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Prepara??o de resinas de poliuretana ? base de ?leo de mamona e dietanolaminaCardoso, Oldemar Ribeiro 30 October 2007 (has links)
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Previous issue date: 2007-10-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aim of this work was the preparation of polyols from reactions between castor oil and dietanolamine to increase the hydroxyl content and the network degree in the products to application in electronic devices. The polyols and the mixtures obtained were characterized by nuclear magnetic ressonance. Castor oil (CO) is a natural triglyceride - based polyol possessing hydroxyl groups, which allow several
reactions that produce many different products. Among them are the polyurethanes (PU), which have been considered an ideal product for the covering of electricelectronic circuits, due to their excellent electrical, shock-absorbing, solvents
resistance and hydrolytic stability properties. About 90% of the fatty acids present in the castor oil are ricinoleic acid (12-hydroxyoleic acid), while the remaining 10% correspond to non-hydroxylated fatty acids, mainly linoleic and oleic acids. The chemical analysis of castor oil indicates a hydroxyl number of 2.7. In this work, a polyol was obtained by the reaction of the CO with diethanolamine (DEA), in order to
elevate the hydroxyl value from 160 to 230 or to 280 mgKOH/g, and characterized by nuclear magnetic resonance (NMR) 1H and 13C (Mercury 200). The polyadition of the
resulting polyol with isophorone diisocianate (IPDI) was carried out at 60?C, and the reaction kinetics was followed by rheological measurements in a Haake RS150 rheometer. The electrical properties were determined in a HP LCR Meter 4262A, at 1.0 Hz and 10.0 KHz. The chemical analysis showed that the polyols obtained presented hydroxyl number from 230 to 280 mgKOH/g. The polyadition reaction with IPDI produced polyurethane resins with the following properties: hardness in the range from 45 shore A to 65 shore D (ASTM D2240); a dielectric constant of 3.0, at 25?C (ASTM D150). Those results indicate that the obtained resins present compatible properties to the similar products of fossil origin, which are used nowadays for covering electric-electronic circuits. Therefore, the PUs from castor oil can be considered as alternative materials of renewable source, free from the highly
harmful petroleum - derived solvents / O presente trabalho teve como objetivo a obten??o de poli?is a partir das rea??es do ?leo de mamona (OM) com dietanolamina (DEA), visando elevar o ?ndice de hidroxila e consequentemente o grau de reticula??o dos produtos finais, cuja aplica??o se destinou ao encapsulamento de circuitos eletroeletr?nicos. A caracteriza??o desses poli?is e respectivas misturas foram feitas utilizando-se a t?cnica da resson?ncia magn?tica nuclear (NMR). O OM (triglicer?deo do ?cido ricinoleico) ? um poliol vegetal natural por apresentar grupo funcional hidroxila que permite v?rias rea??es e produ??o de diferentes produtos. Entre eles est?o as
poliuretanas (PU) que t?m sido consideradas como produtos ideais para encapsulamento de componentes de circuitos eletro-eletr?nicos, devido as suas excelentes propriedades com rela??o ? resist?ncia mec?nica e qu?mica. As poliuretanas derivadas do ?leo de mamona podem ser consideradas materiais alternativos de fonte renov?vel e, para as produzidas neste trabalho, n?o foram empregados nenhum tipo de solvente. Cerca de 90% dos ?cidos graxos que
comp?em o ?leo de mamona s?o ?cido ricinoleico (?cido 12-hidroxioleico), enquanto os outros 10% s?o ?cidos graxos n?o hidroxilados (?cidos linoleico e oleico). As an?lises qu?micas do ?leo de mamona indicam uma funcionalidade m?dia de 2,7, em
rela??o aos grupos hidroxila. A poliadi??o entre o poliol resultante e o isocianato de isoforona (IPDI) teve sua cin?tica aco mpanhada com o aux?lio do re?metro Haake RS 150 ? temperatura de 60 ?C. As propriedades el?tricas foram determinadas em uma ponte HP LCR Meter 4262 A a 1,0 Hz e 10,0 KHz. As an?lises qu?micas mostraram que os poli?is obtidos apresentaram ?ndice de hidroxila entre 230 e 280
mgKOH/g. A rea??o de poliadi??o com IPDI produziu resinas de poliuretana com as seguintes propriedades: dureza entre 45 e 65 shore D (ASTM D2240); constante diel?trica de 3,0 a 25 ?C (ASTM D150). Os resultados, de um modo geral, indicaram que as resinas, cujo extensor de cadeia foi a DEA, apresentaram propriedades compat?veis e em muitos casos superiores, quando comparadas ?s dos produtos atualmente dispon?veis no mercado, sintetizados ? base de trietanolamina (TEA)
