Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo
Ano de defesa: | 2021 |
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Autor(a) principal: | |
Outros Autores: | |
Orientador(a): | , |
Banca de defesa: | , , |
Tipo de documento: | Dissertação |
Tipo de acesso: | Acesso aberto |
Idioma: | por |
Instituição de defesa: |
Universidade do Estado do Rio de Janeiro
|
Programa de Pós-Graduação: |
Programa de Pós-Graduação em Engenharia Química
|
Departamento: |
Centro de Tecnologia e Ciências::Instituto de Química
|
País: |
Brasil
|
Palavras-chave em Português: | |
Palavras-chave em Inglês: | |
Área do conhecimento CNPq: | |
Link de acesso: | http://www.bdtd.uerj.br/handle/1/17712 |
Resumo: | In the last decades, several studies have been developed owing to fuels production from renewable sources. Among the most studied biofuels appears bio-oil, a mixture of organic compounds rich in oxygenates. After being produced, crude bio-oil cannot be used as a fuel for some reasons, among which can be highlighted its high acidity due to the presence of carboxylic acids. So, it is necessary to carry out beneficiation processes to fit bio-oil as a fuel, such as, the esterification of carboxylic acids with alcohols over acid catalysts, which results in esters production and acidity reduction. The replacement of the usual liquid acid catalyst with solid ones is environmentally and economically favorable. In this work, solid acid catalysts based on niobium were synthesized for esterification of acetic acid aiming at bio-oil upgrading. Sulphated and phosphated niobias were synthesized by treating hydrated niobium oxide with different sulfuric acid and phosphoric acid solutions (0.5, 1 and 2 M). The ratio between solid and solution was also varied (20: 300 and 20: 500) and the treatment time was maintained at 1h. After treatment, the suspension was filtered and the solid dried and calcined at 500 oC. Therefore, 12 catalysts were obtained, 6 of them were sulphated and 6 were phosphated, besides niobium phosphate and niobium oxide calcined at the same condition. The catalytic activities of these samples were evaluated in the model reaction of esterification of acetic acid with ethanol, at 60 °C and 1 atm. The materials were also characterized by the following techniques: X-ray diffraction; Infrared absorption spectroscopy of samples diluted in KBr and also adsorbed in pyridine; Thermoprogrammed desorption (TPD) of adsorbed ammonia, Textural analysis with N2 physisorption and Elementary analysis. By elementary analysis, it was possible to confirm the sulphate and phosphate ions incorporation into niobium oxide. From TPD, it was possible to observe the increase in the surface acidity of the solids after the treatment of niobium oxide, due to the higher amount of NH3 adsorption. After the treatment, all catalysts achieved higher surface areas and smaller volumes and pore diameters compared to niobium oxide. From XRD technique, it was observed that all sulphated solids are less crystalline than pure niobium oxide, and in phosphate ones the treatment caused amorphization. The FTIR confirmed the presence of S=O and P=O species on the treated samples. DRIFTS identified the presence of Lewis and Brönsted acid sites. The sulphated and phosphated catalysts obtained in the 2 M concentration and 20:300 ratio as well as bulk niobium oxide and niobium phosphate were all tested for reuse. Niobium oxide and niobium phosphate showed similar activities to those of the respective fresh catalysts, even after the third use. However, functionalized niobias showed severe decrease in activity. |
