Collaborations: Pr. L. Arleth (University of Copenhagen, Danemark), Dr. S. Marcelja (Australian National University, Canberra)
The mesoscopic modelling of the microemulsion (water / oil / surfactant) thermodynamics properties is crucial to understand the phenomena occuring during the liquid-liquid extraction process (mainly used for the ions separation).
The mains objectives of this study are :
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Collaborations: Dr. Ph. Guilbaud (CEA), Pr. J.-F. Dufrêche (ICSM), Dr. J. J. Molina (PECSA and ICSM), Dr. T. N. Nguyen (ICSM), M. Bley (ICSM), M. Coquil (CEA), Dr. S. van Damme (ICSM), Dr. Y. Chen (ICSM)
Binary solutions of lanthanoids and uranyl (UO22+) salts (ClO4−, Cl−, NO3−) at different concentrations are studied by means of classical molecular dynamics simulations using explicit polarization. Dissociation / association processes of ion pairs in aqueous solution are analyzed using potential of mean force (PMF) profile calculations.
Thanks to the calculations of the McMillan-Mayer potentials, ion pair association constants are also calculated. Activity coefficients are also determined using an Associated Mean Spherical Approximation (AMSA) approach.
Molecular dynamics simulations of lanthanoid in organic phases (alcohol and alkane) are performed to understand the solvation properties of such cations. We also focus on the thermodynamics properties of micelles composed of ions, water and extractant molecules in apolar solvents (such as alkanes), and especially their curvature free energies. These preliminary simulations pave the way for further structural studies in organic solvents: anion coordination, association / complexation with ligands (monoamide, diamide, nitrogen ligands, ...), and therefore may improve the understanding of ion speciation in organic phases.
Collaborations: Dr. A. Poulesquen (CEA), Dr. D. Petit (L2C, University Montpellier), J. Lind (Woellner GmbH & Co.KG, Germany), A. Coste (ICSM)
Projet : ANR DYNAMISTE ANR-15-CE07-0013-01
DYNAMISTE aims at developing experimental and theoretical tools in order to optimize industrial processes in which alkali solutions of aluminosilicates are involved in an attempt of developing sustainable and clean industry. This project gathers the expertise of ICSM, a CEA department for the waste retreatment and conditioning and specialist for the characterization and formulation of cement-based materials, and a CNRS team at the Laboratoire Charles Coulomb expert in multi-scale NMR technics, in collaboration with the German industrial partner Wo?llner GmbH & Co.KG, who is one of the leaders in production of alkali silicate solutions.
This project relies on a synergic approach coupling both experiments and modeling. In order to access all the spatio-temporal phenomena of such systems, the experimental part consists in studies based on (i) rheology techniques coupled with scattering techniques: Dynamic light scattering (DLS), small and wide angle x-ray and (or) neutron scattering and diffraction (SWAXS, SANS and XRD), and on (ii) multi-scale NMRapproaches (from Å to few tens μm). In the meantime, the theoretical part is based on multi-scale methods coupling molecular dynamics and coarse-grained simulations, allowing for accessing the structural and dynamical properties of these fluids at both the molecular and supramolecular scales.