Temperature-dependent thermophysical properties of 2-nitroanisole with butanol isomers: experimental study and Jouyban–Acree model correlation

Densities (ρ), viscosities (η) and speeds of sound (u) of binary mixtures of 2-nitroanisole (2-NA) with isomeric butanols – 2-methyl-2-propanol (t-BuOH), 2-butanol (s-BuOH) and 1-butanol (n-BuOH) – were measured over the entire composition range at 303.15, 308.15 and 313.15 K under 0.1 MPa. From these data, excess molar volumes (VE), viscosity deviations (Δη) and excess isentropic compressibilities (κsE) were derived to interpret molecular interactions. Predominantly negative VE and κsE values indicate strong hetero-associative interactions, especially hydrogen bonding between the nitro-group of 2-NA and hydroxyl protons of butanols. The interaction strength follows the order n-BuOH > s-BuOH > t-BuOH, attributed to steric and structural factors. The Jouyban–Acree model effectively correlated experimental data, yielding low mean relative deviations across temperatures. The findings provide valuable insights into molecular interactions and solvent design strategies for extraction processes involving nitroaromatic compounds.