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• Solubility of 2,3-dichloropyridine in 14 pure solvents were measured. • Solubility modeling was realized by seven thermodynamic models. • Hansen solubility parameters were employed to explain solubility behaviors. • Solvent effect was studied by MEPs, Hirshfeld surface analysis and DFT calculation. • Thermodynamic properties were discussed by Van't Hoff equation. The solid–liquid equilibrium data of 2,3-dichloropyridine(23DCP) in 14 pure solvents were measured making use of the laser dynamic monitoring at 278.15/283.15/288.15 K − 313.15 K with 0.1 MPa. The findings of this study showed that the solubility increase of 23DCP in 14 pure solvents had a positive relation with temperature, and the solubility order was 1,4-dioxane > dichloromethane > n-butyl acetate > ethyl acetate > methyl acetate > acetonitrile > n-butanol > isobutyl alcohol > n-propanol > isopropanol > ethanol > cyclohexane > methanol > n-hexane. The solubility data of 23DCP was operated by seven models (Van't Hoff, modified Apelblat, λh, Yaws, NRTL, NRTL-SAC, Wilson) to correlate. And the average ARD values were 1.684 %,1.058 %, 1.031 %, 0.905 %, 0.937 %, 1.012 %, 2.062 % and the average 103RMSD values were 1.978, 1.396, 1.542, 1.221, 1.758, 1.658 and 1.883, respectively. In addition, Hansen solubility parameters were well evaluated to appraise the miscibility of 23DCP in 14 pure solvents. And the interactions between molecules were studied by means of molecular electrostatic potential surface, Hirshfeld surface analysis and density functional theory calculation. Finally, according to Van't Hoff equation, Δ sol G °, Δ sol H ° and Δ sol S ° of 23DCP in 14 pure solvents were got. Δ sol H ° and Δ sol S ° were bigger than zero, representing that this was a dissolution process of endothermic and entropy increase. [ABSTRACT FROM AUTHOR]

• Solubility data of 1,4-cyclohexanedione in ten pure solvents were measured. • Experimental data were correlated by five thermodynamic models. • Dissolution mechanism of 1,4-cyclohexanedione in ten pure solvents was investigated. • Thermodynamic properties were discussed by Wilson model. As an important raw material in industrial production, the solubility studies of 1,4-cyclohexanedione (14CHD) in organic solvents may be of assistance in improving crystallization efficiency and yield in industry. Therefore, this work deeply explored the dissolution behavior of 14CHD by using the isothermal saturation method, model fitting and density functional theory (DFT) calculation. Firstly, we selected ten pure organic solvents that are environmentally friendly to measure the solubility of 14CHD at the temperature range of 278.15 ∼ 313.15 K under standard atmospheric pressure. According to the measurement results, the solubility of 14CHD increases with temperature, and there are some differences among the solubility of 14CHD in various solvents. For instance, it has a highest solubility in acetonitrile (x 1 = 0.5331) at 313.15 K while has the lowest solubility (x 1 = 6.757 × 10-4) in cyclohexane at 283.15 K. Whereafter, the measured solubility data was correlated by Van't Hoff equation, modified Apelblat equation, λh model, Yaws model and Wilson model. Among them, Yaws model represents the most accurate fitting outcomes. At the same time, the study results of mixing thermodynamic properties on the basis of Wilson model suggest that the dissolution processes of 14CHD in ten organic solvents are entropy-driven and spontaneous. Afterwards, in order to explain the large difference in solubility of 14CHD in ten organic solvents, we found that the dissolution of 14CHD depends mostly on the polarity (π) and cohesive energy density (CED), viewed from the physicochemical factors of solvents. Furthermore, we further studied intermolecular interactions between 14CHD and ten solvents through molecular electrostatic potential surface (MEPS) analysis and DFT methods. Results display that alcoholic and non-alcoholic solvents molecules have different sites of action with 14CHD and the absolute values orders of interaction energies of alcoholic and non-alcoholic solvents are all consistent with corresponding solubility laws. The solvent–solute interaction plays an important role in the solubilities of 14CHD. [ABSTRACT FROM AUTHOR]