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Sustainable energy management has become a high priority for many countries. A great majority of our energy stocks comes from non-renewable fossil fuels, which are currently dwindling. Biofuels are one of the most promising solutions being researched to address this urgent problem. In particular, using transesterified Jatropha curcas L. oil appears to be a promising method of producing biofuels due to several properties of the plant, such as the high oil yield of its seeds and the fact that it does not compete with food crops. The literature mentions many attempts of using zeolites as solid acid catalysts in transesterification reactions of vegetable oils with high free fatty acid (FFA) content. The acid catalysis prevents soap formation and emulsification, which can be observed in the basic process. The use of a solid catalyst makes the separation and purification of the final products steps easier to implement in comparison to catalysis in homogeneous conditions. However, the efficiency of the zeolite in the heterogeneous transesterification reaction of vegetable oil is not well-known yet and varies on the structure of the catalyst used. This project aims at better understanding the relationship between the type of zeolite used and the yield of this particular reaction using reconstituted Jatropha oil from Sesame seed oil, which has a similar composition. Five different types of zeolites were compared: Y, X, Beta, Mordenite & ZSM-5. Non-catalyzed reactions as well as homogeneously catalyzed - with H2SO4 - reactions were also implemented. Since we take advantage of the catalytic properties of different zeolites, the one that were not already in hydrogen form were ion-exchanged and the ion-exchanged species were then analyzed by Energy-Dispersive X-Ray spectroscopy (EDX). Three alcohol-to-oil ratios were tested at atmospheric pressure and at T=115°C for each catalyst in order to determine the influence of this ratio. All experiments were conducted in an airtight autoclave with butan-1-ol in order to obtain a biofuel whose cetane index is higher than regular petroleum-based diesels.

O biodiesel substituto renovável do diesel convencional é quimicamente definido como ésteres monoalquílicos de ácidos graxos derivados de óleos vegetais e gorduras animais. O processo mais empregado para a sua produção é a transesterificação em meio alcalino. Este processo consiste em uma reação química na qual óleos vegetais e/ou gorduras animais reagem com um álcool de cadeia curta utilizando catalisador alcalino (usualmente hidróxido de potássio e metilato de sódio) resultando na mistura de ésteres monoalquílicos (biodiesel) e glicerina. O presente trabalho teve como objetivo avaliar o desempenho dos catalisadores alcalinos: metilato de sódio e hidróxido de potássio na produção de biodiesel pela rota metílica utilizando óleo de soja como fonte de triglicerídeo. A avaliação foi dividida em 3 partes: 1- Técnica: Qualidade do biodiesel, da glicerina gerada e a eficiência da conversão de óleo de soja em biodiesel. 2- Econômica: Custo de produção global do biodiesel. 3- Ambiental: Geração de resíduo quantitativa e qualitativa. A metodologia consistiu em realizar 3 bateladas com cada catalisador em um reator de vidro tipo batelada de 2.000 mL com circulação externa de água. Foi utilizado o mesmo óleo de soja refinado, metanol, procedimento experimental e metodologia analítica. Os resultados demonstraram que o catalisador metilato de sódio apresentou eficiência 4,8% superior ao hidróxido de potássio na conversão de óleo de soja em biodiesel, o custo de produção global teve redução de 3,2% (R$ 0,080/Kg de biodiesel produzido) e a geração de resíduo em volume foi reduzida em 9,8%. Ambos catalisadores apresentaram resultados dentro da especificação da resolução ANP no42. Estes resultados demonstram a grande vantagem do metilato de sódio frente ao hidróxido de sódio e exalta a importância da escolha do catalisador que oferece o melhor desempenho que é fundamental para a viabilidade técnica, financeira e ambiental do Programa Nacional de Produção de Biodiesel (PNPB). / Biodiesel is a renewable alternative to petroleum diesel fuel and is chemically defined as mono-alkyl esters of fatty acid derived of vegetable oils and animal fat. The most commonly used process in its production is alkaline transesterification. This process consists in a chemical reaction in which vegetable oil and/or animal fats react with a short chain alcohol, using an alkaline catalyst (usually potassium hydroxide and sodium methylate), resulting in a mixture of mono- alkyl esters (biodiesel) and glycerin. The objective of the present research is to evaluate the performance of alkaline catalysts: sodium methylate and potassium hydroxide in the production of biodiesel by the methylic route, using soybean as a triglyceride source. The evaluation was divided in 3 parts: 1 - Technical: biodiesel quality, generated glycerin quality and the soybean oil to biodiesel conversion efficiency. 2 - Economical: Biodiesel\'s global production cost. 3 - Environmental: Quantitative and qualitative waste generation. The methodology consisted in carrying through 3 (three) batches with each catalyst in a 2.000 mL batch type glass reactor with external water circulation. The same refined soybean, methanol, experimental procedure and analytical methodology were used. The results demonstrated that the sodium methylate catalyst presented an efficiency 4,8% higher than potassium hydroxide in the conversion of soybean into biodiesel, that the global production cost had a 3,2% reduction (R$ 0.08/Kg of produced biodiesel) and that waste generation in volume was reduced in 9,8%. Both catalysts presented results, within the specification of ANP no42 Ordinance. These results demonstrate the great advantage of sodium methylate in comparison to potassium hydroxide and exalts the importance of chossing the catalyst that offers the best performance that is necessary for the technical, financial and environmental viability of the National Biodiesel Production Program.

