Parahydrogen-Orthohydrogen Catalytic Conversion for Cryogenic Propellant Passive Heat Shielding

The Hydrogen Properties for Energy Research (HYPER) laboratory at Washington State University (WSU) recently demonstrated a Cryocatalysis Hydrogen Experiment Facility (CHEF) to characterize parahydrogen-orthohydrogen catalysts for passive heat shielding. Current passive heat shields utilize boiloff vapors from liquid hydrogen (LH2) tanks to refrigerate and eliminate boiloff from liquid oxygen (LOX) tanks. Catalyzing the endothermic parahydrogen-orthohydrogen conversion is estimated to increase the refrigeration capacity of the hydrogen as much as 50% and effectively reduces the amount of hydrogen required to maintain zero boiloff of LOX. In this project, Ultramet will partner with the HYPER laboratory at WSU to synthesize, characterize, and compare ruthenium- and iron-based catalysts for optimal thermal properties and processing when applied to lightweight fiber blanket material for bulk application in passive heat shielding. In Phase I, a design matrix of catalysts will be characterized over a range of porosities and activities. Ultramet will perform surface area analysis of the catalyst granules prior to single-blind heat shielding tests in CHEF at the HYPER laboratory. In Phase II, the properties of the leading catalysts will be optimized for phase and porosity, the properties of the leading blanket material will be applied to a COMSOL modeling program already developed by the HYPER lab to design a prototype blanket, and a manufacturing plan will be developed. Potential Phase II and III teaming partners are United Launch Alliance (ULA) and Boeing, both of which have expressed interest in the technology.