Density, Viscosity, and Refractive Index of Ternary Mixtures of d-Glucose in the Presence of Aqueous 2-Hydroxyethylammonium Acetate Protic Ionic Liquids at Different Temperature Range from 288.15 to 318.15 K

The density, viscosity, and refractive index of ternary mixtures comprising d-glucose, water, and the protic ionic liquids (2-hydroxyethyl)ammonium acetate [2-HEA]Ac, bis(2-hydroxyethyl)ammonium acetate [BHEA]Ac, and tris(2-hydroxyethyl)ammonium acetate [THEA]Ac were determined across a temperature range of 298.15 to 318.15 K. The data have been used to calculate the apparent molar volume (V_φ) and standard partial molar expansibility (E_φ⁰). The standard partial molar volume (V_φ⁰) measured over the studied temperature range indicates that the solute–solvent interaction between [2-HEA]Ac and d-glucose in the presence of water is 125.419 cm³ mol^–1. Notably, this interaction is stronger than those observed with the other two protic ionic liquids examined in the study. Additionally, the viscosity B-coefficient was determined by utilizing the Jones–Dole equation, providing further insights into solute–solvent interactions and viscosity properties. Also, the molar refraction (R_M) was calculated by using the Lorentz–Lorenz equation. For further investigating the interactions governing the studied systems, the conductor-like screening model (COSMO) analysis was employed, revealing that the more negative dielectric energy of [2-HEA]Ac compared to the other PILs indicated stronger interactions between [2-HEA]Ac and d-glucose. These findings suggest that [2-HEA]Ac has a stronger interaction with d-glucose than other protic ionic liquids.