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1
Pisac, Claudia A. "An experimental study of combustion characteristics of fatty acid methyl ester biodiesel." Thesis, University of Hertfordshire, 2014. http://hdl.handle.net/2299/14641.
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The thesis presents an experimental investigation of combustion performance and emissions of waste cooking oil (WCO) based biodiesel. To evaluate the comparative performance of biodiesel and diesel, combustions tests were conducted using Continuous Combustion rig (CCR) and Land Rover VM diesel engine. Firstly, physical properties of WCO biodiesel and diesel samples were measured in the laboratory. Elemental analysis of WCO biodiesel showed that there are differences between the functional groups in diesel and biodiesel which lead to major differences in the combustion characteristics of the two fuel types. It was found that biodiesel had 10% lower carbon content, almost no sulphur content for biodiesel and up to 12% more oxygen content compared with diesel. This explains the lower caloric value for WCO biodiesel (up to l8 %) compared with diesel. However, higher oxygen content and double bounds in WCO biodiesel increase its susceptibility to oxidation. The CCR test results showed an increase in combustion gas temperature with the increases in biodiesel blend ratio in diesel. This was due to a faster reaction rate for biodiesel than that of diesel leading to a faster brakeage of the hydrocarbon chain to release more heat. The engine tests were performed to measure the torque and emissions for different engine speeds and loads. In general a decrease in engine torque with up to 9% for biodiesel was observed, which was due to the lower calorific value of biodiesel compared with that of diesel. The brake specific fuel consumption (BSFC) increased as the biodiesel blend ratio in diesel increases due a greater mass of fuel being injected at a given injection pressure, compared with diesel. Using WCO blends ratio up to 75% in diesel showed a reduction in exhaust emission compared with diesel, however, at the cost of increased fuel consumption. A common conclusion can be drawn in favour of the WCO biodiesel as being a greener alternative to petro-diesel when used in blend with diesel. However, due to large variations in the biomass used for biodiesel production could lead to variations in physical and chemical properties between biodiesel produced from different biomass. Therefore more stringent standards need to be imposed for biodiesel quality in order to diminish the effect of variation in physicochemical properties on engine performance and emissions. The future work in developing standard test procedures for establishing fuel properties and limits/targets would be beneficial in using a large amount of waste cooking oil in the production of biodiesel, thus contributing to reduction in CO2 and waste minimisation.
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Bentley, David James. "Cyclic peptides : total synthesis of stephanotic acid methyl ester and approaches toward moroidin." Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425241.
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De, Castro Ana Maria. "Fatty acid methyl ester analysis of microbial communities in biofilters inoculated with different sources." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28820.pdf.
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Zhao, Peng. "The Attempted Synthesis of Carba-Nicotinic Acid Mononucleotide Methyl Ester using the Zincke Reaction." University of Toledo Health Science Campus / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=mco1488576282701401.
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Bollin, Patrick M. "The Production of Fatty Acid Methyl Esters in Lewis Acidic Ionic Liquids." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321507054.
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Kadisch, Marvin [Verfasser]. "Stabilizing whole-cell biocatalysts : En route to more efficient fatty acid methyl ester bioprocessing / Marvin Kadisch." Aachen : Shaker, 2017. http://d-nb.info/1149269103/34.
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Banerjee, Sagarika. "EFFECTS OF LIVESTOCK ANTIBIOTICS ON NITRIFICATION, DENITRIFICATION, AND MICROBIAL COMMUNITY COMPOSITON IN SOILS ALONG A TOPOGRAPHIC GRADIENT." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/43.
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Several types of antibiotics (roxarsone, virginiamycin, and bacitracin) are widely included in poultry feed to improve animal growth yields. Most of the antibiotics are excreted in manure which is subsequently applied to soils. One concern with this practice is that antibiotics may affect several microbially-mediated nutrient cycling reactions in soils that influence crop productivity and water quality. The main objectives of this study were to determine the effects of livestock antibiotics on nitrification, denitrification, and microbial community composition in soils along a topographic gradient. These objectives were addressed in a series of lab experiments by monitoring changes in inorganic N species and ester-linked fatty acid methyl ester profiles after exposing soil microorganisms collected from different topographic positions to increasing levels of antibiotics. It was discovered that roxarsone and virginiamycin inhibited nitrification and soil microbial growth and also influenced microbial community composition, but only at levels that were much higher than expected in poultry litter-applied soils. Bacitracin did not affect nitrification, microbial growth, or microbial community composition at any concentration tested. None of the antibiotics had a strong affect on denitrification. Thus, it is unlikely that soil, water, or air quality would be significantly impacted by the antibiotics contained in poultry litter.
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Huq, Abul Fatha Md Anisul. "Interfacial and Solvent Processing Control of Phenyl-C61-Butyric Acid Methyl Ester (PCBM) Incorporated Polymer Thin Films." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427746818.
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Kerman, Ipek. "Synthesis And Characterization Of Poly(oxalic Acid Dithiophen-3-yl Methyl Ester) And Thiophene Ended Poly-&." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605014/index.pdf.
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Synthesis and characterization of thiophene ended poly-&<br>#949<br>-caprolactone (PCL) and oxalic acid dithiophen-3-yl methyl ester (ODME) and their copolymers with both pyrrole and thiophene were achieved. Chemical structure of the precursor polymer and monomer were investigated Redox behavior of polymer and monomers were determined by Cyclic Voltammetry (CV). Structural characterization of samples were carried out by 1H, 13C Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Conductivities of the films were measured by using four probe technique. Thermal analyses of conducting copolymers were investigated via Differential Scanning Calorimetry (DSC) and Thermal Gravimetry Analysis (TGA). The morphologies of the copolymer films were examined by Scanning Electron Microscopy (SEM). Electrochromic and spectroelectrochemical behavior of the copolymers were investigated, and their ability of employment in device construction has been examined.
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Bahceci, Humeyra. "Fatty Acid Methyl Ester Analysis Of Bacterial Isolates From Salt Lake, Turkey And Characterization Of Their Extracellular Enzymes." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605483/index.pdf.
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In this study, 11 bacterial isolates from Salt Lake,Turkey were identified by using fatty acid methyl ester (FAME) analysis. They were screened for production of industrially important enzymes xylanase, cellulase, &<br>#945<br>-amylase and protease. These enzymes were characterized in terms of enzyme activity, stability, optimum temperature and optimum pH.
One of the isolates was identified as Bacillus pumilus, and two of them were identified as Bacillus subtilis. Other isolates were determined to be Bacillus licheniformis.
All the isolates were determined to produce xylanase. Optimum temperatures and optimum pH values of xylanases were 50-55 °<br>C and pH 7.0-8.0. Xylanases were quite stable up to pH 8.0 and 70 °<br>C. Isolates were not significant cellulase
producers. Four of the isolates did not produce any cellulase enzyme and the rest produced negligible amounts of cellulase. Therefore, xylanases from the isolates were promising for pulp and paper industry, which requires cellulase free and stable xylanases.
All the isolates produced appreciable quantities of &<br>#945<br>-amylase. Optimum temperatures and optimum pH values of &<br>#945<br>-amylases 60-80 °<br>C and pH 7.0-8.0. &<br>#945<br>-Amylases were quite stable up to pH 9.0 and 80 °<br>C. &<br>#945<br>-Amylases from the isolates were promising for starch processing industry, which requires &<br>#945<br>-amylases stable at high temperatures and for detergent industry, which requires &<br>#945<br>-amylases stable at alkaline pH values.
Considerable protease productions were achieved by all the isolates. TTG 2 was the best protease producer with 271 U/ml. Optimum temperatures and optimum pH values of proteases were 50-60 °<br>C and pH 7.0-7.4. Proteases were quite stable up to pH 9.0 and 80 °<br>C. Proteases from the isolates were promising for detergent and leather industry, in which proteases must be stable at alkaline pH values.
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Westberg, Emilie. "Qualitative and Quantitative Analysis of Biodiesel Deposits Formed on a Hot Metal Surface." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-95617.
