An advanced method of distillation in chemical engineering

Azeotropic distillation is carried with the addition of the entrainer in the solution. Entrainer addition leads to the formation of the ternary azeotrope in the solution which facilitates the distillation of the compound. Entrainer works by affecting the volatility of one of the components of the solution.

The best known example of entrainer is benzene and cyclohexane added to water/ethanol azeotropicmixture in order to form a azeotrope that will facilities the distillation process.

The most common example of this type of distillation column is the separation of ethanol.

The distillation of ethanol takes place with the concentration of eth ethanol and water solution to 90% concentrated solution of ethanol

The entrainer, n-pentane is added to the feed column to form a ternary azeotrope in the column which enhances the separation of the ethanol from the solution. The formation of ternary azeotrope forms a two phase in the solution.

The two separate phase present in the solution comprises of an organic phase which remains at the top of the column and the lower heavy phase which is expelled out of the column as crude ethanol.

The entire process is carried at a temperature of 32°C and pressure of 1 bar.

Azeotriopic distillation is commonly employed in three different forms

Matrial Separating Agent : Agent used in the distillation process is entrainer.

Pressure-swing distillation: It is based on the varying pressure and activity coefficient of the solvent.

Molecular sieves: It is commonly used to remove water form eth given sample.