Kinetics of Thermal Decomposition of Solid Propellant Based on Aluminum and Ammonium Perchlorate

• Published in: Russian journal of applied chemistry 2019-11, Vol.92 (11), p.1558-1569
• Main Authors: Volkova, N. N., Dubovitskii, V. A., Zholudev, A. F., Zaslavskii, G. E., Kazakov, A. I., Kislov, M. B., Nabatova, A. V., Puchkovskii, I. V., Yanovskii, L. S.
• Format: Article
• Language: English
• Subjects: Aluminum; Ammonium perchlorates; Autocatalysis; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Decomposition; Distribution functions; Evacuation systems; Heat; Heating rate; High Energy Materials; High temperature effects; Ignition; Industrial Chemistry/Chemical Engineering; Kinetics; Process parameters; Propellant decomposition; Rate constants; Reaction kinetics; Solid propellants; Thermal decomposition; Time dependence
• ISSN: 1070-4272; 1608-3296
• DOI: 10.1134/S1070427219110132

Kinetic regularities of the mass loss and heat and-gas release were studied in the thermal decomposition of a solid propellant composed of aluminum, ammonium perchlorate, and a polymer binder. It was shown that, under heating from 40 to 340°C under permanent vacuum conditions, propellant samples decompose without ignition, with the limiting mass loss in the decomposition being 48%. When experiments were performed in air, the propellant formulation decomposes with sharp ignition, with the inflammation temperature (270–287°C) and amount of volatiles released by this instant of time (10–16 wt %) dependent on the heating rate. The kinetic regularities of the mass loss in the decomposition of a solid propellant were described in terms of the polychromatic kinetics model that assumes that the reaction system has ensembles of particles differing in reactivity. The distribution functions of the mass fractions of the propellant by activation energies of decomposition were calculated. The heat release kinetics in the decomposition of a propellant formulation in the temperature range 153–270°C in a closed evacuated system is described by a sum of equations for two parallel reactions: 1st-order reaction with a heat effect Q 1 = 200 ± 5 kJ kg –1 and 1st-order autocatalysis with heat effect Q 2 = 1900 ± 50 kJ kg–1. The rate constants and the activation parameters of the process were determined.