QUESTION $1$

Table $1$ shows the vapor$-$liquid equilibrium data for the Secunda distillation unit aimed at separating a mixture containing $50$mol$\%$ of benzene and balance toluene. The feed mixture enters the distillation unit at its bubble point to the optimal plate. The distillation unit is to produce a $453\mathrm{.}65k\frac{g}{h}r$ distillate stream containing $95$mol$\%$ benzene and a bottoms stream containing $95$mol$\%$ toluene.

Table $1$: Vapor$-$liquid equilibrium data $(1$ atm, mole fraction benzene$)$

$\backslash$table$[[x,0,0\mathrm{.}1,0\mathrm{.}2,0\mathrm{.}3,0\mathrm{.}4,0\mathrm{.}5,0\mathrm{.}6,0\mathrm{.}7,0\mathrm{.}8,0\mathrm{.}9,1\mathrm{.}0],[y,0,0\mathrm{.}21,0\mathrm{.}37,0\mathrm{.}51,0\mathrm{.}64,0\mathrm{.}72,0\mathrm{.}79,0\mathrm{.}86,0\mathrm{.}91,0\mathrm{.}96,1\mathrm{.}0]]$

Draw a diagram representing the process

$(4)$

Perform the material balance on the distillate and bottoms streams in kmo$\frac{l}{h}r$

$(8)$

Determine the minimum number of equilibrium stages needed to carry out the desired separation

Calculate the minimum reflux ratio

$(5)$

Determine the number of actual stages needed, using a reflux ratio $($L$\text{'}/$D$)$ of $50\%$ more than the minimum

$(8)$

$[30$ Marks$]$