The activity of WO3-based mixed-oxide catalysts II. Activity and selectivity in oxidations of butene and butadiene
1977; Elsevier BV; Volume: 49; Issue: 3 Linguagem: Inglês
10.1016/0021-9517(77)90271-8
ISSN1090-2694
Autores Tópico(s)Oxidative Organic Chemistry Reactions
ResumoThe vapor-phase oxidation of 1-butene and butadiene was carried out over a series of WO3P2O5 catalysts, with different PW ratios, and over three series of WO3P2O5XnOm catalysts, with different kinds and amounts of the third component, XnOm. Pure WO3 is fairly inactive, and the introduction of a small amount (P = 1–5 atom%) of P2O5 into WO3 rapidly increases the activity, while the introduction of more than 10 atom% decreases the activity. The activity of the WO3P2O5 (PW = 28) catalyst increases markedly upon introduction of a small amount (5–10 atom%) of certain third components. The order of this promoting ability is found to be: V2O5 > CuO > Cr2O3 > MoO3 > Fe2O3. These catalysts show almost the same selectivity to maleic anhydride, whether the reactant is 1-butene or butadiene. The WO3P2O5-based catalysts are unsuitable for the selective oxidation of butene to butadiene and are inactive for the hydration of butene to an alcoholic intermediate, followed by oxydehydrogenation to form ketone or acetic acid. The catalytic behavior of the WO3P2O5-based catalysts in the oxidation can be associated with their acid-base properties; that is, they are highly acidic but scarcely basic.
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