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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Microwave and ionic liquid to enhance the yield of biodiesel study

Hsu, kuo-Hsiang 23 June 2010 (has links)
Soybean oil, palm oil and waste cooking oil as feedstock were used to measure the effects of different heating methods, reaction time, molar ratio of methanol to oil, temperature, power, catalyst type and catalyst concentration on the biodiesel yield in this study. Additionally, reducing reaction time for the transesterification reaction used microwave heating to make more complete. The optimized operating conditions of conventional heating used palm oil, concentration for 0.75 wt% sodium methoxide, molar ratio of methanol to oil for 6:1, reaction time for 90 min and reaction temperature for 60 ¢J offered the best yield of 98.1%. the microwave heating used palm oil, concentration for 0.75 wt% sodium methoxide, molar ratio of methanol to oil for 6:1, reaction time for 3 min and power for 750 W offered the best yield of 99.5% Used soybean oil and palm oil as biodiesel feedstock production, its yield was higher than the waste cooking oil. This reason is caused by composition complex and high viscosity of waste cooking oil compare with pure vegetable oil. The catalyst of sodium methoxide is higher effective than sodium oxide used in transesterification reaction, because the reaction process will not formation of water and saponification. Use ionic liquid [Pyr12CN][Cl], [MorEtH][HSO4], [MorMeMe][MeSO4], [PyrMeH][HSO4] and [MorMeEt][EtSO4] as biodiesel catalyst, the optimized operating conditions of concentration for 2.00 wt% [Pyr12CN][Cl], molar ratio of methanol to oil for 6:1, reaction time for 6 min and power for 750 W offered the best yield of 98.1%.
2

Toward Sustainable Process Development for Biodiesel Production

Martinez-Guerra, Edith Lorena 07 May 2016 (has links)
Resource-efficient technologies are essential for economically viable biodiesel production. This work focuses on conversion of microalgal lipids and vegetable oils into fatty acid alkyl esters or biodiesel. Transesterification of waste cooking oil (WCO) and extractive-transesterification of wet microalgal biomass were investigated using microwave and ultrasound irradiations through several process parametric evaluation studies to elucidate the effects of different alcohols and catalyst types (homogeneous and heterogeneous), reaction time, and reaction temperatures. First, a brief overview of process steps involved in microalgal biodiesel production and associated energy consumption and research needs were discussed. Next, energy analysis of microalgal biocrude production via extractive-transesterification under microwave and ultrasound irradiations (individually) was performed. Then, the synergistic effect of microwave and ultrasound irradiations on extractive-transesterification of microalgal lipids was evaluated through a process optimization study using response surface methodology to determine the best process conditions. For this study, a maximum biocrude conversion of 51.2% was obtained when 20 g of algal paste was treated with 30 mL methanol, 1 wt.% catalyst, 7 min reaction time, and 140 W for MW and US (280 W total). Further, biocrude yield kinetics study revealed that the activation energy for this reaction was around 17, 298 J mol-1 K-1. A series of experimental studies were conducted to understand the roles and effects of various process related conditions including the power output and power density of microwave and ultrasound irradiations in biodiesel production. The two non-conventional heating techniques were compared for their process intensification effects. Ultrasound was applied either in continuous or pulse mode. Pulse sonication was found to be more suitable for simple transesterification reaction of WCO with a 98% biodiesel yield in 2.5 min (9:1 methanol to oil ratio, 1.25% catalyst, and 150 W power output) over 82% yield for continuous sonication under the same conditions. Followed by this, a detailed study was conducted to determine optimum pulse (ON and OFF time) sonication conditions. A 99% conversion yield was obtained for a pulse ON-OFF combination of 7s-2s. Additionally, the effect of different alcohols (ethanol, methanol, and ethanol-methanol mixtures) using pulse sonication was evaluated.
3

Highly efficient procedure for the synthesis of biodiesel using ionic liquid as catalyst

Lin, Jia-fang 16 July 2012 (has links)
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.
4

