Η παρούσα διδακτορική διατριβή αποτελείται από δύο ξεχωριστές ενότητες οι οποίες έχουν σαν στόχο τη μελέτη τροποποιημένων πολυμερικών μεμβρανών για χρήση σε κυψελίδες καυσίμου αγωγής πρωτονίων και σε εφαρμογές διαχωρισμού αερίων. Στην πρώτη ενότητα έγινε εκτίμηση του μοριακού προσανατολισμού μονοαξονικά εφελκυσμένων πολυμερικών μεμβρανών Nafion-115 με τη βοήθεια πολωμένων φασμάτων UV-Raman. Πειράματα δυναμικής μηχανικής ανάλυσης επαλήθευσαν τις προσδοκίες για βελτίωση των μηχανικών ιδιοτήτων του πολυμερικού ηλεκτρολύτη κατά μήκος της διεύθυνσης εφελκυσμού. Η θερμική ανάλυση των δειγμάτων με τις τεχνικές της διαφορικής θερμιδομετρίας σάρωσης και της θερμοσταθμικής ανάλυσης δεν έδειξε κάποια ιδιαίτερη διαφοροποίηση μεταξύ εφελκυσμένων και μη δοκιμίων Nafion-115, πέραν της βελτίωσης της ικανότητας των τανυσμένων μεμβρανών να συγκρατούν το όποιο νερό υπάρχει στο ιονομερές. Μικρή ήταν η αύξηση της ιοντικής αγωγιμότητας που παρατηρήθηκε στα τανυσμένα δείγματα κατά μήκος της διεύθυνσης εφελκυσμού. Η προσπάθεια τροποποίησης του Nafion® με διαξονικό εφελκυσμό είχε σαν αποτέλεσμα τη λήψη λεπτών πολυμερικών ηλεκτρολυτικών μεμβρανών με αποτελεσματικότερες ιδιότητες στην τάση διέλευσης της μεθανόλης, σε σχέση με τις μη τροποποιημένες μεμβράνες. Επιπρόσθετα, με τον ελεγχόμενο διαξονικό και σταθερού πλάτους μονοαξονικό εφελκυσμό κατέστη δυνατό να επιτευχθεί η εξισορρόπηση των ποσοστών διαστολής κατά το μήκος και πλάτος της επιφάνειας του Nafion, μετά τον εμποτισμό του με νερό. Όσον αφορά στην τροποποίηση του Nafion με εναπόθεση στοιβάδας αγώγιμου πολυμερούς πολυανιλίνης (PAni) ή πολυπυρρόλης (PPy) με ενσωματωμένα αντισταθμιστικά ιόντα SO42- ή Nafion-, η φασματοσκοπική μελέτη, μέσω ATR-FTIR, σε συνδυασμό με τις μικροφωτογραφίες SEM που ελήφθησαν, οδήγησαν στα εξής συμπεράσματα: Για τις σύνθετες μεμβράνες Nafion/PAni που παρασκευάστηκαν με την τεχνική της διάχυσης, από τη μία ελήφθησαν δείγματα με ικανοποιητική συνάφεια μεταξύ του κυρίως όγκου της πολυμερικής μεμβράνης Nafion και της PAni, από την άλλη όμως, υπάρχει και κάποιο ποσοστό μονομερούς ανιλίνης (Ani) που εγκλωβίζεται στο εσωτερικό του Nafion, και μάλιστα σε σημαντικό βαθμό, που εξαρτάται από το χρόνο σύνθεσης. Αντίθετα, οι αντίστοιχες μελέτες στις μεμβράνες Nafion/PPy δε φανερώνουν την ύπαρξη διείσδυσης της PPy ή του μονομερούς στην κύρια μάζα του Nafion, ή τουλάχιστον όχι σε τέτοιο βαθμό που να μπορεί να ανιχνευθεί μέσω της τεχνικής που χρησιμοποιήθηκε. Ιδιαίτερο είναι το ενδιαφέρον που προκύπτει από τις φασματοσκοπικές μετρήσεις στην πλευρά του σύνθετου πολυμερούς όπου εναποτίθετο το πολυμερισμένο αγώγιμο υλικό, καθώς με το χρόνο σύνθεσης παρατηρούνται μετατοπίσεις κορυφών του Nafion προς χαμηλότερες συχνότητες, υποδεικνύοντας ενδεχόμενη αλληλεπίδραση με το αγώγιμο πολυμερές. Στη δεύτερη ενότητα μελετήθηκαν οι σύνθετες (ή “mixed matrix”) πολυμερικές μεμβράνες πολυσουλφόνης (PSF) με ενσωματωμένες φυλλώδεις αργυλοφωσφορικές νανονιφάδες τύπου AlPO. Αρχικά πραγματοποιήθηκε η σύνθεση των νανονιφάδων AlPO. Με στόχο τη βελτίωση της συμβατότητάς τους με την πολυμερική μήτρα έγινε παρεμβόλιση με κατάλληλη επιφανειοδραστική ουσία και χαρακτηρισμός με XRD που έδειξε τη διεύρυνση της απόστασης μεταξύ των διαδοχικών στρωμάτων του κρυστάλλου από 9Å σε 33Å περίπου. Στη συνέχεια παρασκευάσθηκαν οι σύνθετες μεμβράνες με διαφορετικές συγκεντρώσεις της ανόργανης φάσης, με τη μέθοδο του film casting. Με βάση τις εικόνες SEM οι νανονιφάδες φαίνεται να έχουν ικανοποιητική διασπορά στη μάζα της πολυσουλφόνης, ενώ τα φάσματα XRD δείχνουν πως η ενσωμάτωση των παρεμβολισμένων νανονιφάδων στην πολυμερική μήτρα δεν επέφερε κάποια σημαντική αλλαγή στη δομή τους. Οι νανονιφάδες, ακόμα και σε μικρές συγκεντρώσεις, βελτιώνουν σε σημαντικό βαθμό τη διαχωριστική ικανότητα των αμιγώς πολυμερικών μεμβρανών για τα ζεύγη αερίων H2/N2 και Η2/CH4 όχι όμως και