Barothermal Synthesis and Catalytic Properties of Vanadium-Phosphorus Oxide Systems in Oxidative Transformations of Butane and Ethane

摘要

It was shown that under the conditions of barothermal synthesis of vanadium-phosphorus oxide catalysts the individual vanadium oxide phase VOHPO4 center dot 0.5 H2O is only formed in the n-butanol medium. The duration of the synthesis has a substantial effect on the surface morphology of the samples; with increase of the synthesis time structures of "rose" type are twisted and form "plaits." The "rose" type structures have high activity and selectivity in the oxidation of n-butane (1.5-1.7 vol.% in air). With hydrocarbon contents of 3.4 vol.% structures of the "plait" type are more effective, which makes recycling possible. Catalysts with the "plait" morphology are also more effective in the oxidative dehydrogenation of ethane.