Synthesis and Thermal Behavior of 1,8-Dihydroxy- 4,5-dinitroanthraquinone Manganese Salt

A novel energetic combustion catalyst, 1,8-dihydroxy-4,5-dinitroanthraquinone manganese salt (DHDNEMn), was synthesized by virtue of the metathesis reaction in a yield of 91%, and its structure was characterized by IR, element analysis and differential scanning calorimetry(DSC). The thermal decomposition reaction kine-tics was studied by means of different heating rate DSC. The results show that the apparent activation energy and pre-exponential factor of the exothermic decomposition reaction of DHDNEMn obtained by Kissinger's method are 162.3 kJ/mol and (1011.8 s^-1, respectively. The kinetic equation of major exothermic decomposition reaction of DHDNEMn is da/dt=10^11.8/β)(2/5)(1-α)-in(1-α)]^3/5exp(-1.623×10⁵/RT). The entropy of activation(ΔS^≠), enthalpy of activation(ΔH^≠) and free energy of activation(ΔG^≠) of the first thermal decomposition are -24.49 J·mol^-1·K^-1, 185.20 kJ/mol and 199.29 kJ/mol(T=575.5 K), respectively. The self-accelerating decomposition temperature(T_SADT) and critical temperature of thermal explosion(T_b) are 562.9 and 580.0 K, respectively. The above-mentioned information on the thermal behavior is quite useful for analyzing and evaluating the stability and thermal safety of DHDNEMn.