O presente trabalho teve como objetivo estudar a síntese do biodiesel por transesterificação etílica de diferentes matérias-primas lipídicas empregando catalisadores heterogêneos (químico e bioquímico). Para cumprir com os objetivos propostos foram selecionadas matérias-primas lipídicas de baixo impacto no setor alimentício, entre as quais destacam-se: óleos vegetais (andiroba, babaçu, macaúba, palma e pinhão manso) e gordura residual (sebo bovino) e catalisadores de comprovada potencialidade como óxido de nióbio impregnado com sódio (químico) e a lipase de Burkholderia cepacia imobilizada em suporte híbrido sílicaalcool polivinílico (bioquímico). O trabalho foi desenvolvido em três etapas. Inicialmente, foram determinadas as propriedades físico-químicas das diferentes matérias-primas lipídicas, algumas ainda pouco exploradas, para verificar se apresentavam potencial para serem utilizadas na reação de transesterificação. Em seguida foram preparados os catalisadores propostos por protocolos já estabelecidos, sendo obtido para o catalisador químico elevado teor de sódio impregnado no óxido de nióbio (25,43 ± 0,29%) e para catalisador bioquímico elevada atividade hidrolítica (1814 ??281 U/g). Na segunda etapa, as reações de transesterificação foram conduzidas em regime de batelada em condições adequadas para cada catalisador em termos de temperatura, tempo e proporção de catalisador. Na terceira etapa, os produtos obtidos foram purificados e quantificados por cromatografia gasosa, RMN 1H, viscosimetria e análise termogravimétrica (TGA). O conjunto de dados obtidos demonstrou que a formação de ésteres etílicos a partir das diferentes matérias-primas é viável para os catalisadores testados. Ambos os catalisadores (químico e bioquímico) atuaram de forma eficiente convertendo os ácidos graxos presentes nas matérias-primas lipídicas nos ésteres etílicos correspondentes e apresentaram elevada estabilidade em bateladas consecutivas, com destaque para o catalisador bioquímico que revelou um tempo de meiavida de 290 h. Entretanto, a qualidade da matéria-prima lipídica interferiu a atuação dos catalisadores de maneira diferenciada. Enquanto, o catalisador químico foi sensível a presença de níveis elevados de acidez, como o constatado no óleo de macaúba, a atuação do catalisador bioquímico sofreu influência da presença de peróxidos indicativo de oxidação apresentada pelo óleo de andiroba. Com exceção dos óleos de macaúba e andiroba que apresentaram qualidade comprometida, todas as matérias-primas lipídicas originaram amostras de biodiesel com características adequadas para serem usadas como combustível, incluindo valores de viscosidade entre 3,9 a 6,0 (cSt) que atendem as especificações estabelecidas na ASTM 6751- 02. Apesar do desempenho similar dos catalisadores testados, a via química foi superior em termos de produtividade em relação à via bioquímica. Entretanto, essa baixa produtividade pode ser incrementada utilizando métodos não convencionais de aquecimento, como por exemplo, irradiação de micro-ondas e ultrassom. Os resultados obtidos neste trabalho demonstram ainda que os catalisadores heterogêneos testados possuem potencial para substituir os sistemas homogêneos normalmente empregados na síntese do biodiesel. Essa substituição oferece vantagens, que podem propiciar um aumento considerável nas perspectivas de sustentabilidade sócio-ambiental de todo o processo de produção. / The present work aimed at studying the biodiesel synthesis by transesterification reaction from several lipidic feedstocks via ethyl route employing heterogeneous catalysts (chemical and biochemical). To attain the proposed objectives non-edible feedstock having low impact in the food segment, among which stand out: vegetable oils (andiroba, babassu, macauba, palm and Jatropha curcas) and residual fat (beef tallow) and potential catalysts as niobium oxide impregnated with sodium (chemical) and lipase from Burkholderia cepacia immobilized on silica-polyvinyl alcohol matrix (biochemical) were previously selected. The work was developed in three steps. Initially, the physico-chemical properties of the different lipidic feedstocks were investigated, some of them still little explored, to identify their potential as reactants in the transesterification reactions. Then the proposed catalysts were prepared by protocols already established, being obtained for the chemical catalyst high level of sodium impregnated in the niobium oxide (25.43 ± 0.29%) and for the biochemical catalyst high