Isobutene Transformation to Aromatics on Zn-Modified Zeolite: Particular Effects of Zn2+ and ZnO Species on the Reaction Occurrence Revealed with Solid-State NMR and FTIR Spectroscopy Full article
| Journal |
The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455 |
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| Output data | Year: 2021, Volume: 125, Number: 28, Pages: 15343–15353 Pages count : 11 DOI: 10.1021/acs.jpcc.1c04249 | ||||
| Tags | Aromatic hydrocarbons; Aromatization; Butenes; Fourier transform infrared spectroscopy; II-VI semiconductors; Metadata; Mineral oils; Nuclear magnetic resonance spectroscopy; Olefins; Oligomers; Oxide minerals; Positive ions; Reaction intermediates; Zeolites; Zinc; Zinc oxide | ||||
| Authors |
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| Affiliations |
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Funding (2)
| 1 |
Russian Science Foundation German Research Foundation |
19-43-04101 |
| 2 | German Research Foundation | HA 1893/22-1 |
Abstract:
The effect of Zn2+ cations and small clusters of ZnO on isobutene transformation to aromatic hydrocarbons on Zn-modified zeolites (Zn2+/H-ZSM-5 and ZnO/H-BEA) has been investigated with 13C MAS NMR and FTIR spectroscopic techniques. It is inferred that isobutene is mainly stabilized in the form of a π-complex with Zn2+ cations of the Zn2+/H-ZSM-5 zeolite at 296–573 K, whereas the oligomerization of the olefin on Brønsted acid sites (BAS) of ZnO/H-BEA occurs at 296 K. Using isobutene, selectively labeled with the 13C isotope in either ═CH2 or ═C< groups, for NMR analysis of the evolution of the adsorbed species with temperature, the reaction intermediates have been identified within the temperature range of 296–623 K. At 296 K, an occurrence of the double-bond shift reaction in isobutene on Zn2+/H-ZSM-5 and a complete 13C-label scrambling in the oligomers formed on ZnO/H-BEA have been established. The detected intermediates include a π-complex of the olefin with Zn species, 2-methyl-σ-allylzinc species, isobutene oligomers, and delocalized carbanionic species. It is found that similar intermediates are formed in the course of the reaction on both zeolites at T ≥ 473 K, which implies that similar pathways of isobutene transformation are realized on the zeolites with different Zn species. An analysis of FTIR data reveals that the intermediate species formed on the Zn2+/H-ZSM-5 zeolite interact with both BAS and Zn sites at each of the reaction steps of the olefin transformation to aromatic hydrocarbons.
Cite:
Gabrienko A.A.
, Lashchinskaya Z.N.
, Arzumanov S.S.
, Toktarev A.V.
, Freude D.
, Haase J.
, Stepanov A.G.
Isobutene Transformation to Aromatics on Zn-Modified Zeolite: Particular Effects of Zn2+ and ZnO Species on the Reaction Occurrence Revealed with Solid-State NMR and FTIR Spectroscopy
The Journal of Physical Chemistry C. 2021. V.125. N28. P.15343–15353. DOI: 10.1021/acs.jpcc.1c04249 WOS Scopus РИНЦ AN OpenAlex
Isobutene Transformation to Aromatics on Zn-Modified Zeolite: Particular Effects of Zn2+ and ZnO Species on the Reaction Occurrence Revealed with Solid-State NMR and FTIR Spectroscopy
The Journal of Physical Chemistry C. 2021. V.125. N28. P.15343–15353. DOI: 10.1021/acs.jpcc.1c04249 WOS Scopus РИНЦ AN OpenAlex
Dates:
| Submitted: | May 13, 2021 |
| Accepted: | Jun 28, 2021 |
| Published online: | Jul 14, 2021 |
| Published print: | Jul 22, 2021 |
Identifiers:
| Web of science: | WOS:000677581600024 |
| Scopus: | 2-s2.0-85111184419 |
| Elibrary: | 46976163 |
| Chemical Abstracts: | 2021:1527956 |
| OpenAlex: | W3182858068 |