Peneloux correction

It is notable that the Peneloux correction does not affect phase equilibrium. 

This study describes the accuracy of PC-SAFT for the prediction of phase equilibria and density for C02-N2-Ar-02 and C02-N2-Ar-02-S02 and provides a brief comparison with Peng-Robinson (PR) EoS [9] with the Peneloux correction. Furthermore, MD simulations were employed for the calculation of self- diffusion coefficients of CO2 in H2O and H2O in CO2. Recently proposed force-fields for H2O and CO2 were tested over a wide range of temperatures (283.15 K < J < 523.15 K) at a pressure of 20 MPa. 

Peneloux et al. [35] have introduced a clever method of improving the saturated liquid molar volume predictions of a cubic equation of state, by translating the calculated volumes without efffecting the prediction of phase equilibrium. The volume-translation parameter is chosen to give the correct saturated liquid volume at some temperature, usually at a reduced temperature Tr = T/Tc = 0.7, which is near the normal boiling point. It is possible to improve the liquid density predictions further by making the translation parameter temperature dependent. 

Peneloux, A. Rauzy, E. Freze, R. A consistent correction for Redlich-Kwong-Soave volumes. Fluid Phase Equilibr. 1982, 8, 7. 

An improvement can be achieved with the volume translation concept introduced by Peneloux et al [55]. The idea is that the specific volume calculated by the equation of state is corrected by addition of a constant parameter c. The volume translation has no effect on the vapor-liquid equilibrium calculation, as both the liquid and the vapor volume are simultaneously translated by a constant value. The procedure has also little effect on the calculated vapor volumes, as c is in the order of magnitude of a liquid volume far away from the critical temperature. 

Peneloux, A., E. Rauzy, and R, Freze A Consistent Correction for Redlich-Kwong-Soave Volumes, Fluid Phase Equilibria, vol, 8, p. 7,1982. 

Besides phase equilibria, volumetric properties play an important role in the design of near-critical reactors. This type of information is seldom available in the literature. Cubic equations of state with the volume correction proposed by Peneloux et al. can give predictions accurate enough for design purposes. 

In order to improve volume predictions (Peneloux et al., 1982) proposed a consistent correction for cubic EoS which does not change the vapour-liquid equilibrium conditions. Their method consists in translating the EoS by replacing v hy v+c and by b+c. The... 

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