CA2815618A1 - Method for converting hydrocarbon feedstock comprising a shale oil by hydroconversion in an ebullating bed, fractionation by atmospheric distillation and liquid/liquid extraction of the heavy fraction - Google Patents

Abstract

A hydrocarbon feed conversion process comprising a shale oil comprising a boiling bed hydroconversion stage, a fraction fraction fractionated by atmospheric distillation in a light fraction, a naphtha fraction, a gas oil fraction and a heavier fraction than the diesel fraction, a liquid / liquid extraction step of the heavier fraction than the diesel fraction, and a hydrotreatment dedicated to each of the naphtha and diesel fractions. The process aims to maximize the yield of fuel bases.

Description

PROCESS FOR CONVERTING HYDROCARBONATED LOAD
COMPRISING HYDROCONVERSION SCHIST OIL
IN BOILING BED, FRACTIONATION BY DISTILLATION
ATMOSPHERIC AND LIQUID / LIQUID EXTRACTION OF
HEAVY FRACTION
The invention relates to a method for converting loads hydrocarbons comprising a shale oil in products more light, recoverable as fuels and / or raw materials for petrochemicals. More particularly, the invention relates to a method for converting hydrocarbon feedstocks comprising an oil of shale comprising a step of hydroconversion of the bed load bubbling, followed by a fractionation step by distillation atmospheric light fraction, naphtha, diesel and in a fraction heavier than the diesel fraction, a liquid / liquid exaction stage of the heavier fraction than the diesel fraction, and a hydrotreatment dedicated to each of the naphtha and diesel fractions. This process allows convert shale oils into fuel base of very good quality and aims in particular for excellent performance.
Given the high volatility of the price of a barrel and a decrease in discoveries of conventional oil fields, the oil companies are turn to unconventional sources. Alongside the sands and deep offshore oil shale, although relatively unknown, are more and more coveted.
Oil shales are sedimentary rocks containing an insoluble organic substance called kerogen. By In-situ or ex-situ heat treatment (retorting according to Anglo-Saxon terminology) in the absence of air at temperatures between 400 and 500 C, these schists release an oil, the oil shale, the general appearance of which is that of crude oil.
Although of different composition of crude oil, the oils of shale can be a substitute for the latter and also a source of chemical intermediates.
Shale oils can not substitute directly crude oil applications. Indeed, although these oils in some ways resemble oil (for example by a ratio of H / C similar), they are distinguished by their chemical nature and by

2 a content of metallic and / or non-metallic impurities much more important, which makes the conversion of this resource no conventional more complex than oil. The oils of shale have, in particular, oxygen and nitrogen higher than oil. They may also contain higher concentrations of olefins, sulfur or compounds metal (including arsenic).
Shale oils obtained by pyrolysis of kerogen contain many olefinic compounds resulting from cracking, which implies an additional demand for hydrogen in the refining. Thus, the bromine index, which makes it possible to calculate the concentration by weight of olefinic hydrocarbons (by addition of bromine on the ethylenic double bond), is generally greater than 30g / 100g load for shale oils, while it is between 1 and 5g / 100g charge for oil residues. Compounds olefins resulting from cracking consist essentially of mono olefins and diolefins. The unsaturations present in olefins are a potential source of instability by polymerization and / or oxidation.
The oxygen content is generally higher than in the heavy crudes and can reach up to 8% by weight of the load. The oxygenates are often phenols or acids carboxylic. As a result, shale oils may exhibit marked acidity.
The sulfur content varies between 0.1 and 6.5% by weight, requiring severe desulphurisation treatments in order to reach the specifications of fuel bases. The sulfur compounds are under form of thiophenes, sulphides or disulfides. In addition, the profile of Sulfur distribution within a shale oil may be different from that obtained in a conventional oil.
The most distinctive feature of shale oils is nevertheless their high nitrogen content, which makes them unsuitable as the conventional load of the refinery. Oil contains general rule around 0.2% by weight of nitrogen whereas raw shale generally contain from 1 to about 3%
by weight or more of nitrogen. In addition, the nitrogen compounds present in oil are usually concentrated in the boiling ranges

