Thermodynamic properties are essential for the design of chemical processes, and they are most useful in the form of an equation of state (EOS). The motivating force of this work is the need for accurate prediction of the phase behavior and thermophysical properties of natural gas for practical engineering applications. This thesis presents a new cubic EOS for pure argon. In this work, a theoretically based EOS represents the PVT behavior of pure fluids. The new equation has its basis in the improved Most General Cubic Equation of State theory and forecasts the behavior of pure molecules over a broad range of fluid densities at both high and low pressures in both single and multiphase regions. With the new EOS, it is possible to make accurate estimations for saturated densities and vapor pressures. The density dependence of the equation results from fitting isotherms of test substances while reproducing the critical point, and enforcing the critical point criteria. The EOS includes analytical functions to fit the calculated temperature dependence of the new EOS parameters.

Thermodynamic properties are essential for the design of chemical processes, and they are most useful in the form of an equation of state (EOS). The motivating force of this work is the need for accurate prediction of the phase behavior and thermophysical properties of natural gas for practical engineering applications. This thesis presents a new cubic EOS for pure argon. In this work, a theoretically based EOS represents the PVT behavior of pure fluids. The new equation has its basis in the improved Most General Cubic Equation of State theory and forecasts the behavior of pure molecules over a broad range of fluid densities at both high and low pressures in both single and multiphase regions. With the new EOS, it is possible to make accurate estimations for saturated densities and vapor pressures. The density dependence of the equation results from fitting isotherms of test substances while reproducing the critical point, and enforcing the critical point criteria. The EOS includes analytical functions to fit the calculated temperature dependence of the new EOS parameters.

A descoberta de petróleo na camada de Pré-Sal possibilita a geração de ganhos em relação à dependência energética do país, mas também grandes desafios econômicos e tecnológicos. Os custos de extração são maiores devido a vários fatores como a exigência de equipamentos de exploração que suportem elevadas pressões, altas temperaturas e grandes concentrações de gases ácidos, tais quais, dióxido de carbono (CO2) e sulfeto de hidrogênio (H2S). Uma das principais preocupações com o CO2 é evitar liberá-lo para a atmosfera durante a produção. Com a modelagem termodinâmica de dados de equilíbrio de sistemas envolvendo CO2 supercrítico e hidrocarbonetos é possível projetar equipamentos utilizados em processos de separação. A principal motivação do trabalho é o levantamento de dados de equilíbrio de fases de sistemas compostos de CO2 e hidrocarbonetos, possibilitando assim prever o comportamento dessas misturas. Os objetivos específicos são a avaliação do procedimento experimental, a estimação e predição dos parâmetros de interação binários para assim prever o comportamento de fases dos sistemas ternários envolvendo CO2 e hidrocarbonetos. Duas metodologias foram utilizadas para obtenção dos dados de equilíbrio: método estático sintético (visual) e método dinâmico analítico (recirculação das fases). Os sistemas avaliados foram: CO2 + n-hexano, CO2 + tetralina, CO2 + n-hexadecano, CO2 + n-hexano + tetralina e CO2 + tetralina + n-hexadecano à alta pressão; tetralina + n-hexadecano à baixa pressão. Para o tratamento dos dados foi utilizada equação de estado cúbica de Peng-Robinson e a regra de mistura clássica / The discovery of oil in the pre-salt layer enables the generation of earnings in relation to the energy dependence of the country, but also large economic and technological challenges. Extraction costs are higher due to various factors such as the demand for mining equipment capable of withstanding high pressures, high temperatures and high concentrations of acid gases, as such, carbon dioxide (CO2) and hydrogen sulfide (H2S). A major concern with CO2 is to avoid releasing it into the atmosphere during production. With the thermodynamic equilibrium modeling systems involving data supercritical CO2 and hydrocarbon is possible to design equipment used in separation processes. The main motivation is the data collection phase equilibrium compounds CO2 systems and hydrocarbons, thus enabling predict the behavior of these mixtures. The specific objectives are to assess the experimental procedure, the estimation and prediction of binary interaction parameters so as to predict the behavior of phases of ternary systems involving CO2 and hydrocarbons. Two methodologies were used to obtain the equilibrium data: synthetic static method (visual) and analytical dynamic method (recycling phase). The systems were evaluated: CO2 + n-hexane, CO2 + tetralin, CO2 + n-hexadecane, CO2 + n-hexane + tetralin, and CO2 + tetralin + n-hexadecane at high pressure; tetralin + n-hexadecane at low pressure. For the treatment of the data was used cubic equation of state of Peng-Robinson and the classical mixing rule

