruptly upon the addition of 0.2 mol% V{sub 2}O{sub 5} to ZrO{sub 2}, and then both of them increase with increasing V{sub 2}O{sub 5} content up to 5 mol%, showing the presence of Bronsted and Lewis acid sites on the V{sub 2}O{sub 5}/ZrO{sub 2} catalyst. 46 refs., 12 figs., 1 tab.

• OSTI ID: 263783
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 1 Vol. 159; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
ABSORPTION SPECTROSCOPY
BROENSTED ACIDS
CALORIMETRY
CATALYSTS
LEWIS ACIDS
NUCLEAR MAGNETIC RESONANCE
PHASE TRANSFORMATIONS
STRUCTURAL CHEMICAL ANALYSIS
SURFACE AREA
TETRAGONAL LATTICES
VANADIUM OXIDES
X-RAY DIFFRACTION
ZIRCONIUM OXIDES