Ir-Ru/Al2O3 catalysts used in satellite propulsion

Abstract

Ir/Al2O3, Ir-Ru/Al2O3 and Ru/Al2O3, catalysts with total metal contents of 30% were prepared using the methods of incipient wetness and incipient coimpregnation wetness and were tested in a 2N microthruster. Their performances were then compared with that of the Shell 405 commercial catalyst (30% Ir/Al2O3). Tests were performed in continuous and pulsed regimes, where there are steep temperature and pressure gradients, from ambient values up to 650 ºC and 14 bar. Performance stability, thrust produced, temperature and stagnation pressure in the chamber and losses of mass were analyzed and compared to the corresponding parameters in Shell 405 tests. It was observed that the performance of all the above-mentioned catalysts was comparable to that of the commercial one, except for in loss of mass, where the values was higher, which was attributed to the lower mechanical resistance of the support

Ir Impregnation on Alumina Pores: Catalyst Activity and Loss During Hydrazine Decomposition

“…Many investigations have focused on the decomposition of hydrazine over Ir/γ-Al 2 O 3 catalysts [21][22][23][24][25][26][27][28] suggesting that it is the most attractive catalyst choice for hydrazine decomposition in space thruster applications. Some ambi-guities, however, still remain due to the complex phenomena occurring during the reaction within the catalyst pellets.…”

An Open-source Solver to Model the Catalytic Decomposition of Monopropellants for Space Thrusters

“…1. Decomposition of the monopropellant occurs in the catalytic chamber, which, by its turn, is composed of a catalytic bed with porous catalyst particles (grains or pellets) (Jang et al 2012;Soares Neto et al 2003;Vieira et al 2005). The exhaust gases are expanded in the thrust chamber, generating thrust.…”

Catalisadores de Ir-Ru/Al2O3 e Ru/Al2O3 aplicados em sistemas propulsores

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