Modelling and optimization of simultaneous styrene and hydrogen production in an industrial hydrogen‐permselective membrane reactor

Abstract

Coupling reaction and separation in a membrane reactor improves process efficiency and reduces purification cost in the next stages. In this work, the performance of the hydrogen–permselective membrane reactors to produce styrene and hydrogen through ethylbenzene dehydrogenation is studied at steady state condition. In the proposed configuration, the Pd/Ag membrane tubes have been placed in the adiabatic reactors to remove hydrogen from the reaction zone. Then, the membrane reactors are modelled heterogeneously based on the mass and energy conservation laws considering a detailed thermal and catalytic kinetic model. To prove the accuracy of the considered model and assumptions, the simulation results of the conventional process are compared with the plant data. In addition, the genetic algorithm as a powerful method in the global optimization is applied to maximize the styrene production. The temperature of feed and sweep gas streams are attainable decision variables due to severe effect of temperature on the equilibrium and kinetic constant. This configuration has enhanced styrene production rate about 9.98 % compared to the industrial adiabatic reactor.