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This thesis aims to investigate the formation of deposits from thermally degraded biodiesel on a hot metal surface under the influence of sodium or copper contaminations. Biodiesel or Fatty Acid Methyl Esters (FAMEs) is a widely utilized biofuel with the potential to replace fossil fuels, however, issues regarding the thermal and oxidative stability prevent the progress of biodiesel for utilization as vehicle fuel. The thermal degradation of biodiesel causes formation of deposits often occurring in the fuel injectors, which could result in reduced engine efficiency, increased emissions and engine wear. However, still have no standard method for evaluation of a fuels’ tendency to form deposits been developed. In this study biodiesel deposits have been formed on aluminum test tubes utilizing a Hot Liquid Process Simulator (HLPS), an instrument based on the principle of the Jet Fuel Thermal Oxidation Tester (JFTOT). Quantitative and qualitative analyses have been made utilizing an array of techniques including Scanning Electron Microscopy (SEM), Gas Chromatography Mass Spectrometry (GCMS) and Attenuated Total Reflectance Fourier Transform Infrared Spectrometry (ATR-FTIR). A multi-factorial trial investigating the effects of sodium hydroxide and copper contaminations at trace levels and the impact of a paraffin inhibitor copolymer additive on three different FAME products, two derived from rapeseed oil and one from waste cooking oil as well as a biodiesel blend with mineral diesel, was conducted.The results exhibited that FAMEs are the major precursor to deposit formation in diesel fuel. The SEM analyses exploited the nature of FAME deposits forming porous structures on hot metal surfaces. Sodium hydroxide proved to participate in the deposit formation by forming carboxylic salts. However, the copper contamination exhibited no enhancing effect on the deposits, possibly due to interference of the blank oil in which copper was received. The paraffin inhibitor functioning as a crystal modifier had significant reducing effect on the deposit formation for all biodiesel samples except for the FAME product derived from waste cooking oil. Further studies are needed in order to investigate the influence of glycerin and water residues to the biodiesel deposit formation. Mechanisms involving oxidative or thermal peroxide formation, polymerization and disintegration have been suggested as degradation pathways for biodiesel. The involvement of oxidation intermediates, peroxides, was confirmed by the experiments performed in this thesis. However, the mechanisms of biodiesel deposit formation are complex and hard to study as the deposits are seemingly insoluble. Nevertheless, ATR-FTIR in combination with JFTOT-processing has potential as standard method for evaluation of deposit forming tendencies of biodiesel.
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Tappertzhofen, Nadine [Verfasser]. "Multistep biocatalysis for the sequential oxy- and amino-functionalization of renewable dodecanoic acid methyl ester : Strain engineering and process design / Nadine Ladkau." Aachen : Shaker, 2015. http://d-nb.info/1069044415/34.
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van, Pelt Thomas. "Thin films of [6,6]-phenyl-C61-butyric acid methyl ester for application in organic solar cells : preparation and effects of exposure to light and heat." Thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-27500.
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Maios, Claudia. "Expression of defence-related genes in sugar beet plants infected with Rhizoctonia solani and treated with benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH)." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99349.
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The chemicals inducers SA, BABA, and BTH were tested as seed treatment and soil drench on a partial-resistant cultivar of sugar beet grown in sand infested with the Rhizoctonia solani AG 2-2IIIB. In another series of experiments, BTH was applied as soil drench on sugar beet plants inoculated with R. solani. The chemical inducers were ineffective in reducing pre-emergence damping-off and post-emergence plant mortality. Despite these results, treatment with BTH altered the levels of expression ratios of four defence encoding genes associated with systemic resistance: chitinase, peroxidase, chalcone isomerase, and chalcone synthase. BTH sensitised sugar beet plants without the necessity of R. solani infection to up-regulate substantially the transcript level ratios of chalcS and chit3, while levels of chalcI were down-regulated levels below 1. Of interest, was the significant increase of transcript levels of chit3 in sugar beet plants infected with R. solani and treated with BTH. In conclusion, sugar beet plants were capable of over expressing selected genes in response to a chemical inducer, but contrary to what had been reported, gene activation in sugar beet as a result of BTH treatment does not confer disease resistance against R. solani.
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EMILIO, CLAUDIA R. "Comparacao da eficacia do acido 5-aminolevulinico com a de seu metil ester utilizando-se a terapia fotodinamica no tratamento de carcinoma espinocelular felino." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11730.
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Made available in DSpace on 2014-10-09T12:55:12Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:05:58Z (GMT). No. of bitstreams: 0<br>Tese (Doutoramento)<br>IPEN/T<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Testud, Blandine. "Les huiles végétales comme plateforme pour la conception de nouveaux polyesters hyper-ramifiés." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0365/document.
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Ces travaux de thèse traitent de la valorisation des huiles végétales comme plateforme pour la synthèse de polyesters d’architecture hyper-ramifiée. Pour ce faire, l’approche par polycondensation de monomères de type ABn (n ≥ 2) a été privilégiée. Des précurseurs plurifonctionnels portant des fonctions ester (A) et alcool (B) ont ainsi été préparés par modification chimique d’huiles végétales et/ou d’esters méthyliques d’acide gras. Plusieurs méthodologies de synthèse simple, sûres et efficaces ont été mises en place afin de garantir une réalité industrielle à ce projet. Deux plateformes de monomères de type ABn ont été obtenues par (1) hydrolyse acide d’huiles végétales époxydées et (2) en faisant appel à des réactions d’addition de thiol-ène et de métathèse. Le développement de procédés de polycondensation en masse, a alors permis l’accès à de nouveaux polyesters hyper-ramifiés. La densité de ramifications ainsi que les propriétés thermo-mécaniques de ces matériaux ont été modulées par le choix adapté de la structure chimique des précurseurs ‘gras’ utilisés. Enfin, un travail exploratoire a été conduit concernant la post-fonctionnalisation du coeur comme de la périphérie de ces polyesters hyper-ramifiés dans le but de moduler leurs propriétés et ainsi d’étendre la portée de leurs applications, des plastiques de commodité aux matériaux avancés<br>The aim of this thesis was to use vegetable oils as a platform for the design of more sustainable polyesters of hyperbranched architecture. For that purpose, the approach by polycondensation of ABn-type monomers (n ≥ 2) was favored. Plant oils and/or fatty acid methyl esters were chemically modified to synthesize multifunctional precursors featuring ester (A) and alcohol moieties (B). Simple, safe and efficient chemical transformations were considered to provide industrial perspectives to this work. Two main platforms of ABn-type monomers were developed by (1) acid hydrolysis of epoxidized vegetables oils and (2) thiol-ene/metathesis coupling reactions. The subsequent polycondensation of these oily-derived monomers, performed in bulk, gave access to novel renewable hyperbranched polyesters. The branching density as well as the thermo-mechanical properties of these materials were adjusted by designing and selecting the chemical structure of the fatty acid-based monomers. Finally, an exploratory work was carried out regarding the post-functionalization of both the core and the periphery of these hyperbranched polyesters with the aim at tuning their properties and thus opening the scope of their applications, from commodity plastics to advanced materials
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Lancaster, Sarah Renee. "Soil microbial response to glyphosate-base cotton pest management systems." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2636.
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Saleh, Jehad. "A Membrane Separation Process for Biodiesel Purification." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19730.
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In the production of biodiesel via the transesterification of vegetable oils, purification to international standards is challenging. A key measure of biodiesel quality is the level of free glycerol in the biodiesel. In order to remove glycerol from fatty acid methyl ester (FAME or biodiesel), a membrane separation setup was tested. The main objective of this thesis was to develop a membrane process for the separation of free glycerol dispersed in FAME after completion of the transesterification reaction and to investigate the effect of different factors on glycerol removal. These factors included membrane pore size, pressure, temperature, and methanol, soap and water content.
First, a study of the effect of different materials present in the transesterification reaction, such as water, soap, and methanol, on the final free glycerol separation was performed using a modified polyacrylonitrile (PAN) membrane, with 100 kD (ultrafiltration) molecular weight cut off for all runs at 25°C. Results showed low concentrations of water had a considerable effect in removing glycerol from the FAME. The mechanism of separation of free glycerol from FAME was due to the removal of an ultrafine dispersed glycerol-rich phase present in the untreated (or raw) FAME. The size of the droplets and the free glycerol separation both increased with increasing water content of the FAME.
Next, three types of polymeric membranes in the ultrafiltration range with different molecular weight cut off, were tested at three fixed operating pressures and three operating temperatures (0, 5 and 25oC) to remove the free glycerol from a biodiesel reactor effluent. The ASTM standard for free glycerol concentration was met for the experiments performed at 25°C. The results of this study indicate that glycerol could be separated from raw FAME to meet ASTM and EN standards at methanol feed concentrations of up to 3 mass%. The process was demonstrated to rely on the formation of a dynamic polar layer on the membrane surface.
Ceramic membranes of different pore sizes (0.05 µm (ultrafiltration (UF) range) and 0.2 µm (microfiltration (MF) range)) were used to treat raw FAME directly using the membrane separation set up at temperatures of 0, 5 and 25°C. The results were encouraging for the 0.05 µm pore size membrane at the highest temperature (25°C). The effect of temperature on glycerol removal was evident from its relation with the concentration factor (CF). Higher temperatures promoted the achievement of the appropriate CF value sooner for faster separation. Membrane pore size was also found to affect separation performance.
