In this work, surface tensions, densities, viscosities, and refractive indices of biodiesel +1-hexanol, 4-methyl-2-pentanol, and 2-ethyl-1-butanol have been measured from 288.15 to 338.15 K at 0.1 MPa throughout the whole composition range. Du Noüy ring tensiometer, vibrating tube densimeter, glass capillary viscosimeter, and Abbemat refractometer are used to measure the surface tensions, densities, viscosities, and refractive indices, respectively. Our experimental results for the pure alcohols agree with literature values within average absolute percentage deviations of 1.171, 0.024, 0.737, and 0.061 % for the surface tension, density, viscosity, and refractive index, respectively. Experimental densities and viscosities of some of our biodiesel mixtures satisfy the limits set by the diesel fuel standard (EN 590), becoming potential substitutes of conventional diesel. Kinematic viscosities show a minimum value at alcohol mass fractions between 0.4 and 0.9. Thermodynamic properties and derived properties have been correlated using different equations reported in the literature.

This work presents experimentally determined densities and viscosities of biodiesel blended with 1-pentanol, 2-pentanol, and 2-methyl-1-butanol between 288.15 and 338.15 K at 0.1 MPa. The densities are measured using a vibrating tube densimeter, and the kinematic viscosities, using a glass capillary viscometer. The measured density and viscosity of the pure components agree with values reported in the literature within average absolute percentage deviations of 0.04 and 0.83%, respectively. The excess molar volumes and viscosity deviations show positive and negative deviations from ideality, respectively. The Redlich−Kister equation is used to represent the composition behavior of the excess molar volumes and viscosity deviations. The experimental kinematic viscosities have a minimum value over a composition range of 50−90% alcohol by weight. The McAllister equation correlates the kinematic viscosity within an average absolute percentage deviation of 1.77%, while the Nava-Ri ́os equation correlates the kinematic viscosity within 0.88%.