"Catalytic growth of Carbon Nanotubes (CNT) provides important advantages of controlling their diameters and possibly chirality. Our work involved growing CNT on model and supported catalyst by catalytic decomposition of carbon source such as benzene, methane and propylene. On supported catalyst, iron nitrate was deposited on alumina and reduced to form metallic iron clusters. These were reacted at 700 - 950 C under varying benzene concentrations. Multi Walled CNT (MWNT) grew below 800 C and Single Wall CNT (SWNT) are observed at 850 C and above as confirmed by TEM and Raman. Model catalysts were studied by producing CNT from ferrocene which acted as the carbon and catalyst source on Silica/Si (100). Large yield of MWNT was observed at 900 C. MWNT grew perpendicular to the model support as seen by SEM. In another model catalyst study, iron salt clusters were deposited on silica/Si (100) by spin coating, controlling their diameters by solution concentration and speed of spinning. Agglomeration of clusters at high temperatures produces only MWNT on silica/Si (100). Cluster agglomeration can be reduced with strong support metal interaction such as with alumina. We deposited alumina on silica/Si (100) by atomic layer deposition, with conformal coatings on surface and low relative roughness. Alumina film was stable under reaction temperatures of 900 C. Cluster deposition on alumina by spin coating was difficult because of different surface acidity compared to silica. Clusters on alumina did not agglomerate at high reaction temperatures. We report effect of parameters such as the temperature of reaction, conditions of pretreatment such as reduction and oxidation of catalyst precursor, type of precursor, type of carbon source, and type of support material on growth of CNT. The role of spin coating in controlling the diameter of salt clusters deposited is discussed. We also report deposition of alumina on top of silica/Si (100) by atomic layer deposition and the effect of deposition and calcination temperatures on the alumina film integrity."

L’objectif était de développer et d’utiliser des nanoparticules hybrides de type«coeur-écorce» composées d’un coeur de silice dense entouré par des chaînes polymères fonctionnalisées par des ligands d’ATRP comme support catalytique pour la polymérisation du MMA par ATRP. Deux stratégies de synthèse de nanoparticules hybrides ont été élaborées. La première a consisté à immobiliser sur un support de silice, d’une manière covalente, des chaînes fonctionnelles synthétisées par NMP comportant des ligands capables de complexer le bromure de cuivre. Des nanoparticules de SiO2@polymère fonctionnel ayant de faibles densités de greffage en polymère ont été ciblées afin d’éviter leur recouvrement sur la surface. Cependant, les polymérisations n’étaient pas contrôlées probablement à cause d’un manque d’accessibilité de l’amorceur et des radicaux propageants aux complexes decuivre. Afin de rendre les catalyseurs supportés plus accessibles en solution, nous avons élaboré une seconde stratégie basée sur un système catalytique hybride réversible. Il consiste à immobiliser des chaînes α-fonctionnalisées par un motif donneur-accepteur de proton(DAD) via des liaisons hydrogène sur des particules de silice modifiées par un motif complémentaire (ADA). Des PMMA de masses molaires contrôlées ont été synthétisés avec des dispersités plus faibles que celles obtenues en ATRP homogène (en présence des chaînes libres). Après séparation du catalyseur du milieu réactionnel par centrifugation, nous avons montré qu’avec un excès du motif ADA, 96% du cuivre initialement introduit ont été récupérés. / The aim of this project is to develop hybrid nanoparticles bearing well definedpolymer arms as supported catalyst for the atom transfer radical polymerization of methylmethacrylate. This new generation of “semi heterogeneous" catalysts was prepared by twostrategies. The first consisted of immobilizing the polymer arms bearing the ligands enablingcoordination of copper bromide onto silica particles by covalent bonds. Hybrid nanoparticleswith low polymer grafting density were targeted to prevent the overlapping of chains on thesurface. Unfortunately, the polymerizations were not controlled probably due to a lack ofaccessibility of the initiator and propagating radicals to the copper complexes. To improve theaccessibility, a reversibly supported catalyst was developed via self-assembly using hydrogenbonding between chains α-functionalized by a proton donor-acceptor unit (DAD) and acomplementary unit (ADA) anchored on silica particles. These new hybrid materials wereefficient in the controlled radical polymerization of MMA, yielding polymers with controlledmolecular weights and dispersities narrower than those obtained for homogeneous ATRP.Moreover, after catalyst separation from the reaction medium by centrifugation, more than96% of the originally used copper was recovered.

