Samenvatting
The selectivity of the methanol-to-hydrocarbons (MTH) reaction can be tuned by modifying zeolite catalysts with alkaline earth metals, which typically increase propylene selectivity and catalyst stability. Here we employed Sr2+ as its higher atomic number in comparison to the zeolite T atoms facilitates characterization by scanning transmission electron microscopy and operando X-ray absorption spectroscopy. Sr2+ dispersed in the ZSM-5 micropores coordinates water, methanol, and dimethyl ether during the MTH reaction. Complementary characterization with nuclear magnetic resonance spectroscopy, thermogravimetric analysis combined with mass spectrometry, operando infrared spectroscopy, and X-ray diffraction points to the retention of substantially more adsorbates during the MTH reaction in comparison to Sr-free zeolites. Our findings support the notion that alkaline earth metals modify the porous reaction environment such that the olefin cycle is favored over the aromatic cycle in the MTH, explaining the increased propylene yield and lower deactivation rate.
Originele taal-2 | Engels |
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Pagina's (van-tot) | 6506-6512 |
Aantal pagina's | 7 |
Tijdschrift | Journal of Physical Chemistry Letters |
Volume | 14 |
Nummer van het tijdschrift | 28 |
DOI's | |
Status | Gepubliceerd - 20 jul. 2023 |
Financiering
Petra III Funding numbers: AV-2021024881
Financiers | Financiernummer |
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Shanghai Key-Laboratory of HREM | 21DZ2260400 |
European Union’s Horizon Europe research and innovation programme | |
H2020 Marie Skłodowska-Curie Actions | 801359, 823717-ESTEEM3 |
European Synchrotron Radiation Facility | CH6231 |
National Natural Science Foundation of China | NSFC-21835002, EM02161943 |
Ministerie van OCW | |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek | |
Ministerio de Ciencia e Innovación | DGA E13_20R, RYC2018-024561-I |
Helmholtz Association | |
ShanghaiTech University |