rOrientador: Martin Azna / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-22T13:28:41Z (GMT). No. of bitstreams: 1 SilvaJunior_JulioLopesda_M.pdf: 4182616 bytes, checksum: 6423419dacba1304ffd5dce09c359c97 (MD5) Previous issue date: 2013 / Resumo: O 2,5-dimetilfurano (DMF) é um biocombustível promissor que pode ser produzido a partir da desidratação da frutose por catálise ácida em um reator bifásico. Para o projeto, operação e otimização do processo de produção do DMF são indispensáveis dados de equilíbrio de fases, visando as etapas de separação e purificação, bem como dados de propriedades termofísicas dos componentes envolvidos, úteis no cálculo das propriedades de transporte. Entretanto, dados de equilíbrio líquido-líquido (ELL) envolvendo o DMF são, até o momento, inexistentes na literatura. Este trabalho teve como objetivo principal determinar experimentalmente dados de ELL de sistemas ternários água + DMF + solventes presentes nas etapas de separação do processo de produção do DMF em reator bifásico, bem como desenvolver a metodologia analítica mais apropriada. Foram usados como solventes 1-butanol, 2-butanol e 1- hexanol e as linhas de amarração foram obtidas nas temperaturas de 25°C e 40°C, a pressão atmosférica de aproximadamente 95,0 kPa. Três técnicas analíticas foram testadas: 1) densimetria e refratometria, 2) cromatografia gasosa com padronização interna e 3) cromatografia gasosa com titulação volumétrica de Karl Fischer, sendo empregada esta última metodologia na determinação da composição das fases em equilíbrio. O ELL do sistema ternário acetato de etila + 1-butanol + água a 20°C foi determinado e comparado com dados disponíveis na literatura para validação da metodologia analítica. Os resultados mostram que os sistemas estudados apresentam regiões de grande imiscibilidade e altos valores de seletividade para o DMF; portanto, estes álcoois foram considerados bons solventes para aplicação no processo de produção do DMF. Fez parte ainda dos objetivos do trabalho determinar as propriedades densidade, índice de refração e viscosidade do DMF puro, obtidos usando um densímetro de tubo em U vibrante, um refratômetro e um viscosímetro de bola em queda, respectivamente, em uma faixa de temperatura entre 15 e 60°C. Os dados de ELL obtidos foram satisfatoriamente correlacionados com o modelo NRTL para o cálculo do coeficiente de atividade, com desvio médio quadrático na composição menor que 2% para todos os sistemas; novos parâmetros de interação binária foram determinados nesta correlação. A qualidade dos dados experimentais foi verificada pelas equações de Bachman e Othmer-Tobias, que mostraram um coeficiente de correlação R2> 0,97 em todos os casos / Abstract: 2,5-Dimethylfuran (DMF) is a promising biofuel that can be produced by dehydration of fructose by acid catalysis in a biphasic reactor. For the design, operation and optimization of DMF production process, phase equilibrium data are necessary, aiming the separation and purification steps, as well as thermophysical properties of the involved compounds, useful in the calculation of transport properties. However, liquid-liquid equilibrium (LLE) data of systems including DMF are not available in the literature at the present time. The main objective of this work was to determine experimentally LLE data of ternary systems water + DMF + solvents present in the separation steps of DMF production process in biphasic reactor, as well to develop the most suitable analytical methodology. 1-Butanol, 2-butanol and 1-hexanol were used as solvents and the tie-lines were determined at 25°C and 40°C and at atmospheric pressure of about 95.0 kPa. Three analytical techniques were tested: 1) densimetry and refractometry, 2) gas chromatography with internal standard method and 3) gas chromatography combined with Karl Fischer volumetric titration, the latter used in the equilibrium phases composition determination. LLE data of ternary system ethyl acetate + 1-butanol + water at 20°C was determined and compared with those available in the literature for validation of the analytical methodology. The results show that the studied systems have large immiscibility region and high selectivity values for the DMF; therefore, these alcohols are considered good solvents for application in DMF process production. Also, new measurements of pure DMF density, refractive index and viscosity were performed, obtained by using a vibrating U-tube densimeter, a refractometer and a falling ball viscometer, respectively, in the temperature range 15 to 60°C. The obtained LLE data were satisfactorily correlated with the NRTL model for the activity coefficient calculation, with root mean square deviation in composition less than 2% for all systems; new binary interaction parameters were determined in this correlation. The quality of the experimental data was ascertained by Bachman and Othmer-Tobias equations, with a correlation coefficient R2 > 0.97 for all cases / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

