Orientadores: Reginaldo Guirardello, Lucio Cardozo-Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-09T05:19:46Z (GMT). No. of bitstreams: 1 Jesus_LorenaBrancagliaode_M.pdf: 1007051 bytes, checksum: 2881509687072c829010312b1b5653e0 (MD5) Previous issue date: 2007 / Resumo: O conhecimento do equilíbrio de fases é de grande importância no projeto e análise de uma grande variedade de processos químicos, incluindo reatores e unidades de separação. É o caso, por exemplo, da indústria de produção de óleos vegetais e de produção de ácido cítrico. Geralmente, sistemas de interesse da indústria alimentícia são formados por muitos componentes. A determinação e o cálculo das propriedades termodinâmicas e do equilíbrio de fases, nesses casos, são bastante complicados. Devido à natureza não-convexa e não-linear de modelos termodinâmicos, necessários para descrever o problema do equilíbrio de fases, há um grande interesse na aplicação de técnicas de otimização para descrever o comportamento do equilíbrio. Problemas de otimização global, técnicas rápidas, seguras e robustas que têm certo grau de confiança para achar a solução global não foram ainda completamente desenvolvidos. Por isso, estudos desses métodos têm sido foco na simulação e otimização na engenharia química. Este trabalho tem como objetivo o estudo e aplicação de um método de busca estocástica para otimização global no cálculo do equilíbrio de fases de misturas complexas de sistemas de interesse da industria alimentícia. O método de busca estocástica utilizado é o algoritmo ¿simulated annealing¿ (SA) devido à sua principal vantagem em poder evitar mínimos locais (teoricamente) e de ser de fácil aplicação. A determinação do equilíbrio de fases é feita pela minimização da energia livre de Gibbs do sistema. Para a representação termodinâmica de misturas complexas de interesse da indústria alimentícia foram empregados os modelos NRTL (Non-Random-Two-Liquid) e UNIQUAC (UNIversal QUAsi-Chemical). Os dados experimentais utilizados como estudo de caso foram obtidos na literatura e foram caracterizados por meio de pseudo-componentes, uma vez que são formados por muitas substâncias diferentes. Os resultados obtidos para os casos estudados demonstraram que a aplicação da técnica de SA para minimização global da energia livre de Gibbs permite, juntamente com os modelos NRTL e UNIQUAC, a representação confiável dos dados experimentais em tempos muito bons de execução. Além disso, a técnica de SA mostrou-se robusta levando a resultados de mínimo global independentemente da estimativa inicial, mesmo para casos fortemente não-lineares e não-convexos / Abstract: In many industrial processes, during the phase of refining and separation, products form very complex mixtures. It is the case, for example, of the vegetal oil and citric acid industries. As these mixtures are formed by many components, determination and calculation of thermodynamic properties and phase equilibrium are very complicated. In this way, the use of the most rigorous methods able to calculate the phase equilibrium and to analyse the stability of phases of these mixtures becomes necessary. In this work, the determination of phase equilibrium is done by minimization of the Gibbs free energy of the system. The NRTL (Non-Random-Two-Liquid) and UNIQUAC (UNIversal QUAsi-Chemical) models were used for the thermodynamic representation of the complex mixtures, which were characterized by means of pseudo-components. Under conditions of constant temperature and pressure, the necessary and sufficient condition for a multiphase and multicomponent system to reach the equilibrium is that the Gibbs free energy is a global minimum. Based on this principle, equilibrium problems can be formulated and solved as otimization problems. The objective function for these problems is generaly highly nonlinear and usually nonconvex, and methods of global optimization are generally necessary for its minimization. The technique of global optimization studied and applied in this work is a method of random search named Simulated Annealing (SA), whose main advantages are the ability to avoid local minimum and the ease of application. The results obtained for the studied cases have demonstrated that the application of the technique of SA for global minimization of the Gibbs free energy, together with the models NRTL and UNIQUAC, allows a reliable representation of the experimental data in very short execution times. Moreover, the SA technique was robust, leading to the global minima independently of the initial estimate even for highly nonlinear and nonconvex cases / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

