An ordinary, single-feed distillation column is separating propane, nbutane, isobutane, 2-methyl-butane, and n-hexane. There are 37 trays in the column, and feed location in column is tray 18 below condenser (input as liquid), reflux ratio is 2.8 , pressure is 4.80 bar (operate column at constant pressure), total condenser with saturated liquid reflux, kettle type reboiler, feed flow rate is \(300.0 \mathrm{kmol} / \mathrm{h}\), feed mole fractions are propane \(=0.170, \mathrm{n}\)-butane \(=0.403\), isobutane \(=0.160,2\)-methyl-butane \(=0.134\), and \(n-\) hexane \(=0.133\). Feed pressure is 4.9 bar, feed is at \(32^{\circ} \mathrm{C}, \mathrm{D}=51.0 \mathrm{kmol} / \mathrm{h}\), 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. Record the following values: Condenser temperature = C C, reboiler temperature condenser cal/sec, Qreboiler cal/sec Distillate product mole fractions: Bottoms product 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 2-methyl-butane the LK and n-hexane the HK. What operating parameter did you change, and what is its new value? Condenser temperature C, reboiler temperature C Distillate product mole fractions: Bottoms product mole fractions: