ANS:B - moving bed

The Thermofor catalytic cracking process is a moving bed process.

Explanation:

• Thermofor Catalytic Cracking (TCC): This is a process used in petroleum refining to convert heavy hydrocarbons into lighter fractions such as gasoline and diesel. It involves the use of a catalyst to facilitate the cracking reaction.

Characteristics of the Thermofor Process:

• Moving Bed: In the TCC process, the catalyst particles move through the reactor and regenerator in a continuous cycle. This contrasts with fixed bed processes, where the catalyst remains stationary, and fluidised bed processes, where the catalyst particles are suspended and behave like a fluid.
• Catalyst Movement: In the TCC process, the catalyst particles move down through the reactor under gravity and are then transported to the regenerator, where they are regenerated by burning off the accumulated coke. The regenerated catalyst is then returned to the reactor.