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CMK-3 carbon replica was synthesized by carbonization of sucrose introduced to the pore system of a SBA- 15 hard template followed by dissolving SiO 2 with HF. The material with a stable hexagonal structure and an expanded surface area ( S BET = 1287 m 2 /g) was obtained. TG measurements showed that CMK-3 type mesoporous carbon started to be intensively oxidized by molecular O 2 above 723 K. This carbon sample was tested as a catalyst of dehydrogenation of propane to propene under oxidative (O 2 :C 3 H 8 = 0.25, 0.50 and 1.00) and non-oxidative (O 2 :C 3 H 8 = 0.00) conditions in the temperature range from 573 to 873 K. The propene yield increased with rise in the reaction temperature, however above 573 K the formation of side- products (C 2 H 6 , C 2 H 4 , CH 4 and H 2 ) was observed. Moreover, coke was deposited on the catalyst surface. A decrease in the mass of a catalyst bed after the catalytic runs suggested the participation of oxygen in burning of deposited and bulk coke. The surface composition of a spent catalyst was investigated by XPS and TPD analysis. The changes in the concentration of oxygen functional groups, caused by the catalytic reaction, were observed regardless of a reaction temperature and feed composition. |
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