Thermophysical Properties Derived from Density and Kinematic Viscosity Measurements of Blends of <i>Chrysophyllum albidum</i> Biodiesel and Pure Diesel Fuel

Binary blends of 5%, 10% and 20% biodiesel (Bd) derived from unconventional vegetable oil of <i>Chrysophyllum albidum</i> with pure diesel (Dp) were investigated in this study. The density of the binary blends was evaluated at pressures up to 40MPa and varying the temperature from 293.15K to 353.15K. Similarly, the kinematic viscosity of the samples was measured and presented in this work at atmospheric pressure in a temperature range from 293.15K to 373.15K. The density values were adjusted from the modified Tait-like equation with mean absolute deviations of about 0.005%. Density values were used to estimate the isothermal compressibility coefficient of the blends of biodiesel (Bd) with pure diesel (Dp). The density and kinematic viscosity of ethyl biodiesel are higher than those of the Bd/Dp blends and decrease with increasing temperature. The density and kinematic viscosity of the blends decrease with the proportion or amount of biodiesel in the Bd/Dp blends in the order B5 < B10 < B20. The isothermal compressibility of the samples increases with increasing temperature at constant pressure and decreases with increasing pressure along the isotherm. The absolute mean deviations between the measured densities and those calculated using the Tait-Like equation for our examined samples at around 0.005% confirm the accuracy of the modeling and the reliability of the calculated isothermal compressibility coefficient values.