3 higher than the nitrogen compounds present in the oils of Raw shale is usually distributed across all ranges boiling of the material. Nitrogen compounds in petroleum are predominantly non-basic compounds, whereas generally the about half of the nitrogen compounds present in shale oils brutes is basic in nature. These basic nitrogen compounds are particularly undesirable in refining loads as these compounds often act as catalyst poisons. More, product stability is a problem that is common to many many products derived from shale oil. Such instability, including photosensitivity, appears to result essentially from the presence of nitrogen compounds. Therefore, shale oils brutes must generally be subjected to a treatment of severe refining (high total pressure) to obtain crude oil synthetic or fuel-based products respecting the specifications in force.
Similarly, it is known that shale oils may contain many trace metal compounds, usually present as organometallic complexes. From metal compounds, mention may be made of conventional contaminants such as nickel, vanadium, calcium, sodium, lead or iron, but also metal arsenic compounds. Indeed, the oils of shale may contain an amount of arsenic greater than 20 ppm while the amount of arsenic in crude oil is usually in the area of ppb (parts per billion). All these compounds Metallic poisons are catalysts. In particular, they irreversibly poison hydrotreatment catalysts and hydrogenation by gradually depositing on the active surface.
The classical metal compounds and some of the arsenic are are found mainly in heavy cuts and are eliminated by depositing on the catalyst. On the other hand, when the products containing arsenic are able to generate volatile compounds, these can be found partly in lighter cuts and can, therefore, poison the catalysts of subsequent processing, during refining or in petrochemicals.
In addition, shale oils generally contain sandy sediments from oil shale deposits

4 from which shale oils are extracted. These sandy sediments can create clogging problems, especially in fixed bed reactors.
Finally, shale oils contain waxes that give a pour point higher than the ambient temperature, preventing their transport in oil pipelines.
Due to considerable resources, and their evaluation as a promising source of oil, there is a real need to convert shale oils into lighter products, recoverable as fuels and / or raw materials for the petrochemicals. Shale oil conversion processes are known. Conventionally, the conversion is done either by coking or by hydroviscoreduction (thermal cracking in the presence of hydrogen), or by hydroconversion (catalytic hydrogenation). We also knows processes of liquid / liquid extraction.
Thus, patent US4483763 describes a conversion process shale oils to reduce their nitrogen content. This process includes a partial hydrogenation step followed by a step liquid / liquid extraction with a mixture of a polar solvent organic, an acid and water. The extraction is done either on a cut middle distillates (400-680 F = 204-360 C), ie all the effluent obtained by hydrogenation.
US5059303 discloses a method of converting oils of shale comprising a boiling bed hydroconversion stage or fixed bed, an optional fractionation step, a step liquid / liquid extraction of a liquid fraction or all the liquid effluent with a solvent for extracting the aromatics condensed. The raffinate obtained after evaporation of the solvent is then subject to fractionation to obtain a distillate fraction means containing up to 1000 ppm nitrogen and a fraction heavy containing 500 to 3000 ppm nitrogen. The patent US5059303 also describes a variant of the method comprising a step boiling bed hydroconversion, a separation step gas / liquid without pressure reduction, an extraction step liquid / liquid of the liquid phase and a step of hydrotreatment of the gas phase.

Object of the invention The specificity of shale oils being to have a certain number of metallic and / or non-metallic impurities makes the conversion of this unconventional resource much more complex

5 that that of oil. The challenge for the industrial development of shale oil conversion processes is therefore the need to develop processes adapted to the load, making it possible to maximize the yield of good quality fuel bases. Treatments known petroleum refining systems must therefore be adapted to the specific composition of shale oils.
The present invention aims at improving the known methods of conversion of hydrocarbon feeds comprising an oil of shale, notably by increasing the yield of fuel bases for a combination of steps having a specific sequence, and a treatment adapted to each fraction resulting from shale oils. Of The object of the present invention is also to obtain good quality having in particular a low sulfur, nitrogen and arsenic preferably respecting the specifications. Another objective is to propose a simple process, that is to say with the least necessary steps, while remaining effective, investment costs.
In its widest form the present invention is defined as a hydrocarbon feed conversion process comprising at least one shale oil having a nitrogen content at least 0.1%, often at least 1% and very often at least 2% by weight, characterized in that it comprises the following stages:
a) the load is treated in one section hydroconversion in the presence of hydrogen, the said section comprising at least one bubbling bed reactor operating at upward flow of liquid and gas and containing at least one supported hydrotreatment catalyst, b) the effluent obtained in step a) is sent, at least in partly, and often entirely, in a fractionation zone at from which an atmospheric distillation gaseous fraction, a naphtha fraction, a diesel fraction and a heavier fraction than the diesel fraction, WO 2012/08540