Orientador: Fernando Antonio Cabral / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T13:55:53Z (GMT). No. of bitstreams: 1 Gomes_DanielaCaioAndre_M.pdf: 2263142 bytes, checksum: 6a08300201853fde99cabfc0824e3b26 (MD5) Previous issue date: 2011 / Resumo: Corrigiu-se empiricamente o parâmetro a da equação de estado de Peng-Robinson para o CO2 em função da temperatura e pressão, para que a equação pudesse calcular corretamente a fugacidade do dióxido de carbono em condições supercríticas. Em princípio, o intuito foi verificar se a modelagem termodinâmica com esta correção poderia correlacionar melhor os dados de equilíbrio de fases de sistemas constituídos de dióxido de carbono supercrítico e substâncias de interesse presentes em alimentos. Para testar esta hipótese, os seguintes sistemas bifásicos constituídos de dióxido de carbono supercrítico e componentes graxos foram selecionados da literatura: CO2 ¿ esqualeno, CO2 ¿ ácido oleico, CO2 ¿ tricaprilina, CO2 ¿ éster etílico de EPA, CO2 ¿ éster etílico de DHA, CO2 ¿ alfa-tocoferol, CO2 ¿ alfa-tocoferol, CO2 ¿ trioleína, CO2 ¿ tripalmitina. Tais escolhas são decorrentes do crescente interesse de se recuperar esses componentes minoritários de óleos brutos ou dos subprodutos resultantes do processamento convencional de óleos e gorduras, devido a sua importância na manutenção da saúde humana. Além disso, tem crescido o interesse por produtos naturais isentos de solventes orgânicos indesejáveis. Nesse sentido, os processos de extração com dióxido de carbono supercrítico vêm suprir esta demanda atual, pois é um solvente inerte que não agride o meio ambiente. Os resultados mostraram que as propriedades críticas que são estimadas por métodos de contribuição de grupos influenciaram mais no desempenho da modelagem termodinâmica que a correção do parâmetro a da equação de estado de Peng-Robinson. As maiores correções do parâmetro foram obtidas nas condições de maiores valores de temperatura e menores de pressão. No geral, a correção do parâmetro a não diminuiu o desvio em relação aos valores experimentais quando comparados aos valores obtidos sem a correção do parâmetro. No entanto, em alguns sistemas observou-se que a correção deste parâmetro para as condições de pressões elevadas modificou o comportamento dos valores de solubilidade calculados, produzindo valores mais próximos aos experimentais / Abstract: Corrected empirically the parameter a of the Peng- Robinson equation of state of for CO2 as a function of temperature and pressure, so that the equation could correctly calculate the fugacity of carbon dioxide in supercritical conditions. In principle, the aim was to verify whether the thermodynamic modeling with this correction could better correlate the phase equilibrium data from system consisting of supercritical carbon dioxide and substances of interest in food. To test this hypothesis, the following two-phase systems consisting of supercritical carbon dioxide and fatty components were selected from the literature: CO2 - squalene, CO2 - oleic acid, CO2 - tricaprylin, CO2 - ethyl ester of EPA, CO2 - DHA ethyl ester, CO2 - ?-tocopherol, CO2 - ?-tocopherol, CO2 - triolein, CO2 - tripalmitin. Such choices are the result of growing interest to recover these minor components of crude oils or byproducts resulting from conventional processing of oils and fats, due to its importance in maintaining human health. In addition, interest has grown in natural products free of undesirable organic solvents. In this sense, the processes of extraction with supercritical carbon dioxide come meet this current demand, it is an inert solvent that does not harm the environment. The results showed that the critical properties are estimated by group contribution methods of influence over the performance of thermodynamic modeling that the correction of the parameter to the equation of state of Peng-Robinson. The larger corrections of the parameter were obtained under conditions of higher temperatures and under pressure. In general, the correction of the parameter a does not diminish the deviation from the experimental values when compared to values obtained without the correction parameter. However, in some systems it was observed that the correction of this parameter for the conditions of high pressures changed the behavior of the solubility values calculated, yielding values closer to experimental / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos

L'objectif principal de ce travail est le développement d'une équation d’état précise pour la détermination des propriétés thermodynamique de mélange de gaz riche en gaz acides (CO2, H2S) contenant des hydrocarbures et autres gaz (impuretés) comme N2, O2, Ar, etc présente lors du stockage du CO2 (CCS). Après comparaisons avec des données expérimentales, nous avons retenu le modèle SAFT-VR Mie qui prédit de manière satisfaisante les masses volumiques pour les composés purs et les équilibres entre phases. Trois types de propriétés de transport ont également été prédites avec le modèle thermodynamique SAFT-VR Mie associé avec deux autres modèles de prédiction des propriétés de transport (TRAPP et DGT). La prédiction de ces propriétés de transport (viscosité et tension superficielle) repose sur une estimation la plus précise possible des masses volumiques. Pour compléter les banques données expérimentales, les équilibres liquide-vapeur concernant le système binaire H2S-Ar ont été déterminés à l'aide d'un dispositif de mesure dont la méthode technique repose sur la méthode "statique analytique" avec échantillonnage des phases (échantillonneur capillaire ROLI). Déplus, à l'aide d'un densimètre à tube vibrant, les masses volumiques de cinq systèmes binaires (H2S - hydrocarbures (méthane, éthane et propane) ont été mesurées. Les masses volumiques d'un système ternaire (CO2/CH4/H2S) et les masses volumiques et les viscosités d'un mélange multi-constituant riche en CO2 ont aussi été mesurées. Les données sont parfaitement représentées par les modèles développés au cours de cette thèse. / The main aim of this research is to develop a thermodynamic model from an accurate equation of state (EoS) for CO2, hydrocarbons and other gases as N2, O2, Ar, etc. The SAFT-VR Mie EoS was selected to study the phase behaviour and transport properties of mixtures related to carbon capture and storage (CCS). In order to asses this new version of SAFT, several equations of state have been compared (PR, SRK and PC-SAFT). SAFT-VR Mie EoS provides very good density predictions for pure component and binary systems according to the comparative study carried out. Therefore, three transport properties were modelled with SAFT-VR Mie and two models based on density predictions from the EoS. Thus, density, viscosity and interfacial tension (IFT) of CO2-rich systems were calculated by this SAFT-EoS (density), TraPP model (viscosity) and DGT (IFT), in the framework of CCS. Some experimental work was done, in order to extend the available literature data. Isothermal vapor-liquid equilibrium of H2S-Ar binary system was determined at three temperatures from 258 to 288 K. Densities of five binary systems of H2S with methane, ethane and propane were measured continuously at 3 temperatures (253, 273 and 293K) and at pressures up to 30MPa. Following the same technique, the density of the ternary system 42%CO2, 40%CH4 and 18%H2S was measured at pressures ranging from 0.2 to 31.5MPa and at 6 temperatures between 253 and 353K. Densities and viscosities of a multicomponent CO2-rich with 50% of impurities were measured at 5 temperatures between 283 and 423 K and at pressures up to 150 MPa.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22777号 / 工博第4776号 / 新制||工||1747(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 乾 晴行, 教授 安田 秀幸, 教授 辻 伸泰 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Alterations of fluid phase transitions in porous materials are conventionally employed for the characterization of mesoporous solids. In the first approximation, this may be based on the application of the Kelvin equation for gas–liquid and the Gibbs–Thomson equation for solid–liquid phase equilibria for obtaining pore size distributions. Herein, we provide a comparative analysis of different phase coexistences measured in mesoporous silica solids with different pore sizes and morphology. Instead of comparing the resulting pore size distributions, we rather compare the transitions directly by using a common coordinate for varying the experiment’s thermodynamic parameters based on the two equations mentioned. Both phase transitions in these coordinates produce comparable results for mesoporous solids of relatively large pore sizes. In contrast, marked differences are found for materials with smaller pore sizes. This illuminates the fact that, with reducing confinement sizes, thermodynamic fluctuations become increasingly important and different for different equilibria considered. In addition, we show that in the coordinate used for analysis, mercury intrusion matches perfectly with desorption and freezing transitions.

In this paper we formulate a nonlocal density functional theory of inhomogeneous water. We model a water molecule as a couple of oppositely charged sites. The negatively charged sites interact with each other through the Lennard–Jones potential (steric and dispersion interactions), square-well potential (short-range specific interactions due to electron charge transfer), and Coulomb potential, whereas the positively charged sites interact with all types of sites by applying the Coulomb potential only. Taking into account the nonlocal packing effects via the fundamental measure theory, dispersion and specific interactions in the mean-field approximation, and electrostatic interactions at the many-body level through the random phase approximation, we describe the liquid–vapour interface. We demonstrate that our model without explicit account of the association of water molecules due to hydrogen bonding and with explicit account of the electrostatic interactions at the many-body level is able to describe the liquid–vapour coexistence curve and the surface tension at the ambient pressures and temperatures. We obtain very good agreement with available in the literature MD simulation results for density profile of liquid–vapour interface at ambient state parameters. The formulated theory can be used as a theoretical background for describing of the capillary phenomena, occurring in micro- and mesoporous materials.