A descoberta de petróleo na camada de Pré-Sal possibilita a geração de ganhos em relação à dependência energética do país, mas também grandes desafios econômicos e tecnológicos. Os custos de extração são maiores devido a vários fatores como a exigência de equipamentos de exploração que suportem elevadas pressões, altas temperaturas e grandes concentrações de gases ácidos, tais quais, dióxido de carbono (CO2) e sulfeto de hidrogênio (H2S). Uma das principais preocupações com o CO2 é evitar liberá-lo para a atmosfera durante a produção. Com a modelagem termodinâmica de dados de equilíbrio de sistemas envolvendo CO2 supercrítico e hidrocarbonetos é possível projetar equipamentos utilizados em processos de separação. A principal motivação do trabalho é o levantamento de dados de equilíbrio de fases de sistemas compostos de CO2 e hidrocarbonetos, possibilitando assim prever o comportamento dessas misturas. Os objetivos específicos são a avaliação do procedimento experimental, a estimação e predição dos parâmetros de interação binários para assim prever o comportamento de fases dos sistemas ternários envolvendo CO2 e hidrocarbonetos. Duas metodologias foram utilizadas para obtenção dos dados de equilíbrio: método estático sintético (visual) e método dinâmico analítico (recirculação das fases). Os sistemas avaliados foram: CO2 + n-hexano, CO2 + tetralina, CO2 + n-hexadecano, CO2 + n-hexano + tetralina e CO2 + tetralina + n-hexadecano à alta pressão; tetralina + n-hexadecano à baixa pressão. Para o tratamento dos dados foi utilizada equação de estado cúbica de Peng-Robinson e a regra de mistura clássica / The discovery of oil in the pre-salt layer enables the generation of earnings in relation to the energy dependence of the country, but also large economic and technological challenges. Extraction costs are higher due to various factors such as the demand for mining equipment capable of withstanding high pressures, high temperatures and high concentrations of acid gases, as such, carbon dioxide (CO2) and hydrogen sulfide (H2S). A major concern with CO2 is to avoid releasing it into the atmosphere during production. With the thermodynamic equilibrium modeling systems involving data supercritical CO2 and hydrocarbon is possible to design equipment used in separation processes. The main motivation is the data collection phase equilibrium compounds CO2 systems and hydrocarbons, thus enabling predict the behavior of these mixtures. The specific objectives are to assess the experimental procedure, the estimation and prediction of binary interaction parameters so as to predict the behavior of phases of ternary systems involving CO2 and hydrocarbons. Two methodologies were used to obtain the equilibrium data: synthetic static method (visual) and analytical dynamic method (recycling phase). The systems were evaluated: CO2 + n-hexane, CO2 + tetralin, CO2 + n-hexadecane, CO2 + n-hexane + tetralin, and CO2 + tetralin + n-hexadecane at high pressure; tetralin + n-hexadecane at low pressure. For the treatment of the data was used cubic equation of state of Peng-Robinson and the classical mixing rule

Depuis quelques années, nous assistons à une prise de conscience croissante des effets à long terme des polluants chimiques sur l'environnement et la santé humaine. Il est donc nécessaire d'étudier non seulement leurs propriétés écotoxicologiques mais également leurs propriétés physicochimiques tels que la tension de vapeur (ou volatilité) et leur solubilité dans l'eau. L'Europe, quant à elle, a introduit la réglementation REACH (Registration, Evaluation and Autorisation of CHemicals) qui est entrée en vigueur le 1 juin 2007 dont le principal objectif est une meilleure connaissance des propriétés environnementales et sanitaires des substances chimiques. De même dans l’industrie, la détermination de la tension de vapeur des corps purs est une donnée indispensable pour les opérations de purification et de séparation. Dans ce but nous avons amélioré un appareil à saturation de gaz inerte existant au laboratoire. Une fois le bon fonctionnement de l’appareil vérifié (par mesure de la tension de vapeur d’un composé de référence : le phénanthrène) nous avons étudié des n-alcanes compris entre le C30 et le C60 ainsi que 8 hydrocarbures aromatiques polycycliques dans un large domaine de température (20 à 320 °C) et de pression (10-1 Pa à 10-7 Pa). Les résultats obtenus ont été comparés avec la littérature lorsque celle-ci est disponible. La détermination des tensions de vapeur de composés inorganiques d’intérêt industriel : tétrachlorure de Zirconium (ZrCl4) et le tétrachlorure d’hafnium (HfCl4) a été également entreprise. Les résultats expérimentaux des hydrocarbures polyaromatiques nous ont permis l’amélioration d’une équation d’état cubique (dérivée de celle de Peng-Robinson) dont les paramètres sont estimés par une méthode de contribution de groupes développée par Rauzy-Coniglio. Les tensions de vapeur prédites par le modèle sont en bon accord avec les valeurs expérimentales / For a few years, we have attended an increasing importance of the long-term effects of the chemical pollutants on the environment and human health. It is thus necessary to study not only their ecotoxicological properties but also their physico-chemical properties such as the vapor pressure (or volatility) and aqueous solubility. In Addition, the introduction of the regulation REACH (Registration, Evaluation and Authorization of CHemicals) in June 2007 whose main objective is a better knowledge of the environmental and medical properties of chemical substances has