Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina
Autor(a) principal: | |
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Data de Publicação: | 2017 |
Outros Autores: | , , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UnB |
Texto Completo: | http://repositorio.unb.br/handle/10482/30690 http://dx.doi.org/10.5935/0103-5053.20160183 |
Resumo: | This work deals with preparation and characterization of H3PW12O40 (H3PW) supported on silica-alumina. Impregnation of H3PW (15, 20, 30 and 40 wt.%) on commercial silica-alumina support in acidic aqueous solution is effective for preparing this catalyst keeping its Keggin structure, according to different methods of characterization. The catalysts were tested in a model reaction of acetic acid with ethanol and 30 wt.% H3PW/SiO2-Al2O3 had the highest activity under the conditions: catalyst calcination at 300 ºC, temperature of 100 ºC, acetic acid:ethanol molar ratio of 2:1 and catalyst:acetic acid mass ratio of 10 wt.%. The reaction yield was 79 and 100% selectivity for ethyl acetate over three reutilizations, for reaction time of 2 h. The calculated total acid site distribution was 0.299 mmol g-1 (97% of the theoretical probed by pyridine), and most of these (0.236 mmol g-1) were Brønsted weak-medium strength (pyridine desorption between 300 and 500 ºC). |
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Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-aluminaSílica-aluminaÁlcoolEsterificaçãoThis work deals with preparation and characterization of H3PW12O40 (H3PW) supported on silica-alumina. Impregnation of H3PW (15, 20, 30 and 40 wt.%) on commercial silica-alumina support in acidic aqueous solution is effective for preparing this catalyst keeping its Keggin structure, according to different methods of characterization. The catalysts were tested in a model reaction of acetic acid with ethanol and 30 wt.% H3PW/SiO2-Al2O3 had the highest activity under the conditions: catalyst calcination at 300 ºC, temperature of 100 ºC, acetic acid:ethanol molar ratio of 2:1 and catalyst:acetic acid mass ratio of 10 wt.%. The reaction yield was 79 and 100% selectivity for ethyl acetate over three reutilizations, for reaction time of 2 h. The calculated total acid site distribution was 0.299 mmol g-1 (97% of the theoretical probed by pyridine), and most of these (0.236 mmol g-1) were Brønsted weak-medium strength (pyridine desorption between 300 and 500 ºC).Instituto de Química (IQ)Sociedade Brasileira de Química2018-01-04T19:14:42Z2018-01-04T19:14:42Z2017-02info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfMATTOS, Flávia C. G. de et al. Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina. Journal of the Brazilian Chemical Society, São Paulo, v. 28, n. 2, p. 336-347, fev. 2017. Disponível em: <http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532017000200336&lng=en&nrm=iso>. Acesso em: 7 fev. 2018. doi: http://dx.doi.org/10.5935/0103-5053.20160183.http://repositorio.unb.br/handle/10482/30690http://dx.doi.org/10.5935/0103-5053.20160183Journal of the Brazilian Chemical Society - This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0). Fonte: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532017000200336&lng=en&nrm=iso. Acesso em: 7 fev. 2018.info:eu-repo/semantics/openAccessMattos, Flávia Cardoso Genaro deCarvalho, Eduardo N. C. B. deFreitas, Elon F. dePaiva, Mateus F.Ghesti, Grace FerreiraMacedo, Julio Lemos deDias, Sílvia Cláudia LoureiroDias, José Alvesengreponame:Repositório Institucional da UnBinstname:Universidade de Brasília (UnB)instacron:UNB2023-09-15T10:44:28Zoai:repositorio.unb.br:10482/30690Repositório InstitucionalPUBhttps://repositorio.unb.br/oai/requestrepositorio@unb.bropendoar:2023-09-15T10:44:28Repositório Institucional da UnB - Universidade de Brasília (UnB)false |
dc.title.none.fl_str_mv |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
title |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
spellingShingle |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina Mattos, Flávia Cardoso Genaro de Sílica-alumina Álcool Esterificação |
