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The Binary Mixtures

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The Binary Mixtures UNIVERSITE MONTPELLIER II SCIENCES ET TECHNIQUES DU LANGUEDOC T H E S E pour obtenir le grade de DOCTEUR DE L'UNIVERSITE MONTPELLIER II Discipline : Chimie et Physicochimie des Matériaux (CNU 31) Ecole Doctorale : Sciences Chimiques (ED 459) Soutenue Le 10 juin 2011 par Caroline Bauer Metal ion extractant in microemulsions: where solvent extraction and surfactant science meet Composition du jury Prof. Jean-Francois Dufrêche Président du jury Prof. Gérard Cote ENSCP, France Rapporteur Prof. Kenneth Nash Washington State University, USA Rapporteur Dr. Julian Oberdisse CNRS/UM2, France Examinateur Dr. Jean-Claude Maurel Medesis Pharma, France Examinateur Prof. Jean-Francois Dufrêche ICSM/UM2, France Examinateur Prof. Thomas Zemb ICSM, France Directeur de thèse Dr. Olivier Diat CEA, France Invité Dr. Marie-Christine Charbonnel CEA, France Invité Acknowledgements This thesis would not have been possible unless the support and participation of many people. I am heartily thankful to my advisor, Pr. Thomas Zemb, whose encouragement, guidance and invaluable support from the initial to the final level enabled me to develop an understanding of the subject. I owe my deepest gratitude to Dr. Olivier Diat, for his perpetual advice, supervision and crucial contribution which made him a backbone of this research and so to this thesis. Pr. Kenneth Nash and Pr. Gérard Cote for their interest in that work and accepting to read and critically evaluate the manuscript as it is the role of the “rapporteurs”, I would like to thank heartfully. I am furthermore grateful to the other members of the jury, the “examinateurs”, Dr. Jean-Claude Maurel, Dr. Julian Oberdisse, Prof. Jean-François Dufreche an, Dr. Marie-Christine Charbonnel. Many thanks go in particular to Pr. Jean-Francois Dufrêche for the elaboration of theoretical model, critical comments, explanations on maths and programming, and his advice and guidance. It is a pleasure to pay tribute to the collaborators and to all the peoples who taught me the techniques and shared their experiences. Special thanks: to Veronique Dubois for the support in the lab and sample analysis, to the local contacts Dr. Bruno Demé at ILL, Dr. Michael Sztucki at ESRF and Dr. Jacques Jestin at LLB and especially to Dr. Sylvain Prevost from HZB for passing “extra” samples, fruitful discussion and his friendship, to the members of the laboratories that gave me the possibility to start this work in 2008 when ICSM was under construction, DEN/DPC/SECR/LSRM (CEA Saclay, Bat. 391, Dr. Christophe Moulin) and DEN/DRCP/SCPS/LEPS (CEA Marcoule, G1 lab CS, Dr. Clement Hill). Special thanks go to Hélène Martin for indispensable help with administration and bureaucratic matters, her kindness and sympathy in all situations! Furthermore I would like to thank for the assistance from the library, especially Fabienne Bel for the numerous commanded articles. My special thanks go to Cyril Micheau, Christine Cano and Maria Helminger for sharing the enthusiasm for this subject, their contribution and intelligent input. It was a real pleasure to work with you! Collective acknowledgements are owed to my colleagues at ICSM and CEA, office and laboratory members who made my time enjoyable, remembering all the nice moments and stimulating discussions shared during lunch, coffee break, and sports. I wish to thank my friends for the spent free time, the emotional support, entertainment and caring they provided. I could not mention personally one by one but the list is imprinted in my heart. Especially I would like to thank Dr. Wolfram Müller for his constant close friendship, for being part of my (little) family and sharing together so many special moments. I deeply thank my parents, Veronika and Hans-Joachim Bauer, who raised me, taught me, supported me, let me following my path abroad, and over all loved me. There are no words to thank Dr. Pierre Bauduin for guiding and advising me during the thesis. His intelligence and passion is a source of inspiration on all kind of scientific topics. His incredible calm character and faithful support during the final stages of this PhD is so appreciated. Thank you… This thesis is dedicated to my beloved son, Emile Bauduin, who brings plenty of joy to my life! Thèse financée par Introduction I Phase diagrams and packing parameter of extractants ___________________________17 I.1 Liquid-liquid extraction systems ______________________________________________ 19 I.1.1 General Considerations ___________________________________________________________ 19 I.1.2 Macroscopical aspects of extractant systems: an approach towards phase diagrams ____________ 22 I.1.3 Surface properties of extractants ____________________________________________________ 28 I.1.4 