Mimoun. Hadj and Boukhemkhem. Ali
University of Boumerdes Algeria
Email : mimounhadj@yahoo.fr
Aromatic hydrodecyclization of using
catalysts based on molybdenum and
tungsten supported on the Remblend of
Kaolin( local clay based on bentonite)
Abstract
•
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
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.
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 .
1-Introduction.
The kaolin used is subjected to physicalchemical analyzes to determine the
mineralogical composition and physicalchemical 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.
Introduction.
• A third part is devoted to the
chromatographic analysis of products to
develop the conversion and selectivity of
catalysts .
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
40
%T
35
30
25
20
15
10
5
4000
3500
3000
2500
2000
1750
1500
1095,57
1384,89
0
1250
1000
750
500
1/cm
2. Experimental
•
•
•
•
•
•
•
•
According the FTIR spectrum, the following bands are observed:
3400-3500 Cm-1: Broad band attributed to hydroxyl groups OH.
1630-1700 Cm-1: Assigned to the vibration of the water molecule.
752-789 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]
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
Figure 2 : MEB Image of natural kaolin
Remblend
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.
2. Experimental
Figure 4 : Steps of catalysts
preparation
• Draying Kaolin
Acide activation of Kaolin(HCl)
Filtration and washing
Air drying
•Formatting
impregnating the activated Kaolin
by metal salts
drying in an ovenat 180°C
•
Air drying
calcination
analys and
test catalysis
•
Figure 5 : FTIR spectrum of the prepared
catalysts
30
%T
25
20
15
10
459,06
5
4000
3500
3000
2500
2000
1750
1500
1091,71
1384,89
0
1250
1000
750
500
1/cm
3.1. Characterization of the catalysts used
• 3.1. Characterization of the catalysts used
• 3.1.1. 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:
• 3400-3500 Cm-1: Broadband attributed to hydroxyl groups OH.
• 1630-1700 Cm-1: Assigned to the vibration of the water molecule.
• 752-789-803 Cm-1: Denotes the elongation of the vibration of Si-OAl bond.
• 1095-1171 Cm-1: Denotes the elongation of the Si-O bond.
• 500-450 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
3.1.2. Analysis by electron microscopy (SEM)
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
Resultats
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
490 ° 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.