The Single-Parameter Bragg-Williams Model for Eutectic Solvents

The study of solid-liquid equilibria offers critical insights into the molecular interactions between constituents in binary mixtures. Predicting these equilibria often requires comprehensive thermodynamic models, yet simplified approaches can provide valuable perspectives. In this work, we explore the application of the Bragg-Williams model to solid-liquid equilibria in binary mixtures leading to the formation of eutectic solvents. This model relies on a single parameter-the molar energy change upon mixing compounds-and demonstrates noteworthy features: the parameter can be estimated from a few (in principle, from a single) experimental melting points, and it correlates strongly with interaction energy parameters from more complex models, such as the PC-SAFT molecular-based equation of state. By using the Bragg-Williams model, we provide a straightforward and informative framework for characterizing solid-liquid equilibria, enabling insights into molecular interactions while requiring few data points as input. Despite its simplicity, the model effectively captures the essence of binary mixture energetics, positioning it as a practical tool for advancing the understanding of phase behavior in eutectic solvent systems.