Soybean oil, palm oil and waste cooking oil as feedstock were used to measure the effects of different heating methods, reaction time, molar ratio of methanol to oil, temperature, power, catalyst type and catalyst concentration on the biodiesel yield in this study. Additionally, reducing reaction time for the transesterification reaction used microwave heating to make more complete. The optimized operating conditions of conventional heating used palm oil, concentration for 0.75 wt% sodium methoxide, molar ratio of methanol to oil for 6:1, reaction time for 90 min and reaction temperature for 60 ¢J offered the best yield of 98.1%. the microwave heating used palm oil, concentration for 0.75 wt% sodium methoxide, molar ratio of methanol to oil for 6:1, reaction time for 3 min and power for 750 W offered the best yield of 99.5% Used soybean oil and palm oil as biodiesel feedstock production, its yield was higher than the waste cooking oil. This reason is caused by composition complex and high viscosity of waste cooking oil compare with pure vegetable oil. The catalyst of sodium methoxide is higher effective than sodium oxide used in transesterification reaction, because the reaction process will not formation of water and saponification. Use ionic liquid [Pyr12CN][Cl], [MorEtH][HSO4], [MorMeMe][MeSO4], [PyrMeH][HSO4] and [MorMeEt][EtSO4] as biodiesel catalyst, the optimized operating conditions of concentration for 2.00 wt% [Pyr12CN][Cl], molar ratio of methanol to oil for 6:1, reaction time for 6 min and power for 750 W offered the best yield of 98.1%.

Chlorine gas bleaching was a common method used in pulp industries. As a consequence, significant amounts of chlorine were discharged into surrounding aquatic ecosystems, affecting the biota. Chlorinated organic pollutants are formed when chlorine react with organic material. Octadecanoic acid (stearic acid) is one of the most common saturated fatty acids in aquatic biota. In a naturally occurring process two and four chlorine atoms, respectively, are added over the unsaturated bonds, forming 9,10-dichloro octadecanoic acid and 9,10,12,13-tetrachloro octadecanoic acid. These are the chlorinated fatty acids (ClFA) under investigation in this Bachelor’s Thesis. The methodological framework for measuring ClFA is investigated in this essay. The scope is to evaluate the method of isolating and quantifying the compounds as described in Åkesson-Nilsson’s (2004) dissertation. The method includes: extraction of the lipid, transesterification (where the fatty acids, including the ClFAs, are separated from the lipids and transformed into their respective methyl esters through two methods, acidic catalysis with BF3 or H2SO4), separation (by solid phase extraction) and determination of ClFA concentration with a halogen specific detector (GC-XSD/MS). Furthermore, the scope is to investigate collected fish samples (from Norrsundet) with the abovementioned method. By making a dilution series with known concentrations it was possible to establish calibration curves, to give in an indication of the effectiveness of the method. BF3 is in need of updating due to being experienced as slower and less stable than the H2SO4-method. However, it was concluded that the H2SO4-method was more effective on the standard samples and that the BF3-method was more effective on the fish lipid samples. In one of the lipid samples (lavaret transesterified with BF3) a detectable concentration of 9,10,12,13-tetrachloro octadecanoic acid was discovered. Therefore, we question SEPAs decision to cancel investigations in Norrsundet. Our results could indicate that ClFAs are still an issue that could affect the ecosystem’s biota.

