The compressibility factor of nonassociated chain molecules composed of hard convex core Yukawa segments was derived with SAFT-VR and an extension of the Barker-Henderson perturbation theory for convex bodies. The temperature-dependent chain and dispersion compressibility factors were derived using the Yukawa potential. The effects of temperature, packing fraction, and segment number on the com...

The vapor-liquid equilibrium of binary mixtures of xenon + SF6 has been measured at nine temperatures from 235.34 to 295.79 K and pressures up to 6.5 MPa. The mixture critical line is found to be continuous between the critical points of the pure components, and hence, the system can be classified as type I phase behavior in the scheme of van Konynenburg and Scott. The excess Gibbs free energie...

The SAFT-VR equation of state is combined with a semi-continuous thermodynamic approach to model several synthetic and crude oil systems. In our approach, the oil fractions are defined by a continuous distribution that is then represented as discrete pseudo-components using the Gaussian quadrature method. The SAFT-VR parameters for the pseudo-components are obtained from simple linear relations...

The molecular-based SAFT equation of state has proven to be very versatile in the prediction of fluid phase equilibria. However, in common with all analytic equations of state, SAFT exhibits classical behavior in the critical region rather than the nonanalytical, singular behavior seen in real fluids. As a result, accurate agreement over the whole phase diagram cannot be obtained and must be lo...

Molecular dynamics (MD) simulations of direct and derivative thermodynamic properties of the Mie n-6 fluid (n=8, 10, and 12) have been performed for liquid to supercritical states. Using the results, an in depth test of the monomer-monomer interaction estimation of a recently derived statistical associating fluid theory of variable range (SAFT-VR) equation of state [Lafitte et al., J. Chem. Phy...

An accurate prediction of phase behavior at conditions far and close to criticality cannot be accomplished by mean-field based theories that do not incorporate long-range density fluctuations. A treatment based on renormalization-group (RG) theory as developed by White and co-workers has proven to be very successful in improving the predictions of the critical region with different equations of...

A new CO2/CH4 gas separation process is presented in this paper. Capture of CO2 from natural gas is carried out using an n-alkane solvent in a conventional physical absorption process. A methodology to find optimal process condition and solvent has been developed using an advanced equation of state (SAFT-VR), process modelling-optimisation software (gPROMS), and detailed process cost estimation...

The phase equilibria of non-conformal square-well monomer–dimer systems are examined using Gibbs ensemble Monte Carlo simulation and compared with results from the statistical associating fluid theory for potentials of variable attractive Ž . range SAFT-VR . For the first system of interest the square-well segments are of equal diameter and well-depth, the monomer has an attractive range of l s...

In a recent paper we predicted the fluid-phase equilibria of n-butane + n-alkane binary mixtures using the statistical associating fluid theory for chain molecules with attractive potentials of variable range (SAFTVR). Now we focus on the methane + n-hexane system, again using the SAFT-VR approach. The methane + n-hexane system exhibits type V phase behavior, in which partial miscibility of the...