A. 2
B. 0.5
C. 50
D. 150
Related Mcqs:
- Compound A is extracted from a solution of A + B into a pure solvent S. A Co-current unit is used for the liquid-liquid extraction. The inlet rate of the solution containing A is 200 moles of B/hr.m2 and the solvent flow, rate is 400 moles of S/m2. hr. The equilibrium data is represented by Y = 3X2 , where Y is in moles of a A/moles of B and X is in moles A/moles of S. The maximum percentage extraction achieved in the unit is_________________________?
A. 25%
B. 50%
C. 70%
D. 90% - In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions: (i) Reflux stream is completely liquid and is at its bubble point. (ii) Reflux stream is below its bubble point ?
A. Condenser and reboiler loads are the same in both the cases
B. Reboiler load is the same in both the cases but condenser load is higher in case (ii)
C. Condenser load is the same in both the cases but reboiler load is higher in case (ii)
D. Both condenser and reboiler loads are higher in case (ii) as compared to case (i) - In continuous distillation, the internal reflux ratio (Ri) and the external reflux ratio (Re) are related as_____________________?
A. Ri = Re/(1 – Re)
B. Ri = (1 – Re)/Re
C. Ri = Re
D. Ri = Re/(1 + Re) - The operating cost of a distillation column at minimum reflux ratio is____________________?
A. Minimum
B. Maximum
C. Infinite
D. Zero - An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii) ____________________?
A. Less number of trays are required
B. Composition of the residue remains unchanged
C. More number of trays are required but the residue composition remains unchanged
D. More number of trays are required and the residue composition is more dilute in methanol - 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 At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are being withdrawn and feed to the column is stopped).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 - For a fixed number of ideal stages in a distillation column, as the reflux ratio is increased, the difference in composition between the top and bottom product streams__________________?
A. Increases
B. Decreases
C. Remain unaffected
D. Passes through a maximum - Pick out the correct relationship. (Where, Ri = internal reflux ratio Ro = external reflux ratio.) ?
A. (1 + Ro) = Ro/Ri
B. (1 – Ro) = Ro/Ri
C. (1 + Ri) = Ro/Ri
D. (1 – Ri) = Ro/Ri - If Rm is the minimum reflux ratio, the optimum reflux ratio may be around _________________ Rm ?
A. 1.2 to 1.5
B. 2.5 to 3
C. 3 to 4
D. 5 - A distillation column separates 10000 kg/hr of a benzene-toluene mixture as shown in the figure below: In the figure xF, xD and xW represent the weight fraction of benzene in the feed, distillate and residue respectively. The reflux ratio is_______________ ?
A. 0.5
B. 0.6
C. 1.0
D. 2.0
