Implementing Paris Climate Accord is inhibited by the high energy consumption of the state-of-the-art CO2capture technologies due to the notoriously slow kinetics in CO2desorption step of CO2capture. To address the challenge, here we report that nanostructured TiO(OH)2as a catalyst is capable of drastically increasing the rates of CO2desorption from spent monoethanolamine (MEA) by over 4500%. This discovery makes CO2capture successful at much lower temperatures, which not only dramatically reduces energy consumption but also amine losses and prevents emission of carcinogenic amine-decomposition byproducts. The catalytic effect of TiO(OH)2is observed with Raman characterization. The stabilities of the catalyst and MEA are confirmed with 50 cyclic CO2sorption and sorption. A possible mechanism is proposed for the TiO(OH)2-catalyzed CO2capture. TiO(OH)2could be a key to the future success of Paris Climat e Accord.
Ionic liquids (ILs) have been used for carbon dioxide (CO2) capture, however, which have never been used as catalysts to accelerate CO2capture. The record is broken by a uniquely designed IL, [EMmim][NTf2]. The IL can universally catalyze both CO2sorption and desorption of all the chemisorption‐based technologies. As demonstrated in monoethanolamine (MEA) based CO2capture, even with the addition of only 2000 ppm IL catalyst, the rate of CO2desorption—the key to reducing the overall CO2capture energy consumption or breaking the bottleneck of the state‐of‐the‐art technologies and Paris Agreement implementation—can be increased by 791% at 85 °C, which makes use of low‐temperature waste heat and avoids secondary pollution during CO2capture feasible. Furthermore, the catalytic CO2capture mechanism is experimentally and theoretically revealed.
more » « less- NSF-PAR ID:
- 10392928
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 10
- Issue:
- 3
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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