για το ζεύγος Η2/CO2. Αντίθετα, η αύξηση του ποσοστού των νανονιφάδων AlPO οδηγεί σε μείωση της διαπερατότητας του H2. Oι σύνθετες μεμβράνες PSF/AlPO δείχνουν μια μικρή βελτίωση του μέτρου ελαστικότητας αποθηκευόμενης ενέργειας σε σχέση με τις πολυμερικές μεμβράνες PSF, εμφανίζουν επίσης ελαφρώς μειωμένη θερμοκρασία υαλώδους μετάβασης και, κατά τη θέρμανσή τους, ακολουθούν τρία στάδια απώλειας μάζας λόγω αποσύνθεσης της επιφανειοδραστικής ουσίας σε συνδυασμό με απώλεια φυσικά και χημικά ροφημένου νερού. / The present thesis consists of two separate parts which focus on the study of modified polymer membranes for use in fuel cells applications and gas separation processes. In the first part, the molecular orientation of uniaxially drawn Nafion-115 membranes was estimated utilizing polarized UV-Raman spectra. Dynamic mechanical analysis revealed the enhanced strength of the drawn samples along the draw axis. Thermal analysis, carried out via differential scanning calorimetry, and thermogravimetric analysis did not show any difference between drawn and undrawn specimens, except from a slight enhanced capability of the drawn membranes to water content retain. Proton conductivity is slightly enhanced along the stretching direction, as well. The attempts for biaxial stretching of Nafion® had as a result the production of very thin polymer electrolyte membranes with lower permeability to methanol than the commercial one. In addition, with biaxial and constant width uniaxial stretching, the swelling of Nafion along and across its surface can be controlled. The process of modifying Nafion by embedding conducting polymer layers of polypyrrole or polyaniline with SO42- or Nafion- incorporated into the film as counter-ions is studied via ATR-FTIR spectroscopy in combination with SEM microphotographs. Nafion/PAni composite membranes synthesized by the diffusion method showed very good adherence between Nafion and PAni layers but it seems that there is some Ani monomer still remaining inside the bulk structure of Nafion, depending on the time of synthesis. In contrast, the corresponding studies on Nafion/PPy membranes show that there is no penetration of PPy or Py inside Nafion, at least not to the extent that it could be traced using ATR-FTIR spectroscopy. The spectroscopic measurements from the conducting polymer side show red-shifts of absorption bands of Nafion revealing possible specific interactions with the conducting polymer. In the second part, composite (or mixed matrix) polymeric membranes with dispersed aluminophosphate nanoflakes were studied. At the beginning AlPO nanoflakes were synthesized. To enhance the compatibility with the polymer matrix conventional AlPO nanoflakes were intercalated using suitable surfactant. XRD characterization showed a further individual layers` separation since the distance between them is increased from 9Å to 33Å. Subsequently, mixed matrix membranes with different nanoflakes loading were synthesized, using film casting method. Based on SEM images nanoflakes seem to be well dispersed in the mass of polysulfone, while XRD graphs implied that the incorporation of intercalated nanoflakes into the polymer matrix did not affect their structural characteristics. Nanoflakes incorporation, even at very low concentrations, improves the H2/N2 and H2/CH4 selectivity and deteriorates the H2/CO2 selectivity compared with the pure polymer. On the other hand, the higher the percentage of the AlPO flakes, the more pronounced the decrease in hydrogen permeability. PSF/AlPO membranes exhibit improved storage modulus, appear to have slightly lower glass transition temperature compared with PSF membranes and during their heating, follow a three steps mass loss due to the surfactant decomposition and the loss of physically and chemically absorbed water.

