Physical Properties of Renewable Solvents Cyrene, Dimethylisosorbide, γ-Valerolactone, Cyclopentylmethyl Ether, and 2-Methyltetrahydrofuran

Abstract

Renewable solvents derived from biomass have been regarded as promising alternatives to conventional organic solvents. A knowledge of the physical properties is crucial to accelerate the potential applications of a solvent, especially in industrial setups. Herein, we report water miscibility, surface tension (γ), density (ρ), dynamic viscosity (η), and refractive index (n^D) of five structurally different renewable solvents: cyrene, dimethylisosorbide (DMI), γ-valerolactone (GVL), cyclopentylmethyl ether (CPME), and 2-methyltetrahydrofuran (2-MeTHF). Density and dynamic viscosity are measured in the temperature range of 283.15–363.15 K and surface tension is measured in the range of 298.15–363.15 K. Water miscibility and refractive index are estimated under ambient conditions. Comparatively higher water miscibility of cyrene, DMI, and GVL hints toward the availability of a greater number of H-bonding sites. At 298.15 K, all physical properties frame similar trends, with cyrene being at the top followed by DMI and GVL with CPME and 2-MeTHF at the bottom. Entropy of surface formation (S^γ) and enthalpy of surface formation (H^γ) were estimated using temperature dependence of surface tension. Dynamic viscosity follows Arrhenius-like expression with the temperature. The role of structural organization and the strength of intermolecular forces of interactions in controlling physical properties of renewable solvents is established.