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Etude expérimentale et modélisation d'un procédé de séparation de cobalt et de nickel par extraction liquide-liquide / Experimental study and modelling of cobalt-nickel separation by solvent extractionCoilhac, Marie 28 June 2016 (has links)
L’objectif de cette thèse est de modéliser et d’optimiser l’unité de séparation du cobalt et du nickel par extraction liquide-liquide d’un procédé hydrométallurgique. La méthodologie adoptée a consisté dans un premier temps à étudier et modéliser séparément les équilibres d’extraction de chaque métal présent dans la solution industrielle (cobalt, nickel, magnésium, manganèse et zinc), par l’acide phosphinique CYANEX® 272 dilué dans un mélange d’hydrocarbures inertes. Un modèle thermodynamique multi-élémentaire permettant de simuler l’extraction de mélanges des 5 métaux a ensuite été élaboré sur la base des équilibres d’extraction et des constantes apparentes associées ainsi obtenus. Dans un second temps, le modèle multi-élémentaire a été utilisé pour modéliser le procédé continu de séparation du cobalt et du nickel. Ce procédémulti-étagé à contre-courant comporte plusieurs étapes : l’extraction, le lavage, l’élution cobalt et l’élution zinc. Dans le modèle développé, les concentrations en métaux dans les deux phases, les pH dans les différents étages ainsi que la consommation en réactifs, sont calculés à l’aide d’une méthode itérative. Cet outil de simulation du procédé a permis d’identifier des conditions opératoires optimales, pour lesquelles le rendement d’extraction du cobalt de 95% visé est atteint avec une économie en soude tout à fait significative. Les conditions proposées ont ensuite été validées par des campagnes de tests en continu à l’échelle pilote. / This thesis work aims at modelling and optimizing the step of cobalt and nickel separation by solvent extraction, for a hydrometallurgical process. The first stage of the adopted methodology consisted in studying and modelling separately the extraction equilibria of each metal present in the industrial feed solution (cobalt, nickel, magnesium, manganese and zinc) by the phosphinic acid CYANEX® 272 diluted in an inert hydrocarbon mixture. The resulting extraction reactions and their associated equilibrium constants are the basis of a multi-element thermodynamic model that simulates the batch extraction of mixtures of the 5 metals. The next stage of the study consisted in modelling the continuous process of cobalt and nickel separation, based on the multi-element thermodynamic model. This multi-stage process operated counter-currently includes different steps : extraction, scrubbing, cobalt stripping and zinc stripping. In the model developed, the metal concentrations in both phases, the pH in all the stages, and the reagent consumptions are calculated by an iterative method. This simulation tool allowed identifying optimal operational conditions, for which the cobalt extraction yield of 95% is reached with significant caustic soda savings. Then the proposed conditions have been validated through continuous pilot tests.
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Tratamento de ?gua de produ??o de petr?leo visando o aproveitamento na obten??o de barrilhaNunes, Shirlle Katia da Silva 19 July 2013 (has links)
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Previous issue date: 2013-07-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The petroleum production is associated to the produced water, which has dispersed and
dissolved materials that damage not only the environment, but also the petroleum
processing units. This study aims at the treatment of produced water focusing mainly on
the removal of metals and oil and using this treated water as raw material for the
production of sodium carbonate. Initially, it was addressed the removal of the following
divalent metals: calcium, magnesium, barium, zinc, copper, iron, and cadmium. For this
purpose, surfactants derived from vegetable oils, such as coconut oil, soybean oil, and
sunflower oil, were used. The investigation showed that there is a stoichiometric
relationship between the metals removed from the produced water and the surfactants used
in the process of metals removal. It was also developed a model that correlates the
hydrolysis constant of saponified coconut oil with the metal distribution between the
resulting stages of the proposed process, flocs and aqueous phases, and relating the results
with the pH of the medium. The correlation coefficient obtained was 0.963. Next, the
process of producing washing soda (prefiro soda ahs ou sodium carbonate) started. The
resulting water from the various treatment approaches from petroleum production water
was used. During this stage of the research, it was observed that the surfactant assisted in
the produced water treatment, by removing some metals and the dispersed oil entirety. The
yield of sodium carbonate production was approximately 80%, and its purity was around
95%. It was also assessed, in the production of sodium carbonate, the influence of the type
of reactor, using a continuous reactor and a batch reactor. These tests showed that the
process with continuous reactor was not as efficient as the batch process. In general, it can
be concluded that the production of sodium carbonate from water of oil production is a
feasible process, rendering an effluent that causes a great environmental impact a raw
material with large scale industrial use / A produ??o do petr?leo ? associada ? ?gua produzida, que apresenta materiais
dispersos e dissolvidos que prejudicam n?o s? o meio ambiente, mas tamb?m, as unidades
de processamento de petr?leo. Este trabalho objetiva o tratamento da ?gua de produ??o
enfocando, principalmente, a remo??o de ?leo e de metais e a utiliza??o desta ?gua tratada
como mat?ria-prima para produ??o de barrilha. Inicialmente, verificou-se a remo??o dos
seguintes metais bivalentes: c?lcio, magn?sio, b?rio, zinco, cobre, ferro e o c?dmio.
