Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais
Autor(a) principal: | |
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Data de Publicação: | 2014 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFSCAR |
Texto Completo: | https://repositorio.ufscar.br/handle/ufscar/4150 |
Resumo: | Acetic acid (AA), one majority substance contained in the bio-oil from biomass pyrolysis, was used as a model molecule for study of reaction routes of steam reforming on Ni/θ-Al2O3 catalysts. The catalyst containing 15% nickel (w/w), prepared by wet impregnation in a θ-Al2O3. The samples were characterized: nitrogen adsorption, ammonia desorption, X-ray diffraction, temperature programmed reduction and thermogravimetric analysis. The reaction routes were studied using: a) temperature programmed desorption (TPD), b) temperature programmed decomposition e c) temperature programmed steam reforming (TPSR) with ratios of 3:1, 6:1 or 9:1 of H2O: AA. The results of TPD where AA was adsorbed and decomposed in function of temperature, show simultaneous desorption of CO, CO2, H2 and CH4 which is explained by the formation of acetic anhydride on the surface of Ni which decomposes into CH3COO* and/or CH3CO* and then CO, CO2 and H2. The TPSR results suggest that the reaction route of decomposition and reform of AA depend on the temperature and the ratio H2O:AA. At low temperatures (< 650 K) and low ratios H2O:AA has the formation of CO and CO2 via bond breaking C-C of species CH3COO* and CH3CO* formed from acetic anhydride. With increasing temperature the anhydride formation is disfavored, in region between 600-800 K, there is interaction and dimerization of AA molecule adsorbed on Ni, which leads to the formation of C2H4. At the same time to this reaction, the formation of CH4 is verified by the hydrogenation CH3* species formed by breaking of CH3COO* and/or CH3CO* species. In high temperatures (> 800 K) methane formation is favored, possibly by decomposition of species CH3 in C* e H2, C* is oxidized by water. In highest ratio (9:1), the formation of the anhydride is not favored and the reforming reactions occur via decomposition of CH3COO* species. In low temperature, formation of CH4 is not observed and the oxidation of CH3* species may occur via the formation of formates. With increasing temperature oxidation of these CH3* radicals via pyrolytic should be favored. |
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Burak, Jorge Augusto MendesBueno, José Maria Corrêahttp://lattes.cnpq.br/0157452280626031http://lattes.cnpq.br/31892695948932394eeac4e9-0f17-439a-a9a0-7387a3069cb12016-06-02T19:56:56Z2014-09-302016-06-02T19:56:56Z2014-02-21BURAK, Jorge Augusto Mendes. Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: Estudo das rotas reacionais. 2014. 64 f. Dissertação (Mestrado em Ciências Exatas e da Terra) - Universidade Federal de São Carlos, São Carlos, 2014.https://repositorio.ufscar.br/handle/ufscar/4150Acetic acid (AA), one majority substance contained in the bio-oil from biomass pyrolysis, was used as a model molecule for study of reaction routes of steam reforming on Ni/θ-Al2O3 catalysts. The catalyst containing 15% nickel (w/w), prepared by wet impregnation in a θ-Al2O3. The samples were characterized: nitrogen adsorption, ammonia desorption, X-ray diffraction, temperature programmed reduction and thermogravimetric analysis. The reaction routes were studied using: a) temperature programmed desorption (TPD), b) temperature programmed decomposition e c) temperature programmed steam reforming (TPSR) with ratios of 3:1, 6:1 or 9:1 of H2O: AA. The results of TPD where AA was adsorbed and decomposed in function of temperature, show simultaneous desorption of CO, CO2, H2 and CH4 which is explained by the formation of acetic anhydride on the surface of Ni which decomposes into CH3COO* and/or CH3CO* and then CO, CO2 and H2. The TPSR results suggest that the reaction route of decomposition and reform of AA depend on the temperature and the ratio H2O:AA. At low temperatures (< 650 K) and low ratios H2O:AA has the formation of CO and CO2 via bond breaking C-C of species CH3COO* and CH3CO* formed from acetic anhydride. With increasing temperature the anhydride formation is disfavored, in region between 600-800 K, there is interaction and dimerization of AA molecule adsorbed on Ni, which leads to the formation of C2H4. At the same time to this reaction, the formation of CH4 is verified by the hydrogenation CH3* species formed by breaking of CH3COO* and/or CH3CO* species. In high temperatures (> 