Nanomaterials have attracted substantial attention in the area of catalysis due to the unique properties they exhibit such as high surface areas, intricate pore networks and unique morphologies. TiO2 has attracted attention as a catalyst since the discovery of its high photocatalytic activity by Fuishima and Honda in 1972. Given its high thermal stability, low cost, low environmental impact, and versatility, TiO2 is a widely used commercial catalyst and catalyst support. TiO2 is used in many applications such as photocatalysis is also an excellent support material for noble metals in a number of oxidative synthesis and pollution-control reactions. Though TiO2 is a widely used catalyst support, currently available commercial titanias often have low surface area and poor thermal and hydrothermal stability. While several methods reported in literature produce materials of higher surface area and more ideal porosity relative to commercially available titanias, these procedures generally involve inherent drawbacks including time-consuming, complicated, and expensive processes that are not industrially viable. Cost-effective, large-scale preparations of stable, high surface area, mesoporous TiO2 need to be developed. The work in this dissertation focuses on (1) producing high surface area stabilized TiO2 supports of controlled pore diameters and (2) the preparation of well dispersed Pt on these supports using industrially viable processes. The effects of dopants Al, La, Si, and Zr on the stability, surface area, and porosity of anatase TiO2 supports were investigated. Results show that dopants increased the surface area and thermal stability of anatase through structural modifications and grain growth inhibition. Stabilized titanias produced by this method demonstrated equivalent or higher thermal stability and surface area compared with pure anatase and previously reported materials after treatment at 400°C and 700°C including 22 mol% Al-TiO2 calcined at 400°C which had a surface area of 479 ± 39 m2/g, a pore volume of 0.46 ± 0.04 cm3/g, and a pore diameter of 2.9 ± 0.2 nm. Ten synthesis variables were examined and optimized using statistically designed experiments (DOEs). Equations were developed to predict the conditions to obtain the highest surface area and pore volume at the desired pore diameter and predict the pore diameter range that may be obtained for aluminum-modified anatase TiO2. Confirmation trials closely matched predicted surface areas, pore volumes, and pore diameters in all but one trial, demonstrating the power of DOEs in identifying and controlling synthesis variables in relatively few experiments. The structure of Al-modified anatase TiO2 was analyzed to determine the mechanism of Al stabilization. Surface Al stabilized TiO2 by lowering anatase surface energy, stabilizing planes of high surface energy which would otherwise join to achieve stabilization. Al in TiO2 lattice vacancies stabilized TiO2 through increasing lattice strain and limiting mass transport necessary for grain growth. Results demonstrate the importance of structure analysis of doped nanomaterials in the development of stabilized catalysts and catalyst supports. An industrially viable, one-pot synthesis of Pt supported on 22 mol% Al-modified anatase is presented. Pt dispersions as high as 54% (one-pot method) and 59% (DI method) have been obtained. Results show that this one-pot method and the DI method using our Al-modified supports are promising syntheses of highly dispersed Pt catalysts and demonstrate that the alumina-stabilized anatase support is superior to other many available anatase supports.

Afin de réduire la teneur en soufre des essences, l’hydrodésulfuration transforme les molécules soufrées en hydrocarbures en présence d’un catalyseur supporté (métaux de transition sulfurés : MoS2) et dopé (Co, Ni). Cette phase active, déposée sur des nanoparticules, présente un nombre plus important de défauts, sites actifs essentiels à la catalyse. Les nanoparticules ont un ratio S/V élevé, une grande réactivité de surface avec une juste utilisation des quantités de métaux. L’objectif de ce projet de thèse est de synthétiser des catalyseurs nanométriques de type coeur@coquille possédant une meilleure activité catalytique qu’un simple mélange mécanique de deux métaux sulfurés. Le coeur est composé de Fe3O4 ou de nanodiamants et la coquille de MoS2, NiMoS, CoMoS ou NiCoMoS, supporté sur du TiO2 ou de la γ-Al2O3. Une réaction modèle (HDS du thiophène) a été utilisée afin d’évaluer l’activité catalytique et d’optimiser la structure du catalyseur. L’étude portera sur les paramètres de synthèse et l’effet de la taille du coeur, la synthèse utilisée, les interactions entre le coeur et la coquille, le support, la (co)– promotion (Ni/Co) et l’activation par la température. / In hydrodesulfurization of fossil fuels, the sulfur levels are reduced by sulfur extraction from hydrocarbons by using supported catalysts (MoS2), doped (Co, Ni). Ultra-deep hydrodesulfurization will be achieved by improving new catalysts. Nanoparticles are a promising candidate with their high S/V ratio and permit to use the precise amount of metallic sulphide. The aim of this thesis is the synthesis of core@shell nanometric catalyst with improved activities. Core composed of Fe3O4 or nanodiamonds will be surrounded by a shell formed of MoS2, NiMoS, CoMoS or NiCoMoS, supported on TiO2, γ-Al2O3. Model reaction (thiophene) has allowed to compare conversion rates between each catalyst. Additionally, characterizations have provided a better understanding of the HDS catalyst structure and performances. Some factors have been investigated such as the size of the core, theinteractions between the core and the shell, the type of synthesis, the support chosen, the synergetic effect with doping ions and also the activation of the catalyst at low temperature.

