Solubility, thermodynamics, and preferential solvation of 3-Nitrobenzaldehyde in Binary Ethanol/Ethyl Acetate and 1-Propanol/Ethyl acetate solvent mixtures

This study examines the solubility and thermodynamic behavior of 3-nitrobenzaldehyde (3-NBA) in ethanol (EtOH), 1-propanol (1-PrOH), ethyl acetate (EA), and two binary solvent mixtures (EtOH + EA, 1-PrOH + EA). Solubility was measured using a gravimetric method and analyzed with four co-solvency models at temperatures ranging from 278.15 to 303.15 K, all showing strong predictive accuracy. Results revealed a non-monotonic solubility trend and indicated that 3-NBA dissolution is endothermic and spontaneous until the saturation point is reached. The thermodynamic properties of the mixtures were calculated using van't Hoff and Gibbs equations. Preferential solvation behavior in mixed solvents was evaluated using the IKBI method, showing a stronger affinity of 3-NBA for EA, especially in EtOH-based mixtures.