hydrolytic activity (1,814± 281 U/g). In the second step, the transesterification reactions were carried out in batch reactors under appropriated conditions for each catalyst in terms of temperature, time and catalyst proportion. In the third step, the obtained products were purified and quantified by gas chromatography, 1H NMR spectroscopy, viscosimetry and thermogravimetric analysis (TGA). The dataset obtained demonstrated that the formation of ethyl esters from the different feedstocks was feasible for the tested catalysts. Both catalysts (chemical and biochemical) were efficient in converting all fatty acids present in the lipidic feedstock into the corresponding ethyl esters and showed high stability under consecutive batch runs, with emphasis for the biochemical catalyst with a half-life time of 290 h. However, the poor quality of the feedstocks strong affected the performance of the catalysts in a different way. While the chemical catalyst was sensitive to high acidity levels, as verified in the macauba oil, the biochemical catalyst performance was influenced by the presence of peroxides indicating oxidation as showed in the andiroba oil. Except for these oils, all the other feedstocks originated biodiesel samples with appropriate characteristics to be used as fuel, including viscosity values between 3.9 to 6.0 (cSt) that are in accordance with specifications recommended by ASTM 6751-02. Even though the catalysts showed similar performances, the chemical route gave higher productivity than that attained by biochemical route. However, such lower productivity can be increased using non conventional heating systems as for instance, micro-wave irradiation and ultrasound. The results obtained in this work demonstrated that the selected heterogeneous catalysts possess potential to replace the homogeneous systems usually employed in the biodiesel synthesis. Such replacement offers advantages that can provided a considerable increase in the perspectives to attain an environmental sustainability of process as a whole.

Neste trabalho foi realizado o estudo de transformações de óleo de soja com o catalisador VO(acac)2 em meio homogêneo e heterogêneo. Estes processos catalíticos estão de acordo com os conceitos de química limpa, no sentido de economia de reagentes e diminuição de subprodutos, enquanto que a matéria-prima, óleo vegetal, foi escolhida por ser de fonte renovável, sustentável e abundante no Rio Grande do Sul e no Brasil. A reação de transesterificação do óleo de soja foi realizada através do sistema VO(acac)2 e VO(acac)2 suportado em uma argila celadonita, cujo depósito localiza-se na região de Ametista do Sul – RS. O sistema heterogêneo foi caracterizado pelas técnicas de DRX, BET, BJH, ATG, FTIR, CHN, MEV/EDS e ICP/OES. O teor de vanádio impregnado na argila foi de 1,06 %. O melhor rendimento das reações de transesterificação foi de 36 % e 30 % para os sistemas homogêneo e heterogêneo, respectivamente, para as condições de 2 % em mol e 5 % em mol de vanádio, a 65 ºC de temperatura e 48 horas de reação. Alguns testes foram realizados em reações de epoxidação. Do sistema celadonita/VO(acac)2 foi obtido conversão de 44 %, 15 % de monoepóxido e 34 % de seletividade, em 3 horas de reação. A avaliação quantitativa das reações foi realizada por RMN de 1H. / This work presents the study of soybean oil reactions with VO(acac)2 in homogeneous and heterogeneous catalytic systems. The catalytic systems follow the green chemistry principles of economy of reagents and reduction in sub-products of the reaction while the starting material, soybean oil, was chosen as a renewable source, sustainability of its crop and abundancy. Soybean oil transesterification reactions were done with the catalytic system VO(acac)2 and VO(acac)2 supported in celadonita, which is a mineral found in Ametista do Sul / RS. The heterogeneous system was characterized by the XRD, BET, BJH, TGA, FTIR, CHN, SEM/EDX and ICP/OES techniques. The amount of vanadium impregnated in the clay it was 1,06%. The best conditions for transesterification reaction gave 36 % yield for homogeneous system and 30 % yield for heterogeneous system, using 2 % molar and 5 % molar of vanadium, respectively, at 65 ºC of temperature and 48 hours of reaction. Some tests on epoxidation reactions were performed. With celadonita/VO(acac)2 system it was obtained a conversion of 44%, 15% of monoepoxide and 34 % of selectivity after 3 hours of reaction. The quantitative evaluation of the reactions was made by 1H NMR.