800 K) methane formation is favored, possibly by decomposition of species CH3 in C* e H2, C* is oxidized by water. In highest ratio (9:1), the formation of the anhydride is not favored and the reforming reactions occur via decomposition of CH3COO* species. In low temperature, formation of CH4 is not observed and the oxidation of CH3* species may occur via the formation of formates. With increasing temperature oxidation of these CH3* radicals via pyrolytic should be favored.O ácido acético (AA), uma das principais substâncias contidas no bio-óleo proveniente de pirólise de biomassa, foi utilizado como molécula modelo no estudo das rotas de reação da reforma a vapor sobre catalisadores de Ni/θ-Al2O3. O catalisador, contendo 15 % em massa de níquel, foi preparado por impregnação úmida utilizando-se uma θ-Al2O3. As amostras foram caracterizadas por fisissorção de nitrogênio, dessorção de amônia, difração de raios-x, redução a temperatura programa e análise termogravimétrica. As rotas reacionais foram estudadas utilizando-se: a) dessorção a temperatura programa de AA (TPD), b) decomposição do AA e c) reações de reforma a vapor do AA (TPSR), com razões molares de H2O: AA de 3:1, 6:1 ou 9:1. Os resultados de TPD, onde o AA foi adsorvido e decomposto em função da temperatura, mostra a dessorção simultânea de CO, CO2, H2 e CH4 que é explicada através da formação de anidrido acético sobre a superfície do Ni o qual se decompõe em CH3COO* e/ou CH3CO* e em seguida CO, CO2 e H2. Os resultados de TPSR sugerem que as rota reacionais para decomposição e reforma do AA dependem da temperatura e da razão H2O:AA. Em baixa temperatura (< 650 K) e baixas razões H2O: AA tem-se a formação de CO e CO2 via quebra da ligação C-C das espécies CH3COO* e CH3CO* formadas a partir do anidrido acético. Com o aumento da temperatura a formação de anidrido é desfavorecida e em temperaturas na região entre 600-800 K, tem-se a interação e dimerização da molécula AA adsorvido sobre o Ni, que leva a formação de C2H4. Em paralelo a esta reação verifica-se a formação de CH4 através da hidrogenação das espécies CH3* formados por quebra das espécies CH3COO* e/ou CH3CO*. Em altas temperaturas (> 800 K) a formação de metano é desfavorecida, possivelmente pela decomposição dos espécies CH3 em C* e H2, sendo C* oxidado pela água. Já em alta razão (9:1), a formação do anidrido não é favorecida e a reação de reforma ocorre via decomposição de espécies CH3COO*. Em baixa temperatura a formação de CH4 não é observada e a oxidação das espécies CH3* podem ocorrer via a formação de formiatos. Com o aumento de temperatura a oxidação desses radicais CH3* via pirolítica deve ser favorecida.Financiadora de Estudos e Projetosapplication/pdfporUniversidade Federal de São CarlosPrograma de Pós-Graduação em Engenharia Química - PPGEQUFSCarBRCatáliseÁcido acéticoNíquelReforma à vaporRotas reacionaisAcetic acidReactions rotesNickelSteam reformingENGENHARIAS::ENGENHARIA QUIMICAReforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionaisinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesis-1-13b275236-acc5-4218-a33b-8f802e7f5a18info:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFSCARinstname:Universidade Federal de São Carlos (UFSCAR)instacron:UFSCARORIGINAL6201.pdfapplication/pdf1691871https://repositorio.ufscar.br/bitstream/ufscar/4150/1/6201.pdf6c83b1bac5cb0a7669949d88fb279a1bMD51TEXT6201.pdf.txt6201.pdf.txtExtracted texttext/plain0https://repositorio.ufscar.br/bitstream/ufscar/4150/2/6201.pdf.txtd41d8cd98f00b204e9800998ecf8427eMD52THUMBNAIL6201.pdf.jpg6201.pdf.jpgIM Thumbnailimage/jpeg6627https://repositorio.ufscar.br/bitstream/ufscar/4150/3/6201.pdf.jpg6032b95989a1f6f0e2aab39716b9859bMD53ufscar/41502023-09-18 18:31:34.409oai:repositorio.ufscar.br:ufscar/4150Repositório InstitucionalPUBhttps://repositorio.ufscar.br/oai/requestopendoar:43222023-09-18T18:31:34Repositório Institucional da UFSCAR - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.por.fl_str_mv |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
title |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
spellingShingle |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais Burak, Jorge Augusto Mendes Catálise Ácido acético Níquel Reforma à vapor Rotas reacionais Acetic acid Reactions rotes Nickel Steam reforming ENGENHARIAS::ENGENHARIA QUIMICA |
title_short |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
title_full |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
title_fullStr |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