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An?lise qu?mica de produtos de incrusta??o em dutos de petr?leo por espectometria de fluoresc?ncia de raios XSena, Caio Patr?cio de Souza 28 July 2008 (has links)
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Previous issue date: 2008-07-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The quantitative chemical characterization of the inorganic fraction of scale products is very relevant in studying, monitoring and controlling corrosive processes of oil pipelines. The X-ray fluorescence spectrometry (XRF) is a very versatile
analytical technique, which can be used in quantitative analysis in solid samples at low concentrations of the chemical element, in the order of few ppm. A methodology
that involves sample preparation diluted in the proportion of 1:7 (one portion of the sample for seven of wax), pressed as pellets was used in the XRF calibration for chemical analysis of scale products from oil pipelines. The calibration involved the preparation of reference samples from mixtures of P.A. reagents, aiming to optimize the time consumed in the steps of sample preparation and analysis of Al, Ba, Ca,
Fe, K, Mg, Mn, Na, P, S, Si, Sr and Ti, using the same pressed pellet for trace and major elements analysis / A caracteriza??o qu?mica quantitativa da fra??o inorg?nica de produtos de incrusta??o ? de grande relev?ncia no estudo, monitoramento e controle de processos corrosivos em dutos de petr?leo. A espectrometria por fluoresc?ncia de
raios X (EFRX) ? uma t?cnica anal?tica muito vers?til, que pode ser utilizada na obten??o de resultados quantitativos de amostras s?lidas em baixas concentra??es do elemento qu?mico, da ordem de alguns ppm. Uma metodologia de prepara??o de amostras dilu?das na propor??o de 1:7 (uma por??o de amostra para sete de cera), posteriormente prensadas na forma de pastilhas foi utilizada na calibra??o do EFRX para an?lise de produtos de incrusta??o de dutos de petr?leo. O processo de calibra??o envolveu a confec??o de amostras de refer?ncia a partir de misturas de reagentes P.A., onde se buscou a otimiza??o do tempo envolvido nas etapas de prepara??o de amostras e an?lise dos elementos Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, S, Si, Sr e Ti, utilizando-se as mesmas pastilhas para dosagem de elementos tra?os
e maiores
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An?lise dos Processos de Flota??o e Oxida??o Avan?ada para o Tratamento de Efluente Modelo da Ind?stria do Petr?leo / Analysis of flotation and advanced oxidation processes for the treatment of a wastewater model of the petroleum industrySilva, Syllos Santos da 22 February 2010 (has links)
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Previous issue date: 2010-02-22 / The generation of wastes in most industrial process is inevitable. In the petroleum industry, one of the greatest problems for the environment is the huge amount of produced water generated in the oil fields. This wastewater is a complex mixture and present great amounts. These effluents can be hazardous to the environmental without adequate treatment. This research is focused in the analysis of the efficiencies of the flotation and photo-oxidation processes to remove and decompose the organic compounds present in the produced water. A series of surfactants derivated from the laurilic alcohol was utilized in the flotation to promote the separation. The experiments have been performed with a synthetic wastewater, carefully prepared with xylene. The experimental data obtained using flotation presented a first order kinetic, identified by the quality of the linear data fitting. The best conditions were found at 0.029 g.L-1 for the surfactant EO 7, 0.05 g.L-1 for EO 8, 0.07 g.L-1 for EO 9, 0.045 g.L-1 for EO 10 and 0.08 g.L-1 for EO 23 with the following estimated kinetic constants: 0.1765, 0.1325, 0.1210, 0.1531 and 0.1699 min-1, respectively. For the series studied, the most suitablesurfactant was the EO 7 due to the lower reagent consumption, higher separation rate constant and higher removal efficiency of xylene in the aqueous phase (98%). Similarly to the flotation, the photo-Fenton process shows to be efficient for degradation