The production of biodiesel from a butter factory effluent was the main focus of the study. The alkali transesterification reaction was used to produce the biodiesel. The effect of the temperature, alcohol to oil molar ratio, catalyst concentration and the reaction time was investigated to determine the optimal reaction conditions. The reaction temperature varied from 45 °C to 65 °C with a 5 °C increment. The alcohol to oil molar ratio varied from 3:1 to 8:1 with an increment of 1:1. The experiments with varying catalyst load were carried out at 0.8 wt%, 1.0 wt% and 1.2wt%. The reaction time was kept constant at 120 minutes, but samples of the reaction mixture were taken at 10 minute intervals. The optimal reaction conditions according to the results were 50 °C, 6:1 alcohol to oil molar ratio, 1.0 to 1.2 wt% catalyst loads and a reaction time of 60 to 90 minutes. The optimal temperature was also the maximum temperature since a further increase in temperature lowered the ester content. Increasing the alcohol to oil molar ratio above 6:1 had no effect on the ester content. The increase in catalyst load decreased the time needed for the reaction to reach equilibrium. The purification process was also investigated. The biodiesel was washed with water, Magnesol® DSOLTM and Purolite® PD-206. The Magnesol® D-SOLTM was the best method for lowering the water content and the acid value of the fuel. A Magnesol® D-SOLTM content of 1.0 wt% was mixed with the biodiesel for 30 minutes in order to lower the water content and the acid value to below the maximum limit. A kinetic model for the biodiesel reaction was developed. The model was based on the second order reversible reaction. The temperature range for the model is from 45 °C to 55 °C. The forward reaction was found to be exothermic with an endothermic reverse reaction. The activation energy for the exothermic forward reaction varied between 9.478 and 26.937 kJ/mol while the activation energy for the endothermic reverse reaction varied between 74.161 and 136.433 kJ/mol for the reactions with a catalyst load of 1.2 wt%. The biodiesel was tested according to the SANS 1935:2011 standard. The biodiesel did not meet all the requirements of the standard. The flash point, sulphur content, carbon residue, oxidation stability, free glycerol, total glycerol and cold filter plugging point did not meet the specification of SANS 1935:2011. The biodiesel should be blended with mineral diesel if it is to be used commercially. The butter factory effluent can be used as a feedstock for the production of biodiesel. / Thesis (MIng (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013.

The production of biodiesel from a butter factory effluent was the main focus of the study. The alkali transesterification reaction was used to produce the biodiesel. The effect of the temperature, alcohol to oil molar ratio, catalyst concentration and the reaction time was investigated to determine the optimal reaction conditions. The reaction temperature varied from 45 °C to 65 °C with a 5 °C increment. The alcohol to oil molar ratio varied from 3:1 to 8:1 with an increment of 1:1. The experiments with varying catalyst load were carried out at 0.8 wt%, 1.0 wt% and 1.2wt%. The reaction time was kept constant at 120 minutes, but samples of the reaction mixture were taken at 10 minute intervals. The optimal reaction conditions according to the results were 50 °C, 6:1 alcohol to oil molar ratio, 1.0 to 1.2 wt% catalyst loads and a reaction time of 60 to 90 minutes. The optimal temperature was also the maximum temperature since a further increase in temperature lowered the ester content. Increasing the alcohol to oil molar ratio above 6:1 had no effect on the ester content. The increase in catalyst load decreased the time needed for the reaction to reach equilibrium. The purification process was also investigated. The biodiesel was washed with water, Magnesol® DSOLTM and Purolite® PD-206. The Magnesol® D-SOLTM was the best method for lowering the water content and the acid value of the fuel. A Magnesol® D-SOLTM content of 1.0 wt% was mixed with the biodiesel for 30 minutes in order to lower the water content and the acid value to below the maximum limit. A kinetic model for the biodiesel reaction was developed. The model was based on the second order reversible reaction. The temperature range for the model is from 45 °C to 55 °C. The forward reaction was found to be exothermic with an endothermic reverse reaction. The activation energy for the exothermic forward reaction varied between 9.478 and 26.937 kJ/mol while the activation energy for the endothermic reverse reaction varied between 74.161 and 136.433 kJ/mol for the reactions with a catalyst load of 1.2 wt%. The biodiesel was tested according to the SANS 1935:2011 standard. The biodiesel did not meet all the requirements of the standard. The flash point, sulphur content, carbon residue, oxidation stability, free glycerol, total glycerol and cold filter plugging point did not meet the specification of SANS 1935:2011. The biodiesel should be blended with mineral diesel if it is to be used commercially. The butter factory effluent can be used as a feedstock for the production of biodiesel. / Thesis (MIng (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013.