Promoting Sustainability in the Energy Sector in Nepal-with a Focus on Biodiesel Fuel

KC (Chhetri), Arjun Bahadur 27 August 2012 (has links)
This study analyzes the sustainability of various energy sources including micro hydro power and biodiesel in the context of Nepal. The main focus is on the development of biodiesel fuels from non-edible oil resources including waste cooking oil, jatropha and soapnut oil feedstocks grown on the marginal lands of Nepal. Biodiesel fuel samples were prepared by acid and/or base catalyst transesterification. Both single stage and dual stage transesterification processes were employed depending on the free fatty acid content of the oil feedstock. The oil to biodiesel conversion rate and total yield were monitored. The quality of the biodiesel fuels including viscosity etc was confirmed by an external laboratory and all fuels met the ASTM fuel quality requirements. Canola, jatropha and soapnut biodiesel fuels were tested to determine some atomization properties - density, surface tension and viscosity - at elevated temperatures and pressures. The density of three biodiesel fuels and diesel were determined up to 523 K and 7 MPa using a capacitance type densitometer. The results showed a linear relationship with temperature and pressure over the measured range. The experimental data were well within the range of canola and other biodiesel fuels found in the literature. Kay’s mixing rule was used to predict the density of some biodiesel blends and the results were found to be in agreement with less than 5% error with the measured data. The surface tension was measured using a pendant drop apparatus for all three biodiesel and diesel fuels for temperatures and pressures up to 473K and 7 MPa. Results showed a linear relationship with temperature as well as with pressure. Temperature has a higher effect on surface tension than pressure. The viscosity of all three biodiesel and diesel fuels were measured using a torsional vibration viscometer up to 523 K and 7 MPa. Results showed that the viscosity-temperature relationship of all three biodiesel fuels tested followed a modified Andrade equation which was also applicable when temperature and pressure were both applied simultaneously. The measured and regressed kinematic and dynamic viscosities obtained were comparable with values in the literature. / This thesis is focused on sustainability analysis of alternative fuels in Nepal and presents the resullts of the tests on fuel and atomization characterisation of different biodiesel feedstocks including canola, jatropha, soapnut and waste cooking oil. A new model to evaluate sustainability of renewable alternatives energy resources has been developed and tested.
5

Selection, development and design of a continuous and intensified reactor technology to transform waste cooking oil in biodiesel and biosourced formulations / Sélection, développement et conception d'un réacteur continu et intensifié pour la transformation d'huiles végétales usagées en biodiesel et dérivés biosourcés