O presente trabalho apresenta um estudo associado à separação de gás para escoamento gás-líquido em um duto anular inclinado. Esse tipo de escoamento e geometria são encontrados em separadores de gás do tipo shroud invertido na indústria de petróleo quando utilizadas técnicas de bombeamento para a exploração de poços. A presença de gás livre a montante da bomba é uma das maiores limitações dos sistemas de bombeamento, por acarretar cavitação e falhas dinâmicas nos equipamentos. O presente estudo tem por objetivo garantir a separação total de gás livre a montante da bomba através da proposição de um separador do tipo shroud invertido em tubulação inclinada para aplicação na exploração de petróleo em poços direcionais. Um estudo experimental com ar e água como fluidos de trabalho a pressão quase atmosférica foi desenvolvido visando a compreensão da fenomenologia do separador shroud invertido. Foram observados escoamentos em duto anular do tipo: bifásico gás-líquido ascendente, monofásico em canal livre e bifásico gás-líquido descendente devido ao fenômeno de aeração; foram coletados também dados de eficiência de separação em função do ângulo de inclinação, vazão do líquido e queda de pressão entre o shroud e a saída do tubo de produção. Encontrou-se uma variável de extrema importância no fenômeno de separação até agora não reportada na literatura: o nível do anular interno do shroud (NAI). Um modelo fenomenológico que prevê a separação total do gás foi desenvolvido a partir da interpretação dos fenômenos físicos observados experimentalmente. Uma correlação inédita para a modelagem do fenômeno de dissipação de energia cinética turbulenta vinculado à separação do gás é proposta. O modelo foi validado qualitativamente com dados da literatura e ajustado com os dados coletados neste trabalho, mostrando boa concordância. / This paper presents a study associated with gas separation in an inclined gas-liquid annular-duct flow. This type of flow and geometry are found in shroud-inverted gas separators applied to petroleum industries when using pumping technique for oil production. High void fraction at the pump suction of is one of the most important limitations of the SCP technique, causing cavitation and dynamics failures in the equipment. The present study aims to provide a solution for the total gas separation through the use of an innovative inclined inverted-shroud separator for directional wells. An experimental study, where air and water at near atmospheric pressure constituted the working fluids, was carried out to understand the phenomenology of the inclined inverted-shroud separator. Different annular-duct flows were observed: upward gas-liquid flow, single-phase open channel flow, downward gas-liquid flow due to the phenomenon of aeration; also new data of separation efficiency were collected as a function of inclination angle, liquid flow rate and pressure drop between the shroud and production pipe outlet. One of the most significant findings is that the liquid level of the inner annular channel (NAI) of the shroud is a very important variable in the phenomenon of separation; so far this was not reported in the literature. Based on the observations, a phenomenological model that predicts total gas separation is proposed. A new correlation for the modeling of the dissipation of turbulent kinetic energy associated with the gas separation is presented. The model was qualitatively compared with available data from the literature and quantitatively adjusted against the new experimental data obtained in this work, and the agreement was quite good.

Propõe-se o estudo do separador gravitacional de fundo de poço do tipo shroud invertido para poços direcionais e horizontais. A geometria inovadora é observada pela inclinação imposta, solução que transforma um escoamento vertical descendente, veloz e caótico, num escoamento inclinado e segregado em canal livre. Com a inclinação, minimizasse a incorporação de gás, no impacto do escoamento em superfície livre contra a interface de líquido formada pelo nível do anular interno (NAI), e a segregação é incrementada devido ao gradiente de velocidades e ao aparecimento da componente da gravidade na direção radial do poço de petróleo. O trabalho experimental tem como uma de suas metas o levantamento da eficiência de separação em função das vazões de líquido e gás, do ângulo de inclinação e o grau de interferência do escoamento no duto anular formado entre o separador e a parede do poço de petróleo, chamado neste trabalho de anular externo. Foi feito um trabalho de semelhança dimensional e foram detectados os números adimensionais pertinentes ao problema. Constatou-se que a vazão de gás e o escoamento no anular externo não interferem na eficiência de separação. Além disso, foi realizado um trabalho de caracterização dos padrões do escoamento gás-líquido em duto anular, através de visualização e análise no domínio do tempo e da frequência do sinal dinâmico da queda de pressão. Também são propostos dois modelos matemáticos, um modelo fenomenológico baseado em princípios físicos fundamentais, que foi capaz de prever com eficácia a região de máxima eficiência do separador shroud invertido, e um modelo numérico, que reproduziu a fenomenologia do processo de separação do gás. / This research project proposes the study of the inverted-shroud gravitational gas separator for directional and horizontal wells. The innovative geometry is observed by the inclination that transforms a vertical, fast and chaotic downward flow into an inclined and segregated free channel flow. Due to inclination, the incorporation of gas at the internal gasliquid interface (NAI) is minimized; the segregation is increased due to the velocity gradient and the gravitational term that arises in the radial direction of the oil well. One of the aims of the experimental work is the obtaining of new data of gas separation efficiency as a function of the flow of liquid and gas, inclination angle and the evaluation of the degree of interference of the external annular duct flow. A dimensional analysis was undertaken to identify the relevant dimensionless numbers. It was found that the gas flow and the flow pattern in the external annular duct do not interfere in the separation efficiency. A flow pattern characterization was carried out through visualization and time and frequency domain analysis of differential pressure signature signal. Two mathematical models are proposed, a phenomenological model based on fundamental physical principles, which was able to predict with good accuracy the region of maximum separation efficiency, and a numerical model, which reproduced the phenomenology of the gas separation process.

