Dissolution thermokinetics of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate in dimethyl sulfoxide

The enthalpies of dissolution for dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) in dimethyl sulfoxide were measured using a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. Differential enthalpies (Δ dif H ) and molar enthalpies (Δ diss H ) of dissolution were determined. Furthermore, the corresponding kinetic equations describing the dissolution processes at the four experimental temperatures are d α /d t = 10 −2.60 (1 − α ) 1.01 ( T = 298.15 K), d α /d t = 10 −2.59 (1 − α) 0.93 ( T = 303.15 K), d α /d t = 10 −2.58 (1 − α ) 1.36 ( T = 308.15 K), d α /d t = 10 −2.57 (1 − α ) 1.21 ( T = 313.15 K). The determined values of the activation energy E and pre-exponential factor A for the dissolution process are 3.24 kJ mol −1 and 10 −2.03 s −1 , respectively.