This cumulative dissertation is a compendium of five peer-reviewed and published scientific papers on developing an advanced NMR Cryoporometry toolbox for pore architecture characterization. The dissertation contains five chapters. The first introduces porous materials, their types and applications. Chapter two describes the fundamentals of fluid phase equilibria in mesoporous solids and how modifications of the well-known Laplace equation describe various fluid phase equilibria. The basic principles of the Gas Sorption and NMR Cryoporometry techniques are discussed. In chapter three, different characterization techniques are amalgamated onto a common framework which can be used to compare fluid phase coexistence in porous materials of different pore sizes. Chapter four explains a completely new NMR Cryoporometry characterization methodology developed for cylindrical and spherical pore shapes. Chapter five concludes and crowns the present work by discussing the complementary benefits of the advanced technique in characterizing random porous materials and accounting for pore connectivity effects. All materials synthesized for the work in this dissertation have been obtained through collaborations with the groups of Profs. Dr. Michael Fröba and Simone Mascotto of the Hamburg University and Prof. Dr. Dirk Enke of the Leipzig University.:Table of Contents Thesis Summary ........................................................................................................1 List of publications ......................................................................................................2 Acknowledgements ...................................................................................................4 CHAPTER 1:.............................................................................................................10 Introduction ..............................................................................................................10 CHAPTER 2:.............................................................................................................12 Fluid Phase Equilibria in Mesoporous Solids ..........................................................12 2.1 Gas Sorption................................................................................................... 13 2.1.1 Adsorption Isotherms................................................................................ 15 2.1.2 Adsorption Hysteresis............................................................................... 18 2.1.3 Scanning Behavior.................................................................................... 23 2.2 NMR Cryoporometry ....................................................................................... 25 2.2.1 Pore Size Distribution (PSD)....................................................................... 28 2.3 Serially-Connected Pore Model (SCPM)......................................................... 29 2.4 Problem Statement ......................................................................................... 30 CHAPTER 3:..............................................................................................................32 Analogy between Characterization Techniques ......................................................32 • Publication 3. On the Comparative Analysis of Different Phase Coexistences in Mesoporous Materials CHAPTER 4:.............................................................................................................42 An Advanced NMR Cryoporometry Approach.........................................................42 • Publication 4.1. Nuclear Magnetic Resonance Cryoporometry Study of Solid−Liquid Equilibria in Interconnected Spherical Nanocages • Publication 4.2. A novel approach for advanced thermoporometry characterization of mesoporous solids: Transition kernels and the serially connected pore model CHAPTER 5:.............................................................................................................65 Characterizing Random Porous Materials................................................................65 • Publication 5.1. Comparative Gas Sorption and Cryoporometry Study of Mesoporous Glass Structure: Application of the Serially Connected Pore Model • Publication 5.2. Impact of Geometrical Disorder on Phase Equilibria of Fluids and Solids Confined in Mesoporous Materials Appendix A:.............................................................................................................100 Porous Solid Characterization Techniques............................................................100 A.1: Mercury Intrusion Porosimetry (MIP) ........................................................... 100 A.1.1. Experimental Set-up.............................................................................. 101 A.2: Gas Sorption................................................................................................ 103 A.2.1. Experimental Set-Up ............................................................................. 103 A.2: NMR Cryoporometry.................................................................................... 106 A.2.2. Experimental Set-Up ............................................................................. 106 Appendix B:..............................................................................................................109 Supporting information ............................................................................................109 Appendix C:.............................................................................................................115 Author contributions ................................................................................................115 Bibliography ............................................................................................................117

Nuclear magnetic resonance (NMR) provides a variety of tools for the structural characterization of porous solids. In this paper, we discuss a relatively novel approach called NMR cryodiffusometry, which is based on a simultaneous assessment of both the phase state of intraporous liquids at low temperatures, using NMR cryoporometry, and their transport properties, using NMR diffusometry. Choosing two model porous materials with ordered and disordered pore structures as the host systems, we discuss the methodological and fundamental aspects of the method. Thus, with the use of an intentionally micro-structured mesoporous silicon, we demonstrate how its structural features give rise to specific patterns in the effective molecular diffusivities measured upon progressive melting of a frozen liquid in the mesopores. We then present the results of a detailed study of the transport properties of the same liquid during both melting and freezing processes in Vycor porous glass, a material with a random pore structure. 1

Die Frage nach der Möglichkeit von Leben auf anderen Planeten, vor allem auf dem Mars, steht in einem engen Zusammenhang mit der Verfügbarkeit von flüssigem Wasser. Dies ist bei den vorherrschenden klimatischen Bedingungen, vor allem der tiefen Temperatur, nur mittels einer Gefrierpunktserniedrigung durch Salze erklärbar. Die vorliegende Arbeit beschäftigt sich daher mit Phasengleichgewichten verschiedener Salz-Wasser-Systeme bei tiefen Temperaturen. Dabei wurden nach einer Sammlung von Literaturdaten und einer Ermittlung der Lücken innerhalb dieser verschiedene Systeme nach Mars-Relevanz, sowie chemischer Systematik ausgewählt und experimentell untersucht. Insgesamt wurden dabei 22 binäre Phasendiagramme von Salz-Wasser-Systemen betrachtet und 29 festen Phasen mittels Röntgen-Einkristallstrukturanalyse aufgeklärt. Aus diesen Strukturen wurde ein Modell zur Beschreibung einer zweiten Hydratationssphäre über eine Wechselwirkungsbilanz abgeleitet und an den verfügbaren Strukturen geprüft.

