| 초록 |
Alkylaromatics hydrocarbons such as styrene, α-methylstyrene and divinylbenzenes are produced commercially by the vapor phase dehydrogenation of, correspondingly, ethylbenzene, isopropylbenzene and diethylbenzenes. These dehydrogenations are, however, thermodynamically limited and very energy consuming due to the required large excess of superheated steam and waste of its latent heat. Therefore lots of efforts have been for reduce it and replace with CO2. In this work, oxidative dehydrogenation of alkylaromatics with carbon dioxide has been carried out over supported vanadium oxide catalysts. Over V-Sb-O/Al2O3 catalyst, substantially higher (~ 20 - 60% in relative) conversions of initial hydrocarbons and yields of corresponding alkenylbenzenes have been achieved under the dehydrogenation of ethylbenzene, iso- and n-propylbenzenes, 1,4-diethylbenzene and 4-ethyltoluene in the presence of carbon dioxide, compared to those in inert atmosphere, due to promotional oxidative functions of CO2 to alleviate the dehydrogenation equilibrium as well as to maintain V-sites in active oxidation state, V5+. |
