Thermal Decomposition of Ammonium Dinitramide Vapor in a Two-Temperature Flow Reactor

Abstract

The thermal decomposition of ammonium dinitramide (ADN) was studied using a two-temperature flow reactor. The vapor pressure at temperatures of 80-140°C and the heat of vaporization of ADN were determined. From the results obtained a mechanism for the thermal decomposition of ADN was proposed that includes the ADN vaporization stage, i.e., the transition from the condensed to the gaseous state in the form of the molecular complex NH$3·HN(NO2)2 (ADN vapor) followed by dissociation into NH3 and HN(NO2)2. The composition of the products from the thermal decomposition of ADN vapor at temperatures of 160–900°C was determined by mass spectrometry. The effective rate constant was determined for the dissociation of ADN vapor at temperatures of 160–320°C. The thermal decomposition of ADN vapor in a flow reactor was modeled using the proposed mechanism and the reaction rate constant for ADN vapor dissociation. Key words: ammonium dinitramide, dinitramide, molecular beam mass spectrometry, thermal decomposition, two-temperature flow reactor.