of xylene and promoting the mineralization of the organic charge around 90% and 100% in 90 min / A gera??o de res?duos na maioria dos processos industriais ? quase que inevit?vel. Na ind?stria do petr?leo, um dos grandes vil?es para o meio ambiente ? o enorme volume de ?guas produzidas nos campos de petr?leo. Este efluente apresenta composi??o complexa e aliado ao grande volume envolvido pode-se tornar bastante danoso ao meio ambiente quando descartado de forma inadequada. Esta pesquisa est? centrada na an?lise das efici?ncias dos processos de flota??o em coluna e oxida??o avan?ada por processo foto-Fenton para remo??o/degrada??o de org?nicos presentes na ?gua produzida. Uma s?rie de tensoativos derivados de ?lcool laur?lico
foi utilizada na flota??o para promover a melhoria da cin?tica e efici?ncia de separa??o. Os experimentos foram realizados com efluente sint?tico contendo xileno como poluente modelo. Os dados experimentais obtidos da flota??o apresentaram cin?tica de 1? ordem, identificada pela qualidade dos ajustes lineares. As melhores condi??es encontradas foram 0,029 g.L-1 para o EO 7, 0,05 g.L-1 para o EO 8, 0,07 g.L-1 para o EO 9, 0,045 g.L-1 para o EO 10 e 0,08 g.L-1 para o EO 23 com as seguintes constantes de velocidade iguais a 0,1765, 0,1325, 0,1210, 0,1531, 0,1699 min-1, respectivamente. Para a s?rie estudada, o tensoativo mais adequado foi o EO 7 devido o menor consumo de reagente, maior constante cin?tica de separa??o e maior
efici?ncia de remo??o do xileno da fase aquosa (98%). De forma similar a flota??o, o processo foto-Fenton demonstrou ser eficiente para degrada??o do xileno alcan?ando efici?ncia de
mineraliza??o da carga org?nica entre 90% e 100% em 90 min
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Craqueamento termocatal?tico de ?leo de girassol na presen?a da peneira molecular SAPO-5Oliveira, Ricardo Miguel de 06 December 2011 (has links)
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Previous issue date: 2011-12-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The catalytic cracking of triglycerides presents itself as a possible alternative to the
production of biofuels with low emission of pollutants. In this work were synthesized the
SAPO-5, the catalysts for the cracking reaction of soybean oil is presented. The solids were
powder X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG) and infrared
spectroscopy (FTIR). The analyses indicated that the synthesis method has employed to
obtain materials with high surface area and high acid. The soybean oil thermal and thermal
catalytic cracking, realized from the room temperature to 450 ?C in a simple distillation
system, has allowed obtaining two liquid fractions, each consisting of two phases, one
aqueous and another organic, organic liquid (OL). The OL obtained from first fractions has
shown high acid index, even in the thermal catalytic process. The products obtained in the
cracking of soybean oil were analyzed by distillation, acid number, infra-red spectroscopy,
density, viscosity, carbon residue, cetane number determination and characterization. The
analysis of the products obtained in the presence and in the absence of the SAPO-5 permitted
to conclude that all the solids tested presented catalytic activity in the deoxygenation of final
products only at the second step of the cracking process / O craqueamento catal?tico de triacilglicer?deos se apresenta como uma alternativa vi?vel para
a produ??o de biocombust?veis com baixa emiss?o de poluentes. Neste trabalho foi sintetizado
o SAPO-5, o catalisador foi utilizado na rea??o de craqueamento do ?leo de Girassol. O
s?lido foi caracterizado por difra??o de raios -X, an?lise termogravim?trica, espectroscopia no
infravermelho. As an?lises indicaram que atrav?s do m?todo de s?ntese empregado foram
obtidos materiais com elevada ?rea espec?fica e alta acidez. A partir do craqueamento t?rmico
e termocatal?tico do ?leo de girassol, realizado desde a temperatura ambiente at? 450 oC em
um sistema de destila??o simples, foram obtidas duas fra??es l?quidas, cada uma contendo
duas fases, uma aquosa e outra org?nica. A primeira fra??o do l?quido org?nico obtido
apresentou alto ?ndice de acidez, no processo de craqueamento t?rmico. Os produtos obtidos
no craqueamento de ?leo de Girassol foram analisados por destila??o, ?ndice de acidez,
espectroscopia no infravermelho, densidade, viscosidade e determina??o do ?ndice de cetano.
