Molecular Sieve CO₂ Removal Systems for Future Missions: Test Results and Alternative Designs

Carbon dioxide capture with zeotype materials

“…[219][220][221] A four bed molecular sieve system (4BMS) was installed in the System Integration Research Facility at NASA's Johnson Space Center (SIRF/NJSC) in 1992. 222 The 4BMS system consists of desiccant beds for water removal as well as zeolite adsorbent beds for CO 2 capture. The U.S. Skylab Program demonstrated over 10 000 h successful performance of zeolite molecular sieves (unknown structure information) in regenerative CO 2 removal from cabin atmosphere with CO 2 concentration of 0.39% (4 crew members) and 1% (8 crew members).…”

“…The U.S. Skylab Program demonstrated over 10 000 h successful performance of zeolite molecular sieves (unknown structure information) in regenerative CO 2 removal from cabin atmosphere with CO 2 concentration of 0.39% (4 crew members) and 1% (8 crew members). 222 Zeolite 5A was tested and applied in the ISS air revitalization system built by Honeywell, named Carbon Dioxide Removal Assembly (CDRA). 37,214,223 For practical applications, a system with compacted size is required due to the limited space in the ISS as well as other enclosed spaces.…”

“…213,214 Over-crowded living spaces and poorly ventilated areas as well as cabins in the ISS have high CO 2 concentrations over 3000 ppm. 215–217 It has been suggested that high concentration CO 2 of 3500–5000 ppm (0.3–0.5% CO 2 ) is harmful for human health. 218 Therefore, the removal of excessive CO 2 from these spaces has been explored using various materials, including zeolites.…”