For the same feed, feed quality and separation (in a distillation column), with the increase of total pressure, the number of ideal plates will_____________________?

Related Mcqs:

1. A distillation column with N plates is being operated under normal conditions. At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are being withdrawn and feed to the column is stopped). At the new steady state ?

   A. Composition of vapors and that of liquid do not vary throughout the column
   B. Reboiler load and condenser load are minimum
   C. The top and bottom compositions are unchanged with and without total reflux
   D. The top and bottom compositions correspond to the maximum enrichment available

2. The minimum number of theoretical plates is required for achieving a given separation in distillation column with_________________?

   A. No reflux
   B. Total reflux
   C. Zero reflux ratio
   D. Minimum reflux ratio

3. On moving the feed line (q-line) from saturated liquid feed (vertical position) to saturated vapor feed (horizontal feed), if the slope of both the operating lines are to be increased, then it will result in______________________?

   A. Greater degree of separation with a fixed number of trays
   B. Increased reboiler load
   C. Increased reflux ratio
   D. None of these

4. According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B ? Assume that relative volatility (αAB = 2) does not change appreciably in the column ?

   A. 5
   B. 9
   C. 12
   D. 28

5. When the feed to a distillation column is a saturated liquid, slope of the feed line is_____________________?

   A. Zero
   B. Unity
   C. Infinity
   D. None of these

6. The feed to fractionating column is changed from saturated vapour to saturated liquid. If the separation and reflux ratio remains unchanged, the number of ideal stages will______________________?

   A. Increase
   B. Decrease
   C. Remain same
   D. Depend on saturated boiling point; may increase or decrease

7. At what value of reflux ratio, number of theoretical plates in a distillation column is minimum ?

   A. 0
   B. 1
   C. ∞
   D. < 1

8. Fenske-Underwood equation used for calculating the minimum number of theoretical plates in distillation column is valid for_________________?

   A. Constant molal overflow
   B. Total reflux
   C. Constant relative volatility
   D. All A., B. and C.

9. The-relative volatility for separation of a non-ideal binary mixture by distillation should be ___________________?

   A. 0
   B. 1
   C. > 1
   D. < 1

10. In a binary distillation column, if the feed contains 40 mole % vapour, the q line will have a slope of_________________?

    A. 1.5
    B. -0.6
    C. -1.5
    D. 0.6