Volumetric properties of the binary mixture <Emphasis Type="Italic">n</Emphasis>-heptane+ethylbenzene mixtures at high temperatures and high pressures

New experimental data on the density of three (0.2393, 0.4856 and 0.7390 mole fraction of ethylbenzene) binary n-heptane+ethylbenzene mixtures have been measured with a constant-volume piezometer immersed in a precision liquid thermostat. These new experimental data covering a temperature range from 306 to 527 K and a pressure range of 0.1 to 11 MPa. The experimental data reported here have an uncertainty less than 0.06% for the density, 0.05% for the pressure, 15 mK for the temperature, and 0.012% for the concentration. Excess molar volumes were derived using measured values of density for the mixtures and for the pure components calculated with reference equation of state for n-heptane (Span and Wagner, 2003) and for the pure ethylbenzene (Frenkel et al., 2005). The derived values of excess molar volumes at atmospheric pressure were compared with the values reported by other authors in the literature. The effect of pressure on the excess molar volumes was studied.