The feed to Column C3 of the distillation sequence in Figure is given in Table 1.5. However, the separation is to be altered so as to produce a distillate that is 95 mol% pure isobutene with a recovery of isobutane in the distillate (SF) of 96%. Because of the relatively sharp separation in Column C3 between iC4 and nC4, assume all propane goes to the distillate and all C5s goes to the bottoms.(a) Compute the flow rates in Ibmolih of each component in each of the two products leaving Column C3.(b) What is the percent purity of the normal butane in the bottoms product?(c) If the purity of the isobutane in the distillate is fixed at 95%, what percent recovery of isobutane in the distillate will maximize the percent purity of normal butane in the bottoms product'?

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Column 2 Column 1 Column 3 iC, 3 Deethanized feed C1 C2 СЗ Component Ibmol/h C,Hs C3H3 iC,He nc,H10 iCH12 nCgH12 0.60 57.00 171.80 227.30 40.00 33.60 205.30 735.70 nCa -tich Ycinch Ibmol/h in Stream 5 2 4 Feed to C3 iC4 nCs-rich C;t-rich Feed to CI Feed to C2 C3 Component 0.00 0.000 0.00 0.60 0.60 С-Нь 0.00 0.60 2.20 0.00 54.80 2.20 57.00 С,На iC.Но 57.00 0.00 162.50 8.60 171.10 171.70 0.60 171.80 0.10 226.60 10.80 215.80 0.00 nCaH10 iC,Н12 226.60 227.30 0.70 28.10 0.00 28.10 0.00 11.90 28.10 40.00 17.50 17.50 0.00 17.50 0.00 nC3H12 C6* 16.10 33.60 0.00 0.00 0.00 205.30 0.00 0.00 205.30 175.50 445.50 270.00 56.00 Total 234.10 501.50 735.60