Στην παρούσα διατριβή μελετήθηκε η ετερογενοποίηση της αντίδρασης φωτοξείδωσης του 2 μεθυλ 2 βουτενίου προς αλλυλικά υδροπεροξείδια με τη χρήση φωτοκαταλυτών που περιέχουν φουλερένιο C60 στηριγμένο σε οξειδικούς φορείς. Το φουλερένιο C60 είναι γνωστό για τη δράση του ως φωτοευαισθητοποιητής της παραγωγής οξυγόνου απλής κατάστασης (singlet oxygen) κατά την ακτινοβόληση με ορατή ακτινοβολία, το οποίο πραγματοποιεί την οξείδωση αλκενίων μέσω της αντίδρασης Schenck-Ene. Ήταν επιθυμητό να παρασκευαστούν καταλύτες στους οποίους το C60 να διαθέτει σταθερή ομοιοπολική σύνδεση με την επιφάνεια των φορέων. Αυτό πραγματοποιήθηκε μέσω της σύνθεσης ενός μονοϋποκατεστημένου μεθανοφουλερενικού παραγώγου, το οποίο συνδέθηκε με την επιφάνεια των φορέων (Grafting). Επιπλέον, τα υλικά σχεδιάστηκαν έτσι, ώστε να παρέχουν τη δυνατότητα της πλήρους και ελεγχόμενης αποκοπής κάτω από κατάλληλες συνθήκες, γεγονός που επιτρέπει τον έλεγχο της ακεραιότητας του C60 μετά από χρήση του σε αντίδραση ή μετά από θερμική ή χημική κατεργασία. Παράλληλα παρασκευάστηκαν καταλύτες με κλασικές μεθόδους σύνθεσης ετερογενών καταλυτών. Ως φορείς χρησιμοποιήθηκαν η SiO2 και η Al2O3. Τα υλικά που παρασκευάστηκαν, μελετήθηκαν ως προς τη φωτοκαταλυτική τους δράση ως προς την αντίδραση φωτοξείδωσης του 2 μεθυλ 2 βουτενίου και έγινε σύγκριση τους με βάση τον τρόπο παρασκευής και το φορέα στήριξης. Ακόμη, έγινε σύγκριση της ετερογενούς διεργασίας με την ανάλογη ομογενή. Τα υλικά εμφάνισαν στο σύνολο τους φωτοκαταλυτική δράση στην παραπάνω αντίδραση. Σε κάθε περίπτωση οι στηριγμένοι σε SiO2 καταλύτες εμφάνισαν υψηλότερη δραστικότητα από τους αντίστοιχους που παρασκευάστηκαν σε φορέα Al2O3. Ακόμη, τα υλικά που παρασκευάστηκαν με τη μέθοδο Grafting σε φορέα SiO2 παρουσίασαν την υψηλότερη δραστικότητα ανάμεσα σε όλους καταλύτες που εξετάστηκαν. Η δραστικότητά τους ήταν μάλιστα υψηλότερη και από την αντίστοιχη που παρατηρήθηκε κατά τη χρήση ισομοριακής ποσότητας C60 σε ομογενή αντίδραση αλλά μικρότερη από αυτή των γνωστών φωτοκαταλυτών Rose Bengal και TPP (5,10,15,20-τετραφαινυλο-21Η,23Η-πορφυρίνης). Τέλος, μελετήθηκε η θερμική σταθερότητα των υλικών κάτω από οξειδωτικές συνθήκες. Διαπιστώθηκε ότι η σύνδεση του C60 στην επιφάνεια των φορέων με τη μέθοδο Grafting εμφανίζει γενικά παρόμοια θερμική σταθερότητα σε σχέση με τους καταλύτες που παρασκευάστηκαν με τη μέθοδο του Υγρού Εμποτισμού. / The scope of this dissertation was the heterogenization of the photooxidation reaction of 2-methyl-2-butene towards allylic hydroperoxides with the use of fullerene C60 containing catalysts supported on oxide carriers. The reaction was known to be efficient under homogeneous conditions. The photooxidation of alkenes is conducted by singlet oxygen (1Δg) which is produced by photosensitizers. C60 is known for its photosensitizing ability to produce singlet oxygen under visible irradiation. It was a requirement that C60 would be connected through stable and covalent bonding to the catalysts surface. This became possible through the preparation of a monosubstituted methanofullerene which was subsequently attached through covalent bonding to the surface of the carriers (Grafting). Additionally, a key requirement in the materials design was to provide us with the ability of controlled -under the appropriate conditions- and quantitative detachment of the part which bears C60, and its recovery in solution. This is important because it allows us to examine possible changes in the C60 molecule after the material’s use in catalytic processes or after its thermal or chemical treatment. Employing well-known methods of heterogeneous catalysts synthesis catalysts with the corresponding % molar concentration in C60 were also prepared. The photocatalytic behavior of the prepared materials was investigated in the photooxidation reaction of 2-methyl-2-butene. The effect of carrier and preparation method was also investigated. A comparison was also made with the homogeneous case. The prepared materials were all efficient catalysts in the photooxidation reaction of 2-methyl-2-butene. In all cases, the supported on SiO2 catalysts showed higher reactivity than the corresponding ones supported on Al2O3. Moreover, the catalysts prepared with the Grafting method on SiO2 showed the highest reactivity among all the catalysts examined. The reactivity was higher than in the homogeneous case using equimolar solutions of C60 but lower to the reactivity recorded in the case of the well established photosensitizers Rose Bengal and Tetraphenylporphine (TPP). Finally, the thermal stability of the prepared materials under oxidative conditions was studied._It was realized that materials prepared through Grafting show generally similar thermal behavior with the catalysts prepared with the Incipient Wetness method.