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Desenvolvimento de um sistema de liberação controlada de princípios ativos do oleo de Azadirachta indica A. Juss em matriz de poli(álcool vinílico) (PVA) para aplicações em veterinária / Development of a controlled delivery system of Azadirachta indica A. Juss active agents oil in poly(vinyl alcohol) (PVA) matrix for veterinary applicationsANDRADE, ANDREIA B.N. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:22Z (GMT). No. of bitstreams: 0 / Sistemas de liberação controlada vêm sendo cada vez mais utilizados em diferentes áreas tendo em vista sua aplicabilidade que os tornam uma tecnologia capaz de atender as necessidades econômicas e ambientais uma vez que permitem a utilização de princípios ativos em quantidades precisas e apenas nos locais desejados. Dentre a diversidade de opções de matrizes utilizadas nesses sistemas o poli(álcool vinílico) tem sido bastante empregado e pode ser obtido pela técnica de ciclos térmicos. Azadiractina, um princípio ativo encontrado em óleo de semente de Nim tem sido descrita como repelente de diferentes tipos de insetos e apresenta grande aplicabilidade na agricultura. Com base nas propriedades desse composto, propôs-se o desenvolvimento de um sistema de liberação controlada para combate a pulgas Ctenocephalides felis felis. No presente trabalho, foram realizadas caracterizações físico-químicas das matrizes e dispositivos através de ensaios de fração gel, intumescimento, calorimetria exploratória diferencial e microscopia eletrônica de varredura e caracterizações biológicas quanto à citotoxicidade do óleo de Nim, matrizes e dispositivos e bioensaio para análise do comportamento das pulgas na presença do óleo de Nim. As caracterizações físico-químicas permitiram a escolha da matriz mais adequada para o desenvolvimento do dispositivo. As caracterizações biológicas demonstraram ausência de citotoxicidade do óleo de Nim, das matrizes e dos dispositivos e o bioensaio resultou em 40% de mortalidade das pulgas testadas. Na cinética de liberação, verificou-se que todos os agentes encapsulantes utilizados permitiram a liberação de princípios ativos do óleo de Nim. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Novel Biobased Resins using Sucrose Esters of Plant OilsPan, Xiao January 2011 (has links)
Interest in using renewable raw materials to prepare biobased monomers, polymers, and materials is rapidly increasing. The goal of the research described is to develop branched polyesters of plant oil fatty acids, using different core pol yo ls (i.e. sucrose, dipentaerythritol, and tripentaerythritol) and plant oils (i.e. linseed, safflower, and soybean), into curing systems that have potential uses in applications such as coatings, composites, and adhesives. This study is mainly focused on the use of sucrose as the core
polyol in the soyate resins. Sucrose esters and their derivatives have a compact structure, high density, and high functionality-double bonds, epoxides, or hydroxyls. When considering the use of sucrose
ester compounds to form cross linked materials, the rigid core of sucrose can potentially impart hardness to the thermoset, and the high functionality can lead to rapid gelation and high cross link density. Thus, these novel biobased resins using sucrose esters of plant oils have the potential to be a significant advance in biobased resin technology, as well as to be competitive with the conventional petroleum-based resins.