6 PCT / FR2011 / 053020 (c) the naphtha fraction is treated, at least in part, and often in total, in a hydrotreating section in presence of hydrogen, said section comprising at least one fixed bed reactor containing at least one catalyst hydrotreating, d) said diesel fraction is treated, at least in part, and often in whole, in another hydrotreatment section in the presence of hydrogen, said section comprising at least one fixed bed reactor containing at least one catalyst hydrotreating, (e) the heavier fraction than the diesel fraction is subjected to a liquid / liquid extraction in order to obtain a raffinate and an extract.
Usually, the treatment section of step a) comprises from one to three, preferably two reactors in series and the processing section of steps c) and d) also includes a to three reactors in series.
The research work carried out by the applicants on the conversion of shale oils led to the discovery that, so surprisingly, an improvement of the existing processes in terms of fuel efficiency and purity of products is possible by a combination of different stages, chained in a specific way, and a subsequent processing section for each fraction obtained from the process.
The first step involves hydroconversion into bed bubbly. The bubbling bed technology allows, compared to fixed bed technology, to handle loads heavily contaminated with metals, heteroatoms and sediments, such as shale oils, while exhibiting conversion rates generally above 50%. Indeed, in this first step, shale oil is transformed into molecules allowing for generate future fuel bases. Most of the metal compounds, sediments and compounds heterocyclic is removed. Effluent leaving the bubbling bed contains the most refractory nitrogen and sulfur compounds, and possibly volatile arsenic compounds found in lighter components.

7 The effluent obtained in the hydroconversion stage is then fractionated by atmospheric distillation to obtain different fractions for which a specific treatment to each fraction is done afterwards. The key step of the process consists in carrying out a fractionation by distillation before the liquid / liquid extraction stage, in order to to separately maximize the lighter fractions (naphtha, diesel), subsequently requiring a moderate hydrotreatment treatment and adapted to each fraction, and to minimize the heavier fraction that the diesel fraction, requiring a more severe treatment by liquid / liquid extraction. Thus atmospheric distillation allows, in one step, to obtain the different fractions desired (naphtha, diesel), thus facilitating hydrotreatment downstream adapted to each fraction and, therefore, direct fuel-based naphtha or diesel fuel products respecting the different specifications. Splitting after hydrotreatment is not necessary.
Thanks to the strong reduction of contaminants in the bed boiling, the light fractions (naphtha and diesel) contain less contaminants and can therefore be processed in a fixed-bed section generally having kinetics hydrogenation improved compared to the bubbling bed. Of same, the operating conditions can be softer thanks to limited contaminant content. Providing treatment for each fraction allows to have a better operability according to the products sought. Depending on the operating conditions chosen (more or less severe), one can obtain either a fraction to be sent to a fuel pool, a finished product respecting specifications (sulfur content, smoke point, cetane, content aromatic, etc.) in force.
Fixed bed hydrotreatment sections include preferably upstream of the hydrotreatment beds of the beds specific for arsenic and silicon compounds optionally contained in the naphtha and / or diesel fractions. The arsenic compounds escaping the bubbling bed (because generally relatively volatile) are fixed in the guard beds,

