Redlich-Kwong capabilities

Fuller, G. G., 1976. A modified Redlich-Kwong-Soave equation of state capable of repre.sent-ing the liquid state. Ind. Eng. Chem. Fund, 15 254—257. 

This work proposed the use of the Predictive Soave-Redlich-Kwong (PSRK) model to describe the phase equilibria in the flash distillation, using modified molecular parameters r and q for ethanol. In this way, the PSRK equation of state becomes more empirical, but keeps the predictive capabilities of the model. Furthermore, the introduction of new molecular parameters r and in the UNIFAC model gives more accurate predictions for the concentration of the congener in the gas phase for binary and ternary systems. 

What is needed then is a new equation comparable in computation speed to existing Redlich-Kwong correlations, but with the capability of correlating the properties of both polar and nonpolar mixtures. A new modified Van der Waals equation which meets these requirements is described in the next section of this report. 

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