Heterogeneous catalytic reactions that involve immiscible liquid-phase reactants are challenging to conduct due to limitations associated with mass transport. Nevertheless, there are numerous reactions such as esterification, transesterification, etherification, and hydrolysis where two immiscible liquid reactants (such as polar and non-polar liquids) need to be brought into contact with a catalyst. With the intention of alleviating mass transport issues associated with such systems but affording the ability to separate the catalyst once the reaction is complete, the overall goal of this study is geared toward developing a catalyst that has emulsification properties as well as the ability to phase-transfer (from liquid-phase to solid-phase) while the reaction is ongoing and evaluating the effectiveness of such a catalytic process in a practical reaction. To elucidate this concept, the transesterification reaction was selected. Metal-alkoxides that possess acidic and basic properties (to catalyze the reaction), amphiphilic properties (to stabilize the alcohol/oil emulsion) and that can undergo condensation polymerization when heated (to separate as a solid subsequent to the completion of the reaction) were used to test the concept. Studies included elucidating the effect of metal sites and alkoxide sites and their concentration effects on transesterification reaction, effect of various metal alkoxide groups on the phase stability of the reactant system, and kinetic effects of the reaction system. The studies revealed that several transition-metal alkoxides, especially, titanium and yttrium based, responded positively to this reaction system. These alkoxides were able to be added to the reaction medium in liquid phase and were able to stabilize the alcohol/oil system. The alkoxides were selective to the transesterification reaction giving a range of ester yields (depending on the catalyst used). It was also observed that transition-metal alkoxides were able to be recovered in the form of their polymerized counterparts as a result of condensation polymerization subsequent to completion of the transesterification reaction.

Initially a comprehensive review on the production of biodiesel, as well as different types of catalysts used in the reactions and their respective routes, methyl or ethyl. Also during the review sought to demonstrate the cost effective use of biodiesel in conventional diesel grating, is the low emission of pollutants, is the simple fact is a renewable fuel, since the CO2 emitted during burning is absorbed again for oil seeds during all their lives, returning to produce more oils. Coconut oil had some advantages throughout the study, either by comparison of production between different oils, either because this has a culture that the intercropping system of planting. Leaving for the practice of biodiesel production, the initial step was the characterization of oil, by first determining the saponification number, where it was determined by the average molecular weight of used oil, then determined factors such as acid value, moisture and viscosity of the coconut oil used. After characterization, broke to the creation of 25 full factorial design with replicates, where due to operational problems reactions were carried 56 out of 64. Since the experiments were performed, it was possible to generate a graph comparing the experimental results obtained by the model and target as well as by analysis of variance proved the significance of the model. The analysis of response surfaces generated from the model served as a guide, directing where further work should follow ethanolysis with coconut oil. Finally, the study showed satisfactory results with approximately 100% yield and the determination of significant variables, which are the molar ratio and amount of catalyst as well as in obtaining a model that represents well the study process. / Inicialmente foi realizada uma extensa revisão bibliográfica sobre a produção de biodiesel, assim como os diferentes tipos de catalisadores empregados nas reações e suas respectivas rotas; metílica ou etílica. Ainda durante a revisão procurou-se mostrar o bom custo benefício do uso do biodiesel em ralação ao diesel convencional, seja pela baixa emissão de poluentes, seja pelo simples fato ser um combustível renovável, uma vez que o CO2 emitido durante sua queima é absorvido novamente pelas oleaginosas durante todas as suas vidas, voltando a produzir mais óleos. O óleo de coco apresentou algumas vantagens durante todo o estudo, seja pelos comparativos de produção entre diferentes óleos, seja pelo fato de apresentar um cultivo que permite o sistema consorciado de plantio. Partindo para a prática da produção de biodiesel, o passo inicial foi a caracterização do óleo, determinando o índice de saponificação, onde através dele determinou-se o peso molecular médio do óleo usado, em seguida determinou fatores como índice de acidez, umidade e a viscosidade do óleo de coco usado. Após a caracterização, partiu-se para a realização do planejamento fatorial completo 25 com repetição, onde devido a problemas operacionais foram realizados 56 reações de um total de 64. Uma vez que os experimentos foram realizados, os resultados possibilitaram a geração um gráfico comparativo entre os resultados experimentais e os obtidos pelo modelo alcançado, bem como através da análise de variância comprovou-se a elevada significância do modelo. A análise das superfícies de respostas geradas a partir do modelo serviu de guia, orientandopara onde devem seguir os futuros trabalhos com etanólise do óleo de coco. Por fim, o estudo se mostrou bastante satisfatório com resultados de aproximadamente 100 % de rendimento e a determinação das variáveis significantes, que são a razão molar e a quantidade de catalisador, bem como naobtenção de um modelo que represente bem o processo de estudo.