title_full_unstemmed |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
title_sort |
Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: estudo das rotas reacionais |
author |
Burak, Jorge Augusto Mendes |
author_facet |
Burak, Jorge Augusto Mendes |
author_role |
author |
dc.contributor.authorlattes.por.fl_str_mv |
http://lattes.cnpq.br/3189269594893239 |
dc.contributor.author.fl_str_mv |
Burak, Jorge Augusto Mendes |
dc.contributor.advisor1.fl_str_mv |
Bueno, José Maria Corrêa |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/0157452280626031 |
dc.contributor.authorID.fl_str_mv |
4eeac4e9-0f17-439a-a9a0-7387a3069cb1 |
contributor_str_mv |
Bueno, José Maria Corrêa |
dc.subject.por.fl_str_mv |
Catálise Ácido acético Níquel Reforma à vapor Rotas reacionais |
topic |
Catálise Ácido acético Níquel Reforma à vapor Rotas reacionais Acetic acid Reactions rotes Nickel Steam reforming ENGENHARIAS::ENGENHARIA QUIMICA |
dc.subject.eng.fl_str_mv |
Acetic acid Reactions rotes Nickel Steam reforming |
dc.subject.cnpq.fl_str_mv |
ENGENHARIAS::ENGENHARIA QUIMICA |
description |
Acetic acid (AA), one majority substance contained in the bio-oil from biomass pyrolysis, was used as a model molecule for study of reaction routes of steam reforming on Ni/θ-Al2O3 catalysts. The catalyst containing 15% nickel (w/w), prepared by wet impregnation in a θ-Al2O3. The samples were characterized: nitrogen adsorption, ammonia desorption, X-ray diffraction, temperature programmed reduction and thermogravimetric analysis. The reaction routes were studied using: a) temperature programmed desorption (TPD), b) temperature programmed decomposition e c) temperature programmed steam reforming (TPSR) with ratios of 3:1, 6:1 or 9:1 of H2O: AA. The results of TPD where AA was adsorbed and decomposed in function of temperature, show simultaneous desorption of CO, CO2, H2 and CH4 which is explained by the formation of acetic anhydride on the surface of Ni which decomposes into CH3COO* and/or CH3CO* and then CO, CO2 and H2. The TPSR results suggest that the reaction route of decomposition and reform of AA depend on the temperature and the ratio H2O:AA. At low temperatures (< 650 K) and low ratios H2O:AA has the formation of CO and CO2 via bond breaking C-C of species CH3COO* and CH3CO* formed from acetic anhydride. With increasing temperature the anhydride formation is disfavored, in region between 600-800 K, there is interaction and dimerization of AA molecule adsorbed on Ni, which leads to the formation of C2H4. At the same time to this reaction, the formation of CH4 is verified by the hydrogenation CH3* species formed by breaking of CH3COO* and/or CH3CO* species. In high temperatures (> 800 K) methane formation is favored, possibly by decomposition of species CH3 in C* e H2, C* is oxidized by water. In highest ratio (9:1), the formation of the anhydride is not favored and the reforming reactions occur via decomposition of CH3COO* species. In low temperature, formation of CH4 is not observed and the oxidation of CH3* species may occur via the formation of formates. With increasing temperature oxidation of these CH3* radicals via pyrolytic should be favored. |
publishDate |
2014 |
dc.date.available.fl_str_mv |
2014-09-30 2016-06-02T19:56:56Z |
dc.date.issued.fl_str_mv |
2014-02-21 |
dc.date.accessioned.fl_str_mv |
2016-06-02T19:56:56Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
BURAK, Jorge Augusto Mendes. Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: Estudo das rotas reacionais. 2014. 64 f. Dissertação (Mestrado em Ciências Exatas e da Terra) - Universidade Federal de São Carlos, São Carlos, 2014. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufscar.br/handle/ufscar/4150 |
identifier_str_mv |
BURAK, Jorge Augusto Mendes. Reforma a vapor do ácido acético sobre catalisadores de Ni/Al2O3: Estudo das rotas reacionais. 2014. 64 f. Dissertação (Mestrado em Ciências Exatas e da Terra) - Universidade Federal de São Carlos, São Carlos, 2014. |
url |
https://repositorio.ufscar.br/handle/ufscar/4150 |
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por |
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Universidade Federal de São Carlos |
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Programa de Pós-Graduação em Engenharia Química - PPGEQ |
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UFSCar |
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BR |
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Universidade Federal de São Carlos |
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