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3.4.1. Semi-regenerative fixed bed 
In this process, the catalyst regeneration implies unit shutdown. 
Feed
Reformate
Pretreatment
Reforming
Rectification
Stabilization
C
4
Purge
Purge
Se
p
ar
at
in
g
dr
u
m
Se
p
ar
at
in
g
dr
u
m
Figure B-3-1: Simplified scheme of semi-regenerative process for catalytic reforming
The pre-treatment section is necessary to purify the feed as catalyst is very sensitive to 
impurities such as nitrogen, sulfur and oxygenated compounds and metals. A molecular sieve 
can also be used in order to eliminate water traces. 
Hydrogen recycling (from the stabilization section) is necessary to prevent a rapid catalyst 
deactivation. 
Finally, light hydrocarbons produced are separated from the product in the stabilization 
section. 
 
3.4.2. Continuous Catalyst Regeneration reforming process 
 
Nowadays, units are generally Continuous Catalyst Regeneration (CCR) reforming process 
named octanizing
®
. The scheme of this process is quite similar to semi-regenerative process 
except that the catalyst bed is moving from one reactor to another, before regeneration and 
introduction back to the first reactor. The scheme below is a simplified representation of the 
catalyst circulation in reactors. 

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37
Lift gas
Regeneration
section
Catalyst
Feed
Effluent
Figure B-3-2: Continuous catalyst regeneration reforming 
 
Two different lift gases are usually used: hydrogen rich gas or nitrogen gas. These gases are 
recovered and recycled so are not effluents of the process.