Viscosity and Excess Volume at High Pressures in Associative Binaries
Résumé
The dynamic viscosity η and the density ρ of three pure substances (water, 2-propanol, diacetone alcohol) and the three associated binaries were measured versus temperature T (303.15, 323.15, and 343.15 K) and pressure P. For the binary systems the mole fractions x of each component were, successively, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1. For viscosity the experimental results (P ≤ 100 MPa) represent a total of 540 data points: 54 for the pure substances and 486 for the binary mixtures (x ≠ 0 and x ≠ 1). For density the experimental results (P ≤ 70 MPa) represent 1260 values: 126 for the pure substances and 1134 for the binary mixtures (x ≠ 0 and x ≠ 1). The mixtures with water are highly associative and the curves for the variation of η with composition exhibit a maxima. The variations of the excess activation energy of viscous flow ΔGE are discussed. Moreover, the measurements of ρ are sufficiently accurate to determine the excess volumes VE versus pressure, temperature, and composition.