To meet the continuously rising demand for natural resources and high-value compounds, the development of new and more efficient separation technologies is important from both an economic and environmental point of view. Moreover, the detailed knowledge of adsorption phenomena can be beneficial for the development of task-specific adsorbents for gas separation processes. However, new or supplementary measurement techniques are needed to broaden the understanding of the underlying molecular mechanisms and to characterize promising materials with a fast and reliable method. Raman spectroscopy holds the potential to advance the state-of-the-art in thermophysical property research for CCS technologies in multiple ways. It can not only be utilized for fundamental research on adsorption on quasi non-porous materials due to the possibility to monitor the composition of fluid mixtures but also for the characterization of newly developed porous adsorbents. In this context, Raman spectroscopy was explored in this work to characterize the sorption capacity of translucent porous materials and to investigate the underlying mechanisms that govern sorption processes.:1 Introduction 2 Motivation 3 Experimental Background 4 Adsorption on Quasi Non-Porous Materials 5 Adsorption on Translucent Porous Materials 6 Gas Solubility in Liquids 7 Conclusion and Outlook 8 References Appendix: A Determined Peak Intensities for Adsorption Measurements B Determined Peak Intensities for Solubility Measurements C Results for Absorption Measurements D Results for Solubility Measurements E Propagation of Error / Um den ständig steigenden Bedarf an natürlichen Ressourcen und hochwertigen Verbindungen zu decken, ist die Entwicklung neuer und effizienterer Trenntechnologien sowohl aus wirtschaftlicher als auch aus ökologischer Sicht wichtig. Darüber hinaus kann die detaillierte Kenntnis von Adsorptionsphänomenen für die Entwicklung aufgabenspezifischer Adsorbentien für Gastrennverfahren von Nutzen sein. Es werden jedoch neue oder ergänzende Messverfahren benötigt, um das Verständnis der zugrunde liegenden molekularen Mechanismen zu erweitern und vielversprechende Materialien mit einer schnellen und zuverlässigen Methode zu charakterisieren. Die Raman Spektroskopie hat das Potenzial, den aktuellen Stand der Technik bei der Erforschung thermophysikalischer Eigenschaften für CCS-Technologien in mehrfacher Hinsicht zu verbessern. Sie kann nicht nur für die Grundlagenforschung zur Adsorption an quasi nicht-porösen Materialien genutzt werden, da mit ihr Zusammensetzung von Fluidgemischen bestimmt werden kann, sondern auch für die Charakterisierung neu entwickelter poröser Adsorptionsmittel. In diesem Kontext wurde die Raman-Spektroskopie in dieser Arbeit eingesetzt, um die Sorptionskapazität von transluzenten porösen Materialien zu charakterisieren und die zugrundeliegenden Mechanismen zu untersuchen, welche die Sorptionsprozesse steuern.:1 Introduction 2 Motivation 3 Experimental Background 4 Adsorption on Quasi Non-Porous Materials 5 Adsorption on Translucent Porous Materials 6 Gas Solubility in Liquids 7 Conclusion and Outlook 8 References Appendix: A Determined Peak Intensities for Adsorption Measurements B Determined Peak Intensities for Solubility Measurements C Results for Absorption Measurements D Results for Solubility Measurements E Propagation of Error

Au cours des dernières décennies, les technologies membranaires ont largement contribué à l’amélioration des procédés de séparation à l’échelle industrielle grâce à de nombreux avantages, tels que la sélectivité de la séparation élevée, la possibilité de travailler avec des composés thermolabiles et la faible demande en énergie, ainsi que la possibilité de combiner les technologies membranaires avec d'autres procédés de séparation. Le procédé de pervaporation est une technique de séparation membranaire importante utilisée pour séparer les mélanges liquides binaires ou multicomposants, y compris les solvants à point d’ébullition proche, les mélanges azéotropes et les isomères. Il s’agit du transfert sélectif de matière à travers une membrane dense. Au cours de cette opération, le perméat sous forme vapeur est condensé sur une paroi froide, mais, contrairement à la distillation, seule une faible partie de la charge subit ce changement d’état. Les membranes utilisées dans la pervaporation doivent posséder une forte sélectivité, une stabilité chimique et une résistance mécanique à haute température élevées. La sélectivité et les propriétés de transport de la membrane déterminent l'efficacité globale du processus de séparation. La caractérisation approfondie des membranes est cruciale pour bien comprendre l’influence de la structure de la membrane et des conditions de préparation de la membrane sur les caractéristiques d’équilibre, de séparation et de transport des membranes étudiées, en vue de développer de nouveaux matériaux polymères efficaces. Les nombreuses recherches ont également été menées sur le développement des membranes avec de liquides ioniques (LIs) afin de personnaliser les propriétés de séparation des membranes utilisées dans la séparation des liquides par