?rea de concentra??o: Produtos e coprodutos. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-06-22T19:43:47Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) barbara_goncalves_rocha.pdf: 2671242 bytes, checksum: 17dfa18bc6c5622c294695227a582c58 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-07-18T12:29:56Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) barbara_goncalves_rocha.pdf: 2671242 bytes, checksum: 17dfa18bc6c5622c294695227a582c58 (MD5) / Made available in DSpace on 2018-07-18T12:29:56Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) barbara_goncalves_rocha.pdf: 2671242 bytes, checksum: 17dfa18bc6c5622c294695227a582c58 (MD5) Previous issue date: 2018 / A diversifica??o da matriz energ?tica, por raz?es econ?micas, ambientais e da pr?pria pol?tica energ?tica das na??es, tem suscitado foco especial nos biocombust?veis, particularmente no bioetanol e no biodiesel. Na ind?stria, o biodiesel (?steres de ?cidos graxos com um ?lcool de cadeia molecular curta) ?, mais comumente, produzido pela transesterifica??o de triacilglicer?is de ?leos vegetais ou gordura animal, com metanol ou etanol, sob cat?lise homog?nea com uma base (KOH ou NaOH). Por representarem alternativas potencialmente mais sustent?veis, dos pontos de vistas econ?micos e ambientais, o presente trabalho foi dedicado a avaliar a efici?ncia qu?mica de catalisadores heterog?neos baseados em materiais de min?rios: (i) de ni?bio, enriquecido em Nb2O5 (Geo.Nb2O5); (ii) de areia monaz?tica (Geo.Mona), uma fonte mineral de terras raras, e (iii) de rejeitos de minera??o de fosfato, ricos em magnetita (Geo.Mag.CMT e Geo.Mag.CMA). Os materiais minerais foram preparados em mistura com componentes ?cidos (H2SO4; HCl ou HF) ou b?sicos (KOH; , KBr, NaOH; CaO; KI; KF ou KCl). As rea??es de transesterifica??o foram conduzidas sob refluxo, com ?leo de soja comercial e metanol, sob a??o dos catalisadores s?lidos. A raz?o molar padr?o ?leo:metanol foi de 1:100, com 10% de catalisador em rela??o ao ?leo, a 60 ?C. Dos testes realizados com os materiais preparados com CaO sint?tico comercial, nas mesmas condi??es, a mistura calcinada a 800 ?C por 4 h rendeu ?steres met?licos sempre acima de 99%; o menor tempo de rea??o (2 h, para completar a transesterifica??o) foi conseguido com o catalisador baseado na Geo.Mona, em rela??o ao Geo.Nb2O5 (5 h), ao Geo.Mag.CMT (3 h) e o Geo.Mag.CMA tamb?m (2 h). Analisou-se o reuso consecutivo do catalisador. Ap?s cada rea??o, o catalisador s?lido era lavado com metanol e seco a 100 oC. O melhor resultado foi obtido com o rejeito magn?tico com CaO calcinados a 200 ?C por 4 h, para o que se conseguiu at? 8 rea??es consecutivas. Nas impregna??es com ?cidos e bases, os melhores resultados foram com a mistura Geo.Nb2O5 e KOH calcinada a 600 ?C, para a qual conseguiu 8 rea??es consecutivas, com rendimento qu?mico em ?steres met?licos de praticamente 100% e tempo reacional de 10 min, no primeiro uso. O efeito catal?tico sin?rgico mais significativo foi conseguido com o catalisador baseado em cada um dos tr?s materiais avaliados em mistura com CaO: nenhum efeito catal?tico significativo na rea??o de transesterifica??o de triacilglcier?is do ?leo foi observado apenas com o material mineral puro calcinado. O CaO puro como catalisador, tamb?m calcinado e usado em rea??o, levou a rendimentos qu?micos pouco acima de 80%. A mistura individual do material mineral com CaO, nas mesmas condi??es de prepara??o anteriores, levaram a rendimentos qu?micos de efetivamente 100%. Os presentes resultados revelam a excepcional potencialidade, dos pontos de vista qu?mico, econ?mico e ambiental, dos catalisadores mistos, dos materiais minerais com CaO, ora avaliados, nos processos de produ??o industrial de biodiesel. / Tese (Doutorado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The diversification of the energy matrix has been drawing special attention to biofuels, especially bioethanol and biodiesel, mainly for economic and environmental reasons and national energy policies. In industry, biodiesel (esters of fatty acids with a short-chain alcohols) is most commonly produced by the transesterification of triacylglycerols in vegetable oils or animal fats with methanol or ethanol using homogeneous catalysis with a base (KOH or NaOH). The present work was devoted to the evaluation of the chemical efficiency of heterogeneous catalysts based on mineral materials: (i) niobium, enriched in Nb2O5 (Geo.Nb2O5); (ii) monazite sand (Geo.Mona), a mineral source of rare earths, and (iii) phosphate mining tailings, rich in magnetite (Geo.Mag.CMT e Geo.Mag.CMA). The mineral materials were prepared in admixture with acidic (H2SO4, HCl or HF) or basic (KOH, KBr, NaOH, CaO, KI, KF or KCl) components. The transesterification reactions were conducted under reflux with commercial soybean oil and methanol in the presence of the solid catalysts. The standard molar ratio of oil:methanol was 1:100, using 10% catalyst relatively to the quantity of oil, at 60 ?C. According to the tests performed with the materials prepared with commercial synthetic CaO under the same conditions, the yield of methyl esters with the mixture calcined at 800 ?C for 4 h was always greater than 99%. The shortest reaction time (2 h to complete the transesterification) was achieved with the Geo.Mona catalyst; the reaction times with Geo.Nb2O5 (5 h), the Geo.Mag.CMT (3 h) and the Geo.Mag.CMA also (2 h) were longer. The consecutive reuse of the catalyst was also verified. After each reaction, the solid catalyst was washed with methanol and dried at 100 ?C. The best result was obtained with the magnetic waste with CaO calcined at 200 ?C for 4 h, with which up to eight consecutive reactions were achieved. On impregnating with acids or bases, the best results are obtained with the Geo.Nb2O5 and KOH mixture calcined at 600 ?C, with which eight consecutive reactions were completed. Virtually 100% yields of methyl esters were obtained in a reaction time of 10 min in the first use. The most significant synergistic catalytic effect was achieved with each of the three minerals mixed with CaO. No significant catalytic effect on the transesterification reaction of triacylglycerols in the oil was observed with the pure calcined minerals. When the calcined CaO is used alone as catalyst, the reaction yielded just over 80%. For the mixture of the individual minerals with CaO under the same preparation conditions described above, the transesterification reaction led to virtually 100% yields. The present results reveal an outstanding potential regarding the chemical, economic and environmental aspects of the mixed catalysts (the mineral material with CaO) for chemical processes leading to the industrial production of biodiesel.