A subsequent study revealed the effect of different variables on the size of the glycerol droplets using dynamic light scattering (DLS). A key parameter in the use of membrane separation technology is the size of the glycerol droplets and the influence of other components such as water, methanol and soaps on that droplet size. The effect of water, methanol, soap and glycerol on the size of suspended glycerol droplets in FAME was studied using a 3-level Box-Behnken experimental design technique. Standard statistical analysis techniques revealed the significant effect of water and glycerol on increasing droplet size while methanol and soap served to reduce the droplet size.
Finally, a study on the effect of trans-membrane pressure (TMP) at different water concentrations in the FAME phase on glycerol removal using UF (0.03 µm pore size, polyethersulfone (PES)) and MF (0.1 and 0.22 µm pore sizes, PES) membranes at 25, 40 and 60°C was performed. Results showed that running at 25°C for the two membrane types produced the best results for glycerol removal and exceeded the ASTM and EN standards. An enhancement of glycerol removal was found by adding small amounts of water up to the maximum solubility limit in biodiesel. An increase in temperature resulted in an increase in the solubility of water in the FAME and less effective glycerol removal. Application of cake filtration theory and a gel layer model showed that the gel layer on the membrane surface is not compressible and the specific cake resistance and gel layer concentration decrease with increasing temperature. An approximate value for the limiting (steady-state) flux was reported and it was found that the highest fluxes were obtained at the lowest initial water concentrations at fixed temperatures.
In conclusion, dispersed glycerol can be successfully removed from raw FAME (untreated FAME) using a membrane separation system to meet the ASTM biodiesel fuel standards. The addition of water close to the solubility limit to the FAME mixture enables the formation of larger glycerol droplets and makes the separation of these droplets straightforward.
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Nguyen, van Cuong. "Maîtrise de l'aptitude technologique des oléagineux par modification structurelle : applications aux opérations d'extraction et de transestérification in-situ." Thesis, La Rochelle, 2010. http://www.theses.fr/2010LAROS308/document.
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Le présent travail de thèse porte sur l’étude de l’impact de la texturation par DIC (Détente Instantanée Contrôlée) sur les deux opérations d’extraction d’huile et de transestérification in-situ appliquées aux graines de colza et fèves de Jatropha Curcas. Une analyse fondamentale a prouvé l’importance de la diffusion du solvant ou réactif dans la matrice solide, et permis d’identifier les processus d’intensification au travers des trois caractéristiques physiques de diffusivité effective, d’accessibilité initiale et de rendement d’extraction ; ainsi que la cinétique de transestérification in-situ et le rendement d’ester méthylique d’acides gras. Une étude phénoménologique a permis de déterminer les diverses valeurs de ces caractéristiques en fonction des paramètres opératoires DIC (pression de vapeur d’eau saturée P et temps de traitement t).Dans le cas d’extraction, la diffusivité effective (Deff) de produits traités par DIC peut atteindre 8,01 10-12 m2/s contre 0,715 10-12 m2/s pour le colza non traité et 5,90 10-12 m2/s contre 2,42 10-12 m2/s pour le jatropha non traité. Le taux d’accessibilité initiale de produits traités par DIC peut atteindre 80,53% contre 26,71% pour le colza non traité et 92,58% contre 75,91% pour le jatropha non traité. Au plan du rendement, la DIC a pu impliquer un rendement de 153% pour le colza et 112% pour le jatropha.Dans le cas de la transestérification in-situ, les rendements d’esters méthyliques d’acides gras totaux (FAME total) obtenus pour les produits traités par DIC sont systématiquement supérieurs à ceux de la matière première non traitée par DIC pour les deux cas de colza et de jatropha. Le temps de réaction a été réduit à 30 - 45 minutes contre 120 minutes pour le produit non traité par DIC (cas de colza) et à 15 minutes au lieu de 60 minutes pour le produit non traité par DIC (cas de fèves de jatropha)<br>The present work has concerned the impact of Instant - Controlled Pressure Drop (DIC) texturing on both operations of oil extraction and in-situ transesterification, carried out with the rapeseed and the kernels of Jatropha Curcas. A fundamental analysis proved the importance of the reactive or solvent diffusion within the solid matrix. By texturing the natural product, the whole operation can be intensified. The process is revealed through three characteristics, which are the effective diffusivity, the starting accessibility, and the yields of extraction. Also, the kinetics and yield of fatty acid methyl ester of in-situ transesterification are discovered. A phenomenological study allowed determining the value of these characteristics versus DIC operating parameters (saturated steam pressure P and treatment time t).A 2 h solvent extraction of DIC treated material allowed the total oil yields to be improved by 153% for colza and 112% for jatropha, the effective diffusivity (Deff) can reach up to 8.014*10-12 m2/s as against 0.715*10-12 m2/s for colza untreated by DIC, and up to 5.90*10-12 m2/s as against 2.42*10-12 m2/s for the untreated jatropha. The rate of initial accessibility of products treated by DIC can reach up to 80.53% as against 26.71% for untreated colza and can reach up to 92.58% as against 75.91% for the product untreated jatropha. In the case of in situ transesterification, the total yield of fatty acid methyl esters (FAME total) obtained from the DIC treated products is systematically higher than that of untreated colza and jatropha raw material. The reaction time was decreased to 30 - 45 min instead of 120 min in the case of colza, and to 15 min instead of 60 min in the case of jatropha kernel
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Pourkhesalian, Ali Mohammad. "Effects of biodiesel chemical composition on the chemical and physical properties of the primary and secondary diesel particulate matter." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/86757/14/86757_Ali_Mohammad_Pourkhesalian_Thesis.pdf.
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This thesis improves our insight towards the effects of using biodiesels on the particulate matter emission of diesel engines and contributes to our understanding of their potential adverse health effects. The novelty of this project is the use of biodiesel fuel with controlled chemical composition that enables us to relate changes of physiochemical properties of particles to specific properties of the biodiesel. For the first time, the possibility of a correlation of the volatility and the Reactive Oxygen Species concentration of the particles is investigated versus the saturation, oxygen content and carbon chain length of the fuel.
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Dastjerdi, Zahra. "The Esterification of Naphthenic Acids for Methyl Ester Production." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28802.
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The remediation of tailings water, a by-product of bitumen extraction, is of utmost importance to the Athabasca oil sands industry due to its toxicity to aquatic environments. Naphthenic acids (NAs), natural components of bitumen, are the major contributor to the toxicity of tailings water. The use of algae for remediation of tailings water is a new approach to reduce the toxicity of tailings water. The combined extracted NAs and algal oils can potentially be used as a low cost feedstock for the production of biodiesel. In this study, the feasibility of using NAs for the production of biodiesel was investigated using mixtures of canola oil and commercial NAs as model compounds.
Since NAs are a mixture of cyclic and acyclic carboxylic acids, the acid-catalyzed esterification of NAs without canola oil was investigated. The acid-catalyzed esterification reaction was carried out with methanol, and the influence of variables affecting the esterification process was examined. The experimental results showed that increasing temperature and catalyst concentration increased the reaction rate and final conversion of NAs to their corresponding methyl esters. The catalyst study showed that sulfuric acid had a more positive effect on the esterification reaction compared to p-toluene sulfonic acid. Additionally, an excess methanol:oil ratio had a negative effect on the esterification reaction due to the solubility of NAs in methanol.
The acid-catalyzed transesterification/esterification of mixtures of NA and vegetable oil (canola oil along with 5% NAs) with methanol was investigated at different operating conditions. The outcomes of these experiments showed that increasing temperature, sulfuric acid concentration, and methanol content had positive effects on the rate of reaction and final ester products.
The general conclusion of the thesis is that the conversion of NAs to useful products is indeed feasible and can be part of the solution to tar sands tailing pond remediation.
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Kling, Marcel Robert. "Synthesis of very long chain fatty acid methyl esters /." Title page, table of contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09phk65.pdf.
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Mayer, Júlia Gonçalves. "Comparação da análise de ácidos graxos TRANS em biscoito por cromatografia gasosa acoplada a espectrometria de massas (cg-em) e por espectroscopia no infravermelho com transformada de fourier e reflectância total atenuada (FT-IR-ATR)." Niterói, 2018. https://app.uff.br/riuff/handle/1/5892.