Extractant aggregates in solution ___________________________________________________ 31 I.2 Extractants revisited from literature: their surfactant nature interpreted in terms of the packing parameter ____________________________________________________________ 32 I.2.1 Geometric considerations for the description of amphiphiles aggregation ____________________ 32 I.2.2 Parameters influencing the packing parameter _________________________________________ 36 I.2.3 Design of a thermodynamic model describing aggregation in water/oil/extractant systems ______ 37 I.3 Three phase region in amphiphiles phase diagrams ______________________________ 56 I.3.1 “Third phase formation” in extactant systems: a phase diagram approach ____________________ 56 I.3.2 Mixing surfactant and co-surfactant (extractant): Three phasic microemulsion systems _________ 62 II Metal ion – effects in aqueous and organic phases _____________________________73 II.1 Spectroscopic analysis ______________________________________________________ 75 II.1.1 General description of UV measurements ____________________________________________ 75 II.1.2 Metal ion speciation in solution ____________________________________________________ 77 II.1.3 UV study of the uranyl solutions ___________________________________________________ 78 II.1.4 UV study of Neodymium in solution________________________________________________ 92 II.2 Supramolecular aggregation of C8G1 with salts ________________________________ 99 II.2.1 Aggregation of C8G1 in water and salt effects: a review ________________________________ 99 II.2.2 Experimental _________________________________________________________________ 102 II.2.3 Modeling of the SAXS spectra ___________________________________________________ 107 II.2.4 Results: fitting of the Scattering pattern of C8G1 micelles ______________________________ 112 II.2.5 Conclusion on the SAXS experiments _____________________________________________ 122 II.3 Flotation experiments to probe interfacial adsorption of metal ion on non ionic 2D- surfactant film _______________________________________________________________ 124 II.4 Conclusion of Chapter II __________________________________________________ 127 III Liquid interface functionalized by an ion extractant: the case of Winsor III microemulsions __________________________________________________________133 III.1 Winsor type microemulsions with TBP ______________________________________ 135 III.1.1 General introduction ___________________________________________________________ 135 III.1.2 Experimental ________________________________________________________________ 137 III.1.3 Phase diagrams – «Fish cuts» ____________________________________________________ 140 III.1.4 Microemulsion structure and effect of salt __________________________________________ 144 III.1.5 Determination of the film composition ____________________________________________ 153 III.2 Kinetics of liquid-liquid extraction – the effect of the presence of microemulsion on the transfer of uranyl ____________________________________________________________ 157 III.2.1 General Introduction __________________________________________________________ 157 III.2.2 Experimental of the uranyl extraction kinetics _______________________________________ 159 III.2.3 Influence of uranyl nitrate on the microemulsion phase diagram and microstructure _________ 161 III.2.4 Kinetics of uranyl nitrate extraction in Winsor III systems under static conditions ___________ 163 III.3 Conclusion of Chapter III _________________________________________________ 166 Conclusion Table of figures and tables FIGURE I-1 TRIANGULAR REPRESENTATION OF A TERNARY SYSTEM COMPOSED OF THREE PURE COMPOUNDS: A, B AND C .......................................................................................................................................................... 23 FIGURE I-2 EXPECTED PHASE DIAGRAM OF THE WATER-OIL-TBP SYSTEM WITH THE MONOPHASIC (1Φ, SEE THE REPRESENTATION AS A TEST TUBE ON THE RIGHT) AND BIPHASIC REGIONS (2Φ) ARE DELIMITED BY THE DARK SQUARES. THE DASHED LINE CORRESPONDS TO MIXTURES WITH FIXED WATER TO OIL RATIO 1/1, THE BLUE DOT CORRESPONDS TO A TYPICAL EXTRACTION COMPOSITION CONTAINING 30% OF TBP AND EQUAL AMOUNT OF WATER AND OIL (SEE THE TUBE REPRESENTATION ON THE LEFT WITH OIL PHASE IN YELLOW AND AQUEOUS PHASE IN BLUE), FULL LINES CORRESPONDS TO TIE LINES IN THE BIPHASIC REGION THE TWO LIMITS OF THESE LINES GIVING THE COMPOSITION OF THE TWO PHASES IN EQUILIBRIUM. ....................................... 24 FIGURE I-3 WATER/HEXANE/NAAOT TERNARY PHASE DIAGRAM. L2 DENOTES THE OIL-RICH ONE PHASE REGION, F REPRESENTS A SURFACTANT RICH HEXAGONAL PHASE AND D STANDS FOR THE LAMELLAR PHASE .......... 25 FIGURE I-4 PHASE DIAGRAMS FOR THE NADEHP/WATER/N-HEPTANE/NACL AT 25°C,
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