Production of ethylene and cyclohexane in a catalytic membrane reactor

A rigorous two-dimensional mathematical model is used to simulate a bench-scale membrane reactor for ethane dehydrogenation to ethylene using a palladium-based membrane. Since the reaction is equilibrium limited the removal of the product hydrogen by the membrane shifts the thermodynamic equilibrium. For further displacement of the thermodynamic equilibrium, auxiliary hydrogenation reaction of benzene to cyclohexane over nickel catalyst is used to remove part of hydrogen. The two catalysts are loaded together in a well-mixed pattern configuration. Optimal conditions are observed and explanations offered. An effective length criterion for the optimal conditions is presented. The results show that the well-mixed pattern strategy has substantial improvement in the reactor performance in terms of high conversions, low temperatures and reduced mass of the catalyst used. The investigation, although is restricted to two catalyst, has uncovered a part of the rich characteristics of this system.