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Title: Distributed direct air capture by carbon nanofiber air filters
The rising atmospheric CO2concentration is one of the biggest challenges human civilization faces. Direct air capture (DAC) that removes CO2from the atmosphere provides great potential in carbon neutralization. However, the massive land use and capital investment of centralized DAC plants and the energy-intensive process of adsorbent regeneration limit its wide employment. We develop a distributed carbon nanofiber (CNF)–based DAC air filter capable of adsorbing CO2downstream in ventilation systems. The DAC air filter not only has the potential to remove 596 MtCO2year−1globally but can also decrease energy consumption in existing building systems. The CNF-based adsorbent has a capacity of 4 mmol/g and can be regenerated via solar thermal or electrothermal methods with low carbon footprints. Through life cycle assessment, the CNF air filter shows a carbon removal efficiency of 92.1% from cradle to grave. Additionally, techno-economic analysis estimates a cost of $209 to 668 in capturing and storing 1 tonne of CO2from direct air.  more » « less
Award ID(s):
2114117
PAR ID:
10649700
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science
Date Published:
Journal Name:
Science Advances
Volume:
11
Issue:
42
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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