A. Villard

Specific effects of ions and hydrophilic/hydrophobic interactions

Supervisor: Pr. J-F. Dufrêche
Collaborations: A. Grandjean (ICSM/LNER)

This Ph.D. thesis aims at modelling the specific effects of ions, i.e. determining the origin of their different behaviours. To this end, a molecular approach is used, which allows for linking their thermodynamics properties to the concept of hydrophilicity/hydrophobicity generally used for solid surfaces. For this work, we take into account the microscopic aspects, that are often ignored, such as the ion and solvent polarisation, the depletion originated in the size of the hydrated particles, the screening modification coming from the size of ions, etc. Recently, many studies have explained some of these phenomena such as the specific attraction of ions having a similar size.

In collaboration with ICSM/LNER, we will first look at the selectivity of alkaline-earth ions for some new titanate (titanium oxides) materials, these materials being used to decontaminate liquid effluents. Extraction isotherms for divalent ions in aqueous solution will be calculated using the Mean Spherical Approximation (MSA) model. Concerning the solid phase, the two-dimensional classical electron gas model will used.