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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento e caracteriza??o de biolubrificante a partir do ?leo de carna?ba aditivado com micropart?culas e nanopart?culas de grafite

Cavalcanti, Synara Lucien de Lima 29 January 2018 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-20T17:21:12Z No. of bitstreams: 1 SynaraLucienDeLimaCavalcanti_TESE.pdf: 4087598 bytes, checksum: 3742f5acd410c92f39cb86294da47261 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-22T13:32:34Z (GMT) No. of bitstreams: 1 SynaraLucienDeLimaCavalcanti_TESE.pdf: 4087598 bytes, checksum: 3742f5acd410c92f39cb86294da47261 (MD5) / Made available in DSpace on 2018-03-22T13:32:34Z (GMT). No. of bitstreams: 1 SynaraLucienDeLimaCavalcanti_TESE.pdf: 4087598 bytes, checksum: 3742f5acd410c92f39cb86294da47261 (MD5) Previous issue date: 2018-01-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O lubrificante ? respons?vel por reduzir o desgaste relativo ao atrito, proteger o metal contra a oxida??o, corros?o e dissipar o calor excessivo, tornando-se essencial para o equil?brio de um sistema mec?nico, consequentemente prolongando a vida ?til de tal sistema. A origem dos ?leos lubrificantes ?, em geral, mineral sendo extra?dos a partir do petr?leo. Mas a busca por uma nova fonte de produ??o de lubrificantes faz-se necess?rio para suprir futuras demandas e diminuir os poss?veis danos ambientais. O ?leo vegetal ? um recurso renov?vel e biodegrad?vel, e a sua utiliza??o implica em vantagens nos aspectos ambientais, sociais e econ?micos, apresentando-se como uma mat?ria prima de grande potencial para a produ??o de lubrificantes. De acordo com a literatura, o ?leo vegetal de carna?ba apresenta excelentes propriedades e desempenho superior em rela??o a sua capacidade de reduzir o desgaste relativo ao atrito e a sua capacidade de dissipa??o de calor quando comparado com um ?leo comercial similar. Este projeto tem como objetivo desenvolver e caracterizar um material biolubrificante aditivado com micropart?culas e nanopart?culas de grafite a partir do ?leo de carna?ba. O ?leo de carna?ba in natura foi submetido a uma an?lise de estabilidade oxidativa, estabilidade t?rmica, e an?lise de sua composi??o qu?mica. As micropart?culas e nanopart?culas de grafite foram desenvolvidas em um moinho planet?rio de alta energia e caracterizadas atrav?s das an?lises em MEV, MEV-FEG, DRX, FRX e EDX. As concentra??es de grafite nas amostras de biolubrificante foram 0g/L, 0,5g/L e 2g/L. Para caracterizar o biolubrificante foram realizadas as an?lises da microestrutura, de massa espec?fica, viscosidade, ?ndice de acidez, estabilidade t?rmica, condutividade t?rmica e resistividade t?rmica. A efici?ncia de lubrifica??o e a capacidade de dissipa??o de calor por gradiente de temperatura foram analisadas em um sistema mec?nico simulado em bancada (EPEDRA). Diante das an?lises conclui-se que o ?leo de carna?ba in natura, BiolubC 2.0M e BiolubC 2.0N podem ser utilizados eficientemente como biolubrificantes, observadas as caracter?sticas e necessidades do sistema mec?nico. / The lubricant is responsible for reducing friction-related wear, protecting the metal against oxidation, corrosion and dissipating excessive heat, making it essential for the balance of a mechanical system, thereby prolonging the life of such a system. The origin of the lubricating oils is, in general, mineral being extracted from petroleum. But the search for a new source of lubricant production is necessary to meet future demands and reduce possible environmental damages. Vegetable oil is a renewable and biodegradable resource and its use implies advantages in environmental, social and economic aspects, presenting as a raw material of great potential for the production of lubricants. According to the literature, the carnauba oil has excellent properties and superior performance in relation to its ability to reduce friction-related wear and its heat dissipation capacity when compared to a similar commercial oil. This project aims to develop and characterize a biolubricant material added with microparticles and graphite nanoparticles from carnauba oil. The in natura carnauba oil was subjected to oxidative stability, thermal stability, and analysis of its chemical composition. The microparticles and nanoparticles were developed in a high energy planetary mill and characterized by SEM, DRX, FRX and EDX analysis. The graphite concentrations in the biolubricant samples are 0g/L, 0,5g/L and 2g/L. In order to characterize the biolubricant, microstructure, specific gravity, viscosity, acidity index, thermal stability, thermal conductivity and thermal resistivity analyzes were performed. The lubrication efficiency and the heat dissipation capacity by temperature gradient were analyzed in a simulated mechanical bench system. In view of the analysis, it is concluded that the in natura carnauba oil, BiolubC 2.0M and BiolubC 2.0N can be efficiently used as biolubricants, observing the characteristics and needs of the mechanical system.
2

