Densities and bubble points of ternary mixtures of methane, n-butane and n-hexadecane and quaternary mixtures of methane, n-butane, n-heptane and n-hexadecane

• Published in: Fluid phase equilibria 2001-06, Vol.182 (1), p.111-119
• Main Authors: Fenghour, A, Trusler, J.P.M, Wakeham, W.A
• Format: Article
• Language: English
• Subjects: Binary mixtures; Bubble points; Chemical thermodynamics; Chemistry; Density; Exact sciences and technology; Experimental method; General and physical chemistry; Mixtures; Quaternary mixtures; Ternary mixtures; Thermodynamic properties
• ISSN: 0378-3812; 1879-0224
• DOI: 10.1016/S0378-3812(01)00385-5

The densities of three ternary mixtures of methane, n-butane and n-hexadecane and three quaternary mixtures of methane, n-butane, n-heptane and n-hexadecane were measured. The ternary mixtures were studied over the temperature range 295–350 K and the pressure range 8.3–49.3 MPa at the following methane mole fractions: 0.0185, 0.0358 and 0.0478 and corresponding n-butane mole fractions: 0.8680, 0.8527 and 0.8422. The quaternary mixtures were studied over the temperature range 317–460 K and the pressure range 26.9–49.7 MPa at the following methane mole fractions: 0.1210, 0.1717 and 0.2186 and corresponding n-butane mole fractions: 0.1632, 0.1537 and 0.1450 and n-heptane mole fractions: 0.5791, 0.5457 and 0.5148. The measurements were carried out in an automated isochoric instrument and their accuracy is estimated to be better than ±0.1%. The bubble points of the quaternary mixtures were determined from an analysis of the experimental isochores in the one- and two-phase regions. The new measurements have been used to assess the performance of the Peng–Robinson equation of state and the one-fluid corresponding states model. In single phase regions, the performance of the one-fluid model is found to be superior to that of the Peng–Robinson equation.