Determination and Correlation of Solubility of 1,2-Difluoro-4,5-dinitrobenzene in 16 Pure Solvents at Temperatures Ranging from 293.15 to 333.1 5 K

Abstract

The purity of 1,2-difluoro-4,5-dinitrobenzene (DFDNB), as an important carrier for insensitive melt cast explosives, directly affects its performance. However, there are currently no reports on the solubility of DFDNB. Given the importance of solubility data for its purification process, this study used a laser dynamic method to systematically determine the solubility of DFDNB in 16 pure solvents within a temperature range of 293.15–333.15 K. To expand the application scope of the data, the experimental data were correlated using the Apelblat equation, Yaws model, van’t Hoff equation, polynomial empirical equation, and nonrandom two-liquid (NRTL) model. The fitting results indicate that all models exhibit good accuracy, with an average R² value greater than 0.99 and root-mean-square deviation (RMSD) close to zero. The RMSD ranking of each model is van’t Hoff eq (0.0130) > NRTL model (0.0071) > Apelblat equation (0.0041) > Yaws model (0.0039) > polynomial empirical eq (0.0019), and the order of R² is polynomial empirical equation (0.9997) > Apelblat equation (0.9993) = Yaws model (0.9993) > NRTL equation (0.9971) > van’t Hoff equation (0.9949). Based on the comprehensive RMSD and R² evaluation indicators, the polynomial empirical equation shows the best fitting effect. This study provides important basic solubility data for the optimization of the purification process, screening of crystallization conditions, and industrial application of DFDNB.