Thomas Zemb
University of Montpellier, Institut de Chimie Séparative de Marcoule, Department Member
- Surfactants, Surfactant Science & Technology, Surface Chemistry, Small Angle X Ray Scattering, Multidisciplinary, Langmuir, and 24 moreStability, Microstructure, Water, Neutron Scattering, Analytical Chemistry, Osmotic pressure, Surfactant, Ion Exchange, CHEMICAL SCIENCES, Silica, Soft Matter, Self Assembly, X-ray imaging, Magnetic Resonance Spectroscopy, Physical sciences, Small angle X-ray and neutron scattering, Engineering, Block Copolymer, Interfacial Tension, Inorganic Chemistry, Mechanics, Crystallization, Elasticity, and X Rays(Stability, Microstructure, Water, Neutron Scattering, Analytical Chemistry, Osmotic pressure, Surfactant, Ion Exchange, CHEMICAL SCIENCES, Silica, Soft Matter, Self Assembly, X-ray imaging, Magnetic Resonance Spectroscopy, Physical sciences, Small angle X-ray and neutron scattering, Engineering, Block Copolymer, Interfacial Tension, Inorganic Chemistry, Mechanics, Crystallization, Elasticity, and X Rays)edit
- Curriculum Vitae: Prof. Dr. Thomas N Zemb Born 1953 in Hamburg (Germany, French national), married with 3 children, I... moreCurriculum Vitae: Prof. Dr. Thomas N Zemb
Born 1953 in Hamburg (Germany, French national), married with 3 children, I had a French-German initial education. After "baccalaureat" obtained in 1969, I studied physics in Paris, with biophysics-biochemistry options. I prepared a practical "Diplomarbeit" in nuclear physics at ETH Zurich, defended in September 1972.
phD Biophyics INstitu Curie 1978, and D. SC. In Solid state physics Orsay 1985
Positions since 1976:
1976: Agrégation de physique, then teaching in high schools and at Ecole Normale Supérieure de Saint Cloud.
Since 1979: Staff scientist at "Service de Chimie moléculaire” (CEA-Saclay)".
1985: staff scientist at Saclay (Dpet Phys Chem) and ILL Grenoble then visiting fellow at Australian National Univ. (Pr. B. Ninham and Pr. J. W. White 1985-1987; 1989-1990).
Since 1992: full Professor at INSTN (Institut des Sciences et Techniques Nucléaires).
Visiting professor at MPIKG Potsdam and University Regensburg, own research themes: new solvent formulation and excitation of ions at interfaces (via Gay-Lussac one semester fellowships)
Responsibilities within fundamental research Division of CEA:
2013- : Principal Investigaor ot of ERC project REE_CYCLE : Recycling rare earths with low harmful emissions
2007-2014: Director of the Institute for separation chemistry in Marcoule
1992-2007: in charge of the group "Chimie de la Matière Ultra-divisée”, Deputy-head and then Head of Laboratoire Claude Fréjacques, an associated laboratory with fifty staff CEA-CNRS, UMR 331.
1987-1999: in charge of Small Angle X-ray Scattering laboratory that I created within CEA/DPC/SCM.
Functions:
1994-1999, Responsible of research program: “Architecture moléculaire” at CEA.
1993-1997, Coordinator of the French Interdisciplinary Colloid group: “Systèmes colloïdaux mixtes” CEA/CNRS, funding together 44 teams working in the field of colloids (physics, chemistry and biology).
2000-2006, Co-director of the GDR French-German CNRS/Max Planck “Complex fluids in two and one half dimensions”, funding together 7 French and 7 German research teams (co-dir: Pr Dr H. Moehwald).
1998-2001, CEA-Representative at “Science advisory committee” at ESRF, Grenoble.
