A saturated liquid feed of 750 kmol/h consists of 20 mol% propane, 35 mol% n-butane and 45 mol% n-hexane. A distillate recovery of 98 mol% n-butane and bottoms recovery of

99 mol% n-hexane is desired. \text { The average relative volatility is } \alpha_{\text {propane-butane }}=2.04 \alpha_{\text {butane-butane }}=1.00 \mathrm{and} \alpha_{\text {hexane-butane }}=0.2 Constant molar overflow (CMO) is valid. Reflux is returned as a saturated liquid. The column has a partial reboiler and a total condenser. Calculate the total vapour flow rate in the enriching section at minimum reflux (Vmin) in kmol/h D = 410.625 kmol/h \phi=0.3197 \text { [Trial and Error] }