A mixture containing 65.0 mole% acetone (Ac) and the balance acetic acid (AA) is separated in a continuous distillation column at 1 atm. A flowchart for the operation is as follows: The overhead stream from the column is a vapor that passes though a condenser. The condensed liquid is divided into two equal streams: one is taken off as the overhead product (distillate) and the other (the re-flux) is returned to the column. The bottom stream from the column is a liquid that is partially vaporized in a re-boiler. The liquid stream emerging from the re-boiler is taken off as the bottoms product, and the vapor is returned to the column as boil up. Negligible heat is lost from the column, so that the only places in the system where external heat transfer takes place are the condenser and the re-boiler.

(a) Taking 100 mol of feed as a basis, calculate the net heat requirement (cal) for the process. (You may neglect heats of mixing, although doing so for dissimilar liquids like acetone and acetic acid may introduce some error.)

(b) For the same basis, calculate the required heat input to the re-boiler and the required heat removal from the condenser.

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Feed 1 65% acetone, 35% acetic acid Feed 1 Overhead 2 Distillate 3 Reflux 4 Bottoms 5 Boilup 6 T(°C) 56.8 63.0 67.5 98.7 -Reflux 3 CONDENSER REBOILER Ĥ₁ Acetone 0 205 354 1385 Stream Data Liquid, 67.5°C, 65 mole % Ac, 35% AA Vapor, 63.0°C, 98 mole % Ac, 2% AA Liquid, 56.8°C, 98 mole % Ac, 2% AA Boilup Liquid, 98.7°C, 15.5 mole % Ac, 84.5% AA Vapor, 98.7°C, 54.4 mole % Ac, 45.6% AA Thermodynamic Data Ĥ (cal/mol) Overhead product 98% acetone. 2% acetic acid Bottoms product 15.5% acetone, 84.5% acetic acid 7205 7322 7403 7946 Acetic Acid Ĥ₁ Ĥ₂ 0 194 335 1312 5723 6807 6884 7420