Study on the dissolution behaviors of CL-20/TNT co-crystal in N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO)

2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (cl-20)/2,4,6-trinitrotoluene (tnt) co-crystal in 1:1 molar ratio was prepared by a solvent evaporation method, and the structural characterizations of cl-20/tnt co-crystal were systematically investigated by powder x-ray diffraction, raman and differential scanning calorimeter. the dissolution behaviors of cl-20/tnt co-crystal in n,n-dimethylformamide (dmf) and dimethyl sulfoxide (dmso) were investigated by a dc08-1 calvet microcalorimeter at 298.15 k, showing that the dissolution processes were all exothermic. the heat effects (q) of cl-20/tnt co-crystal dissolved in dmf and dmso both increased with the increase of the amount of co-crystal. empirical formulas for the calculation of the enthalpies of dissolution ((delta _{text{diss}} h)), relative apparent molar enthalpies ((delta _{text{diss}} h_{text{apparent}})), relative partial molar enthalpies ((delta _{text{diss}} h_{text{partial}})) were obtained from the experimental data of cl-20/tnt co-crystal dissolved in dmf and dmso. it was found that the values of (delta _{text{diss}} h), (delta _{text{diss}} h_{text{apparent}}) and (delta _{text{diss}} h_{text{partial}}) were affected by the molality of co-crystal (b). the kinetic equations describing the dissolution of cl-20/tnt co-crystal in dmf and dmso at 298.15 k are ({text{d}}alpha / {text{d}}t = 10^{ - 2.39} left( {1 - alpha } right)^{0.89}) and ({text{d}}alpha / {text{d}}t = 10^{ - 2.47} left( {1 - alpha } right)^{0.62}), respectively.