Ethylbenzene Dehydrogenation into Styrene: Kinetic Modeling and Reactor Simulation

A set of intrinsic rate equations based on the Hougen—Watson formalism was derived for the dehydrogenation of ethylbenzene into styrene on a commercial potassium-promoted iron catalyst. The model discrimination and parameter estimation was based on an extensive set of experiments that were conducted in a tubular reactor. Experimental data were obtained for a range of temperatures, space times, and feed molar ratios of steam to ethylbenzene, styrene to ethylbenzene, and hydrogen to ethylbenzene. All the estimated parameters satisfied the statistical tests and physicochemical criteria, and the kinetic model yielded an excellent fit of the experimental data. The model was applied in the simulation of the dehydrogenation in industrial multibed adiabatic reactors with either axial or radial flow and accounting also for thermal radical-type reactions, internal diffusion limitations, coke formation, and gasification.