Oxidative dehydrogenation of ethylbenzene on activated carbon catalysts. I. Influence of surface chemical groups

Activated carbons were used as catalysts for the oxidative dehydrogenation of ethylbenzene, The type and amount of functional groups on the surface of the carbon catalysts was modified by oxidative treatments in the gas or in the liquid phase, while heat treatments at different temperatures were use d to selectively remove some of the functional groups. The performance of t hese catalysts was evaluated in terms of conversion, styrene yield and sele ctivity. The results show that the gas phase treatments lead to improved pe rformance associated with an increase in the amount of carbonyl/quinone gro ups on the surface, which were identified as the active sites for the react ion. A good correlation between catalytic activity and the concentration of these surface groups was obtained. (C) 1999 Elsevier Science B.V. All righ ts reserved.