Performance and deactivation of Ir/γ-Al2O3 catalyst in the hydrogen peroxide monopropellant thruster Original Research Article

The performance of Ir/γ-Al2O3 catalyst for the decomposition of high concentration hydrogen peroxide was investigated in a monopropellant thruster. The changes of ignition delay (t0), chamber pressure (Pc) and catalyst bed temperature (Tc) with the numbers of startup–shutdown cycles were proved to be effective indicators of catalyst bed efficiency. The fresh catalyst and the deactivated catalyst were characterized with H2-TPR, XRD and XPS. It was found that catalyst oxidation and surface Sn poisoning are the major reasons of catalyst deactivation.