Mazubert, Alex 27 November 2014 (has links)
L'objectif de cette thèse est de proposer un réacteur continu et intensifié pour la transformation d’huiles végétales de récupération en produits ou intermédiaires qui seront ensuite utilisés ou formulés en applications destinées au BTP. Ce travail s’inscrit dans le cadre du FUI AGRIBTP, projet de recherche collaboratif qui a pour finalité la création d'un outil industriel de valorisation des sous-produits de l'agro-industrie. Le réacteur se veut pluri-réactionnel, c’est-à-dire adapté et efficace pour réaliser les réactions de transestérification ou d’estérification par le méthanol ou par le glycérol, pour une consigne de production fixée à 100 kg/h. Pour parvenir à cet objectif, une revue de la littérature a permis de dégager une liste de technologies de réacteurs adaptés à ces réactions. L’analyse comparative de ces systèmes a conduit à sélectionner trois types de réacteurs intensifiés existant dans le commerce et qui ont été ensuite testés expérimentalement: les réacteurs microstructurés (type Corning®), les réacteurs micro-ondes et les réacteurs pulsés à chicanes (type NiTech®). De bonnes conversions sont obtenues pour les réactions de transestérification et d’estérification par le méthanol, montrant une meilleure efficacité de ces réacteurs intensifiés par rapport aux réacteurs conventionnels; en revanche les résultats sont encore insuffisants pour l’estérification avec le glycérol en raison de limitations en température. Concernant le réacteur micro-ondes, les excellents résultats rapportés dans la littérature sont à modérer en raison d’une imprécision de mesure de la température. La technologie de réacteurs pulsés à chicanes a finalement été retenue : leur flexibilité, l’indépendance entre le débit et le mélange généré, et enfin leur diamètre suffisamment étendu pour ne pas générer de blocage éventuel dû à l’encrassement du réacteur par la matière entrante sont les principaux arguments qui ont guidé ce choix. Le système disponible construit en verre a tout de même montré ses limites en montée en température et en pression et il a donc été envisagé d’étoffer nos investigations dans des gammes de fonctionnement plus larges. Ainsi une collaboration avec le laboratoire TNO de Delft, aux Pays-Bas a permis d’avoir accès à un réacteur pulsé à chicanes en acier inoxydable. Les résultats obtenus pour la réaction d’estérification par le glycérol - qui n’offrait pas jusqu’à présent des données concluantes - sont satisfaisants, et même de qualité supérieure comparés à ceux obtenus avec un réacteur tubulaire hélicoïdal lui aussi pulsé. Parallèlement à ces études, des simulations numériques des écoulements dans le réacteur ont permis de proposer des améliorations de la forme des chicanes, celle-ci étant déterminante pour la bonne capacité de dispersion liquide-liquide des réactifs immiscibles et la qualité du mélange. Ces simulations ont été comparées à des mesures de vitesses obtenues sur un pilote expérimental conçu pour permettre la visualisation par technique laser des écoulements dans un élément du réacteur à chicanes. Pour terminer, l’extrapolation des résultats obtenus sur les pilotes étudiés à une échelle de production de 100 kg/h a été initiée, aboutissant à la proposition d’un procédé permettant la production sélective de monoglycérides via l’estérification par le glycérol, mais également la fabrication de biodiesel par la transestérification, incluant un réacteur intensifié pulsé dont la géométrie de chicanes a été optimisée, et ce afin de répondre à l’objectif initial de la thèse. / The objective of this thesis is to propose a continuous and intensified reactor to transform waste cooking oil into products that will be used in applications in the building and public works sector. This work is part of the FUI AGRIBTP, a collaborative research project whose finality is to the creation of an industrial tool for the reuse of co-products from agroindustries. The reactor must be able to handle transesterification and esterification (with methanol or with glycerol) reactions efficiently with a total flow rate of 100 kg/h. To achieve this objective, a literature review has identified a list of suitable reactor technologies for these reactions. The comparative analysis of these different technologies has led to the selection of three types of intensified reactors microstructured reactors (Corning® type), microwave reactors and oscillatory baffled reactors (NiTech® type). The performance of these reactors for transesterification and esterification reactions has then been investigated experimentally. High conversions have been obtained for transesterification and esterification with methanol reactions, thereby showing the improved performance of these intensified reactors compared with conventional reactors; however results obtained with esterification with glycerol reaction are still rather low due to limitations in operating temperature. Concerning the microwave reactor, the excellent results previously reported in the literature should be taken with care because of the inaccuracy of temperature measurements, as proven in this work. The oscillatory baffled reactor technology has been selected has the most industrially viable equipment for the considered reactions. The flexibility of this reactor, the independency of the flow rate and mixing, as well as the diameter ,which is large enough to avoid fouling caused by the quality of the feed line, are the main reasons for this choice. The commercial available system, built in glass, has nevertheless shown limitations in terms of operating temperature and pressure. As a result, further work has focused on reactor operation in a wider range of operating conditions. To do this, a collaboration with the TNO laboratory in Delft, Netherlands, was set up in order to investigate reaction performance an oscillatory baffled reactor made of stainless steel. The reaction performance obtained for esterification with glycerol is more than satisfactory, being significantly greater that that obtained in the glass Nitech reactor and even of higher quality compared to that obtained with a oscillatory helicoidal tubular reactor. In parallel to these studies, CFD simulations of flow in the reactor have enable the investigation of new baffle designs, which play a major role in the capacity to generation liquid-liquid dispersions of the immiscible reactants and in the quality of the mixing. These simulations have been compared with velocity measurements and flow patterns obtained in a transparent experimental rig using Particle Image Velocimetry. Finally, the results obtained on the pilot-scale rigs have been used to size a the oscillatory flow reactor for a total flow rate of 100 kg/h, which would be dedicated to the selective production of monoglycerides by esterification with glycerol reaction and also biodiesel production by transesterification reaction.
6

