Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts

Detalhes bibliográficos
Autor(a) principal: Braga, Valdeilson Souza
Data de Publicação: 2008
Outros Autores: Barros, Ivoneide de Carvalho Lopes, Garcia, Fillipe Augusto da Costa, Dias, Sílvia Cláudia Loureiro, Dias, José Alves
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UFBA
Texto Completo: http://www.repositorio.ufba.br/ri/handle/ri/6310
Resumo: Acesso restrito: Texto completo. p. 106-112.
id UFBA-2_4b9068a06d48ed5484d0b84e2cc43a60
oai_identifier_str oai:repositorio.ufba.br:ri/6310
network_acronym_str UFBA-2
network_name_str Repositório Institucional da UFBA
repository_id_str 1932
spelling Braga, Valdeilson SouzaBarros, Ivoneide de Carvalho LopesGarcia, Fillipe Augusto da CostaDias, Sílvia Cláudia LoureiroDias, José AlvesBraga, Valdeilson SouzaBarros, Ivoneide de Carvalho LopesGarcia, Fillipe Augusto da CostaDias, Sílvia Cláudia LoureiroDias, José Alves2012-07-04T14:41:54Z20080920-5861http://www.repositorio.ufba.br/ri/handle/ri/6310v. 133Acesso restrito: Texto completo. p. 106-112.Supported niobium pentoxide catalysts are active for a variety of acid and redox catalyzed reactions such as dehydration, hydrogenation and esterification. In this work, niobium pentoxide has been supported on silica–alumina using two methods: grafting in CH2Cl2 or ethanol solution with NbCl5 precursor, and impregnating in aqueous solution with ammonium niobium oxalate. XRD, TG/DTG/DTA, FTIR, DRIFTS, FT-Raman,and calorimetric titration with pyridine were used to characterize the materials. Calcination of the materials at 800 8C produced crystalline Nb2O5 (T-phase) for the samples prepared by grafting, while a mixture of T- and H-phases are formed by aqueous impregnation, indicating the higher stability of the former materials. Thermal analysis confirmed a stronger interaction of niobium oxide species on the silica–alumina surface for the grafting procedure. On the other hand, partial neutralization of hydroxyl groups occurred on the support surface by grafting process, and the neutralization reaction is practically complete at 25 wt.% of Nb2O5 by impregnation. The catalysts with about 10 wt.% of Nb2O5 prepared by aqueous impregnation reached the monolayer, while by grafting it predominates bulk Nb2O5, as demonstrated by FT-Raman. These catalysts also showed the highest acidity, when calcined at 300 8C. Based on these results, liquid phase esterification reactions of acetic acid were carried out with different alcohols (ethanol, n-butanol, and iso-pentanol). The yields were about the same, independent of the preparation method for 10 wt.% Nb2O5 catalysts. The conversions using molar ratio 2:1 (acid:alcohol) after 8 h showed good results (83, 87, and 91%, respectively) and 100% selectivity for all esters.Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-07-04T14:41:54Z No. of bitstreams: 1 CONFIG~1....0-S0920586107008656-main.pdf: 276187 bytes, checksum: ddb0bdb40f6779c31e33903714a91483 (MD5)Made available in DSpace on 2012-07-04T14:41:54Z (GMT). No. of bitstreams: 1 CONFIG~1....0-S0920586107008656-main.pdf: 276187 bytes, checksum: ddb0bdb40f6779c31e33903714a91483 (MD5) Previous issue date: 2008http://dx.doi.org/10.1016/j.cattod.2007.12.091reponame:Repositório Institucional da UFBAinstname:Universidade Federal da Bahia (UFBA)instacron:UFBAEsterificationNiobium pentoxideSilica–aluminaSupported catalystSolid acidEsterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalystsCatalysis Todayinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article10000-01-01enginfo:eu-repo/semantics/openAccessORIGINALCONFIG~1....0-S0920586107008656-main.pdfCONFIG~1....0-S0920586107008656-main.pdfapplication/pdf276187https://repositorio.ufba.br/bitstream/ri/6310/1/CONFIG~1....0-S0920586107008656-main.pdfddb0bdb40f6779c31e33903714a91483MD51LICENSElicense.txtlicense.txttext/plain1762https://repositorio.ufba.br/bitstream/ri/6310/2/license.txt1b89a9a0548218172d7c829f87a0eab9MD52TEXTCONFIG~1....0-S0920586107008656-main.pdf.txtCONFIG~1....0-S0920586107008656-main.pdf.txtExtracted