Engineering Questions with Answers - Multiple Choice Questions

# Separation Processes MCQ’s – Binary Batch Distillation

1 - Question

What is fixed for a column of given diameter?
a) Feed rate
b) Boiling point
c) Molar vapor boilup rate
d) Molar flow rate
Explanation: The molar vapor boilup rate is fixed for a column of a given diameter.

2 - Question

For a batch rectifier, R=1, Boilup rate = 100mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 1 hr
b) 2 hr
c) 3 hr
d) 4 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 1hr

3 - Question

For a batch rectifier, R=2, Boilup rate = 50mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 1 hr
b) 2 hr
c) 3 hr
d) 4 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 3hr.

4 - Question

For a batch rectifier, R=1, Boilup rate = 50mol/hr
Moles of liquid residue at start W0=70
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 0.6 hr
b) 0.8hr
c) 1 hr
d) 0.9 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 0.8hr

5 - Question

For a batch rectifier, R=1, Boilup rate = 100mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 80
Calculate time required for batch rectification.
a) 0.2 hr
b) 0.4hr
c) 0.6 hr
d) 0.8 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 0.2hr.

6 - Question

For a batch rectifier, R=1, Boilup rate = 100mol/hr
Moles of liquid residue at start W0=200
Moles of liquid residue at end W= 100
Calculate time required for batch rectification.
a) 1 hr
b) 2 hr
c) 3 hr
d) 4 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 2hr.

7 - Question

For a batch rectifier, R=4, Boilup rate = 100mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 1 hr
b) 2 hr
c) 2.5 hr
d) 3 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 2.5hr.

8 - Question

For a batch rectifier, R=1, Boilup rate = 200mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 0.2 hr
b) 0.21 hr
c) 3 hr
d) 0.25 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 0.25hr.

9 - Question

For a batch rectifier, R=1, Boilup rate = 20mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 3 hr
b) 4 hr
c) 5 hr
d) 6 hr

Explanation: Since the time required for batch distillation is given by t= (R+1)/V*(Wo-Wt), t= 5hr.

10 - Question

For a batch rectifier, R=1, Boilup rate = 70mol/hr
Moles of liquid residue at start W0=100
Moles of liquid residue at end W= 50
Calculate time required for batch rectification.
a) 1.3 hr
b) 1.42 hr
c) 3 hr
d) 2.5 hr