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Medição experimental e modelagem termodinâmica de parâmetros de escoamento a frio do biodiesel de seboLira, Cinthya Petrucia Gomes de 31 January 2013 (has links)
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Previous issue date: 2013 / Um dos problemas enfrentados pelo uso do biodiesel é a solidificação parcial ou total, dificultando sua fluidez,levando a interrupção do fluxo do combustível e o entupimento do sistema de filtração e injecão, ocasionando problemas na partida do motor em climas de baixas temperaturas. Além do mais, a propriedade de estabilidade do biodiesel em relação à formação de depósitos é objeto de estudo nos setores produtivo e comercial pois compromete as operações de transferência e armazenamento do produto na sua rota tecnológica e na logística de distribuição. O trabalho consiste em análises experimentais e simulações computacionais no biodiesel oriundo de gordura animal cedido pela indústria JBS. Foi usado aditivo anticongelante, Viscoplex, cedido pela Evonik Industries,diesel S50 cedido pela BR Distribuidora Suape e óleo soja comercial, para tentar melhorar as propriedades de fluxo a frio do biodiesel estudado. Uma parcela do trabalho foi a realização de análises físico químicasno biodiesel de gordura animal com intuito de estudar a formação de um precipitado de natureza desconhecida formado a baixas temperaturas. A outra parcela consistiu em determinar o ponto de turvação por simulação computacional e comparar com o obtido experimentalmente. Para realização do modelo computacional se fez necessário o uso de análises cromatográficas para determinação da composição mássica do biodiesel estudado, bem como as propriedades termofísicas dos ésteres de ácidos graxos saturados e insaturados, em particular no que se refere a entalpia de fusão e temperatura de fusão.
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Síntese e modificação química de biodiesel para formação de epóxidos e carbonatos cíclicos com potencial biodegradabildade /Paiano, Murillo da Silva. January 2015 (has links)
Orientador: Eduardo René Pérez González / Banca: Luiz Carlos da Silva Filho / Banca: Gil Valdo José da Silva / O Programa de Pós Graduação em Ciência e Tecnologia de Materiais, PosMat tem carater institucional e integra as atividades de pesquisa em materiais de diversos campi / Resumo: A modificação química do biodiesel tem sido uma proposta interessante para obtenção de diversos compostos oleoquímicos com propriedades e aplicações semelhantes aos derivados do petróleo, com o diferencial de serem obtidos através de rotas limpas e ambientalmente benigmas, utilizando insumos naturais como óleo vegetal e dióxido de carbono, atendendo diversos princípios da Química Verde. Este trabalho têm como proposta realizar uma série de modificações químicas do biodiesel de linhaça, partindo de sua síntese, epoxidação e cicloadição de CO2 para obtenção de epóxidos e carbonatos cíclicos biodegradáveis. O biodiesel de linhaça foi produzido através de catálise com ácido de Lewis (NbCl5) e teve seu teor de insaturação concentrado via purificação com uréia. A epoxidação do biodiesel concentrado teve sua cinética acompanhada pelo progresso do valor de oxigênio oxirano além de ser estudada via GC-FID e GC-MS. Os carbonatos cíclicos foram obtidos pela cicloadiação de CO2 supercrítico nos epóxidos catalisada por TEAB sem solvente e mostraram-se bons reagentes frente a diversas aminas para formação de carbamatos (uretanos). Espectros de FT-IR e RMN (1H e 13C) identificaram as transformações de todos os principais grupos funcionais comprovando êxito nas modificacões químicas propostas / Abstract: The chemical modification of biodiesel has been an interesting proposal for obtaining various oleochemical compounds with similar porperties and aplications to petroleum derivates, with the difference of being obtained through clean and environmentally benign routes, using natural feedstock as vegetables oil and carbon dioxide, according to several principles of Green Chemistry. This work proposes to conduct a series of chemical modifications of flaxseed biodiesel, from its synthesis, epoxidation and cycloaddtion of CO2 to obtain biodegradable epoxides and cyclic carbonates. The flaxseed biodiesel was produced through Lewis acid catalysis (NbCl5) and had its unsaturation content concentrated by urea purification. The epoxidation of the concentrated biodiesel had its kinetics monitored by the evolution of oxygen oxirane value and studied by GC-FID and GC-MS. The cyclic carbonates were obtained from the solventless cycloaddition of supercritical CO2 in the opoxides catalyzed by TEAB, and have shown good reactants for a wide range of amines to from its respective carbamates (urethanes). FT-IR and NMR (1H and 13C) spectra identified the transformatios of all maior functional groups proving successful in the proposed chemical modifications / Mestre