Actuellement, la stratégie de la production d’énergie repose sur les 3 concepts d’économie, de régénération et d’écologie. La production de biodiesel s’insère dans cette thématique et fait objet de ce travail. Un suivi cinétique de nucléation-croissance est réalisé sur des nanoparticules monodisperses d’oxo-alcoxydes de zirconium (ZOA). Ces nanoparticules sont préparées par voie sol-gel dans un réacteur à T-micro-mélangeur avec deux flux turbulents de ZNP et c dans 1-propanol à 20°C. Les nanodépôts des nanoparticules de ZOA ont été réalisés sur des substrats en silice et comparés aux nanopoudres récupérées après l’induction du sol de ZOA. Les nanodépôts et les poudres subissent un séchage à 80°C puis une imprégnation humide dans une solution aqueuse de 0,25 mol.L⁻¹ de H₂SO₄. Nous obtenons ainsi les nanodépôts catalytiques après une calcination à des températures comprises entre 500 et 700°C sous O₂. Les techniques de BET, ATG-ATD, MET, DRIFT, analyse élémentaire et DRX sont déployées pour caractériser ces catalyseurs. Les cinétiques du processus d’estérification et de transestérification ont été étudiées en fonction des conditions de la préparartion des catalyseurs nanostructurés. Les nanodépôts catalytiques acides de ZrO₂-SO₄²⁻ possèdent une activité catalytique 50 fois plus élevée que celle des nanopoudres dans la réaction d’estérification de l’acide palmitique dans le méthanol à 65°C. Les nanodépôts calcinés à 580°C ont la meilleure stabilité vis à vis des essais de recyclage. L’activité catalytique des nanodépôts est aussi valable avec d’autres charges dont la composition est similaire à celle des huiles non-comestibles puis celle des déchets gras. / In this work, we have realized novel nanoparticulate catalysts ZrO₂-SO₄²⁻ for biofuel production. We have studied nucleation-growth kinetics of zirconium-oxo-alkoxy (ZOA) nanoparticles in the sol-gel process. The monodispersed nanoparticles of 3.6 nm diameter were realised in a sol-gel reactor with rapid (turbulent) micro-mixing of liquid solutions containing ZNP and H₂O in 1-propanol at 20°C. The nanocoatings were realised of stable colloids of ZOA nanoparticles on silica beads along with common powders obtained after precipitation of unstable colloids. The acid ZrO₂-SO₄²⁻" catalysts were prepared after drying at 80°C, wet impregnation in 0.25 mol.L⁻¹ aqueous solution of sulfuric acid and subsequent thermal treatment between 500 and 700°C and studied with BET, DTA-DSC, TEM, DRIFT, elemental analysis, DRX and other methods. The catalyst nanocoatings calcinated at 580°C showed strong activity in esterification reaction of palmitic acid in methanol at 65°C, which is about 50 times higher than that of nanopowders, and also possesses the highest stability towards recycling. Tha catalytic performance of catalytic nanocoatings was also confirmed on unedible and waste oils.

