Print Email Facebook Twitter Insights into the Activity and Deactivation of the Methanol-to-Olefins Process over Different Small-Pore Zeolites As Studied with Operando UV-vis Spectroscopy Title Insights into the Activity and Deactivation of the Methanol-to-Olefins Process over Different Small-Pore Zeolites As Studied with Operando UV-vis Spectroscopy Author Goetze, Joris (Debye Institute) Meirer, Florian (Debye Institute) Yarulina, I. (TU Delft ChemE/Catalysis Engineering) Gascon, Jorge (TU Delft ChemE/Catalysis Engineering) Kapteijn, F. (TU Delft ChemE/Catalysis Engineering) Ruiz-Martínez, Javier (Debye Institute) Weckhuysen, Bert M. (Debye Institute) Date 2017-06-02 Abstract The nature and evolution of the hydrocarbon pool (HP) species during the Methanol-to-Olefins (MTO) process for three small-pore zeolite catalysts, with a different framework consisting of large cages interconnected by small eight-ring windows (CHA, DDR, and LEV) was studied at reaction temperatures between 350 and 450 °C using a combination of operando UV-vis spectroscopy and online gas chromatography. It was found that small differences in cage size, shape, and pore structure of the zeolite frameworks result in the generation of different hydrocarbon pool species. More specifically, it was found that the large cage of CHA results in the formation of a wide variety of hydrocarbon pool species, mostly alkylated benzenes and naphthalenes. In the DDR cage, 1-methylnaphthalene is preferentially formed, while the small LEV cage generally contains fewer hydrocarbon pool species. The nature and evolution of these hydrocarbon pool species was linked with the stage of the reaction using a multivariate analysis of the operando UV-vis spectra. In the 3-D pore network of CHA, the reaction temperature has only a minor effect on the performance of the MTO catalyst. However, for the 2-D pore networks of DDR and LEV, an increase in the applied reaction temperature resulted in a dramatic increase in catalytic activity. For all zeolites in this study, the role of the hydrocarbon species changes with reaction temperature. This effect is most clear in DDR, in which diamantane and 1-methylnaphthalene are deactivating species at a reaction temperature of 350 °C, whereas at higher temperatures diamantane formation is not observed and 1-methylnaphthalene is an active species. This results in a different amount and nature of coke species in the deactivated catalyst, depending on zeolite framework and reaction temperature. Subject chemometricscoke formationdeactivationmethanol-to-olefinsoperandoUV-vis spectroscopyzeolites To reference this document use: http://resolver.tudelft.nl/uuid:a4938800-f79b-4b18-b46b-8568ea4141c1 DOI https://doi.org/10.1021/acscatal.6b03677 ISSN 2155-5435 Source ACS Catalysis, 7 (6), 4033-4046 Part of collection Institutional Repository Document type journal article Rights © 2017 Joris Goetze, Florian Meirer, I. Yarulina, Jorge Gascon, F. Kapteijn, Javier Ruiz-Martínez, Bert M. Weckhuysen Files PDF acscatal.6b03677_1.pdf 5.49 MB Close viewer /islandora/object/uuid:a4938800-f79b-4b18-b46b-8568ea4141c1/datastream/OBJ/view