Catalytic activity of carbon nanotubes and other carbon materials for oxidative dehydrogenation of ethylbenzene to styrene

摘要

Different carbons, i.e. carbon black, graphite and multiwalled nanotubes were tested as catalysts for oxidative dehydrogenation of ethylbenzene to styrene. The influence of the catalyst structure was determined on the catalytic activity and selectivity, and the catalyst stability in the oxidative dehydrogenation of ethylbenzene. In comparison to carbon black and graphite, multiwalled carbon nanotubes were found to exhibit the highest performance in the reaction. Carbon nanotubes as catalyst gave the highest styrene selectivity at maximum conversion. The characterization of the carbon nanotubes and the other carbon materials before and after the catalytic tests was conducted by several techniques, e.g. TEM, XRD and BET area measurements. This comparative characterization of the fresh and tested catalysts indicates that structural modifications in the nature of the catalysts occurred during the reaction. These modifications could be correlated with the changing catalytic behavior with time-on-stream.