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Biodiesel is commonly produced by the transesterification reaction of oils or fats, in the presence of an alcohol of short chain and a catalyst. The development of suitable heterogeneous catalysts is important in order to propose alternative processes that are economically viable for biodiesel production as well as to facilitate the purification steps. In this research, two different catalysts (calcium oxide, CaO, and sodium zirconate, Na2ZrO3) were evaluated for biodiesel production in their free form and also supported on polymeric materials. Moreover, different reactor configurations were evaluated: reactor with magnetic stirring (MS), with recycle (RL) and with ultrasonic agitation (US). For the assays with CaO, the obtained reaction yield was approximately the same (80% of Fatty Acid Methyl Esther - FAME) in the three proposed reactor configurations. The reusability of CaO was evaluated in the ultrasonic reactor, but the results were not satisfactory for more than the first reaction cycle due to the catalyst deactivation. Moreover, the polymers evaluated to support CaO did no resist the reaction conditions. The catalyst Na2ZrO3 was evaluated in its free form and also supported in poly (vinyl alcohol) (PVA) and in reactors with magnetic stirring and with ultrasonic agitations. The obtained kinetic profile showed that, in the beginning, the reaction is slower in the ultrasonic reactor than in the reactor with magnetic stirring. However, at the end, both reactor configurations reached the same yield. A composite central planning was carried out to evaluate the optimal conditions of methanol:oil molar ration and catalyst loading (%) when using the free and supported catalysts and in the magnetic stirring and ultrasonic reactor. The answer was evaluated in terms of %FAME and viscosity. Reactions were performed at a fixed temperature and time (55°C and 6 h). Different answers were obtained for the different reactor configurations. For the free catalyst in the reactor with magnetic stirring, great values of %FAME and low values of viscosity are obtained in the central region of the composite central planning. For the free catalyst in the ultrasonic reactor, the best values are obtained at higher values of methanol:oil molar ratio and at the central region of the catalyst loading. For the supported catalyst in the reactor with magnetic stirring, the best values are obtained in the region of 5 to 7% of catalyst loading and methanol:oil molar ratio of 10:1 to 30:1. For the supported catalyst in the ultrasonic reactor, the best values are obtained at higher methanol:oil molar ratios, but at lower catalyst loadings. These results are associated with the mass transfers related to the different degree of agitation in both reactors and to the accessibility to active sites of the catalyst. The catalyst reuse was evaluated in five sequential baths without intermediated washings with solvents. For both reactor configurations, the Na2ZrO3 presented suitable stability. Results showed that the heterogeneous catalysis is a viable alternative for biodiesel production. Moreover, the utilization of a supported catalyst is feasible due to the easier catalyst recovery. The ultrasonic assisted reactor is also a suitable alternative. / Um dos processos mais comuns para a obtenção do biodiesel é a transesterificação de óleos ou gorduras, na presença de um álcool de cadeia curta e de um catalisador. O desenvolvimento de catalisadores heterogêneos eficientes é relevante na busca de processos alternativos que sejam economicamente viáveis para a produção comercial de biodiesel e para redução de etapas de purificação. Neste trabalho, estudou-se óxido de cálcio (CaO) e zirconato de sódio (Na2ZrO3) em suas formas livre e em suportado materiais poliméricos como catalisadores para produção de biodiesel utilizando-se diferentes configurações de reatores, sendo elas: reator com agitação magnética (MS), com reciclo (RL) e com agitação ultrassônica (US). Para os ensaios com CaO, utilizaram-se as três configurações de reatores propostas e o rendimento, que foi avaliado por meio do teor de ésteres no biodiesel também conhecido como FAME (Fatty Acid Methyl Esther), das reações foi semelhante (aproximadamente 80%). O reuso do CaO foi avaliado em agitação ultrassônica, porém não apresentou resultados satisfatórios além do primeiro ciclo, dada a inativação do catalisador. Além disso, os polímeros avaliados para suportar CaO não resistiram às condições reacionais. Para o catalisador Na2ZrO3 nas formas livre e suportado em poli (vinil álcool) (PVA), avaliou-se o perfil da %FAME ao longo da reação nos reatores com agitação magnética e em ultrassom. Os resultados mostraram que apesar da reação se proceder de forma mais lenta no início quando realizada em ultrassom, ao final do processo obteve-se conversão semelhante para as duas configurações de reator e catalisador. Para cada configuração de reator e condição do catalisador foi realizado um planejamento composto