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Previous issue date: 2014-01-30 / Among the heterogeneous catalysts materials made from niobium show up as an alternative to meet the demand of catalysts for biodiesel production. This study aims to evaluate the potential of a heterogeneous catalyst derived from a complex of niobium in the reaction of methyl esterification of oleic acid. The catalyst was synthesized after calcination at different temperatures of a niobium complex ((NH4)3[NbO(C2O4)3].H2O) generating a niobium oxide nanostructure with a different commercial niobium oxide used to synthesize the complex. The commercial niobium oxide, the complex niobium and niobium catalyst were characterized by thermogravimetry (TG and DTA), surface area analysis (BET), scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing the catalyst has researched morphological and crystallographic indicating a catalytic potential higher than that of commercial niobium oxide characteristics. Factorial with central composite design point, with three factors (calcination temperature, molar ratio of alcohol/oleic acid and mass percentage of catalyst) was performed. Noting that the optimal experimental point was given by the complex calcination temperature of 600?C, a molar ratio alcohol/oleic acid of 3.007/1 and the catalyst mass percentage of 7.998%, with a conversion of 22.44% oleic acid in methyl oleate to 60 min of reaction. We performed a composite linear and quadratic regression to determine an optimal statistical point of the reaction, the temperature of calcination of the complex at 450?C, the molar ratio of alcohol/oleic acid 3.3408/1 and mass percentage of catalyst of 7.6833% . Kinetic modeling to estimate parameters for heterogeneous catalysis it set well the experimental results with a final conversion of 85.01% with 42.38% of catalyst and without catalyst at 240 min reaction was performed. Allowing to evaluate the catalyst catalytic studied has the potential to be used in biodiesel production / Dentre os catalisadores heterog?neos os materiais a base de ni?bio mostram-se como uma alternativa para suprir a demanda de catalisadores para a produ??o de biodiesel. O presente trabalho visa avaliar o potencial de um catalisador heterog?neo derivado de um complexo de ni?bio na rea??o de esterifica??o met?lica do ?cido oleico. O catalisador foi sintetizado ap?s a calcina??o em diferentes temperaturas de um complexo de ni?bio ((NH4)3[NbO(C2O4)3].H2O) gerando um ?xido de ni?bio com uma nanoestrutura diferente do ?xido de ni?bio comercial, usado para sintetizar o complexo. O ?xido de ni?bio comercial, o complexo de ni?bio e o catalisador de ni?bio foram caracterizados por termogravimetria (TG e DTA), an?lise de ?rea superficial (BET), microscopia eletr?nica de varredura (MEV) e difra??o de raios-X (DRX), demostrando que o catalisador pesquisado possui caracter?sticas morfol?gicas e cristalogr?ficas que indicam um potencial catal?tico superior ao ?xido de ni?bio comercial. Foi realizado um planejamento fatorial composto com ponto central, com tr?s fatores (temperatura de calcina??o, raz?o molar de ?lcool/?cido oleico e percentual m?ssico de catalisador). Verificando que o ponto ?timo experimental se deu mediante a temperatura de calcina??o do complexo em 600?C, uma raz?o molar de ?lcool/?cido oleico de 3,007/1 e percentual m?ssico de catalisador de 7,998%, apresentando uma convers?o de 22,44% do ?cido oleico em oleato de metila em 60 min de rea??o. Realizou-se uma regress?o linear e quadr?tica composta para se determinar de um ponto ?timo estat?stico da rea??o, sendo a temperatura de calcina??o do complexo em 450?C, raz?o molar de ?lcool/?cido oleico de 3,3408/1 e percentual m?ssico de catalisador de 7,6833%. Foi realizada uma modelagem cin?tica para estima??o de par?metros para a cat?lise heterog?nea que se ajustou satisfatoriamente aos resultados experimentais com uma convers?o final de 85,01% com catalisador e de 42,38% sem o catalisador em 240 min de rea??o. Permitindo avaliar que o catalisador estudado possui potencial catal?tico para ser utilizado na produ??o de biodiesel
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15854 |
| Date | 30 January 2014 |
| Creators | Oliveira, Samuel Alves de |
| Contributors | CPF:13681389420, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781094H3, Silva, Gilson Garcia da, CPF:56634161453, http://lattes.cnpq.br/8681275097040450, Gomes, Kalyanne Keyly Pereira, CPF:00840465467, http://lattes.cnpq.br/9872554247495034, Sousa, Jo?o Fernandes de, Souza, Carlson Pereira de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Qu?mica, UFRN, BR, Pesquisa e Desenvolvimento de Tecnologias Regionais |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | Portuguese |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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