pervaporation, la séparation des gaz et la séparation des ions métalliques ainsi que les membranes conductrices dans les piles à combustible. Les LIs sont caractérisés par une bonne stabilité thermique, une conductivité ionique élevée, une pression de vapeur négligeable et un point de fusion assez bas. En raison de leurs nombreuses propriétés uniques, les membranes polymères contenant des LIs possèdent une large gamme d'avantages, comme de meilleures propriétés de séparation que les membranes polymères classiques. Ce fait est lié à une diffusion moléculaire beaucoup plus élevée dans un liquide ionique que dans des polymères. Par conséquent, l'utilisation de membranes à base de polymères et LIs dans les processus de séparation permettrait une sélectivité de séparation élevée et des flux plus importants. La structure et les propriétés physicochimiques des LIs peuvent être ciblées en fonction de l’application afin d'obtenir un matériau polymère approprié. En revanche, même si l’application de membranes hybrides à base de polymères et LIs suscite un intérêt croissant, leur utilisation dans les procédés de séparation reste limitée en raison des pertes de LI non lié. Cette thèse de doctorat en co-tutelle est réalisée entre la Faculté de Chimie de l'Université Nicolaus Copernicus (NCU) à Toruń (Pologne) et le Laboratoire Polymères, Biopolymères, Surfaces UMR 6270 CNRS de l’Université de Rouen Normandie (France). L’objectif principal de la thèse est d’élaborer de nouvelles membranes denses à base de poly (alcool vinylique) (PVA) et d’acétate-propionate de cellulose (CAP) et de divers LIs réactifs et polymérisables ceci afin d’obtenir un système polymère-liquide ionique dans lequel le LI est stabilisé par liaison covalente avec les chaînes macromoléculaires du polymère. L'étude des propriétés physicochimiques et d'équilibre des membranes a été effectuée ainsi que l’analyse de leurs propriétés de transport. De plus, les membranes sélectionnées ont été testées dans un processus de pervaporation en contact avec le mélange eau-propane-2-ol. / In the last decades, membrane separation has played an important role in many industrial processes thanks to its versatility, low energy consumption, high performances of membranes, as well as a possibility of combining membrane technologies with other separation processes. Membrane technologies gave a great contribution to the improvement of separation processes in the industrial scale thanks to a number of advantages, such as the high selectivity of the separation, the opportunity to work with thermolabile compounds, and low energy demand. Pervaporation process is an important membrane separation technique used to separate binary or multicomponent liquid mixtures including close boiling solvents, azeotrope mixtures, and isomers. During pervaporation, feed components are in the direct contact with one side of the lyophilic membrane, while the selected components are preferentially transported across the membrane to the permeate side. Membranes used in pervaporation must be characterized by high selectivity, chemical stability, and mechanical strength at high temperatures. Selectivity and transport properties of the membrane determine the overall efficiency of the separation process. The comprehensive characterization of membranes is the crucial approach and can lead to broaden the knowledge about the influence of the membrane structure and membrane preparation conditions on the equilibrium, separation, and transport characteristics of the studied membranes, in order to develop new polymer materials with the expected efficiency of the separation process. Research has been also focused on the development of the membranes filled with ILs in order to tailor the separation properties of the developed membranes used in liquid separation by pervaporation, gas separation, and separation of metal ions as well as the conducting barriers in fuel cells. ILs are characterized by good thermal stability, high ionic conductivity, negligible vapor pressure, and low melting point. Due to their numerous unique properties, polymer membranes containing ILs (polymer-ILs) possess wide range of advantages, like better separation properties than the classical polymer membranes. This fact is related with much higher molecular diffusion in ionic liquid than in polymers. Therefore, the use of polymer-ILs in separation processes would result in superior separation behavior and higher fluxes. Morphology and physicochemical properties of ILs can be “tailored” depending on the separated system in order to obtain a suitable polymer material for a given separation process without preparation of a chemically new membrane. Even though there is a growing interest in the application of polymer membranes filled with ILs, the polymer-ILs based separation processes are limited due to the losses of the unbound ionic liquid in the course of the exploitation. The PhD is realized in the frame of "co-tutelle" system between the Faculty of Chemistry at the Nicolaus Copernicus University (NCU) in Toruń, Poland (Membranes and Membrane Separation Processes Research Group) and the University of Rouen Normandy, France (Barrier Polymer Materials and Membranes (MPBM) Research Group of the Laboratory of Polymers, Biopolymers, Surfaces (PBS)). The main aim of the present PhD thesis is to elaborate novel dense membranes based on poly(vinyl alcohol) (PVA) and cellulose acetate propionate (CAP) filled with various reactive and polymerizable ILs in order to obtain the polymer-ionic liquid system in which ionic liquids are linked inside the polymer structure. The investigation of physicochemical characteristics and study of the equilibrium, barrier, and transport properties of the obtained membranes was carried out. Furthermore, the selected membranes were tested in pervaporation process in contact with water-propan-2-ol mixture, water and gas permeation measurements.