1995-2010, Nominated member of the ”Comité national de la recherche scientifique“, in Chemistry (3 terms)
2008-presnt : co-responsible for France of the CNRS/MPG common lab (LIA) ° RECYCLING”
2012-2014 : Founding Director of the Labex “Chemisyst” of Montpellier ( 2012-2015)
2014- present Mercator professor at TU Berlin
Awards:
(i) Prize of best thesis awarded as “Prix de la division de Chimie Physique”, Société Française de Chimie in 1985 ; (ii) National prize in Physical Chemistry, given yearly by the French Academy of Sciences: "Prix Paul Pascal", awarded in 2003: (iii) Price of the European colloid and interface society (process by anonymous nomination – not by candidature) and by vote: “for the discovery of self-assembled hollow icosahedra which mimic viruses” (made the cover page in Nature + publications in Science ad PNAS).
Laureate of the 2009 Humboldt-Gay-Lussac award in Chemistry: linked to my collaboration in sonochemistry and separation chemistry with MPI-Potsdam.
2013 Thomas Graham medal in ion separation chemistry awarded by the DKG(Curriculum Vitae: Prof. Dr. Thomas N Zemb<br />Born 1953 in Hamburg (Germany, French national), married with 3 children, I had a French-German initial education. After "baccalaureat" obtained in 1969, I studied physics in Paris, with biophysics-biochemistry options. I prepared a practical "Diplomarbeit" in nuclear physics at ETH Zurich, defended in September 1972. <br />phD Biophyics INstitu Curie 1978, and D. SC. In Solid state physics Orsay 1985<br />Positions since 1976:<br />1976: Agrégation de physique, then teaching in high schools and at Ecole Normale Supérieure de Saint Cloud.<br />Since 1979: Staff scientist at "Service de Chimie moléculaire” (CEA-Saclay)".<br />1985: staff scientist at Saclay (Dpet Phys Chem) and ILL Grenoble then visiting fellow at Australian National Univ. (Pr. B. Ninham and Pr. J. W. White 1985-1987; 1989-1990).<br />Since 1992: full Professor at INSTN (Institut des Sciences et Techniques Nucléaires).<br />Visiting professor at MPIKG Potsdam and University Regensburg, own research themes: new solvent formulation and excitation of ions at interfaces (via Gay-Lussac one semester fellowships) <br />Responsibilities within fundamental research Division of CEA:<br />2013- : Principal Investigaor ot of ERC project REE_CYCLE : Recycling rare earths with low harmful emissions<br />2007-2014: Director of the Institute for separation chemistry in Marcoule <br />1992-2007: in charge of the group "Chimie de la Matière Ultra-divisée”, Deputy-head and then Head of Laboratoire Claude Fréjacques, an associated laboratory with fifty staff CEA-CNRS, UMR 331.<br />1987-1999: in charge of Small Angle X-ray Scattering laboratory that I created within CEA/DPC/SCM.<br />Functions:<br />1994-1999, Responsible of research program: “Architecture moléculaire” at CEA.<br />1993-1997, Coordinator of the French Interdisciplinary Colloid group: “Systèmes colloïdaux mixtes” CEA/CNRS, funding together 44 teams working in the field of colloids (physics, chemistry and biology).<br />2000-2006, Co-director of the GDR French-German CNRS/Max Planck “Complex fluids in two and one half dimensions”, funding together 7 French and 7 German research teams (co-dir: Pr Dr H. Moehwald).<br />1998-2001, CEA-Representative at “Science advisory committee” at ESRF, Grenoble.<br />1995-2010, Nominated member of the ”Comité national de la recherche scientifique“, in Chemistry (3 terms)<br />2008-presnt : co-responsible for France of the CNRS/MPG common lab (LIA) ° RECYCLING”<br />2012-2014 : Founding Director of the Labex “Chemisyst” of Montpellier ( 2012-2015)<br />2014- present Mercator professor at TU Berlin<br /><br />Awards:<br />(i) Prize of best thesis awarded as “Prix de la division de Chimie Physique”, Société Française de Chimie in 1985 ; (ii) National prize in Physical Chemistry, given yearly by the French Academy of Sciences: "Prix Paul Pascal", awarded in 2003: (iii) Price of the European colloid and interface society (process by anonymous nomination – not by candidature) and by vote: “for the discovery of self-assembled hollow icosahedra which mimic viruses” (made the cover page in Nature + publications in Science ad PNAS). <br />Laureate of the 2009 Humboldt-Gay-Lussac award in Chemistry: linked to my collaboration in sonochemistry and separation chemistry with MPI-Potsdam.<br />2013 Thomas Graham medal in ion separation chemistry awarded by the DKG)edit