Caracteriza??o do ?leo de carna?ba para uso como biolubrificante

Cavalcanti, Synara Lucien de Lima 03 February 2014 (has links)
Made available in DSpace on 2014-12-17T14:58:23Z (GMT). No. of bitstreams: 1 SynaraLLC_DISSERT.pdf: 6169690 bytes, checksum: faa4a0309db3cf8ab6507bf4b090a9cc (MD5) Previous issue date: 2014-02-03 / Lubricant is responsible for reducing the wear on the friction protect the metal against oxidation, corrosion and dissipates excess heat, making it essential for the balance of a mechanical system, consequently prolonging the useful life of such a system. The origin of lubricating oils is usually mineral being extracted from the petroleum. But the search for a new source of production of lubricants and fuels it is necessary to meet future demands and reduce the possible environmental damage. For this reason, looking alternative means to produce certain products derived from petroleum, such as biodiesel, for example. Returning to the realm of lubricants, also one realizes this need for new raw materials for their production. Vegetable oil is a renewable resource and biodegradable, and its use entails advantages in environmental, social and economic. The development of this project aims to characterize the carnauba oil as a lubricant plant, or biolubricant. To analyze the oil carnauba tests as checking density, flash point, fire point, viscosity, viscosity, acid number, pH, copper corrosion, thermal conductivity and thermal resistivity were developed. In addition, for conducting the wear on the friction and the gradient of the system temperature, the analysis equipment is designed for wear on the friction. Based on these results, it is observed that the oil carnauba show good correlation to its application as biolubricant / O lubrificante ? respons?vel por reduzir o desgaste relativo ao atrito, proteger o metal contra a oxida??o, corros?o e dissipar o calor excessivo, tornando-se essencial para o equil?brio de um sistema mec?nico, consequentemente prolongando a vida ?til de tal sistema. A origem dos ?leos lubrificantes ?, em geral, mineral sendo extra?dos a partir do petr?leo. Mas a busca por uma nova fonte de produ??o de lubrificantes e combust?veis faz-se necess?rio para suprir futuras demandas e diminuir os poss?veis danos ambientais; por este motivo, procuram-se formas alternativas para produ??o de determinados produtos derivados do petr?leo, como o biodiesel, por exemplo. Voltando para a esfera dos lubrificantes, percebe-se tamb?m essa necessidade de novas mat?riasprimas para a sua produ??o. O ?leo vegetal ? um recurso renov?vel e biodegrad?vel, e a sua utiliza??o implica em vantagens nos aspectos ambientais, sociais e econ?micos. O desenvolvimento deste projeto tem como objetivo caracterizar o ?leo de carna?ba como um lubrificante vegetal, ou biolubrificante. Para analisar o ?leo de carna?ba foram desenvolvidos ensaios como verifica??o de massa espec?fica, ponto de fulgor, ponto de combust?o, viscosidade, ?ndice de viscosidade, ?ndice de acidez, pH, corros?o ao cobre, condutividade t?rmica e resistividade t?rmica. Em complemento, para realizar an?lises de desgaste relativo ao atrito e do gradiente de temperatura do sistema, foi desenvolvido o equipamento para an?lise de desgaste relativo ao atrito. Diante dos resultados obtidos, observa-se que o ?leo de carna?ba apresenta uma boa correla??o para sua aplica??o como biolubrificante

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