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Uso de glicerol como fonte de conversão energética nos processos de co-digestão anaeróbia e ensilagem /Schwingel, Alice Watte, 1990. January 2017 (has links)
Orientador: Jorge de Lucas Junior / Coorientador: Ana Carolina Amorim Orrico / Banca: Monica Sarolli Silva de Mendonça Costa / Banca: Laura Vanessa Cabral da Costa / Banca: Valeria Cristina Rodrigues Sarnighausen / Banca: Maura Seiko Tsutsui Esperancini / Resumo: A produção de biodiesel gera altas quantidades de glicerina bruta de baixa qualidade, com baixo conteúdo de glicerol, que requer purificação para atender o mercado consumidor ou pode ser usado em sistemas de reciclagem, nos quais os resíduos poluentes resultarão em energia limpa ou energia na forma de alimento. Para empregar esta glicerina nesses sistemas, ela deve estar associada a outro resíduo de modo a equilibrar a digestão do meio e aumentar o rendimento energético ou estar associado a uma forrageira com características que suporte sua inclusão no processo de ensilagem. Com esta pesquisa, objetivou-se avaliar a influência de conteúdos de glicerol na composição da glicerina (40% (G40), 60% (G60) e 80% (G80)) sobre o desenvolvimento da co-digestão anaeróbia com excretas de aves de postura com as inclusões de níveis de glicerol de 0, 1, 2, 3 e 4% dos sólidos totais (ST) e também com níveis de glicerol de 0, 2, 4 e 6% na matéria seca (MS) ensilada sobre o desempenho do processo de ensilagem de capim Urochloa brizantha cv. Piatã. O delineamento experimental utilizado nos dois experimentos foi o inteiramente casualizado em esquema fatorial duplo, com análise da interação entre os dois fatores (pureza das glicerinas e níveis de glicerol). O efeito das purezas foi avaliado por teste de média e das doses de glicerol por contrastes ortogonais, a fim de encontrar as doses ideais por meio dos modelos ajustados. A pureza das glicerinas teve efeito semelhante para maioria dos parâmetr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Biodiesel production generates high amounts of low-quality crude glycerin, with low glycerol content, which requires purification to meet the consumer market or even to be used in recycling systems, in which the polluting residues will result in clean energy or energy component of animal food. In order to employ this glycerin in those systems, it must be associated with another residue so as to balance the digestion medium and increase energy yield or be associated with a forage with characteristics that support its inclusion in the ensilage process. This research aimed to evaluate the influence of glycerol contents within glycerin composition [40% (G40), 60% (G60) and 80% (G80)] and addition of glycerol levels (0, 1, 2, 3 and 4% of total solids - TS) on anaerobic codigestion with laying-hen manure and also with glycerol levels of 0, 2, 4 and 6% (of the ensiled dry matter) on the performance of the grass ensilage process Urochloa brizantha cv. Piatã. The experimental design, in the two experimentals, was completely randomized in a double factorial design, with analysis of the interaction between both factors (glycerin purity and glycerol additions). Purity effect was assessed by mean tests and glycerol doses by orthogonal contrasts to find optimal doses through adjusted models. G40 showed performance 3.5% and 2.8% lower than the G60 and G80, respectively, over biogas productions by TSadded, and even lower biogas and methane productions by CODreduced. The inclusion of 2.5% gly... (Complete abstract click electronic access below) / Doutor
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Characterisation of biodiesel from Litsea glutinosaPerumal, Alicia Ann 08 August 2014 (has links)