We have studied the microemulsion and lamellar phases of two of the most commonly described systems based on nonionic C12E5 and ionic AOT surfactants. We show that C12E5 is best described by the symmetric disordered open connected... more
We have studied the microemulsion and lamellar phases of two of the most commonly described systems based on nonionic C12E5 and ionic AOT surfactants. We show that C12E5 is best described by the symmetric disordered open connected lamellar model (DOC-lamellar), contrary to the more commonly employed standard flexible model. In the case of AOT, the bicontinuous microemulsion structure is best described by the standard flexible model at high temperatures. Around room temperature, connected cylinders in a molten cubic crystal phase are the only description which corresponds to the data. In the lamellar phase, around one third of the available surface area is lost in fluctuations and defects. Comparing structurally predictive models with results from conductivity measurements show that salt adsorption in the hydrated ethoxy groups is dominant for C12E5 (nonionic). For AOT, our conductivity measurements clarify the role of tortuosity versus cation absorption.
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Research Interests: Engineering, Acoustics, Materials Science, Technology, Cavitation, and 2 moreThe and CHEMICAL SCIENCES(The and CHEMICAL SCIENCES)
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Abstract Amphiphilic association in room-temperature ionic liquids (RT-ILs) — a “green” solvent shows analogies as well as clear differences from self-assembly in water. In this review, we summarize the known features of amphiphilic... more
Abstract Amphiphilic association in room-temperature ionic liquids (RT-ILs) — a “green” solvent shows analogies as well as clear differences from self-assembly in water. In this review, we summarize the known features of amphiphilic association structures in the form of micelles, microemulsions, vesicles and lyotropic liquid-crystalline phases in ionic liquids. Most of the methods making use of association to control reactivity could be developed also in RT-ILs and we give a few recently published examples of this strategy.
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In this work, we developed a general theoretical description of ternary solutions of small molecules under a centrifugal field, from which we obtained the centrifugation map (CMap) as a general tool to understand observations or to... more
In this work, we developed a general theoretical description of ternary solutions of small molecules under a centrifugal field, from which we obtained the centrifugation map (CMap) as a general tool to understand observations or to predict composition profiles in centrifugal fields of arbitrary strength. The theoretical formalism is based on the classical density functional theory with established models for liquid mixtures. Thermodynamics also yields a general criterion for apparent aggregation. The strength of the CMap approach is illustrated for a ternary model system where ethanol is a co-solvent.
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Transmission microscopy with soft X-rays (TXM) is applied to image in-situ polyelectrolyte assemblies in aqueous environment. The method is element specific and at this stage exhibits a lateral resolution of 20 nm. With the specific... more
Transmission microscopy with soft X-rays (TXM) is applied to image in-situ polyelectrolyte assemblies in aqueous environment. The method is element specific and at this stage exhibits a lateral resolution of 20 nm. With the specific examples of hollow capsules and full spheres made of PAH/PSS polyelectrolyte multilayers, it is shown quantitatively that heat treatment irreversibly reduces the water content in the membrane. These experiments complement those reported recently on the polyion system PDADMAC/PSS, which shows a different glass-transition behavior. Finally, the potential and present limitations of TXM are discussed.
