A charge of 100 lbmol of a hydrocarbon mixture containing 10 mol% propane, 30 mol% n-butane, 10 mol% n-pentane, and the balance n-hexane is to be separated in a batch rectifier equipped with a partial reboiler, a total condenser with a liquid holdup of 1.0 ft3, and a column with the equivalent of eight theoretical stages and a total holdup of 0.80 ft3. The pressure in the condenser is 50.0 psia and the column pressure drop is 2.0 psi. The rectification campaign or operating policy, given as follows, is designed to produce cuts of 98 mol% propane, 99.8 mol% n-butane, and a residual cut of 99 mol% n-hexane, and two intermediate cuts, one of which may be a relatively rich cut of n-pentane. All five operating steps are conducted at a molar vapor boilup rate of 40 lbmol/h. Use a suitable batch-distillation computer program to determine the amounts and compositions of all cuts.Make suggestions as to how you might alter the operation steps so as to obtain larger amounts of the product cuts and smaller amounts of the intermediatecuts.

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Reflux Stop Criterion Step Ratio 5 98% propane in accumulator 1 2 20 95% n-butane in instantaneous distillate 3 25 99.8% n-butane in accumulator 80% n-pentane in instantaneous distillate 99% n-hexane in the pot 4 15 25