The production of biofuels and oleochemicals from renewable sources offers an opportunity to reduce our dependence on fossil fuels. The work contained in this dissertation has focused on developing and improving methods for the production of biodiesel from non-traditional feedstocks and understanding biosynthetic pathways that result in the production of oleochemicals and fuels. Pure vegetable oil can account for 70-80% of the total cost of biodiesel production. Many low-cost oils contain high amounts of free fatty acids, which are unsuitable for base-catalyzed transesterification. Herein an approach is described that efficiently accomplishes the simultaneous esterification and transesterification of both free fatty acids and triglycerides found in low-cost oils. The approach utilizes an acid catalyst and longer-chain alcohols to improve biodiesel yields from oils high in free fatty acids. Microalgae are a promising biodiesel feedstock, due to its high lipid productivity and its ability to be cultivated using resources, land and water, unsuitable for agriculture. As part of this work, reaction conditions were optimized for the direct (or in situ) transesterification of algal biomass to biodiesel. This approach accomplishes the simultaneous extraction and conversion of the total lipids from microalgae and results in increased yields compared to extraction followed by conversion. The use of this process to effectively produce biodiesel from wet algal biomass is also discussed. Wax esters are a class of oleochemicals that can be used for a wide range of applications in diverse industries. The chemical composition of native wax esters from the bacterium Marinobacter aquaeolei was determined. It was found that including small alcohols in the growth medium resulted in the in vivo formation of esters similar to biodiesel. All of the proteins involved in the wax ester biosynthetic pathway are not known. The cloning, purification, and characterization of a putative fatty aldehyde reductase from M. aquaeolei, believed to be involved in the production of wax esters, is reported. Finally, the expression of a ws/dgat (wax ester synthase) gene from M. aquaeolei in the cyanobacterium Synechocystis sp. PCC 6803 is discussed as an approach to producing biodiesel in vivo from sunlight and CO2.

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.

<p>The production of biodiesel (methyl esters) from vegetable oils represents analternative means of producing liquid fuels from biomass, and one which is growing rapidly in commercial importance and relevance due to increase in petroleum prices and the environmental advantages the process offers. Commercially, biodiesel is produced from vegetable oils, as well as from waste cooking oils and animal fats. These oils are typically composed of C14-C20 fatty acid triglycerides. In order to produce a fuel that is suitable for use in diesel engines, these triglycerides are usually converted into the respective mono alkyl esters by base-catalyzed transesterification with short chain alcohol, usually methanol. In the first part of this study, the transesterification reactions of three different vegetable oils / sunflower (SFO), soybean (SBO) and waste cooking oil (WCO) with methanol was studied using potassium hydroxide as catalyst in a conventional batch process. The production of biodiesel from waste cooking oil was also studied via continuous operation systems (employing the use of low frequency ultrasonic technology and the jet loop reactor). The characterisation of the feedstock used and the methyl ester products were determined by different analytical techniques such as gas chromatography (GC), high performance liquid chromatography (HPLC) and thin layer chromatography (TLC). The effects of different reaction parameters (catalyst amount, methanol to oil ratio, reaction temperature, reaction time) on methyl ester/FAME yield were studied and the optimum reaction conditions of the different process systems were determined. The optimum reaction conditions for production of methyl esters via the batch process with the fresh oil samples (SFO and SBO) were established as follows: a reaction time of 60 min at 60 &ordm / C with a methanol: oil ratio of 6:1 and 1.0 KOH % wt/wt of oil / while the optimum reaction conditions for the used oil (WCO) was observed at a reaction time of 90 min at 60 &ordm / C, methanol: oil ratio of 6:1 and 1.5% KOH wt/wt of oil. The optimum reaction conditions for the transesterification of the WCO via ultrasound technology applied in a continuous system in this study were: a reaction time of 30 min, 30 &ordm / C, 6:1 methanol/oil ratio and a 0.75 wt% (KOH) catalyst concentration. The ultrasound assisted transesterification reactions performed at optimum conditions on the different oil samples led to higher yields of