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The phase transfer of ions is driven by gradients of chemical potentials rather than concentrations alone (i.e., by both the molecular forces and entropy). Extraction is a combination of high-energy interactions that correspond to... more
The phase transfer of ions is driven by gradients of chemical potentials rather than concentrations alone (i.e., by both the molecular forces and entropy). Extraction is a combination of high-energy interactions that correspond to short-range forces in the first solvation shell such as ion pairing or complexation forces, with supramolecular and nanoscale organization. While the latter are similar to the long-range solvent-averaged interactions in the colloidal world, in solvent extraction they are associated with lower characteristic lengths of the nanometric domain. Modeling of such complex systems is especially complicated because the two domains are coupled, whereas the resulting free energy of extraction is around kBT to guarantee the reversibility of the practical process. Nevertheless, quantification is possible by considering a partitioning of space among the polar cores, interfacial film, and solvent. The resulting free energy of transfer can be rationalized by utilizing a combination of terms which represent strong complexation energies, counterbalanced by various entropic effects and the confinement of polar solutes in nanodomains dispersed in the diluent, together with interfacial extractant terms. We describe here this ienaics approach in the context of solvent extraction systems; it can also be applied to further complex ionic systems, such as membranes and biological interfaces.
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There is a rise in interest in the rational design of new surfactants that possess various chemical or biological functionalities and self-assemble into tunable and predictable aggregate structures. In the past few years new amphiphiles... more
There is a rise in interest in the rational design of new surfactants that possess various chemical or biological functionalities and self-assemble into tunable and predictable aggregate structures. In the past few years new amphiphiles (many of which are chiral and ...
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Research Interests: Engineering, Thermodynamics, Chemistry, Chemical Physics, Microemulsion, and 13 moreCurvature, Physical sciences, Free Energy, Temperature Dependence, CHEMICAL SCIENCES, Heat Capacity, Gaussian, Microstructures, Thermal Properties, Factor structure, Gaussian Curvature, Thermal Expansion, and Volume Fraction
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Self-assembled structures having a regular hollow icosahedral form (such as those observed for proteins of virus capsids) can occur as a result of biomineralization processes, but are extremely rare in mineral crystallites. Compact... more
Self-assembled structures having a regular hollow icosahedral form (such as those observed for proteins of virus capsids) can occur as a result of biomineralization processes, but are extremely rare in mineral crystallites. Compact icosahedra made from a boron oxide have been reported, but equivalent structures made of synthetic organic components such as surfactants have not hitherto been observed. It is, however, well known that lipids, as well as mixtures of anionic and cationic single chain surfactants, can readily form bilayers that can adopt a variety of distinct geometric forms: they can fold into soft vesicles or random bilayers (the so-called sponge phase) or form ordered stacks of flat or undulating membranes. Here we show that in salt-free mixtures of anionic and cationic surfactants, such bilayers can self-assemble into hollow aggregates with a regular icosahedral shape. These aggregates are stabilized by the presence of pores located at the vertices of the icosahedra. The resulting structures have a size of about one micrometre and mass of about 1010 daltons, making them larger than any known icosahedral protein assembly or virus capsid. We expect the combination of wall rigidity and holes at vertices of these icosahedral aggregates to be of practical value for controlled drug or DNA release.
Research Interests: Chemical Engineering, Chemistry, Crystallography, Self Assembly, Crystallization, and 15 moreBiomineralization, Medicine, Multidisciplinary, Nature, Cationic polymerization, Capsid, Membrane, Anions, Glycerol, Solutions, Surface Active Agents, Vesicle, Cations, Molecular Structure, and Myristic acid
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The thermodynamics and structural properties of flexible and rigid nonionic water/oil/surfactant microemulsions have been investigated using a two level-cut Gaussian random field method based on the Helfrich formalism. Ternary stability... more
The thermodynamics and structural properties of flexible and rigid nonionic water/oil/surfactant microemulsions have been investigated using a two level-cut Gaussian random field method based on the Helfrich formalism. Ternary stability diagrams and scattering spectra have been calculated for different surfactant rigidities and spontaneous curvatures. A more important contribution of the Gaussian elastic constants compared to the bending one is observed on the ternary stability diagrams. Furthermore, influence of the spontaneous curvature of the surfactant points out a displacement of the instability domains which corresponds to the difference between the spontaneous and effective curvatures. We enlighten that a continuous transition from a connected water in oil droplets to a frustrated locally lamellar (oil in water in oil droplets) microstructure is found to occur when increasing the temperature for an oil-rich microemulsion. This continuous transition translated in a shift in the scattering functions, points out that the phase inversion phenomenon occurs by a coalescence of the water droplets.
