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Dehydrogenation of propane to propylene in absence and in presence of oxygen in the reaction mixture of propane-inert gas has been investigated on vanadium oxide supported on mesoporous H-Ti-MCM-41 titanosilicate prepared by hydrothermal synthesis from titanoaerosil. It has been shown that at increase of the amount of VxOy from 5 to 30 wt. %, supported by decomposition of vanadyl oxalate or acetylacetonate complexes, the orderliness of system H-Ti-MCM-41 is broken, the size of its surface, diameter and volume of mesopores are decreased. The maximum yield of propylene is reached at 650-675 °C. It is obtained on 20 % greater for dehydrogenation of propane in the absence of oxygen. It is dependent extremally on the formed volume of pores, on its relationship with the acidity of active surface sites and it is accounted for the certain optimum range of variation of these values. [ABSTRACT FROM AUTHOR]

The influence of conditions for V2O5-MoO3 catalysts hydrothermal treatment (HTT) by conventional and microwave heating on their physico-chemical and catalytic properties has been studied. The observed transformations have been investigated by XRD, FTIR, nitrogen adsorption, measurements of electroconductivity. The activity V-Mo-O samples in reaction of oxidative dehydrogenation of propane increases in row HTT-300 °C > HTT-350 °C > HTT-250 °C according to changes of their conductivity G·10-5: 11 > 6 > 1 S/m. [ABSTRACT FROM AUTHOR]

Ti-MCM-41 silicate with vanadium introduced in mesoporous structure has been obtained by hydrothermal template synthesis with participation of VOSO4 and pyrogenic titanoaerosil with 1.4 wt. % tetrahedrally coordinated titanium. By the X-ray diffraction, X-ray fluorescent spectroscopy, DR UV-vis analysis and adsorption of nitrogen it has been shown that even 0.3 wt. % V causes raising spatial order and hydrolytic stability of Ti-MCM-41. It has been found that additional supporting of VOx groups on a surface of the synthesized bimetallic silicate allowed to obtain the catalyst 5 %VOx/V, Ti-MCM-41 which due to dehydrogenation of propane generated propylene with bigger selectivity and yield than those when VOx was supported on MCM-41 and Ti-MCM-41. [ABSTRACT FROM AUTHOR]