Mass Transfer Operation - II — Summer 2019

Write a short note on types of reflux ratio.

Discuss positive deviations from ideality with neat sketch.

Derive the equation of adiabatic saturation curve.

Discuss applications of steam distillation.

Write in brief about Azeotropic distillation.

Aliquid mixture of 50 mole% n-heptane (i) and 50 mole% n-octane (ii) were subjected to differential distillation at atmospheric pressure with 55 mole% of the liquid distilled. Compute the composition of the composite distillate and the residue. “x” 1.00 0.50 0.46 0.42 0.38 0.34 0.32 0.00 “y” 1.00 0.689 0.648 0.608 0.567 0.523 0.497 0.00

Afractionation column has been installed to distillate 5000 kg/hr of a mixture of 50 % methanol & 50% water (by weight). The overhead and bottom products are found to contain 95 % methanol and 1 % methanol respectively. Carry out material balances. Data: Mol. wt. of methanol: 32 and Mol. wt. of water: 18.

Write a note on flash distillation.

With reference to Raoults’s law, explain characteristics of ideal solutions.

Define quantity ‘q’. Derive equation for q-line and discuss location of ‘q’ line for typical feed conditions in brief.

Discuss importance of vacuum distillation.

Explain the following terms:

Bound moisture ii) Free moisture iii) Equilibrium moisture iv) Critical moisture

Write Freundlich equation. How is it applied to two-stage cross current adsorption?

Explain Adsorption hysteresis.

Write a note on drying at low temperature.

Explain construction, working, advantages & disadvantages of tray dryer.

Write applications of rotary drier.

Explain rate of drying curve with neat diagram.

What do you mean by Ion Exchange? Describe techniques and applications of ion exchange and list out the factors on which rate of ion exchange is dependent.1

Explain relative volatility and its relationship with vapor pressure.

Qualitatively, explain the apparent adsorption of solute from concentrated solution.

Derive the equation for the rate of adsorption in a fixed bed and explain the concept of degree of saturation

Explain nature of adsorbents.

Write down the assumptions of McCabe-Thiele method.

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