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Swollen cubic lyotropic ternary phases with Pn3m symmetry and reduced hardness were obtained from a specific binary mixture of cubic phase-forming (phytantriol) and lamellar phase-forming (decaglycerol monooleate) compounds. The... more
Swollen cubic lyotropic ternary phases with Pn3m symmetry and reduced hardness were obtained from a specific binary mixture of cubic phase-forming (phytantriol) and lamellar phase-forming (decaglycerol monooleate) compounds. The microstructures were determined by using a small-angle x-ray scattering technique. The softness and temperature-induced phase transitions were investigated by means of rheology. The incorporation of a surface-active fragrance compound (linalool) at concentrations up to 6 wt. % induced a structural transition toward a softer Im3m bulk cubic phase with longer water channels. Higher linalool concentrations allowed for the spontaneous dispersion of the bulk cubic phase into microscopic particles with a cubic structure (cubosomes).
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Short-chain sulfosuccinates are an intermediary between hydrotropes and classical surfactants. This dynamic snapshot illustrates the fluctuating, weak aggregation in an aqueous solution.
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We generate all possible thermalized microstructures of two non miscible liquids separated by a known amount of w/o interface and locate their domains of stability in ternary phase diagrams. Frus- trated and unfrustrated bicontinuous... more
We generate all possible thermalized microstructures of two non miscible liquids separated by a known amount of w/o interface and locate their domains of stability in ternary phase diagrams. Frus- trated and unfrustrated bicontinuous microemulsions appear near instabilities related to transition towards lyotropic liquid crystals. Microstructures can be distinguish via qualitative features on the scattering.
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Even in the absence of surfactants, polymers, or particles, spontaneous emulsions produced by dilution with water can be stable over days. This "Ouzo effect" used by the industry is obtained by rapid dilution from an identified... more
Even in the absence of surfactants, polymers, or particles, spontaneous emulsions produced by dilution with water can be stable over days. This "Ouzo effect" used by the industry is obtained by rapid dilution from an identified "pre-Ouzo" domain of composition where weak aggregates are present: nanometer-sized clusters covered by a surface layer enriched in a hydrotrope such as ethanol. In these systems, Ostwald ripening is not an effective destabilizing mechanism. Using in situ autodilution small-angle X-ray scattering (SAXS), we follow the morphological transitions occurring in a ternary mixture of water/n-octanol/ethanol throughout the monophasic and biphasic regions. This allows for the first time an online characterization of the multiscale coexisting microstructures. Small-angle neutron scattering (SANS) profiles on metastable emulsions as well as phase-separated samples complete the SAXS data, taking advantage of contrast variation via isotopic substitution. After crossing the phase boundary into the two-phase region, coexisting phases are both ternary solutions structured at the nanometer scale when the emulsion is stable. The transition from single phase to two phases is asymmetric around the plait point. When the initial concentration of the hydrotrope is below the minimum hydrotrope concentration (MHC), emulsification failure occurs, i.e., emulsions cream within seconds. Beyond MHC, the low interfacial tension between coexisting ternary fluids results in a Laplace pressure below 100 Pa, explaining the puzzling resilience of spontaneous emulsion to the universal mechanism of Ostwald ripening.