Made available in DSpace on 2016-06-02T19:56:58Z (GMT). No. of bitstreams: 1 6661.pdf: 7538464 bytes, checksum: 48b2c202273cc209a796ea8ef2da1b35 (MD5) Previous issue date: 2015-02-23 / Universidade Federal de Sao Carlos / In recent years there has been growing interest in studies on the use of heterogeneous catalysts in the biodiesel production, since such materials have some advantages over homogeneous catalysts such as ease of separation of product generated and the possibility of being reused. Among these catalysts, it is important to emphasize the mesoporous molecular sieves, since they have some advantages that enable its catalytic application. This study aimed to synthesize spheres of hybrid silica, with mesoporous occluded by the driver structure (CTA-SiO2), and to investigate the influence of different alcohols in the properties of these materials and evaluate their catalytic activity in the transesterification reaction. The mesoporous silicas were synthesized with varying the length of the alkyl chain (C1-C3) and amount of alcohol in the reaction mixture. The silicas were characterized by different techniques, such as X-ray scattering at small angles (SAXS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermogravimetric analysis. The results showed that the structure and morphology of the mesoporous silica containing organic driver may be controlled during synthesis by varying alcohol content, leading to the formation of materials with different phases, levels of organization and morphology, with the best results obtained from the samples synthesized with methanol and ethanol. For the evaluation of activity and catalytic stability, hybrid silicas were tested in transesterification reaction between ethyl acetate and methanol. The materials showed activity, and when the pore structure is well organized, larger amount of catalytic sites is available resulting in higher conversions. Thus synthesized materials with lower amounts of alcohol had higher catalytic activity compared with other materials. Silicas synthesized showed little catalytic stability compared to successive uses in the transesterification reaction. Thus, materials synthesized with the use of smaller amounts of alcohol tended to stability in comparison to other samples. Part of the activity is due to the presence of basic species formed as a result of leaching of cations CTA+, promoting the reaction also in the homogeneous phase. / Nos últimos anos tem sido crescente o interesse por estudos sobre o emprego de catalisadores heterogêneos na produção de biodiesel, uma vez que esses materiais possuem algumas vantagens em relação à catálise homogênea, tais como a facilidade de separação dos produtos gerados e possibilidade de serem reutilizados. Dentre esses catalisadores, torna-se importante salientar as peneiras moleculares mesoporosas, pois apresentam algumas vantagens que viabilizam sua aplicação catalítica. O presente estudo teve como objetivo sintetizar sílicas híbridas em formato de esferas, com mesoporos ocluídos pelo direcionador de estrutura (CTA-SiO2), bem como investigar a influência de diferentes álcoois nas propriedades desses materiais e avaliar sua atividade catalítica na reação de transesterificação. As sílicas mesoporosas foram sintetizadas com variação do comprimento da cadeia alquílica (C1-C3) e quantidade de álcool na mistura reacional. Foram caracterizadas por diferentes técnicas, como: espalhamento de raios X a ângulos pequenos (SAXS), difratometria de raios- X (DRX), microscopia eletrônica de varredura (MEV), microscopia eletrônica de transmissão (MET) e análise termogravimétrica. Os resultados mostraram que a estrutura e morfologia das sílicas mesoporosas contendo direcionador orgânico podem ser controladas durante a síntese através da variação do teor de álcool, levando à formação de materiais com diferentes fases, níveis de organização e morfologia, sendo os melhores resultados obtidos a partir das amostras sintetizadas com metanol e etanol. Para avaliação da atividade e a estabilidade catalítica, as sílicas híbridas foram testadas na reação de transesterificação entre o acetato de etila e metanol. Os materiais apresentaram atividade, sendo que quando a estrutura dos poros é bem organizada, maior quantidade de sítios catalíticos fica disponível resultando em maiores conversões. Consequentemente, os materiais sintetizados com menores teores de álcool apresentaram maior atividade catalítica em comparação com os demais materiais. As sílicas sintetizadas mostraram pouca estabilidade catalítica frente a sucessivos usos na reação de transesterificação. Assim, os materiais sintetizados com emprego de menores teores de álcool apresentaram uma tendência à estabilidade em relação às demais amostras. Parte da atividade se deve à presença de espécies básicas formadas em consequência da lixiviação dos cátions CTA+, promovendo a reação também na fase homogênea.