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. CO2 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 CO2 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 CO2 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.