An ordinary, single-feed distillation column is separating n-butane, npentane, benzene, and toluene. There are 17 trays in column, and feed location in column is tray 9 below condenser (input feed as liquid), reflux ratio is 1.6 , pressure is 3.0 bar (operate column at constant pressure), partial condenser with saturated liquid reflux, distillate product is a vapor, kettle type reboiler, feed flow rate is \(100 \mathrm{kmol} / \mathrm{h}\), feed mole fractions are n-butane 0.15 , n-pentane 0.43 , benzene 0.28 , and toluene 0.14 . Feed pressure is 3.1 bar, feed is at \(65^{\circ} \mathrm{C}\), distillate flow rate \(=58 \mathrm{kmol} / \mathrm{h}\), adiabatic column. Use the Peng-Robinson VLE package. Open a new blank file, simulate this system with RadFrac, and answer the following questions:

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1. Report the following values: Condenser temperature C, = C, reboiler temperature = Qcondenser = cal/sec, Qreboiler = cal/sec Distillate prod. mole fractions: Bottoms prod. mole fractions: 2. Was the specified feed stage the optimum feed stage? Yes No If no, the optimum feed stage is a. Closer to the condenser b. Closer to the reboiler 3. Which tray gives the largest column diameter with sieve trays when one uses the originally specified feed stage? Aspen tray # column diameter = meters. [Use the default values for number of passes (1), tray spacing (0.6096 m), minimum downcomer area (0.10), foaming factor (1), and overdesign factor (1). Set the fractional approach to flooding at 0.9. Use the Fair design method for flooding.] 4. Which components in the original problem are the LK and HK components? 5. Change one specification in the operating conditions (keep N, feed location (at original value), feed flow, feed composition, feed pressure, and feed temperature constant) to make benzene the LK and toluene the HK. What operating parameter did you change, and what is its new value? Condenser temperature C = C, reboiler temperature = Distillate product mole fractions: Bottoms product mole fractions: