Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts

Autores
Diez, Veronica Karina; Apesteguia, Carlos Rodolfo; Di Cosimo, Juana Isabel
Año de publicación
2006
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The liquid-phase synthesis of pseudoionones (PSs) by cross-aldol condensation of citral with acetone was studied on alkali-promoted MgO catalysts. Alkaline metals (A), including Li, Na, K, and Cs, were added to a high-surface area MgO in A/Mg molar ratios of up to 0.01. Promoters of greater ionic radius than Li blocked the catalyst pores of MgO, causing a decrease in both surface area and catalyst activity. In contrast, the addition of Li enhanced the PS yield of parent MgO. This beneficial effect of Li was further investigated by preparing, characterizing, and testing several Li/MgO catalysts with different Li loadings. The results were interpreted in terms of the structural, textural, and basic properties of the resulting oxides. Li loadings of up to 0.5 wt% increased the total base site density of parent MgO mainly by increasing the density of very active strong base sites (low coordination oxygen anions), and thereby promoted the PS formation rate. Increasing the Li concentration further caused particle agglomeration and formation of unreactive carbonates that block the active sites. The citral/acetone aldol condensation mechanism on Li-MgO catalysts was also investigated, and a Langmuir-Hinshelwood-Hougen-Watson kinetic expression was developed to account for the initial PS formation rate and to interpret experimental data. It was found that the rate-determining step is the abstraction of the α-proton from the acetone molecule that occurs on strong Brönsted base sites. A PS yield of 93% was obtained at 353 K with a catalyst/citral weight ratio of 0.2 for the 0.5 wt% Li/MgO catalyst at the end of the 6-h catalytic run.
Fil: Diez, Veronica Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
Fil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
Fil: Di Cosimo, Juana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
Materia
Acetone
Aldol Condensation
Alkaline Metals
Base Catalysis
Citral
Mgo
Pseudoionone Synthesis
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/74762
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/74762
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalystsDiez, Veronica KarinaApesteguia, Carlos RodolfoDi Cosimo, Juana IsabelAcetoneAldol CondensationAlkaline MetalsBase CatalysisCitralMgoPseudoionone Synthesishttps://purl.org/becyt/ford/2.4https://purl.org/becyt/ford/2The liquid-phase synthesis of pseudoionones (PSs) by cross-aldol condensation of citral with acetone was studied on alkali-promoted MgO catalysts. Alkaline metals (A), including Li, Na, K, and Cs, were added to a high-surface area MgO in A/Mg molar ratios of up to 0.01. Promoters of greater ionic radius than Li blocked the catalyst pores of MgO, causing a decrease in both surface area and catalyst activity. In contrast, the addition of Li enhanced the PS yield of parent MgO. This beneficial effect of Li was further investigated by preparing, characterizing, and testing several Li/MgO catalysts with different Li loadings. The results were interpreted in terms of the structural, textural, and basic properties of the resulting oxides. Li loadings of up to 0.5 wt% increased the total base site density of parent MgO mainly by increasing the density of very active strong base sites (low coordination oxygen anions), and thereby promoted the PS formation rate. Increasing the Li concentration further caused particle agglomeration and formation of unreactive carbonates that block the active sites. The citral/acetone aldol condensation mechanism on Li-MgO catalysts was also investigated, and a Langmuir-Hinshelwood-Hougen-Watson kinetic expression was developed to account for the initial PS formation rate and to interpret experimental data. It was found that the rate-determining step is the abstraction of the α-proton from the acetone molecule that occurs on strong Brönsted base sites. A PS yield of 93% was obtained at 353 K with a catalyst/citral weight ratio of 0.2 for the 0.5 wt% Li/MgO catalyst at the end of the 6-h catalytic run.Fil: Diez, Veronica Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Di Cosimo, Juana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaAcademic Press Inc Elsevier Science2006-06info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/74762Diez, Veronica Karina; Apesteguia, Carlos Rodolfo; Di Cosimo, Juana Isabel; Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts; Academic Press Inc Elsevier Science; Journal of Catalysis; 240; 2; 6-2006; 235-2440021-9517CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1016/j.jcat.2006.04.003info:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/S0021951706001199info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-nd/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-10T13:23:13Zoai:ri.conicet.gov.ar:11336/74762instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-10 13:23:13.456CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
title Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
spellingShingle Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
Diez, Veronica Karina
Acetone
Aldol Condensation
Alkaline Metals
Base Catalysis
Citral
Mgo
Pseudoionone Synthesis
title_short Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
title_full Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