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-11-05T21:41:01Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-11-10T11:58:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) / Made available in DSpace on 2018-11-10T11:58:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) Previous issue date: 2018 / O catalisador denominado SiO2-SO3H foi empregado em tr?s processos reacionais distintos: transesterifica??o, cetaliza??o e eterifica??o. Utilizado em uma propor??o de 20% (m/m) contendo tolueno, o SiO2-SO3H se mostrou muito eficiente no processo de transesterifica??o de triacilglicer?deos fornecendo glicerol e ?steres met?licos de ?cidos graxos (biodiesel) com um rendimento de 98%. Empregou-se o glicerol obtido como reagente em uma mistura com acetona, em um meio reacional livre de solventes e utilizando o SiO2-SO3H, obteve-se convers?o total e 100% de seletividade para o composto contendo o anel de 5 membros [(?)- 2,2-Dimetil-4-hidroximetil-1,3-dioxolano] conhecido como solketal, um produto qu?mico vers?til, com diversas aplica??es, na ind?stria de cosm?tico e farmac?utica, al?m de aditivo para diesel com a finalidade de reduzir o ponto de congelamento, melhorar as propriedades lubrificantes e aumentar a pot?ncia anti-detonante. Posteriormente realizou-se o processo de eterifica??o do solketal, empregando o catalisador SiO2-SO3H, levando a forma??o do 4,4'-[oxibis(metileno)]-bis(2,2-dimetil-1,3-dioxolano)], ??ter de di-solketal?, precursor do diglicerol, importante emulsificante das ind?strias farmac?utica e aliment?cia com 98% de rendimento. A eterifica??o do solketal foi tamb?m promovida empregando o catalisador denominado SiO2-Nb levando a forma??o do 4,4'-[oxibis(metileno)]-bis(2,2-dimetil-1,3-dioxolano)], ??ter de di-solketal? com um rendimento de 96%. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / The catalyst called SiO2-SO3H was at the forefront of several distinct reaction processes: transesterification, ketalization and etherification. Used at a ratio of 20% (m / m) to toluene, SiO2 -SO3H became very efficient in the transesterification process of triacylglycerides, providing glycerol and fatty acid methyl esters (biodiesel) in 98% yield. The glycerol was used as reagent in a mixture with acetone, in a solvent-free reaction medium and in the use of SiO2 -SO3H, obtained and 100% total resolution for the compound with the 5-membered compound [(?) - 2,2-Dimethyl-4-hydroxymethyl-1,3-dioxolane], known as solalto, a versatile chemical with various applications in the cosmetic and pharmaceutical industry, as well as a diesel additive for freezing purpose, lubricants and increase anti-detonating power. Subsequently, the sputtering determination was carried out using the SiO2 -SO3H catalyst, leading to the formation of 4,4 '- [oxybis (methylene)] bis (2,2-dimethyl-1,3-dioxolane)], di-solketal, precursor of diglycerol, a major emulsifier of the pharmaceutical and food industries in 98% yield. The etherification of the solketal was also promoted using the catalyst called SiO2-Nb leading to the formation of 4,4 '- [oxybis (methylene)] bis (2,2-dimethyl-1,3-dioxolane)], di -solketal "in 96% yield.

