Measurement and correlation of density and viscosity of binary mixtures of fatty acid (methyl esters + methylcyclohexane)

Highlights: • Density and viscosity of three binary mixtures of fatty acid methyl esters and methylcyclohexane were investigated. • Excess molar volumes and viscosity deviation of the mixtures were fitted to Redlich-Kister equation. • The thermodynamic functions of activation for the flow process for mixtures were calculated. -- Abstract: The thermodynamics properties of the mixtures of biodiesel and petroleum-based fuel are useful for the research of blending fuels. Biodiesel is mainly consisting of fatty acid alkyl esters. Densities and viscosity for the binary mixtures of three fatty acid methyl esters (methyl decanoate, methyl dodecanoate and methyl tetradecanoate) with methylcyclohexane (MCH) were measured at 7 temperatures from 293.15 to 323.15 K and at atmospheric pressure. Excess molar volumes and viscosity deviations of the three binary systems have been correlated and fitted to Redlich-Kister equation. The change of enthalpy, entropy and Gibbs energy of activation for the flow process for the binary mixtures were calculated on the basis of Eyring's absolute reaction rate theory. The experimental data and correlated results could provide important information for the research of the blends of biodiesel and diesel oil.