Abstract: Currently there is no agreement among the researchers worldwide about the mechanism of MFI-type zeolites deactivation due to coke accumulation in the areas of coke localization. This problem does not allow answering the question about the stability of these zeolites and their resistance to the reversible deactivation by coke. Our research provides the solution to this problem using physical and chemical methods: the electron paramagnetic resonance, X-ray photoelectron spectroscopy, thermal analysis and catalytic method of methanol conversion into hydrocarbons. We show that the key mechanism of coke formation is carbenium mechanism. Deactivation of zeolites occurs mainly due to the coke accumulation on the external surface of crystals of MFI-type zeolites. The contribution of “hydrocarbon pool” mechanism is negligibly small compared to the contribution of the carbenium mechanism of olefin formation by the dehydration reaction. This understanding allows increasing the stability of MFI type zeolites to coke formation by removing the acidic centres from the external surface of the crystals.

Cite: Echevsky G.V. , Echevskaya O.G.
Coking Mechanism and the Distribution of Agglomeration Products in High-Silica MFI-Type Zeolites
Chemistry for Sustainable Development. 2023. V.31. N1. P.20-31. DOI: 10.15372/CSD2023435 WOS РИНЦ OpenAlex

Original: Echevsky G.V. , Echevskaya O.G.
Coking Mechanism and the Distribution of Agglomeration Products in High-Silica MFI-Type Zeolites
Химия в интересах устойчивого развития. 2023. V.31. N1. P.20-31. DOI: 10.15372/khur2023435 РИНЦ AN OpenAlex

Dates:

Submitted:

Oct 27, 2022

Identifiers:

Web of science:	WOS:000992695300001
Elibrary:	50417734
OpenAlex:	W4361764333

Citing:

DB	Citing
Web of science	3

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