CATALYTIC IGNITION OF COLD HYDROGEN/OXYGEN MIXTURES FOR SPACE PROPULSION APPLICATIONS

An experimental bench test was conducted to evaluate the catalytic ignition of gaseous hydrogen and oxygen mixtures at low temperature by injection of cold gas mixtures on the catalytic microreactor. The selected supports for this study were cylindrical monoliths; i.e., cordierite honeycomb (600 channels per square inch) manufactured by CTI Company (Ceramiques & Techniques Industrielles). These materials were coated with porous γ-alumina to increase their specific surface area, and then impregnated by different metal precursors (Ir, Rh, Pt, and Ir−Rh). The premix gas reacted with the catalyst surface upon arrival in the combustion chamber. The first results led to a primary selection of different catalysts that allowed comparison with the different active phases. Based on the maximum temperature reached by the gas flow after a given time, we can sort the active phases as follows: Ir > Ir−Rh > Pt > Rh.