1. What happens if we use a heater for eg. steam instead of a downtherm, in the fluidized bed for production of ethylene oxide?
a) Reactor may explode
b) Helps in better temperature control
c) Nothing will happen
d) Reaction might change
Explanation: Since the reaction is already highly exothermic, addition of heat will worsen the situation
2. What happens if there is no narrow tubes in the fluidized bed for the production of ethylene oxide?
a) Leads to less intermediate yield
b) Leads to maximum yield of reaction intermediate
c) No effect on the reaction
d) None of the mentioned
Explanation: Since the reaction is exothermic, it need to be controlled which is only possible in plug flow with the help of downtherm.
3. In the HCl oxidation process, a slurry of catalyst fines in aqueous HCl is injected into the bed as?
a) Feed
b) Coolant
c) For temperature control
d) All of the mentioned
Explanation: Slurry is therefore used as feed, as coolant and for proper temperature control.
4. What will happen if the concentration of naphthaquinone builds up in the fluidized bed for phthalic anhydride production?
a) Reaction will explode
b) Helps in temperature control
c) Acts as coolant
d) None of the mentioned
Explanation: Since the reaction is highly exothermic
5. Why is the liquid naphthalene fed through nozzles directly to the bottom of the reactor, in the fluidized bed for phthalic anhydride production
a) Liquid is immediately vaporized
b) Liquid is immediately cooled
c) Liquid is immediately solidified
d) None of the mentioned
Explanation: According to Graham and Way, the liquid vaporizes on injecting through nozzle.
6. In the reaction of naphthalene to phthalic anhydride, what is the intermediate formed?
a) Naphthaquinone
b) Nascent oxygen
c) Naphtha-quinine
d) None of the mentioned
Explanation: Based on the analysis, it was found that naphthaquinone is the reaction intermediate.
7. What are the by-products present in the HCl oxidation process?
a) Chlorine gas, water vapour
b) Ammonia gas
c) Chloroform
d) None of the mentioned
Explanation: Based on the analysis of the exit gases, it was found that chlorine gas and water vapour are also present with HCl.
8. Why was fluidized bed not used commercially for production of gasoline from natural gas?
a) Conversion was below par
b) Scale-up was difficult
c) Back-mixing
d) All of the mentioned
Explanation: Fluidized bed was not possible because of less conversion, scale up problem.
9. Why was conversion in the production of gasoline in fluidized bed was less?
a) Back-mixing and by-passing
b) Recycling
c) Regeneration
d) None of the mentioned
Explanation: Back-mixing and by-passing are undesirable for gasoline production.
10. What is the main reason for lower efficiencies in the commercial operations of synthetic reactions through fluidized beds?
a) Gas bypassing
b) Backing mixing
c) Bubble behaviour
d) all of the mentioned
Explanation: Serious gas by-passing, back mixing and irregular bubble behaviour leads in lowering the efficiencies in fluidized beds.