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Paredes, Márcio Luis Lyrahttp://lattes.cnpq.br/3351408490818921Araujo , Lucia Regina Raddi dehttp://lattes.cnpq.br/1592062469734844Zotin, Fátima Maria Zanonhttp://lattes.cnpq.br/2398224913573093Lachter, Elizabeth Roditihttp://lattes.cnpq.br/8688736650901616Gonzalez, Wilma de Araújohttp://lattes.cnpq.br/0940920635144544http://lattes.cnpq.br/7399677352201760Costa, Gustavo Carvalho dagustccosta@gmail.com2022-05-10T15:34:20Z2021-06-08COSTA, Gustavo Carvalho da. Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo. 2021. 117 f. Dissertação (Mestrado em Engenharia Química) - Faculdade de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2021.http://www.bdtd.uerj.br/handle/1/17712In the last decades, several studies have been developed owing to fuels production from renewable sources. Among the most studied biofuels appears bio-oil, a mixture of organic compounds rich in oxygenates. After being produced, crude bio-oil cannot be used as a fuel for some reasons, among which can be highlighted its high acidity due to the presence of carboxylic acids. So, it is necessary to carry out beneficiation processes to fit bio-oil as a fuel, such as, the esterification of carboxylic acids with alcohols over acid catalysts, which results in esters production and acidity reduction. The replacement of the usual liquid acid catalyst with solid ones is environmentally and economically favorable. In this work, solid acid catalysts based on niobium were synthesized for esterification of acetic acid aiming at bio-oil upgrading. Sulphated and phosphated niobias were synthesized by treating hydrated niobium oxide with different sulfuric acid and phosphoric acid solutions (0.5, 1 and 2 M). The ratio between solid and solution was also varied (20: 300 and 20: 500) and the treatment time was maintained at 1h. After treatment, the suspension was filtered and the solid dried and calcined at 500 oC. Therefore, 12 catalysts were obtained, 6 of them were sulphated and 6 were phosphated, besides niobium phosphate and niobium oxide calcined at the same condition. The catalytic activities of these samples were evaluated in the model reaction of esterification of acetic acid with ethanol, at 60 °C and 1 atm. The materials were also characterized by the following techniques: X-ray diffraction; Infrared absorption spectroscopy of samples diluted in KBr and also adsorbed in pyridine; Thermoprogrammed desorption (TPD) of adsorbed ammonia, Textural analysis with N2 physisorption and Elementary analysis. By elementary analysis, it was possible to confirm the sulphate and phosphate ions incorporation into niobium oxide. From TPD, it was possible to observe the increase in the surface acidity of the solids after the treatment of niobium oxide, due to the higher amount of NH3 adsorption. After the treatment, all catalysts achieved higher surface areas and smaller volumes and pore diameters compared to niobium oxide. From XRD technique, it was observed that all sulphated solids are less crystalline than pure niobium oxide, and in phosphate ones the treatment caused amorphization. The FTIR confirmed the presence of S=O and P=O species on the treated samples. DRIFTS identified the presence of Lewis and Brönsted acid sites. The sulphated and phosphated catalysts obtained in the 2 M concentration and 20:300 ratio as well as bulk niobium oxide and niobium phosphate were all tested for reuse. Niobium oxide and niobium phosphate showed similar activities to those of the respective fresh catalysts, even after the third use. However, functionalized niobias showed severe decrease in activity.Nas últimas décadas, vários estudos têm se desenvolvido visando à produção de combustíveis a partir de fontes renováveis. Dentre os biocombustíveis mais estudados aparece o bio-óleo, uma mistura de compostos orgânicos rica em oxigenados. O bio-óleo cru não pode ser utilizado como combustível por alguns motivos, como a sua elevada acidez proveniente da presença de ácidos carboxílicos. Para enquadramento do bio-óleo como combustível é necessária a realização de processos de beneficiamento, como por exemplo, a esterificação de ácidos carboxílicos com álcoois sobre catalisadores ácidos, com geração de ésteres, resultando na redução de sua acidez. O uso de catalisadores sólidos em substituição aos usuais ácidos minerais líquidos é ambiental e economicamente favorável. Neste trabalho, foram preparados catalisadores sólidos ácidos a base de nióbio para esterificação de ácido acético visando o beneficiamento