Novel amine-functional membrane for metabolic CO2 removal from spacesuit breathing loop

We developed a unique porous membrane material with amine-functional pore surfaces using surfactant templating techniques for CO2 removal from the breathing loop of spacesuits. We use evaporation during coating to induce the formation of surfactant micelles that self-organize into desirable pore structures. The membrane, with secondary amine functional groups inside the membrane pores, showed a dual-gas separation factor at 90degreesC that was ten times higher than the ideal Knudsen separation factor. A CO2 flux of 4 GPU (1GPU (gas permeation unit) = 10(-6) cm(3) (STP)/cm(2)-s-cmHg) was observed. When the temperature was reduced to 20degreesC, the mixed-gas separation factor increased two fold, indicating enhanced CO2 surface diffusion via active amine adsorption sites at lower temperatures. An amine-functional membrane could offer a unique alternative to NASA's current capability for regeneratively removing CO2 from spacesuit breathing loop.