methyl esters (96.8, 98.32 and 97.65 % for WCO, SFO and SBO respectively) compared to methyl esters yields (90, 95 and 96 % for WCO, SFO and SBO respectively) obtained when using conventional batch procedures. A considerable increase in yields of the methyl esters in the ultrasound assisted reaction process were obtained at room temperature, in a remarkably short time span (completed in 30 min) and with a lower amount of catalyst (0.75 wt % KOH) while the results from the continuous jet loop process system showed even better results, at an optimum reaction condition of 25 min of reaction, a methanol: oil ratio of 4:1 and a catalyst amount of 0.5 wt%. This new jet loop process allowed an added advantage of intense agitation for an efficient separation and adequate purification of the methyl esters phase at a reduced time of 30 min. The use of homogeneous catalysts in conventional processes poses many disadvantages / heterogeneous catalysts on the other hand are attractive on the basis that their use could enable the biodiesel production to be more readily performed as a continuous process resulting in low production costs. Consequently, a solid base catalyst (KNO3/FA) prepared from fly ash (obtained from Arnot coal power station, South Africa) and a new zeolite, FA/Na-X synthesized from the same fly ash were used as solid base catalysts in the transesterification reactions in the conversion of a variety of oil feedstock with methanol to methyl esters. Since fly ash is a waste product generated from the combustion of coal for power generation, its utilization in this manner would allow for its beneficiation (as a catalytic support material and raw material for zeolite synthesis) in an environmentally friendly way aimed at making the transesterification process reasonably viable. Arnot fly ash (AFA) was loaded with potassium (using potassium nitrate as precursor) via a wet impregnation method while the synthesized zeolite FA/Na-X was ion exchanged with potassium (using potassium acetate as precursor) to obtain the KNO3/FA and FA/K-X catalysts respectively. Several analytical techniques were applied for characterization purposes. The results of the XRD and XRF showed that the AFA predominantly contained some mineral phases such as quartz, mullite, calcite and lime. The high concentration of CaO in AFA was apparent to be beneficial for the use of fresh fly ash as a support material in the heterogeneous catalysed transesterification reactions. XRD characterisation of KNO3/FA results indicated that the structure of KNO3/FA gradually changed with the increase in KNO3 loading. The catalyst function was retained until the loading of KNO3 was over 10 %. IR spectra showed that the KNO3 was decomposed to K2O on the fly ash support during preparation at a calcination temperature of 500 &ordm / C. The CO2-TPD of the KNO3/FA catalysts showed that two basic catalytic sites were generated which were responsible for high catalytic abilities observed in the transesterification reactions of sunflower oil to methyl esters. On the other hand, XRD results for the as- received zeolite synthesized from AFA showed typical diffraction peaks of zeolite NaX. SEM images of the FA /NaX showed nano platelets unique morphology different from well known pyramidal octahedral shaped crystal formation of faujasite zeolites and the morphology of the FA /KX zeolite did not show any significant difference after ion exchange. The fly ash derived zeolite NaX (FA /NaX) exhibited a high surface area of 320 m2/g. The application of the KNO3/FA catalysts in the conversion reactions to produce methyl esters (biodiesel) via transesterification reactions revealed methyl ester yield of 87.5 % with 10 wt% KNO3 at optimum reaction conditions of methanol: oil ratio of 15:1, 5 h reaction time, catalyst amount of 15 g and reaction temperature 160 &deg / C, while with the use of the zeolite FA/K-X catalyst, a FAME yield of 83.53 % was obtained for 8 h using the ion exchanged Arnot fly ash zeolite NaX catalyst (FA/KX) at reaction conditions of methanol: oil ratio of 6:1, catalyst amount of 3 % wt/wt of oil and reaction temperature of 65 &ordm / C. Several studies have been carried out on the production of biodiesel using different heterogeneous catalysts but this study has been able to uniquely demonstrate the utilization of South African Class F AFA both as a catalyst support and as a raw material for zeolite synthesis / these catalyst materials subsequently applied sucessfully as solid base catalysts in the production of biodiesel.</p>

