A methanol to olefins review: Diffusion, coke formation and deactivation on SAPO type catalysts

The catalytic conversion of methanol to lower olefins (MTO) is a promising way of converting natural gas and coal to chemicals and fuels with methanol as an intermediate. Coke formation is a major cause of deactivation in the MTO processes and the present contribution deals with the progress on the study of adsorption, diffusion and reaction including deactivation due to coke formation during MTO. Design of SAPO-34 to achieve high activity and selectivity is discussed in terms of the two most important parameters, namely crystal size and operating temperatures.

Graphical abstract.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► SAPO-34 is still the most promising industrial catalyst for MTO. ► Crystal size is the most important parameter for catalyst design. ► Small sized SAPO-34 is required to avoid diffusion limitations for achieving low coke selectivity. ► Coke deposition has profound effects on product selectivity.