Submitted by Natalie Mendes (nataliermendes@gmail.com) on 2015-07-25T15:50:08Z No. of bitstreams: 1 Tese Maiara.pdf: 2672391 bytes, checksum: dc66f1334066cfacd2ccc16772a88c08 (MD5) / Made available in DSpace on 2015-07-25T15:50:08Z (GMT). No. of bitstreams: 1 Tese Maiara.pdf: 2672391 bytes, checksum: dc66f1334066cfacd2ccc16772a88c08 (MD5) Previous issue date: 2014-02-18 / Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB / The biodiesel is an alternative to petrochemicals and derivatives because it is produced from renewable sources, as vegetable oils and animal fat, and reduces the level of pollutant emissions in the diesel. The investigation of alternative sources of triglycerides for biodiesel production has been extensively explored. In this work, seeds of 26 of different plant species (Leguminosae, Myrtaceae, Celastraceae, Chrysobalanaceae, Rubiaceae, Rutaceae, Sapindaceae) of the semiarid region of the State of Bahia were collected and the oil extracted for studies as alternative source for the production of biodiesel. The present work selected the most promising plant species for the production of biodiesel, using the chromatography methods CG-MS and CG-FID to identify the fatty acids in the oils, followed by the physical-chemical characterization of the oils from the most promiing species: Syagrus coronata, Dilodendron bipinnatum, (mamoninha) and Magonia pubescens (timb?). Thus, acid index, saponification index, peroxide value, iodine index, and refractive index were determined. Because presents better physical-chemical characteristics, the oil of ?Timb?? was selected for the experiment about the best process conditions to produce ?Timb?? biodiesel in order to improve methyl esters production (% m/m). ?Timb?? biodiesel was produced by methanol route using alcohol/oil molar ratio 8:1, the concentration of catalyst was 0,5 wt%. The values determined for the physical-chemical parameters of the Timb? Methyl Biodiesel (BMT) are within the limits established by the National Agency for Petroleum, Natural Gas and Biofuels ? ANP, except for acid index, total glycerin and kinematic viscosity. / O biodiesel ? uma alternativa em rela??o ao petr?leo e seus derivados j? que ? obtido de fontes renov?veis, como ?leos vegetais e gorduras animais e reduz a emiss?o de compostos poluentes presentes no diesel. A investiga??o de fontes alternativas de triglicer?deos para a produ??o de biodiesel tem sido bastante explorada. Neste sentido, sementes de 26 esp?cies de plantas (Leguminosae, Myrtaceae, Celastraceae, Chrysobalanaceae, Rubiaceae, Rutaceae, Sapindaceae) encontradas na regi?o semi?rida da Bahia foram coletadas e o ?leo extra?do para estudar quanto a sua viabilidade para uso em biodiesel. Foram selecionadas as esp?cies vegetais mais promissoras para a produ??o de biodiesel, utilizando os m?todos cromatogr?ficos CG-MS e CG-FID como ferramentas para identificar os ?cidos graxos presentes nos ?leos, seguido pela caracteriza??o f?sico-qu?mica dos ?leos das esp?cies consideradas mais promissoras Syagrus coronata, Dilodendron bipinnatum, a mamoninha e Magonia pubescens, o timb?, determinando ?ndice de acidez, ?ndice de saponifica??o, ?ndice de per?xido, ?ndice de iodo e ?ndice de refra??o. Por apresentar boas caracter?sticas f?sico-qu?micas, o ?leo de ?timb?? foi selecionado para a realiza??o de experimento sobre as melhores condi??es operacionais para produzir biodiesel, visando melhorar o rendimento de ?steres (%m/m). O biodiesel de timb? foi obtido por rota met?lica, utilizando rela??o molar ?lcool:?leo 8:1 e a concentra??o do catalisador foi de 0,5% em rela??o ? massa de ?leo. Os valores determinados para os par?metros f?sico-qu?micos do biodiesel met?lico de timb? (BMT) encontram-se dentro dos limites estabelecidos pela Ag?ncia Nacional de Petr?leo, G?s Natural e Biocombust?vel (ANP), por?m o processo de transesterifica??o necessita de alguns ajustes para melhorar o ?ndice de acidez, glicerina total e viscosidade cinem?tica.

Made available in DSpace on 2014-12-17T14:52:48Z (GMT). No. of bitstreams: 1 JaneteMBP_DISSERT.pdf: 1475621 bytes, checksum: 1fbc2d7ccc4198e247c3fcdf44c5a178 (MD5) Previous issue date: 2009-11-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work addresses biodiesel by transesterification from the use of waste frying oil as a possible technological alternative for both reducing greenhouse gas emissions and by presenting themselves as an environmental call to designate a rational use of oil when no longer played in the environment to become renewable energy. It has proposed location of a residual oil and fat treatment plant to produce biodiesel, using models of Location and Routing for the improvement of routes. To achieve the goal, questionnaires were administered in establishments that use oil or vegetable fat in their productive activities in order to quantify the residue, to analyze actions and environmental perception of people who work directly with the residue on the destination you are being given to oil and fat used. It has indicated using of two single setup location, the method of Center of Gravity and the model of Ardalan, a geographical point that minimizes the costs of transporting waste to the treatment plant. Actions have been proposed for the improvement of collection routes this residue using the Routing Method of Scanning, as an illustration. The results demonstrated the lack of knowledge of the people who deal directly with large amounts of waste, on the environmental impacts caused by their incorrect disposal. The models used were uniform since point out to neighborhoods in similar regions. The neighborhoods of Lagoa Nova / Morro Branco (Ardalan) and Nova Descoberta (Center of Gravity) as ideal for the installation of treatment plant. However, it is suggested to be tested other models that take into account new variables than those used (supply of waste and the