Carbon dioxide capture by new DBU‐based DES: The relationship between ionicity and absorptive capacity. Issue 7 (25th February 2021)

• Record Type: Journal Article
• Authors: Fu, Hui; Hou, Yunpeng; Sang, Haina; Mu, Tiancheng; Lin, Xufeng; Peng, Zhihua; Li, Peng; Liu, Jinhe
• Is Part Of: AIChE journal. Volume 67:Issue 7(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-02-25
• Subjects: absorption -- CO2 capture -- deep eutectic solvents -- desorption -- ionicity; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; 660.28
• DOI: 10.1002/aic.17244
• Languages: English
• ISSNs: 0001-1541

Abstract

Abstract: 1, 8‐Diazabicyclo[5.4.0]undec‐7‐ene (DBU)/imine, DBU/imide DESs were designed and synthesized as CO2 trapping agents. Toward this end, the optimal absorption temperature and the maximum absorption capacity were determined. It was found that ionicity is a key factor to affect the absorption capacity of CO2 . Combined with the ionicity calculation, a new CO2 capture mechanism has been proposed. HBD in DES can be divided into two parts. One can undergo proton transfer, obeying anion 2:1 absorption, whereas the other, without proton transfer, is amine 1:1 absorption. The degree of proton transfer in DES determines the ionicity and affects the absorption performance. The DFT calculation results confirmed this mechanism by micro perspective. DBU/2‐Pyrrolidinone and DBU/Oxazolidinone were proved to be good CO2 trapping agents with high absorption capacity, being 1.064 mol CO2 /mol DES and 0.827 mol CO2 /mol DES, respectively, and excellent recyclability when the mole ratio of HBA:HBD is 2:1. Abstract :