RTI uses cookies to offer you the best experience online. By clicking “accept” on this website, you opt in and you agree to the use of cookies. If you would like to know more about how RTI uses cookies and how to manage them please view our Privacy Policy here. You can “opt out” or change your mind by visiting: http://optout.aboutads.info/. Click “accept” to agree.
Trace CO2 capture by an ultramicroporous physisorbent with low water affinity
Mukherjee, S., Sikdar, N., O'Nolan, D., Franz, D. M., Gascon, V., Kumar, A., Kumar, N., Scott, H. S., Madden, D. G., Kruger, P. E., Space, B., & Zaworotko, M. J. (2019). Trace CO2 capture by an ultramicroporous physisorbent with low water affinity. Science advances, 5(11). https://doi.org/10.1126/sciadv.aax9171
CO2 accumulation in confined spaces represents an increasing environmental and health problem. Trace CO2 capture remains an unmet challenge because human health risks can occur at 1000 parts per million (ppm), a level that challenges current generations of chemisorbents (high energy footprint and slow kinetics) and physisorbents (poor selectivity for CO2, especially versus water vapor, and/or poor hydrolytic stability). Here, dynamic breakthrough gas experiments conducted upon the ultramicroporous material SIFSIX-18-Ni-beta reveal trace (1000 to 10,000 ppm) CO2 removal from humid air. We attribute the performance of SIFSIX-18-Ni-beta to two factors that are usually mutually exclusive: a new type of strong CO2 binding site and hydrophobicity similar to ZIF-8. SIFSIX-18-Ni-beta also offers fast sorption kinetics to enable selective capture of CO2 over both N-2 (S-CN) and H2O (S-CW), making it prototypal for a previously unknown class of physisorbents that exhibit effective trace CO2 capture under both dry and humid conditions.