Orientadores: Antonio José de Almeida Meirelles, Marcelo Lanza / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T03:18:50Z (GMT). No. of bitstreams: 1 FollegattiRomero_LuisAlberto_D.pdf: 1459960 bytes, checksum: 156264e9c23b646b44f0d820a5df70c7 (MD5) Previous issue date: 2011 / Resumo: Os esteres etilicos de acidos graxos (biodiesel) podem ser produzidos atraves da reacao da transesterificacao ou etanolise. Os reagentes (oleo vegetal e etanol), normalmente com o alcool adicionado em excesso para garantir uma maior conversao em esteres etilicos de acidos graxos (FAEEs), formam um mistura heterogenea com miscibilidade parcial, sendo necessario nesta etapa realizar agitacao no interior do reator para melhorar a difusao de componentes entre as fases formadas. Durante a reacao, a mistura inicial e transformada em outras duas fases, uma rica em esteres etilicos e outra rica em glicerina, com o etanol em excesso distribuindo¿se entre as duas fases. Finalmente, os esteres resultantes devem ser separados da glicerina, do alcool em excesso e do catalisador, via decantacao ou centrifugacao, seguido de um processo de lavagem com agua (purificacao) para eliminar os saboes, componentes graxos, restos de catalisador, alcool e glicerina. Algumas das dificuldades da producao industrial de biodiesel etilico estao associadas ao desconhecimento das composicoes das fases durante o processo reacional e a problemas adicionais na separacao de fases em funcao da maior presenca de etanol em ambas as fases resultantes da reacao. Por esta razao, torna¿se necessario o estudo do equilibrio liquido¿liquido das misturas envolvidas nas diferentes etapas do processo de producao deste biocombustivel. O presente trabalho teve como objetivo a determinacao de dados de equilibrio liquido¿liquido para uma serie de sistemas pseudo¿binarios e multicomponentes envolvendo oleos vegetais, FAEEs, etanol, glicerol e agua e a modelagem do equilibrio de fases destes sistemas empregando a equacao de estado CPA EoS (Cubic¿Plus¿Association Equation of State) e o modelo NRTL. Em uma primeira etapa, foi estudada a solubilidade dos reagentes: oleos vegetais + etanol em uma faixa de temperatura de 298,15 a 333,15 K. Estes dados foram correlacionados satisfatoriamente usando o modelo NRTL. Nesta modelagem, o oleo vegetal foi tratado como um pseudocomponente. A validade desta hipotese foi demonstrada em um trabalho subsequente sobre a particao dos triacilglicerois nas fases de equilibrio (oleosa e alcoolica) em misturas compostas de oleos vegetais + etanol para a producao de biodiesel. Na segunda etapa desta tese foram investigados sistemas ternarios relacionados com o periodo intermediario do processo reacional de producao de biodiesel: FAEEs + etanol + glicerol a 323,15 e 353,15 K. Estes dados foram correlacionados corretamente com a CPA EoS, aproveitando¿se a transferencia dos parametros usados num trabalho anterior na predicao do equilibrio liquido¿vapor de sistemas binarios compostos por esteres etilicos ou esteres metilicos de acidos graxos em uma faixa de pressao de 5332,9¿13332,23 Pa. Sistemas relacionados com a etapa de lavagem do biodiesel tambem foram investigados: FAEEs + etanol + agua a temperaturas entre 298,15 e 333,15 K. Os resultados mostraram que a lavagem com agua e uma maneira muito eficaz de recuperacao de etanol da fase rica em esteres gerados. Estes dados de equilibrio tambem foram correlacionados com a CPA EoS e os desvios medios apresentaram valores menores que 3,0 % / Abstract: Fatty acid ethyl esters (biodiesel) are produced through the transesterification reaction or ethanolysis. Reagents (vegetable oil and ethanol), usually with alcohol in excess to ensure a higher conversion into fatty acid ethyl esters (FAEEs), form a heterogeneous mixture with partial miscibility; in this step it is necessary to carry out agitation inside the reactor to improve component diffusion between the phases formed. During the course of the reaction, the initial mixture is transformed into two phases: an ethyl esters¿rich phase and the other a glycerin¿rich phase, with excess ethanol distributed in both phases. Finally, the esters must be separated from the glycerin, excess alcohol and catalyst, via decanting or