central (PCC) para se avaliar as condições ótimas de quantidade de catalisador e razão molar metanol:óleo, em termos de viscosidade e % FAME como resposta, utilizando o zirconato de sódio Na2ZrO3 como catalisador alcalino nas formas livre e suportado em (PVA) a uma temperatura de 55°C e tempo de reação de 6 h. Os resultados de %FAME e viscosidade foram avaliados pela superfície de resposta obtida para cada tipo de reator e forma de catalisador. Percebeu-se que na região central do PCC se encontram valores elevados de % de FAME e baixa viscosidade para o catalisador livre em reator MS. Para o reator US, foram encontrados valores maiores na região com elevadas RM e quantidade de catalisador na região central. Para o catalisador suportado em PVA, os melhores resultados de % de FAME e viscosidade foram encontrados, em reator MS, na região de 5 a 7% de catalisador e RM (metanol:óleo) de 10:1 a 30:1, enquanto para o reator US foram encontrados os melhores resultados também em elevada RM, porém com baixa quantidade de catalisador. Estes resultados podem ser explicados pelas diferentes velocidades de transferência de massa (agitação) nos dois reatores e pelas diferentes transferências de massa no interior do catalisador quando este se encontra na sua forma livre ou suportado. A reutilização do catalisador foi avaliada realizando-se bateladas sequenciais com o mesmo catalisador ao longo de cinco ciclos de reação nas mesmas condições da reação com o catalisador novo (1° ciclo), sem a utilização de solvente para lavagem. Para os dois tipos de reatores (MS e US) o Na2ZrO3 apresentou resultados satisfatórios para a transesterificação do óleo de soja, tanto para a forma livre quanto suportada em PVA e ainda apresentou comportamento que favorece a reutilização deste catalisador por ciclos consecutivos. Os resultados mostraram que a catálise heterogênea é uma alternativa viável para produção de biodiesel. Além disso, a utilização do catalisador suportado pode ser uma vantagem no que se refere a recuperação do catalisador do meio reacional. A agitação em banho ultrassônico também se mostrou uma alternativa viável. / Mestre em Engenharia Química

La polymérisation de l'éthylène en phase gaz en présence d'un système catalytique supporté en réacteurs à lit fluidisés reste le procédé le plus utilisé pour la production de polyéthylène à basse densité linéaire. De plus, dans le cas du polyéthylène à haute densité, celui-ci représente également une part non négligeable des plants de production à travers le monde. Le procédé en phase gaz offre de nombreux avantages dont un coût d'exploitations inférieures et une flexibilité supérieure en termes de production des différents types de polymères comparé aux autres procédés conventionnels. Cependant, au regard de la nature exothermique de la réaction de polymérisation, la vitesse de la production du polymère dans ces réacteurs est limitée par la vitesse à laquelle la chaleur produite par la réaction peut être évacuée. Si le réacteur ne permet pas l'évacuation de cette chaleur, l'augmentation de la vitesse de production résulterait en une croissance dramatique de la température au sein du réacteur et, par conséquent, à la fusion et l'agglomération du polymère, et finalement à l'arrêt du réacteur. Dans ce cas, dans le but d'avoir une vitesse de production plus importante, il est possible d'utiliser le réacteur susnommé en tant que mode d'opération condensé. Dans le cas de ce mode d'opération, le flux d'alimentation de la phase gaz du réacteur contient non seulement de l'éthylène, de l'azote, de l'hydrogène, et éventuellement un comonomère, mais également un agent condensant inerte (ACI) tels que le pentane ou l'hexane. Dans cette configuration, le flux d'alimentation est en partie liquéfié dans un échangeur de chaleur externe en le refroidissant sous le point de rosée du gaz. Par vaporisation de la phase liquide dans le réacteur, une quantité plus importante de chaleur peut être retirée de l'environnement du réacteur grâce à la chaleur latente associée à la vaporisation. Cela permet d'obtenir un rendement plus élevé de l'espace pour ce réacteur et par conséquent une vitesse de production supérieure / In the current thesis study it is intended to investigate the potential effect of the inert condensing agent (ICA) of n-hexane used in condensed mode operation on the solubility of ethylene in produced polyethylene (PE) and consequently the quality and rate of gas phase ethylene polymerization on supported catalyst under reactive conditions. This is the first time for such a study. Performing the set of designed polymerization reaction experiments using a lab-scale stirred-bed gas phase reactor, it is observed that the instantaneous rate of ethylene polymerization increases in the presence of n-hexane, thus supporting the initial speculation of the effect of n-hexane on the enhancement of the ethylene solubility in polymer known