Hydrogen bond-stabilized mixtures for efficient carbon dioxide capture

In this study, we investigate the use of hydrogen bond-stabilized amine-based mixtures (a class of systems hereafter referred to as Hydrogen Bond-Stabilized Mixtures, HBSMs; e.g., n-butylamine with glycerol or guanidinium chloride) as an alternative approach to improve carbon dioxide capture efficiency while avoiding massive solvent evaporation. CO 2 capture experiments reveal that these mixtures exhibit improved sorption capacity compared to pure amines, while the presence of hydrogen bond acceptors plays a crucial role in stabilizing the systems, due to the establishment of an extended hydrogen-bond network. ATR-IR analyses confirm that CO 2 capture occurs through a combination of physical and chemical absorption; on the other hand, TGA data reveal a substantial reduction in solvent evaporation rates, particularly in the n-butylamine/glycerol mixture, where evaporation decreased by more than an order of magnitude compared to pure amine. The high CO 2 absorption capacity and reduced amine volatility of these mixtures open a promising avenue for more sustainable and energy-efficient carbon capture technologies, paving the way for relevant industrial applications. • New Hydrogen-Bond Stabilized Mixtures (HBSM) are formulated. • HBSM are proposed as green and low cost CO 2 sorbents. • Very promising CO 2 uptake values are obtained with amine-based HBSMs. • The establishment of an extended hydrogen bond network dramatically stabilizes the mixture, without impacting the uptake capacity.