Submitted in complete fulfillment for the Degree of Master of Technology: Biotechnology, Durban University of Technology, Durban, South Africa, 2014. / Global warming is a major concern to the world’s population. It is caused by greenhouse gases that result from the burning of fossil fuel. The fossil fuel reserves are rapidly depleting as the needs and wants of man in the world increases. Biodiesel is one of the solutions proposed to remedy this environmental crisis facing the world today. The aim of this study was to characterise the biodiesel that can be produced from the oil of Litsea glutinosa by transesterification. Biodiesel can be used in a diesel engine without modification and be produced from many different natural renewable oil sources such as algae, plants and kitchen waste material. Jatropha curcas has been identified as a potential producer of oil for biodiesel. The biodiesel properties of Jatropha curcas meet the required American Society for Testing and Materials (ASTM) standards. The fruit of Jatropha curcas contains 40.0% lipids. The oil has a saponification number of 202.6 and an iodine value of 93.0. However Jatropha curcas cannot be grown in South Africa because it is a highly invasive plant. Cetane number is the most important parameter of biodiesel. The higher the cetane value, the better the quality of the biodiesel. Oil from Jatropha curcas has a cetane number of 57.1. An alternative is the oil from Litsea glutinosa, which is found as a naturalised free forest along the South African coastline, and is also found in many Asian countries. It has many medicinal properties, however, it is not edible and hence its use for biodiesel does not add to the debate of fuel versus food production. The cetane number of oil from Litsea glutinosa is 64.79, which is ideal for ignition, and the fruit with 61.29% lipids can yield valuable quantities of biodiesel. Thus, the aim of the research was to determine the potential of Litsea glutinosa as a source of biodiesel. Furthermore, to maintain a sustainable source, Litsea glutinosa was micropropagated, and transformation of Litsea glutinosa was attempted for hairy root cultures.
The Clevenger apparatus was used to extract fatty acids from dried crushed fruit of Litsea glutinosa. Fatty acids were converted to fatty acid methyl esters by transesterification. Transesterification was conducted in the presence of nitrogen and the reaction was catalysed with a mixture of methanol and sodium hydroxide (NaOH). The ratio 1 : 3 of oil to catalyst mixture was used for optimum transesterification to ensure a forward reaction
and it was transferred to a separating funnel to allow the glycerol and fatty acid methyl esters to separate. GC-MS was used to determine the fatty acids. The iodine number, saponification number, acid value, viscosity, kinematic viscosity, density, specific gravity, thermostability, distillation point and sulphur content were determined. The seeds of Litsea glutinosa were germinated and tissue culture callus was produced from the seeds and leaves. The leaves and stems were used to produce hairy root cultures by inoculating them with Agrobacterium rhizogenes.
Litsea glutinosa yielded 61% oil, which included 47 fatty acids in the fruit and 24 fatty acids in the seeds. The fatty acid profile of the oils indicated that the predominant fatty acids present were those that are essential for good quality biodiesel. The dominant fatty acids found in the fruit were 65.4% 9-octadecenoic acid and 13.6% hexadecanoic acid. The dominating fatty acids found in the seeds contained 36.3% 9-octadecenoic acid, 13.9%, hexadecanoic acid and 39.1%, dodecanoic acid. The iodine value was 6.3. The saponification value was 274. The acid value was 0.45 mg KOH. g-1. The viscosity was 22.48 mm2. s-1 and the kinematic viscosity was 23.84 mm2. s-1. The density was 942.69 kg. m-3 and the specific gravity was found to be 0.9 g. cm-3. The distillation temperature ranged between 52.2°C to 610.2°C. The sulphur content was found to be 383 µg. ml-1.
These characteristics indicate that Litsea glutinosa can be used as a source of biodiesel, because the properties meet the required ASTM standards. However, the production of biodiesel from Litsea glutinosa has not been commercialised because the production of fuel is dependent on the fruit of the plant, which is seasonal. To overcome this, a part of this study investigated micropragation of Litsea glutinosa and transformation of Litsea glutinosa by Agrobacterium rhizogenes into hairy roots and attempts where made to determine whether fatty acid could be produced by these techniques. Callus cultures were grown on MS media and McCowns woody plant media supplemented with 1 ml BAP and 1 ml 2,4-D per 1 L of media. Callus cultures were obtained in the light. However, Litsea glutinosa resisted transformation by Agrobacterium rhizogenes.
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Technical and Economic Feasibility of Biodiesel Production in Vermont: Evidence from a Farm-Scale Study and a Commercial-Scale Simulation AnalysisStebbins, Emily 02 October 2009 (has links)
Concerns about Vermont‘s dairy farm viability, greenhouse gas emissions, and reliance on fossil fuels have prompted growing interest in the production of biodiesel and oilseed meal from Vermont-grown oilseed crops. The idea is that Vermont farmers could grow and harvest oilseed crops; the seed or beans could be pressed into vegetable oil and oilseed meal; and the oil could be processed into biodiesel, thereby producing both liquid biofuel and protein meal for livestock from Vermont crops. Results from this study indicate that oil, meal, and biodiesel production from sunflowers grown in Vermont is technically feasible, and may be economically feasible at both the farm and commercial scales, depending on scale and market conditions. Farmers, entrepreneurs, and policymakers are intrigued by the potential to decrease Vermont‘s dependency on imported fuels and feed, reduce farms‘ production costs, realize local economic benefits from import substitution, and lower greenhouse gas emissions. Despite the promise of ―Vermont-made‖ biodiesel and oilseed meal, however, it remains largely an unproven concept. Production of oilseed crops is relatively rare in Vermont, especially in quantities sufficient for biodiesel or livestock meal production. The equipment, capital, acreage, and expertise needed to successfully grow, harvest, and process these crops have not been identified, and the economic feasibility, optimal scale, and environmental and macroeconomic impacts of these new enterprises in Vermont is unknown. This study investigates the technical and economic feasibility of producing biodiesel and livestock feed from Vermont oilseeds at a farm scale and a commercial scale. Technical feasibility at the farm scale is assessed using data from two Vermont farms. Enterprise budgets are used to assess the economic feasibility and profitability of the crop, oil and meal, and biodiesel enterprises individually and as a whole under two sets of market conditions. Economic feasibility and environmental and economic impacts of a commercial-scale biodiesel facility in Vermont are assessed using a simulation model. None of the farm-scale enterprises were profitable as budgeted in this analysis, although the commercial-scale plant was more profitable as crude oil prices rose. The most promising enterprise at the farm scale appears to be oil and meal production. This study prompts additional questions regarding the extent to which Vermont crop production should shift to include oilseeds for biodiesel production, the net energy return to the farm, and lifecycle greenhouse gas emissions from on-farm production.
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Avaliação da estabilidade de biodiesel durante a armazenagem /Moser, Daniela, 1990-, Simionatto, Edésio Luiz, 1962-, Universidade Regional de Blumenau. Programa de Pós-Graduação em Química. January 2013 (has links) (PDF)
Orientador: Edesio Luiz Simionatto. / Dissertação (mestrado) - Universidade Regional Blumenau, Centro de Ciências Exatas e Naturais, Programa de Pós-Graduação em Química.
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Caracterização química do biodiesel obtido a partir do óleo de fritura e sua relação com a estabilidade à oxidaçãoMotta, Valnice, 1989-, Simionatto, Edésio Luiz, 1962-, Universidade Regional de Blumenau. Programa de Pós-Graduação em Química. January 2016 (has links) (PDF)
Orientador: Edésio Luiz Simionatto. / Dissertação (Mestrado em Química) - Programa de Pós-Graduação em Química, Centro de Ciências Exatas e Naturais, Universidade Regional de Blumenau, Blumenau.