8 avoiding poisoning downstream catalysts, and allowing to obtain fuel bases heavily depleted of arsenic.
Atmospheric distillation also helps to concentrate the most refractory nitrogen compounds in the fraction more than the diesel fraction, thus limiting the amount to be treated by liquid / liquid extraction. The equipment, as well as the quantity of solvent required in the liquid / liquid extraction stage, are thus minimized.
The heavier fraction than the diesel fraction from the stage fractionation is subjected to a liquid / liquid extraction at using a polar solvent. The solvent used is a solvent for preferentially extracting aromatic compounds. As the remaining refractory nitrogen is usually found in aromatic compounds, the liquid / liquid extraction step allows to reduce nitrogen-containing aromatic compounds refractory to hydrodenitrogenation (denitrogenation by catalytic hydrogenation). he it is important to emphasize that the liquid / liquid extraction is done, unlike the state of the art, only on the heavy fraction, in order to avoid losses of fuel efficiency during the recovery of the solvent after extraction. The products we wants to extract the heavy fraction preferentially have a boiling point above the boiling point of the solvent for avoid a loss of efficiency when separating the solvent from the raffinate after extraction. Indeed, during the separation of the solvent of the raffinate, any compound having a boiling point below boiling point of the solvent will inevitably leave with the solvent and therefore lower the amount of raffinate obtained (and therefore the yield of fuel bases). For example, in the case of furfural as extraction solvent, having a boiling point of 162 C, compounds C10-, compounds representative of the fraction gasoline / naphta, will be lost. By treating only the fraction heavy material with compounds with boiling points higher than the boiling point of the extraction solvent, there is no loss of these compounds C10-. In addition, contamination is avoided solvent with the compounds C10- as well as the possible stages solvent treatment for recycling. Recovery solvent is therefore more efficient and economical.

9 Another advantage of the process is the fact that the raffinate from step e) of liquid / liquid extraction, after evaporation of the solvent, is preferably sent to a cracking section catalytic [step f)] in which it is treated under conditions to produce a gaseous fraction, a gasoline fraction, a diesel fraction and a residual heavy fraction called slurry according to the Anglo-Saxon terminology. This variant allows to maximize the performance of fuel bases.
Another interest is the fact that the extract from the extraction liquid / liquid may be at least partly recycled in step a) hydroconversion. Recycling allows for an increase in yield of fuel bases.
detailed description The hydrocarbon feedstock The hydrocarbon feedstock comprises at least one shale or a mixture of shale oils. The term oil of shale is used here in its broadest sense and is meant to include any shale oil or a fraction of shale oil, which contains nitrogen impurities. This includes shale oil whether obtained by pyrolysis, solvent extraction or by other means, shale oil that has been filtered to eliminate solids, or which has been treated by one or more solvents, chemicals, or other treatments and which contains nitrogen impurities. The term shale oil also includes the shale oil fractions obtained by distillation or by another fractionation technique.
The shale oils used in the present invention generally have a Conradson carbon content of less than 0.1% by weight and generally at least 5% by weight, asphaltenes content (standard 1P143 / C7) of at least 1%, often at least 2% by weight. Their sulfur content is generally at least 0.1%, often at least 1% and very often at least 2%, even up to 4% or even 7% by weight. The the amount of metals they contain is generally from minus 5 ppm by weight, often at least 50 ppm by weight, and typically at least 100 ppm by weight or at least 200 ppm by weight. Their nitrogen content is generally at least 0.5%, often at least 1% and very often at least 2% by weight.
Their arsenic content is generally greater than 1 ppm in weight, and up to 50 ppm by weight.
5 The method according to the present invention aims at converting shale oils. However, the charge can also contain, in addition to shale oil, other liquid hydrocarbons synthetic materials, especially those containing a significant amount of organic cyclic nitrogen compounds. This includes

10 of oils derived from coal, oils obtained from heavy tar, tar sands, pyrolysis oils wood residues such as wood residues, crudes from biomass (biocrudes), vegetable oils and fats animal.
Other hydrocarbon feedstocks can also complete the shale oil. The charges are chosen in the group formed by vacuum distillates and residues of distillation, vacuum distillates and converted from conversion processes such as, for example, those from distillation to coke (coking), products resulting from hydroconversion of heavy-duty fixed bed, products resulting from hydroconversion processes of heavy bed bubbling, and solvent-laden oils (for example deasphalted propane, butane and pentane oils which come from the deasphalting of residues under vacuum distillation direct or vacuum residues from processes hydroconversion). Charges may also contain LCO for light cycle oil in English various origins, heavy cutting oil (HCO for heavy cycle oil in English) of various origins, and also cuts diesel fuels from catalytic cracking generally distillation range from about 150 ° C. to about 650 ° C.
fillers may also contain aromatic extracts obtained as part of the manufacture of lubricating oils. The charges can also be prepared and used in a mixture, in all proportions.

