Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays
Autor(a) principal: | |
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Data de Publicação: | 2015 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.13/3217 |
Resumo: | In this study, we report the use of clay-based catalysts in the methoxylation of -pinene, for the selective synthesis of -terpinyl methyl ether, TME. The main reaction products and intermediates were identified by GC–MS. The reaction conditions (stirring rate and catalystload)that afford a kinetic regime were estab lished. SAz-1 (Cheto, Arizona, USA) source clay and a montmorillonite (SD) from Porto Santo, Madeira Archipelago, Portugal, were modified by ion-exchange with Al3+ to produce catalysts with markedly different acidities and textural properties. The catalysts based on the high layer-charge SAz-1 montmo rillonite proved to be the most active. Ion-exchange with Al3+, followed by thermal activation at 150 ◦C, afforded the highest number of Brønsted acid sites – a significant proportion of which were located in the clay gallery – and this coincided with the maximum catalytic activity. The influence of various reac tion conditions, to maximize -pinene conversion and selectivity, was studied over AlSAz-1. When the reaction was performed for 1 h at 60 ◦C, the conversion reached 65% with 65% selectivity towards the mono-ether, TME. Similar conversions and selectivities required up to 50 h over zeolites and other solid acid catalysts. The kinetic dependencies of this reaction on temperature and reagent concentration, over the selected clays were also investigated. It was established that, in the temperature and reagent con centration regime studied, the reaction was first order with respect to -pinene. The apparent activation energies over the two catalysts, calculated from Arrhenius plots, were almost identical at 72 kJ mol−1. |
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Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged claysIon-exchanged claysClay acidityCatalysisPineneMethoxylationTerpinyl methyl ethe.Faculdade de Ciências Exatas e da EngenhariaIn this study, we report the use of clay-based catalysts in the methoxylation of -pinene, for the selective synthesis of -terpinyl methyl ether, TME. The main reaction products and intermediates were identified by GC–MS. The reaction conditions (stirring rate and catalystload)that afford a kinetic regime were estab lished. SAz-1 (Cheto, Arizona, USA) source clay and a montmorillonite (SD) from Porto Santo, Madeira Archipelago, Portugal, were modified by ion-exchange with Al3+ to produce catalysts with markedly different acidities and textural properties. The catalysts based on the high layer-charge SAz-1 montmo rillonite proved to be the most active. Ion-exchange with Al3+, followed by thermal activation at 150 ◦C, afforded the highest number of Brønsted acid sites – a significant proportion of which were located in the clay gallery – and this coincided with the maximum catalytic activity. The influence of various reac tion conditions, to maximize -pinene conversion and selectivity, was studied over AlSAz-1. When the reaction was performed for 1 h at 60 ◦C, the conversion reached 65% with 65% selectivity towards the mono-ether, TME. Similar conversions and selectivities required up to 50 h over zeolites and other solid acid catalysts. The kinetic dependencies of this reaction on temperature and reagent concentration, over the selected clays were also investigated. It was established that, in the temperature and reagent con centration regime studied, the reaction was first order with respect to -pinene. The apparent activation energies over the two catalysts, calculated from Arrhenius plots, were almost identical at 72 kJ mol−1.ElsevierDigitUMaCatrinescu, C.Fernandes, C.Castilho, P.Breen, C.2021-03-29T14:03:41Z20152015-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.13/3217engCatrinescu, C., Fernandes, C., Castilho, P., & Breen, C. (2015). Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays. Applied Catalysis A: General, 489, 171-179.10.1016/j.apcata.2014.10.028info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-02-05T03:30:20Zoai:digituma.uma.pt:10400.13/3217Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T15:06:10.233167Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
title |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
spellingShingle |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays Catrinescu, C. Ion-exchanged clays Clay acidity Catalysis Pinene Methoxylation Terpinyl methyl ethe . Faculdade de Ciências Exatas e da Engenharia |
title_short |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
title_full |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
title_fullStr |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
title_full_unstemmed |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
title_sort |
Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays |
author |
Catrinescu, C. |
author_facet |
Catrinescu, C. Fernandes, C. Castilho, P. Breen, C. |
author_role |
author |
author2 |
Fernandes, C. Castilho, P. Breen, C. |
author2_role |
author author author |
dc.contributor.none.fl_str_mv |
DigitUMa |
dc.contributor.author.fl_str_mv |
Catrinescu, C. Fernandes, C. Castilho, P. Breen, C. |
dc.subject.por.fl_str_mv |
Ion-exchanged clays Clay acidity Catalysis Pinene Methoxylation Terpinyl methyl ethe . Faculdade de Ciências Exatas e da Engenharia |
topic |
Ion-exchanged clays Clay acidity Catalysis Pinene Methoxylation Terpinyl methyl ethe . Faculdade de Ciências Exatas e da Engenharia |
description |
In this study, we report the use of clay-based catalysts in the methoxylation of -pinene, for the selective synthesis of -terpinyl methyl ether, TME. The main reaction products and intermediates were identified by GC–MS. The reaction conditions (stirring rate and catalystload)that afford a kinetic regime were estab lished. SAz-1 (Cheto, Arizona, USA) source clay and a montmorillonite (SD) from Porto Santo, Madeira Archipelago, Portugal, were modified by ion-exchange with Al3+ to produce catalysts with markedly different acidities and textural properties. The catalysts based on the high layer-charge SAz-1 montmo rillonite proved to be the most active. Ion-exchange with Al3+, followed by thermal activation at 150 ◦C, afforded the highest number of Brønsted acid sites – a significant proportion of which were located in the clay gallery – and this coincided with the maximum catalytic activity. The influence of various reac tion conditions, to maximize -pinene conversion and selectivity, was studied over AlSAz-1. When the reaction was performed for 1 h at 60 ◦C, the conversion reached 65% with 65% selectivity towards the mono-ether, TME. Similar conversions and selectivities required up to 50 h over zeolites and other solid acid catalysts. The kinetic dependencies of this reaction on temperature and reagent concentration, over the selected clays were also investigated. It was established that, in the temperature and reagent con centration regime studied, the reaction was first order with respect to -pinene. The apparent activation energies over the two catalysts, calculated from Arrhenius plots, were almost identical at 72 kJ mol−1. |
publishDate |
2015 |
dc.date.none.fl_str_mv |
2015 2015-01-01T00:00:00Z 2021-03-29T14:03:41Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10400.13/3217 |
url |
http://hdl.handle.net/10400.13/3217 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Catrinescu, C., Fernandes, C., Castilho, P., & Breen, C. (2015). Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays. Applied Catalysis A: General, 489, 171-179. 10.1016/j.apcata.2014.10.028 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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