Infrared Analysis of Deep Eutectic Solvents (DESs) Containing Urea as a Hydrogen Bond Donor (HBD)

Due to the importance of environmentally friendly solvents, deep eutectic solvents (DES) have gained the attention of many. They have physical properties almost similar to ionic liquids, but DES is less toxic. In this study, several DESs have been produced using urea as a hydrogen bond donor (HBD). These DESs include choline chloride - urea, betaine - urea and magnesium chloride hexahydrate - urea. Infrared analysis results indicate the presence of hydrogen bonding between the hydrogen bond acceptor (HBA) and HBD, confirming the formation of DES. The absorption of these hydrogen bonds occurs in the range of 3600 - 2800 cm -1 , causing the absorption bands to broaden. The DESs produced can be used in various extraction and separation processes.