distance between points). The routing through the method of scanning has shown that it is possible, in a simple way to optimize routes in order to reduce distances and therefore the logistics costs in the collection of such waste. Introducing a route as a test to gather the twenty largest oil suppliers used in sample frying, using as a main factor time 8 hour of working shift every day / O trabalho aponta o biodiesel por transesterifica??o a partir do aproveitamento de ?leos residuais de fritura como uma das poss?veis alternativas tecnol?gicas tanto para redu??o das emiss?es de gases, quanto por apresentar-se como um apelo ambiental ao designar um uso racional deste ?leo quando deixado de ser jogado no meio ambiente para tornar-se energia renov?vel. Prop?e a localiza??o de uma unidade de tratamento de ?leo e gordura residual para produ??o de biodiesel, usando modelos de Localiza??o e Roteiriza??o para aperfei?oamento das rotas. Para alcan?ar o objetivo foram aplicados question?rios em estabelecimentos que utilizam o ?leo e/ou a gordura vegetal em suas atividades produtivas, no intuito de quantificar o res?duo; analisar as a??es e a percep??o ambiental das pessoas que trabalham diretamente com o res?duo sobre o destino que est? sendo dado ao ?leo e a gordura usados. Indica atrav?s de duas t?cnicas de instala??o ?nica de localiza??o, o m?todo do Centro de Gravidade e o modelo de Ardalan, um ponto geogr?fico que minimize os custos de transporte do res?duo at? a unidade de tratamento. Prop?e a??es para o aperfei?oamento das rotas de coleta deste res?duo utilizando o M?todo de Roteiriza??o da Varredura, a t?tulo de ilustra??o. Os resultados obtidos nas empresas demonstraram falta de conhecimento das pessoas que lidam diretamente com grandes quantidades do res?duo, sobre os impactos ambientais causados por seu descarte incorreto. Os modelos de localiza??o utilizados apresentaram uniformidade visto que apontaram para bairros em regi?es similares. Os bairros de Lagoa Nova/Morro Branco (Ardalan) e Nova Descoberta (Centro de Gravidade) como ideais para a instala??o da unidade de tratamento. Por?m, sugere-se que sejam testados outros modelos que levem em considera??o novas vari?veis al?m das que foram utilizadas (oferta de res?duo e dist?ncia entre os pontos). A roteiriza??o pelo m?todo da Varredura demonstrou que ? poss?vel, de forma simples, otimizar rotas a fim de reduzir dist?ncias e consequentemente os custos log?sticos na coleta desses res?duos. Apresentando uma rota a t?tulo de ensaio para recolhimento nos vinte maiores ofertantes de ?leo usado em fritura da amostra, utilizando como fator principal o tempo de 8 horas de jornada de trabalho di?rias

Made available in DSpace on 2014-12-17T15:01:15Z (GMT). No. of bitstreams: 1 GiselleSA.pdf: 952912 bytes, checksum: 583e1e7c4f17927714ce3fb3a4b8916d (MD5) Previous issue date: 2008-09-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The production of biodiesel has become an important and attractive process for the production of alternative fuels. This work presents a study of the biodiesel production from coconut oil (Cocos nucifera L.), by two routes: direct transesterification using NaOH as catalyst and esterification (with H2SO4) followed by basic transesterification. The reactor was built in pirex with 1L of capacity and was equipped with a jacket coupled with a thermostatic bath to temperature control, a mecanical stirring is also present in the reactor. The analysis of oil composition was carried out by gas chromatography and esters compounds were identified. The parameters of molar ratio oil/alcohol, reaction time and temperature were studied and their influence on the conversion products was evaluated using experimental planning (23). The molar ratio was the most significant variable by the statistical planning analysis. Conversions up to 85.3% where achived in the esterification/transesterification, with molar ratio 1:6 at 60?C and 90 minutes of reaction. For the direct transesterification, route conversions up 87.4% eas obtained using 1:6.5 molar ratio at 80?C and 60 minutes of reaction. The Coconut oil was characterized by their physic chemical properties and key constituents of the oil. The lauric acid was the main constituint and the oil showed high acidity. The biodiesel produced was characterized by its main physicochemical properties, indicating satisfactory results when compared to standard values of National Petroleum Agency. The work was supplemented with a preliminary assessment of the reaction kinetic / A produ??o de biodiesel tem se tornado um processo atrativo visando o est?mulo na produ??o de combust?veis alternativos. Este trabalho apresenta resultados do estudo da produ??o de biodiesel a partir de ?leo de coco (Cocos nucifera L.), atrav?s de duas rotas: transesterifica??o direta utilizando o NaOH como catalisador e cat?lise ?cida (com H2SO4) seguida de transesterifica??o b?sica. O reator utilizado foi constru?do de vidro pirex de aproximadaente 1L, enjaquetado, com tr?s sa?das, onde foi introduzido um agitador mec?nico e acoplado um banho termostatizado para controle da temperatura. A determina??o da composi??o do ?leo e identifica??o dos ?steres foi feita atrav?s de cromatografia gasosa. Foi avaliado o efeito das vari?veis: raz?o molar ?leo/?lcool, tempo de rea??o e temperatura sobre a convers?o atrav?s de um planejamento experimental 23 com ponto central em triplicata para cada rota analisada. A vari?vel raz?o molar foi a que exerceu maior efeito como resultado da an?lise do planejamento estat?stico. Na rota 1 (cat?lise ?cida seguida de cat?lise b?sica) a m?xima convers?o alcan?ada foi de 85,3% para uma raz?o molar de 1:6, temperatura de 60?C e tempo de rea??o de 90 minutos. Na transesterifica??o b?sica direta, a m?xima convers?o alcan?ada foi de 87,4% para uma raz?o molar de 1:6,5, temperatura de 80?C e tempo de rea??o de 60 minutos. O ?leo de Coco foi caracterizado em rela??o as suas propriedades fisico-qu?micas e principais constituintes presentes no ?leo. O ?cido l?urico foi seu principal componente e o mesmo apresentou elevada acidez. O biodiesel produzido foi caracterizado em rela??o as suas principais propriedades f?sico-qu?micas que apresentaram resultados bastante satisfat?rios quando comparados com os valores estabelecidos pelas normas da Ag?ncia Nacional do Petr?leo. O trabalho foi complementado com uma avalia??o preliminar da cin?tica da rea??o

