Titre :

Effect of the alkyl chain and composition on the thermodynamics of mixing of small alcohols and water

Auteur(s) :

Idrissi, Nacer [Auteur]
Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement (LASIRE) - UMR 8516
Jedlovszky, P. [Auteur]

Titre de la revue :

Journal of Molecular Liquids

Nom court de la revue :

J. Mol. Liq.

Numéro :

338

Pagination :

-

Date de publication :

2021-09-09

ISSN :

0167-7322

Mot(s)-clé(s) en anglais :

Thermodynamic integration
Computer simulation
Thermodynamics of mixing
Alcohol-water mixtures

Discipline(s) HAL :

Chimie/Chimie théorique et/ou physique

Résumé en anglais : [en]

The thermodynamic changes occurring upon mixing small monovalent alcohols and water are systematically analyzed as a function of both the size and shape of the apolar group of the alcohols and of the mixture composition. ...
Lire la suite >The thermodynamic changes occurring upon mixing small monovalent alcohols and water are systematically analyzed as a function of both the size and shape of the apolar group of the alcohols and of the mixture composition. For this purpose, the Helmholtz free energy, energy and entropy of mixing of the eight smallest alcohols, i.e., methanol, ethanol, propanol, isopropanol, butanol, isobutanol, s-butanol, and t-butanol with water are calculated in the entire composition range by means of Monte Carlo simulations and thermodynamic integration with three different model combinations. The obtained results are in a satisfactory agreement with existing experimental data. In particular, they are able to well reproduce the qualitative trends, being in the focus of this study. Our results indicate that the thermodynamics of mixing of these systems is primarily governed by the entropic term. In particular, the addition of alcohol to water-rich systems induces an ordering of the water molecules through hydrophobic hydration, while the addition of water to alcohol-rich mixtures induces ordering of the alcohol molecules by providing them additional H-bonds. According to the obtained free energy of mixing data, the former of these two effects clearly becomes more pronounced with increasing size and decreasing branching (i.e., increasing surface area) of the apolar groups, while the latter one is much less sensitive to the apolar tail. As a consequence, the increase of the apolar tail (and the decrease of its branching) leads to partial miscibility of the alcohols with water, with a miscibility gap occurring in water-rich compositions.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
CNRS

Collections :

• Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement (LASIRE) - UMR 8516

Date de dépôt :

2024-02-28T23:34:15Z
2024-03-15T10:31:38Z