Refractive Index of 48 Neat Deep Eutectic Solvents and of Selected Mixtures: Effect of Temperature, Hydrogen-Bonding Donors, Hydrogen-Bonding Acceptors, Mole Ratio, and Water

The refractive index (RI) is an important physiochemical property of deep eutectic solvents (DESs) for application in the optical identification specific substances or measuring concentration solutes solutions. However, available data on RI DESs limited. Here, a systematic investigation 48 typical and 30 mixtures with water was conducted under atmospheric pressure. effect temperature range 293.15–338.15 K, hydrogen-bonding donors (HBDs), acceptors (HBAs) investigated. Furthermore, as function mass percentage 20–80% also studied. It found that its aqueous binary decreases linearly increase temperature. HBDs HBAs had significant influence DESs. Among them, choline chloride (ChCl)/phenol ChCl/o-cresol were obviously higher than those other addition would decrease DESs, DES content (wt %) increases 20 10 there no linear relationship between content.