Spreading of mixtures of oil with suitable silica particles onto a water surface leads to the formation of composite layers in which particles protrude at the top and at the bottom from the oil. Solidification of the oil and removal of the particles give rise to porous membranes. Pore widths and membrane thicknesses depend on particle sizes and usually are in the range of 70 – 80% of their diameters. Often freely suspended porous membranes are too fragile to operate them in pressure filtration without supportive structure. To improve mechanical stability of porous membranes, a mixture of silica particles with an oil is spread onto a nonwoven fibrous support that was drenched with water. Solidification of the oil and removal of particles yields porous membrane attached to the fibers of the support. Due to inhomogeneous surface of the fabric, the membranes that are attached to it are corrugated. To obtain flat supportive structures, glass beads with 75 μm in diameter are spread onto the water surface with the oil. Solidification of the oil and then removal of particles gives rise to porous membranes with pore diameters in micrometer range. Another concept of improvement of mechanical stability is the preparation of asymmetric membranes via spreading of a mixture of two sorts of particles with opposite surface properties with the oil onto the water surface. After solidification of the oil and removal of particles, membranes with pores width in the range from 30 – 50 nm are obtained. Slow removal of silica particles from composite monolayer that floats on the water surface gives rise to silica rings in intermediate stages of removal. Mixed matrix membranes with embedded carbon molecular sieves are prepared in a similar process as detailed above by using carbon particles instead of silica. Carbon molecular sieves protrude at the top and bottom from the polymeric matrix. Theoretical prediction of permeability and selectivity through these membranes are much higher than in membranes where particles are smaller than the membrane thickness. / Spreitet man Mischungen eines Öls mit geeigneten Kieselgelpartikeln auf eine Wasseroberfläche, führt dies zur Bildung gemischter Schichten, in denen die Partikel auf der Ober- und Unterseite aus dem Öl herausragen. Härtet man das Öl aus und entfernt die Partikel, erhält man poröse Membranen mit einheitlichen Poren. Dabei hängen die Porenweiten und Membrandicken von der Partikelgröße ab und betragen üblicherweise 70 – 80 % von deren Durchmesser. Oft sind freitragende poröse Membranen zu zerbrechlich um mit ihnen Druckfiltration ohne Stützstruktur durchzuführen. Um die mechanische Stabilität von porösen Membranen zu erhöhen spreitet man eine Mischung aus Kieselgelpartikeln und einem Öl auf einem Vliesstoff, der mit Wasser getränkt ist. Das Aushärten des Öls und die Entfernung der Partikel führt zu einer porösen Membran, die an die Fasern der Stützstruktur angeheftet ist. Durch die inhomogene Oberfläche des Vliesgewebes sind die daran angehefteten Membranen gewellt. Um eine ebene Stützstruktur zu erhalten, werden Mischungen aus dem Öl und Glaskugeln mit einem Durchmesser von 75 μm verwendet. Das Aushärten des Öls und die Entfernung der Partikel führt zu ebenen porösen Membranen mit Porendurchmessern im Mikrometerbereich. Ein weiteres Konzept, um die mechanische Stabilität zu erhöhen, ist die Herstellung asymmetrischer Membranen mit Hilfe des Spreitens einer Mischung zweier Partikelsorten mit unterschiedlichen Oberflächeneigenschaften mit dem Öl auf die Wasseroberfläche. Nach dem Aushärten des Öls und der Entfernung der Partikel erhält man eine asymmetrische Membran mit kleinen Porenweiten an der Oberseite und großen Porenweiten an der Unterseite. Durch langsames Entfernen der Kieselgelpartikel aus der gemischten Schicht, die auf der Wasseroberfläche schwimmt, kann man in einem Zwischenstadium Kieselgelringe erhalten. Kompositmembranen (mixed matrix membranes) mit eingebetteten Kohlenstoffmolekularsieben werden in einem gleichen Prozess wie oben beschrieben hergestellt, indem man Kohlenstoffpartikel anstatt der Kieselgelpartikel verwendet. Die Kohlenstoffmolekularsiebe ragen auf der Ober- und Unterseite aus der Polymermatrix heraus. Die theoretisch vorhersagten Durchlässigkeiten und Selektivitäten solcher Membranen sind wesentlich höher als bei Membranen, in denen die Partikel kleiner als der Membrandicke sind.