as “cosolubility” phenomenon. In order to have a better picture and understanding, the averaged instantaneous rate of polymerization in presence of n-hexane is normalized with the one without any n-hexane. Consequently, this helps to see that while the effect of n-hexane increases proportionally to its partial pressure in the gas phase composition, this effect is more pronounced at the initial steps during the course of polymerization. In the current thesis study for the first time, the Sanchez-Lacombe EOS as one of the most widely applied thermodynamic models in polymer industry is adapted and developed in order to study not only the solubility but also concentration of ethylene in polyethylene in the absence and presence of an inert condensing agent in order to quantify the speculated cosorption phenomenon under the reactive polymerization condition. By incorporating this thermodynamic model to describe the solubility of ethylene in polymer into a single particle model like Polymer Flow Model (PFM) to estimate the concentration and temperature gradient through a growing polymer particle, it is ultimately attempted to predict the effect of change in the process operating condition by addition of n-hexane as the ICA to the gas phase composition. Finally in the current thesis study, it is demonstrated how the thermal effect associated with the heat of sorption of ICAs can have a positive effect in terms of avoiding particle over-heating under certain circumstances like its temporary exposition to the defluidized regions inside a fluidized reactor (FBR) as a possible undesirable operating condition for this type of reactor set-ups

L'imprégnation, étape cruciale de la préparation de catalyseurs supportés pour l’hydrotraitement de coupes pétrolières (CoMo / y-Al2O3) , a été étudiée dans ce travail. L'objectif principal a été de déterminer les phénomènes physico-chimiques et les interactions entre la surface du support et les espèces en solution se produisant pendant cette étape puis faire le lien avec l'activité du catalyseur final.La formation directe et la stabilité de la solution (3 Co2+ ; H4Co2Mo10O386-) ont été étudiées de manière poussée en fonction du pH, de la concentration, du rapport Co/Mo. Cela a nécessité le développement de méthodes analytiques quantitatives (spectrométries Raman et UV-visible), réalisées via SIMPLISMA, un algorithme de traitement des données par analyses factorielles. L'étude de l'imprégnation de la solution (3 Co2+ ; H4Co2Mo10O386-) sur y-Al2O3 a mené à une meilleure compréhension de cette étape. Il a été montré que la conservation de cette espèce sur le support dépend principalement de la densité en atomes de Mo / nm², mais également du rapport Co/Mo et du pH initial de la solution d’imprégnation, tous ces paramètres étant liés entre eux. Cette étude a mis en évidence le rôle majeur du support, via ses propriétés surfaciques.L’intérêt d’utiliser (3 Co2+ ; H4Co2Mo10O386-) pour préparer de tels catalyseurs réside dans la proximité du cobalt et du molybdène. La phase active résultante est très bien dispersée et hautement promue, et ce même si le précurseur est décomposé sur le support lors de l’imprégnation. Enfin, la méthodologie développée au cours de ce travail est transposable à la préparation de tout type de catalyseur supporté. / Impregnation, crucial step of the preparation of supported catalysts used for hydrotreatment of petroleum fractions (CoMo / gamma-alumina), has been studied in this work. The main aim has consisted in determining the physico-chemical phenomena and the interactions between the support surface and the aqueous species during this step, and then linking these results to the activity of the final catalyst.The direct formation and stability of the (3 Co2+ ; H4Co2Mo10O386-) solution have been studied as a function of pH, concentration and Co/Mo ratio. This has required the developement of analytical quantitative methods (Raman and UV-visible spectroscopies) carried out thanks to SIMPLISMA, an algorithm of data treatment by factorial analysis. The study of impregnating (3 Co2+ ; H4Co2Mo10O386-) solutions onto gamma alumina has led to a best understanding of this step. It was showed that the conservation of these species on the support mainly depends on the surface density of molybdenum atoms per square nanometer, but also on the Co/Mo ratio and the initial pH of impregnating solutions, all these parameters being linked together. This study has underlined the major role of the surface properties of the support. The interest of using (3 Co2+ ; H4Co2Mo10O386-) solutions to prepare such catalysts lies in the proximity of cobalt and molybdenum. The resulting active phase is very well dispersed and highly promoted, even if the precursor is decomposed on the support during impregnation. Finally, the methodology developed in this work is transferable to the preparation of any supported catalyst.

