(520g) Post Spinning Modification of Porous Organic Cage Fiber Sorbents for CO2 Capture
AIChE Annual Meeting
Wednesday, November 16, 2022 - 2:00pm to 2:18pm
It is clear that CO2 capture from point sources and direct capture from ambient air is necessary to achieve global climate goals and avoid excessive global temperature increases. One method to develop effective adsorbents for CO2 is to impregnate mesoporous or microporous materials with polyamines like branched polyethylenimine (PEI) or tetraethylenepentamine (TEPA). Here a new class microporous materials, porous organic cage (POCs) are explored as a base material for PEI impregnation. CC3 is the POC used in this work and it has been previously spun into polymeric fiber sorbents for adsorptive separation applications. CC3 is composed of chemically weak imine bonds which should be vulnerable to degradation from primary amines present in PEI. Unexpectedly, CC3 maintains its microporosity and chemical structure after extended PEI exposure. The CC3-PEI fibers are characterized via TGA, SEM, FTIR, N2 physisorption at 77K, and CO2 isotherms. CC3 fibers impregnated with PEI consistently showed higher CO2 uptakes at low pressures showing that PEI was contributing to CO2 capture along with CC3. Breakthrough studies were conducted with these CC3-PEI fibers and compared to mesoporous silica-PEI fibers to compare the kinetics of CO2 uptake. This work shows that imine based POCs can be combined with PEI to make them effective adsorbents for CO2 capture.