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Classificação e predição da viscosidade de óleos vegetais usando medidas de RMN e análise multivariada. / Classification and prediction of the viscosity of vegetable oils using NMR measurements and multivariate analysis.PÊ, Patrícia Rodrigues. 16 October 2018 (has links)
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Previous issue date: 2009-08 / CNPq / Os óleos vegetais são fontes alimentares de alto valor calórico e de ácidos graxos essenciais. Além disso, a similaridade de suas moléculas com o petrodiesel é uma das vantagens para a produção de biodiesel. No cenário mundial sua valorização vem crescendo como fator de agregação de valor de dupla competição entre alimento e de uso energético. Com isto, surge naturalmente a necessidade de mecanismos que garantam a qualidade desses produtos. Para tanto, as ferramentas disponíveis destroem a amostra, possuem baixa frequência de processamento e geram grande volume de resíduos. Objetivou-se, neste contexto, desenvolver modelos exploratórios e de calibração multivariada com medidas não destrutivas e rápidas de RMN *H de baixo campo e de PCA (Principal Components of Analisys), HCA (Hierarchical Clusters Analisys), SIMCA (Soft Independent Modelling of Class Analogy), MLR (Multiple Linear Regression), PCR (Principal Components Regression) e PLS (Partial Least Squares). Os sinais de RMN *H foram obtidos de um total de n = 65 amostras de sete classes de óleo vegetal (algodão, n = 15; soja, n = 15; azeite de oliva, n = 15; arroz, n = 5; girassol, n = 5; milho, n = 5 e canola, n = 5). As medidas foram realizadas em triplicatas autênticas usando 150,0 mL de cada amostra. A partir dos sinais obtidos foram empregadas técnicas de PCA, HCA, SIMCA, MLR, PCR e PLS. Na PCA, o gráfico dos escores evidencia a formação de
classes distintas com boa separação para algodão, soja e oliva; em 4 PCs se obtém 98,4 % de variância explicada. A validação dos resultados da PCA foi executada com uma HCA, em que o comportamento observado é explicado pela composição de ácidos graxos de cada classe de óleo vegetal. Com essas informações preliminares foram desenvolvidos modelos SIMCA para o qual selecionaram-se amostras ao acaso, para constituir os conjuntos de treinamento, validação e predição. Os modelos SIMCA previram 100% de acerto para as classes de algodão, soja e oliva. Os modelos PCR e PLS para predição da viscosidade foram mais robustos em relação à MLR. Os erros relativos de predição da viscosidade em relação à medida de referência foram sempre menores que 6,3%. Diante essas observações, a RMN H1 de baixo campo e análise multivariada permitem a classificação de óleos vegetais e a predição de sua viscosidade de forma direta, não destrutiva, não invasiva, sem o uso de reagentes, sem a geração de resíduos e com maior rapidez (30 s). / Vegetable oils are one of the most caloric food sources. Furthermore, the similarity of their
fatty acid chains with petrodiesel is one of the advantages of biodiesel production. In the
world, its use is growing as a source of added value of dual competition between food and
energy use. But the tools used in the process of quality control of vegetable oils have technical limitations, such as the destruction of the sample, low frequency processing and generation of large volumes of waste. In this context, it was aimed to develop models exploratory of the multivariate calibration using non-destructive and rapid measures of low-field IH NMR and PCA, HCA, SIMCA, MLR, PCR and PLS. The signs of relaxation in NMR of T2 were obtained from a total of 65 samples of seven kinds of vegetable oil (cotton, n = 15; soybean, n = 15, olive oil, n = 15; rice, n = 5; sunflower , n = 5; maize, n = 5; canola, n = 5). The measurements were performed in a total of three replicates authentic using 150 mL of sample. The instrument used was a spectrometer 7005 with Oxford MQA electromagnet of 0.47 T of 5 MHz from the signal obtained, to use the techniques of PCA, HCA, SIMCA, MLR, PCR and PLS. In PCA, the graph shows the training of scores of different classes with good separation for cotton, soybean and olive. On four PCs you get 98.4% of variance explained. To validate the results of a PCA was performed HCA. The graph shows the dendogram obtained with an anomalous two samples of soybean and one olive. Moreover, there is a greater similarity between the classes of soybean and olive than for cotton. The observed behavior is explained by the distribution of fatty acids in triglycerides of molecules of each class. With this preliminary information SIMCA models were developed. For this, the samples were selected randomly to be the sets of training, validation and prediction. AH samples were correctly classified at 95% probability. The PCR of multivariate calibration model to predict the viscosity was more robust for MLR and PLS. The relative errors of prediction of the viscosity compared to the reference were less than 6,3%. Considering the observations, the *H low field NMR and multivariate analysis allow the classification of vegetable oils and their prediction of viscosity of a direct, non-destructive, non-invasive, without generating waste and rapid (30s).
