Microemulsion as model to predict free energy of transfer of electrolyte in solvent extraction - Université de Montpellier Accéder directement au contenu
Article Dans Une Revue Solvent Extraction and Ion Exchange Année : 2022

Microemulsion as model to predict free energy of transfer of electrolyte in solvent extraction

Résumé

We consider here the extraction of metals in the form of salts transferred from an aqueous to a solvent phase. Extraction is triggered by complexation and quenched by the associated necessary reorganization of the structured solvent phase. The extraction of ions changes the relative fraction of extractant molecules that is not part of the highly curved surfactant monolayer and is dispersed molecularly in the oil, and also the polar volume fraction including co-extracted water. The free energy and corresponding microstructures of the water-poor microemulsions are modelled in the frame of the Gaussian random fields (GRF) model. The curvature frustration energy significantly contributes to the free energy of extraction. A typical example of predicted isotherm using the GRF model is compared to the classically considered supramolecular complex formation, together with a minimal Langmuir model and an explicit monomer-to-film equilibrium of amphiphilic extractant. The corresponding small-angle scattering spectra and morphology changes are shown. One implication is that selectivity between a hydrated and a non-hydrated species is concentration dependent and cannot be considered as a constant as a function of the extractant concentration.
Fichier non déposé

Dates et versions

hal-03325952 , version 1 (25-08-2021)

Identifiants

Citer

Simon Gourdin-Bertin, Jean-François Dufrêche, Magali Duvail, Thomas Zemb. Microemulsion as model to predict free energy of transfer of electrolyte in solvent extraction. Solvent Extraction and Ion Exchange, 2022, 40 (1-2), pp.28-63. ⟨10.1080/07366299.2021.1953259⟩. ⟨hal-03325952⟩
50 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More