11 Hydrocarbons added to shale oil or mixture of shale oils can represent from 20 to 60% by weight of the total hydrocarbon feed (shale oil or blend of oils added shale + hydrocarbons), or even 10% to 90% by weight.
hydroconversion According to the present invention, the load is firstly subjected to a hydroconversion step [step a)] bubbling bed.
Hydroconversion is understood to mean hydrogenation reactions, hydrotreatment, hydrodesulfurization, hydrodenitrogenation, hydrodemetallization and hydrocracking.
The operation of the bubbling bed catalytic reactor, including recycling the reactor liquids up to the through the agitated catalyst bed, is generally well known. The bubbling bed technologies use catalysts supported, usually in the form of extrusions whose diameter is generally of the order of 1 mm or less than 1 mm, for example greater than or equal to 0.7 mm. Catalysts remain within reactors and are not evacuated with the products. The activity catalytic can be kept constant by replacing (addition and withdrawal) in line of the catalyst. It is therefore not necessary to stop the unit to change the used catalyst, nor to increase reaction temperatures along the cycle for compensate for deactivation. In addition, working conditions constant operations allows to obtain efficiencies and consistent product qualities throughout the catalyst cycle.
Since the catalyst is kept agitated by recycling significant amount of liquid, the pressure drop on the reactor remains low and constant, and the heat of reaction is quickly averaged over the catalytic bed, which is almost isothermal and does not require cooling via the injection of quenches. The implementation of Hydroconversion in a bubbling bed makes it possible to get rid of catalyst contamination problems related to deposits impurities naturally present in shale oils.
The conditions of step a) of the charge treatment in presence of hydrogen are usually conventional conditions hydroconversion in bubbling bed of a hydrocarbon fraction

12 liquid. It is usually operated under a total pressure of 2 to 35 MPa, preferably from 10 to 20 MPa, at a temperature of 300 C to 550 C and often 400 C to 450 C. The hourly space velocity (VVH) and hydrogen partial pressure are factors important that we choose according to the characteristics of the product to be processed and the desired conversion. Most often, the VVH is in the range of 0.2 hr -1 to 1.5 hr -1 and 0.3 hours to 1 hour. The amount of hydrogen mixed with the load is usually 50 to 5000 normal cubic meters (Nm3) per cubic meter (m3) of liquid charge, and most often 100 to 1000 Nm3 / m3, and preferably 300 to 500 Nm3 / m3;
Most often, this step a) of hydroconversion can be implemented under the conditions of the TSTAR process, such as described for example in the article Heavy Oil Hydroprocessing, published by the Aiche, March 19-23, 1995, HOUSTON, Texas, paper number 42d. It can also be implemented under the conditions of the H-OIL process, as described for example in the article published by NPRA, Annual Meeting, March 16-18, 1997, JJ Colyar and LI
Wilson under the title THE H-OIL PROCESS, A WORLDWIDE LEADER
IN VACUUM RESIDUE HYDROPROCESSING.
The hydrogen needed for hydroconversion (and subsequent hydrotreatments) may be from steam reforming hydrocarbons (methane) or gas from shale bitumen during the production of shale oils.
The catalyst of step a) is preferably a catalyst conventional granular hydroconversion, comprising on a support amorphous at least one metal or metal compound having a hydro-dehydrogenating function. In general, we use a a catalyst whose porous distribution is adapted to the treatment of fillers containing metals.
The hydro-dehydrogenating function can be ensured by least one Group VIII metal selected from the group formed by the nickel and / or cobalt, optionally in combination with least one group VIB metal selected from the group consisting of molybdenum and / or tungsten. For example, one can use a catalyst comprising from 0.5 to 10% by weight of nickel and preferably from 1 to 5% by weight of nickel (expressed as nickel oxide