A an?lise dos produtos obtidos na presen?a e na aus?ncia do SAPO-5, sintetizados permitiu
concluir que todos os s?lidos testados apresentaram atividade catal?tica para a desoxigena??o
dos produtos finais apenas na segunda etapa do processo de craqueamento
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Estudo termoanal?tico da perlita hidrofobizada com ?leo de linha?aSouza, Hiale Yane Silva de 21 January 2010 (has links)
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Previous issue date: 2010-01-21 / In this work, expanded perlite, a mineral clay, consisting of SiO2 and Al2O3 in
the proportions of 72.1 and 18.5%, respectively, was used as an adsorbent for oil in
its pure expanded form as well as hydrofobized with linseed oil. Thermogravimetry
(TG), Derivative Thermogravimetry (DTG) and Differential Thermal Analysis (DTA)
were used to study the thermal behavior and quantify the percent adsorption of
perlite in differents processes comparing the results with the ones obtained using
Gravimetric Analysis. In the process of hydrophobization with linseed oil
granulometric fractions > 20, 20-32 and 32-60 mesh were used and adsorption tests
with crude oil were performed in triplicate at room temperature. The results obtained
by TG/DTG in dynamic atmosphere of air showed mass losses in a single step for the
expanded perlite with pure adsorbed oil, indicating that the adsorption of oil was
limited and that the particle size did not in this process. Linseed oil has performed
well as an agent of hydrophobized perlite (32 to 60 mesh) indicating a maximum
percentage of 59.9% and 68.6% the linseed with a fraction range from considering
the data obtained by thermogravimetry and Gravimetry, respectively. The adsorption
of oil in the expanded perlite and hydrofobized pure perlite with linseed oil did not
produce good results, characterizing an increase of 0.5 to 4.6% in pure perlite and
3.3% in hydrofobized perlite with granulometric 32 to 60 mesh / Nesse trabalho a perlita expandida, um argilomineral, constitu?do de SiO2 e
Al2O3 nas propor??es de 72,1 e 18,5%, respectivamente foi utilizada como
adsorvente para petr?leo na sua forma pura expandida como tamb?m hidrofobizada
com ?leo de linha?a. Para isso, utilizou-se a Termogravimetria (TG), a
Termogravimetria Derivada (DTG) e a An?lise T?rmica Diferencial (DTA) para
estudar o comportamento t?rmico e verificar o percentual de adsor??o da perlita nos
processos utilizados, em compara??o com a An?lise Gravim?trica. No processo de
hidrofobiza??o com o ?leo de linha?a utilizou-se as fra??es > 20, 20 a 32 e 32 a 60
mesh e os testes de adsor??o com o petr?leo bruto foram realizados em triplicata em
temperatura ambiente. Os resultados obtidos por TG/DTG em atmosfera din?mica
de ar mostraram perdas de massa em uma ?nica etapa para a perlita expandida
pura adsorvida com petr?leo, indicando que a adsor??o de petr?leo foi limitada e que
a granulometria n?o interferiu nesse processo. O ?leo de linha?a apresentou bons
resultados como agente hidrofobizante da perlita indicando um percentual m?ximo
de 59,9% e 68,6% de linha?a na fra??o de 32 a 60 mesh considerando os dados
obtidos por Termogravimetria e Gravimetria, respectivamente. A adsor??o do
petr?leo na perlita pura expandida e na perlita hidrofobizada com ?leo de linha?a n?o
apresentou bons resultados, caracterizando um aumento de 0,5 a 4,6% na perlita
pura e 3,3 % na perlita hidrofobizada de 32 a 60 mesh
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Obten??o de biodiesel atrav?s da transesterifica??o do ?leo de farelo de arroz utilizando KI/Al2O3Evangelista, Jo?o Paulo da Costa 25 February 2011 (has links)
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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
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Efici?ncia do processo de obten??o do biodiesel de girassol usando o catalisador KNO3/Al2O3Silva, J?lio C?sar Teixeira da 19 April 2012 (has links)
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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