centrifuging, followed by a washing process with water (purification) to remove the soaps, fatty compounds, residual catalyst, glycerin and alcohol. Some of the difficulties of industrial production of ethyl biodiesel are associated to the limited information about the phase compositions during the reaction process and additional problems during phase separations due to the high presence of ethanol in the two phases resulting of the reaction. For this reason, it becomes necessary studying the liquid¿liquid phase equilibrium of the mixtures involved in different steps of the production of this biofuel. The objective of this work was to determine the liquid-liquid equilibria data for several pseudo¿binary and multicomponent systems containing vegetable oils, FAEEs, ethanol, glycerol and water and the phase equilibrium modeling using the CPA EoS (Cubic¿Plus¿Association Equation of State) and NRTL model. In a first stage, the solubility of reagents (vegetable oil + ethanol) was studied in the temperature range from 298.15 to 333.15 K. These data were satisfactorily correlated using the NRTL model. In this model, the vegetable oil was treated as a pseudocomponent. The validity of this hypothesis was demonstrated in a subsequent work about the partition data of triacylglycerols between the two immiscible liquid equilibrium phases (oil and alcoholic) in vegetable oil + ethanol mixtures for biodiesel production. In the second stage of this thesis were investigated ternary systems related with the reaction process intermediate step of biodiesel production: FAEEs + ethanol + glycerol at 323.15 and 353.15 K. These data were correlated correctly with the CPA EoS, taking advantage of the transferability of the CPA parameters used in a previous work for predicting the vapor¿liquid equilibrium of binary systems composed of fatty acid ethyl or methyl esters in the pressure range 5332.9 ¿ 13332.23 Pa. Ternary systems related with the biodiesel washing process were also investigated: FAEEs + ethanol + water within the temperature range of 298.15 and 333.15 K. These results indicate that washing with water is a very effective way of extracting ethanol from the ester phase generated. These equilibrium data were also correlated with the CPA EoS and the mean deviation values were lower than 3.0 % / Doutorado / Engenharia de Alimentos / Doutor em Engenharia de Alimentos

Orientador: Maria Alvina Krahenbuhl / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T13:24:40Z (GMT). No. of bitstreams: 1 Mafra_MarcosRogerio_D.pdf: 5218448 bytes, checksum: 82785bbe534f8328a5b2d6c5c2a8c306 (MD5) Previous issue date: 2005 / Resumo: O estudo dos fenômenos físico-químicos presentes nos processos químicos industriais é de extrema relevância, desde o projeto ata a operação das unidades que compõem a planta. Dentre as etapas do processo, a separação e purificação costumam concentrar os maiores custos do projeto. Um importante segmento da indústria petroquímica é a produção de fenol, empregando na fabricação de resinas. Nesse processo duas colunas de destilação e um decantador são responsáveis pela purificação do fenol e recuperação da matéria-prima (cumeno). O equilíbrio de fases é um dos fenômenos mais importantes dessas unidades, havendo a possibilidade de ocorrer em alguns pratos o equilíbrio trifásico (LLV). Embora termodinamicamente possível, as tentativas de descrever essa forma de equilíbrio, utilizando dados exclusivamente bifásicos (LL /ou LV), não apresentam bons resultados. Este trabalho teve como objetivo o estudo termodinâmico do equilíbrio líquido-líquido e líquido-vapor na região próxima ao equilíbrio líquido-líquido-vapor de sistemas que compõem as etapas de separação do processo de produção fenol (água, acetona, 'alfa¿-metil estireno, cumeno e fenol), de forma a contribuir com o estudo do equilíbrio trifásico, presente nesse processo. Foram obtidos dados isotérmicos de equilíbrio líquido-líquido a 50 e ¿60 GRAUS¿C e dados isobáricos de equilíbrio líquido-vapor à 760 mmHg... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Studies concerning physical and chemical phenomena are very important for the chemical industry, form the early stages of design up to full plant operation. Among the many units that make up a chemical plant, the last steps of separation and purification stands as the most expensive. Phenol, used to produce resins as well as other products, is an important feedstock to petrochemical industries. Two distillations columns and one decanter are used to purify phenol and separate cumene in the phenol production process, in which phase equilibrium plays an important role. In a tray distillation tower, one may find two liquid phases and one vapor phase in equilibrium (VLLE). Although possible, attempts to describe this equilibrium condition from two phase equilibrium conditions, either liqui-liquid (LLE) or vapor-liquid (VLE), haven¿t succeed. The objective of this work was to study the LLE and VLE of systems comprising components of the phenol production process, i.e., water, acetone, cumene, phenol and 'alfa¿-methyl styrene, at conditions close to the liquid-liquid-vapor equilibrium. Equilibrium data were successfully obtained at ¿50 DEGREES¿C and ¿60 DEGREES¿C and at 760 mmHg for a variety of compositions. Unfortunately data at high acetone contents could not be obtained due to the high pressure generated in the experimental apparatus... Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

L'analyse radiochimique est indispensable à de nombreuses étapes de la gestion des déchets nucléaires et du contrôle de l’environnement. Un protocole d’analyse comprend généralement plusieurs étapes de séparations chimiques longues, manuelles et difficiles à mettre en œuvre en raison de leur confinement en boite à gants. Il est nécessaire de proposer des solutions innovantes et robustes pour automatiser ces étapes mais aussi réduire le volume de déchets radioactifs et chimiques en fin de cycle analytique. Une solution consiste à miniaturiser les analyses en les réalisant en laboratoire sur puce.L’objectif de cette thèse est de proposer une approche raisonnée de la conception de microsystèmes séparatifs dédiés à l’extraction liquide-liquide de radionucléides. Pour cela le comportement hydrodynamique et les performances d’extraction dans un même microsystème ont été étudiés pour les systèmes Eu(III)-HNO3/DMDBTDMA, Eu(III)-AcO(H,Na)-HNO3/HDEHP et U(VI)-HCl/Aliquat® 336. Une méthodologie a été mise au point pour l’implémentation de l’extraction liquide-liquide en microsystème pour chaque système chimique d’extraction et la comparaison des résultats a permis de mettre en évidence l’influence du rapport des viscosités des phases sur les écoulements. Grâce à la modélisation à la fois de l’hydrodynamique et du transfert de masse en microsystème, les critères liés aux propriétés physiques et cinétiques des systèmes chimiques ont été dégagés afin de proposer une conception rationnelle de microsystèmes à façon. Enfin plusieurs exemples de mises en œuvre de l’extraction liquide-liquide en microsystème pour des applications analytiques applicables dans le domaine du nucléaire comme la séparation U/Co ou le couplage microextraction liquide-liquide/ICP-MS sont décrits. / Radiochemical analyses are necessary to numerous steps for nuclear wastes management and for the control of the environment. An analytical protocol generally includes different steps of chemical separations which are lengthy, manual and complicated to implement because of their confinement in glove boxes and because of the hostile chemical and radiochemical media. Thus there is a huge importance to propose innovative and robust solutions to automate these steps but also to reduce the volumes of the radioactive and chemical wastes at the end of the analytical cycle. One solution consists in the miniaturization of the analyses through the use of lab-on-chip.The objective of this thesis work was to propose a rational approach to the conception of separation microsystems for the liquid-liquid extraction of radionuclides. To achieve this, the hydrodynamic behavior as well as the extraction performances have been investigated in one chip for three different chemical systems: Eu(III)-HNO3/DMDBTDMA, Eu(III)-AcO(H,Na)-HNO3/HDEHP and U(VI)-HCl/Aliquat® 336. A methodology has been developed for the implementation of the liquid-liquid extraction in microsystem for each chemical system. The influence of various geometric parameters such as channel length or specific interfacial area has been studied and the comparison of the liquid-liquid extraction performances has led to highlight the influence of the phases viscosities ratio on the flows. Thanks to the modeling of both hydrodynamics and mass transfer in microsystem, the criteria related to physical and kinetic properties of the chemical systems have been distinguished to propose a rational conception of tailor-made chips. Finally, several examples of the liquid-liquid extraction implementation in microsystem have been described for analytical applications in the nuclear field: U/Co separation by Aliquat® 336, Eu/Sm separation by DMDBTDMA or even the coupling between a liquid-liquid extraction chip and the system of detection which is the ICP-MS.