Für die hochselektive technische Trennung von Stoffen hält die Natur eine optimale Lösung namens Zeolithe bereit. In dieser Arbeit wurden Zeolith 4A in Form von Partikeln und wenig permeables Polymer in einer Membran kombiniert. Die Partikel lagen dabei in einer Monolage vor und wurden lediglich seitlich vom Polymer eingefasst, sodass sie beide Oberflächen der Polymerschicht durchbrachen. Diese Einbettung zu so genannten Zeolithkompositmembranen erlaubt einen Stofftransport ausschließlich durch die hochselektiven Zeolithpartikel. Die Herstellung und Charakterisierung der Zeolithkompositmembranen stehen im Mittelpunkt der vorliegenden Arbeit. Für die Membranherstellung kam das Prinzip der partikelassistierten Benetzung einer Wasseroberfläche zum Einsatz. Hierfür wurden die Zeolithpartikel beschichtet und anschließend das unverändert zugängliche Porensystem mittels Thermogravimetrie in Wasseradsorptions-Desorptionsmessungen nachgewiesen. Aus beschichteten Partikeln und passendem Monomer konnten schichtdickenoptimierte Zeolithkompositmembranen hergestellt werden. Es wurde eine Permeabilität P für Wasserdampf von 49 barrer festgestellt, während die Gase Stickstoff und Sauerstoff keinen Transportnachweis zuließen (P < 0,03 barrer). Daraus ergeben sich Selektivitäten von über 1600. Die Durchlässigkeit für Wasser beweist ein offenes Porensystem, die Impermeabilität für Stickstoff und Sauerstoff deutet auf eine sehr geringe Defektdichte hin, was beste Voraussetzungen für Trennmembranen darstellt. Das Herstellungsprinzip soll als Vorlage für die Präparation maßgeschneiderter Kompositmembranen mit wählbarer Porengröße dienen. Vergleiche zu konventionellen Zeolithmembranen belegen, dass die partikelassistierte Benetzung die Methode der Wahl ist, partikelförmiges hochselektives Material optimal einzubetten, ohne die begehrten Permeationseigenschaften zu beeinträchtigen. / An optimal material for highly selective separation processes can be found in zeolites. We prepared composite membranes composed of zeolite 4A particles and a polymer of low permeability. The particles formed a dense monolayer which were embedded into the polymer sheet in such a way that each particle prenetrates both the top and the bottom surface of the sheet. Only this embedding offffers a transport through the highly selective particles exclusively. This work focusses on these so called zeolite composite membranes, on their preparation and characterization. The preparation of the membranes was done via particle assisted wetting on a water surface. Therefore the zeolite particles were coated by a suitable silane agent and a blocking of the pore openings by the coating process was disproved by water adsorption-desorption measurements via TGA. Using the coated particles and a suitable monomer composite membranes could be formed and the optimum thickness was found. The membranes were permeable for water vapor (permeability P = 49 barrer), but impermeable for nitrogen and oxygene (P < 0,03 barrer (detection limit)). This results in a selectivity of above 1600. The permeability for water indicates that the molecules are transported through the zeolite channels. The impermeability for nitrogene and oxygene indicates a very low amount of defects. Furthermore the composite nature of the membrane reduces brittleness thus rendering it a promising candidate for separation technology with tailoring the pore size.

