Room-temperature catalytically reactive ammonium dinitramide-H2O2 monopropellant for microsatellites

Abstract

Room-temperature catalytically reactive ammonium dinitramide (ADN)-based green monopropellants are interesting for space applications, particularly for microthruster applications. In this study, a blend of ADN and 90-wt% hydrogen peroxide monopropellant was developed and its catalytic reactivity was investigated at different temperatures. An optimal ADN-hydrogen peroxide monopropellant (AHMP) was fabricated at a weight ratio of 40:60 wt:wt (ADN:90-wt% H2O2). The theoretical vacuum specific impulse of AHMP was 206 s, 20% higher than the specific impulse (172 s) of 90-wt% hydrogen peroxide. The thermal properties of AHMP were evaluated using thermogravimetric analysis-differential scanning calorimetry, which revealed that thermal behavior of AHMP containing ADN and 90wt% hydrogen peroxide was similar to their pure compound. The storability of AHMP was estimated using Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Notably, AHMP could be stored at low temperatures (2-3 degrees C) for 4 months and at room temperature (20-23 degrees C) for 1.4 months without chemical changes. Furthermore, drop test and microthruster test were performed to determine the reactivity of AHMP with a catalyst (Pt/La/Al2O3). The response time of the catalyst on the decomposition of AHMP was approximately 104.6, 24.8, and 7.0 ms at 23, 60, and 120 degrees C, respectively. This study on the AHMP green monopropellant paves the way for further studies on improved ADN-hydrogen-peroxide-based monopropellants for microthruster applications. (c) 2021 COSPAR. Published by Elsevier B.V. All rights reserved.