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3.2.1. Naphtha feed 
The feed of the catalytic reforming unit is the heavy naphtha from the crude distillation. It 
often goes through the hydrotreating unit before reforming in order to get naphtha free from 
sulfur, nitrogen and olefins. Catalytic reforming naphtha feed contains C
5
to C
10
paraffins, 
naphtenes and aromatics.
Also, gasolines from visbreaking, coking, hydrocracking or fluid catalytic cracking (FCC) 
units can be sent to reforming. 
The following table indicates the characteristics of two typical charges in weight percent. 
. 
Paraffins 
Naphtenes 
Aromatics 
Charge A 
C
5
C
6
C
7
C
8
C
9
C
10
Total 
- 
5.49 
16.83 
21.38 
17.26 
2.59 
63.55 
- 
2.30 
5.80 
8.27 
5.95 
0.63 
22.95 
- 
0.41 
3.18 
6.80 
3.08 
- 
13.47 
Charge B 
C
5
C
6
C
7
C
8
C
9
C
10
Total 
0.16 
3.31 
6.13 
9.79 
3.89 
3.59 
26.81 
0.27 
5.78 
14.24 
14.47 
17.14 
11.17 
63.07 
- 
0.20 
1.20 
3.54 
4.29 
0.88 
10.10 
Table B-3-1: Typical properties of two charges for catalytic reforming unit 

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3.2.2. Catalyst 
Catalysts used are bimetallic platinum - rhenium (Pt/Re) or platinum – tin (Pt/Sn) catalysts. 
Pt/Re is mostly used for semi-regenerative process and Pt/Sn for circulating bed process. 
Reforming catalysts activate many different reactions. However, they are very sensitive to 
impurities and require the feed pre-treatment. Another drawback is that these catalysts 
produce coke at a non negligible speed. This speed can nevertheless be reduced with high 
pressure of hydrogen. 
3.3. Products characteristics 
Catalytic reforming generates three main products: reformate stream, hydrogen rich gas 
stream and LPG stream. There is also a by-product which is a fuel gas stream from the LPG 
absorber. 
3.4. Reaction section 
Reactions occurring in catalytic reforming are numerous. Desired reactions are: 
- Dehydrogenation 
+ 3 H
2
- Isomerization/dehydrogenation 
+ 3 H
2
- Parrafins isomerization 
n
-C
7
H
16
i
-C
7
H
16
- Dehydrocyclization 
n
-C
7
H
16
+ 4 H
2
Other parasite reactions are promoted with the catalyst. These reactions are dismutation, 
alkylation, hydrocracking, hydrodealkylation and coking.
Different technologies exist for catalytic reforming. These differences concern mainly the 
reactor type: the catalytic bed can be either fixed or mobile. With fixed bed, two processes 
exist: semi-regenerative or cyclic. With a mobile bed, a continuous process is proposed by 
Axens. Simplified process schemes and basic information are given below. 

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