3of13
(2.1) where is the moles of initial charge feed of composition and Boilu V.y W is the moles of residual liquid at the end of distillation of Condenser composition. The batch distillation process is shown here Distillate schematically. In equation, Eqn 2.1y=yis the instantaneous -D.p Still On pot with the residual liquid composition x(=in the pot. The instantaneous vapor-liquid equilibrium (VLE relationship between vapor and liquid phases for the more volatile component A of a binary mixture is given as: 3x y= (2.2) 1+2x a. Using VLE relationship of Eqn.2.2, integrate Eqn 2.1 and show that the resulting equation upon integration may be written as: n W =In (2.3) W. V1-xx b. Now consider the differential batch distillation of 100 mol of a binary liquid mixture (feed that contains 30 mol% A and the balance is B. You terminate your differential batch distillation operation when the residue composition drops to 20 mol% of A in the Still pot. Determine the amount of total distillate collected and its average composition in mol fraction of A.