de bio-óleo. Nióbias sulfatadas e fosfatadas foram sintetizadas por tratamento do óxido de nióbio hidratado com soluções aquosas de ácido sulfúrico e ácido fosfórico com diferentes concentrações (0,5; 1 e 2 M). Também se variou a proporção entre sólido e solução (20:300 e 20:500) e o tempo de tratamento foi mantido em 1 h. Após o tratamento, a suspensão foi filtrada e o sólido seco e calcinado a 500 °C, obtendo-se 12 catalisadores, 6 sulfatados e 6 fostatados, além do fosfato de nióbio e da nióbia, calcinados na mesma condição. Os catalisadores foram avaliados quanto à atividade catalítica na reação modelo de esterificação do ácido acético com etanol, a 60 °C e 1 atm, e caracterizados pelas seguintes técnicas: Difração de raios-X; Espectroscopia de absorção no infravermelho de amostras diluídas em KBr e com piridina adsorvida; Dessorção termoprogramada (TPD) de amônia adsorvida, Análise textural com Fisissorção de N2 e Análise elementar. Pela análise elementar, foi possível verificar que os íons sulfato e fosfato foram incorporados na nióbia. Pela TPD foi possível observar o aumento da acidez superficial dos sólidos após o tratamento do óxido de nióbio, devido à maior adsorção de NH3. Com o tratamento, todos os catalisadores apresentaram maior área e menor volume e diâmetros de poros em relação à nióbia. Pelo DRX foi observado que todas as amostras sulfatadas são menos cristalinas que a nióbia pura, e nas amostras fosfatadas o tratamento causou amorfização. Com o FTIR foi confirmada a presença de espécies S=O e P=O nas amostras tratadas. Pelo DRIFTS foi verificada a presença de sítios ácidos de Lewis e de Brönsted. Os catalisadores sulfatados e fosfatados obtidos na concentração 2 M e proporção 20:300 foram testados quanto ao reuso, além da nióbia e do fosfato mássicos. A nióbia e o fosfato de nióbio apresentaram atividades semelhantes às dos respectivos catalisadores virgens, mesmo após o terceiro uso. No entanto, as nióbias funcionalizadas apresentaram diminuição severa de atividade.Submitted by Ana Rachel CTC/Q (ana.teles@uerj.br) on 2022-05-10T15:34:20Z No. of bitstreams: 1 Dissertação - Gustavo Carvalho da Costa - 2021 - Completa.pdf: 6626497 bytes, checksum: 23fcc88903d6cfad4defa23f012dd776 (MD5)Made available in DSpace on 2022-05-10T15:34:20Z (GMT). No. of bitstreams: 1 Dissertação - Gustavo Carvalho da Costa - 2021 - Completa.pdf: 6626497 bytes, checksum: 23fcc88903d6cfad4defa23f012dd776 (MD5) Previous issue date: 2021-06-08Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESapplication/pdfporUniversidade do Estado do Rio de JaneiroPrograma de Pós-Graduação em Engenharia QuímicaUERJBrasilCentro de Tecnologia e Ciências::Instituto de QuímicaSynthesis of catalystsEsterificationNiobium oxideBio-oilSulphatingPhosphatingSíntese de catalisadoresEsterificaçãoNióbiaBio-óleoSulfataçãoFosfataçãoCatalizadoresBiocombustívelENGENHARIAS::ENGENHARIA QUIMICANióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleoSulphated and phosphated niobias as acid catalysts for esterification of acetic acid with ethanol aiming at bio-oil upgradinginfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisinfo:eu-repo/semantics/openAccessreponame:Biblioteca Digital de Teses e Dissertações da UERJinstname:Universidade do Estado do Rio de Janeiro (UERJ)instacron:UERJORIGINALDissertação - Gustavo Carvalho da Costa - 2021 - Completa.pdfDissertação - Gustavo Carvalho da Costa - 2021 - Completa.pdfapplication/pdf6626497http://www.bdtd.uerj.br/bitstream/1/17712/2/Disserta%C3%A7%C3%A3o+-+Gustavo+Carvalho+da+Costa+-+2021+-+Completa.pdf23fcc88903d6cfad4defa23f012dd776MD52LICENSElicense.txtlicense.txttext/plain; charset=utf-82123http://www.bdtd.uerj.br/bitstream/1/17712/1/license.txte5502652da718045d7fcd832b79fca29MD511/177122024-02-27 15:35:57.778oai:www.bdtd.uerj.br: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Biblioteca Digital de Teses e Dissertaçõeshttp://www.bdtd.uerj.br/PUBhttps://www.bdtd.uerj.br:8443/oai/requestbdtd.suporte@uerj.bropendoar:29032024-02-27T18:35:57Biblioteca Digital de Teses e Dissertações da UERJ - Universidade do Estado do Rio de Janeiro (UERJ)false |