Utilizou-se para este fim tensoativos derivados de ?leos vegetais, tais como: ?leo de coco,
?leo de soja e ?leo de girassol. Verificou-se que existe uma rela??o estequiom?trica entre
os metais removidos da ?gua de produ??o e os tensoativos utilizados no processo.
Tamb?m, desenvolveu-se um modelo que relaciona a constante de hidr?lise do ?leo de
coco saponificado com a distribui??o do metal entre as fases resultantes do processo
proposto, fases floco e aquosa, relacionando os resultados com o pH do meio. Obteve-se
um coeficiente de correla??o na ordem de 0,963. Em seguida, iniciou-se o processo de
obten??o da barrilha. Utilizou-se a ?gua resultante das diversas correntes de tratamento da
?gua produzida. Nesta etapa do trabalho, observou-se que o tensoativo auxiliava no
tratamento da ?gua de produ??o, removendo parte dos metais e a totalidade do petr?leo
disperso. O rendimento da produ??o da barrilha foi da ordem de 80% e sua pureza ficou
em torno de 95%. Avaliou-se, ainda, no processo de produ??o da barrilha, a influ?ncia do
tipo de reator, utilizando-se um reator cont?nuo e um reator em batelada. Estes ensaios
mostraram que o processo cont?nuo n?o foi t?o eficiente quanto o processo em batelada.
De forma geral, pode-se concluir que a produ??o de barrilha a partir da ?gua de produ??o
de petr?leo ? um processo vi?vel, transformando um efluente que causa grande impacto
ambiental em mat?ria-prima de larga utiliza??o industrial / 2020-01-01
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Système VEGF/VEGFR : conception et évaluation de molécules ciblées et régulation potentielle par les métaux / VEGF/VEGFR system : design and evaluation of targeted compounds and possible regulation by transition metalsReille-Seroussi, Marie 24 September 2014 (has links)
Dans les thérapies anticancéreuses, les traitements anti-angiogéniques agissant sur l’axe VEGF/VEGFR ont une place importante en clinique. Dans ce contexte, nous avons conçu et évalué l’activité de nouveaux inhibiteurs de l’interaction VEGF/VEGFR. Une première approche a été la conception de molécules antagonistes du VEGFR1. Différents analogues hétérocycliques dérivant d’un composé de type (3-carboxy-2-ureido) thiophène ont été synthétisés. Des réactivités chimiques intéressantes ont été mises en évidence, mais l’activité biochimique de ces molécules ne s’est pas révélée concluante. Une seconde approche reposant sur la conception de peptides ciblant le VEGF a alors été initiée. A partir d’un peptide cyclique connu de 19 résidus ayant une affinité submicromolaire pour le VEGF, de nouveaux peptides et peptidomimétiques ont été développés.L’objectif a été de concevoir des composés de structures chimiques potentiellement plus simples et plus stables en milieu biologique, tout en optimisant l’affinité pour le VEGF. L’interaction de ces peptides avec le VEGF a été étudiée in vitro par ELISA et ITC, ainsi que par cristallographie pour le composé le plus affin. En parallèle, nous avons étudié l’effet du cuivre et d’autres métaux divalents sur l’interaction VEGF/VEGFR1. Au travers d’expériences réalisées au laboratoire ainsi qu’en collaboration, nous avons montré que certains métaux étaient capables non seulement d’inhiber l’interaction VEGF/VEGFR1 mais également d’induire une dimérisation non classique du domaine 2du récepteur. Sachant que les métaux, et en particulier le cuivre, sont connus pour jouer un rôle important dans l’angiogenèse, cette découverte apporte de nouveaux éléments de réponse sur leur mécanisme d’action. Ce travail de thèse s’inscrit donc non seulement dans une démarche de développement de nouveaux composés anti-angiogéniques mais également de compréhension du mécanisme de régulation de l’angiogenèse. / Inhibiting angiogenesis is an effective strategy of targeting therapy against cancer. In thiscontext, we develop an antiangiogenic strategy consisting in the design and evaluation of compoundsblocking the VEGF/VEGFR interaction. The first approach was the conception of antagonists of theVEGFR1. Starting from a (3-carboxy-2-ureido) thiophene hit, a variety of heterocyclic analogs wasdeveloped. Interesting chemical observations were made during the synthesis, but no optimization ofthe biochemical activity was achieved. The second approach was the design of peptides that bind tothe receptor-recognition surface of the VEGF. Starting from a cyclic peptide known to bind to theVEGF with a sub-micromolar affinity, new peptides and peptidomimetics were developed. Thestrategy was to design simplified and potentially more stable compounds, and to improve at thesame time the VEGF affinity. The interaction of VEGF with these ligands was studied in vitro by ELISAand ITC experiments, as well as X-ray diffraction for the best compound. Moreover, the investigationof the effects of copper and other divalent metals on the VEGF/VEGFR1 interaction was undertaken.Experiments realized in the laboratory and in collaboration showed that metals were able to displacethe VEGF/VEGFR1 interaction and to induce the dimerisation of the domain 2 of the receptor. Metalsare well known to play an important role in angiogenic phenomena, but their specific targets are stilla matter of debate. In this context, this discovery brings new response elements regarding theirmechanisms of action. Therefore, the objectives of this PhD thesis were the development of newantiangiogenic compounds, as well as the understanding of some aspects of the regulation of angiogenesis.
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