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Análise da sustentabilidade do biodiesel da mamona no semiárido nordestino / This work has as a hypothesis showing that MAMONA is an available alternative of social insertion for the Northeast semiarid, in relation to biodiesel production. The aim, on the whole, is to demonstrate the environmental, social and economic, as well as institutional availability of MAMONA cultivation in the Northeast semiarid region, having as specific goals: 1) Identify environmental impacts when MAMONA is cultivated; 2) Identify social and economic benefits, as well as institutional ones given by the central government, which is supporting the EUFORBIACEA'S cultivation. In favor of the accomplishment of this study whose research nature is qualitative, it was used a bibliographic and field investigation. The methodology adapted was based on observation, analyses of contents, through a data triangulation prepared with the support of vertical interviews with experts and also through consulting secondary sources of data. It was used Atlas TI program for data treatment that founded all conclusions. As a result, it was confirmed that, in spite of existing sectorial problems in PNPB, mainly in the productive chain, which caused a delay in the process of inserting more families in the Northeast semiarid. The targets of the research were made out, with an exploratory study, based on arguments of several theoreticals in the subject, reaching, this way, the final conclusion: the hypothesis raised up in this work is also stronger because of the numberless reasons and empirical data stated by experts in the matter. (Inglês)Alves, Francisco 24 March 2009 (has links)
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Previous issue date: 2009-03-24 / This work has as a hypothesis showing that MAMONA is an available alternative of social
insertion for the Northeast semiarid, in relation to biodiesel production. The aim, on the whole, is to demonstrate the environmental, social and economic, as well as institutional availability of MAMONA cultivation in the Northeast semiarid region, having as specific goals: 1) Identify environmental impacts when MAMONA is cultivated; 2) Identify social and economic benefits, as well as institutional ones given by the central government, which is supporting the EUFORBIACEA S cultivation. In favor of the accomplishment of this study whose research nature is qualitative, it was used a bibliographic and field investigation. The methodology adapted was based on observation, analyses of contents, through a data triangulation prepared with the support of vertical interviews with experts and also through consulting secondary sources of data. It was used Atlas TI program for data treatment that founded all conclusions. As a result, it was confirmed that, in spite of existing sectorial problems in PNPB, mainly in the productive chain, which caused a delay in the process of inserting more families in the Northeast semiarid. The targets of the research were made out, with an exploratory study, based on arguments of several theoreticals in the subject, reaching,
this way, the final conclusion: the hypothesis raised up in this work is also stronger because of the numberless reasons and empirical data stated by experts in the matter. / Este trabalho tem como hipótese mostrar que a mamona é alternativa viável de inserção social para o semiárido nordestino, na produção do biodiesel. O objetivo geral é mostrar a viabilidade ambiental, socioeconômica e institucional, do cultivo da mamona no semiárido nordestino, tendo como objetivos específicos: (i) Identificar impactos ambientais quando do cultivo da mamona e (ii) Identificar benefícios sócioeconômicos e institucionais disponibilizados pelo governo central, no apoio ao cultivo da euforbiácea. Para a realização deste trabalho, de natureza predominantemente qualitativa, foi utilizada a pesquisa bibliográfica e de campo. Os métodos usados foram o observacional e de análise de conteúdo, por meio da triangulação de dados, trabalhados mediante entrevistas de profundidade com experts da temática e consultas a fontes secundárias de dados. Foi utilizado o programa Atlas TI para tratamento dos dados que fundamentaram todas as conclusões. Como resultado constatou-se que apesar de existirem problemas setoriais no PNPB, especificamente na cadeia produtiva, que retardam o processo de inserção de mais famílias do semiárido nordestino, os objetivos da pesquisa foram atingidos durante as análises das entrevistas, em confronto com o estudo exploratório, baseado nos argumentos de diversos teóricos e chegou-se a conclusão de que a hipótese levantada no trabalho também está mais forte através de inúmeros argumentos e dados empíricos proferidos pelas autoridades no tema.