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JÚLIA GONÇALVES MAYER.pdf: 2883327 bytes, checksum: 6ae955490e1664e27d2c9669ad07a02c (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>Os métodos analíticos utilizados para medir o percentual de ácido graxo trans (AGT) em alimentos envolvem cromatografia em fase gasosa com detecção de ionização de chama (CG-DIC), espectrometria de massas (CG-EM) e espectroscopia no infravermelho com transformada de Fourier e refletância total atenuada (FT-IR-ATR). O presente estudo teve como objetivo investigar a viabilidade e a aplicabilidade do uso das técnicas de FT-IR-ATR, sem extração, com extração prévia da gordura e após hidrólise e metilação dos ácidos graxos, para avaliar o conteúdo de AGT em biscoitos recheados e comparar os resultados obtidos com os encontrados para a determinação de ácido elaídico pela técnica de CG-EM. Foram escolhidas 9 marcas de biscoitos recheados sabor chocolate e 1 pacote de gordura vegetal hidrogenada, para ser usada como padrão secundário para análise de AGT por FT-IR-ATR. As amostras foram analisadas, inicialmente, quanto aos seus conteúdos de umidade e lipídeos totais. Para todas as amostras não foi observada concentração de umidade superior a 6,03 g/100 g. Os lipídeos totais variaram de 12,51±0,58 a 23,84±0,09 g/100 g. A presença de AGT foi identificada por FT-IR-ATR pela visualização da banda próxima a 966 cm−1 e confirmada com adição de padrão às amostras. Ao analisar as amostras de biscoito homogeneizadas e sem outro preparo, não foi viável a utilização do método de FT-IR-ATR, visto que a absorção de radiação infravermelha de substâncias da amostra se sobrepõe à absorção na região das ligações duplas trans, o que demonstra que a matriz do alimento pode influenciar na análise. Quanto a presença dos AGT, ácido elaídico (C18:1, n-9 trans) foi identificado e confirmado em todas as amostras através de CG-EM. Ao comparar a quantificação pelos métodos CG-EM e FT-IR-ATR em amostras de extratos e na forma de ácidos graxos metilados (FAME), foram observadas concentrações baixas de ácido elaídico/ácidos graxos trans (de 0,03±0,01 a 0,86±0,01 g/100 g de biscoito) obtidas pelos diferentes métodos. Não foram encontradas diferenças significativas entre as concentrações de AGT determinadas pelos três métodos testados para oito das nove amostras analisadas. O presente trabalho mostrou que a técnica de FT-IR-ATR, analisando o extrato lipídico e as amostras em forma de FAME foi adequado para estimar os teores de AGT em biscoito recheado de chocolate, visto que proporciona uma análise mais rápida, com um menor número de etapas e menor consumo de reagentes em relação às análises por CG-EM<br>The analytical methods used to measure the percentage of trans fatty acids in foods involve gas chromatography with flame ionization detection (GC-FID), mass spectrometry (GC-MS) and attenuated total reflectance fourier transform infrared spectroscopy (ATR-FT-IR). The aim of the present study was to investigate the feasibility and applicability of ATR-FT-IR techniques, without extraction, with previous extraction of fat and after hydrolysis and methylation of fatty acids to evaluate the content of TFA in filled biscuits, and compare the results obtained with those found for the determination of elaidic acid by the CG-MS technique. Were chosen 9 marks of chocolate filled biscuit and 1 packet of hydrogenated vegetable fat to be used as a secondary standard for AGT analysis by ATR-FT-IR. The samples were initially analyzed for their moisture contents and total lipids. For all samples, no moisture content higher than 6.03 g/100 g. Total lipids ranged from 12.51 ± 0.58 to 23.84 ± 0.09 g/100g. The presence of TFA was identified by ATR-FT-IR through the visualization of the band near 966 cm−1 and confirmed with addition of standard to the samples. When analyzing the homogenized cookie samples and without further preparation, the use of the ATR-FT-IR method was not feasible because the absorption of infrared radiation from sample substances overlaps the absorption in the region of the trans double bonds, which demonstrates that the food matrix may influence the analysis. Regarding the presence of TFA, elaidic acid (C18: 1, n-9 trans) was identified and confirmed in all samples by GC-MS. When comparing quantification by GC-MS and ATR-FT-IR in samples of extracts and in the form of fatty acids methly esters (FAME), low concentrations of elaidic acid / trans fatty acids were observed (0.03 ± 0.01 to 0.86 ± 0.01 g / 100 g of biscuit) obtained by the different methods. No significant differences were found between the concentrations of TFA determined by the three methods tested for eight of the nine samples analyzed. The present study showed that the ATR-FT-IR technique, analyzing the lipid extract and the samples in the form of FAME, was adequate to estimate the TFA contents in chocolate filled biscuit, because it provides a faster analysis with a smaller number of steps and lower toxic chemicals in relation to GC-MS analyzes
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Chi, Lirong. "The production of methyl esters from vegetable oil/fatty acid mixtures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0006/MQ45896.pdf.
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Simpson, Michael J. "Synthesis of #DELTA#'9-desaturase inhibitors and related cyclopropenes." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239574.
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Kimmel, Tobias. "Kinetic investigation of the base catalyzed glycerolysis of fatty acid methyl esters." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97339174X.
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McWilliams, Kevin Michael. "Coordination of internal olefins, specifically fatty acid methyl esters (FAMEs), by transition metals." [Ames, Iowa : Iowa State University], 2007.
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Owston, Nathan Ashley. "Novel transition metal-catalysed syntheses of carboxylic acid derivatives." Thesis, University of Bath, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512253.
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This thesis describes the chemistry developed during a study of novel transition metalcatalysed reactions for the synthesis of carboxylic acid derivatives. Chapter 2 describes a novel protocol for the synthesis of primary amides from alcohols in one-pot where a metal complex mediates two fundamentally different catalytic processes. An iridium catalyst has been shown to be effective for the selective rearrangement of aldoximes into primary amides. In addition, an iridium-catalysed oxidation of activated alcohols via hydrogen transfer has been developed using an alkene as formal oxidant. These reactions have been combined in a sequential process affording good yields for a range of benzylic alcohols. An improved system for the rearrangement of aldoximes into amides using a new ruthenium catalyst is described in Chapter 3. Through a systematic program of optimisation excellent selectivity was achieved for a wide range of substrates at markedly reduced catalyst loading. Chapter 4 describes the development of a ruthenium-catalysed elimination reaction for the conversion of oxime ethers into nitriles. The application of this reaction to tandem and sequential reactions has been explored, albeit with limited success. Also, a method for the ruthenium-catalysed oxidation of alcohols using an electron-deficient alkene as hydrogen acceptor is described, and its application to a tandem oxidation process with a nitrogen nucleophile demonstrated. As an extension of the concept presented in Chapter 4, tandem oxidation processes with oxygen nucleophiles are the subject of Chapter 5. This strategy has been used for the oxidation of primary alcohols to their corresponding methyl esters in one-pot, with good yields obtained for a range of substrates. The use of water as a nucleophile in such a process has also been examined.
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Zhang, Wujuan. "Synthesis and Fragmentation Reactions of Linoleic Acid-Derived Hydroperoxides." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1189133862.
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Sekora, Nicholas Scott Lawrence Katheryn Kay Scott. "Identification of plant-parasitic nematodes using FAME analysis." Auburn, Ala, 2009. http://hdl.handle.net/10415/1806.
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Johansson, Katarina. "Fatty acid methyl esters as reactive diluents in solvent-borne thermally cured coil-coatings." Licentiate thesis, Stockholm, Chemical Science and Engineering, KTH, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4094.
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Hamid, Samiyah. "Production and purification of fatty acid methyl esters from plant oils of different origin." Thesis, University of Greenwich, 2011. http://gala.gre.ac.uk/8056/.
