Measurement and correlation of biodiesel densities at pressures up to 130 MPa

Densities of pure methyl linoleate, usually a significant biodiesel component, as well as densities of a mixture of fatty acid methyl esters (purified biodiesel) were measured at pressures between 0.4 and 130 MPa and temperatures between 278 K and 397 K. Measured data were used for fitting parameters of two correlation models and compared to calculated densities using the VTPR (Volume Translated Peng–Robinson) group contribution equation of state. The comparison indicates that VTPR shows precisions which are mostly adequate for process simulation purposes as well as for estimation of deduced thermophysical properties that are based upon density.