texttext/plain31391https://repositorio.ufba.br/bitstream/ri/6310/3/CONFIG~1....0-S0920586107008656-main.pdf.txt04bb7be24b5c0e6d618e7b269fa4e6e4MD53ri/63102022-07-05 14:03:10.624oai:repositorio.ufba.br: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Repositório InstitucionalPUBhttp://192.188.11.11:8080/oai/requestopendoar:19322022-07-05T17:03:10Repositório Institucional da UFBA - Universidade Federal da Bahia (UFBA)false
dc.title.pt_BR.fl_str_mv Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
dc.title.alternative.pt_BR.fl_str_mv Catalysis Today
title Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
spellingShingle Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
Braga, Valdeilson Souza
Esterification
Niobium pentoxide
Silica–alumina
Supported catalyst
Solid acid
title_short Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
title_full Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
title_fullStr Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
title_full_unstemmed Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
title_sort Esterification of acetic acid with alcohols using supported niobium pentoxide on silica–alumina catalysts
author Braga, Valdeilson Souza
author_facet Braga, Valdeilson Souza
Barros, Ivoneide de Carvalho Lopes
Garcia, Fillipe Augusto da Costa
Dias, Sílvia Cláudia Loureiro
Dias, José Alves
author_role author
author2 Barros, Ivoneide de Carvalho Lopes
Garcia, Fillipe Augusto da Costa
Dias, Sílvia Cláudia Loureiro
Dias, José Alves
author2_role author
author
author
author
dc.contributor.author.fl_str_mv Braga, Valdeilson Souza
Barros, Ivoneide de Carvalho Lopes
Garcia, Fillipe Augusto da Costa
Dias, Sílvia Cláudia Loureiro
Dias, José Alves
Braga, Valdeilson Souza
Barros, Ivoneide de Carvalho Lopes
Garcia, Fillipe Augusto da Costa
Dias, Sílvia Cláudia Loureiro
Dias, José Alves
dc.subject.por.fl_str_mv Esterification
Niobium pentoxide
Silica–alumina
Supported catalyst
Solid acid
topic Esterification
Niobium pentoxide
Silica–alumina
Supported catalyst
Solid acid
description Acesso restrito: Texto completo. p. 106-112.
publishDate 2008
dc.date.issued.fl_str_mv 2008
dc.date.accessioned.fl_str_mv 2012-07-04T14:41:54Z
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://www.repositorio.ufba.br/ri/handle/ri/6310
dc.identifier.issn.none.fl_str_mv 0920-5861
dc.identifier.number.pt_BR.fl_str_mv v. 133
identifier_str_mv 0920-5861
v. 133
url http://www.repositorio.ufba.br/ri/handle/ri/6310
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.source.pt_BR.fl_str_mv http://dx.doi.org/10.1016/j.cattod.2007.12.091
dc.source.none.fl_str_mv reponame:Repositório Institucional da UFBA
instname:Universidade Federal da Bahia (UFBA)
instacron:UFBA
instname_str Universidade Federal da Bahia (UFBA)
instacron_str UFBA
institution UFBA
reponame_str Repositório Institucional da UFBA
collection Repositório Institucional da UFBA
bitstream.url.fl_str_mv https://repositorio.ufba.br/bitstream/ri/6310/1/CONFIG~1....0-S0920586107008656-main.pdf
https://repositorio.ufba.br/bitstream/ri/6310/2/license.txt
https://repositorio.ufba.br/bitstream/ri/6310/3/CONFIG~1....0-S0920586107008656-main.pdf.txt
bitstream.checksum.fl_str_mv ddb0bdb40f6779c31e33903714a91483
1b89a9a0548218172d7c829f87a0eab9
04bb7be24b5c0e6d618e7b269fa4e6e4
bitstream.checksumAlgorithm.fl_str_mv MD5
MD5
MD5
repository.name.fl_str_mv Repositório Institucional da UFBA - Universidade Federal da Bahia (UFBA)
repository.mail.fl_str_mv
_version_ 1801502448845586432

Registros relacionados