increased the necessity of compound characterization. From an industrial point of view, the determination of the vapor pressure of the pure substances is an essential data in many unit operations such as purification and separation. Thus, we improved an apparatus with saturation of inert gas existing at the laboratory. Once the good performance of the apparatus checked (by measurement of the vapor pressure of a reference compound: phenanthrene) we studied N-alkanes ranging between C30 and C60 and 8 polycyclic aromatic hydrocarbons in a broad temperature range (20 to 320°C) and of pressure (10-1 Pa with 10-7 Pa). The obtained results were compared with the literature when available. In addition, determination of the vapor pressure of inorganic compounds of industrial interest : zirconium tetrachloride (ZrCl4) and the hafnium tetrachloride (HfCl4) was also undertaken. The experimental results of polyaromatic hydrocarbons have allowed us to improve a cubic equation of state (derivative of Peng-Robinson EOS) whose parameters are estimated by a method of contribution of groups developed by Rauzy-Coniglio. The predicted vapor pressures were in good agreement with the experimental values

L’objectif principal de ce travail de thèse est de développer un modèle thermodynamique de type équation d’état cubique, permettant de prédire avec un maximum de précision les propriétés thermodynamiques des corps purs (des comportements de phases aux propriétés énergétiques - enthalpie, capacité calorifique - en incluant les propriétés volumiques) et des mélanges (équilibres de phases dans les régions sub- et supercritiques, points critiques, propriétés énergétiques, densités …), y compris les plus complexes. Concernant les corps purs tout d’abord : en nous appuyant sur la connaissance acquise par les études publiées pendant près d’un siècle et demi sur les équations d’état cubiques, nous avons identifié deux leviers pour accroître la précision de ces modèles. Le premier concerne la sélection d’une fonction α optimale (cette fonction est une quantité clef apparaissant dans le terme attractif du modèle) dont le bon paramétrage permet de représenter précisément les propriétés à saturation des corps purs, telles que la pression de saturation, l’enthalpie de vaporisation et la capacité calorifique du liquide à saturation. Afin que la fonction α puisse être extrapolée au domaine des hautes températures, nous avons défini les contraintes mathématiques que celle-ci doit respecter. Le second levier est le paramètre de translation volumique, paramètre clef pour la bonne représentation des densités liquides. Ces réflexions et les études associées sont à la base du développement des modèles tc-RK et tc-PR, utilisant une fonction α extrapolable à haute température ainsi qu’un paramètre de translation volumique, garantissant une précision jusqu’alors inégalée des propriétés sub- et supercritiques des corps purs prédites par des équations d’état cubiques. Afin d’étendre les modèles tc-RK et tc-PR aux mélanges, il a été nécessaire de développer des règles de mélange appropriées pour deux paramètres de l’équation d’état des mélanges : le covolume et le paramètre attractif. Des règles de mélanges récemment proposées qui combinent équation d’état et modèle de coefficient d’activité ont été adoptées. Les valeurs optimales des paramètres universels de ces règles de mélange ont été identifiées dans le cadre de cette thèse. Une règle de mélange linéaire pour le paramètre de translation volumique du mélange a été sélectionnée ; il a été prouvé que cette règle de mélange garantit l’invariance des propriétés d’équilibre de phases et des propriétés énergétiques entre les modèles translatés et non translatés. Afin de définir le modèle de coefficient d’activité optimal à intégrer dans la nouvelle règle de mélange, une base de données de 200 systèmes binaires a été développée. Ces systèmes binaires ont été sélectionnés afin d’être représentatifs des différents types d’interactions qui peuvent exister dans les mélanges non électrolytiques. La base de données accorde une place significative aux systèmes dits associés, qui sont certainement parmi les plus difficiles à modéliser par une équation d’état. In fine, cette thèse pose toutes les bases du développement d’une équation d’état cubique des mélanges. Le choix du modèle de coefficient d’activité optimal, la détermination des paramètres d’interactions binaires des 200 systèmes de la base de données et leur prédiction constituent des suites possibles de ce travail / The main objective of this thesis work is to develop a cubic equation of state thermodynamic model able to accurately predict the thermodynamic properties of pure compounds (from phase equilibrium data to energetic properties – enthalpy, heat capacity – and volume properties) and mixtures (phase equilibria in sub- and supercritical regions, critical points, energetic properties, densities…), including the most complex ones. Starting with pure compounds: relying on the knowledge collected all through the years from Van der Waals seminal work about cubic equations of state, we identified two levers to increase cubic-model accuracy. First is the selection of the optimal α function (this function is a key quantity involved in the model attractive term) the proper parameterization of which entails an accurate representation of pure-compound saturation properties such as saturation pressure, enthalpy of