Ce travail est consacré à l’étude du procédé de synthèse, d’extraction et de purification d’une hydrazine exocyclique à applications cosmétiques, la N-aminopyrrolidine (NAPY). Dans un premier temps, l’optimisation des conditions de synthèse par la voie Raschig e été conduite en étudiant l’influence de deux paramètres, rapport molaire des réactifs (NH2Cl, pyrrolidine) et la température, sur le rendement de la réaction. Les solutions brutes de synthèse étant très diluées (≈5%g en NAPY), l’extraction et la purification du produit utile sont souvent liées à des opérations successives de démixtion et de distillation. La détermination de ces conditions de séparation requière alors la connaissance des propriétés thermodynamiques des équilibres entre phases impliqués dans ces opérations unitaires. L’optimisation de la démixtion nécessite alors l’étude du système ternaire solide-liquide-liquide NaOH/Pyrrolidine/Eau. Trois coupes isothermes isobares ont été complètement déterminées, par ATI (Analyse Thermique Isopléthique) combinée à des dosages chimiques. La méthode du diamètre et des modules a été mise au point pour la détermination du point critique de la courbe de démixtion. Les opérations de distillation mettent en jeu le système ternaire NAPY/Pyrrolidine/Eau. Le binaire limite liquide-vapeur Eau/Pyrrolidine a été déterminé par ébulliométrie à la pression atmosphérique. Pour essayer de mieux comprendre les interactions hétéromoléculaires ayant lieu en phase liquide, deux autres binaire liquide-vapeur eau/amine ont été obtenus. L’étude su système ternaire liquide-vapeur nous a permis de déduire deux schémas de distillation possibles. Une fois les conditions de synthèse et d’extraction définies et un schéma de procédé a été proposé, la NAPY est obtenue conforme aux spécifications cosmétiques / This global work is related to the synthesis, extraction and purification of a new exocyclic hydrazine with cosmetic applications, the N-aminopyrrolidine (NAPY). Firstable, the optimization of the synthesis conditions by the Raschig way are carried out by studying the influence of two parameters, the reagents’ molar ratio and the temperature, on the yield of the reaction. Due to the very low hydrazine content in the reaction liquors (≈5%w of NAPY), the extraction and purification of the useful product are often linked to successive demixing and distillation operations. The determination of these separation conditions requires then the knowledge of thermodynamics’ properties of the phase equilibria in these unitary steps. The optimization of the demixing needs then the study of the solid-liquid-liquid ternary solution NaOH/Pyrrolidine/Water. In this aim, three isothermal isobaric sections were studied, by combination of ATI (Isoplethic Thermal Analysis) and chemical analysis. The diameter and modulus method was developed in order to determine the composition of the critical point of the demixing curve. The distillation steps involve the liquid-vapor ternary system NAPY/Pyrrolidine/Water. The limit binary system Water/Pyrrolidine was determined by ebulliometry under atmospheric pressure. For a better understanding of the heteromolecular interactions in the liquid phase, two others liquid-vapor binary systems Water/Amine were obtained. The study of the ternary liquid-vapor system lad us to deduce two various distillation schemes. Once the synthesis and extraction conditions defined, a global process scheme was proposed, and NAPY was obtained in conformity with the cosmetical specifications