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Cooperativity between Al Sites Promotes Hydrogen Transfer and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation on Alumina
[Image: see text] The methanol-to-olefin (MTO) process allows the conversion of methanol/dimethyl ether into olefins on acidic zeolites via the so-called hydrocarbon pool mechanism. However, the site and mechanism of formation of the first carbon–carbon bond are still a matter of debate. Here, we sh...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical Society
2015
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4827526/ https://www.ncbi.nlm.nih.gov/pubmed/27162986 http://dx.doi.org/10.1021/acscentsci.5b00226 |
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author | Comas-Vives, Aleix Valla, Maxence Copéret, Christophe Sautet, Philippe |
author_facet | Comas-Vives, Aleix Valla, Maxence Copéret, Christophe Sautet, Philippe |
author_sort | Comas-Vives, Aleix |
collection | PubMed |
description | [Image: see text] The methanol-to-olefin (MTO) process allows the conversion of methanol/dimethyl ether into olefins on acidic zeolites via the so-called hydrocarbon pool mechanism. However, the site and mechanism of formation of the first carbon–carbon bond are still a matter of debate. Here, we show that the Lewis acidic Al sites on the 110 facet of γ-Al(2)O(3) can readily activate dimethyl ether to yield CH(4), alkenes, and surface formate species according to spectroscopic studies combined with a computational approach. The carbon–carbon forming step as well as the formation of methane and surface formate involves a transient oxonium ion intermediate, generated by a hydrogen transfer between surface methoxy species and coordinated methanol on adjacent Al sites. These results indicate that extra framework Al centers in acidic zeolites, which are associated with alumina, can play a key role in the formation of the first carbon–carbon bond, the initiation step of the industrial MTO process. |
format | Online Article Text |
id | pubmed-4827526 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | American Chemical Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-48275262016-05-09 Cooperativity between Al Sites Promotes Hydrogen Transfer and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation on Alumina Comas-Vives, Aleix Valla, Maxence Copéret, Christophe Sautet, Philippe ACS Cent Sci [Image: see text] The methanol-to-olefin (MTO) process allows the conversion of methanol/dimethyl ether into olefins on acidic zeolites via the so-called hydrocarbon pool mechanism. However, the site and mechanism of formation of the first carbon–carbon bond are still a matter of debate. Here, we show that the Lewis acidic Al sites on the 110 facet of γ-Al(2)O(3) can readily activate dimethyl ether to yield CH(4), alkenes, and surface formate species according to spectroscopic studies combined with a computational approach. The carbon–carbon forming step as well as the formation of methane and surface formate involves a transient oxonium ion intermediate, generated by a hydrogen transfer between surface methoxy species and coordinated methanol on adjacent Al sites. These results indicate that extra framework Al centers in acidic zeolites, which are associated with alumina, can play a key role in the formation of the first carbon–carbon bond, the initiation step of the industrial MTO process. American Chemical Society 2015-08-05 2015-09-23 /pmc/articles/PMC4827526/ /pubmed/27162986 http://dx.doi.org/10.1021/acscentsci.5b00226 Text en Copyright © 2015 American Chemical Society This is an open access article published under an ACS AuthorChoice License (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html) , which permits copying and redistribution of the article or any adaptations for non-commercial purposes. |
spellingShingle | Comas-Vives, Aleix Valla, Maxence Copéret, Christophe Sautet, Philippe Cooperativity between Al Sites Promotes Hydrogen Transfer and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation on Alumina |
title | Cooperativity between Al Sites Promotes Hydrogen Transfer
and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation
on Alumina |
title_full | Cooperativity between Al Sites Promotes Hydrogen Transfer
and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation
on Alumina |
title_fullStr | Cooperativity between Al Sites Promotes Hydrogen Transfer
and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation
on Alumina |
title_full_unstemmed | Cooperativity between Al Sites Promotes Hydrogen Transfer
and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation
on Alumina |
title_short | Cooperativity between Al Sites Promotes Hydrogen Transfer
and Carbon–Carbon Bond Formation upon Dimethyl Ether Activation
on Alumina |
title_sort | cooperativity between al sites promotes hydrogen transfer
and carbon–carbon bond formation upon dimethyl ether activation
on alumina |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4827526/ https://www.ncbi.nlm.nih.gov/pubmed/27162986 http://dx.doi.org/10.1021/acscentsci.5b00226 |
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