Determining the kinetics of desolvation of a TNT/aniline solvate

Abstract

Desolvation of a TNT/aniline solvate was investigated using various experimental techniques by isothermal and non-isothermal methods. Conventional kinetic thermal analysis techniques (differential scanning calorimetry, thermogravimetry and atomic force microscopy) were used to study the kinetics during desolvation. The results indicate that the transition involves two steps, transformation into an amorphous or glassy state, and reconstruction of crystalline TNT by nucleation and growth. Isothermal powder X-ray diffraction studies revealed that different polymorphs of TNT were recrystallized during the desolvation process depending on the temperature. The kinetic parameters for desolvation and recrystallization processes were obtained and discussed. From the DSC and AFM results, the activation energies for these two processes were calculated to be 86.0 kJ mol⁻¹ and 22.8 kJ mol⁻¹, respectively.