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In this work, we developed a general theoretical description of ternary solutions of small molecules under a centrifugal field, from which we obtained the centrifugation map (CMap) as a general tool to understand observations or to... more
In this work, we developed a general theoretical description of ternary solutions of small molecules under a centrifugal field, from which we obtained the centrifugation map (CMap) as a general tool to understand observations or to predict composition profiles in centrifugal fields of arbitrary strength. The theoretical formalism is based on the classical density functional theory with established models for liquid mixtures. Thermodynamics also yields a general criterion for apparent aggregation. The strength of the CMap approach is illustrated for a ternary model system where ethanol is a co-solvent.
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Amongst the multitude of papers that report the phenomenological behavior of liquid–liquid extraction, a significant fraction are associated with the separation, purification, and recycling of metals (both for industrial metal production... more
Amongst the multitude of papers that report the phenomenological behavior of liquid–liquid extraction, a significant fraction are associated with the separation, purification, and recycling of metals (both for industrial metal production as well as energy portfolios – as in nuclear energy applications). Over the last decade, an exponential increase in publications has been supported by fundamental advances to the science of phase transfer in multiphase systems, which has evolved to include predictive capabilities that finally exceed rough apparent “stoichiometry” determinations. The trend was clearly articulated within the latest issue of the series edited by Bruce Moyer (Moyer, B. A., Ed. Changing the Landscape in Solvent Extraction. Ion Exchange and Solvent Extraction, A Series of Advances, Vol. 23, CRC Press: Philadelphia, PA, 2019.). There it was noted that, for carefully designed systems, distribution ratios can be directly related to the reaction free energy of transfer in a simple exact and unique formula. Further, any theory that predicts the energetic characteristics of phase transfer without fitting distribution ratios variation with temperature, mole ratios, solvent additives will help to design the separation processes of the future (Sholl, David S.; Lively, Ryan P. Seven chemical separations to change the world. Nature 2016, 532, 435–437.). In this special issue, we have assembled seven specially focused papers that emphasize the structure, function, and thermodynamic characteristics of the many interactions that contribute to this radically new approach toward the fundamental science of liquid–liquid phase transfer. Collectively, these works beautifully demonstrate how the organization and distribution of local and extended chemical environments at the interface and the organic phase can be used to re-interpret the traditional paradigms of liquid–liquid extraction. They also consolidate the simultaneous molecular, supramolecular and colloidal approach that moves towards predictive theories that are useful for the chemical engineer in charge of designing effective plants.
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Revisiting aggregation of extractant molecules into water-poor mixed reverse micelles, we propose in this paper to identify the thermodynamic origins of synergy in solvent extraction. Considering that synergistic extraction properties of... more
Revisiting aggregation of extractant molecules into water-poor mixed reverse micelles, we propose in this paper to identify the thermodynamic origins of synergy in solvent extraction. Considering that synergistic extraction properties of a mixture of extractants is related to synergistic aggregation of this mixture, we identify here the elements at the origin of synergy by independently investigating the effect of water, acid, and extracted cations. Thermodynamic equations are proposed to describe synergistic aggregation in the peculiar case of synergistic solvent extraction by evaluating critical aggregation concentration (CAC) as well as specific interactions between extractants due to the presence of water, acid and cations. Distribution of two extractant molecules in the free extractants and in reverse micelles was assessed, leading to an estimation of the in-plane interaction parameter between extractants in the aggregates as introduced by Bergström and Eriksson ( Bergström, M.; Eriksson, J. C. A Theoretical Analysis of Synergistic Effects in Mixed Surfactant Systems . Langmuir 2000 , 16 , 7173 - 7181 ). Based on this model, we study the N,N'-dimethyl-N,N'-dioctylhexylethoxymalonamide (DMDOHEMA) and di(2-ethylexyl) phosphoric acid (HDEHP) mixture and show that adding nitric acid enhances synergistic aggregation at the equimolar ratio of the two extractants and that this configuration can be related to a favored enthalpy of mixing.