Une démarche de type génie de la réaction chimique est appliquée à l'hydroformylation modèle d'oct-1-ène par des complexes lipophobes du rhodium préparés à partir de Rh(CO)2(acac) en phase liquide ionique ([Bmim][PF6]) ou en phase liquide ionique supportée sur silice. La réaction étant contrôlée par la concentration des réactifs dans la phase liquide ionique catalytique, une première étape a consisté à mesurer ces concentrations tant pour les deux gaz (H2 et CO) que pour l'oct-1-ène à différentes températures et pressions. Diverses méthodes de mesures sont utilisées pour la solubilité de l'oléfine : thermogravimétrie et chromatographie gazeuse après extraction multiple d’espace de tête, en présence de solvant (décane) et du produit de la réaction (nonanal). Le transfert gaz-liquide, qui peut conditionner la vitesse de réaction dans ces milieux visqueux, est également mesuré par une technique dynamique de variation de pression, en liquide ionique pur et en mélange biphasique liquide ionique-phase organique, dans un réacteur autoclave à autoaspiration de gaz par arbre creux. Une corrélation générale est proposée montrant une forte influence de la vitesse d'agitation.Une étude cinétique est réalisée en conditions de transferts non limitants en gaz-liquide organique-liquide ionique avec la TPPTS comme ligand. Les comportements habituels de l’hydroformylation  en  phase organique ou en phase aqueuse sont retrouvés : ordre voisin de 1 pour H2, inhibition par CO à forte concentration, énergie d'activation élevée. Si le turnover est convenable (70 h-1), le rapport n/iso est par contre très bas ce qui n'est pas en faveur de ce système catalytique. Quelques résultats permettent aussi une première analyse de la catalyse biphasique avec le ligand sulfoxantphos et de la catalyse en phase liquide ionique supportée sur silice avec la TPPTS. / A chemical reaction engineering approach is applied to the hydroformylation of 1-octene using lipophobic complexes of rhodium prepared from Rh(CO)2(acac) in ionic liquid phase ([Bmim] [PF6]) or in the ionic liquid phase supported on silica. As the reaction is controlled by the concentration of the reagents in the catalytic ionic liquid phase, the concentrations of both gases (H2 and CO) and also of 1-octene are measured at various temperatures and pressures as an initial step. Different methods are used for the measurement of the olefin solubility inside the ionic liquid: thermogravimetry and multiple headspace chromatography, in the presence of solvent (decane) and reaction product (nonanal). The gas-liquid mass transfer, which can be a rate controlling step in these viscous media, is also measured by a dynamic technique of pressure variation, both in case of pure ionic liquid and biphasic mixture of ionic liquid and organic phase, in an autoclave reactor with self induced stirrer. A general correlation is proposed showing the strong influence of the agitation speed. A kinetic study is realized in no gas–liquid nor organic–ionic liquid mass transfer limiting conditions (chemical regime) with TPPTS as ligand. The usual hydroformylation behaviour is observed, as already found in organic phase or in aqueous phase: order close to 1 for H2, inhibition by CO at large concentration, and high activation energy. If the turnover frequency is suitable (70 h-1), the n/iso ratio is very low which is not favourable to this catalytic system. Some experimental results also allow a first analysis of biphasic catalysis with sulfoxantphos ligand and of ionic liquid phase supported catalysis with TPPTS ligand.

