Liquid densities of n-octane, ethylcyclohexane and their binary mixtures {(x) n-octane) + (1 − x) ethylcyclohexane} at temperatures from (283 to 363) K and pressures up to 60 MPa

•Liquid densities of n-octane, ethylcyclohexane and their binary mixtures were measured.•The results were correlated with modified Tait equation for each composition.•The isothermal compressibility and isobaric expansivity have also been derived from modified Tait equation.