Protic amino-2-propanol hydrochloride-based deep eutectic solvents with multiple hydrogen bond sites for efficient capture of NH3

Abstract

The ammonia (NH3) emitting into the atmosphere during the industrial process of synthesizing ammonia not only constitutes serious air pollution, but also causes a waste of ammonia resources. Therefore, there is an urgent need to develop efficient ammonia capture technology. In this work, we report an efficient capture of NH3 by protic amino-2-propanol hydrochloride-based deep eutectic solvents (DESs). These DESs with multiple hydrogen bond sites exhibit remarkable NH3 uptake with up to 0.244 g NH3 per g DES at 293 K and 1 bar and good recyclability. Further mechanism study suggested that the introduction of hydrogen bond donors with rich hydroxyl groups provides a large number of hydrogen bond sites to achieve efficient absorption of NH3 through the intermolecular hydrogen bonds interaction. This research has obtained an alternative absorber for the capture of NH3, and it also provides ideas for the design of high-efficiency NH3 deep eutectic solvents absorbent.