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-08-01T11:55:04Z No. of bitstreams: 1 CarolineSuzyDoNascimentoGarcia_DISSERT.pdf: 16990890 bytes, checksum: fc4709c79411594f09f07fcf6dd8768d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-08-02T14:05:58Z (GMT) No. of bitstreams: 1 CarolineSuzyDoNascimentoGarcia_DISSERT.pdf: 16990890 bytes, checksum: fc4709c79411594f09f07fcf6dd8768d (MD5) / Made available in DSpace on 2017-08-02T14:05:58Z (GMT). No. of bitstreams: 1 CarolineSuzyDoNascimentoGarcia_DISSERT.pdf: 16990890 bytes, checksum: fc4709c79411594f09f07fcf6dd8768d (MD5) Previous issue date: 2017-03-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Ap?s o processamento da manga nas ind?strias de polpas e sucos, toneladas de res?duos, como casca e caro?o, s?o descartados sem o devido aproveitamento. Cerca de 15% do peso da manga, a depender da sua variedade, ? devido ao caro?o, a partir do qual ? poss?vel obter o amido. A fim de agregar valor a esse res?duo, este trabalho teve como objetivo a obten??o de um ?ster do amido extra?do da manga (Tommy Atkins), atrav?s da rea??o de transesterifica??o do laurato de vinila (LV) com o amido. Tamb?m foi avaliada a utiliza??o desse amido em fluidos de perfura??o em po?os de petr?leo ? base de emuls?o inversa (A/O), devido ao alto interesse em desenvolver fluidos n?o-aquosos de baixa toxicidade e com elevado desempenho em condi??es de temperatura e press?es elevadas. A s?ntese foi realizada na presen?a de um catalisador b?sico (K2CO3), em dimetilsuf?xido (DMSO), a 110?C e atmosfera de N2(g), durante 3 ou 4 horas. Os produtos obtidos foram purificados por precipita??o em metanol e/ou ?lcool isoprop?lico e caracterizados por espectroscopia no infravermelho com transformada de Fourier (FTIR), Resson?ncia Magn?tica Nuclear de hidrog?nio (RMN 1H) e de carbono (RMN 13C), an?lise termogravim?trica (TG), testes de solubilidade e microscopia eletr?nica de varredura (MEV). O FTIR confirmou que o laurato de amido foi obtido, atrav?s do deslocamento da banda de carbonila em 1759 cm-1 do ?ster vin?lico no laurato de vinila, para 1743 cm-1, no ?ster saturado do amido modificado, essa banda de ester saturado ? ausente no amido nativo. Atrav?s do RMN 1H foi poss?vel determinar um grau de modifica??o qu?mica de 1,13. O espectro de RMN 13C do derivado de amido apresentou um pico em 173 ppm, que pode ser atribu?do a carbonila de ?ster saturado. A an?lise termogravim?trica mostrou que o amido modificado apresenta maior estabilidade t?rmica que seus precursores e que uma mistura f?sica entre amido e laurato de vinila. Os testes de solubilidade tamb?m confirmaram a modifica??o qu?mica, j? que, ao contr?rio do amido, o produto apresentou solubilidade em tolueno e clorof?rmio, e permaneceu insol?vel em ?gua e DMSO. Os dados do MEV mostraram que, ap?s a modifica??o qu?mica, os dom?nios cristalinos do amido foram desfeitos e o aspecto exibido na micrografia ? desestruturado (amorfo). Os resultados experimentais dos fluidos estudados indicaram que o produto obtido da s?ntese apresentou desempenho superior ao fluido com aditivo comercial no controle do filtrado. / After processing of mango in pulp and juices industries, tons of residues such as shell and seed are discarded without proper use. About 15% of the weight of the mango, depending on its variety, is due to the seed, from which it is possible to obtain the starch. In order to add value to this residue, this study aimed to produce an ester from mango starch (Tommy Atkins), through the transesterification reaction of vinyl laurate (LV) with starch. It was also evaluated the use of this starch in drilling fluids based on invert emulsion (W/ O), due to the high interest in developing nonaqueous fluids of low toxicity and high performance under high temperature and pressure conditions. The synthesis was performed in the presence of a basic catalyst (K2CO3) in dimethyl sulfoxide (DMSO) at 110 ? C and N2(g). The product was purified by precipitation in methanol and characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear Magnetic Resonance of hydrogen (1H NMR) and carbon (13C NMR), thermal gravimetric analysis (TGA), solubility tests and scanning electron microscopy (SEM). FTIR confirmed the starch laurate was obtained, by displacing the C=O band from the vinyl ester at 1759 cm-1, to 1743 cm-1 in vinyl laurate, due to satured ester in the modified starch, this saturated ester band is absent in the native starch. Through 1H NMR it was possible to determine a degree of chemical modification of 1.13. The13 C-NMR spectrum of the starch derivative showed a peak at 173 ppm, which can be attributed to saturated ester carbonyl. Thermogravimetric analysis showed that the modified starch has higher thermal stability than its precursors and than a physical blend of starch and vinyl laurate. Solubility tests also confirmed the chemical modification, since, unlike the starch, the product was soluble in toluene and chloroform, and remained insoluble in water and DMSO. SEM data showed that crystalline domains on starch were broken after chemical modification and the appearance shown in micrograph is unstructured (amorphous). The experimental results of the studied fluids indicate that the obtained product of the synthesis presented superior performance to the fluid with commercial additive in the control of the filtrate.

