Thermodynamics and solubilization behavior of (2Z)-N-cyclohexyl-2-(3-hydroxybenzylidine) hydrazine carbothioamide in polyethylene glycol-400 + water mixtures at (298.15 to 338.15) K

Abstract

Dissolution thermodynamics of (2Z)-N-cyclohexyl-2-(3-hydroxybenzylidine) hydrazine carbothioamide (CHBH) in various polyethylene glycol-400 (PEG-400)+water mixtures from (298.15 to 338.15)K were studied and correlated. The experimental solubilities were correlated with the modified Apelblat and Yalkowsky models. The root mean square deviations (RMSD) were observed as (0.88–4.28)% for the modified Apelblat model and (2.10–8.25)% for Yalkowsky model. The mole fraction solubility (7.12×10−2 at 298.15K) and mass fraction solubility (5.32×10−2kgkg−1 at 298.15K) of CHBH were observed highest in pure PEG-400. However, the lowest mole fraction (3.83×10−7 at 298.15K) and mass fraction solubility (5.90×10−6kgkg−1 at 298.15K) of CHBH were observed in pure water. Thermodynamic studies showed endothermic and spontaneous dissolution of CHBH in all co-solvent mixtures.