Desenvolvimento de Usina de ProduÃÃo de Biodiesel a Partir de Ãleo de Fritura usando Simuladores de Processo: Aspectos Operacionais e Ambientais / Development of Plant Production of Biodiesel From Frying Oil Using Process Simulators: Operational and Environmental Aspects

Felipe de Oliveira Brito 30 April 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O Ãleo de fritura à um resÃduo amplamente produzido em todo o mundo. No entanto, somente alguns paÃses mais desenvolvidos possuem polÃticas de descarte ambiental correto desse resÃduo, o que o torna um poluente em potencial em naÃÃes menos esclarecidas em relaÃÃo à questÃo ambiental. Portanto, este trabalho tem como objetivo principal apresentar uma tecnologia de produÃÃo de biodiesel a partir de Ãleo de fritura como forma de aproveitamento energÃtico, aliado a uma forma ambientalmente correta de destinaÃÃo final para esse resÃduo. O trabalho se inicia com uma revisÃo bibliogrÃfica bÃsica do estado da arte da produÃÃo de biodiesel. Em seguida, apresenta-se a proposiÃÃo de um processo quÃmico para a produÃÃo de biodiesel a partir de Ãleo de fritura e por fim, tem-se uma discussÃo da tecnologia, na forma como ela foi inserida no ambiente computacional utilizado para sua elaboraÃÃo. AlÃm da apresentaÃÃo da tecnologia propriamente dita, uma avaliaÃÃo ambiental do processo à feita para mensurar a capacidade do processo de produÃÃo de biodiesel proposto de diminuir o impacto causado pelo Ãleo de fritura no ambiente. / Waste cooking oil is a residue widely produced around the world. However, only a few developed countries have policies of environmental correct disposal of this waste, which makes it a potential pollutant in less enlightened nations about the environmental issues. Therefore, this work aims to present a technology for producing biodiesel from waste cooking oil as a form of energy recovery, combined with an environmentally correct disposal for this waste. The work begins with a basic review of the state of the art in biodiesel production. Then, it presents a proposition of a chemical process to produce biodiesel from waste cooking oil and finally has a discussion of the technology the way it was inserted in the computing environment used for its elaboration. Besides the presentation of the technology itself, an environmental assessment of the process is performed to measure the ability of the proposed biodiesel production process to reduce the impact caused by the waste cooking oil in the environment.
7

Biodiesel Production by Transesterification of Waste Cooking Oil Using Modified Attapulgite.

Mabungela, Ntandokazi 10 1900 (has links)
M. Tech. (Department of Chemistry, Faculty of Applied And Computer Sciences), Vaal University of Technology. / Biodiesel has an ability to solve the problem associated with the use of fossil fuels as a source of energy. The aim of this study was to produce biodiesel from waste cooking oil (WCO) by transesterification, catalysed with potassium hydroxide (KOH) supported on attapulgite (ATP) clay as the heterogeneous catalyst. WCO was used on the basis that it is one of the cheapest feedstocks for biodiesel production, is readily available and can minimise environmental impact. ATP clay was first crushed and sieved to particle sizes of ≤ 90 μm and subsequently treated with hydrochloric acid (HCl) to remove impurities. The KOH supported ATP catalyst was prepared through ion exchange method by soaking ATP into KOH solution, dried in an oven and later calcined at 400 ℃ in a furnace. The prepared catalyst and ATP clay were characterised using Hammett indicator to determine the basic strength of the catalyst. XRF and EDX were used to determine the elemental composition of the catalyst whilst XRD was used to determine the crystallinity of the ATP after modification. The functional groups of ATP were determined by FTIR. BET was utilised to determine the changes on the surface area, pore volume and pore diameter of ATP and on the other hand, SEM was used to determine the morphological changes on the surface of ATP. The XRD, FTIR, BET AND SEM-EDX showed that addition of potassium caused changes on the surface of the ATP. The optimal conditions for the transesterification reaction of waste cooking oil with methanol were found to be oil-to-methanol molar ratio of 1:15, 3wt% catalyst amount, 65 ℃, 3 h of a reaction time, at 200 rpm stirring rate and 94 % biodiesel yield was obtained. After the catalyst was reuse three consecutive times, the decrease in biodiesel yield was observed (Figure 17) after each cycle. However, the 5MKOH/ATP catalyst is heterogeneous and can be used to transesterify WCO with good yield.
8