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Novas formula??es de fluidos de corte: otimiza??o, propriedades e recupera??o do ?leo usadoMuniz, Cl?udia Alves de Sousa 12 November 2008 (has links)
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Previous issue date: 2008-11-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Cutting fluids are lubricants used in metal-mechanical industries. Their complex composition varies according to the type of operation carried out, also depending on the metals under treatment or investigation. Due to the high amount of mineral oil produced in Northeastern Brazil, we have detected the need to better use this class of material. In this work, two novel formulations have been tested, both based on naphthenic mineral oil and additives, such as: an emulsifying agent (A), an anticorrosion agent (B), a biocide (C) and an antifoam agent (D). Each formulation was prepared by mixing the additives in the mineral oil at a 700-rpm stirring velocity for 10 min, at 25?C, employing a 24 factorial planning. The formulations were characterized by means of density, total acid number (TAN), viscosity, flash point and anticorrosion activity. In a subsequent study, oil-in-water
emulsions were prepared from these novel formulations. The emulsions were analyzed in terms of stability, corrosion degree, percentage of foam formation,
conductivity, accelerated stability and particle size. The samples were appropriately labeled, and, in special, two of them were selected for featuring emulsion properties which were closer to those of the standards chosen as
references (commercial cutting oils). Investigations were undertaken on the ability of NaCl and CaCl2 to destabilize the emulsions, at concentrations of 2%, 5% and
10%, at an 800-rpm stirring velocity for 5 min and temperatures of 25?, 40?, 50? and 60?C. The recovered oils were chemically altered by reincorporating the same
additives used in the original formulations, followed by preparation of emulsions with the same concentrations as those of the initial ones. The purpose was to
assess the possibility of reusing the recovered oil. The effluents generated during the emulsion destabilization step were characterized via turbidity index, contents
of oil and grease, pH, and contents of anions and cations, observing compliance with the parameters established by the current environmental legislation (Brazil s CONAMA 357/05 resolution). It could be concluded that the formulations presented excellent physicochemical properties as compared to commercial cutting fluids, showing that the quality of the newly-prepared fluids is superior to that of the formulations available in the market, enabling technically and environmentally-safe applications / Fluidos de corte s?o lubrificantes usados nas ind?strias metal-mec?nicas. Possuem composi??es complexas que variam de acordo com o tipo de opera??o executada e com os metais a serem trabalhados. Levando-se em conta a grande quantidade de ?leo mineral produzido na regi?o nordeste, verificou-se a necessidade de melhor aproveit?-los. Neste trabalho desenvolveram-se duas
formula??es usando-se como base ?leo mineral naft?nico e aditivos, tais como: emulsificante (A), anticorrosivo (B), biocida (C) e antiespumante (D). Cada formula??o foi preparada com a mistura dos aditivos ao ?leo mineral, sob agita??o de 700 rpm por 10 min, a 25?C, utilizando-se um planejamento fatorial 24. As formula??es foram caracterizadas atrav?s da densidade, ?ndice de acidez, viscosidade, ponto de fulgor e corros?o. Em seguida foram preparadas emuls?es O/A obtidas a partir das novas formula??es. Destas emuls?es estudou-se a
estabilidade, grau de corros?o, percentual de espuma formado, condutividade, estabilidade acelerada e tamanho de part?culas. Escolheram-se as amostras F8 e
F16 por apresentarem as propriedades das emuls?es mais pr?ximas dos padr?es escolhidos como refer?ncia (fluidos de corte comerciais). Realizou-se o estudo da
quebra das emuls?es utilizando o NaCl e o CaCl2 , nas concentra??es de 2%, 5% e 10%, com agita??o durante 5 min, ? velocidade de 800 rpm, nas temperaturas
de 25?, 40?, 50? e 60?C. Os ?leos recuperados foram readitivados com os mesmos aditivos utilizados nas formula??es iniciais. Em seguida, prepararam-se
