Compressed Liquid Densities for Binary Mixtures at Temperatures from 280-440K at Pressures up to 200 MPa

A method for predicting liquid densities of binary mixtures from heat of vaporization and liquid density at boiling point temperature (?Hvap and n b ? ) as scaling constants, is presented. B2(T) follows a promising corresponding-states principle. Calculation of ?(T) and b(T), the two other temperature-dependent constants of the equation of state, are made possible by scaling. As a result ?Hvap and n b ? are sufficient for determination of thermophysical properties of liquid mixtures. We applied the procedure to predict liquid densities of (x1 n-butane + x2 isobutane) at compressed state with temperature range from 280 to 440 K and pressures up to 200 MPa. The experimental liquid densities were correlated satisfactory with our procedure and the results are within 5%.