Production of renewable biofuels and chemicals by processing bio-feedstock in conventional petroleum refineries / Nghiên cứu khả năng tích hợp chế biến nguyên liệu sinh khối trong nhà máy lọc dầu để sản xuất nhiên liệu sinh học và hóa phẩm cho hóa dầu

Vu, Xuan Hoan, Nguyen, Sura, Dang, Thanh Tung, Armbruster, Udo, Martin, Andreas 09 December 2015 (has links) (PDF)
The influence of catalyst characteristics, i.e., acidity and porosity on the product distribution in the cracking of triglyceride-rich biomass under fluid catalytic cracking (FCC) conditions is reported. It has found that the degradation degree of triglyceride molecules is strongly dependent on the catalysts’ acidity. The higher density of acid sites enhances the conversion of triglycerides to lighter products such as gaseous products and gasoline-range hydrocarbons. The formation of gasolinerange aromatics and light olefins (propene and ethene) is favored in the medium pore channel of H-ZSM-5. On the other hand, heavier olefins such as gasoline-range and C4 olefins are formed preferentially in the large pore structure of zeolite Y based FCC catalyst (Midas-BSR). With both catalysts, triglyceride molecules are mainly converted to a mixture of hydrocarbons, which can be used as liquid fuels and platform chemicals. Hence, the utilization of the existing FCC units in conventional petroleum refineries for processing of triglyceride based feedstock, in particular waste cooking oil may open the way for production of renewable liquid fuels and chemicals in the near future. / Bài báo trình bày kết quả nghiên cứu khả năng tích hợp sản xuất nhiên liệu sinh học và hóa phẩm từ nguồn nguyên liệu tái tạo sinh khối giầu triglyceride bằng công nghệ cracking xúc tác tấng sôi (FCC) trong nhà máy lọc dầu. Kết quả nghiên cứu cho thấy xúc tác có ảnh hưởng mạnh đến hiệu quả chuyển hóa triglyceride thành hydrocarbon. Tính acid của xúc tác càng mạnh thì độ chuyển hóa càng cao và thu được nhiều sản phẩm nhẹ hơn như xăng và các olefin nhẹ. Xúc tác vi mao quản trung bình như H-ZSM-5 có độ chọn lọc cao với hợp chất vòng thơm thuộc phân đoạn xăng và olefin nhẹ như propylen và ethylen. Với kích thước vi mao quản lớn, xúc tác công nghiệp FCC dựa trên zeolite Y ưu tiên hình thành C4 olefins và các olefin trong phân đoạn xăng. Ở điều kiện phản ứng của quá trình FCC, triglyceride chuyển hóa hiệu quả thành hydrocarbon mà có thể sử dụng làm xăng sinh học cho động cơ và olefin nhẹ làm nguyên liệu cho tổng hợp hóa dầu.
9

Uso do nariz eletrônico (e-nose) como instrumento de pré-classificação de óleos e gorduras residuais (OGR) destinados à produção de biodiesel / Use of the electronic nose (e-nose) as an instrument for pre-classification of waste cooking oil (WCO) destined to biodiesel production