emuls?es nas mesmas concentra??es das emuls?es iniciais com o intuito de verificar se o ?leo recuperado poderia ser reutilizado. Os efluentes gerados
durante a quebra das emuls?es foram caracterizados atrav?s da turbidez, teor de ?leos e graxas, pH, ?nions e c?tions, verificando-se enquadramento dos par?metros avaliados na legisla??o ambiental em vigor (Resolu??o CONAMA 357/05). As formula??es apresentaram ?timas propriedades f?sico-qu?micas quando comparadas com os fluidos de corte comerciais, mostrando, dessa forma, que os fluidos obtidos s?o de qualidade superior aos encontrados no mercado e podem ser utilizados com seguran?a t?cnica e ambiental
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Remo??o, por flota??o, de ?leo em ?guas produzidas na ind?stria de petr?leo: efici?ncia e modelagem do processoAndrade, Jo?o Marconi de 30 March 2009 (has links)
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Previous issue date: 2009-03-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The separation oil-water by the use of flotation process is characterized by the involvement between the liquid and gas phases. For the comprehension of this process, it s necessary to analyze the physical and chemical properties command
float flotation, defining the nature and forces over the particles. The interface chemistry has an important role on the flotation technology once, by dispersion of a gas phase into a liquid mixture the particles desired get stuck into air bubbles, being conduced to a superficial layer where can be physically separated. Through the study of interface interaction involved in the system used for this work, was possible to apply the results in an mathematical model able to determine the probability of flotation using a different view related to petroleum emulsions such as oil-water. The
terms of probability of flotation correlate the collision and addition between particles of oil and air bubbles, that as more collisions, better is the probability of flotation. The additional probability was analyzed by the isotherm of absorption from Freundlich, represents itself the add probability between air bubbles and oil particles. The mathematical scheme for float flotation involved the injected air flow, the size of bubbles and quantity for second, the volume of float cell, viscosity of environment and concentration of demulsifier. The results shown that the float agent developed by castor oil, pos pH variation, salt quantity, temperature, concentration and water-oil quantity, presented efficient extraction of oil from water, up to 95%, using concentrations around 11 ppm of demulsifier. The best results were compared to other commercial products, codified by ―W‖ and ―Z‖, being observed an equivalent demulsifier power between Agflot and commercial product ―W‖ and superior to commercial product ―Z‖ / A separa??o ?leo/?gua pelo processo de flota??o ? caracterizada pelo envolvimento entre as fases l?quida e gasosa. Para a compreens?o desse processo,
? necess?rio estudar as propriedades f?sicas e qu?micas que governam a flota??o, estabelecendo a natureza e as for?as entre as part?culas. A qu?mica de interfaces desempenha um papel importante na tecnologia de flota??o, onde, por dispers?o de uma fase gasosa em uma mistura na fase l?quida, as part?culas a serem flotadas prendem-se ?s bolhas de ar e s?o conduzidas at? a camada superficial da solu??o,
onde s?o separadas fisicamente. Atrav?s do estudo das intera??es interfaciais envolvidas, foi poss?vel aplicar seus resultados em uma equa??o que determina a probabilidade de flota??o por uma nova ?tica relacionada ?s emuls?es de petr?leo do tipo ?leo/?gua. Os termos da probabilidade de flota??o correlacionam os fen?menos de colis?o e de ades?o entre as part?culas de ?leo e as bolhas de ar. Na probabilidade de colis?o observa-se que quanto maior o n?mero de colis?es maior a probabilidade de flota??o. A probabilidade de ades?o foi analisada atrav?s da isoterma de adsor??o de Freundlich, que representa a probabilidade de ades?o entre as bolhas de ar e as part?culas de ?leo. A modelagem matem?tica para a
