Use of Graphite Nanofibers as a Catalyst for the Synthesis of Styrene

70002 Styrene, one of the ten most important industrial compounds, is produced by catalytic dehydrogenation of ethylbenzene. However, current catalysts undergo deactivation due to coke formation and thermal degradation. There are also environmental problems associated with the disposal of catalysts containing toxic substances such as chromium. Major benefits could be derived by using environmentally friendly catalysts that operate efficiently at lower temperatures and are resistant towards deactivation. Because certain types of carbon have been found to exhibit significant activity for the oxidative dehydrogenation of ethylbenzene to styrene at relatively low temperatures, this project will exploit the potential of tailored graphite nanofibers (GNF) as catalysts for this reaction. These materials possess the ideal blend of reaction sites required to optimize the catalyst performance, namely a well-defined mixture of basal plane and edge regions. Phase I will investigate the behavior of two types of GNF materials: one where the edge/basal plane ratio is very high, and the other where the reverse relationship exists. The performance of these materials will be compared to that of commercial catalyst systems operated under the same conditions. The key GNF structural parameters required to achieve optimum catalyst performance will be determined. Commercial Applications and Other Benefits as described by the awardee: Production of styrene is about 14 million tons worldwide, one third of which is generated in the U.S. The highly tailored GNF, produced from natural gas and used as the catalyst for the conversion of ethylbenzene to styrene, should reduce energy consumption, decrease product cost, and eliminate environmental problems associated with current technology.