$4$EE$10.$ A distillation column with total condenser and partial reboiler is used to separate ethanol and acetone. The reflux is saturated liquid and CMO is valid. A $90$ mole $\%$ Acetone purity is desired in the distillate and $10$ mole $\%$ purity in the bottoms stream. The feed has a quality of $0\mathrm{.}5$ and is $50$mole$\%$ Acetone.

$($a$)$ How many stages are required at total reflux?

$($b$)$ What is the minimum reflux ratio?

$($c$)$ If you operate a reflux ratio that is twice the minimum reflux ratio, how many stages are needed to achieve the desired separation? What is the optimum feed stage?

Acetone $/$ Ethanol at $14\mathrm{.}70$ psia By UNQC