Ion exchange resins, commonly used in water treatment, demonstrate promise for the production of biodiesel from biomass feedstocks. The goal of this presented PhD research is to investigate novel uses of ion exchange resins for processing biodiesel feedstocks. Specifically, this research explored using ion exchange resins to remove free fatty acids (FFA) from soybean and waste cooking oils, catalyze transesterification of soybean oil, and catalyze in-situ conversion of dried algal biomass to biodiesel and other recoverable organics. The effect of temperature, moisture content, mixing rate, and resin drying on deacidification of soybean oil with 5% oleic acid feedstock was explored using Dowex Monosphere MR-450 UPW within a batch reactor. The resins were observed to remove up to 83 +/- 1.3% of FFA from soybean oil with less than 5% moisture content while operated at a 20% resin loading at 50 degrees C while mixing at 550 rpm. Once operation characteristics impacting deacidification were evaluated, a series of experiments were carried out to demonstrate the use of mixed bed resin to remove FFA from waste cooking oils. An investigation of wash solutions capable of regenerating the resins was also carried out. Using methanol to regenerate the resins resulted in more than 40% FFA removal over three regeneration cycles, highlighting the utility of resin regeneration as a cost saving measure. Transesterification of soybean oil on Amberlyst A26-OH, a basic ion exchange resin, in the presence of excess methanol was carried out to determine the mechanism of the reaction occurring on the surface. A batch reactor approach was used and reactions were carried out with and without FFA present in the soybean oil feed stock at a 20% resin loading at 50 degrees C while mixing at 550 rpm. When FFA was present in the feedstock and methanol is present in excess, the rate constant for methanol consumption increased. Based upon model fitting, the rate constant of methanol consumption was determined to be 2.08 x 10^-7 /sec with FFA absent and 5.39 x 10^-4/sec when FFA is present when the Eley-Rideal model was used to fit the data. In-situ conversion of dried algal biomass to biodiesel and other recoverable organics was investigated using a batch reaction system with 1 gram of algae. The system was operated with 40:60 methanol:hexane as the solvent system operated at 50 degrees C while mixing at 550 rpm over a range of catalyst loadings. The highest observed ester yield, approximately 60% yield (37 mg_ester/g_algae), was observed when air dried algae was reacted with a 20% resin. An evaluation of the reaction products showed a mixture of esters, phytol, alcohols, and ketones; highlighting the complexity of the reactions occurring during in-situ biomass conversion.

La dawsonita es un mineral cristalino hallado generalmente en la naturaleza en forma de hidróxicarbonato de sodio y aluminio, NaAlCO3(OH)2. Además del mineral, se han sintetizado diferentes tipos de dawsonitas variando su composición, es decir, cambiando el sodio y/o aluminio por cationes de similar naturaleza. El trabajo descrito en esta tesis se centra en estudiar la química de este tipo de compuestos incluyendo: la estabilidad en medios acuosos de las dawsonitas en condiciones moderadas, la obtención de compuestos nanoestructurados dawsonita-hidrotalcita a partir de hidrotalcita, y el efecto memoria de las alúminas derivadas de dawsonita. El objetivo final es la evaluación de los materiales sintetizados y sus derivados, en catálisis. Estos materiales han resultado ser eficientes o en algunos casos más activos que los catalizadores reportados en la literatura para reacciones básicas (la transesterificación de carbonato de etileno para producir carbonato de dimetilo) y redox (epoxidación de alquenos). Teniendo en cuenta los resultados obtenidos, estos materiales podrían ser utilizados como catalizadores, adsorbentes, y aditivos abriendo así una nueva vía de investigación. / Dawsonites are crystalline minerals generally present in nature as sodium aluminum carbonate hydroxide, NaAlCO3(OH)2. Besides the mineral, a variety of compositions with dawsonite-type structure have been synthesized by changing the nature of sodium or aluminum cations. The work described in this thesis focuses on the chemistry of dawsonite-type compounds including: the stability of dawsonites in aqueous media at mild conditions; the achievement of dawsonite-hydrotalcite nanostructured composites starting from the hydrotalcite; and the memory property of dawsonite-derived aluminas. The final goal is to evaluate the as-synthesized or derived dawsonite-materials in selected catalytic reactions. These materials were efficient or even more active than catalysts in the state-of-the-art in basic (dimethyl carbonate production by transesterification of ethylene carbonate with methanol) and redox (alkene epoxidation of cyclooctene with hydrogen peroxide) reactions. The above findings could have further practical implications as activated dawsonites open a new window of research with potential applications as catalysts, adsorbents, and additives.

