Question 1 [50 marks] A tray distillation column is used to separate a multicomponent mixture of propane, n-butane, n-pentane, and n-hexane. Vapor leaving the first tray (uppermost tray) is then fed

to a partial condenser which operates at 3.07 bara. The distillate composition is shown in Table 1 and the external reflux ratio is 2.5. Table 1. Distillate composition Component n-propane n-butane n-pentane n-hexane Composition (mol basis) 0.05 0.75 0.12 0.08 a. Sketch a schematic diagram for the process clearly showing the flow of vapor and liquid entering and leaving the column first tray (uppermost tray) and condenser. [5 marks] [10 marks] b. Calculate the distillate temperature (K). c. An air cooler is proposed to be used as the condenser. Can you please assess the suitability for this operation? [5 marks] d. Estimate the temperature of the column first tray (uppermost tray) (K). Assume that the pressure is 3.07 bara. [20 marks] e. Determine the vapor composition leaving the second tray (second uppermost tray) and state reasonable assumption(s) for your calculation. [10 marks]