1. University of Boumerdes Algeria
Mimoun. Hadj and Boukhemkhem. Ali
University of Boumerdes Algeria  :

2. Aromatic hydrodecyclization of using catalysts based on molybdenum and tungsten supported on the Remblend of Kaolin( local clay based on bentonite)

3. Abstract our interest is
what is the news of the study? What is the interest?
our interest is
eliminate the harmful effects of sulfur (reduce air pollution sulfur)
improve quality for the recovery of the oil products
what guidance track?
synthesizing a catalyst ensuring to :
open aromatic cycles
reduce the aromatic content in fuels.
Reduce the sulfur content in products
the work is structured in three steps
1-preparation and characterization of catalysts 2- use of catalysts prepared in the method craking 3-analyzes of the products obtained and discution

4. 1-Introduction.
The very stringent specifications are adopted in several countries to minimize the negative harmful exhaust emissions impact.
Reducing the concentration of the sulfur content of the polycyclic aromatic compound in oils and diesel fuels.
The high and exigent demand for diezel refiners requires increased recovery of aromatic fractions from the catalytic cracking process using novel catalysts which provide aromatic hydrogenation followed by selective ring opening of naphthenes.

5. 1.Introduction.
The study consist of the valorization of petroleum fractions rich on polyaromatics diesel fuel using clay catalysts. is based on the change in the content of aromatics in terms of temperature, under constant hydrogen pressure
preparation and characterization of catalysts
This part is based on the preparation of two catalysts from the Kaolin Remblend.
The first is monometallic, consisting of molybdenum Mo / Kaolin.
second bimetal is composed of tungsten and molybdenum Mo-W / Kaolin .

6. 1-Introduction.
The kaolin used is subjected to physical-chemical analyzes to determine the mineralogical composition and physical-chemical and mechanical properties of the clay.
2-catalytic test performed on the prepared catalysts
The second is to develop the petroleum fractions containing high levels of polyaromatic diesel fuel by the methods of déshydrodécyclisation aromatics using a vast catalysts prepared.

7. Introduction.
A third part is devoted to the chromatographic analysis of products to develop the conversion and selectivity of catalysts .

8. 2. Experimental
A series of analysis was performed to characterize the natural clay used as carrier for catalysts.
2.1. Infrared spectroscopy Analys
Figure 1 : Infrared spectrum of natural Kaolin Remblend

9. 2. Experimental
According the FTIR spectrum, the following bands are observed:
Cm-1: Broad band attributed to hydroxyl groups OH.
Cm-1: Assigned to the vibration of the water molecule.
Cm-1: Denotes the elongation of the vibration of Si-O-Al bond.
1095 Cm-1: Denotes the elongation of the Si-O bond.
540 Cm-1: Characterize the elongation of the Al-O-OH bond.
913 Cm1: Characterize the elongation of the Al-OH bond.
570 Cm-1: characteristic of the Si-O deformation binding [4]

10. 2. Experimental 2.2. Mineralogical structure of the kaolinite
Mineralogical analysis was Scanning electron microscope PHILIPSE FX30. kaolin structure is shown below in figure 2

11. Figure 2 : MEB Image of natural kaolin Remblend

12. 2. Experimental
The kaolinites are minerals clay formed by stacking sheets identical, of type 1: 1 of structural formula Si2Al2O5(OH)4.
 2. 3. Determination of the chemical composition.
Data analysis of fluorescence X (XRF) is given by table 1
table 1: Chemical composition of kaolin Remblend.

13. 2. Experimental

14. Figure 4 : Steps of catalysts preparation
Draying Kaolin
Filtration and washing
impregnating the activated Kaolin by metal salts drying in an ovenat 180°C
Air drying calcination analys and test catalysis
Acide activation of Kaolin(HCl)
Air drying
Formatting

15. Figure 5 : FTIR spectrum of the prepared catalysts

16. 3.1. Characterization of the catalysts used
Analysis by infrared spectroscopy  
The catalysts obtained are characterized by infrared spectroscopy, the spectra obtained for the two catalysts have the same general shape, the observed bond are:
Cm-1: Broadband attributed to hydroxyl groups OH.
Cm-1: Assigned to the vibration of the water molecule.
Cm-1: Denotes the elongation of the vibration of Si-O-Al bond.
Cm-1: Denotes the elongation of the Si-O bond.
Cm-1: Denotes bands metal oxides.
913 Cm-1: Characterize the elongation of the Al-OH bond
570 Cm-1 : characteristic of the Si-O deformation [10] binding

17. 3.1.2. Analysis by electron microscopy (SEM)

18. Analys material 3-analyzes of the products obtained and discution
The product used is the average aromatic, resulting from the process of aromatic extraction contained in the basic oils. We study the elemental composition of paraffins, olefins, naphthenes and aromatics, for that chromatographic analysis were performed by gas chromatography (GC).
we are only interested by: P, O, N, A.
The operating conditions :
The catalyst was tested at different temperatures
  at 450, 470, 490 and 540°C.
* Space velocity PPH = 2h-1.
* Hydrogen pressure = 6 bar

19. Resultats

21. discusion
Catalytic tests performed on hydrodecyclization reactions of aromatics contained in the medium aromatic extract, led to the following results:
The Bimetallic catalyst (MoO3-WO3 / Kaolin) is more active than monometallic.
Under a pressure of 6 bar hydrogen, increases temperature leads to the formation of products derived from aromatic hydrocyclisation, but beyond the temperature of ° C the cracking reaction are predominate.
Both catalysts show good activity for mercaptans.
The deposit of coke on the two catalysts becomes increasingly significant with increasing temperature, this coke poisons the catalysts.