Enhanced reaction lifetime of a bifunctional catalyst for methanol to olefins by combining formaldehyde decomposition on CeO2

A new bifunctional catalyst comprising of CeO2 and SSZ-13 physical mixture was developed, and its lifetime for the methanol to olefins (MTO) reaction was significantly enhanced. Formaldehyde adsorbed on ceria forms formate species, which decomposes to CO or CO2. The formaldehyde decomposition by CeO2 suppressed deposition of the inactive coke species formed (tetramethylnaphthalene), and improved the lifetime of SSZ-13 for MTO catalysis by 4-fold. The morphology of CeO2 has also an impact on the catalytic properties of the physical mixture catalyst, and the solid mixture of rod-like CeO2 and SSZ-13 showed the most extended stability.