Beim Stoffübergang einer grenzflächenaktiven Substanz in einem flüssigen Zweiphasensystem kann solutale Marangoni-Instabilität einsetzen. Die weitere nichtlineare Entwicklung der Marangoni-Instabilität geht mit einer enormen Vielfalt von Strömungsmustern einher. In der Literatur wird dieser Aspekt häufig unter dem unscharfen Ausdruck „Grenzflächenturbulenz“ zusammengefasst. Diese Arbeit stellt heraus, dass drei grundlegende Strukturformen existieren: Rollzellen, Relaxationsoszillationen und Relaxationsoszillationswellen. Ein großer Teil der Komplexität der Strömungsmuster ist dadurch begründet, dass die Grundstrukturen unterschiedliche Hierarchieebenen aufweisen. Es werden die zugrunde liegenden Bedingungen für das Auftreten der jeweiligen Strukturtypen, ihre transiente Natur und die Bildung der hierarchischen Strömungsmuster untersucht. Des Weiteren betrachtet diese Arbeit die Wechselwirkungen mit Dichteeffekten, die sowohl die Charakteristik der Strukturen als auch ihre zeitliche Entwicklung beeinflussen.

This master's thesis deals with the analysis of biochar extracts by separation methods. All analyzed biochar was produced from waterworks sludge by microwave pyrolysis. The aim of the thesis is the optimization of the sample preparation method and its analysis in a laboratory environment. With the ever-growing world population, the problem of a sustainable economy in both agriculture and waste management is becoming increasingly urgent. This fact has led most countries to consider promoting the so-called Circular Economy. The use of sewage sludge as a feedstock for biochar production is perfectly in line with this strategy. So far, however, the short term and the long term benefits and risks of using biochar have not been sufficiently described. Potentially hazardous organic substances were extracted from the biochar extracts by three techniques: liquid-liquid extraction, solid-phase extraction, and solid- phase micro-extraction. The obtained samples were analyzed using the GS-MS/TOF method. The individual methods were compared. Several biochar samples from WWTP Brno and WWTP Drahovice were selected and analyzed to verify the suitability of the selected sample analysis method.

Introduction: Post-mortem whole blood samples differ greatly in quality, lipemia is one cause of concern in toxicological analyses. Around 4 % of all samples sent to RMV are given a notation of lipemic content. The aim of the thesis was to study the effects of lipemia on the quantification of 14 benzodiazepines and 5 similar sedative and antianxiety drugs as well as evaluate the pre-analytical process aiming to reduce the effects of lipemia.  Methods: Blood samples were simulated with bovine blood, analyte spiking, and lipid spiking with either the nutrition emulsion Intralipid or with a mixture of post-mortem lipids from authentic samples. The outset was the by RMV currently used LLE method followed by UPLC- MS/MS and the extraction method was altered and evaluated. Matrix effects were also studied.  Results: Lipemia were found to be a great interference when quantifying benzodiazepines. For most analytes, internal standard could compensate for the loss of analyte but there was a problem with analytes not having their own IS. The 7-amino-compounds were greatly affected by lipemia and propiomazine and dihydropropiomazine showed extreme losses. Equilibration of IS did not result in similar loss as analyte. Dilution of sample reduced losses caused by lipemic content. SPE resulted in extracts free from lipids and high yields but there were analyte losses similar to LLE. No matrix effects from the lipids were found. Samples spiked with Intralipid gave poorer analyte yields than those spiked with post-mortem lipids.  Conclusion: Dilution is the most successful method to reduce pre-analytical matrix effects as long as the concentration is not so low that it risks getting lower than the analytical limits when doing so. Not homogenising samples before sampling is giving incorrect results. SPE could, if optimised for the analyte retention and elution, remove lipids from samples and obtain accurate analyte concentrations. Pooling lipids from post-mortem samples is a possible method for simulating lipemic whole blood. Intralipid and the PM-mix gave the same indications, but to different extents. Further studies where the ability to mimic authentic lipids are needed for both Intralipid and PM-mix.

