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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.
121

Développement d'un procédé de production de biodiesel de troisième génération à partir d'un déchet organique issu de l'agro-industrie réunionnaise : la vinasse de distillerie / Biotechnological valuation for distillery slops as biodiesel

Hoarau, Julien 20 September 2016 (has links)
La Réunion dispose d'un gisement important de ressources organiques renouvelables dont une grande partie est sous forme de déchets liquides tels que les vinasses de distillerie, représentant plus de 150 000 tonnes d'effluent par an. Les problématiques de gestion de ces effluents sont fortement impactées par leur haute charge en élément organique et nécessitent la mise en œuvre de techniques de dépollution coûteuses. Leur valorisation en tant que matière première est donc une voie potentielle pour une gestion plus efficace et économiquement rentable. Parmi les nombreuses pistes de valorisation biotechnologiques existantes pour les vinasses de distillerie, nous nous sommes proposés dans ce projet de valoriser ces déchets sous forme de biodiesel. La sélection de microorganismes oléagineux (champignons filamenteux et levures) adaptés aux déchets liquides de distilleries locales en vue de leur transformation en biodiesel a mis en avant les capacités de croissance des souches de champignons filamenteux dont 60% de celles testées ont démontré une croissance supérieure à 8 g/L et allant jusqu’à 20 g/L, avec des capacités de mobilisation des ressources nutritives de la vinasse jusqu’à 50% de l'azote et du carbone organique. L'adaptation du procédé à la levure oléagineuse Yarrowia lipolytica, connue comme microorganisme oléagineux modèle pour la production de biodiesel a mis en évidence une carence en phosphate limitante pour la croissance de ce microorganisme, ainsi qu'une amélioration de 80% de la biomasse produite observée après ajout de KH2PO4. Par ailleurs, la mobilisation du matériel enzymatique d'un microorganisme à forte croissance sur vinasse a également permis d'obtenir une amélioration de la production de biomasse levurienne, laissant entrevoir la possibilité de valorisation d'un cocktail enzymatique spécifiquement adapté à la dégradation de vinasses de distilleries. Enfin, l'évaluation de protocoles de transformation des lipides plus efficaces a été réalisée en cherchant à limiter les coûts liés au séchage et à l'extraction des lipides avant méthanolyse. L'application de la transestérification directe de la biomasse a permis une production plus importante de biodiesel comprise entre 10 et 90 % selon l'humidité de la biomasse, démontrant la possibilité de supprimer l'étape d'extraction des lipides. Par ailleurs, la combinaison de catalyseurs basiques et acides permet d'augmenter les rendements en biodiesel à partir de biomasse humide pour se rapprocher des performances obtenues sur biomasse sèche. / Reunion Island offers an important source of renewable organic resources, much of which is in liquid waste such as distillery slops, representing more than 150 000 tons of effluent annually. The management issues of these effluent are strongly affected by their high load of organic element and require implementation of expensive decontamination techniques. Their value as raw material is thus a potential route for more efficient and cost-effective management. Among the many tracks of biotechnological valuation existing for distillery slops, this project focus on enhancing these wastes as biodiesel. The selection of oleaginous microorganisms (molds and yeasts) suitable for liquid waste of local distilleries for further processing into biodiesel have demonstrated the high growth ability of filamentous fungi with 60% of tested strains offering higher growth than 8 g/L and up to 20 g/L, with nutrient resource mobilization capacities from vinasse up to 50% of the nitrogen and organic carbon. Adapting the process to the oleaginous yeast Yarrowia lipolytica, known as oleaginous microorganism model for biodiesel production highlighted a phosphate deficiency limiting for the growth of this microorganism with 80% improvement observed when KH2PO4 was fed. Furthermore, the mobilization of the enzymatic equipment of a high growing microorganism on vinasse has also yielded improved biomass production, raising the possibility of recovery of an enzymatic cocktail specifically adapted to the degradation of distillery slops. Finally, the evaluation of more effective lipid transformation protocols was conducted in seeking to limit the costs for drying and lipid extraction prior to methanolysis. The application of the direct transesterification of biomass has increased production of biodiesel between 10 and 90% depending on the moisture of biomass, demonstrating the ability to remove lipid extraction step. Furthermore, the combination of basic and acidic catalysts can increase biodiesel yields from wet biomass to reach performance close to dry biomass.
122

Etude de la réaction de transestérification des huiles végétales catalysés par les liquides ioniques en milieu CO2 supercritique / Study of the transesterification reaction of vegetable oil catalysed by different acid ionic liquids in supercritical CO2 medium

Dang, Kim Hoang 09 September 2010 (has links)
Le biodiesel, provenant de sources renouvelables, devient de plus en plus intéressant pour des raisons environnementales et à cause de la perspective de la pénurie des carburants fossiles. La méthode principale pour la production de biodiesel est la réaction de transestérification de l'huile végétale catalysée par des catalyseurs acides, basiques ou enzymatiques en phase homogène ou hétérogène. Le but de ce travail est d'étudier une nouvelle voie de production de biodiesel à partir de l'huile de colza en utilisant un liquide ionique comme catalyseur et le CO2 supercritique comme milieu réactionnel. Les liquides ioniques fonctionnalisés sulfoniques sont des liquides ioniques acides possédant de bonnes propriétés catalytiques pour la transestérification de l'huile. Le caractère lipophile du liquide ionique ainsi que l'alcool influence la performance de la réaction. L'éthanol et le 1-propanol sont plus réactifs que le méthanol à cause de leur meilleure solubilité dans l'huile. Le liquide ionique peut être recyclé et la séparation des esters d'acides gras a lieu par simple décantation. L'effet du CO2 sur la transestérification de l'huile de colza catalysée par les liquides ioniques n'est pas clairement positif à cause de l'extraction préférentielle de l'éthanol. Cependant, en rajoutant l'éthanol en continu, l'influence du CO2 devrait être plus favorable. Le CO2 pourra être également utilisé en fin de réaction comme solvant permettant de séparer des esters, du glycérol et du catalyseur. / Biodiesel, resulting from renewable sources, becomes more and more interesting for environmental reasons and because of the perspective of the shortage of fossil fuels. The main method for the production of biodiesel is the reaction of transesterification of vegetable oil catalyzed by acid, basic or enzymatic catalysts in homogeneous or heterogeneous phase. The purpose of this work is to study a new way of biodiesel production from the rapeseed oil by using an ionic liquid as catalyst and supercritical CO2 as reaction media. The HSO3 functionalized ionic liquids are acid ionic liquid possessing good catalytic properties for the oil transestefication. The lipophilic character of ionic liquid as well as alcohol influences the performance of the reaction. Ethanol and 1-propanol are more reactive than methanol because of their best solubility in the oil. The ionic liquid can be recycled and the separation of the esters of fatty acids takes place by simple settling. The effect of CO2 on the transesterification of rapeseed oil catalyzed by ionic liquids is not clearly positive because of the preferential extraction of the ethanol. However, by adding the ethanol continuously, the influence of CO2 should be more favorable. Supercritical CO2 can be also used to separate esters, glycerol and catalyst at the end of reaction.
123

