Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst
- Autores
- Collins, Sebastián Enrique; Baltanas, Miguel Angel; Bonivardi, Adrian Lionel
- Año de publicación
- 2005
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- The thermal decomposition of adsorbed methanol on 2 wt.% Pd/silica, 2 wt.% Pd/gallia and pure gallia, was studied by temperatureprogrammed surface reaction (TPSR), between 323 and 723 K under He flow, using FT-IR spectroscopy. After methanol adsorption on Pd/silica at 323 K, the concentration of methoxy species on the silica decreased during the TPRS experiment, but some methoxy groups still remained on this support even at 723 K. Simultaneously, methanol decomposed over metallic palladium to yield, stepwise, HCO and CO with the consequent release of H2 (g). On clean gallia, methanol is Lewis-bound adsorbed to the surface, as well as dissociatively adsorbed as methoxy (CH3O), but the position of the infrared bands indicates a stronger interaction of these species on gallium oxide than on silica. Methoxy species on gallia are decomposed to (mono- and bi-dentate) formate groups (m- and b-HCOO, respectively) at T > 473 K. We suggest that CO and CO2 are further produced by nonstoichiometric transformation of these formates, leading to the release of atomic hydrogen on the surface of the oxide, as detected by the Ga–H stretching infrared band, and surface anion vacancies. In the presence of Pd on the gallia surface, the dehydrogenation of CH3O species proceeds faster than over the pure oxide, and we propose the following mechanism for methanol decomposition: (i) methanol reacts with OH groups on the gallia surface to produce water and methoxy species, (ii) the dehydrogenation of the latter carbonaceous group leads to H2COO, first, and then to mand b-HCOO, (iii) the hydrogen atoms released in the previous steps are transferred from gallia to the Pd surface where they recombine and desorb as H2 (g).
Fil: Collins, Sebastián Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina
Fil: Baltanas, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina
Fil: Bonivardi, Adrian Lionel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina - Materia
-
Methanol
Decomposition
Palladium
Gallia - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/26604
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Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalystCollins, Sebastián EnriqueBaltanas, Miguel AngelBonivardi, Adrian LionelMethanolDecompositionPalladiumGalliahttps://purl.org/becyt/ford/1.4https://purl.org/becyt/ford/1The thermal decomposition of adsorbed methanol on 2 wt.% Pd/silica, 2 wt.% Pd/gallia and pure gallia, was studied by temperatureprogrammed surface reaction (TPSR), between 323 and 723 K under He flow, using FT-IR spectroscopy. After methanol adsorption on Pd/silica at 323 K, the concentration of methoxy species on the silica decreased during the TPRS experiment, but some methoxy groups still remained on this support even at 723 K. Simultaneously, methanol decomposed over metallic palladium to yield, stepwise, HCO and CO with the consequent release of H2 (g). On clean gallia, methanol is Lewis-bound adsorbed to the surface, as well as dissociatively adsorbed as methoxy (CH3O), but the position of the infrared bands indicates a stronger interaction of these species on gallium oxide than on silica. Methoxy species on gallia are decomposed to (mono- and bi-dentate) formate groups (m- and b-HCOO, respectively) at T > 473 K. We suggest that CO and CO2 are further produced by nonstoichiometric transformation of these formates, leading to the release of atomic hydrogen on the surface of the oxide, as detected by the Ga–H stretching infrared band, and surface anion vacancies. In the presence of Pd on the gallia surface, the dehydrogenation of CH3O species proceeds faster than over the pure oxide, and we propose the following mechanism for methanol decomposition: (i) methanol reacts with OH groups on the gallia surface to produce water and methoxy species, (ii) the dehydrogenation of the latter carbonaceous group leads to H2COO, first, and then to mand b-HCOO, (iii) the hydrogen atoms released in the previous steps are transferred from gallia to the Pd surface where they recombine and desorb as H2 (g).Fil: Collins, Sebastián Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Baltanas, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Bonivardi, Adrian Lionel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaElsevier Science2005-12info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/26604Collins, Sebastián Enrique; Baltanas, Miguel Angel; Bonivardi, Adrian Lionel; Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst; Elsevier Science; Applied Catalysis A: General; 296; 2; 12-2005; 126-1330926-860XCONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1016/j.apcata.2005.07.053info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0926860X05005715info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:10:54Zoai:ri.conicet.gov.ar:11336/26604instacron: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:34982025-09-29 10:10:54.327CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
title |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
spellingShingle |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst Collins, Sebastián Enrique Methanol Decomposition Palladium Gallia |
title_short |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
title_full |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
title_fullStr |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
title_full_unstemmed |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
title_sort |
Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst |
dc.creator.none.fl_str_mv |
Collins, Sebastián Enrique Baltanas, Miguel Angel Bonivardi, Adrian Lionel |
author |
Collins, Sebastián Enrique |
author_facet |
Collins, Sebastián Enrique Baltanas, Miguel Angel Bonivardi, Adrian Lionel |
author_role |
author |
author2 |
Baltanas, Miguel Angel Bonivardi, Adrian Lionel |
author2_role |
author author |
dc.subject.none.fl_str_mv |
Methanol Decomposition Palladium Gallia |
topic |
Methanol Decomposition Palladium Gallia |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.4 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
The thermal decomposition of adsorbed methanol on 2 wt.% Pd/silica, 2 wt.% Pd/gallia and pure gallia, was studied by temperatureprogrammed surface reaction (TPSR), between 323 and 723 K under He flow, using FT-IR spectroscopy. After methanol adsorption on Pd/silica at 323 K, the concentration of methoxy species on the silica decreased during the TPRS experiment, but some methoxy groups still remained on this support even at 723 K. Simultaneously, methanol decomposed over metallic palladium to yield, stepwise, HCO and CO with the consequent release of H2 (g). On clean gallia, methanol is Lewis-bound adsorbed to the surface, as well as dissociatively adsorbed as methoxy (CH3O), but the position of the infrared bands indicates a stronger interaction of these species on gallium oxide than on silica. Methoxy species on gallia are decomposed to (mono- and bi-dentate) formate groups (m- and b-HCOO, respectively) at T > 473 K. We suggest that CO and CO2 are further produced by nonstoichiometric transformation of these formates, leading to the release of atomic hydrogen on the surface of the oxide, as detected by the Ga–H stretching infrared band, and surface anion vacancies. In the presence of Pd on the gallia surface, the dehydrogenation of CH3O species proceeds faster than over the pure oxide, and we propose the following mechanism for methanol decomposition: (i) methanol reacts with OH groups on the gallia surface to produce water and methoxy species, (ii) the dehydrogenation of the latter carbonaceous group leads to H2COO, first, and then to mand b-HCOO, (iii) the hydrogen atoms released in the previous steps are transferred from gallia to the Pd surface where they recombine and desorb as H2 (g). Fil: Collins, Sebastián Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Baltanas, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Bonivardi, Adrian Lionel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina |
description |
The thermal decomposition of adsorbed methanol on 2 wt.% Pd/silica, 2 wt.% Pd/gallia and pure gallia, was studied by temperatureprogrammed surface reaction (TPSR), between 323 and 723 K under He flow, using FT-IR spectroscopy. After methanol adsorption on Pd/silica at 323 K, the concentration of methoxy species on the silica decreased during the TPRS experiment, but some methoxy groups still remained on this support even at 723 K. Simultaneously, methanol decomposed over metallic palladium to yield, stepwise, HCO and CO with the consequent release of H2 (g). On clean gallia, methanol is Lewis-bound adsorbed to the surface, as well as dissociatively adsorbed as methoxy (CH3O), but the position of the infrared bands indicates a stronger interaction of these species on gallium oxide than on silica. Methoxy species on gallia are decomposed to (mono- and bi-dentate) formate groups (m- and b-HCOO, respectively) at T > 473 K. We suggest that CO and CO2 are further produced by nonstoichiometric transformation of these formates, leading to the release of atomic hydrogen on the surface of the oxide, as detected by the Ga–H stretching infrared band, and surface anion vacancies. In the presence of Pd on the gallia surface, the dehydrogenation of CH3O species proceeds faster than over the pure oxide, and we propose the following mechanism for methanol decomposition: (i) methanol reacts with OH groups on the gallia surface to produce water and methoxy species, (ii) the dehydrogenation of the latter carbonaceous group leads to H2COO, first, and then to mand b-HCOO, (iii) the hydrogen atoms released in the previous steps are transferred from gallia to the Pd surface where they recombine and desorb as H2 (g). |
publishDate |
2005 |
dc.date.none.fl_str_mv |
2005-12 |
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/11336/26604 Collins, Sebastián Enrique; Baltanas, Miguel Angel; Bonivardi, Adrian Lionel; Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst; Elsevier Science; Applied Catalysis A: General; 296; 2; 12-2005; 126-133 0926-860X CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/26604 |
identifier_str_mv |
Collins, Sebastián Enrique; Baltanas, Miguel Angel; Bonivardi, Adrian Lionel; Mechanism of the decomposition of adsorbed methanol over a Pd/α,β-Ga2O3 catalyst; Elsevier Science; Applied Catalysis A: General; 296; 2; 12-2005; 126-133 0926-860X 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.apcata.2005.07.053 info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0926860X05005715 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf application/pdf application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier Science |
publisher.none.fl_str_mv |
Elsevier Science |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
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CONICET Digital (CONICET) |
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CONICET Digital (CONICET) |
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Consejo Nacional de Investigaciones Científicas y Técnicas |
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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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13.070432 |