Solve the following binary distillation problem for a stripping column using a modified version of the spreadsheet in Figure \(5 . A 1.150 .0 \mathrm{kmol} / \mathrm{h}\) of a 25.0 \(\mathrm{mol} \%\) n-butane and \(75.0 \mathrm{~mol} \% \mathrm{n}\)-hexane mixture is fed to a stripping column as a saturated liquid at 4.0 bar. The column is at 4.0 bar, has a partial reboiler, the boilup ratio \(\approx / \mathrm{B}=1.0\), and \(\mathrm{CMO}\) is assumed to be valid. Bottoms product is \(99.8 \mathrm{~mol} \% \mathrm{n}\)-hexane. Find bottoms flow rate \(\mathrm{B}\), distillate flow rate \(\mathrm{D}\), mole fractions of distillate and bottoms, and the number of equilibrium stages needed. Report vapor and liquid mole fractions leaving each stage and the temperature of each stage.

Figure 5-A1

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A 1 Figure 5-A1. B D E F Starting at stripping column top, calculate dew point & bot op. eq. of top stage 2 Input equilibrium constants, Eq. (2-28), then hand transfer y values & calculate next stage. G 3 K const 4 nButane 5 nPentane 6 nHex aT1 aT2 -1280557 -1524891 -1778901 aT6 ap1 ap2 ap3 0 7.94986 -0.96455 0 0 0 7.33129 -0.89143 0 0 0 6.96783 -0.84634 0 0 8 Feed rate 7 Input parameters and CMO Preliminary Calculations 9 Input T, p, feed mol frac |10 T_R=F10+459.7 11 Lbar F = B8 100.0 Vbar/B pick p,kPa 9 Vbar =D8*D11 90 300 Pick T deg C 67.435 613.08 psia 14.69*D9/101.3 100.0 B = B11/(D8+1) 43.504 T F =1.8*F9+32 153.38 10.0 D =Vbar =F8 90.0 12 XC6 bot spec 0.962 assume c4 bot 0 C5bot-1-B12-D 0.038 13 ZC4 0.350 ZC5 0.450 zc6 0.200 14 Table 5A2: yc4 dist 0.38889 yC5 dist 0.49578 YC6 dist 0.11533 15 16 Working register y values. Stage 1 use ydist values & other stages use yop values from previous stage 17 frac nButane 0.38889 frac npent 18 Report values in Table 5-A1. 0.49578 frac n hex 0.11533 19 Dew Point Calc: 20 xnb Stage j 0.15751 KnB Strip op. eqs. Stage j+1 2.4691 yopC4 0.17501 21 xnPen |22 xnHex 0.54188 KnPen 0.91493 yopC5 0.59786 0.30062 KnHex 0.38364 yop C6 0.22713 23 SUM(B20:B22) 24 1000*(B23-1) -8.81E-04 25 Factor 1000 is for less error. 26 Data tab menu bar, What if analysis, 27 Goal seek B24 = 0 by changing F9 1.0000 sum yop, F20+F21+F22 1.00000 Lbar/Vbar =B11/F11 1.1111 C4 intercept =-(F24-1)*D12 C5 intercept =-(F24-1)*F12 C6 intercept =-(F24-1)*B12 0 -0.004222 -0.10689