Research Interests: Biochemistry, Chemistry, Plant Biology, Ecology, Space Science, and 12 moreMedicine, Multidisciplinary, Micelle, Enthalpy, EXTRACTION, CAC, Acid, Langmuir, Mixture, Molecule, Solvent, and Pulmonary Surfactant(Medicine, Multidisciplinary, Micelle, Enthalpy, EXTRACTION, CAC, Acid, Langmuir, Mixture, Molecule, Solvent, and Pulmonary Surfactant)
(Medicine, Multidisciplinary, Micelle, Enthalpy, EXTRACTION, CAC, Acid, Langmuir, Mixture, Molecule, Solvent, and Pulmonary Surfactant)
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Research Interests: Environmental Engineering, Civil Engineering, Environmental Science, Prediction, Simulation, and 15 moreFlow, Calibration, Evapotranspiration, Forests, Boundary Conditions, Soils, Sol, Trees, Transpiration, Hedge, Soil Water, Hydrological Processes, Field Studies, Unsaturated Zone, and Drainage Basins
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Here we present a series of complete phase prisms for water, an organic diluent and di-(2-ethylhexyl) phosphoric acid (HDEHP), one of the most widely used double-branched lipophilic surfactants in hydrometallurgy. Partial or total... more
Here we present a series of complete phase prisms for water, an organic diluent and di-(2-ethylhexyl) phosphoric acid (HDEHP), one of the most widely used double-branched lipophilic surfactants in hydrometallurgy. Partial or total titration with sodium hydroxide evidence that the mole fraction of the counter-cation “Z” is the variable that controls the packing and spontaneous curvature of the curved film formed by this extractant. Penetrating solvents such as toluene and iso-octane and the non-penetrating solvent dodecane as well as common hydrotropes acting as co-solvents, are considered. The three classical cuts of the phase prism are shown. The regions for which liquid–liquid extraction is possible are determined, as well as the location of the liquid crystals at the origin of the often observed third-phase formation. It is shown that profoundly different trends are obtained when replacing the common solvents currently used in hydrometallurgical processes with hydrotropes.
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The viscosity increase of the organic phase when liquid–liquid extraction processes are intensified causes difficulties for hydrometallurgical processes on industrial scale. In this work, we have analyzed this problem for the example of... more
The viscosity increase of the organic phase when liquid–liquid extraction processes are intensified causes difficulties for hydrometallurgical processes on industrial scale. In this work, we have analyzed this problem for the example of N,N-dialkylamides in the presence of uranyl nitrate experimentally. Furthermore, we present a minimal model at nanoscale that allows rationalizing the experimental phenomena by connecting the molecular, mesoscopic and macroscopic scale and that allows predicting qualitative trends in viscosity. This model opens broad possibilities in optimizing constraints and is a further step towards knowledge-based formulation of extracting microemulsions formed by microstructures with low connectivity, even at high load with heavy metals.
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Research Interests: Chemistry, Medicine, Multidisciplinary, Micelle, Microemulsion, and 15 moreMicelles, Cationic polymerization, Phase transition, Anions, Octane, Emulsions, Microchemistry, Surface Active Agents, Langmuir, Quaternary Ammonium Compounds, Cations, Phase Behavior, Pulmonary Surfactant, Octanes, and phase diagram
Research Interests: Engineering, Thermodynamics, Chemistry, Chemical Physics, Microemulsion, and 13 moreCurvature, Physical sciences, Free Energy, Temperature Dependence, CHEMICAL SCIENCES, Heat Capacity, Gaussian, Microstructures, Thermal Properties, Factor structure, Gaussian Curvature, Thermal Expansion, and Volume Fraction
There is a still growing interest in the recovery of rare earth elements due to their manifold industrial and technological applications. We present here a simple and effective method for the enrichment of micrometer sized La2O3 particles... more
There is a still growing interest in the recovery of rare earth elements due to their manifold industrial and technological applications. We present here a simple and effective method for the enrichment of micrometer sized La2O3 particles via microparticle stabilized foams. By using the short chain amphiphile (1-hexyl)trimethylammonium bromide (C6TAB) foam that is generated by surface modified particles only can be generated. This technique allows a more selective and specific particle transport mechanism. The