Dual-cycle-based lumped kinetic model for methanol-to-aromatics (MTA) reaction over H-ZSM-5 zeolites of different Si/Al ratio

In this work we developed a 7-lump kinetic model for the methanol-to-aromatics (MTA) reaction based on the dual-cycle mechanism, with consideration of deactivation of the catalyst by coke formation and applicable to H-ZSM-5 zeolite-based catalysts of different acidity. The model developed is suitable to be implemented at an industrial scale, as the intrinsic kinetic aspect fits the experimental data in a wide range of operating conditions. Moreover, the model is validated for two catalysts (prepared from two H-ZSM-5 zeolites of Si/Al ratio = 15 and 40), and considers a combined formation of coke from both unreacted oxygenates and reaction products (specifically, aromatics and light olefins). The final model comprises 10 reaction steps, and considers the effect of water co-feeding. The kinetic parameters of best fitting are obtained in the simultaneous fitting of the zero time and the deactivation kinetics. We compared the kinetic parameters of the best-fitting model for the two catalysts and related the differences obtained between both sets of parameters to catalyst properties.