Made available in DSpace on 2014-12-17T15:41:45Z (GMT). No. of bitstreams: 1 AlineAApdf.pdf: 2403213 bytes, checksum: dfc50c5f35575298ed9005c5d3fb4f7b (MD5) Previous issue date: 2009-08-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this paper, the Layered Double Hydroxides (LDH s) type hydrotalcite were synthesized, characterized and tested as basic heterogeneous catalysts for the production of biodiesel by transesterification of sunflower oil with methanol. The synthesis of materials Layered Double Hydroxides (LDH s) by co-precipitation method from nitrates of magnesium and aluminum, and sodium carbonate. The materials were submitted to the variation in chemical composition, which is the amount of Mg2+ ions replaced by Al3+. This variation affects the characteristic physico-chemical and reaction the solid. The molar ratio varied in the range of 1:1 and 3:1 magnesium / aluminum, and their values between 0.2 and 0.33. This study aims to evaluate the influence of variation of molar ratio of mixed oxides derived from LDH s and the influence of impregnation of a material with catalytic activity, the KI, the rate of conversion of sunflower oil into methyl esters (biodiesel) through transesterification by heterogeneous catalysis. .The catalysts were calcined at 550 ? C and characterized by X-ray diffraction (XRD), scanning electron microscopy and energy dispersive spectroscopy of X-ray (SEM / EDS), thermogravimetric analysis (TG) and test basicity. The transesterification reaction was performed for reflux is a mixture of sunflower oil and methanol with a molar ratio of 15:1, a reaction time of 4h and a catalyst concentration of 2% by weight. The physical-chemical characterization of sunflower oil and biodiesel obtained by the route methyl submitted according NBR, EN, ASTM. Subsequently, it was with the chromatographic and thermogravimetric characterizations of oils. The results of chromatographic analysis showed that the catalysts were effective in converting vegetable oil into biodiesel, in particular the type hydrotalcite KI-HDL-R1, with a conversion of 99.2%, indicating the strong influence of the chemical composition of the material, in special due to presence of potassium in the structure of the catalyst / Neste trabalho, hidr?xidos duplos lamelares tipo hidrotalcita foram sintetizados, caracterizados e testados como catalisadores heterog?neos b?sicos para a produ??o de biodiesel por transesterifica??o de ?leo de girassol com metanol. A s?ntese dos materiais de hidr?xidos duplos lamelares (HDLs) procedeu-se pelo m?todo de co-precipita??o, a partir de nitratos de magn?sio e de alum?nio, carbonato de s?dio e hidr?xido de s?dio. Os materiais foram submetidos ? varia??o na propor??o qu?mica, que equivale ? quantidade de ?ons Mg2+ substitu?dos por Al3+. Essa varia??o afeta as propriedades f?sico-qu?micas do material. A raz?o molar variou na propor??o de 1:1 e 3:1 de magn?sio/alum?nio, estando seus valores entre 0,2 e 0,33. Realizou-se um estudo de impregna??o de iodeto de pot?ssio na estrutura dos HDLs, a fim de verificar se ocorre um aumento da basicidade nesses materiais. Os catalisadores obtidos foram calcinados ? 550 ?C e caracterizados por difra??o de raios X (DRX), microscopia eletr?nica de varredura e espectroscopia por energia dispersiva de raios X (MEV/EDS), an?lise termogravim?trica (TG) e teste de basicidade. A rea??o de transesterifica??o foi realizada refluxando-se uma mistura de metanol e ?leo de girassol com uma raz?o molar de 15:1, tempo de rea??o de 4h e uma concentra??o de 2% em massa de catalisador. A caracteriza??o f?sico-qu?mica do ?leo de girassol e dos biodieseis obtidos atrav?s da rota met?lica apresentou-se de acordo com as normas da NBR, EN, ASTM. Realizaram-se tamb?m as caracteriza??es cromatogr?ficas e termogravim?tricas dos biocombust?veis obtidos. Os resultados das an?lises cromatogr?ficas mostraram que os catalisadores foram eficientes na convers?o de ?leo vegetal em biodiesel, em especial o tipo hidrotalcita KI-HDL-R1, com uma convers?o de 99,2%, indicando a forte influ?ncia da composi??o qu?mica do material, particularmente com a presen?a do iodeto de pot?ssio na estrutura do catalisador

Made available in DSpace on 2014-12-17T15:41:54Z (GMT). No. of bitstreams: 1 JoaoPCE_DISSERT.pdf: 3180656 bytes, checksum: 4103bde23e39119f96e6397a04b288a2 (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This study proposes to find a biodiesel through transesterification of rice bran oil with KI/Al2O3 checking the influence of two types of alumina (Amorphous and Crystalline) for conversion into methyl esters. The catalyst was synthesized by the wet impregnation method. Adding 30 mL of 35% KI(aq.) in 10 g of alumina, under stirring at 80 ?C for 3 hours. The reaction conditions used in this study were optimized, with a molar ratio methanol:oil of 15:1, 8 h of reaction time and reflux temperature. The catalyst amount was varied in the range of 1 to 5 % wt. The solid catalysts materials were analyzed by: x-ray diffraction (XRD), thermogravimetry (TG), N2 adsorption/desorption, scanning electron microscopy (SEM) and basicity, for the identification of its structure and composition, verifying the presence of basic sites. The results showed that Al2O3(A) presents an amorphous structure, high surface area and a better catalytic activity, in relation to the catalyst synthesized with Al2O3(C) support that proved to have a more crystalline structure, having as well, a lesser