*Answers to problems with an asterisk are at the back of the book.
D1. A distillation column with a total condenser and a partial reboiler is fed a mixture of alcohols. The feed is 19 wt % methanol, 31 wt % ethanol, 27 wt % n-propanol, and 23 wt % n-butanol. (Methanol is most volatile and n-butanol is least volatile.) The feed rate is 12,000 kg/h. We desire a 97.8% recovery of ethanol in the distillate and a 99.4% recovery of n-propanol in the bottoms.
a. Estimate D and B and distillate and bottoms weight fractions.
b. List your assumptions, if any.
D2. What is the dew point of a vapor that is 30 mol% n-butane, 50 mol% n-pentane, and 20 mol% n-hexane at p = 760 mm Hg? Use Raoult’s law to predict K values. Find vapor pressures from ...