Supported Ionic Liquid Membranes for Carbon Dioxide Management in Spacecraft Cabin Atmospheres

Long-duration human space exploration demands robust technologies for gas separations, and in particular carbon dioxide carbon dioxide ([Formula: see text]) capture for Environmental Control and Life Support Systems (ECLSS). Historically accomplished via pressure- and temperature-swing adsorption in solid sorbent beds, spacecraft [Formula: see text] capture is a mission-critical capability to maintain a livable atmosphere inside a human habitat. Supported ionic liquid membranes (SILMs) present an attractive method for stable, isothermal, and isobaric [Formula: see text] control that negates the need for liquid pumps and multiple gas/liquid contactor units. SILMs allow for continuous inline separation using two gas flows; the feed gas mixture flows over one side of the membrane, where the supported liquid sorbent captures and transports the target gas to the other side of the membrane and releases it into another gas stream. This paper presents the [Formula: see text] separation and mass transfer behavior of novel SILMs using the ionic liquid 1-butyl-3-methylimidazolium acetate and compares their performance to other liquid sorbent-based [Formula: see text] separation systems for ECLSS.