Batista, Pollyanna Souza 22 June 2018 (has links)
Atualmente, o uso de óleo e gordura residual (OGR) de fritura de alimentos como matéria-prima na produção de biodiesel no Brasil representa menos de 1% do total. O principal limitante é que após o processo de fritura o óleo pode adquirir características que o tornam inadequado para obtenção de biocombustível pela via de produção tradicional. Para viabilizar economicamente o reaproveitamento de OGR, é importante o desenvolvimento de métodos simples e de baixo custo capazes de avaliar seu potencial de uso como matéria prima. Nesse contexto, este trabalho teve como objetivo avaliar o uso do nariz eletrônico na seleção de OGR destinado à produção de biodiesel, em substituição aos métodos convencionais de análises físico-químicas. Foram selecionadas 36 amostras de OGR provenientes de uso doméstico e comercial, cujas características físico-químicas foram obtidas pela análise do índice de acidez, índice de peróxido, densidade e viscosidade cinemática. Biodiesel foi produzido a partir do OGR, por meio da transesterificação alcalina na temperatura de 60°C e tempo de 2h, utilizando etanol na razão molar OGR/álcool de 1/9 e hidróxido de potássio (KOH) como catalisador na quantidade de 1% m/m. As amostras de biodiesel foram caracterizadas de acordo com especificações da pela Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP), em relação ao teor de éster, índice de acidez, densidade e viscosidade cinemática. As amostras de OGR foram caracterizadas em termos do seu perfil olfativo, através do nariz eletrônico, interpretados por aplicação do modelo estocástico e análise discriminante quadrática. O modelo permitiu uma avaliação qualitativa de parâmetros de interesse sem a necessidade de testes físicoquímicos, com precisão de 80% a 92%. Os resultados demonstraram que o nariz eletrônico é uma ferramenta promissora na predição da qualidade do biodiesel com base no perfil olfativo de uma amostra de OGR. / Currently, the use of waste cooking oil (WCO) as raw material in the production of biodiesel in Brazil represents less than 1% of the total. The main limitation is that after the frying process the oil can acquire characteristics that make it unsuitable for obtaining biofuel through the traditional way of production. In order to economically make feasible the reuse of OGR, it is important to develop simple and low cost methods capable of evaluating its potential use as raw material. In this context, this work aimed to evaluate the use of electronic nose in the selection of WCO for biodiesel production, replacing the conventional methods of physical-chemical analysis. 36 samples of WCO from domestic and commercial use were selected, whose physicochemical characteristics were obtained by the analysis of acidity level, peroxide level, density and kinematic viscosity. Biodiesel was produced from the OGR by means of the alkaline transesterification at 60°C and time of 2h using ethanol in the molar ratio OGR / alcohol of 1/9 and potassium hydroxide (KOH) as catalyst in the amount of 1% m/m. The biodiesel samples were characterized according to specifications of the National Agency of Petroleum, Natural Gas and Biofuels (ANP), in relation to the ester content, acidity level, density and kinematic viscosity. The WCO samples were characterized in terms of their olfactory profile through the electronic nose, interpreted by the stochastic model and quadratic discriminant analysis. The model allowed a qualitative evaluation of parameters of interest without the need of physicalchemical tests, with precision of 80% to 92%. The results demonstrate that e-nose is a promising tool in the prediction of biodiesel quality based on the olfactory profile of a sample of WCO.
10

Biodiesel production from waste cooking oil using ionic liquid choline hydroxide as a catalyst / ProduÃÃo de biodiesel a partir de Ãleo residual de fritura utilizando o lÃquido iÃnico hidrÃxido de colina como catalisador

