Chapter 11.12, Problem 27P

In a process you need to evaluate the flash separation of an equimolar mixture of 1,3-dioxolane (1) + n-heptane (2) at 70°C. However, you can only find experimental data at 40°C. From your thermodynamics class, you remember that the Wilson equation can be used to predict behavior at one temperature if you parameterize your system at another temperature. This seems to be the perfect opportunity to use the Wilson equation.

1. A. Using the data in Table P11-27, parameterize the system using the Wilson equation at 40°C.
2. B. Determine the parameters for this system at70°C.
3. C. Run a flash calculation at 70°C and 675 mm Hg on an equimolar feed of 100 mol/min. Determine the amount and composition of the stream(s) leaving the flash distillation unit.
4. D. After completing parts (A, B, and C), you find experimental data for this system at 70°C. You notice the following: P^bubble (x₁ = 0.5) = 665 mm Hg; P^dew (y₁ = 0.5) = 517 mm Hg. Discuss the results from part (C) in light of this information.