This study used jatropha oil, waste cooing oil, and soybean oil as the raw materials for investigating effects of catalyst concentration, reaction time, reaction temperature, methanol-to-oil ratio, and catalyst types on biodiesel yield. The authors also heated up the oil to speed up the transesterification and to make the reaction more complete. Jatropha oil, waste cooing oil, and soybean oil were used as the raw materials, and three types of ionic liquid or zwitterionic liquid, [PyrMe][HSO4], [PyrMeBuS][HSO4], and [MorMeA][Br], were added as catalysts for co-catalysis while heating the oil raw materials to create the best operational condition for biodiesel production. For soybean oil used as the raw material, the best catalyzing effect (a 99.4% yield) was achieved by adding [MorMeA][Br] while the reaction time was 6min, reaction temperature was 70 ¢J, and the methanol-to-oil ratio was 9:1. Under the best reaction condition, catalyzing effect was compared between the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid. The yield of the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid were 97.2% and 98.7% respectively. It can be found from this study that for increasing biodiesel yield, the addition of zwitterionic liquid for co-catalysis is more effective than the addition of homogeneous ionic liquid. Comparing the best operational condition between jatropha oil and soybean oil, the best yield of jatropha oil and soybean oil was 98.5% and 99.4% respectively, while the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 6 min, and the reaction temperature was 70¢J. As for disposed cooking oil, the best operational condition rendered a yield of 98.1% when the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 7 min, and the reaction temperature was 70¢J. For waste cooking oil, because of the containing of impurities from frying, the yield was slightly lower and the reaction time was longer.

<p>This work describes how a fatty acid methyl ester (FAME) derived from a vegetable oil can be introduced as reactive diluent in a solvent-borne thermally cured coil-coating system. The evaluated reactive diluent, rape seed methyl ester (RME), has been evaluated both in a fully formulated clear coat system and via model studies.</p><p>A reactive diluent is a compound that acts as a solvent in the liquid paint, lowering the viscosity, and chemically reacts into the final film during cure. Introduction of a reactive diluent derived from vegetable oil give a more environmental compliant coating since a renewable material is incorporated in the coating and the amount of traditional solvent can be decreased. These positive environmental factors have increased the industrial interest.</p><p>The fully formulated clear coat studies describes how addition of reactive diluent affects rheological properties of the wet paint, film formation, incorporation, and final film properties in a hydroxyl-functional polyester/melamine coil-coating system. The coating were cured under industrial coil-coating cure conditions and analyzed with Raman, carbon-14 dating, extraction, dynamic mechanical analysis, and visually observed. Viscosity measurement of the wet paint show that RME works as a diluent. RME increase the mobility in the system enhancing the film formation process and occurrence of defect-free films. The incorporation of RME could not be confirmed by Raman analysis. However, carbon-14 dating did indicate the presence of RME that could not be extracted from the films. The appearance and mechanical properties of the films were also significantly affected by addition of RME. Dynamic mechanical analysis of the free standing films showed that the final film properties were affected by oven temperature, choice of co-solvent, and flash-off period.</p><p>Model studies were performed to further clarify how RME chemically can react through transesterification with the hydroxyl-groups of the polyester. RME and its two main components methyl oleate and methyl linoleate were reacted with primary alcohols with and without tertiary hydrogen both under low temperature (110, 130, 150, 170°C) and industrial cure conditions. The transesterification reaction was monitored with 1H-NMR and real time IR. Evaporation and side reactions, e.g. oxidation, are competing factors with the transesterification reaction. The fatty acid structure affects the conversion as a higher amount of unsaturations triggers higher degree of oxidation. The study also showed that reaction time and temperature affects the transesterification conversion, degree of side reactions, and catalyst choice.</p>