Viscoelastic and acoustic properties of binary mixtures of ethanol and gasoline at 300 K

We have studied the viscoelastic and acoustic properties of binary mixtures of ethanol and gasoline at 300 K at various ethanol concentrations ranging from 10, 28, 46, 64, 82 and 100 percent. Ultrasonic velocity (𝑈), density (ρ) and viscosity (η) of these mixtures were measured by using ultrasonic interferometer, density bottle and Ostwald viscometer at the constant temperature 300 K. From these measured parameters, various viscoelastic and acoustic properties such as adiabatic compressibility (β), acoustic impedance (𝑍), intermolecular free length (𝐿_𝑓), relative association (𝑅_𝐴) and relaxation time (τ) were calculated. It is observed that some properties such as ultrasonic velocity, adiabatic compressibility, acoustic impedance and intermolecular free length exhibit a nonlinear variation with ethanol concentration indicating intermolecular interaction between ethanol and gasoline, while the other properties including density, relative association, viscosity and relaxation time increase steadily and linearly with ethanol concentration. We have attempted to interpret these results by using physicochemical properties of ethanol and gasoline, their intermolecular interaction, miscibility and compatibility. These results lead to a conclusion that ethanol is miscible and compatible with gasoline and it affects the properties of gasoline.