title_fullStr Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
title_full_unstemmed Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
title_sort Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts
dc.creator.none.fl_str_mv Diez, Veronica Karina
Apesteguia, Carlos Rodolfo
Di Cosimo, Juana Isabel
author Diez, Veronica Karina
author_facet Diez, Veronica Karina
Apesteguia, Carlos Rodolfo
Di Cosimo, Juana Isabel
author_role author
author2 Apesteguia, Carlos Rodolfo
Di Cosimo, Juana Isabel
author2_role author
author
dc.subject.none.fl_str_mv Acetone
Aldol Condensation
Alkaline Metals
Base Catalysis
Citral
Mgo
Pseudoionone Synthesis
topic Acetone
Aldol Condensation
Alkaline Metals
Base Catalysis
Citral
Mgo
Pseudoionone Synthesis
purl_subject.fl_str_mv https://purl.org/becyt/ford/2.4
https://purl.org/becyt/ford/2
dc.description.none.fl_txt_mv The liquid-phase synthesis of pseudoionones (PSs) by cross-aldol condensation of citral with acetone was studied on alkali-promoted MgO catalysts. Alkaline metals (A), including Li, Na, K, and Cs, were added to a high-surface area MgO in A/Mg molar ratios of up to 0.01. Promoters of greater ionic radius than Li blocked the catalyst pores of MgO, causing a decrease in both surface area and catalyst activity. In contrast, the addition of Li enhanced the PS yield of parent MgO. This beneficial effect of Li was further investigated by preparing, characterizing, and testing several Li/MgO catalysts with different Li loadings. The results were interpreted in terms of the structural, textural, and basic properties of the resulting oxides. Li loadings of up to 0.5 wt% increased the total base site density of parent MgO mainly by increasing the density of very active strong base sites (low coordination oxygen anions), and thereby promoted the PS formation rate. Increasing the Li concentration further caused particle agglomeration and formation of unreactive carbonates that block the active sites. The citral/acetone aldol condensation mechanism on Li-MgO catalysts was also investigated, and a Langmuir-Hinshelwood-Hougen-Watson kinetic expression was developed to account for the initial PS formation rate and to interpret experimental data. It was found that the rate-determining step is the abstraction of the α-proton from the acetone molecule that occurs on strong Brönsted base sites. A PS yield of 93% was obtained at 353 K with a catalyst/citral weight ratio of 0.2 for the 0.5 wt% Li/MgO catalyst at the end of the 6-h catalytic run.
Fil: Diez, Veronica Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
Fil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
Fil: Di Cosimo, Juana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina
description The liquid-phase synthesis of pseudoionones (PSs) by cross-aldol condensation of citral with acetone was studied on alkali-promoted MgO catalysts. Alkaline metals (A), including Li, Na, K, and Cs, were added to a high-surface area MgO in A/Mg molar ratios of up to 0.01. Promoters of greater ionic radius than Li blocked the catalyst pores of MgO, causing a decrease in both surface area and catalyst activity. In contrast, the addition of Li enhanced the PS yield of parent MgO. This beneficial effect of Li was further investigated by preparing, characterizing, and testing several Li/MgO catalysts with different Li loadings. The results were interpreted in terms of the structural, textural, and basic properties of the resulting oxides. Li loadings of up to 0.5 wt% increased the total base site density of parent MgO mainly by increasing the density of very active strong base sites (low coordination oxygen anions), and thereby promoted the PS formation rate. Increasing the Li concentration further caused particle agglomeration and formation of unreactive carbonates that block the active sites. The citral/acetone aldol condensation mechanism on Li-MgO catalysts was also investigated, and a Langmuir-Hinshelwood-Hougen-Watson kinetic expression was developed to account for the initial PS formation rate and to interpret experimental data. It was found that the rate-determining step is the abstraction of the α-proton from the acetone molecule that occurs on strong Brönsted base sites. A PS yield of 93% was obtained at 353 K with a catalyst/citral weight ratio of 0.2 for the 0.5 wt% Li/MgO catalyst at the end of the 6-h catalytic run.
publishDate 2006
dc.date.none.fl_str_mv 2006-06
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/74762
Diez, Veronica Karina; Apesteguia, Carlos Rodolfo; Di Cosimo, Juana Isabel; Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts; Academic Press Inc Elsevier Science; Journal of Catalysis; 240; 2; 6-2006; 235-244
0021-9517
CONICET Digital
CONICET
url http://hdl.handle.net/11336/74762
identifier_str_mv Diez, Veronica Karina; Apesteguia, Carlos Rodolfo; Di Cosimo, Juana Isabel; Aldol condensation of citral with acetone on MgO and alkali-promoted MgO catalysts; Academic Press Inc Elsevier Science; Journal of Catalysis; 240; 2; 6-2006; 235-244
0021-9517
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jcat.2006.04.003
info:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/S0021951706001199
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Academic Press Inc Elsevier Science
publisher.none.fl_str_mv Academic Press Inc Elsevier Science
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 12.493442

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