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Biodiesel production from plant oils has been studied since ca. 1900 and is now being widely adopted as a means to reduce carbon emissions in transport applications. Its properties are similar to those of fossil diesel fuel, thus allowing its use in diesel engines both pure and in mixtures with fossil diesel fuel. Biodiesel is obtained from vegetable oils or animal fats by a transesterification reaction whereby the triglycerides, contained in the oil or fat, react with a short chain alcohol in the presence of a catalyst. The products of the reaction are fatty acid methyl esters (biodiesel) and glycerol, obtained as two separate phases. However, current reaction efficiency using a homogeneous catalyst, such as sodium hydroxide, has various drawbacks. These include non-specificity leading to saponification, difficulty in isolating the catalyst from the fatty acid methyl esters, immiscibility of the catalyst with the reactants and incomplete transesterification. The aim of the research reported in this thesis is to provide a full description of the transesterification reaction. According to previously published methodologies, the transesterification of glycerol trioleate with sodium hydroxide should provide 97-98 % (w/w) conversion to the ester. However, the results reported, herein, indicated only 95.2% (w/w) ester content. To understand the differences in the results, the concentrations of sodium hydroxide and methanol were varied by using unrefined rapeseed oil. Results showed that the optimum reaction conditions to produce higher ester content (93.3% w/w) from unrefined rapeseed oil i.e. molar ratio of methanol/oil was 6:1 and 0.015 mol of sodium hydroxide at 60 min. The same results were obtained with various plants oils of different origin under similar reaction conditions, but no increase in the ester content was observed. The data suggested that the results were in accord with biodiesel specifications i.e. EN ISO 12937 and EN 14104. However, EN 14103 standard could not be met, perhaps due to the reversible nature of the reaction, higher acid value in the oil and other competing reactions of the triglycerides. It was not possible to achieve the ester content (%) according to EN 14103 standard if any moisture or free fatty acid was present in the oil or during the reaction. The failure to meet the required EN 14103 standards by using homogeneous catalytic systems paved the way for kinetics studies of the transesterification reaction. Heterogeneous catalysts offered the opportunity to study the reaction kinetics of the system because they can be separated rapidly from the reaction mixture by centrifugation. Various heterogeneous metal oxide catalysts were investigated. Strontium oxide was confirmed to be an effective catalyst but, contrary to expectations, similar catalytic activity was not observed for the other metal oxides. The experimental results obtained, by optimising reaction conditions using a heterogeneous catalyst were found to be 3% (w/w) SrO, 6:1 CH3OH/oil molar ratio at 120 min. Therefore, subsequent reactions were planned to carry out real-time kinetic studies using SrO as a catalyst. The application of refractometry allowed real-time kinetic studies of the transesterification reaction. The ester content obtained after transesterification were determined by gas chromatography and validated the results obtained by the refractometer method. This analytical method helped to improve the reaction conditions from 120 min to 90 min using 3% (w/w) SrO and 6:1 CH3OH/oil molar ratio to achieve 92% (w/w) ester content. During kinetic studies, using a heterogeneous catalyst, solubility issues were observed between oil, methanol and fatty acid methyl esters (FAMEs). Therefore, a phase solubility diagram was plotted to identify the miscible region. The transesterification reaction was conducted in the miscible region of a ternary phase diagram to overcome the phase limitation problems. The ester content obtained was higher than 98% (w/w) within 25-30 min depending on the concentration (% v/v) ratio of the reactants used. These results were encouraging in terms of using a heterogeneous catalyst since its use is limited to lower ester content (%) and longer reaction time.
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EL, JAZOULI MUSTAPHA. "Formation de liaisons carbone-carbone par l'intermediaire des imidothioesters : applications synthethiques." Caen, 1985. http://www.theses.fr/1985CAEN2016.
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Apres une etude de la metallation, suivie d'alkylation, de quelques imidothioesters satures, des reactions d'aldolisation dont la selectivite est examinee, sont realisees a partir d'un n-phenyl imidothioester. Les imidothioesters alpha -insatures dont la reactivite vis-a-vis de magnesiens et de lithiens est etudiee sont de bons accepteurs de michael. Par l'intermediaire des alkylthio-enaminates et d'une cetenimine issue de leur decomposition thermique, de nouvelles voies d'acces a des cetones dissymetriques, sont decrites a partir de n-phenyl imidothioesters satures et alpha -insatures. Synthese de cetones terpeniques et d'une pheromone
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Johansson, Katarina. "Thermally cured coil-coatings utilizing novel resins and fatty acid methyl esters as reactive diluents." Doctoral thesis, KTH, Fiber- och polymerteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4857.
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Solvent-borne thermally cured coil-coating resins contain large amounts of volatile organic solvents in order to obtain suitable flow for film application. This work describes how the expensive and environmental hazardous volatile organic solvent content of a solvent-borne thermally cured polyester/melamine coil-coating system can be reduced by introduction of fatty acid methyl esters (FAMEs) as reactive diluents and modification of the polyester binder resin. The evaluated reactive diluents, two rape seed methyl esters (RMEs), two linseed oil methyl esters (LMEs), and a tall oil methyl ester (TOME) have been evaluated both in a fully formulated clear-coat system and via model studies. Viscosity measurements of wet paint mixtures showed that formulations with hyperbranched polyester binder hold lower viscosity than conventional polyester binder resins and that FAME works as a diluent. Fully formulated clear-coats were cured under simulated industrial coil-coating cure conditions and in a convection oven at lower temperatures respectively. FAME increases the mobility of the system enhancing the film formation process. Free-standing clear-coat films were analyzed with Raman, carbon-14 dating, extraction, dynamic mechanical analysis, and visual observation. Incorporation of FAME could not be confirmed by Raman analysis. However, carbon-14 dating indicated the presence of FAME that could not be extracted from the films. The mechanical properties of the films were also affected by the addition of FAMEs, oven temperature, choice of co-solvent, and flash-off period. Conventional film characterization tests on substrate supported coatings indicated that binder resin structure and cure conditions affect the final film properties. Model studies were performed to clarify how FAME can chemically react through transesterification with the hydroxyl-groups of the polyester. The transesterification reaction between different FAMEs and primary alcohols with and without tertiary hydrogen was monitored with 1H-NMR and real time IR. Evaporation and side reactions, e.g. alkene reactions, are competing factors to the transesterification reaction. The study showed that fatty acid structure, reaction time, and temperature affect the transesterification conversion, degree of side reactions, and choice of catalyst. A pigmented fully formulated polyester/melamine formulation with a reactive diluent was cured at full scale in an industrial coil-coating production facility. Evaluation of the final film properties showed that the coating fulfills the specification of conventional polyester/melamine coil-coating systems.<br>QC 20100817
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Negi, Devender Singh. "Base catalyzed glycerolysis of fatty acid methyl esters: investigations towards the development of a continuous process." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980493404.
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Falahati, Hamid. "The Characterization of Bimodal Droplet Size Distributions in the Ultrafiltration of Highly Concentrated Emulsions Applied to the Production of Biodiesel." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/19585.
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A non-reactive model system comprising a highly concentrated and unstable oil-in-water emulsion was used to investigate the retention of oil by the membrane in producing biodiesel with a membrane reactor. Critical flux was identified using the relationship between the permeate flux and transmembrane pressure along with the separation efficiency of the membrane. It was shown that separation efficiencies above 99.5% could be obtained at all operating conditions up to the critical flux. It was observed that the concentration of oil in all collected permeate samples using the oil-water system was below 0.2 wt% when operating at a flux below the critical flux. Studies to date have been limited to the characterization of low concentrated emulsions below 15 vol.%. The average oil droplet size in highly concentrated emulsions was measured as 3200 nm employing direct light scattering (DLS) measurement methods. It was observed that the estimated cake layer thickness of 20 to 80 mm was larger than external diameter of the membrane tube i.e. 6 mm based on a large particle size. Settling of the concentrated emulsion permitted the detection of a smaller particle size distribution (30-100 nm) within the larger particles averaging 3200 nm. It was identified that DLS methods could not efficiently give the droplet size distribution of the oil in the emulsion since large particles interfered with the detection of smaller particles. The content of the smaller particles represented 1% of the total weight of oil at 30°C and 5% at 70°C. This was too low to be detected using DLS measurements but was sufficient to affect ultrafiltration. In order to study the critical flux in the presence of transesterification reaction and the effect of cross flow velocity on separation, various oils were transesterified in another membrane reactor providing higher cross flow velocity. higher cross flow velocity provides better separation by reducing materials deposition on the surface of the membrane due to higher shearing. The oils tested were canola, corn, sunflower and unrefined soy oils (Free Fatty Acids (FFA< 1%)), and waste cooking oil (FFA= 9%). The quality of all biodiesel samples was studied in terms of glycerine, mono-glyceride, di-glyceride and tri-glyceride concentrations. The composition of all biodiesel samples were in the range required by ASTM D6751 and EN 14214 standards. A critical flux based on operating pressure in the reactor was reached for waste cooking and pre-treated corn oils. It was identified that the reaction residence time in the reactor was an extremely important design parameter affecting the operating pressure in the reactor.<br>Natural Sciences and Engineering Research Council of Canada (NSERC)
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Scholten, Matthew John. "Enzymatic and chemical modification of fatty acid methyl esters: enzymatic catalysis of methyl linoleate using soybean lipoxygenase and chemical catalysis of methyl oleate Using Hypobromination." Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/735.
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Vegetable oils are a cheap and abundant chemical feedstock which can be readily broken down into fatty acid methyl esters (FAMEs) by transesterification using methanol and a base catalyst. These FAMEs contain reactive unsaturated double bonds which can be targeted for modification. In this study, enzymatic and chemical modifications of the unsaturated double bonds of FAMEs are explored with the goal of producing higher value products. Specifically the enzymatic modification of methyl linoleate using soybean lipoxygenase and the chemical modification of methyl oleate using hypobromantion are studied.
