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キーワード:
Catalyst, carbon composites, carbon fibers, scanning electron microscopy, X-ray photoelectron spectroscopy, catalytic properties
Carbon for selective oxidative dehydrogenation reactions
要旨:
Nanocarbons with macroscopic shaping have been studied as catalyst for the oxidative dehydogenation of ethylbenzene to styrene. Similarly to powdery nanocarbons, the catalyst exhibited high and stable performances, but without the detrimental drawbacks related to the use of fine powder form catalysts for technical applications in fixed-bed reactors. Carbon nanofibers were supported over a macroscopic graphite felt, using CCVD of ethane in the presence of hydrogen. The final material exhibits an open structure that avoids the limitations resulting from the powdery primary structure of nanocarbons. The ethylbenzene conversion can be significantly increased by increasing the space time, whereas a slight decrease in the selectivity to styrene was observed. A stable yield of 38% of styrene was obtained with a selectivity of 85% at 440ºC. Nor pressure drop neither moving-bed phenomena were observed what makes it attractive for gas-phase fixed-bed industrial applications.
