The development of new, robust, lightweight systems for CO2 removal during EVA is a crucial need for NASA. Current activity is focused on extending mission times without increasing the size and weight of the portable life support system (PLSS). Although CO2 sorbents that can be regenerated during EVA are being studied, these system add "on back" hardware, increasing weight and complexity, and reducing reliability. A simpler approach is to use a membrane system to separate CO2 and H2O from the O2 environment, however separating CO2 from O2 is difficult with standard membranes. However, developing a low pressure liquid sorbent that reversibly absorbs CO2, could facilitate the needed separation. In the Phase I project, Reaction Systems synthesized new CO2 low vapor pressure sorbents that had good reversible CO2 absorption capacity and demonstrated high selectivity for CO2 over O2 in a supported liquid membrane tests. Therefore we demonstrated the feasibility of employing a supported liquid membrane to control CO2 in EVA. In Phase II we will improve the performance by increasing the sorbent loading, reducing its viscosity, and optimizing the membrane support. We will then design and construct a prototype, that is sized to control the metabolic CO2 generation of a single crew member.More »
The most immediate application of the technology being proposed herein is the control of CO2 levels in the space suits of astronauts during EVA. This is a critical need as NASA mission objectives include extending the duration of EVA missions and the use of membrane technology has many important advantages over the regenerable sorbents and systems that are being developed currently. In addition, with only slight modification, the technology could be applied to CO2 control in spacecraft and on the surface of Mars.
In addition to the wide spread use for NASA applications, identifying effective means to reduce CO2 emissions from fossil fuel combustion is an area that is receiving much attention. The wide spread use of fossil fuels has caused a substantial rise in the concentration of atmospheric CO2, a recognized green house gas and further increases in atmospheric CO2 are not desirable. Thus, there currently is a great deal of interest in the development of methods to sequester CO2 from combustion processes. Other commercial applications would include the control of CO2 in underwater vehicles and other enclosed spaces and the development of rebreathers for SCUBA gear.
|Organizations Performing Work
|Reaction Systems, LLC
|Johnson Space Center (JSC)