Solid-liquid equilibrium of forchlorfenuron in four binary solvents: Experiments, hansen solubility parameter and molecular simulation

In this research, the solubility of forchlorfenuron in 4 binary solvent systems {(methanol, ethanol, n-propanol and acetone) + water} was determined at certain experimental conditions (pressure of 101.3 kPa, temperature of 278.15 K-323.15 K) using laser dynamic monitoring method. Five thermodynamic models were applied to correlate and analyze the experimentally measured data. The modified Apelblat model has the lowest value of ARD (100 ARD  = 2.046 %) indicates that it fits best. The apparent thermodynamic properties during the dissolution process of forchlorfenuron in the four mixed solvent systems were explored using Van't Hoff equation. The effect of solvent properties on the dissolution was explored by calculating Hansen solubility parameters. For further understanding the solubility behavior on the molecular scale, molecular electrostatic potential analysis and Hirshfeld surface analysis were conducted to visualize the molecular surface charge distribution and predict the contact behavior between forchlorfenuron and solvent. Finally, the influence of intermolecular interactions between solute and solvent on solubility behavior was explored using radial distribution function analysis based on molecular dynamics simulations. And the results show the stronger intermolecular force corresponds to the larger solubility.