title_short |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
title_full |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
title_fullStr |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
title_full_unstemmed |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
title_sort |
Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina |
author |
Mattos, Flávia Cardoso Genaro de |
author_facet |
Mattos, Flávia Cardoso Genaro de Carvalho, Eduardo N. C. B. de Freitas, Elon F. de Paiva, Mateus F. Ghesti, Grace Ferreira Macedo, Julio Lemos de Dias, Sílvia Cláudia Loureiro Dias, José Alves |
author_role |
author |
author2 |
Carvalho, Eduardo N. C. B. de Freitas, Elon F. de Paiva, Mateus F. Ghesti, Grace Ferreira Macedo, Julio Lemos de Dias, Sílvia Cláudia Loureiro Dias, José Alves |
author2_role |
author author author author author author author |
dc.contributor.author.fl_str_mv |
Mattos, Flávia Cardoso Genaro de Carvalho, Eduardo N. C. B. de Freitas, Elon F. de Paiva, Mateus F. Ghesti, Grace Ferreira Macedo, Julio Lemos de Dias, Sílvia Cláudia Loureiro Dias, José Alves |
dc.subject.por.fl_str_mv |
Sílica-alumina Álcool Esterificação |
topic |
Sílica-alumina Álcool Esterificação |
description |
This work deals with preparation and characterization of H3PW12O40 (H3PW) supported on silica-alumina. Impregnation of H3PW (15, 20, 30 and 40 wt.%) on commercial silica-alumina support in acidic aqueous solution is effective for preparing this catalyst keeping its Keggin structure, according to different methods of characterization. The catalysts were tested in a model reaction of acetic acid with ethanol and 30 wt.% H3PW/SiO2-Al2O3 had the highest activity under the conditions: catalyst calcination at 300 ºC, temperature of 100 ºC, acetic acid:ethanol molar ratio of 2:1 and catalyst:acetic acid mass ratio of 10 wt.%. The reaction yield was 79 and 100% selectivity for ethyl acetate over three reutilizations, for reaction time of 2 h. The calculated total acid site distribution was 0.299 mmol g-1 (97% of the theoretical probed by pyridine), and most of these (0.236 mmol g-1) were Brønsted weak-medium strength (pyridine desorption between 300 and 500 ºC). |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-02 2018-01-04T19:14:42Z 2018-01-04T19:14:42Z |
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 |
MATTOS, Flávia C. G. de et al. Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina. Journal of the Brazilian Chemical Society, São Paulo, v. 28, n. 2, p. 336-347, fev. 2017. Disponível em: <http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532017000200336&lng=en&nrm=iso>. Acesso em: 7 fev. 2018. doi: http://dx.doi.org/10.5935/0103-5053.20160183. http://repositorio.unb.br/handle/10482/30690 http://dx.doi.org/10.5935/0103-5053.20160183 |
identifier_str_mv |
MATTOS, Flávia C. G. de et al. Acidity and characterization of 12-Tungstophosphoric acid supported on Silica-alumina. Journal of the Brazilian Chemical Society, São Paulo, v. 28, n. 2, p. 336-347, fev. 2017. Disponível em: <http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532017000200336&lng=en&nrm=iso>. Acesso em: 7 fev. 2018. doi: http://dx.doi.org/10.5935/0103-5053.20160183. |
url |
http://repositorio.unb.br/handle/10482/30690 http://dx.doi.org/10.5935/0103-5053.20160183 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
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 |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UnB instname:Universidade de Brasília (UnB) instacron:UNB |
instname_str |
Universidade de Brasília (UnB) |
instacron_str |
UNB |
institution |
UNB |
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Repositório Institucional da UnB |
collection |
Repositório Institucional da UnB |
repository.name.fl_str_mv |
Repositório Institucional da UnB - Universidade de Brasília (UnB) |
repository.mail.fl_str_mv |
repositorio@unb.br |
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1810580883775684608 |