13 NiO) and from 1 to 30% by weight of molybdenum, preferably from 5 to 20% by weight of molybdenum (expressed as molybdenum oxide Mo03), on an amorphous mineral support. The total content of oxides Groups VIB and VIII are often 5 to 40% by weight and in general from 7 to 30% by weight and the weight ratio expressed as metal oxide between metal (or metals) of Group VI on metal (or metals) of group VIII is usually 20 to 1 and the most often 10 to 2.
The support of the catalyst will for example be chosen from group formed by alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals. This support can also contain other compounds, for example oxides selected from the group formed by the oxide of boron, zirconia, titanium oxide, phosphoric anhydride. We most often uses an alumina support, and very often a support of alumina doped with phosphorus and possibly boron. In this case, the concentration of phosphoric anhydride P205 is usually less than about 20% by weight and the most often less than about 10% by weight and at least 0.001% by weight weight. The concentration of boron trioxide B203 is usually from about 0 to about 10% by weight. The alumina used is usually y (gamma) or r (eta) alumina. This catalyst is most often in the form of extruded. Preferably, the catalyst of step a) is based on nickel and molybdenum, doped with phosphorus and supported on alumina. One can for example use a catalyst of the type HTS 458 marketed by the company AXENS.
Prior to the injection of the charge, the catalysts used in the process according to the present invention are preferably subjected to a sulfurization treatment allowing to transform, at least in part, the metallic species into sulphides before they come into contact with the load to be treated. This treatment sulphurization activation is well known to those skilled in the art and can be performed by any method already described in the literature either in-situ, that is to say in the reactor, or ex-situ.
The used catalyst is partly replaced by a catalyst fresh by racking down the reactor and introducing the top of the

14 fresh or new catalyst reactor at regular time interval, for example by spot addition, or almost continuously.
For example, fresh catalyst can be introduced every day.
The replacement rate of spent catalyst by fresh catalyst can be for example from about 0.05 kg to about 10 kg per m3 of charge. This withdrawal and replacement are carried out using devices allowing the continuous operation of this stage hydroconversion. The unit usually has a pump recirculation allowing the maintenance of the catalyst in bed bubbling by continuous recycling of at least a portion of the liquid withdrawn at the top of the reactor and reinjected at the bottom of the reactor. It is also possible to send the spent catalyst withdrawn from the reactor in a regeneration zone in which carbon is removed and the sulfur that it contains, then to send back this regenerated catalyst in step a) of hydroconversion.
The operating conditions coupled with the catalytic activity allow for conversion rates of the load that can from 50 to 95%, preferably from 70 to 95%. The rate of conversion mentioned above is defined as the fraction mass of the charge at the inlet of the reaction section minus the mass fraction of the heavy fraction having a boiling point more than 343 C at the exit of the reaction section, the whole divided by the mass fraction of the load at the entrance of the section reaction.
The technology of the bubbling bed makes it possible to treat heavily contaminated metal, sediment and heteroatoms without encountering pressure drop problems or clogging known in the case of use of fixed bed. Metals such as nickel, vanadium, iron and arsenic are largely removed from the charge by depositing on the catalysts during the reaction. The remaining arsenic (volatile) will be eliminated during hydrotreatment steps by specific guard beds. The sediments contained in shale oils are also removed by replacing the catalyst in the bubbling bed without disturbing the hydroconversion reactions. These steps also make it possible to eliminate by hydrodenitration the most much of the nitrogen, leaving only nitrogen compounds the most refractory.
The hydroconversion of step a) makes it possible to obtain an effluent containing not more than 3000 ppm, preferably not more than 2000 ppm 5 weight of nitrogen.
Fractionation by atmospheric distillation The effluent obtained at the hydroconversion stage is sent to least in part, and preferably in whole, in a zone of Fractionation from which is recovered by distillation a gaseous fraction, a naphtha fraction, a diesel fraction and a heavier fraction than the diesel fraction.
Preferably, the effluent obtained in step a) is fractionated by atmospheric distillation into a gaseous fraction having a point

Boiling point below 50 ° C., a naphtha fraction boiling between about 50 C and 150 C, a diesel fraction boiling between 150 C and 370 C, and a heavier fraction than the diesel fraction boiling generally above 340 C, preferably above above 370 C.
The naphtha and diesel fractions are then sent separately to hydrotreatment sections. The heavy fraction undergoes liquid / liquid extraction.
The gaseous fraction contains gases (H2, H2S, NH3, H2O, CO2, CO, C 1 -C 4 hydrocarbons, ...). It can advantageously undergo a purification treatment to recover hydrogen and recycle it in the hydroconversion section of step a) or in sections hydrotreating steps c) and d). C3- and C4 hydrocarbons may, after purification treatment, serve to constitute LPG products (liquefied petroleum gases). Incondensable gases (Ci C2) are generally used as internal fuel for heating furnaces for hydroconversion reactors and / or hydrotreating.
Hydrotreatment of the naphtha fraction and the fraction diesel The naphtha and diesel fractions are then submitted separately to fixed bed hydrotreatment [steps c) and d]. By