Microporous membranes act as selective barriers and play an important role in industrial gas separation and water purification. The permeability of such membranes is inversely proportional to their thickness. Synthetic two-dimensional materials (2DMs), with a thickness of one to a few atoms or monomer-units are ideal candidates for developing separation membranes. In this Progress Report, we present groundbreaking advances in the design, synthesis, processing, and application of 2DMs for gas and ion separations, as well as water desalination. After the introduction in Section 1, this report describes the syntheses, structures, and mechanical properties of 2DMs in Section 2. In Section 3, we will discuss the established methods for processing 2DMs into selective permeation membranes and address the separation mechanism and their performances. Finally, current challenges and emerging research directions, which need to be addressed for developing next generation separation membranes, are summarized in the Conclusion and Perspective.

Gegenstand dieser Arbeit ist es, die Temperaturbeständigkeit von bikontinuierlichen Kompositmembranen bestehend aus Zeolith 4A und Visiomer HEMATMDI zu überprüfen und das Verhalten ihrer Permeanz im Verlauf der Temperaturerhöhung zu untersuchen. Weiterhin wird ihre Verwendbarkeit für technisch und industriell relevante Prozesse der Gastrocknung nachgewiesen. Zunächst wird thermogravimetrisch untersucht, bei welcher Temperatur Zersetzungserscheinungen an der polymeren Komponente auftreten. Anschließend wird thermogravimetrisch der Wassergehalt von Zeolith 4A im Bereich dieser Temperatur bestimmt. Hierauf folgen Permeationsmessungen mit Sauerstoff und Stickstoff an der bikontinuierlichen Kompositmembran. Die Temperatur wird hierbei schrittweise bis knapp unter die Zersetzungstemperatur des Polymers erhöht. Die Eignung der Membranen zur Gastrocknung wird exemplarisch an der Trocknung von Erdgas gezeigt. Es werden die Permeanzen für Wasserdampf und Methan als Hauptbestandteil von Erdgas mittels Einzelgasmessungen experimentell bestimmt. Aus diesen Permeanzen errechnet sich die ideale Selektivität der bikontinuierlichen Kompositmembran von Wasserdampf gegenüber Methan. Mit ihrer Hilfe lässt sich die Eignung der Membran zur Trocknung von Erdgas abschätzen. / The aim of this work is to study the temperature resistance of bicontinuous composite membranes, composed zeolite 4A and Visiomer HEMATMDI, and their permeances with rising temperatures. Furthermore their suitability for gas drying is investigated.

[pt] A implementação de medidas que reduzam as emissões de gases de efeito estufa ganha importância no cenário atual. Um importante método para captura de CO2 consiste nos processos de separação por membranas. Visando melhorar a eficiência seletiva na separação de gases, este trabalho estudou a síntese de membranas poliméricas de matrizes mistas a fim de aumentar os valores de permeabilidade, utilizando líquidos iônicos em sua estrutura, que apresentam elevada solubilidade de CO2 e seletividade. A síntese do líquido iônico foi realizada a partir do cátion imidazólico e do ânion NTf2(-) , em reações de 3 etapas. Os filmes poliméricos de matrizes mistas foram sintetizados por diferentes tipos de polímeros comerciais, PEBAX 1657, PEBAX2533 e PU 1185A10; com concentrações de 0 por cento, 20 por cento e 60 por cento (m/m) do líquido iônico. A técnica de ressonância magnética nuclear (RMN) de (1)H e (13)C foi utilizada para validar a composição do líquido iônico. As caracterizações de membranas compósitas se deram pelas técnicas de microscopia eletrônica de varredura (MEV), análise termogravimétrica (TGA) e espectroscopia de infravermelho com transformada de Fourier (FTIR). Na presença do líquido iônico, a seletividade relativa de CO2/N2 apresentou um aumento considerável para as membranas de PU e PEBAX2533, enquanto a permeabilidade de CO2 aumentou nas membranas de PU e PEBAX1657. / [en] The measures to reduce greenhouse gas emissions, gains more importance in the current scenario. Processes involving membrane separation are an important method for CO2 capture which are widely used. In order to improve the selective efficient in the gas separation this paper studies the development and synthesis of composite polymeric membranes that will be able to increase the permeability using ionic liquids in your structure, which have high CO2 solubility and selectivity. The ionic liquid synthesis was obtained using imidazolium cation and the NTf2(-) anion, on 3 steps reactions. The composite polymeric membranes were synthesized by different types of commercial polymers, PEBAX1657, PEBAX2533 and PU 1185A10; with 0 percent, 20 percent and 60 percent (wt.) concentrations of ionic liquid. The nuclear magnetic resonance (NMR) technique for 1H and 13C was used to validate the ionic liquid structure. The composite membrane characterizations were obtained by those techniques: scanning electron microscope (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR). In the presence of ionic liquid, the selectivity of CO2/N2 increased for the PU and PEBAX2533 membranes, and the permeability of CO2 increased for the PU and PEBAX1657 membranes.