In 1991, Hamilton Standard initiated an Independent Research and Development program to enhance the performance characteristics of solid amine based regenerative CO2 removal systems. A solid amine based system had been selected by NASA/JSC for Extended Duration Orbiter missions. As a result of this research effort, two promising new solid amine candidates, designated HSC+ and HSG, were identified. Bench scale testing indicated that these formulations provided 25% to 33% greater initial cyclic capacity when compared to the baseline HSC solid amine sorbent.
This paper reports on comparative life testing of HSC, HSC+ and HSG. The solid amine sorbents were exposed to accelerated life testing with laboratory air under controlled temperature and flow conditions. At various time intervals over a duration of approximately 12,700 hours, the solid amine candidates were packed into a subscale reactor which was designed for evaluating cyclic and equilibrium CO2 capacities under various operating conditions and subjected to a uniform series of performance tests.
Life exposure testing is continuing. To date, the HSG formulation, which provides 25% initial performance margin over HSC, was found to exhibit almost three times better life characteristics than HSC or HSC+, thus offering more stable operation and improved performance for extended missions.