Coupling of ethylbenzene dehydrogenation and benzene hydrogenation reactions in fixed bed catalytic reactors

The application of dual-functionality via a well-mixed catalyst pattern in an integrated fixed bed catalytic reactor for simultaneous production of styrene and cyclohexane has been investigated. A rigorous mathematical model based on the dusty gas model is used for the simulation. Equilibrium shifting is achieved by the drain-off mechanism of hydrogen in dehydrogenation–hydrogenation reaction media. The simulation results show that the fixed bed reactor (FBR) with auxiliary reactions achieves substantial increase in ethylbenzene conversion (≈100%) compared to the fixed bed reactor. Optimal conditions are observed and an effective length criterion for the optimal conditions is presented. The effects of the operating conditions on the reactor performance are examined. It seems that the overall performance of the reactor is a balance between the operating conditions and the rate of hydrogen removal. The results suggest that appreciable energy saving can be achieved by maintaining the reactor beds at different temperatures