surface area, enabling difficulties for the incorporation of active sites. The obtained biodiesel with 5% wt. KI/Al2O3(A) presented physicochemical properties within the standards specified by the Resolution No 7/2008 ANP and obtained the best reaction yield with 95.2%, according to quantitative measurement from the TG, which showed 96.2% conversion into methyl esters. It was furthermore found that with the increasing amount of the quantity of the catalyst in the reaction, there was also an increase in the ester content obtained. The specific mass and the kinematic viscosity were reduced with the increase of the amount of quantity of the catalyst, indicating an increase in the conversion of triglycerides / Esse estudo prop?e-se a obter um biodiesel a partir da transesterifica??o do ?leo de farelo de arroz com KI/Al2O3 verificando a influ?ncia de dois de tipos de alumina (Amorfa e Cristalina) na convers?o em ?steres met?licos. O catalisador foi sintetizado pelo m?todo de impregna??o via ?mida. Adicionando 30 mL de uma solu??o de 35% KI(aq.) em 10 g de alumina, sob agita??o constante a 80?C por 3h. As condi??es reacionais utilizadas nesse estudo foram otimizadas, como raz?o molar de metanol:?leo de 15:1, tempo reacional de 8hs e temperatura de refluxo. A quantidade de catalisador foi variada na faixa de 1 a 5% wt. Os materiais s?lidos catal?ticos foram analisados por: difra??o de raios-X (DRX), an?lise termogravim?trica (TG/DTG), adsor??o/dessor??o de nitrog?nio, microscopia eletr?nica de varredura (MEV) e teste de basicidade para identifica??o da estrutura e sua composi??o, verificando a presen?a de s?tios b?sicos. Os resultados mostraram que Al2O3(A) apresenta uma estrutura amorfa, alta ?rea superficial e uma melhor atividade catal?tica em rela??o ao catalisador sintetizado com o suporte Al2O3(C) que mostrou-se uma estrutura mais cristalina, menor ?rea superficial, dificultando a incorpora??o dos s?tios ativos. O biodiesel obtido com 5% wt. KI/Al2O3(A) apresentou propriedades f?sico-qu?micas dentro das normas especificadas pela resolu??o N?7/2008 da ANP e o melhor rendimento da rea??o com 95,2%, em conformidade com a medida quantitativa a partir da TG, que exibiu 96,2% de convers?o em ?steres met?licos. Foi verificado que com o aumento da quantidade de catalisador na rea??o, aumenta o teor de ?steres obtidos. A massa espec?fica e a viscosidade cinem?tica foram reduzidas com o aumento da quantidade de catalisador, indicando um aumento na convers?o dos triglicer?deos

Made available in DSpace on 2014-12-17T15:41:58Z (GMT). No. of bitstreams: 1 JulioCTS_DISSERT.pdf: 2360843 bytes, checksum: 9fc8ef936717b3177303c0d0bd2e0718 (MD5) Previous issue date: 2012-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / It is known that the head office world energetics is leaning in the fossil fuels. However, the world panorama is changing quickly, for linked reasons to three of the humanity's great concerns in that century beginning: environment, global economy and energy. The biodiesel production is based on the transesterifica??o of vegetable oils or animal fats, using catalysts homogeneous or heterogeneous. The process of heterogeneous transesterifica??o presents lower conversions in comparison with the homogeneous, however, it doesn't present corrosion problems and it reduces to the occurrence of parallel reactions as saponification. In this sense, this work has for purpose the synthesis of a heterogeneous catalyst, KNO3/Al2O3, that soon afterwards was used in the reaction of transesterifica??o of the oil of the Helianthus annuus L. (sunflower). The solid materials (it supports and catalyst) they were analyzed by diffraction of ray-X (XRD) and electronic microscope of sweeping (MEV). After the analysis of Al2O3, a structure monophase amorphous tetragonal was verified, with characteristic patterns of that material, what could not be visualized in the difratograma of the catalyst. The biodiesel obtained with 4% wt. of KNO3/Al2O3 it was what obtained a better cinematic viscosity 8,3 mm2/s, comparing with the norms of ANP, and it also presented the best conversion tax in ethyl ?steres, in accordance with the quantitative measure starting from TG, that was of 60%. While the biodiesel with 6% wt. and with 8% wt. of KNO3/Al2O3 it was it that no transesterificou, because it was observed in the analysis termogravim?trica of those two materials, a single thermal event, that it corresponds the decomposition or volatilization of the triglycerides / Sabe-se que a matriz energ?tica mundial est? apoiada nos combust?veis f?sseis. No entanto, o panorama mundial est? mudando rapidamente, por motivos ligados a tr?s das grandes preocupa??es da humanidade nesse in?cio de s?culo: meio ambiente, economia global e energia. A produ??o de biodiesel ? baseada na transesterifica??o de ?leos vegetais ou gorduras animais, utilizando catalisadores homog?neos ou heterog?neos. O processo de transesterifica??o heterog?nea apresenta convers?es mais baixas em compara??o com o homog?neo, por?m, n?o apresenta problemas de corros?o e reduz ? ocorr?ncia de rea??es paralelas como saponifica??o. Neste sentido, este trabalho tem por finalidade a s?ntese de um catalisador heterog?neo, o KNO3/Al2O3, que em seguida foi utilizado na rea??o de transesterifica??o do ?leo da Helianthus annuus L.(girassol). Os materiais s?lidos (suporte e catalisador) foram analisados por difra??o de raios-X (DRX) e microsc?pio eletr?nico de varredura (MEV). Ap?s a an?lise da Al2O3, foi constatada uma estrutura monof?sica tetragonal amorfa, com padr?es caracter?sticos desse material, o que pode ser visualizado no difratograma do catalisador. O biodiesel obtido com 4% m/m de KNO3/Al2O3 foi o que obteve uma melhor viscosidade cinem?tica 8,3 mm2/s, comparando com as normas da ANP, e tamb?m apresentou a melhor taxa de convers?o em ?steres et?licos, em conformidade com a medida quantitativa a partir da TG, que foi de 60%. Enquanto o biodiesel com 6% m/m e com 8% m/m de KNO3/Al2O3 foi o que n?o transesterificou, pois foi observado na an?lise termogravim?trica desses dois materiais, um ?nico evento t?rmico, que corresponde a decomposi??o ou volatiliza??o dos triglicer?deos

Made available in DSpace on 2014-12-17T15:42:16Z (GMT). No. of bitstreams: 1 LuizaPFCG_TESE.pdf: 3362653 bytes, checksum: 0de0a428d24980a5f9b2bf94d2e9214f (MD5) Previous issue date: 2012-08-23 / To overcome the challenge of meeting growing energy demand in a sustainable way, biodiesel has shown very promising as alternative energy can replace fossil fuels, even partially. Industrially, the biodiesel is produced by homogeneous transesterification reaction of vegetable oils in the presence of basic species used as catalysts. However, this process is the need for purification of the esters obtained and the removal of glycerin formed after the reaction. This context, the alternative catalysts have that can improve the process of biodiesel production, aiming to reduce costs and facilitate its production. In this study, the AlSBA-15 support with Si / Al ratio = 50 was synthesized, as like as the heterogeneous catalysts of zinc oxide and magnesium supported on mesoporous AlSBA-15 silica, in the concentrations of 5, 10, 15 and 30 %, relative to the support. The textural properties and structural characterization of catalysts and supports were determined by techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) coupled to the chemical analyzer, adsorption / desorption of N2, thermal analysis (TG / DTG), absorption spectroscopy in the infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). Characterization results indicated that the support AlSBA-15 retained the hexagonal ordered after the incorporation of zinc oxide and magnesium oxide in the holder. For heterogeneous catalysts, ZnO-AlSBA-15, that was observed the presence of zinc oxide nanoparticles dispersed in the surface and interior channels of the mesoporous and microporous support. The catalytic activity was evaluated by the transesterification reaction of sunflower oil via methylic route, and some reaction parameters were optimized with the most active catalyst in biodiesel production by sunflower oil. For the series of heterogeneous catalysts, the sample with 30 % ZnO supported on AlSBA-15 showed a better conversion of triglyceride to methyl esters, about 95.41 % of reaction conditions: temperature 175 ?C, with molar ratio of 42:1, stirring at 200 rpm and under a pressure of 14 bar for 6 h. The catalyst MgO-AlSBA-15 showed no catalytic activity in the studied reactions / Para superar o desafio de atender a crescente demanda por energia de forma sustent?vel, o biodiesel tem se demonstrado bastante promissor como alternativa energ?tica, que possa substituir os combust?veis fosseis, mesmo que parcialmente. Industrialmente, o biodiesel ? produzido atrav?s de rea??o homog?nea de transesterifica??o de ?leos vegetais na presen?a de esp?cies b?sicas utilizadas como catalisadores. Entretanto, este processo h? a necessidade de purifica??o dos ?steres obtidos e a remo??o da glicerina formada ap?s a rea??o. Diante deste contexto, tem-se buscado catalisadores alternativos, que possa aprimorar o processo de produ??o de biodiesel, visando diminuir os custos e facilitar a sua produ??o. Neste trabalho, foram sintetizados o suporte AlSBA-15 na raz?o Si/Al = 50, e os catalisadores heterog?neos de ?xido de zinco e de magn?sio suportado sobre s?lica mesoporosa AlSBA-15, nas concentra??o de 5, 10, 15 e 30 %, com rela??o ao suporte. As propriedades texturais e a caracteriza??o estrutural dos catalisadores e do suporte foram determinadas pelas t?cnicas de: difratometria de raios X (DRX), microscopia eletr?nica de varredura (MEV), microscopia eletr?nica de transmiss?o (MET) acoplada ao analisador qu?mico, adsor??o/dessor??o de N2, an?lise t?rmica (TG/DTG), espectroscopia de absor??o na regi?o do infravermelho (FTIR) e espectroscopia fotoeletr?nica de raios X (XPS). Os resultados de caracteriza??o indicaram que o suporte AlSBA-15 preservou a estrutura hexagonal ordenada, ap?s a incorpora??o do ?xido de zinco e do ?xido de magn?sio no suporte. Em rela??o aos catalisadores heterog?neos, ZnO-AlSBA-15, observou-se a presen?a de nanopart?culas de ?xido de zinco dispersas na superf?cie e no interior dos canais microporosos e mesoporosos do suporte. A atividade catal?tica foi avaliada pela rea??o de transesterifica??o do ?leo de girassol via rota met?lica, e alguns par?metros reacionais foram otimizados com o catalisador mais ativo na produ??o de biodiesel pelo ?leo de girassol. Para as s?ries de catalisadores heterog?neos, a amostra com 30 % ZnO suportado na AlSBA-15 apresentou melhor convers?o dos triglicer?deos em ?steres met?licos, cerca de 95,41 %, nas condi??es reacional de: temperatura de 175 ?C, com raz?o molar de 42:1, em agita??o de 200 rpm e sob press?o de 14 bar durante 6 h. O catalisador MgO-AlSBA-15 n?o apresentou atividade catal?tica nas rea??es estudadas