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Revill, John Austin Timothy. "A study of the solution photophysics of the isomeric aminobenzoic acids, N, N-dimethylaminobenzoic acids and their methyl esters." Thesis, University of Central Lancashire, 1993. http://clok.uclan.ac.uk/20170/.
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The solution photophysics of the isomeric aminobenzoic acids and N,Ndimethylaminobenzoic acids and their methyl esters were studied under a variety of conditions of solvent, pH, concentration and temperature. The most straightforward behaviour was obtained when the amino or N,N-dimethylamino substituent was in the meta- position relative to the carboxylic add or ester function. The amino compounds absorb with a peak between 300 and 325 nm depending on solvent, their fluorescence peaks lie between 350 and 410 rim. The corresponding N,N-dimethylamino compounds usually absorb and fluoresce some 20 - 30 rim to the red of these wavelengths. Both protonation and deprotonation of the ground state molecules takes place under weakly acidic conditions with pKi, values of approximately 3.0 and pK a values of approximately 5.0 being obtained. The observed variation in the fluorescence of the meta isomers with pH is largely caused by ground state equilibria. Förster cycle calculations suggest that the excited state pK a is little changed from the ground state whereas pKC is much smaller. This is in good agreement with the observed fluorescence data and the nature of the excited nglet state (usually some 10 -20 ns) than is seen for the other isomers. The fluorescence intensity of the meta- isomers was observed to rise with decreasing temperature, although this could possibly be attributed to absorbance changes. The photophysics of the corresponding ortho compounds is complicated by steric and hydrogen-bonding interactions especially in the compounds containing an N,N-dimethylamino group. The increased interaction between the two substituent groups leads to an increase in extinction coefficient and fluorescence quantum yield and a decrease in fluorescence lifetime for 2-aminobenzoic acid and its methyl ester compared to the meta derivatives. Spectral band positions, pK values and the effect of temperature on the fluorescence are similar in the two sets of compounds. The 2-N,Ndimethylamino compounds do not parallel the corresponding meta- derivatives due to steric hindrance and intra-molecular hydrogen bonding. These cause weak, blue shifted absorptions and low fluorescence quantum yields. There was no evidence found in this work for the presence of a zwitterionic species in the absorption properties of 2-N,N-dimethylaminobenzoic acid. The photophysical properties of 4-aminobenzoic acid and its methyl ester are in many ways very similar to those of the corresponding orthosubstituted compounds. However the same certainly cannot be said for 4-N,Ndimethylaminobenzoic add and its methyl ester. These two compounds exhibit anomalous fluorescence in the form of two fluorescence bands in some solvents. The appearance of this anomalous fluorescence is both concentration and solvent composition dependent. Various mechanisms to explain these observations were tested; excimer, exciplex, TICT state and ground state dimer formation. The latter was found to be in best accord with the properties of these molecules, but it was clear that in binary solvent mixtures such as hexane / acetonitrile and acetonitrile / water other mechanisms could also be involved.
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Babajide, Omotola Oluwafunmilayo. "Optimisation of biodiesel production via different catalytic and process systems." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3380_1365754281.
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<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<br>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 º<br>C with a methanol: oil ratio of 6:1 and 1.0 KOH % wt/wt of oil<br>while the optimum reaction conditions for the used oil (WCO) was observed at a reaction time of 90 min at 60 º<br>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 º<br>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<br>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 º<br>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 °<br>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 º<br>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<br>these catalyst materials subsequently applied sucessfully as solid base catalysts in the production of biodiesel.</p>
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Moreau, Laurent. "Optimisation d'un procédé de biosynthèse d'esters à chaines hydrocarbonées courtes : mise en oeuvre d'un réacteur." Grenoble 1, 1996. http://www.theses.fr/1996GRE10090.
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Dans l'industrie agro-alimentaire, les pertes de gout et d'odeur dues aux procedes de fabrication doivent etre compensees par des apports d'aromes. Dans cette optique, des esters naturels peuvent etre biosynthetises par le biais de lipases. Le procede de bioconversion d'esters par catalyse enzymatique mis au point a ete developpe a partir de l'acetate de methyle, ester particulierement difficile a bioconvertir, pour faciliter ensuite l'extension du procede a d'autres esters. Differentes etudes ont ete realisees afin d'optimiser successivement les differentes phases que sont la bioconversion en reacteur ferme, la separation, la purification et le recyclage du solvant et du catalyseur. Un procede permettant la bioconversion continue de l'ester a ensuite ete developpe. L'extension de nos travaux a un ester different a ete realisee par le biais du caproate de methyle. L'optimisation des differentes etapes a ete tres simplifiee par le travail prealable sur l'acetate de methyle. La production en continu par l'intermediaire du procede prealablement developpe a permis d'obtenir 60 grammes d'ester naturel par heure. Les possibilites de ce reacteur sur le plan industriel sont donc reelles, aussi bien au niveau de sa capacite de production que de ses possibilites d'extension a d'autres esters
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Bule, Maria João Galvão Morgado. "Produção de biodiesel por catálise enzimática em sistemas descontínuo e contínuo a partir de óleo de cardo." Master's thesis, ISA, 2014. http://hdl.handle.net/10400.5/6804.
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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia<br>The aim of this study is the biodiesel production from cardoon seed oil (Cynara cardunculus, L.) by enzymatic catalysis in batch and continuous systems.
The biodiesel (fatty acid methyl esters - FAME) was obtained by transesterification of the crude cardoon oil with methanol, in a biphasic organic/aqueous system, catalyzed by the lipase/acyltransferase from Candida parapsilosis immobilized in synthetic resins (Accurel MP1000 and Lewatit VP OC 1600).
This enzyme, when biphasic media, catalyses preferentially transesterification over hydrolysis, conversely to the behaviour of conventional lipases.
In batch system, the highest FAME yield (about 97%) was obtained with the enzyme immobilized in Lewatit VP OC 1600 after 24h of reaction, with an oil concentration of 10% (m/v) in the emulsion.
The Fame production system was implemented in a packed-bed continuous reactor. The highest FAME yield (about 20%) was obtained with the enzyme immobilized in Accurel MP 1000 with an oil concentration of 20% (m/v) in the emulsion.
In this essay, the enzyme demonstrated a good operational stability, remaining active about 15 days, when the FAME production stopped.
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Lane, Matthew S. "THE EFFECT OF GLYPHOSATE ON SOIL MICROBIAL COMMUNITIES." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1301068421.
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Lee, Lisa S. "Design of porous solids from 2-D and 3-D coordination frameworks utilizing imidazolylbenzoic acids and esters." Digital WPI, 2008. https://digitalcommons.wpi.edu/etd-theses/1017.
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"The investigation through design and synthesis of metal-organic frameworks was conducted in an effort to create new types of porous crystalline solids. The supramolecular chemistry and crystal structures of six novel frameworks (1-Cd, 2Cd, 1-Cu, 2a-Cu, 2b-Cu, 3-Cu) are reported. We are targeting porous solids composed of the transition metals Cu2+ and Cd2+ with three related families of organic molecules: Ethyl 4-(1H-imidazol-1-yl)benzoate, 4-(1H-benzo[d]imidazol-1-yl)benzoic acid, and Ethyl 4-(2-methyl-1H-imidazol-1-yl)benzoate. These molecular building blocks self assemble via metal coordination into coordination polymers that form a variety of 1-D, 2-D, and 3-D architectures. The networks are comprised of M•••O and M•••N bonds that coordinate into different geometrical arrangements dependent on steric hindrance and the metal ions that are used. The frameworks synthesized display porous behavior using weight measurements that are also seen to be reversible in some cases using atmospheric reuptake of guest molecules from growth solution. The uptake of rhodamine b was examined for the framework 3-Cu."
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Louis, Kévin. "Synthèse et fonctionnalisation d'aldéhydes issus de la coupure d'esters gras insaturés." Thesis, Poitiers, 2013. http://www.theses.fr/2013POIT2290/document.