dc.title.por.fl_str_mv |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
dc.title.alternative.eng.fl_str_mv |
Sulphated and phosphated niobias as acid catalysts for esterification of acetic acid with ethanol aiming at bio-oil upgrading |
title |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
spellingShingle |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo Costa, Gustavo Carvalho da Synthesis of catalysts Esterification Niobium oxide Bio-oil Sulphating Phosphating Síntese de catalisadores Esterificação Nióbia Bio-óleo Sulfatação Fosfatação Catalizadores Biocombustível ENGENHARIAS::ENGENHARIA QUIMICA |
title_short |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
title_full |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
title_fullStr |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
title_full_unstemmed |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
title_sort |
Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo |
author |
Costa, Gustavo Carvalho da |
author_facet |
Costa, Gustavo Carvalho da gustccosta@gmail.com |
author_role |
author |
author2 |
gustccosta@gmail.com |
author2_role |
author |
dc.contributor.advisor1.fl_str_mv |
Paredes, Márcio Luis Lyra |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/3351408490818921 |
dc.contributor.advisor2.fl_str_mv |
Araujo , Lucia Regina Raddi de |
dc.contributor.advisor2Lattes.fl_str_mv |
http://lattes.cnpq.br/1592062469734844 |
dc.contributor.referee1.fl_str_mv |
Zotin, Fátima Maria Zanon |
dc.contributor.referee1Lattes.fl_str_mv |
http://lattes.cnpq.br/2398224913573093 |
dc.contributor.referee2.fl_str_mv |
Lachter, Elizabeth Roditi |
dc.contributor.referee2Lattes.fl_str_mv |
http://lattes.cnpq.br/8688736650901616 |
dc.contributor.referee3.fl_str_mv |
Gonzalez, Wilma de Araújo |
dc.contributor.referee3Lattes.fl_str_mv |
http://lattes.cnpq.br/0940920635144544 |
dc.contributor.authorLattes.fl_str_mv |
http://lattes.cnpq.br/7399677352201760 |
dc.contributor.author.fl_str_mv |
Costa, Gustavo Carvalho da gustccosta@gmail.com |
contributor_str_mv |
Paredes, Márcio Luis Lyra Araujo , Lucia Regina Raddi de Zotin, Fátima Maria Zanon Lachter, Elizabeth Roditi Gonzalez, Wilma de Araújo |
dc.subject.eng.fl_str_mv |
Synthesis of catalysts Esterification Niobium oxide Bio-oil Sulphating Phosphating |
topic |
Synthesis of catalysts Esterification Niobium oxide Bio-oil Sulphating Phosphating Síntese de catalisadores Esterificação Nióbia Bio-óleo Sulfatação Fosfatação Catalizadores Biocombustível ENGENHARIAS::ENGENHARIA QUIMICA |
dc.subject.por.fl_str_mv |
Síntese de catalisadores Esterificação Nióbia Bio-óleo Sulfatação Fosfatação Catalizadores Biocombustível |
dc.subject.cnpq.fl_str_mv |
ENGENHARIAS::ENGENHARIA QUIMICA |
description |
In the last decades, several studies have been developed owing to fuels production from renewable sources. Among the most studied biofuels appears bio-oil, a mixture of organic compounds rich in oxygenates. After being produced, crude bio-oil cannot be used as a fuel for some reasons, among which can be highlighted its high acidity due to the presence of carboxylic acids. So, it is necessary to carry out beneficiation processes to fit bio-oil as a fuel, such as, the esterification of carboxylic acids with alcohols over acid catalysts, which results in esters production and acidity reduction. The replacement of the usual liquid acid catalyst with solid ones is environmentally and economically favorable. In this work, solid acid catalysts based on niobium were synthesized for esterification of acetic acid aiming at bio-oil upgrading. Sulphated and phosphated niobias were synthesized by treating hydrated niobium oxide with different sulfuric acid and phosphoric acid solutions (0.5, 1 and 2 M). The ratio between solid and solution was also varied (20: 300 and 20: 500) and the treatment time was maintained at 1h. After treatment, the suspension was filtered and the solid dried and calcined at 500 oC. Therefore, 12 catalysts were obtained, 6 of them were sulphated and 6 were