A global methanol-to-hydrocarbons (MTH) model with H-ZSM-5 catalyst acidity descriptors

• Published in: Fuel (Guildford) 2024-12, Vol.378, p.132777, Article 132777
• Main Authors: Vicente, Héctor, Aguayo, Andrés T., Castaño, Pedro, Gayubo, Ana G.
• Format: Article
• Language: English
• Subjects: Catalytic descriptors; H-ZSM-5 zeolite; Lumped kinetic modeling; Methanol-to-hydrocarbons
• ISSN: 0016-2361
• DOI: 10.1016/j.fuel.2024.132777

•A unified kinetic model for MTH is developed using acidity descriptors.•The model is applicable to H-ZSM-5 zeolites of different acidity values.•The kinetic data is gathered from only 12 periodic experiments.•The model considers zero-time and deactivation kinetics.•The model is validated with simulations under MTA and MTO conditions. This work presents a dual cycle-based kinetic model that uses H-ZSM-5 catalyst acidity descriptors for the methanol-to-hydrocarbons (MTH, -olefins, MTO, and –aromatics, MTA) processes. This model was developed using data obtained in 12 periodic reactions with three H-ZSM-5 zeolites of different acidity (Si/Al = 15, 40 and 140). We decoupled the kinetics of the model from the catalyst identity by linking the calculation of the kinetic parameters to the zeolite acidity, allowing us to perform simulations of the reactor operating under various conditions and with different zeolite acidity values different from those used experimentally. The results obtained in the simulations let us identify the best operating conditions for the MTO and MTA processes, and pointed at the main difficulties found when implementing these two technologies industrially. In addition, the conditions and values obtained for the target products, either light olefins or aromatics, were comparable with those presented by several existing works in the literature for H-ZSM-5 zeolites of similar acidity. Moreover, the methodology detailed here using acidity descriptors can be extrapolated for its application to other catalytic processes.