Physicochemical characterization and simulation of the solid-liquid equilibrium phase diagram of terpene-based eutectic solvent systems

The characterization of terpene-based eutectic solvent systems is performed to describe their solid–liquid phase transitions. Physical properties are measured experimentally and compared to computed correlations for deep eutectic solvents (DES) and the percentage relative error er for the density, surface tension, and refractive index is obtained. The thermodynamic parameters, including the degradation, glass transition and crystallization temperatures, are measured using DSC and TGA. Based on these data, the solid–liquid equilibrium phase diagrams are calculated for the ideal case and predictions are made using the semi-predictive UNIFAC and the predictive COSMO RS models, the latter with two different parametrization levels. For each system, the ideal, experimental, and predicted eutectic points are obtained. The deviation from ideality is observed experimentally and using the thermodynamic models for Thymol:Borneol and Thymol:Camphor. In contrast, a negative deviation is observed only experimentally for Menthol:Borneol and Menthol:Camphor. Moreover, the chemical interactions are analyzed using FTIR and1H-NMR to study the intermolecular hydrogen bonding in the systems.

Subjects

deep eutectic solvents

terpenes

physical characterization

simulation

equilibrium phase diagram

chemical interactions

DDC Class

540: Chemie

Funding Organisations

Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior

Publication version

publishedVersion

Lizenz

https://creativecommons.org/licenses/by/4.0/

Name

molecules-26-01801-v2.pdf

Size

1.91 MB

Format

Adobe PDF

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Physicochemical characterization and simulation of the solid-liquid equilibrium phase diagram of terpene-based eutectic solvent systems