Selective methoxylation of α-pinene to α-terpinyl methyl ether over Al3+ ion-exchanged clays

Detalhes bibliográficos
Autor(a) principal: Catrinescu, C.
Data de Publicação: 2015
Outros Autores: Fernandes, C., Castilho, P., Breen, C.
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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spelling 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
instname_str 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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