Production of Biodiesel from Soybean Oil Using Supercritical Methanol

Deshpande, Shriyash Rajendra 10 March 2016 (has links)
The slow yet steady expansion of the global economies, has led to an increased demand for energy and fuel, which would eventually lead to shortage of fossil fuel resources in the near future. Consequently, researchers have been investigating other fuels like biodiesel. Biodiesel refers to the monoalkyl esters which can be derived from a wide range of sources like vegetable oils, animal fats, algae lipids and waste greases. Currently, biodiesel is largely produced by the conventional route, using an acid, a base or an enzyme catalyst. Drawbacks associated with this route result in higher production costs and longer processing times. Conversely, supercritical transesterification presents several advantages over conventional transesterification, such as, faster reaction rates, catalyst free reaction, less product purification steps and higher yields. This work focused on the supercritical transesterification of cooking oil, soybean in particular. The experimental investigation was conducted using methanol at supercritical conditions. These conditions were milder in terms of pressure than those reported in literature. A batch setup was designed, built and used to carry out the supercritical transesterification reactions. The biodiesel content was analyzed using gas chromatography-mass spectrometry to calculate reaction yields. Methyl ester yield of 90% was achieved within 10 minutes of reaction time using supercritical transesterification. A maximum yield of 97% was achieved with this process in 50 minutes of reaction time. Two key factors, temperature and molar ratio were studied using variance analysis and linear regression and their significance on the biodiesel yield was determined. The kinetic tendency of the reaction was investigated and the values of rate constants, activation energy and the pre-exponential factor were estimated.
124

Síntese de biodiesel a partir de óleo de mamona empregando etanol subcrítico / Synthesis of biodiesel from castor oil using subcritical ethanol

Rodríguez Guerrero, Julie Katerine, 1984- 18 August 2018 (has links)
Orientadores: Rubens Maciel Filho, Paulo de Tarso Vieira e Rosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-18T13:48:41Z (GMT). No. of bitstreams: 1 RodriguezGuerrero_JulieKaterine_M.pdf: 4744317 bytes, checksum: 8df1bde5d893cdf55d7e26d1c72fc31d (MD5) Previous issue date: 2011 / Resumo: Neste trabalho, foram estudados três processos de síntese de ésteres etílicos: sem catalisador, com catalisador homogêneo (hidróxido de sódio) e com catalisador heterogêneo (difosfato ácido de lantânio), a partir de óleo de mamona em etanol sub e supercrítico. O estudo da influência das variáveis de operação na conversão nos processos não catalítico e usando catalisador homogêneo foi realizado por meio de planejamento experimental associado à metodologia de superfície de resposta, utilizando como variáveis independentes a temperatura, o tempo de reação, a razão molar etanol:óleo e, quando utilizado, a concentração de catalisador. No caso do processo com catalisador heterogêneo, foram feitas análises nas condições ótimas (temperatura e razão molar) determinadas a partir do planejamento experimental dos outros dois processos. Verificou-se que, usando 0,1 % m/m de NaOH (quantidade inferior à necessária para neutralizar o óleo), foi possível obter conversões elevadas e que o uso de difosfato ácido de lantânio apresenta uma atividade catalítica significante na produção de biodiesel, mesmo utilizando óleos com índice de acidez alto. A máxima conversão atingida foi 98,94 % no processo com catalisador homogêneo, 92,94 % no processo com catalisador heterogêneo e 56,17 % no processo não catalítico. Além disso, foi obtida a cinética das reações e as energias de ativação para os três processos, observando-se que as constantes de reação são de pseudo primeira ordem. As energias de ativação encontram-se dentro da faixa reportada na literatura. Além disso, verificou-se que, a opção de trabalhar com NaOH é a mais viável em termos operacionais, já que o custo do catalisador é baixo, a quantidade de catalisador empregada é pequena e, adicionalmente, não requer uma etapa de pré-tratamento do óleo de mamona usado como matéria-prima / Abstract: In this work, three processes of synthesis of ethyl esters were studied: non-catalytic, using homogeneous catalyst (sodium hydroxide) and using heterogeneous catalyst (acid lanthanum diphosphate), from castor oil and sub and supercritical ethanol. The influence of the operating variables on the conversion of both non-catalytic and using homogeneous catalyst processes was studied by means of a design of experiment associated to the surface response methodology, using temperature, reaction time, ethanol:oil molar ratio and, whenever used, catalyst concentration as independent variables. In the process with heterogeneous catalyst, several analysis were performed under the optimum conditions (temperature and molar ratio) calculated from experimental design of the other two processes. It was verified that, using 0,1% wt of NaOH (amount lower than the required to neutralize the oil), it was possible to obtain high conversions and that using acid lanthanum diphosphate presents a significant catalytic activity on the biodiesel production, even using oils with high acidity index. The maximum conversion reached was 98,94 % in the process with homogeneous catalyst, 92,94 % with heterogeneous catalyst and 56,17 % in the non-catalytic process. Additionally, the reaction kinetics and activation energies were obtained for the three processes, observing that the reaction rate constants are pseudo first order. The activation energies are within the range reported on literature. Besides, it was verified that the option of working with NaOH is the most interesting in operational terms since the catalyst cost is low, the amount of catalyst used is small and, in addition, it is not necessary a pretreatment stage of the castor oil used as raw material / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
125

Examining the use of Simarouba glauca Seed Oil as a Feedstock for the Production of Biodiesel using a Small Scale Model Developed in India

Jungman, Andrew Aaron 06 November 2012 (has links)
Simarouba glauca, a non-edible oilseed crop native to South Florida, is gaining popularity as a feedstock for the production of biodiesel. The University of Agriculture Sciences in Bangalore, India has developed a biodiesel production model based on the principles of decentralization, small scales, and multiple fuel sources. Success of such a program depends on conversion efficiencies at multiple stages. The conversion efficiency of the field-level, decentralized production model was compared with the in-laboratory conversion efficiency benchmark. The study indicated that the field-level model conversion efficiency was less than that of the lab-scale set up. The fuel qualities and characteristics of the Simarouba glauca biodiesel were tested and found to be the standards required for fuel designation. However, this research suggests that for Simarouba glauca to be widely accepted as a biodiesel feedstock further investigation is still required.
126

Síntese enzimática de peptídeos contendo asparagina e transesterificação de seus ésteres de peptídeos na presença de Ca(II) / Enzymatics synthesis of peptides containing asparagine and transesterification it esters of peptides in the presence of CA (II)

Maria Teresa Machini de Miranda 19 September 1989 (has links)
Visando dar continuidade ao estudo de incorporação de N-acil-asparagina a derivados de aminoácidos e a peptídeos mediante catálise por termolisina, foi estudada a viabilidade de síntese dos peptídeos Z-Asn-Cys(S-Bzl)-OBut e Moz-Asn-Cys(S-Bzl)-Pro-Leu-Gly-NH2. Durante a síntese do pentapeptídeo Moz-Asn-Cys(S-Bzl)-Pro-Leu-Gly-NH2 foi constatada a formação de um subproduto cuja estrutura foi elucidada a partir da comparação ao padrão autêntico Moz-Asn-Leu-Gly-NH2. Para a obtenção deste padrão, sintetizamos o tripeptídeo Moz-Asn-Leu-Gly-OEt a partir de Moz-Asn-OH e H-Leu-Gly-OEt na presença de termolisina. A recristalização deste peptídeo em MeOH/H2 O levou à transformação do mesmo em Moz-Asn-Leu-Gly-OMe, confirmada pelo isolamento e caracterização do produto por espectrometria de massa e ressonância magnética protônica, análise elementar e de aminoácidos e por determinação do tempo de retenção por HPLC. Estudos posteriores demonstraram o envolvimento do íon Ca(II) no processo e nos permitiram sugerir um modelo da ligação deste íon ao peptídeo e da sequência de reação da transesterificação estudada. Também foi investigada a possibilidade de diversos ésteres de peptídeos e de peptidilresinas de Merrifield sofrerem transesterificação quando incubados em metanol na presença de Ca(II). Para tanto, os tripeptídeos Z-Asn-Leu-Gly-OEt, Boc-Asn-Leu-Gly-OEt, Moz-Asn-Leu-Gly-OBzl, Moz-Asn-Leu-Gly-OBu Moz-Gln-Leu-Gly-OEt, Moz-Asn-Ile-Gly-OEt e Moz-Asn-Leu-Ala-OEt foram sintetizados mediante catálise por termolisina. Também foram testados vários outros peptídeos disponíveis no laboratório e Boc-Leu-Gly-Res e Moz-Asn-Leu-Gly-Res. Com exceção dos ésteres terc-butílicos, todos sofreram transesterificação em soluções metanólicas de acetato de cálcio. / The main obJective was the study of thermolysin catalyzed incorporation of N-acyl-asparagine into amino acid and peptide derivatives. Both Z-Asn-Cys(S-Bzl)-OBut and Moz-Asn-Cys(S-Bzl)-Pro-Leu-Gly-NH2 syntheses have been studied. The formation of a by-product occurred during the synthesis of the later pentapeptide. By comparison with an authentic standard this by-product was identified as Moz-Asn-Leu-Gly-NH2. The standard Moz-Asn-Leu-Gly-NH2 was obtained by aminolYSlS of Moz-Asn-Leu-Gly-OEt. This peptide was synthesized by coupling Moz-Asn-OH with H-Leu-Gly-OEt using thermolysin as catalyst. During the recrystallization in MeOH/H2O, the transformation of Moz-Asn-Leu-Gly-OEt to its methyl-ester was obtained. This observation has been confirmed by purification and caracterization of the peptide by: Mass Spectroscopy, Nuclear Magnetic Ressonance, Amino Acid and Elemental Analysis and HPLC. Later studies have shown that the Ca(II) ion participates in the process. A model for the binding of this ion to the peptide and for the transesterification reaction has been suggested. Further studies have been performed with (1) the newly synthesized peptides Z-Asn-Leu-Gly-OEt, Boc-Asn-Leu-Gly-OEt, Moz-Asn-Leu-Gly-OBzl, Moz-Asn-Leu-Gly-OBut, Moz-Gln-Leu-Gly-OEt, Moz- Asn-Ile-Gly-OEt and Moz-Asn-Leu-Ala-OEt; (2) several other peptides available in our laboratory; and (3) Boc-Leu-Gly-Res and Moz-Asn-Leu-Gly-Res. With the exception of t-butyl-esters, all peptides tested have transesterified in methanolic calcium acetate solutions.
127

PRODUÇÃO DE BIODIESEL E SABÃO A PARTIR DE ÓLEOS RESIDUAIS NA REGIÃO DE MACHADO - MG. / BIODIESEL AND SOAP PRODUCTION FROM RESIDUAL OIL IN THE REGION OF MACHADO MG

Leite, Vera Lúcia Araújo 18 May 2010 (has links)
Made available in DSpace on 2016-05-02T13:54:03Z (GMT). No. of bitstreams: 1 VeraLuciaAraujoLeite-Dissertacao.pdf: 357600 bytes, checksum: e05515ee67ae627974704720e986db8b (MD5) Previous issue date: 2010-05-18 / The present study aimed at testing the possibility of using residual oil in biodiesel production, thus reducing the amount of this oil that is released daily in the sewer system and causes much of water pollution. Five treatments were carried through in laboratory procedures. They consisted of biodiesel production with refined soybean oil by methyl and ethylic route; biodiesel production from waste oil by ethylic route with water addition at the end of the transesterification process; biodiesel production from washed residual oil, by alcoholic route, with or without water addition at the end of the transesterification process. The biodiesel production was also tested at the plant with refined soybean oil and residual oil. Laboratory results have shown that the biodiesel production using non-residual oil, by methyl route, has the same yield of the ethylic route. The use of washed residual oil with water addition at the end of the process allows the production of biodiesel with visual quality similar to that of non-residual oil obtained through laboratory procedures and with return 5% lower than non-residual oil. The yield of biodiesel at the plant was around 80% for residual or non-residual, indicating that biodiesel yield may be lower in large-scale production than in laboratory production processes, getting an average production of 300 liters of biodiesel for each 300 liters of vegetable oil. / O presente trabalho teve como objetivo testar a possibilidade do uso do óleo residual a produção de biodiesel, reduzindo assim a quantidade deste óleo que é lançada diariamente na rede de esgoto e causa grande parte da poluição dos recursos hídricos. Nos procedimentos laboratoriais foram realizados cinco tratamentos, os quais contaram da produção de biodiesel com uso de óleo refinado de soja pela rota etílica e metílica; produção de biodiesel a partir de óleo residual pela rota etílica com água adicionada no final do processo de transesterificação; obtenção de biodiesel com óleo residual lavado, pela rota etílica, com ou sem água adicionada no final do processo de transesterificação. Foi também testada a produção de biodiesel na usina com óleo refinado de soja e com óleo residual. Os resultados laboratoriais demonstraram que a produção de biodiesel, utilizando o óleo não residual, pela rota metílica, apresenta o mesmo rendimento da rota etílica. A utilização de óleo residual lavado e com adição de água ao final do processo permite produção de biodiesel com qualidade visual semelhante à do óleo não residual através dos procedimentos laboratoriais e com rendimento 5% inferior quando comparado com o óleo não residual. O rendimento de biodiesel na usina foi em torno de 80% para o residual ou não residual, demonstrando que em larga escala o rendimento de biodiesel pode ser inferior aos obtidos nos processos laboratoriais, sendo obtida uma produção média de 300 litros de biodiesel para cada 300 litros de óleo vegetal.
128

CRIAÇÃO DE CD MULTIMÍDIA ENFOCANDO CONCEITOS E PROCESSOS PRODUTIVOS DE BIODIESEL NO BRASIL. MG / CREATION OF MULTIMEDIA CD FOCUSING ON BIODIESEL CONCEPTS AND PRODUCTION PROCESSES IN MINAS GERAIS, BRAZIL

Maciel, Hagar Ceriane Costa Corsini 22 June 2010 (has links)
Made available in DSpace on 2016-05-02T13:54:07Z (GMT). No. of bitstreams: 1 HagarCerianeCCMaciel-dissertacao.pdf: 2146542 bytes, checksum: 24e7212283892f7fa9975fae60669ed9 (MD5) Previous issue date: 2010-06-22 / With the current major development in computer science, new methodologies have been used to improve the process of information dissemination. A perspective that cannot be ignored is the question of how to use these technologies to improve the teaching and learning process. One of these methodologies is the multimedia. This study, conducted in the laboratories of the Federal Institute of Informatics Sul de Minas, Campus Machado, MG, and in the José Rosário Vellano University, Campus Alfenas, MG, aims at demonstrating that the use of multimedia techniques, in parallel with all the resources it aggregates, may be a usefull and efficient tool, planned and developed to be a practical source of information collected in a sigle application of study on biodiesel. The Menu strategy, was used for navigation, where one chooses the option of acessing the contents without having to obey any predetermined order. Thus the users will free to access the contents in a dynamic, interactive and pleasant way, according to their interest or need, using audiovisual resources of easy operation and assimilation. The software was available for some students and teachers to evaluate the usability, readability, learning, teaching, multimedia elements, layout and interactivity. In general the software was assessed and satisfactorily met the user s expectations. In a scale of 2-10 points, for all variables studied, the average was above than 8.5 points. The CD-ROM of the biodiesel multimedia is a didactic material developed for educators and high school and college students. / Atualmente, com a grande evolução na informática, novas metodologias vêm sendo utilizadas para melhorar o processo de disseminação das informações. Uma perspectiva que não pode mais ser ignorada é a questão de como utilizar tais tecnologias para melhorar os processos de ensino e aprendizagem. Uma dessas metodologias é o que se chama de multimídia. O presente trabalho pretende demonstrar que a utilização de técnicas multimídia, paralelamente com todos os recursos a ela agregados, poderá ser uma ferramenta útil, eficaz, que foi planejada e desenvolvida para ser uma fonte prática de informações reunidas em uma única aplicação de estudo sobre o tema Biodiesel. O trabalho foi desenvolvido nos Laboratórios de Informática do Instituto Federal Sul de Minas , campus Machado MG, e da Universidade José do Rosário Vellano, campus Alfenas MG. Para navegação foi usada a estratégia de Menu, onde se escolhe a opção de acessar o conteúdo, não obedecendo a nenhuma ordem pré-determinada. Com isso os usuários não se sentirão aprisionados, pois o conteúdo é acessado de forma dinâmica, interativa e prazerosa, de acordo com o seu interesse ou necessidade, utilizando-se de recursos audiovisuais, de fácil operação e assimilação. O software foi disponibilizado para alguns alunos e professores para avaliação quanto à usabilidade, legibilidade, aprendizado, didática, elementos multimídia, leiaute e interatividade. De maneira geral, o software foi avaliado satisfatoriamente e atendeu às expectativas dos usuários. Em uma escala de notas de 2 a 10 pontos, para todas as variáveis estudadas, a média foi superior a 8,5 pontos. O CD-ROM do multimídia Biodiesel é material didático para educadores e alunos do ensino médio e superior.
129

Reação de esterificação entre glicerol e ácidos graxos como subsídio para transesterificação de lipídeos / Fatty acids and glycerol esterification as basis for lipid transesterification

Luiz Antonio Gioielli 13 November 1979 (has links)
Não consta resumo na publicação. / Abstract not available.
130

Production of biodiesel from sunflower oil and ethanol by base catalyzed transesterification / Produktion av biodiesel från solrosolja  och etanol genom baskatalyserad omförestring

Sales, Alejandro January 2011 (has links)
Biodiesel is an attractive alternative fuel for diesel engines.The feedstock for biodiesel production is usually vegetable oil, pure oil or waste cooking oil, or animal fats The most common way today to produce biodiesel is by transesterification of the oils with an alcohol in the presence of an alkaline catalyst. It is a low temperature and low-pressure reaction. It yields high conversion (96%-98%) with minimal side reactions and short reaction time. It is a direct conversion to biodiesel with no intermediate compounds. This work provides an overview concerning biodiesel production. Likewise, this work focuses on the commercial production of biodiesel. The Valdescorriel Biodiesel plant, located in Zamora (Spain), is taken like model of reference to study the profitability and economics of a biodiesel plant. The Valdescorriel Biodiesel plant has a nominal production capacity of 20000 biodiesel tons per year. The initial investment for the biodiesel plant construction is the 4.5 millions €. The benefits are 2 million €/year. The investment is possible to recuperate in less than 3 years. The biodiesel yield can up to 98% with catalyst in excess. The energy used for the biodiesel production is 30% less than the obtained energy from the produced biodiesel. Replacing petro diesel by the biodiesel produced in the plant, the CO2 reduction can reach the 48%. It means that 55 000 tons CO2 per year can be reduced The production of biodiesel from sunflower oil and ethanol using sodium hydroxide as catalyst was performed in the laboratory and the results are discussed. The results are analyzed using the statistic method of Total Quality. The effect of the ethanol/oil ratio and the amount of used catalyst on the yield as well on the properties of the produced biodiesel is studied. The measured properties of the biodiesel are density, viscosity and refraction. The ethanol/oil ratio influences on the biodiesel production. The yield of biodiesel increases with the ethanol/oil ratio.  Regarding the influence of the amount of catalyst on biodiesel production in the studied condition is not possible to achieve a definitive conclusion. But a tendency showing an increasing of the biodiesel yield with the amount of catalyst can be appreciated. The study of the evolution of the transesterification during time shows that a reaction time of one hour is sufficient enough in order to reach the highest yield of biodiesel.

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