Development of a rigorous two-dimensional mathematical model for a novel thermally coupled reactor for simultaneous production of xylenes, hydrogen, and toluene

In this study, a novel reactor configuration has been proposed, in which the exothermic process of heavy aromatics upgrading to xylenes and endothermic process of dehydrogenation of methylcyclohexane to toluene and hydrogen are thermally coupled. Because of the existence of different components in the feedstock of the exothermic side, an elaborate kinetic model is applied to provide a reliable reactor model. A two-dimensional, comprehensive mathematical model is developed to predict the reactor performance, which is solved by means of finite difference method. The results indicate that by employing the coupled configuration, the xylenes and hydrogen production rates are improved, acceptably. Additionally, the effect of coupling of mass (recycling toluene from the endothermic side to the exothermic side) is investigated, which results in higher yield of xylenes in the first part of the reactor; while it lowers the xylenes yield in the second part.