Aline Mara Maia Bessa 25 February 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / The production of biodiesel is generally performed by alkaline transesterification oils with low amounts of free fatty acids (FFAs). In order to decrease the costs of production of biodiesel, low quality waste cooking oils or grease have been investigated as a source alternative, but problems in the purification step due to the formation of soap are found in catalysis with sodium hydroxide. In this work, the ionic liquid choline hydroxide was produced and used as catalyst in the production of biodiesel from oils of frying food. An experimental design was carried out to investigate the influence of variables: molar ratio oil/alcohol, temperature and concentration of catalyst in the conversion of triglycerides and free fatty acids to methyl esters. The concentration of catalyst showed higher influence on conversion, followed by the molar ratio of oil / alcohol. The temperature range did not result in significant conversion changes. The kinetic analysis showed that the highest conversions were obtained with 3 hours of reaction. The statistical design allowed find optimal conditions: 5.5% w/w catalyst molar ratio of oil/methanol 1:12, temperature 40 ÂC and 3 hours of reaction. Thermodynamic properties and acid numbers were determined for reaction products of the reactions carried out in experimental design, in order to provide data for process control. The acid numbers of products of all reactions were significantly reduced, independent of conversion. To evaluate the possibility of recovery and reuse of the ionic liquid, the liquid-liquid equilibrium of systems containing water, 1-butanol and glycerin, water, 1-butanol and choline hydroxide, and the partition in the ionic liquid system water, 1-butanol and glycerin at 30  C were studied. The solubility of the components was evaluated by construction of the binodal curve and the compositions of the equilibrium phases were determined by densitometry. The results show that glycerin is distributed preferably in the phase rich in water and it was not possible to quantify all compositions the water phase system, 1-butanol and choline hydroxide in the case that an electrolytic system. / A produÃÃo de biodiesel à geralmente realizada por transesterificaÃÃo alcalina de Ãleos com baixa quantidade de Ãcidos graxos livres (AGLs). Visando diminuir os custos de produÃÃo do biodiesel, Ãleos de baixa qualidade ou residuais tÃm sido investigados como alternativa de fonte graxa, porÃm problemas na etapa de purificaÃÃo em decorrÃncia da formaÃÃo de sabÃes sÃo encontrados na catÃlise com hidrÃxido de sÃdio. Nesse trabalho, o lÃquido iÃnico hidrÃxido de colina foi produzido e aplicado como catalisador na produÃÃo de biodiesel a partir de Ãleos provenientes da fritura de alimentos. Um planejamento experimental foi realizado para investigar a influÃncia das variÃveis: razÃo molar Ãleo/Ãlcool, temperatura e concentraÃÃo de catalisador na conversÃo de triglicerÃdeos e AGLs a Ãsteres metÃlicos. A concentraÃÃo de catalisador apresentou maior influÃncia na conversÃo, seguido pela razÃo molar Ãleo/Ãlcool. A variaÃÃo de temperatura nÃo implicou em alteraÃÃes considerÃveis de conversÃo. A avaliaÃÃo cinÃtica mostrou que as maiores conversÃes foram obtidas com 3 horas de reaÃÃo. O planejamento estatÃstico permitiu encontrar condiÃÃes Ãtimas: 5,5 % m/m de catalisador, razÃo molar Ãleo/metanol de 1/12, temperatura de 40 ÂC e 3 horas de reaÃÃo. Propriedades termodinÃmicas e Ãndices de acidez foram determinados para os produtos reacionais das reaÃÃes realizadas no planejamento experimental, com o intuito de fornecer dados para o controle do processo. Os Ãndices de acidez dos produtos de todas as reaÃÃes apresentaram reduÃÃo significativa, independente da conversÃo. Para avaliar a possibilidade de recuperaÃÃo e reutilizaÃÃo do lÃquido iÃnico, o equilÃbrio lÃquido-lÃquido dos sistemas contendo Ãgua, n-butanol e glicerina, Ãgua, n-butanol e hidrÃxido de colina e a partiÃÃo do lÃquido iÃnico no sistema Ãgua, n-butanol e glicerina a 30 ÂC foram estudados. A solubilidade dos componentes foi avaliada por meio da construÃÃo da curva binodal e as composiÃÃes das fases em equilÃbrio foram determinadas atravÃs da densimetria. Os resultados mostram que a glicerina se distribui preferencialmente na fase rica em Ãgua e que nÃo foi possÃvel quantificar todas as composiÃÃes das fases do sistema Ãgua, n-butanol e hidrÃxido de colina por se tratar este de um sistema eletrolÃtico.

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