The Methanol-to-Olefins (MTO) process is a highly promising route for producing light olefins, particularly ethylene and propylene, from methanol. This study presents a comprehensive micro-kinetic model that integrates molecular dynamics (MD) simulations with the Langmuir-Hinshelwood-Hougen-Watson (LHHW) formalism to predict the MTO process over the SAPO-34 catalyst. The model captures the complex reaction network involved in methanol conversion, including the formation of key intermediates such as methoxy, methylene, formaldehyde, and coke precursors. Through MD-derived minimum energy pathways (MEPs), the study identifies the energetics of critical reaction steps, including methanol activation, hydrocarbon pool (HCP) formation, and deactivation processes. The model provides quantitative insights into the formation rates of ethylene, propylene, and side products, while highlighting the role of surface vacancy concentration (θ v ) in regulating catalyst activity and selectivity. The accuracy of the model is validated by a low Mean Absolute Percentage Deviation (MAPD) of 6.6% and strong agreement with experimental data, demonstrating its predictive capability. The findings contribute to a deeper understanding of MTO chemistry and offer practical guidance for optimizing catalyst design, improving selectivity, and extending catalyst lifetimes in industrial MTO applications. • Integrated MD simulations and LHHW modeling for the MTO process over SAPO-34. • Identified key intermediates: methoxy, methylene, formaldehyde, and coke precursors. • Unraveled the MEP by analyzing reaction energies across all reaction steps.
Bagheri et al. (Tue,) studied this question.