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La valorisation du carbone renouvelable joue un rôle croissant dans l'industrie chimique. Ces travaux rapportent l'utilisation d'huiles végétales comme matières premières en substitution de celles d'origine fossiles pour la synthèse de monomères bio-sourcés destinés à la production de polyesters ou de polyamides.La production du 9 oxononanoate de méthyle, comme molécule plateforme, à partir d'esters méthyliques d'huile de colza a été réalisée par coupure oxydante (ozonolyse) sans solvant à température ambiante, suivie d'une réduction des intermédiaires par hydrogénation catalytique sous pression de H2 et de Pd(5)/C. Ainsi, le rendement en aldéhyde-ester est de 92%. Ce procédé a été appliqué à la synthèse de molécules plateformes avec des longueurs de chaînes de 9 à 13 atomes de carbone. Une matière première renouvelable, des conditions de réaction douces, le recyclage du catalyseur et des co-produits non toxiques et valorisables ont permis de développer un procédé durable plus respectueux de l'environnement. La réduction de la fonction aldéhyde a été menée par hydrogénation catalytique, à 50°C dans le méthanol, pour former l'alcool-ester correspondant. Le nickel de Raney ainsi que le Pd(5)/C offrent des rendements en 9-hydroxynonanoate de méthyle supérieurs à 90 %, mais le premier catalyseur conduit à un temps de réaction plus court. L'amination réductrice de la fonction aldéhyde a été menée avec succès à partir de NH3 gazeux et de Pd(5)/C, à 50°C dans le méthanol, pour conduire majoritairement à la synthèse de l'amino-ester primaire. La quantité de NH3(g) influence la sélectivité et au moins trois équivalents sont nécessaires pour limiter la formation d'amino-ester<br>A high interest has been devoted to the use of renewable carbon in the chemical industry. The goal of this work is the substitution of fossil oils by vegetable oils to synthesize bio sourced monomers for polyesters and polyamides production. The synthesis of methyl 9-oxononanoate as a platform molecule from fatty acid methyl esters of rapeseed oil was carried out in solvent free ozonolysis at room temperature. Intermediary ozonides was reduced to aldehydes by catalytic hydrogenation under H2 pressure and in the presence of Pd(5)/C catalyst giving a 92% carbonyl yield. This process was applied to a wide range of unsaturated esters with a chain length within 9 and 13 carbon atoms. This process allows the selective conversion of renewable materials to value added chemicals, in mild conditions and in the presence of a recyclable catalyst. Moreover, the co products are non toxic and valuable. Hydrogenation of aldehyde group was performed in the presence of methanol at 50°C under hydrogen pressure. Raney Nickel and Pd(5)/C exhibit a yield to methyl 9 hydroxynonanoate higher than 90%. Reductive amination of the aldehyde functional group was investigated with success in the presence of NH3(g) and Pd(5)/C at 50°C in methanol to produce primary amino ester. The amount of ammoniac is directly correlated to the selectivity of the reaction. As a consequence a minimum amount of 3 eq. of ammoniac is required to avoid the formation of secondary amino-ester
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Silva, Raquel Filipa Maia da. "Produção de Biodiesel por catálise enzimática a partir de óleo de cardo." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4073.
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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia<br>This work aimed the production of biodiesel from cardoon seed oil (Cynara cardunculus L.) by enzymatic catalysis.
The oil was extracted from cardoon seeds from two different crops, 2007 and 2009, and had a free fatty acid (FFA) content of 4.5% and 1.6%, respectively. The effect of FFA content in the enzymatic reaction kinetics was, therefore, investigated.
The biodiesel (fatty acid methyl esters - FAME) were obtained by transesterification of crude oil whit methanol in a biphasic organic/aqueous system in the presence of a biocatalyst (enzyme). The lipase/acyltransferase from Candida parapsilosis was used in free form and immobilized in syntetic resins (Accurel MP1000 and Eupergit C) at different concentrations from 0.13% to 2.65% in the reaccion.
Using an amount of 0.28% of enzyme in the free form, a maximum yield of 97% of FAME was obtained after 24h of reaction. In the production of fatty acid methyl esters using immobilized lipase/acyltransferase a lower yield of approximately 40% was obtained, but the recovery and reuse of the enzyme in different studies is possible. The FFA content in cardoon oils did not affect enzymatic catalysis
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Timmons, Michael Douglas. "EXPLORATIONS IN HOMEOVISCOUS ADAPTATION AND MASS SPECTRAL ANALYSIS OF MEMBRANE LIPIDS." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/74.
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The focus of this dissertation is centered on the mass spectral analysis of lipids and changes occurring in keeping with the concept of homeoviscous adaptation [1]. Homeoviscous adaptation is the process of modification of membrane lipids in response to environmental stimuli [1]. Dissertation investigations applied this concept to prokaryotic and eukaryotic organisms, and expanded the perception of environmental factors from exogenous organic solvents to intracellular environment.
The field of lipidomics deals with the analysis of phospholipid and fatty acid components of membranes the changes that occur due to environmental stimuli and their biological significance [2-6]. The high sensitivity of mass spectrometry (MS) is an ideal tool for lipidomics allowing detection, quantification and structural elucidation [6]. Coupling of a mass spectrometer to a chromatographic system, such as gas chromatograph (GC), allows the separation of fatty acid methyl esters analytes prior to analysis [7].
The research investigations that comprise this dissertation are divided into three interrelated projects. The first project involved the analysis of composition and structure of Clostridium thermocellum membranes from wild-type and ethanol-adapted strains in response to adaptation of cultures to growth in ethanol. The hypothesis being that adaptation of cultures to growth in ethanol would result in compensatory change to the membrane composition.
Rat mitochondrial fatty acid profiles isolated from brain, liver, kidney and heart tissues were compared. The hypothesis being that differences in cellular environments found among various tissues would be reflected in the mitochondrial membrane composition. These data support the concept that variations to the lipid content of neurological mitochondria may increase susceptibility to the products of oxidative stress.
Lastly, changes in neurological mitochondria as a function of Alzheimer’s disease progression were studied. The hypothesis being that changes to the mitochondrial lipidome would be significantly reflected during advanced stages of AD, in addition to being more prevalent in regions displaying greater pathology.
The three interrelated projects increased our understanding of the boundaries established by the concept of homeoviscous adaptation. Project specific hypotheses were supported by data obtained from these investigations.
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Fabrello, Chantal. "Etude et realisation d'une preforme de fibre optique en polymere a base de methacrylate de methyle." Toulouse 3, 1986. http://www.theses.fr/1986TOU30127.
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Stewart, Gaynelle. "Engineering Saccharomyces ceresisiae for the Secretion of an Extracellular Lipase." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/577.
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Developing microbial systems capable of converting low cost lipids into value added products depends on the ability to acquire substrates from the growth media. Saccharomyces cerevisiae can acquire free fatty acids from the growth media and a portion of these lipids can be converted into new lipid products. However, they cannot acquire complex lipids from the growth media unless a nonspecific lipase is included. To circumvent lipase addition, we are genetically engineering S. cerevisiae to secrete a lipase into the growth media. We selected the LIP2 gene from Yarrowia lipolytica, which encodes a nonspecific lipase. Several modifications were made to the LIP2 gene to improve processing. Results identified strains secreting the most lipase. From these results, high producing strains were inserted into an oil inducible vector. Halo assays confirmed lipase secretion, while measuring the fatty acid composition confirmed triacylglycerol breakdown, and yeast uptake of the free fatty acids released.
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Cai, Xiaoshuang. "Production of carbonated vegetable oils from a kinetic modeling to a structure-reactivity approach Structure-reactivity : comparison between the carbonation of epoxidized vegetable oils and the corresponding epoxidized fatty acid methyl ester Aminolysis of cyclic-carbonate vegetable oils as a non-isocyanate route for the synthesis of polyurethane: a kinetic and thermal study Influence of ring‐opening reactions on the kinetics of cottonseed oil epoxidation Investigation of the physicochemical properties for vegetable oils and their epoxidized and carbonated derivatives Influence of gas-liquid mass transfer on kinetic modeling : carbonation of epoxidized vegetable oils." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR05.
