Electrochemically Induced CO 2 Capture Enabled by Aqueous Quinone Flow Chemistry

作者：Yan Jing, Kiana Amini, Dawei Xi, Shijian Jin, Abdulrahman M. Alfaraidi, Emily F. Kerr, Roy G. Gordon, Michael J. Aziz · 发表于：ACS Energy Letters · 年份：2024 · DOI：10.1021/acsenergylett.4c01235 · 被引用次数：49 · 研究领域：Advanced battery technologies research、CO2 Reduction Techniques and Catalysts、Ionic liquids properties and applications

Electrochemically driven CO 2 capture processes utilizing redox-active organics in aqueous flow chemistry show promise for nonflammability, continuous-flow engineering and the possibility of being driven at a high current density by inexpensive, clean electricity. We show that deprotonated hydroquinone–CO 2 adducts, whose insolubility limits the utility of the quinone–hydroquinone redox couple, become soluble when alkylammonium cations are introduced. Consequently, we introduced alkylammonium groups to anthraquinone via covalent bonds, making the resulting bis[3-(trimethylammonio)propyl]anthraquinones (BTMAPAQs) soluble. We report the first aqueous quinone flow chemistry-enabled electrochemical CO 2 capture/release process, which occurs at ambient temperature and pressure, and show that it proceeds via both pH-swing and nucleophilicity-swing mechanisms. 1,5-BTMAPAQ reaches the theoretical capture capacity of two CO 2 molecules per quinone from 1-bar CO 2 –N 2 mixtures, for which the CO 2 partial pressure is as low as 0.05 bar, or the applied current density is as high as 100 mA/cm 2, or the organic concentration is as high as 0.4 M. The energetic cost ranges from 48 to 140 kJ/mol CO 2 . In a crude simulated flue gas composed of 3% O 2, 10% CO 2, and 87% N 2, 1,5-BTMAPAQ electrolyte reversibly captured and released 50% of the theoretical capacity during an exposure of over 4 h. It outperforms its isomeric counterparts 1,4-, and 1,8-BTMAPAQ in capture capacity and O 2 tolerance...