An equimolar liquid mixture of benzene and toluene is separated into two products streams by distillation. a process flowchart and somewhat oversimplified description of what happens in the process above. inside the column a liquid stream flows downward and a vapor stream rises. at each point in the column some of the liquid vaporizes and some of the vapor condenses. the vapor leaving the top of the column which contains 97 mole% benzene is completely condensed and split into two equal fractions: one is taken off as the overhead product stream and the other (the reflux) is recycled to the top of the column. the overhead product stream contains 89.2% of the benzene fed to the column. the liquid leaving the bottom of the column is fed to a partial reboiler in which 45% of it is vaporized. the vapor generated in the reboiler (the boil up) is recycled to become the rising vapor stream in the column and the residual reboiler liquid is taken off as the bottom product stream. the composition of the streams leaving the reboiler are governed by the relation
[yb/(1-yb)]/[xb (1-xb)] =2.25
where yb and xb are the mole fractions of benzene in the vapor and liquid streams respectively.
a) draw and label flow diagram ( don't do dof)
b) write in order the equations you solve to determine all unknown variables on the flow chart circling the variables for which you would solve in each equation ( don't do calculation)
c) calculate the molar amounts of the overhead and bottom product the mole fraction of benzene in the bottom product and the percentage recovery of toluene in the bottoms product ( answer : xb=0.100 Mol B /Mol
moles of the overhead =46.0 mole ,, moles of bottoms =54.0 moles
recovery of toluene =97%)