phosphated, besides niobium phosphate and niobium oxide calcined at the same condition. The catalytic activities of these samples were evaluated in the model reaction of esterification of acetic acid with ethanol, at 60 °C and 1 atm. The materials were also characterized by the following techniques: X-ray diffraction; Infrared absorption spectroscopy of samples diluted in KBr and also adsorbed in pyridine; Thermoprogrammed desorption (TPD) of adsorbed ammonia, Textural analysis with N2 physisorption and Elementary analysis. By elementary analysis, it was possible to confirm the sulphate and phosphate ions incorporation into niobium oxide. From TPD, it was possible to observe the increase in the surface acidity of the solids after the treatment of niobium oxide, due to the higher amount of NH3 adsorption. After the treatment, all catalysts achieved higher surface areas and smaller volumes and pore diameters compared to niobium oxide. From XRD technique, it was observed that all sulphated solids are less crystalline than pure niobium oxide, and in phosphate ones the treatment caused amorphization. The FTIR confirmed the presence of S=O and P=O species on the treated samples. DRIFTS identified the presence of Lewis and Brönsted acid sites. The sulphated and phosphated catalysts obtained in the 2 M concentration and 20:300 ratio as well as bulk niobium oxide and niobium phosphate were all tested for reuse. Niobium oxide and niobium phosphate showed similar activities to those of the respective fresh catalysts, even after the third use. However, functionalized niobias showed severe decrease in activity. |
publishDate |
2021 |
dc.date.issued.fl_str_mv |
2021-06-08 |
dc.date.accessioned.fl_str_mv |
2022-05-10T15:34:20Z |
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 |
COSTA, Gustavo Carvalho da. Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo. 2021. 117 f. Dissertação (Mestrado em Engenharia Química) - Faculdade de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2021. |
dc.identifier.uri.fl_str_mv |
http://www.bdtd.uerj.br/handle/1/17712 |
identifier_str_mv |
COSTA, Gustavo Carvalho da. Nióbias sulfatadas e fosfatadas como catalisadores ácidos na esterificação de ácido acético com etanol visando o beneficiamento de bio-óleo. 2021. 117 f. Dissertação (Mestrado em Engenharia Química) - Faculdade de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2021. |
url |
http://www.bdtd.uerj.br/handle/1/17712 |
dc.language.iso.fl_str_mv |
por |
language |
por |
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 |
Universidade do Estado do Rio de Janeiro |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Engenharia Química |
dc.publisher.initials.fl_str_mv |
UERJ |
dc.publisher.country.fl_str_mv |
Brasil |
dc.publisher.department.fl_str_mv |
Centro de Tecnologia e Ciências::Instituto de Química |
publisher.none.fl_str_mv |
Universidade do Estado do Rio de Janeiro |
dc.source.none.fl_str_mv |
reponame:Biblioteca Digital de Teses e Dissertações da UERJ instname:Universidade do Estado do Rio de Janeiro (UERJ) instacron:UERJ |
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Universidade do Estado do Rio de Janeiro (UERJ) |
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UERJ |
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UERJ |
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Biblioteca Digital de Teses e Dissertações da UERJ |
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Biblioteca Digital de Teses e Dissertações da UERJ |
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http://www.bdtd.uerj.br/bitstream/1/17712/2/Disserta%C3%A7%C3%A3o+-+Gustavo+Carvalho+da+Costa+-+2021+-+Completa.pdf http://www.bdtd.uerj.br/bitstream/1/17712/1/license.txt |
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MD5 MD5 |
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Biblioteca Digital de Teses e Dissertações da UERJ - Universidade do Estado do Rio de Janeiro (UERJ) |
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bdtd.suporte@uerj.br |
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