Cholesterol is an irreplaceable sterol found in animal cells, lathosterol is one of its precursors. The first aim of this Thesis is to develop a method for determining cholesterol after liquid- liquid extraction from milk matrices by differential pulse voltammetry on a boron doped diamond electrode in the presence of perchloric acid in acetonitrile where cholesterol provides an irreversible anodic response at the potential between +1300 and +1600 mV depending on the water content. The second aim is a study of the voltammetric behavior of lathosterol on boron doped diamond and glassy carbon electrodes using cyclic voltammetry and differential pulse voltammetry mainly in perchloric acid but also sodium perchlorate where lathosterol provides an irreversible anodic response at the potential of about +1650 mV on the boron doped diamond electrode and at the potential of +1350 mV on a glassy carbon electrode. The effect of other acids - sulfuric, nitric and phosphoric - on the response of lathosterol was also investigated. The influence of the water content in the measured solution and the influence of the polarization rate on the response of lathosterol were studied. Furthermore, the calibration dependence of lathosterol was measured using differential pulse voltammetry after optimization of its...

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Stem cells, with the ability to self-renew and differentiate into intended cell types, are a valuable tool for disease modeling and mechanistic study. CRISPR-Cas9 has been widely used for genome editing due to its high efficiency and convenience. However, CRISPR-Cas9 has large-deletion safety issues that dramatically restrict its applications. Wiskott-Aldrich syndrome (WAS) is an inborn immunological disorder caused by WASP deficiency. WASP functions in the nucleus, which may help to understand WAS pathology, are poorly defined. Pannexin 1 (PANX1) forms large plasma membrane pores to exchange intracellular small molecules with the extracellular environment and functions in inflammatory processes. The regulatory mechanisms of the PANX1 channel remain obscure. In this dissertation, I focused on mechanistic studies of CRISPR-Cas9 genome editing, and two immune disease relevant genes, WASP and PANX1 using stem cell-derived immune cells. We first found that CRISPR-induced large deletions (LDs) are predominantly mediated by the MMEJ repair pathway through statistical studies. Further, we found POLQ and RPA play vital roles in CRISPR-induced LDs. Modulation of POLQ and RPA can decrease CRISPR-induced LDs and increase HDR efficiency. Using three isogenic WAS iPSC models generated via gene editing, we successfully recapitulated WAS phenotypes, and for the first time, revealed that WASP regulates RNA splicing via epigenetically controlling the transcription of splicing factors and directly participating in the splicing machinery through a liquid-liquid phase separation process. We established a full-length human PANX1 (hPANX1) channel model via cryo-electron microscopy experiments and molecular dynamics simulation study, and found that hPANX1 channel is a homo-heptamer with both the N- and C-termini stretching deeply into the pore funnel. Functional studies of three selected residues support the new hPANX1 channel model and suggest the potential regulatory role of hPANX1 in pyroptosis upon immune responses. Overall, the mechanistic studies of WASP, PANX1 and CRISPR genome editing revealed new roles of WASP in regulating RNA splicing, new functional insights of PANX1 in pyroptosis, and uncovered two critical players POLQ and RPA in CRISPR-induced LDs.