Solubility, modelling, preferential solvation and solvent effect of 2-amino-6-chloropyrazine in ten pure mono-solvents and four solvent mixtures at 278.15 K to 323.15 K

• Published in: The Journal of chemical thermodynamics 2023-10, Vol.185, p.107109, Article 107109
• Main Authors: Li, Zhenghui, Shen, Yue, Huang, Chunjuan
• Format: Article
• Language: English
• Subjects: 2-Amino-6-chloropyrazine; Modelling; Preferential solvation; Solubility; Solvent effect
• ISSN: 0021-9614; 1096-3626
• DOI: 10.1016/j.jct.2023.107109

[Display omitted] •The solubility of 2-amino-6-chloropyrazine in different solvents were determined.•The solubility data were calculated by different thermodynamic models.•Apparent thermodynamic properties were obtained by van’t Hoff plots.•Preferential solvation of 2-amino-6-chloropyrazine was investigated by IKBI method.•The solvent effect of 2-amino-6-chloropyrazine was analyzed by KAT-LSER model. Equilibrium solubility of 2-amino-6-chloropyrazine in ten pure solvents (methanol, ethanol, n-propanol, isopropanol, N,N-Dimethylformamide (DMF), acetonitrile, acetone, propylene glycol (PG), ethylene glycol (EG) and water) and four binary blends of ethanol/n-propanol/PG/DMF plus water was experimentally measured by isothermal saturation method at 278.15 K to 323.15 K under p = 101.2 kPa. The maximum mole fraction of 2-amino-6-chloropyrazine in mono-solvents was obtained in neat acetone (5.053 × 10-2) at 323.15 K. For four binary mixed systems, the amount of 2-amino-6-chloropyrazine dissolved in DMF + water was more than other three systems. For pure solvent systems, the temperature was the only factor that affected the dissolution of 2-amino-6-chloropyrazine, while temperature and solvent composition were both the factors that affected the dissolution of 2-amino-6-chloropyrazine. The solubility data of 2-amino-6-chloropyrazine in pure solvents was correlated with apelblat model, van’t Hoff model and Buchowski–Książczak λh model. The Jouyban-Acree model, Apelblat-Jouyban-Acree model and van’t Hoff-Jouyban-Acree model were applied to calculate the solubility data of 2-amino-6-chloropyrazine in mixtures. The van’t Hoff plots of the solubility of 2-amino-6-chloropyrazine was adopted as a method to show the relationship between ln × and 1/T-1/Thm, which was the basis for calculating thermodynamic properties. The preferential solvation performance in mixed systems was estimated by the values of δx1,3, in 0.19