This set of Unit Processes Multiple Choice Questions & Answers (MCQs) focuses on “Reactor Development”.
1. What is/are the application of German fixed-bed reactor?
a) Heat removal
b) Complex design
c) Low capacity
d) All of the mentioned
View Answer
Explanation: Germany employed a fixed bed of granular or extruded catalyst. In order to provide adequate cooling surface for heat removal, the reactors were of a complex design and of low capacity.
2. What is the drawback if German fixed-bed reactor?
a) Heat removal
b) High contact area
c) High cost
d) All of the mentioned
View Answer
Explanation: In German fixed-bed reactor, low output and complex fabrication, the fixed cost per unit of product was quite high. Other types of reactors were developed because of these inherent drawbacks.
3. Synthesis with a slurried catalyst has been investigated in which type of plants?
a) Small
b) Moderate
c) Large
d) None of the mentioned
View Answer
Explanation: Slurry, synthesis with a slurried catalyst has been investigated in large pilot plants.
4. What does slurry consists of?
a) Fine particles
b) Pulverized particles
c) Large particles
d) All of the mentioned
View Answer
Explanation: The slurry consists of finely pulverized catalyst particles suspended in a high-boiling oil to which the heat of reaction is transferred.
5. The oil-circulation process is similar to which process?
a) Slurry process
b) German fixed-bed process
c) Both of the mentioned
d) None of the mentioned
View Answer
Explanation: The oil-circulation process is similar to the slurry system in that the catalyst is submerged in a high-boiling oil which serves to remove the heat of reaction and permit close control of the temperature.
6. What is the size of particles in Oil circulation?
a) Fine particles
b) Moderate size
c) Large size
d) None of the mentioned
View Answer
Explanation: In oil circulation, larger catalyst particles are used, either granules or massive iron or steel such as shot or lathe turnings.
7. Which synthesis process is similar to catalytic cracking of hydrocarbons?
a) Slurry process
b) German fixed-bed
c) Oil circulation
d) Fluid bed process
View Answer
Explanation: Synthesis in a fluid bed of catalyst, in a manner similar to that employed for catalytic cracking of hydrocarbons.
8. What is meant by ‘Hot gas recycle’?
a) Removal of heat
b) Supplying heat
c) Reflux heat
d) None of the mentioned
View Answer
Explanation: In Hot-gas Recycle, removal of the heat of reaction as sensible heat of fresh feed and recycle gas is utilized in the hot-gas-recycle system.
9. The shape and size of catalyst is not very important.
a) True
b) False
View Answer
Explanation: The shape and size of the catalyst must be designed to avoid excessive pressure drop and high costs for circulating gas.
10. What happens to the velocity of gas, as heat-transfer coefficients increases?
a) Increases
b) Decreases
c) No change
d) None of the mentioned
View Answer
Explanation: As linear velocity of the gas is higher, greater heat-transfer coefficients are obtained.
11. Heat removal can only be done directly.
a) True
b) False
View Answer
Explanation: Heat removal for the most part may be considered to take place either directly, as in the oil- or gas-cooled systems where the catalyst surface .s in contact with the cooling medium, or indirectly, as in the fixed or fluid beds where heat must be transferred through the bed to a cooling surface.
12. What happens when the reaction occurs non-uniformly?
a) High gradient
b) Low gradient
c) Small yield
d) Less conversion
View Answer
Explanation: A uniform amount of reaction has been assumed through the catalyst bed. When the reaction occurs non uniformly and a large amount of conversion takes place in a limited area, as is often the case near the point of entry of the fresh gas, the gradients are higher.
13. Lower gradients ensure better temperature control.
a) True
b) False
View Answer
Explanation: Lower gradients ensure better temperature control and freedom from overheating.
Sanfoundry Global Education & Learning Series – Unit Processes.
To practice all areas of Unit Processes, here is complete set of 1000+ Multiple Choice Questions and Answers.
If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]
- Apply for Chemical Engineering Internship
- Check Unit Processes Books
- Check Chemical Engineering Books
- Practice Chemical Engineering MCQs
