Solubility measurement, Hansen solubility parameter, molecular dynamic simulation and thermodynamic properties of 2-ethoxy-1-naphthoic acid in three binary solvents at 278.15–323.15 K

• The solubility of 2-ethoxy-1-naphthoic acid in three binary solvents were determined. • Experimental solubility data were correlated by five different models. • Hansen solubility parameter was applied to analyze the solubility behavior. • RDF analysis explores the impact of interactions. • Thermodynamic properties of the solution were calculated and discussed. The solubility behavior of 2-ethoxy-1-naphthoic acid (ENCA) in binary solvents is critical for its purification and application in pharmaceuticals and advanced materials. This study systematically investigates the solubility of ENCA in three binary solvents (methanol + water, ethanol + water, and n-propanol + water) at atmospheric pressure within the temperature range of 278.15 K–323.15 K using the gravimetric method. The results demonstrated that the solubility of ENCA exhibited a positive dependence on both temperature and the mass fraction of the alcohol component in all solvents, albeit with distinct sensitivity trends across the three binary solvent systems. Among five thermodynamic models evaluated, the modified Apelblat equation provided the most accurate predictions ( ARD < 8 %). Thermodynamic analysis confirmed the dissolution process is endothermic and entropy-driven, with enthalpy contributions dominating the Gibbs free energy change (Δ sol G °). Molecular dynamics simulations and Hansen solubility parameters further elucidated that hydrogen bonding and electrostatic interactions between ENCA’s polar groups and solvent molecules govern solubility trends. These findings offer fundamental insights into ENCA’s solvation mechanisms and practical guidance for optimizing its crystallization processes in industrial applications.