Abstract
A polymeric ionic liquid (PIL), with quaternary ammonium ions attached to the polymer matrix, displays CO2 affinity controlled by moisture. This finding led to the development of moisture swing absorption (MSA) for direct air capture of CO2. This work aims to elucidate the role of water in MSA. For some humidity range, CO2 absorption is an endothermic process associated with concurrent dehydration of the sorbent. The thermodynamic behavior of water indicates a decreased hydrophilicity of the PIL as the mobile anion transforms from CO3 2- to HCO3 - during CO2 absorption. The decrease in hydrophilicity drives water out of the PIL, carrying heat away. The mechanism is elucidated by molecular modeling based on density functional theory. The finding of spontaneous cooling during absorption and its mechanism in the PIL opens new possibilities for designing an air capture sorbent with a strong CO2 affinity but low absorption heat.
| Language | English (US) |
|---|---|
| Pages | 3986-3990 |
| Number of pages | 5 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 8 |
| Issue number | 17 |
| DOIs | |
| State | Published - Sep 7 2017 |
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ASJC Scopus subject areas
- Materials Science(all)
Cite this
Spontaneous Cooling Absorption of CO2 by a Polymeric Ionic Liquid for Direct Air Capture. / Wang, Tao; Hou, Chenglong; Ge, Kun; Lackner, Klaus S.; Shi, Xiaoyang; Liu, Jun; Fang, Mengxiang; Luo, Zhongyang.
In: Journal of Physical Chemistry Letters, Vol. 8, No. 17, 07.09.2017, p. 3986-3990.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Spontaneous Cooling Absorption of CO2 by a Polymeric Ionic Liquid for Direct Air Capture
AU - Wang,Tao
AU - Hou,Chenglong
AU - Ge,Kun
AU - Lackner,Klaus S.
AU - Shi,Xiaoyang
AU - Liu,Jun
AU - Fang,Mengxiang
AU - Luo,Zhongyang
PY - 2017/9/7
Y1 - 2017/9/7
N2 - A polymeric ionic liquid (PIL), with quaternary ammonium ions attached to the polymer matrix, displays CO2 affinity controlled by moisture. This finding led to the development of moisture swing absorption (MSA) for direct air capture of CO2. This work aims to elucidate the role of water in MSA. For some humidity range, CO2 absorption is an endothermic process associated with concurrent dehydration of the sorbent. The thermodynamic behavior of water indicates a decreased hydrophilicity of the PIL as the mobile anion transforms from CO3 2- to HCO3 - during CO2 absorption. The decrease in hydrophilicity drives water out of the PIL, carrying heat away. The mechanism is elucidated by molecular modeling based on density functional theory. The finding of spontaneous cooling during absorption and its mechanism in the PIL opens new possibilities for designing an air capture sorbent with a strong CO2 affinity but low absorption heat.
AB - A polymeric ionic liquid (PIL), with quaternary ammonium ions attached to the polymer matrix, displays CO2 affinity controlled by moisture. This finding led to the development of moisture swing absorption (MSA) for direct air capture of CO2. This work aims to elucidate the role of water in MSA. For some humidity range, CO2 absorption is an endothermic process associated with concurrent dehydration of the sorbent. The thermodynamic behavior of water indicates a decreased hydrophilicity of the PIL as the mobile anion transforms from CO3 2- to HCO3 - during CO2 absorption. The decrease in hydrophilicity drives water out of the PIL, carrying heat away. The mechanism is elucidated by molecular modeling based on density functional theory. The finding of spontaneous cooling during absorption and its mechanism in the PIL opens new possibilities for designing an air capture sorbent with a strong CO2 affinity but low absorption heat.
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UR - http://www.scopus.com/inward/citedby.url?scp=85029126217&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.7b01726
DO - 10.1021/acs.jpclett.7b01726
M3 - Article
VL - 8
SP - 3986
EP - 3990
JO - Journal of Physical Chemistry Letters
T2 - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 17
ER -