Results 171 to 180 of about 2,530 (217)

The Modification of VPO Catalyst Precursor and Characterization

Advanced Materials Research, 2011
Tween 60 and Tween 80 as dispersant had been adding in the preparation process to increase the surface area of VPO catalysts. XRD、 XPS and TEM characterization tests show that the crystalline phase and the catalyst surface area of adding surfactant Tween 60 and Tween 80 are different from that did not. Although the two types of crystalline phase are to
Yan Lin Zhang, Dian Hui Hou, Yang Zhou, Xi Wu Fan, Nai Di Tan   +4 more
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?????????????? ?????????????? ???? ????????????-???????????????????? ???????????????? ?????????????????????? VPO-????????????????????????

2009
?????????????? ?????????????? ?????????????????????????? ?????????????? (????, ??i, Te, Zr, La, Ti, W, Fe) ???? ????????????-???????????????????? ???????????????? ?????????????????????? VPO-??????????????????????????. ?????????????? ?????????????????????? ???????????????? ???????????????????????????? ???????????????? ??????????????, ????????????????????
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Synthesis of a novel mesoporous VPO compound

Chemical Communications, 1996
A novel mesoporous VPO compound is synthesized from VOHPO4·0.5H2O by intercalation of surfactant and subsequent hydrothermal treatment.
T. Doi, T. Miyake
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Characterization of cobalt-impregnated VPO catalysts

Catalysis Today, 2000
Abstract Cobalt-impregnated VPO catalysts containing 1–6% of the metal by weight were prepared. The catalytic tests showed that cobalt impregnation significantly increased the overall activity while slightly decreasing the maleic anhydride selectivity.
L.M. Cornaglia, C.R. Carrara, J.O. Petunchi, E.A. Lombardo   +3 more
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On the molecular weight determination by vapor pressure osmometry (VPO), 2. Molecular weight average obtained by VPO

Die Makromolekulare Chemie, 1980
AbstractProvided that in molecular weight determinations by vapor pressure osmometry (VPO) the relationship between M and the measured quantity (δV/c)c=0 obeys a calibration function of the type (δV/c)c=0 = KM−a, the kind of molecular weight average M̄VPO delivered by this method is derived. The deviation of M̄VPO from the true number average molecular
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Redox Properties of VPO Ammoxidation Catalysts

Chemical Engineering & Technology, 1999
The purpose of this study is to explore correlations between the molarity of V x IV/V O y proportions of (NH 4 ) 2 (V IV O) 3 (P 2 O 7 ) 2 catalysts, the vanadium valence states, and the reducibility of the vanadium on the one hand and the catalytic activity of the solids on the other. Pure (NH 4 ) 2 (V IV O) 3 (P 2 O 7 ) 2 and two ((NH 4 ) 2 (V IV
Andreas Martin, Bernhard Lücke
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Supported VPO Catalysts for Selective Oxidation of Butane. II. Characterization of VPO/SiO₂Catalysts

The Journal of Physical Chemistry B, 1997
SiO2-supported VPO catalysts with different P/V ratios were prepared, used in selective oxidation of butane, and characterized by X-ray diffraction (XRD), laser Raman spectroscopy (LRS), near-edge X-ray absorption spectroscopy (XANES), and 31P magic angle spinning NMR.
Kari E. Birkeland, Scott M. Babitz, Gregory K. Bethke, Harold H. Kung, George W. Coulston, Simon R. Bare   +5 more
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No x abatement over VPO catalysts

Catalysis Letters, 1993
Vanadium phosphorus oxide (P/V = 1.1) was found to be active for NO reduction by butane to N2 at 766–816 K. The conversion increased with increasing butane concentration, increasing temperature, and decreasing NO concentration. The activity per surface vanadium ion compared favorably with other active catalytic systems, but was low in the absence of ...
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On the Correlation of Structure and Catalytic Performance of VPO Catalysts

Topics in Catalysis, 2017
Correlations are reported between structure and performance of current, state-of the art, industrial maleic anhydride production catalysts. Characterization was done with fully equilibrated catalysts to achieve reliable correlations of structure and activity.
Sebastian Böcklein, Gerhard Mestl, Sabine Veronika Auras, Joost Wintterlin   +3 more
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Phase transformations in mesostructured VPO/surfactant composites

Microporous and Mesoporous Materials, 2004
Abstract Mesostructured VPO phases were obtained by soft-chemistry approaches in the presence of charged surfactants. These phases underwent phase transformations to various mesostructured and amorphous VPO phases during thermal treatment in N2 at 400 °C.
Moises A. Carreon, Vadim V. Guliants, M. Olga Guerrero-Pérez, Miguel A. Bañares   +3 more
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