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Síntese de polímeros oriundos do ácido oleico e derivados do biodiesel de soja e canola para revestimentos de nanopartículas de Fe3O4 E CoFe2O4Moraes, Danielle Costa de January 2016 (has links)
No presente trabalho foi realizada a polimerização de ácidos graxos epoxidados derivados dos biodieseis de soja e canola na presença do anidrido cis-1,2-ciclohexanodicarboxílico e trietilamina. Também é apresentado nesse estudo a síntese de nanopartículas magnéticas de Fe3O4 e CoFe2O4 a partir do método de coprecipitação. O objetivo deste estudo é o recobrimento de nanopartículas magnéticas com polímeros dos ácidos graxos epoxidados visando diminuir a aglomeração destas nanopartículas. Esse recobrimento foi evidenciado através do teste de solubilidade e da análise de infravermelho, onde observou-se bandas de estiramento Fe–O em 570 – 565 cm-1. Através da microscopia eletrônica de transmissão foi observado o aumento do diâmetro das nanopartículas de 12,2 nm (Fe3O4) para 13,2, 13,6 e 14,6 após o recobrimento (PAO-Fe, PAGS-Fe e PAGCa-Fe). Através da difração de raios X foram encontrados valores de 11,4, 10,8, 9,9 e 11,1 nm para as nanopartículas de Fe3O4, PAO-Fe, PAGS-Fe e PAGCa-Fe, enquanto que para as nanopartículas de CoFe2O4, PAO-Co, PAGS-Co e PAGCa-Co esse valor foi de 10,8, 9,8, 10,1 e 10,4, respectivamente. As propriedades magnéticas foram caracterizadas através da magnetização em função do campo magnético e mostrou comportamento superparamagnetico para as nanopartículas de Fe3O4 e ferromagnetico para as nanopartículas de CoFe2O4. Os resultados apresentados neste trabalho demonstram que a metodologia utilizada pode abrir um novo caminho para a pesquisa, uma vez que não foram encontradas informações sobre o recobrimento de nanopartículas de ferro ou cobalto com os polímeros obtidos através dos ácidos graxos dos biodieseis. / In this work the polymerization of epoxidized fatty acids, derived from soybean and canola biodiesel, were performed, in the presence of cis-1,2-cyclohexanedicarboxylic anhydride and triethylamine. The synthesis of magnetic nanoparticles of Fe3O4 and CoFe2O4 are presented, which were obtained from the co-precipitation method. The aim of this study was to coat the synthesized nanoparticles with polymers obtained from epoxidized fatty acids in oreder to reduce the magnetic nanoparticles agglomeration. The nanoparticles coating was evidenced by solubility tests and infrared spectroscopy analysis, in which, the stretching band of Fe-O, at 570-565 cm-1, was observed. Transmission electron microscopy showed the increase in nanoparticles diameter, from 12.2 nm (Fe3O4), to 13.2, 13.6, and 14.6 nm, after their coating with PAO-Fe, PAGS-Fe, and PAGCa-Fe, respectively. The particle size calculated from X-ray diffractograms were 11.4, 10.8, 9.9 and 11.1 nm, for nanoparticles of Fe3O4, PAO-Fe, PAGS-Fe, and PAGCa-Fe, respectively. Whereas, the particles size of CoFe2O4, PAO-Co, PAGS-Co, and PAGCa-Co nanoparticles, were 10.8, 9.8, 10.1 and 10.4 nm, respectively. Magnetic properties were characterized using the Vibranting Sample Magnetometer and a superparamagnetic behavior in iron nanoparticles (Fe3O4) and ferromagnetic in cobalt nanoparticles (CoFe2O4) were observed. The results presented here demonstrated that the methodology can open a new field of investigation, once there is no reports on the coating of iron or cobalt nanoparticles with polymers obtained from the fatty acids of biodiesels.
