Determination andCorrelation of Solubility of Chlorothalonilin 10 Pure Solvents and One Binary Solvent at 288.15–323.15K

Chlorothalonil is a kind of high efficiency, low toxicity, and broad-spectrum fungicide pesticide, which is widely used in the prevention and control of plant fungal diseases. In this work, the solubility of chlorothalonil in 10 pure solvents and one binary solvent was determined by the gravimetric method at temperatures from 288.15 to 323.15 K. Ten experimental pure solvents were 1,4-dioxane, <i>N</i>,<i>N</i>-dimethylacetamide, acetone, cyclohexanone, acetonitrile, <i>N</i>,<i>N</i>-dimethylformamide, methyl isobutyl ketone, ethyl acetate, <i>n</i>-propyl acetate, and tetrahydrofuran. The selected binary solvent mixtures were <i>N</i>,<i>N</i>-dimethylacetamide and ethyl acetate in different proportions. The obtained data show that the solubility of chlorothalonil in the above solvents increases with the increase in temperature, and the solubility also increases with the increase in the <i>N</i>,<i>N</i>-dimethylacetamide ratio in the binary solvent. Furthermore, the experimental solubility data is well correlated by using the modified Apelblat model, Van’t Hoff model, modified Jouyban–Acree model, and Yaws model. The modified Apelblat model shows the best correlation with the solubility of chlorothalonil. In addition, the KAT-LSER model is used to investigate the influence of the solvent effect on the solubility, indicating that the solubility of chlorothalonil is negatively correlated with the polarity of the solvent.