Chemistry, Physics and Technology of Surface, 2011, 2 (2), 164-170.

Properties of Supported Nanodispersed Tungsten Carbide Synthesized under Ultrasound Treatment



L. A. Vartikyan, V. T. Minasyan, V. A. Zazhigalov

Abstract


It has been shown that the modifying of the plasmochemical method by introduction of ultrasound vibrations leads to the synthesis of a nanodispersed tungsten carbide with narrow size distribution of particles (60 ± 10 nm). The supporting of nanodispersed tungsten carbide on alumina or clinoptylolite allows us to formation of nanostructures of active components on the support surface. The synthesized supported samples have high activity and selectivity in cyclohexane dehydrogenation. Use of ultrasound irradiation at the stage of active component supporting results in obtaining the high disperse active component and in its regular distribution over support surface. It has been shown that the deactivation of the samples in cyclohexane transformation reaction is connected with formation of carbon depositions on catalyst surface. Effective cleaning the surface and renovation of its catalytic properties can be realized via ultrasound treatment of the sample in aqueous or acetone medium. It has been found that such a treatment results in both carbon layer decomposition and formation of new structure of the sites active in cyclohexane dehydrogenation.

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