Issue 80, 2023

Formation of choline salts and dipolar ions for CO2 reactive eutectic solvents

Abstract

Choline-based sorbents derived from imidazole (ImH), phenol (PhOH), pyrrole-2-carbonitrile (CNpyrH), and 1,2,4-triazole (TrzH) are developed for CO2 capture to enable alternative regeneration approaches over aqueous amines. During synthesis, the equilibrium between [Ch]+[OH] and Ch± dipolar in water shifts to support the formation of Ch±ImH and Ch±PhOH in the presence of ImH and PhOH upon drying. In contrast, salts of [Ch]+[CNpyr] and [Ch]+[Trz] were obtained with CNpyrH and TrzH, as confirmed by NMR and FTIR spectroscopy. Density functional theory (DFT) calculations support a spontaneous proton transfer from CNpyrH and TrzH to Ch±, while they show an energy barrier in the case of ImH. These sorbents formed eutectic solvents upon mixing with ethylene glycol (EG) where deprotonation of EG and subsequent binding of CO2 contributed to capacities up to 3.56 mol CO2 kg−1 at 25 °C and 1 bar of CO2. The regenerability of the eutectic solvents was demonstrated by dielectric heating via microwaves (MWs) in support of renewable energy utilization. This study shows the impact of proton sharing on the CO2 capacity and regenerability of eutectic sorbents as molecular design guidance.

Graphical abstract: Formation of choline salts and dipolar ions for CO2 reactive eutectic solvents

Supplementary files

Article information

Article type
Communication
Submitted
11 Jul 2023
Accepted
12 Sep 2023
First published
12 Sep 2023

Chem. Commun., 2023,59, 12027-12030

Author version available

Formation of choline salts and dipolar ions for CO2 reactive eutectic solvents

R. Dikki, E. Cagli, D. Penley, M. Karayilan and B. Gurkan, Chem. Commun., 2023, 59, 12027 DOI: 10.1039/D3CC03272H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements