Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone
New catalysts containing phosphomolybdic acid (PMA) and vanadophosphomolybdic acid (VPMA) in a titania matrix were synthesized by the sol–gel process with different heteropolyacid loads (5%, 15%, and 30% (w/w): 5PMA-TiO2, 15PMA-TiO2, 30PMA-TiO2, 5VPMA-TiO2, 15VPMA-TiO2, and 30VPMA-TiO2). The techniq...
Autores principales: | , , , |
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Formato: | Articulo |
Lenguaje: | Inglés |
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2020
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Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/132845 |
Aporte de: |
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I19-R120-10915-132845 |
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institution |
Universidad Nacional de La Plata |
institution_str |
I-19 |
repository_str |
R-120 |
collection |
SEDICI (UNLP) |
language |
Inglés |
topic |
Química Titania-heteropolyacid composite Sol–gel Green oxidation Hydrogen peroxide Benzoquinone |
spellingShingle |
Química Titania-heteropolyacid composite Sol–gel Green oxidation Hydrogen peroxide Benzoquinone Palacio, Magdalena Villabrille, Paula Isabel Palermo, Valeria Romanelli, Gustavo Pablo Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
topic_facet |
Química Titania-heteropolyacid composite Sol–gel Green oxidation Hydrogen peroxide Benzoquinone |
description |
New catalysts containing phosphomolybdic acid (PMA) and vanadophosphomolybdic acid (VPMA) in a titania matrix were synthesized by the sol–gel process with different heteropolyacid loads (5%, 15%, and 30% (w/w): 5PMA-TiO2, 15PMA-TiO2, 30PMA-TiO2, 5VPMA-TiO2, 15VPMA-TiO2, and 30VPMA-TiO2). The techniques used to characterize the materials were XRD, DRS, SEM, FT-IR, 31P MAS-NMR, potentiometric titration with n-butylamine, and N2 physisorption at −196 °C. The materials were used as heterogeneous catalysts in the oxidation of 2,3,6-trimethylphenol (TMP) to 2,3,5-trimethyl-p-benzoquinone (TMBQ), a key intermediate in vitamin E synthesis. The catalysts allowed an ecofriendly TMBQ synthesis, using ethanol as solvent and aqueous hydrogen peroxide as a clean oxidizing agent, at room temperature. The conversion of TMP reached 90% and 99% for the samples with 15PMA-TiO2 and 15VPMA-TiO2, respectively, after 4 h. The amount of Mo and V in the reaction medium was determined by ICP-MS, which showed leaching of only 17–18% Mo, but 48% V. Reuse of the catalysts was performed. For 15PMA-TiO2, the conversion was maintained in the second cycle. A homolytic mechanism was proposed for TMBQ synthesis, which involved the formation of a peroxometallic species through an HPA-Ti center. |
format |
Articulo Articulo |
author |
Palacio, Magdalena Villabrille, Paula Isabel Palermo, Valeria Romanelli, Gustavo Pablo |
author_facet |
Palacio, Magdalena Villabrille, Paula Isabel Palermo, Valeria Romanelli, Gustavo Pablo |
author_sort |
Palacio, Magdalena |
title |
Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
title_short |
Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
title_full |
Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
title_fullStr |
Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
title_full_unstemmed |
Titania-heteropolyacid composites (TiO2-HPA) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
title_sort |
titania-heteropolyacid composites (tio2-hpa) as catalyst for the green oxidation of trimethylphenol to 2,3,5-trimethyl-p-benzoquinone |
publishDate |
2020 |
url |
http://sedici.unlp.edu.ar/handle/10915/132845 |
work_keys_str_mv |
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bdutipo_str |
Repositorios |
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1764820454381453312 |