The synthesis of dipyridyl functionalized polysulfones with improved hydrophilicity, enhanced membrane morphology and excellent ATRP polymeric ligand properties was conducted by the following method: (a) the formation of lithiated polysulfone from unmodified polysulfone and the subsequent reaction with 2,2'-vinylidenedipyridine in tetrahydrofuran at -78 oC under argon atmosphere to afford the corresponding dipyridyl functionalized polysulfone. The stoichiometry of the reaction affects the degree of functionalization of the product. When equimolar amounts of 2,2'-vinylidenedipyridine are added to the lithiated polysulfone, the degree of functionalization obtained was 45%. However, the addition of 10% and 20% molar excess of 2,2'-vinylidenedipyridine to the corresponding lithiated polysulfone produced dipyridyl functionalized polysulfones with degrees of functionalization of 80% and 95%, respectively; and (b) the membranes obtained from unmodified polysulfone as well as dipyridyl functionalized polysulfones were characterized by atomic force microscopy, scanning electron microscopy, pure water permeation measurements and contact angle measurements. Amine chain end functionalized polystyrene and poly(methyl methacrylate) were prepared by Atom Transfer Radical Polymerization (ATRP) methods as follows: (a) •-Aminophenyl functionalized polystyrene was prepared in quantitative yields by ATRP methods using a new primary amine functionalized initiator adduct, formed in situ by the reaction of 1-(4-aminophenyl)-1-phenylethylene and (1-bromoethyl)benzene in the presence of copper (I) bromide/2,2'-bipyridyl as catalyst in diethyl ether at 110 oC, for the polymerization of styrene.(b) New •-bis(aminophenyl) and •,ω-tetrakis(aminophenyl) functionalized polymers were prepared in quantitative yields by the ATRP method using the following synthetic strategy: (i) the initiation of styrene polymerization with a new primary diamine functionalized initiator adduct, generated in situ by the reaction of stoichiometric amounts of 1,1-bis(4-aminophenyl)ethylene with (1-bromoethyl)benzene in the presence of copper (I) bromide/2,2'-bipyridyl as catalyst, afforded •-bis(aminophenyl) functionalized polystyrene; and (ii) •-bis(aminophenyl) functionalized poly(methyl methacrylate) was prepared by the ATRP method using the primary diamine functionalized initiator adduct as initiator for methyl methacrylate polymerization; and (iii) well defined •,ω-tetrakis(aminophenyl) functionalized polystyrene was prepared by the post ATRP chain end modification reaction of •-bis(aminophenyl) functionalized polystyrene with 1,1-bis(4-aminophenyl)-ethylene at the completion of the polymerization reaction. (c) Similarly, •-bis(4-dimethylaminophenyl) functionalized polystyrene was prepared by using a new tertiary diamine functionalized initiator adduct, formed in situ by treatment of equimolar amounts of 1,1-bis[(4-dimethylamino)phenyl]-ethylene with (1-bromoethyl)benzene in the presence of copper (I) bromide/2,2'-bipyridyl as the catalyst in diphenyl ether at 110 oC for the initiation of styrene polymerization by the ATRP method. Furthermore, the ATRP of methyl methacrylate, initiated by the new tertiary diamine functionalized initiator adduct, produced •-bis(4-dimethylaminophenyl) functionalized poly(methyl methacrylate). In addition, •,ω-tetrakis(4-dimethylaminophenyl) functionalized polystyrene was synthesized via a post ATRP chain end modification reaction of •-bis(4-dimethylaminophenyl) functionalized polystyrene with equimolar amounts of 1,1-bis[(4-dimethylamino)phenyl]ethylene at the completion of the polymerization process. vi Quantitative yields of the different amine functionalized polymers with predictable number average molecular weights (Mn = 1.3 x 103 – 16.4 x103 g/mol), narrow molecular weight distributions (Mw/Mn = 1.03 – 1.29) and controlled chain end functionality were obtained. Polymerization kinetics data was employed to determine the controlled/living character of each ATRP reaction leading to the formation of the different amine chain end functionalized polymers. The polymerization processes were monitored by gas chromatographic analyses. Polymerization kinetics measurements for all reactions show that the polymerizations follow first order rate kinetics with respect to monomer consumption. The number average molecular weight of the amine functionalized polymers increases linearly with percentage monomer conversion and polymers with narrow molecular weight distribution were obtained. The ATRP of styrene, catalyzed by a novel dipyridyl functionalized polysulfone/CuBr supported catalyst system, afforded well defined polystyrene with predictable number average molecular weight and narrow molecular weight distribution in a controlled/living free radical polymerization process. The substituted 1,1-diphenylethylene initiator precursor derivatives and the functionalized polymers were characterized by nuclear magnetic resonance spectrometry, fourier transform infrared spectroscopy, thin layer chromatography, column chromatography, size exclusion chromatography, non-aqueous titrations, differential scanning calorimetry and thermogravimetrical analysis. / Chemistry / M. Sc. (Chemistry)