Question

1) Why is the column packing material used in the fractional distillation column? 2) What should be the characteristic features of an ideal column packing material? 3) Two fractional distillations are run with identical mixed samples of two liquids using different columns. In apparatus A, the column is 15 em long, and in apparatus B, the column is 25 cm long. Will one apparatus provide any better separation of the mixture then the other? If so which one and why? Name some important large-scale applications of fractional distillation. Why should a distillation apparatus never be fully sealed? what are azeotropic mixtures? State an important application of azeotropic distillation.

Answer 1

Frictional distilaction is employed to separate two or more liquids that's are miscible. The efficiency of fractional distillation depends on the use of the fractionating column. It provides a larges surface are for evaporation & condensation of the liquid mixture. Following characteristics: - cost: the cost of the packing materials should be very low. Surface area: A large interfacial area of contact is always recommended. Void volume: A high void volume is needed to maintain low pressure drop Apparatus B: if length of column is high then two identical mixed sample can be reputed. Because separation is done due to difference in boiling points of liquids. We know that is length of column is high then there are more temperature difference and can be easily separated. Application of frictional distillation separate crude oil into its different components. LPG & naphtha have lower boiling point then diesel & lubricating oil. Separating oxygen & nitrogen from air. Alcoholic beverage