Question

Q/ Why the efficiency of batch distillation process should be decrease?

Answer 1

In batch distillation we use a column equivalent to a number of equilberium stage is used.

as in the case of simple distillation a fixed quantity of liquid is charged to the still. During distillation the vapour passes through the column. The vapour condensed to the liquid at the top of the column. Nothing is added or withdrawn untill the run is complete.

Thus in each step more distillate condensed from vapour phase to liquid form . And in the mixture concentration of more volatile component will decrease with time.