flota??o envolveu o fluxo de ar injetado, o tamanho das bolhas de ar, a quantidade de bolhas por segundo, o volume da c?lula de flota??o, a viscosidade e a concentra??o do desemulsificante. Os resultados mostraram que o agente de
flota??o desenvolvido a partir do ?leo de mamona, ap?s a varia??o do pH, salinidade, temperatura, concentra??o de desemulsificante e teor de ?leo/?gua, apresentou uma efici?ncia de remo??o de ?leo em ?gua acima dos 95%, usando
uma concentra??o em torno de 11 ppm de desemulsificante. Os melhores resultados foram comparados com outros produtos comerciais, codificados por ―W‖ e ―Z‖, sendo observado um poder desemulsificante equivalente entre o Agflot e o produto comercial ―W‖ e superior ao produto comercial ‖Z‖
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Estudo do ?leo das sementes de Carthamus tinctorius L. Para produ??o de biodieselMorais, Ellen Kadja Lima de 20 September 2012 (has links)
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Previous issue date: 2012-09-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Most of the energy consumed worldwide comes from oil, coal and natural gas. These
sources are limited and estimated to be exhausted in the future, therefore, the search for
alternative sources of energy is paramount. Currently, there is considerable interest in making
trade sustainable biodiesel, a fuel alternative to fossil fuels, due to its renewable nature and
environmental benefits of its use in large scale. This trend has led the Brazilian government
to establish a program (Probiodiesel) with the aim of introducing biodiesel into the national
energy matrix, by addition of 5% biodiesel to conventional diesel in 2010 to foster not only
the increase of renewable energy, but reduce imports of crude oil. This work evaluates
different methods of extraction of oil Carthamus tinctorius L., their characterization by IR, 1H
and 13C NMR, HPLC and TG and their use in the production of methyl ester (molar ratio of
oil / alcohol 1:6, and NaOH catalyst). The physico-chemical parameters (acid value, density,
viscosity, saponification index and surface tension) of oil and biodiesel were also described.
The produced biodiesel had a yield of 93.65%, was characterized in relation to their physicochemical
properties showing satisfactory results (density=875 kg/m3, viscosity = 6.22 mm2/s,
AI = 0.01 mg (NaOH) /g) compared with the values established by the the National Agency
Oil, Natural Gas and Biofuels / A maior parte da energia consumida no mundo prov?m do petr?leo, do carv?o e do g?s
natural. Essas fontes s?o limitadas e com previs?o de esgotamento no futuro, portanto, a busca
por fontes alternativas de energia ? de suma import?ncia. Atualmente, h? um consider?vel
interesse em tornar sustent?vel o com?rcio do biodiesel, um combust?vel alternativo ao de
origem f?ssil, em fun??o de sua natureza renov?vel e dos benef?cios ambientais de seu
emprego em larga escala. Essa tend?ncia levou o governo brasileiro a estabelecer um
programa (Probiodiesel) com o objetivo de introduzir o biodiesel na matriz energ?tica
nacional, atrav?s da adi??o de 5% de biodiesel ao diesel convencional em 2010, de forma a
incentivar n?o somente o aumento de fontes renov?veis de energia, mas reduzir as
importa??es do ?leo bruto. O presente trabalho avalia diferentes m?todos de extra??es
(Soxhlet, Ultrassom e Exaustiva) do ?leo de Carthamus tinctorius L., sua caracteriza??o por
IV, RMN 1H e 13C, CLAE, TG e Estabilidade Oxidativa que na presen?a de antioxidante
demonstrou ser bastante satisfat?rio e seu emprego na produ??o de ?ster met?lico (raz?o molar
?leo/?lcool; 1:6; NaOH como catalisador). Os par?metros fisico-qu?micos (?ndice de acidez,
densidade, viscosidade, ?ndice de saponifica??o e tens?o superficial) do ?leo e biodiesel
tamb?m est?o descritos. O biodiesel produzido que apresentou rendimento de 93,65%, foi
caracterizado em rela??o as suas propriedades fisico-qu?micas apresentando resultados
satisfat?rios (Densidade = 875 kg/m3; Viscosidade = 6,22 mm2/s; IA = 0,01 mg (NaOH)/g)
quando comparados com os valores estabelecidos pela Ag?ncia Nacional do Petr?leo, G?s
Natural e Biocombust?veis
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