Liquid Equilibrium Using the Equations of State Method

Vapor-Liquid Equilibrium Using the Equations of State Method 

Up to this point, we have used activity coefficients and models for to describe the nonideality in the liquid phase. In this section, we learn another approach to solve VLE problems, where we describe both the liquid and vapor phases using the fugacity coefficients. We term this approach the equation of state method. 

We again start by setting the fugacity coefficients for species i equal in each phase  

Next we apply Equation (7.19) to both the vapor and liquid phases  

Pure Species Equilibrium Using an Equation of State 

---