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La valorisation de la biomasse et du dioxyde de carbone est à présent considérée comme une solution aux problèmes environnementaux du réchauffement climatique et l'épuisement des réserves de pétrole. Ainsi, les huiles végétales ont attiré l'attention croissante des milieux universitaires et industriels, comme une source de biomasse potentielle renouvelable qui peut être appliquée à la production de substitut fossile pour un développement durable, due à leurs caractères renouvelables, durables, biodégradables. De plus, cette biomasse est disponible avec une énorme quantité. Durant des décennies de recherches, les processus d'époxydation et de carbonatation sont deux méthodes d'application populaires pour la valorisation des huiles végétales. La conversion des huiles végétales en huiles époxydées est définie par une conversion d'un composé insaturé en un groupe époxyde. Jusqu'ici, l'oxydation de Prileschajew est la méthode de synthèse plus efficace pour la possible industrialisation du processus d'époxydation de huiles végétales, qui est une manière conventionnelle bien connue à utiliser comme processus de production commerciale. Ce type d'époxydation utilise l'acide percarboxylique comme transporteur d'oxygène qui est formé in situ dans la phase aqueuse, et ensuite époxyde les groupes insaturés des huiles végétales en groupes époxyde. Cependant, cette méthode présente une réaction secondaire d'ouverture du cycle du groupe époxyde au cours du processus. Donc, les conditions du procédé d'époxydation doivent être optimisées afin de minimiser les réactions d'ouverture de cycle. Des paramètres de réaction, y compris la concentration en catalyseur acide (acide sulfurique), réactifs (eau, groupe époxyde, peroxyde d'hydrogène, acide acétique) et la température de réaction, ont été discutés dans cette étude pour l'époxydation et réaction d'ouverture de cycle des huiles végétales. Au cours de la modélisation cinétique, les constantes cinétiques associées pour les réactions d'ouverture du cycle ont été estimées. En se basant sur ce modèle, les réactions d'ouverture du cycle époxyde par les acides acétique et peracétique sont plus rapides que celles de l'eau et du peroxyde d'hydrogène. Un réacteur en mode semi-fermé, avec addition du peroxyde d'hydrogène et de l'acide sulfurique, est la configuration la plus appropriée pour la production d'huiles végétales époxydées. Pour déterminer les conditions optimales et passer à échelle industrielle dans les procédés d'époxydation et de la carbonation, il faut connaître différentes propriétés physicochimiques telles que la viscosité, la densité, l'indice de réfraction, la capacité thermique spécifique et les évolutions de ces données avec la température. Cependant, aucune information sur ces propriétés est disponible dans la littérature. Pour cette étude, l'évolution de ces propriétés ont été déterminées pour trois huiles végétales et leurs dérivés époxydées et carbonates (l'huile de coton, l'huile de lin et l'huile de soja) avec la température et leur composition. La densité et l'indice de réfraction ont été trouvé linéairement dépendant de la température pour les huiles étudiées. La relation entre la contrainte de cisaillement et le taux de cisaillement dans l’étude de viscosité, indique que ces huiles sont des fluides newtoniens. Il a été démontré que la capacité thermique spécifique suit une équation polynomiale du second ordre avec la température. Sur la base de ces résultats, il a été démontré que certaines corrélations pourraient être utilisées pour prédire les évolutions de ces propriétés physicochimiques à différentes compositions et températures<br>Nowadays, biomass and carbon dioxide valorization are considered as a helpful solution to the environmental issues of global warming and the depletion of petroleum reserves. Thus, vegetable oils have attracted increasing attention of academic and industrial communities, as one of the potential renewable biomass that can be applied to the production of fossil substitute for sustainable development, owning to their advantages of renewable, sustainable, biodegradable, and universally available with huge feedstock. Among decades of researches, epoxidation and carbonation processes are two popular application methods for vegetable oil valorization. The conversion of vegetable oils into epoxidized ones is defined by a conversion of unsaturated compound into an epoxide group. So far, the potential application for the production of epoxidized oil in the industrial is the Prileschajew oxidation, which is a wellknown conventional way to be used as the commercial production process. This type of epoxidation uses percarboxylic acid as an oxygen carrier, which is formed in situ in the aqueous phase, and then epoxidize the unsaturated groups on the vegetable oils into epoxide groups. During the process, however, this method presents side reaction of ring-opening of the epoxide group. Therefore, the selective epoxidation process conditions need to be optimized in order to minimize the ring-opening reactions. In this study, process parameters including the concentration of acid catalyst (sulfuric acid), reactants (water, epoxide group, hydrogen peroxide, acetic acid) and the reaction temperature have been discussed for the epoxidation and ring opening of vegetable oils. During the kinetic modeling stage, the related kinetic constants for the ring opening reactions were estimated. Based on this model, the ring opening by acetic and peracetic acids was found to be faster than by water and hydrogen peroxide. A semibatch reactor, where hydrogen peroxide and sulfuric acid were added, was found to be the most suitable configuration. To determine the optimum operating conditions and scale up the epoxidation or carbonation processes, it requires the database of different physicochemical properties, i.e. viscosity, density, refractive index, or specific heat capacity and the evolutions of these properties with the temperature. However, this information is absent in the literature. For this study, the evolution of these properties with temperature and compositions (double bond, epoxide and carbonated groups concentration) was determined for three vegetable oils and their corresponding epoxidized and carbonated forms (cottonseed oil, linseed oil and soybean oil). Density and refractive indices of these oils were found to vary linearly with temperature. Based on the measurement of changes in viscous stresses with shear rates, these oils were found to be Newtonian fluids. It was demonstrated that specific heat capacity follows a polynomial equation of second order with temperature. Based on these results, it was demonstrated that some correlations could be used to predict the evolutions of these physicochemical properties at different composition and temperature based on the knowledge of the property of the pure compounds
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Coetzee, Jacorien. "Towards new catalytic systems for the formation of methyl methacrylate from methyl propanoate." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2585.
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The two stage Lucite Alpha Process for the industrial manufacturing of methyl methacrylate (MMA) represents one of the most efficient technologies currently available for the large scale production of this important chemical commodity. The second stage of this process, which involves the condensation of methyl propanoate (MeP) with formaldehyde over a heterogeneous fixed bed catalyst, however, still shows great scope for improvement. Herein the development of a novel homogeneous catalytic system that would promote the condensation of either propanoic acid or MeP with formaldehyde is explored. Since C–C bond forming reactions which proceed via C–H activation pathways typically display high atom efficiency, our efforts were particularly focussed on employing a functionalisation strategy that is mediated by C–H activation. In the case of propanoic acid, the possibility of achieving regioselective α-methylenation by linking the substrate to phosphorus was evaluated. Thus, a series of acyloxyphosphines and acylphosphites derived from either propionic acid or phenylacetic acid was prepared and, where stability allowed, fully characterised. Some of the resultant simple mixed anhydrides posed problems relating to their stability, and the stabilisation of such ligand systems by using electronic and / or steric effects was therefore explored. In addition, the coordination chemistry and in solution behaviour of Rh(I) and Ru(II) complexes containing these ligands was examined. Similar to the free ligands, complexes derived from these mixed anhydrides rearranged in solution via a number of decomposition pathways, with the specific pathway dependent on the nature of the auxiliary ligands. For most of these complexes, however, ligand decarbonylation was the route of preference for decomposition. Despite the instability of these complexes, a selection of Rh(I) mixed anhydride complexes were assessed for their potential as C-H activation catalysts in reactions aimed at the α-methylenation of saturated carboxylic acids. Furthermore, the stabilisation of Rh(I) mixed anhydride complexes with chelating auxilary ligands, such as bisphosphines or N-substituted diphosphinoamines, was explored. In particular, a series of new Rh(I) mixed anhydride complexes containing dppe, dppb and dppbz as secondary ligands were prepared and the effects of these secondary ligands on the in solution stability of these complexes assessed. As MeP represents the final product in the first stage of the Alpha process and not propanoic acid, the utilisation of PNP iridium pincer complexes in the regioselective sp³ C–H activation of MeP and related esters was also examined. The factors that govern the regioselectivity of such reactions were of great interest to us and, in particular, the effects of water on the reactivity and regioselectivity of these reactions were explored. For MeP, preferential C–H activation of the methoxy group was found to proceed under anhydrous conditions and the catalytic functionalisation of this site with ethene using this activation approach was considered. Formaldehyde, employed in the second stage of the Alpha process, is a difficult substance to manufacture and handle, especially on a large scale. A preliminary study on the in situ production of anhydrous formaldehyde via the catalytic dehydrogenation of methanol was therefore performed. During this study, catalytic systems based on carbonate salts and / or transition metal complexes were considered. In the hope of reducing the number of steps required in the production of MMA, a new one-pot cascade reaction for the indirect α-methylenation of MeP with methanol was developed. Although the production of MMA using this system only proceeded with low efficiency, the obtained results serve as an important proof of concept for future developments in this area. Finally, the capacity of a series of simple bases to catalyse the condensation of MeP with formaldehyde was assessed as part of a fundamental study directed towards determining the factors that govern the efficiency of this reaction. In addition, the extent to which each base effects the deprotonation in the α-position of MeP was determined with the aid of deuterium labelling experiments. Similarly, using sodium propanoate as model base a rough estimate of the kinetics of deprotonation could be made based on the degree of deuterium incorporation over time. These studies suggested that the low efficiency of this condensation reaction is not caused by ineffective deprotonation but rather by the weak nucleophilicity of the generated carbanion. For this reason, attempts to increase the electrophilicity of formaldehyde through Mannich-type condensations reactions involving secondary amine and carboxylic acid additives were made.