16 hydrotreatment is understood to mean hydrodesulfurization reactions, hydrodenitrogenation and hydrodemetallation. The objective is, according to operating conditions chosen in a more or less severe way, to bring the different cuts to the specifications (sulfur content, point of smoke, cetane, aromatic content, etc.) or to produce a synthetic crude oil. Treating the naphtha fraction in a hydrotreatment section and the diesel fraction in a other hydrotreatment section allows for better operability at the level of the operating conditions, in order to bring each cut to the required specifications with a maximum yield in one step per cut. So, the splitting after hydrotreatment is not necessary. The difference between the two hydrotreating sections is based more differences in operating conditions than on the choice of catalyst.
Fixed bed hydrotreatment sections include, preferably, upstream of the hydrotreatment catalytic beds, specific guard beds for arsenic (arsenic) compounds and silicon optionally contained in the naphtha and / or diesel. The arsenic compounds escaping the bubbling bed (because usually relatively volatile) are fixed in the beds of guard, thus avoiding poisoning downstream catalysts, and to obtain fuel bases that are heavily depleted in arsenic.
Guard beds to eliminate arsenic and silicon naphtha or diesel cuts are known to those skilled in the art. They include, for example, an absorbent mass comprising nickel deposited on a suitable support (silica, magnesia or alumina) as described in FR2617497, or a mass absorbent material comprising copper on a support, as described in FR2762004. We can also mention the guard beds marketed by AXENS: ACT 979, ACT989, ACT961, ACT981.
The operating conditions of each section hydrotreatment are adapted to the load to be treated. The operating conditions of hydrotreatment of the naphtha fraction are generally milder than those of the diesel fraction.

17 In the hydrotreating step of the naphtha fraction [step c)]
it is usually carried out under an absolute pressure of 4 to 15 MPa, often 10 to 13 MPa. The temperature during this step c) is usually from 280 C to 380 C, often from 300 C to 350 C. This temperature is usually adjusted according to the level desired hydrodesulfurization. Most often, space velocity hourly (VVH) is in a range of 0.1 h-1 to 5 h-1, and preferably from 0.5 h -1 to 1 h -1. The amount of hydrogen mixed with the charge is usually 100 to 5000 normal cubic meters (Nm3) per cubic meter (m3) of liquid charge, and most often 200 to 1000 Nm3 / m3, and preferably 300 to 500 Nm3 / m3. We operates effectively in the presence of hydrogen sulphide (for the sulphidation of the catalyst) and the partial pressure of hydrogen sulphide is usually 0.002 times to 0.1 times, and preferably from 0.005 times to 0.05 times the total pressure.
In the hydrotreating step of the diesel fraction [step d)]
it is usually carried out under an absolute pressure of 7 to 20 MPa, often 10 to 15 MPa. The temperature during this step c) is usually 320 C to 450 C, often 340 C to 400 C. This temperature is usually adjusted according to the level desired hydrodesulfurization. The hourly mass velocity ((t of load / h) / t of catalyst) is between 0.1 and 1 h-1. most often, the hourly space velocity (VVH) is within a range ranging from 0.2 h -1 to 1 h -1, and preferably from 0.3 h -1 to 0.8 h -1. The amount of hydrogen mixed with the load is usually 100 to 5000 normal cubic meters (Nm3) per cubic meter (m3) of load liquid, and most often from 200 to 1000 Nm3 / m3, and preferably from 300 to 500 Nm3 / m3. It operates usefully in the presence of hydrogen sulphide, and the partial pressure of hydrogen sulphide is usually 0.002 times to 0.1 times, and preferably 0.005 times at 0.05 times the total pressure.
In the hydrotreatment sections, the ideal catalyst should have a strong hydrogenating power, so as to carry out a refining deep products, and to achieve a significant lowering of sulfur and nitrogen content. In the preferred embodiment, the hydrotreatment sections operate at relatively low, which goes in the direction of a deep hydrogenation and a

