Kinetic modeling formulation of the methanol to olefin process: Parameter estimation

• We develop a new kinetic scheme to describe the MTO process on a SAPO-34 catalyst.
• Rate constant and model parameters estimated with the method and experimental data.
• Increasing space-time favors the production of light olefins.
• Medium temperatures are favorable for maximizing total light olefins.
• Comparison between model and experimental data show that the developed scheme is statistically reliable.

Detailed kinetic models at the elementary step level were developed for the methanol to olefins (MTO) process over SAPO-34 catalyst. Starting from believable mechanisms, forming primary products was modeled rigorously by the Hougen–Watson formalism. Discrimination of kinetic equations and calculation of the parameters of best fit were performed by solving the mass conservation equations of the main products of the kinetic scheme. For rate constants, preexponential factors and apparent activation energies were then calculated according to the Arrhenius equation. For thermodynamic constants, the difference between apparent activation energies of forward and reverse reaction was considered. The kinetic model fits well the experimental data, which is obtained in a fixed bed reactor. The results showed that rising space-time is favorable for olefin yields while an optimum temperature might produce the maximum olefin.

In this study, detailed kinetic models at the elementary step level were developed for the methanol to olefins (MTO) process over SAPO-34 catalyst. To better understand the capability of the present modeling, a comparison test was applied to the experimental data. The obtained results demonstrate that the model is in good agreement with the experimental data. Results show that rising space-time is favorable for olefin yields while an optimum temperature can produce maximum olefin.Figure optionsDownload as PowerPoint slide