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Single-Stage Batch Distillation: Example Problems

Try to solve these problems before watching the solutions in the screencasts.

Example Problem 1

50 moles of an ethanol-water mixture are loaded into a pot still and heated. When the first distillate is collected, the head temperature (vapor temperature) is 84°C. The still is run until the head temperature is 89°C. What is the total amount of distillate collected? What are the compositions of the distillate and the waste products?

An example problem on single stage batch distillation.
Example Problem 2

A single-stage batch still operating at 760 mm Hg pressure is charged with 75 mol of a 82 mol% methanol(1)/18 mol% water(2) mixture. Assume the mixture is an ideal solution.
How much distillate will be collected if the average distillate concentration desired is 90.0%?
How many moles will remain in the still and what is its methanol concentration?
The Antione equations (where T is in Celsius) are: 

Methanol:   log10P1sat=8.081(1582T+239.7)

Water:   log10P2sat=8.071(1731T+233.4)