Endurance Testing of Microlith® Catalytic Oxidizer for Exploration Trace Contaminant Control

Precision Combustion, Inc. (PCI) and NASA Marshall Space Flight Center (MSFC) have been developing and testing high-temperature catalytic oxidizers (HTCO) based on PCI’s patented Microlith® technology to meet the requirements of future spaceflight exploration missions. Multiple prototype units have been delivered to MSFC as part of continuous and iterative development process. These units have demonstrated benefits over competing technologies, including lower mass, lower volume, and reduced power consumption. The β-HTCO prototype was subjected to endurance testing (24,000+ hours) at MSFC to simulate catalyst ageing over a Mars transit mission duration. The end-of-life contaminant destruction efficiency was above the target metric of ≥90%. Microlith HTCO catalyst also demonstrated tolerance and recoverable performance after exposure to contaminants passed from the upstream guard bed. This feature could be utilized to monitor the health of the upstream guard bed and guide the maintenance schedule. The endurance testing, which included periodic reactor health testing, indicates that our approach results in a robust contaminant control solution for exploration missions beyond low earth orbit. Based on the β-HTCO test data, we designed a flight compatible, lightweight γ-LW HTCO that outperformed the traditional ISS HTCO unit with respect to volumetric and gravimetric density. PCI’s γ-LW HTCO prototype was delivered to MSFC and is currently being integrated with other exploration-compatible trace contaminant control (TCC) components and devices. This will be followed by shakedown and life endurance testing at MSFC. This paper provides details on the test setup, test matrix, durability evaluation of the β-HTCO reactor, and future test plan for γ-LW HTCO reactor at MSFC.