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Estudo de nanopartículas magnéticas recobertas por polímeros derivados de epóxidos de ácidos graxos do biodieselSilva, Silene Pereira da January 2015 (has links)
Neste trabalho foi investigado o recobrimento de nanopartículas magnéticas com polímeros provenientes de epóxidos do ácido oleico ou dos ácidos graxos do biodiesel de canola. As nanopartículas magnéticas de óxido de ferro foram obtidas pelo método de co-precipitação pela mistura de soluções aquosas de cloreto de ferro (II) e (III) em meio alcalino. Os polímeros utilizados para recobrimento das nanopartículas foram produzidos a partir da abertura do anel epóxido do ácido oleico ou dos ácidos graxos do biodiesel de canola, e posterior polimerização com anidrido cis-1,2-ciclohexanodicarboxílico. A caracterização das nanopartículas recobertas foi realizada por microscopia eletrônica de varredura (MEV-EDS), microscopia eletrônica de transmissão (MET), difração de raios-x (DRX), espectroscopia de infravermelho com transformada de Fourier (FTIR), análise termogravimétrica (TGA), espectroscopia raman, magnetômetro de amostra vibrante (VSM), análise elementar de carbono, hidrogênio e nitrogênio (CHN) e teste de dispersibilidade. As nanopartículas recobertas mostraram alta afinidade pelo meio orgânico após a interação entre os polímeros e nanopartículas magnéticas, tornando-as hidrofóbicas. As micrografias de MEV-EDS demonstraram pouca dispersibilidade entre as nanopartículas recobertas e a composição química de carbono obtidas nestas amostras indicou a presença de polímeros sob a superfície do óxido de ferro. O percentual de carbono também foi obtido pela técnica de CHN, que identificou 12,9% de carbono nas partículas recobertas por polímero do epóxido do ácido oleico e 14,7% por polímero do epóxido de ácidos graxos do biodiesel de canola. As nanopartículas revestidas, analisadas por MET, mostraram aglomerados de formas esféricas e uma larga distribuição de tamanho, com diâmetro médio de 10 nm. Os difratogramas de DRX apresentaram planos cristalográficos característicos de magnetita nas partículas recobertas, como também um alargamento a meia altura dos picos indicando uma diminuição no diâmetro médio dos cristalitos quando comparados as nanopartículas puras. A interação entre o óxido de ferro e os polímeros para revestimento foi caracterizada por espectroscopia no infravermelho e TGA. O FTIR mostrou bandas de grupos (CH2) e (C=O) provenientes dos ácidos graxos dos polímeros, enquanto o TGA apresentou uma perda de massa de 7% entre 600-700 ºC que definiu a interação entre os compostos. O comportamento magnético das amostras recobertas foi obtido por magnetometria que apresentou curvas de saturação de magnetização típicas de materiais superparamagnéticos. / In this work was investigated the coating of magnetic nanoparticles by polymers from oleic acid or fatty acids of canola biodiesel epoxides. The magnetic nanoparticles of iron oxide were obtained from the co-precipitation method by mixing aqueous solutions of iron chloride (II) and (III) in an alkaline medium. The polymers used for coating of the nanoparticles were produced from the opening of the epoxide ring of oleic acid or fatty acids of rape methyl ester, and subsequent polymerization with cis-1,2-cyclohexanedicarboxylic anhydride. The characterization of the coated nanoparticles was performed by scanning electron microscopy (SEM-EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier Transformer Infrared Spectroscopy (FTIR), thermal gravimetric analysis (TGA), raman spectroscopy, vibrating sample magnetometer (VSM), elemental analysis of carbon, hydrogen and nitrogen (CHN) and dispersibility test. The coated nanoparticles showed high affinity for the organic medium after the interaction between the polymers and magnetic nanoparticles, making them hydrophobic. Micrographs SEM-EDX showed low dispersibility of the coated nanoparticles and the chemical composition of carbon indicated the presence of polymers on the surface of the iron oxide. The carbon percentage was also obtained by the CHN technique, identified 12.9% of carbon particles coated with the polymer of oleic acid and 14.7% of polymer fatty acids of rape methyl ester. The images of the coated nanoparticles analyzed by TEM showed agglomerated with spherical shapes and a broad size distribution with an average diameter close to 10 nm. The XRD showed characteristic crystallographic planes in the coated particles of magnetite, as well as a broadening of the peaks at half height, indicating a decrease in the average crystallite diameter when compared to pure nanoparticles. The interaction between iron oxide and polymers were characterized by infrared spectroscopy and TGA. FTIR showed bands groups (CH2) and (C=O) from the polymers of fatty acids, while the TGA showed a weight loss of 7% between 600-700 °C which defines the interaction of the compounds. The magnetic behavior of the samples coated was obtained by VSM and showed typical saturation magnetization curves of superparamagnetic material.
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