Thermochemical properties of 2-oxo-1,3,5-trinitro-1,3,5-triazacyclohexane in dimethyl sulfoxide.

The dissolution properties of 2-oxo-1,3,5-trinitro-1,3,5-triazacyclohexane (Keto-RDX) in dimethyl sulfoxide (DMSO) were studied by using a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. The heat effects, molar enthalpies (<italic>Δ</italic>diss<italic>H</italic>), and differential enthalpies (<italic>Δ</italic>dif<italic>H</italic>) of dissolution were determined. Furthermore, the corresponding kinetic equations describing the dissolution processes at the four experimental temperatures are d<italic>α</italic>/d<italic>t</italic> = 10−2.43 (1 − <italic>α</italic>)0.63 (<italic>T</italic> = 298.15 K), d<italic>α</italic>/d<italic>t</italic> = 10−2.41 (1 − <italic>α</italic>)0.67 (<italic>T</italic> = 303.15 K), d<italic>α</italic>/d<italic>t</italic> = 10−2.40 (1 − <italic>α</italic>)0.75 (<italic>T</italic> = 308.15 K), and d<italic>α</italic>/d<italic>t</italic> = 10−2.38 (1 − <italic>α</italic>)0.76 (<italic>T</italic> = 313.15 K). The determined values of the activation energy <italic>E</italic> and pre-exponential factor <italic>A</italic> for the dissolution process are 5.99 kJ mol−1 and 10−1.38 s−1, respectively. [ABSTRACT FROM AUTHOR]