vaporization, saturated-liquid heat capacity. In order to safely extrapolate an α functions to the high temperature domain, we defined the mathematical constraints that it should satisfy. The second lever is the volume translation parameter, a key parameter for an accurate description of liquid densities. These studies led to the development of the tc-PR and tc-RK models, using an α function that correctly extrapolates to the high temperature domain so as a volume translation parameter, ensuring the most accurate estimations of pure-compound sub- and supercritical property from a cubic equation of state. In order to extend the tc-PR and tc-RK models to mixtures, it was necessary to develop adequate mixing rules for both equation of state parameters: the covolume and the attractive parameter. Recently proposed mixing rules combining an equation of state and an activity coefficient model have been retained. Optimal values of the mixing rules universal parameters have been identified in the framework of this thesis. A linear mixing rule for the volume translation parameter has been selected; it has been proven that this mixing rule does not change the phase equilibrium and energetic properties when switching from a translated to an untranslated model. In order to define the optimal activity coefficient model to include in the new mixing rule, a 200 binary-system database has been developed. These binary systems have been selected to be representative of the different kinds of interactions that can exist in non-electrolytic mixtures. The database includes in particular systems containing associating compounds, which are certainly among the most difficult ones to model with an equation of state. In fine, this thesis sets all the bases for the development of a cubic equation of state for mixtures. The selection of the optimal activity-coefficient model, the estimation of binary interaction parameters for the 200 binary systems from the database and their prediction are possible continuations of this work

De nos jours, remplacer les solvants organiques utilisés traditionnellement dans l'industrie chimique par une nouvelle génération de solvants moins toxique, moins inflammable et moins polluante est un défi considérable. Les liquides ioniques, sels liquides qui satisfont ces critères, sont envisagés comme alternatives. Le but de ce travail est d'étudier le comportement des liquides ioniques en présence de composés organiques ou de gaz afin d'établir leur domaine d'applications dans le génie des procédés.Dans un premier temps, une étude chromatographique présente les interactions entre composés organiques et les liquides ioniques. Les données de rétention ont permis d'estimer la sélectivité à dilution infinie de plusieurs liquides ioniques pour différents problèmes de séparation. Un modèle de solvatation <<GC-LSER>> a été développé afin de prédire les coefficients de partage de solutés dans des liquides ioniques classiques et fonctionnalisés. Ensuite, l'étude des équilibres liquide-liquide de systèmes ternaires ont permis d'évaluer l'efficacité de trois liquides ioniques pour trois problèmes de séparation fréquemment rencontrés dans l'industrie chimique (extraction des composés aromatiques, du thiophène ou des alcools linéaires). Les valeurs des sélectivités et des coefficients de distribution élevées indiquent que les liquides ioniques étudiés peuvent remplacer les solvants traditionnels. Enfin, les performances des liquides ioniques pour la capture des gaz à effet de serre sont évaluées grâce à des mesures de solubilités du dioxyde de carbone et du protoxyde d'azote dans les liquides ioniques sous hautes pressions. Les données expérimentales ont été utilisées afin d'étendre le modèle PPR78 (Predictive 1978, Peng-Robinson equation of state) aux systèmes {CO2+ liquide ionique} / Nowadays, replacement of conventional organic solvents by a new generation of solvents less toxic, less flammable and less polluting is a major challenge for the chemical industry. Ionic liquids have been widely promoted as interesting substitutes for traditional solvents. The aim of this work is to study the behavior of ionic liquids with organic compounds or gases in order to determine their range of applications in process engineering.First, interactions between organic compounds and ionic liquids are studied using inverse gas chromatography. The activity coefficients at infinite dilution are used to calculate capacity and selectivity of different ionic liquids for different separation problems. A solvation model <<GC-LSER>> is proposed in order to estimate the gas-to-ionic liquid partition coefficients in alkyl or functionalized ionic liquids. Then, liquid-liquid equilibria measurements of ternary systems were carried out in order to evaluate the efficiency of three ionic liquids for three separation problems frequently encountered in chemical industry (extraction of aromatic compounds, thiophene or linear alcohols). The high values of distribution coefficients and selectivities indicate that the investigated ionic liquids could replace the traditional solvents. Finally, the performance of ionic liquids for greenhouse gases capture was examinated through solubility measurements of carbon dioxide and nitrous oxide in ionic liquids at high pressure. The experimental data is used in order to extend the model PPR78 (Predictive 1978, Peng-Robinson equation of state) to systems containing {CO2+ ionic liquid}