Mass Transfer Operations II — Winter 2022

Define: 1) Humid Volume 2) Humid heat 3) Lewis Relation

Explain effect of temperature on adsorption with one example.

Amixture of benzene and toluene containing 60 mole% benzene is to be separated to give a product of 95 mole% benzene and bottom product containing 10 mole% benzene. The feed enters a column at its bubble point. It is proposed to operate the column with reflux ratio of 2.5. Calculate number of theoretical plates needed by Mccabe-Thiele method and position of feed plate. The vapor liquid equilibrium data are given as below: x 0 0.05 0.1 0.2 0.3 0.4 0.5 y 0 0.13 0.21 0.375 0.5 0.6 0.7 x 0.6 0.7 0.8 0.9 1.0 y 0.77 0.83 0.9 0.95 1.0

Explain constant pressure equilibria with neat sketch.

Explain feed tray location in distillation operation.

Aliquid mixture containing 40 mole% methanol and 60 mole% water is fed to the differential distillation at atmospheric pressure with 60 mole% of the liquid is distilled. Find the composited distillate and the residue. Equillibrium Data: x 0.05 0.1 0.2 0.3 0.4 0.5 y 0.27 0.42 0.57 0.66 0.73 0.78

Aliquid mixture containing 60 mole% acetone (1), 40 mole% water (2) at 1 atm pressure in differentially distilled to vaporize 30 mole% of the feed. Compute the composition of composite distillate and residue. The VLE data are: x 0.01 0.05 0.1 0.2 0.4 0.5 y 0.253 0.625 0.755 0.815 0.839 0.849 x 0.6 0.7 0.8 0.9 0.95 y 0.859 0.874 0.898 0.935 0.9631

Define: 1) Relative saturation 2) Percentage saturation 3) Dew point

Explain principle and applications of steam distillation.

Derive equation for Adiabatic Saturation Curve.

Discuss range and approach with reference to cooling tower.

Explain Azeotropic distillation.

Explain the various types of cooling towers and discuss their selection criteria.

List assumptions of McCabe-Thiele method and its limitations.

Compare and contrast physical adsorption and chemisorptions.

Explain Ion Exchange and describe techniques and applications of ion exchange and list out the factors on which rate of ion exchange is dependent.

Define: 1) Total reflux ratio 2) Minimum reflux ratio 3) Quantity ‘q’.

Explain in brief on Pressure Swing Adsorption (PSA).

Explain Freundlich equation. Derive the relation for single stage adsorption using the Freundlich equation.

List types of distillation operation.

Explain rate of drying curve with neat diagram.

A 100 kg batch of granular solid containing 30% moisture is to be dried in a tray dryer to 16% moisture by passing a current of air at 350 K across its surface at a velocity of 1.8 m/s. If the constant rate of drying under these conditions is 0.7 x 10-3 kg/m2s and the critical moisture content is 15%. Calculate the drying time.

Draw schematic diagram of conventional fractionating column.

Explain principle and working of fluidized bed drier with neat sketch.

A 50 kg batch of granular solid containing 25% moisture is to be dried in a tray dryer to 12% moisture by passing a current of air at 363 K across its surface at a velocity of 1.8 m/s. If the constant rate of drying under these conditions is 0.0008 kg/m2s and the critical moisture content is 10%. Calculate the drying time. The surface area available for drying is 1.0 m2.