Kinetic modeling of ethylbenzene dehydrogenation over hydrotalcite catalysts

More than 80% of styrene is commercially produced by the catalytic dehydrogenation of ethylbenzene in the presence of large quantity of steam at elevated temperatures over iron oxide based catalysts promoted with alkaline ions. However, this process suffers from several drawbacks, e.g., high energy consumption and rapid catalytic deactivation. In light of this, the kinetics of ethylbenzene dehydrogenation was studied to elucidate the reaction mechanism. Reaction rates for the kinetics of ethylbenzene dehydrogenation were based on power law model with coke formation incorporated as a form of reactant conversion model. In developing the model equations, the most significant reactions were considered, i.e., dehydrogenation to styrene and cracking to yield benzene. All the estimated parameters were suitably correlated. The kinetic model yielded an excellent fit of the experimental data. For all the catalysts examined, ethylbenzene conversion increased with reaction temperature and time. This is an abstract of a paper submitted at the 21st Annual Saudi-Japan Symposium on Catalysts in Petroleum Refining and Petrochemicals (Dhahran, Saudi Arabia 11/27-28/2011).