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Mutation of Eremothecium gossypii and statistical media optimization to increase riboflavin productionGovender, Sharon January 2011 (has links)
Submitted in fulfilment of the requirements of the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2011. / Eremothecium gossypii has the ability to utilize vegetable oils as a carbon source to produce riboflavin. This organism has been known to produce as much as 40 000 times more riboflavin than it requires after genetic modification on simple sugars. Adaptation of this organism to various oil substrates for riboflavin production has been poorly investigated. The aim of this research was thus to investigate the production of riboflavin by Eremothecium gossypii, on various oils and to improve production by mutating the organism and optimising media components using Design of Experiments (DOE). Nine overproducing mutants were obtained after mutating with various concentrations of ethylmethane sulphonate (EMS), n-methyl-n‟-nitro-n-nitrosoguanidine (MNNG) and Ultraviolet light. Riboflavin overproducing mutants were screened on an itaconate-containing medium; the colonies appeared yellow instead of white in the case of the wild-type. The itaconate screening medium isolated mutants with an isocitrate lyase that was insensitive to feedback inhibition. Mutations performed using EMS increased the ability of E. gossypii to produce riboflavin by 611% (7-fold) compared to the wild-type. This was achieved with soybean oil as a carbon source and was better than the other five oils used. Using DOE, fractional factorial experiments were carried out to optimise media components for riboflavin production on soybean oil. The total riboflavin produced by E. gossypii mutant EMS30/1 increased from 59.30 mg l-1 on a standard O&K medium using soybean oil as a carbon source to 100.03 mg l-1 on a DOE improved O&K medium, a 69% increase. The final optimised growth medium was determined from a central composite design using response surface plots together with a mathematical point-prediction tool and consisted of 5.0 g l-1 peptone, 5.0 g l-1 malt extract, 5.1 g l-1 yeast extract, 0.64 g l-1 K2HPO4, 0.6 g l-1 MgSO4 and 20 g l-1 soybean oil. Fractional factorial and central composite media optimization designs increased riboflavin production by several fold over their iterations. There was an overall increase of 1099% (12-fold) in riboflavin production by the mutant grown in an optimized medium compared to the initial riboflavin produced by the wild-type.
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The determination of cis and trans fatty acid isomers in partially hydrogenated plant oilsMarais, Christiaan De Wet 03 1900 (has links)
Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2007. / Trans isomers are formed during the partial hydrogenation process of cis unsaturated fatty acids. The major source of trans fatty acids in the normal person's diet is from margarines and shortenings made from these partially hydrogenated plant and marine oils. In addition to influencing lipid risk factors for cardiovascular disease, trans fatty acids have also been implicated in breast cancer, and in poor fetal development and reduced early infant growth. In reality, trans fatty acids have been consumed for centuries, since they occur naturally in beef, mutton, butter, milk and other dairy products. Though it has been shown that these naturally occurring trans fatty acids have different effects on the health of humans. With the implementation of the new labelling law in South Africa, the trans fatty acids content of food items must be displayed on the food label. Therefore, it becomes necessary to optimise the analytical methodology for the determination of trans fatty acids in foods.
Many publications have reported on the quantification of the total concentration of trans fatty acids in food samples, while less work has been done on the identification and quantification of the different cis and trans unsaturated fatty acid isomers found in foods made from partially hydrogenated oils. The objective of this study was to standardise and optimise an analytical technique to identify and quantify the different cis and trans mono-unsaturated fatty acid isomers in local margarines and bread spreads.
Seeing that fatty acids are the group of lipids most commonly analysed by GLC and the availability of highly polar capillary columns bonded with cyanoalkyl polysiloxan phases, it was decided to use GLC for the identification and quantification of the different cis and trans isomers in a selected group of margarines. It was further decided to evaluate two BPX-70 capillary columns packed with cyanoalkyl polysiloxan phases. The one a 30 m BPX-70 capillary column, normally used for routine fatty acid analyses, and the other a 120 m BPX-70 capillary column.
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Alkaline-catalyzed production of biodiesel fuel from virgin canola oiland recycled waste oilsGuo, Yan, 郭芃 January 2005 (has links)
published_or_final_version / abstract / Mechanical Engineering / Doctoral / Doctor of Philosophy
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Transestérification des huiles végétales par l’éthanol en conditions douces par catalyses hétérogènes acide et basique / Transesterification of vegatable oils by ethanol in mild conditions by acid and base heterogeneous catalystsHamad, Berna 09 December 2009 (has links)
Le biodiesel est un mélange d’esters mono-alkyl utilisé comme carburant alternatif au diesel. Il est obtenu par transestérification des huiles végétales ou de graisses animales par un alcool léger.L’objectif de ce travail consiste en la recherche de catalyseurs solides acides ou basiques capables de promouvoir la réaction de transestérification de l’huile de colza par l’éthanol en conditions aussi douces que celles utilisées en catalyse homogène basique. Pour cela, deux séries de solides acides et basiques ont été préparées et caractérisées par différentes techniques (ATG-ATD, DRX, Isotherme N2). Les propriétés acides et basiques de ces solides ont également été étudiées par calorimétrie et spectroscopie Infra Rouge. Des corrélations entre les activités initiales et les propriétés acides ou basiques de ces catalyseurs ont été recherchées. L’influence des principaux paramètres réactionnels a été examinée sur le catalyseur acide et le catalyseur basique, les plus actifs. Puis une étude cinétique comparative a été réalisée. Enfin la valorisation in situ du glycérol, produit secondaire de la réaction, a été considérée.Nous avons pu montrer que le sel de césium de l’acide 12-tungstophosphorique est le catalyseur acide le plus actif, dans la gamme de solides acides étudiés. Ceci s’explique par la présence de sites acides de BrØnsted forts aptes à promouvoir la réaction en conditions douces de température. Par ailleurs, il est capable de réaliser l’éthérification in situ du glycérol par l’éthanol. En catalyse basique, le nouveau catalyseur préparé, la zircone échangée au césium, est le catalyseur le plus actif parmi les bases solides étudiées. Ce catalyseur est stable dans le milieu réactionnel après élimination par lavage à chaud des espèces Cs labiles. La comparaison des deux catalyseurs montre que la catalyse basique est nettement plus rapide que la catalyse acide. L’étude cinétique permet de proposer des différences mécanistiques entre ces deux types de catalyseurs. / Biodiesel is a mixture of mono-alkyl esters used as alternative fuel. It can be obtained by transesterification of vegetable oils or animal fats with light alcohols.The objective of this work is the research of acid and basic solid catalysts able to promote the transesterification reaction of rapeseed oil with ethanol in conditions as mild as those used in homogeneous base catalysis. For this, two series of solid acids and bases were prepared and characterized by various characterization techniques (TGA-DTA, XRD, Isothermal N2). Calorimetry and Infrared Spectroscopy have also been used to characterize acid and basic properties. Correlations between initial activity and the acidic or basic properties of these catalysts have been investigated. The influence of the main reaction parameters was examined on the most active acid and basic solid. A comparative kinetic study then allowed us to propose reaction mechanisms. Finally the in situ valorisation of glycerol, a by product of the reaction, was carried out.We have shown that the cesium salt of 12-tungstophosphoric acid catalyst is the most active among the solid acids studied. This is explained by the presence of strong BrØnsted acid sites that are able to promote the reaction under mild temperature conditions. This catalyst is capable of achieving in situ etherification of glycerol with ethanol. In base catalysis, the newly prepared catalyst, zirconia exchanged with Cesium, is the most active catalyst among the solid bases studied. This catalyst is stable in the reaction medium after removal of the labile Cs species by hot washing. Comparison of the two catalysts shows that the base catalysis is much faster than acid catalysis. A kinetic comparative study allows us to propose mechanistic differences between these two types of catalysts.
