Enriching tower for benzene and toluene -

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Textbook Problem 26.4-7 Enriching Tower for Benzene-Toluene An enriching tower is fed 100kgmol/h of a saturated vapor feed containing a 40mol% benzene (A) and 60 mol\% toluene (B) at 101.32kPa abs. The distillate is to contain 90mol% benzene. The reflux ratio is set at 4.0:1. Use the McCabe-Thiel distillation method to calculate the kgmol/h distillate D and bottoms W, and their compositions. Also, calculate the number of theoretical plates required. Ans. D=20kgmol/h,W=80kgmol/h,xw=0.275