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Avaliação das propriedades tribológicas de formulações compostas de óleos vegetais e polialquilenoglicóis aditivadas com ZDDP / Evaluation of tribological properties of vegetable oil based formulations contained polyalkyleneglycols and ZDDPOliveira, Clarissa Danielle Mendonça de 06 August 2013 (has links)
Os lubrificantes a base de óleo vegetal surgem como uma alternativa ao uso de lubrificantes minerais, em virtude da crescente busca pela preservação do meio ambiente. O presente trabalho avaliou o desempenho tribológico de óleos vegetais misturados a Polialquilenoglicóis (PAG) e os comparou com óleos minerais, sendo ambos, as misturas e os óleos minerais, classificados nos graus ISO 150 e 220. Foram testadas formulações de óleo de mamona + PAG (ISO 68), óleo de mamona + PAG (ISO 150), óleo de soja + PAG (ISO 680) e óleo de soja + PAG (ISO 680), nas proporções 65/32, 80/17, 50/47, 38/59, respectivamente, aditivadas com 3% de ZDDP, aditivo Extrema Pressão. Tais formulações foram previamente determinadas com base na viscosidade das misturas a 40°C. Foi traçado o perfil de viscosidade de todas as misturas e foram feitas análises de Ressonância Magnética Nuclear (RMN) e Calorimetria Diferencial Exploratória (DSC), para caracterização das mesmas. Além destas formulações, para efeito de comparação, foram testados óleos minerais ISO 150 e ISO 220, óleo de mamona puro e óleo de soja puro. O desempenho das formulações em relação ao atrito e ao desgaste foi avaliado por meio de ensaios de HFRR (High Frequency Reciprocating Rig), com carga de 10 N, frequência de 20 Hz e 60 minutos de duração, todos em duplicata. A temperatura do banho de óleo foi mantida em 50 ± 5°C. Os corpos-de-prova, de aço AISI 52100, foram analisados em Microscopia Eletrônica de Varredura (MEV) após cada ensaio. A formulação de óleo de mamona + PAG (150) + ZDDP apresentou os melhores desempenhos em termos de atrito e desgaste quando comparadas com o óleo mineral 220. / The biobased lubricants from vegetable oils arise as an alternative to the petroleum-based ones because of increasing search for the environment preservation. In this work, the tribological performance of vegetable oils with polyalkyleneglycols (PAG) was evaluated and compared with mineral oils. The vegetable oil and petroleum-based formulation are classified as ISO grades 150 and 220. Formulations were tested of castor oil + PAG (ISO 68), castor oil + PAG (ISO 150), soybean oils + PAG (ISO 680) and soybean oils + PAG (ISO 680), in the proportions 65/32/3, 80/17/3, 50 / 47/3, 38/59/3, respectively, and with 3% of ZDDP, an additive of extreme pressure. Such formulations were previously defined on the viscosity of the mixtures at 40° C. It was obtained the viscosity profile of the formulations and analysis were performed using 1H Nuclear Magnetic Resonance Spectroscopy (1H NMR) and Differential Scanning Calorimetry (DSC). Besides these formulations, petroleum-based formulations, ISO 150 and ISO 220, castor and soybean oil without any additive were analyzed to be compared with the biobased formulations. The performance of the formulations related to the friction and wear was evaluated through HFRR (High Frequency Reciprocating Rig) tests, with load of 10 N, frequency of 20 Hz and 60 minutes duration. Every test was made in duplicate. The oil bath temperature was maintained at 50 ± 5°C. The AISI 52100 steel specimens were analyzed by Scanning Electron Microscopy (SEM) after every test. The formulation of castor oil and PAG (150) + ZDDP showed the best performances in terms of friction and wear properties, when compared with the mineral oil ISO 220.
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Caracterização de óleos vegetais como alternativa para meios de resfriamento utilizados no tratamento térmico de têmpera / Characterization of vegetable oils as an alternative quenchants to heat treatmentFarah, Alessandro Fraga 17 December 2002 (has links)
No presente trabalho são relatados os resultados obtidos através de ensaios de caracterização de óleos de têmpera, tais como ponto de fulgor, viscosidade, número de acidez, espectroscopia por infravermelho e curvas de resfriamento, comparando óleos vegetais em estudo, com óleos minerais comerciais já utilizados como meios de resfriamento de têmpera. As curvas de resfriamento foram efetuadas utilizando sonda tipo Wolfson, nas temperaturas de 60, 80, 100 e 120ºC. Os ensaios de viscosidade foram feitos na temperatura de 40ºC. Adicionalmente, também foram efetuados ensaios de envelhecimento e oxidação dos óleos, utilizando um equipamento de envelhecimento acelerado, desenvolvido especialmente para este fim. De maneira geral, os óleos vegetais estudados apresentaram desempenho igual ou superior aos óleos minerais comerciais já utilizados em tratamentos térmico de têmpera. / In the present work are related the results obtained from the quenchant oils characterization test such as flash point, viscosity, acid number, infrared spectroscopy and cooling curves. In all tests the vegetables oils were compared with commercial quenchant mineral oils. Cooling curves were performed using Wolfson\'s probe at 60, 80, 100 and 120ºC. Viscosity tests were made in the temperature of 40ºC. Additional tests were performed for aging and oxidation studies, using an apparatus especially developed for that. In a general way, the vegetable oils have presented equal or best performance than the commercial quenchant mineral oils.
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Produção de Biodiesel a partir de óleos vegetais usando células íntegras imobilizadas de fungos filamentosos com elevada atividade lipolítica (Glicerol Éster Hodrolase - E.C.3.1.1.3) / Biodiesel production from vegetable oils using immobilized whole cells with high lipase activity (Glycerol Ester Hydrolase - E.C. 3.1.1.3)Andrade, Grazielle Santos Silva 01 March 2012 (has links)
O objetivo deste trabalho foi contribuir no desenvolvimento de técnicas para obtenção de biocatalisadores imobilizados de baixo custo e alto poder catalítico para ser empregado na síntese de biodiesel a partir de óleos vegetais pela rota etílica. Baseia-se na utilização de células íntegras de fungos filamentosos com elevada atividade lipolítica (glicerol éster hidrolase - E.C. 3.1.1.3) imobilizadas em suporte adequado. O trabalho experimental foi desenvolvido em diferentes etapas e iniciado pela triagem de linhagens de fungos adquiridas de banco de cultura nacional, com habilidade de produzir lipase intracelular em cultivo submerso. Mediante a avaliação da atividade lipolítica do micélio, foram selecionadas as linhagens dos fungos: Rhizopus oryzae (3231 e 4692), Mucor circinelloides (4140 e 4182) e Penicillium citrinum (4216) e efetuados testes de imobilização por adsorção física (in situ e extra-situ) da biomassa produzida, utilizando os seguintes suportes: espuma de poliuretano, Celite e polihidroxibutirato. Nas condições testadas, o melhor desempenho foi alcançado pela matriz de poliuretano que permitiu a retenção de elevada concentração de biomassa celular para todas as linhagens selecionadas, exceto para fungo de P.citrinum (4216). Testes adicionais de imobilização da biomassa celular na espuma de poliuretano foram efetuados, complementando desta forma, as propriedades físicas e morfológicas desse suporte e do sistema imobilizado. Os resultados indicaram que espumas de poliuretano cortadas em cubos de 6 mm foram mais adequadas para promover completa adsorção da biomassa celular produzida pelos fungos selecionados, em especial do fungo M. circinelloides 4182, que apresentou elevado poder catalítico na reação de transesterificação. Em virtude desse fato, as condições de cultivo dessa linhagem foram estudadas, mediante variação das fontes de carbono e nitrogênio, aeração e inóculo. O biocatalisador obtido nas melhores condições (atividade lipolítica= 65 U/g) foi utilizado na etanólise do óleo de babaçu e o processo foi otimizado por meio de um delineamento fatorial, avaliando-se a influência da temperatura (33 - 47C) e da razão molar entre óleo de babaçu e etanol (1:4,8 - 1:13,2) no rendimento de transesterificação. As condições otimizadas preditas pelo planejamento fatorial foram: temperatura de 35°C e razão molar etanol/óleo de 6:1, obtendo-se rendimento de 90,5% empregando 20% m/m de biocatalisador e terc-butanol como solvente. A estabilidade operacional do biocatalisador foi avaliada em reator operando em regime de bateladas consecutivas e em regime contínuo. Resultados satisfatórios foram obtidos em ambos os sistemas, entretanto o sistema contínuo evitou a dessorção do micélio do suporte, revelando tempo de meia-vida do biocatalisador superior a 20 dias. Finalmente, a influência de óleos vegetais contendo diferentes composições em ácidos graxos (andiroba, macaúba, pinhão manso e palma) foi avaliada na reação de etanólise, sendo constatado a preferência do biocatalisador na transesterificação de ácidos graxos de cadeia média, presentes nos óleos de babaçu e macaúba. De forma geral, os resultados obtidos foram promissores e demonstraram a potencialidade de células íntegras de fungos filamentosos imobilizadas na síntese de biodiesel, com destaque para o desempenho obtido pelo fungo Mucor circinelloides 4182. / The objective of this work was contributed in developing techniques to obtain immobilized biocatalysts with low cost and high catalytic activity to be applied in the biodiesel synthesis by ethanol route. It is based on the utilization of filamentous fungi whole cells with high lipase activity (glycerol ester hydrolase - E.C.3.1.1.3) immobilized in suitable support. The experimental work was developed in different ways and started by screening fungi strains acquired from National Culture Collection which has the ability to produce intracellular lipase in submerse cultivation. Through lipase activity the fungi strains: Rhizopus oryzae (3231 and 4692), Mucor circinelloides (4140 e 4182) and Penicillium citrinum (4216) were selected. Tests to evaluate the biomass immobilization by physical adsorption (in situ and extra-situ) using the supports: polyurethane foam, Celite and polyhidroxybutyrate were carried out. The best performance was attained by polyurethane matrix that allowed attain high biomass concentration for all strain fungi, except for P. citrinum (4216). Additional tests were performed to complement the physical and morphological properties of support and immobilized system. Results indicated that polyurethane foam cut in cubes 6-mm were suitable to provide full adsorption of biomass from all selected fungi strains, specially strain of M. circinelloides 4182 displayed high catalytic activity in the transesterification reaction. Consequently, cultivation conditions of this strain were studied, evaluating the carbon and nitrogen sources, aeration and inoculum level. The biocatalyst obtained under the best conditions (lipase activity = 65 U/g) was used in the ethanolysis of babassu oil and the process was optimized by experimental design. The influence of temperature (33 - 47?C) and ethanol to oil molar ratio (4.8:1 - 13.2:1) were investigated in the transesterification yield. Under the optimized conditions (35°C and oil to ethanol molar ratio 6:1) transesterification yield of 90.5% was obtained employing 20% wt. of biocatalyst and tert-butanol as solvent. The biocatalyst operational stability was assessed under consecutive batch runs and continuous system. Satisfactory results were attained in both systems, however, the continuous system avoided cells desorption from support, revealing biocatalyst half life higher than 20 days. Finally, the influence of vegetable oils with different fatty acid compositions (babassu, andiroba, macauba, Jatropha, palm) was studied in the ethanolysis reaction, being evidenced the specificity of the biocatalyst to transesterify medium chain fatty acids as presented in babassu and macauba oils. The results obtained were promise and demonstrated the potential of filamentous fungi whole cells immobilized as biocatalysts in the biodiesel synthesis, with prominence to the performance of Mucor circinelloides 4182 strain.
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