18 coking limitation of the catalyst. We would not go beyond the present invention using, in sections hydrotreatment, simultaneously or in a manner successively, a single catalyst or several different catalysts.
Usually, the hydrotreatment of steps c) and d) is carried out industrially, in one or more current reactors descending liquid.
In both hydrotreatment sections [step c) and d)]
uses the same type of catalyst, the catalysts in each section may be the same or different. We use at least a fixed bed of conventional hydrotreatment catalyst, comprising on an amorphous support at least one metal or metal compound having a hydro-dehydrogenating function.
The hydro-dehydrogenating function can be ensured by least one Group VIII metal selected from the group formed by the nickel and / or cobalt, optionally in combination with least one group VIB metal selected from the group consisting of molybdenum and / or tungsten. For example, one can use a catalyst comprising from 0.5 to 10% by weight of nickel, and preferably from 1 to 5% by weight of nickel (expressed as nickel oxide NiO), and from 1 to 30% by weight of molybdenum, preferably from 5 to 20% by weight of molybdenum (expressed as molybdenum oxide M003), on an amorphous mineral support. The total oxide content of Group VI and VIII metals is often from about 5 to about 40%
by weight, and in general from about 7 to 30% by weight, and the ratio weight expressed as metal oxide between metal (or metals) group VIB on metal (or metals) of group VIII is in general from about 20 to about 1, and most often from about 10 to about 2.
The support is for example chosen from the group formed by alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals. This support can also contain other compounds and for example oxides selected from the group consisting of boron oxide, zirconia, oxide titanium, phosphoric anhydride. Most often we use a alumina support and very often a support of alumina doped with phosphorus and possibly boron. In this case

19 Phosphoric anhydride concentration P205 is usually less than about 20% by weight and most often less than about 10% by weight and at least 0.001% by weight. The B203 boron trioxide concentration is usually about 0 to about 10% by weight. The alumina used is usually a alumina y (gamma) or ri (eta). This catalyst is most often in the form of beads or extrudates.
Prior to the injection of the charge, the catalysts used in the process according to the present invention are preferably subjected to a sulfurization treatment allowing to transform, at least in part, the metallic species into sulphide before they come into contact with the load to be treated. This treatment sulphurization activation is well known to those skilled in the art and can be performed by any method already described in the literature either in-situ, that is to say in the reactor, or ex-situ.
The hydrotreatment of step c) of the naphtha cut allows to obtain a cut containing not more than 1 ppm by weight of nitrogen, preferably not more than 0.5 ppm of nitrogen and not more than 5 ppm by weight of sulfur, preferably at most 0.5 ppm of sulfur.
The hydrotreatment of step d) of the diesel cut allows to obtain a cut containing not more than 100 ppm of nitrogen, preferably not more than 20 ppm of nitrogen and not more than 50 ppm of sulfur, preferably at most 10 ppm of sulfur.
Liquid / liquid extraction The heavier fraction than the diesel fraction fractionation section by atmospheric distillation is then directed to a liquid / liquid type extraction step [step e)].
This step aims to extract the aromatic compounds, including the refractory nitrogen of the heavy fraction, to obtain a raffinate usable as a filler for catalytic cracking in a conventional fluid catalytic cracking unit. This thus allows to maximize the yield of fuel bases. So, the liquid / liquid extraction makes it possible to value a fraction classically too refractory for a hydrotreatment.
The extraction is done using a known solvent to extract preferentially aromatic compounds. As a solvent, can use furfural, N-methyl-2-pyrrolidone (NMP), sulfolane, dimethylformamide (DMF), dimethylsulfoxide (DMSO), phenol, or a mixture of these solvents in equal or different proportions.

The liquid / liquid extraction can be carried out by any means known to those skilled in the art. Extraction is generally performed in a mixer-settler or in an extraction column. Of preferably, the extraction is carried out in an extraction column.
The operating conditions are in general a ratio solvent! charge of 1/1 to 3/1, preferably 1/1 to 1.8 / 1, a temperature profile between room temperature and 150 C, preferably between 50 C and 150 C. The pressure is between atmospheric pressure and 2 MPa, preferably between the pressure atmospheric and 1 MPa.
15 The chosen solvent has a sufficiently high boiling point in order to fluidize the heavy fraction resulting from fractionation without vaporizing, the heavy fraction typically being conveyed to temperatures between 200 C and 300 C.
After contact of the solvent with the heavy fraction, two phases

20 form: (i) the extract, consisting of the parts of the heavy fraction not soluble in the solvent (and highly concentrated in aromatics containing refractory nitrogen), and (ii) the raffinate, consisting of solvent and soluble parts of the heavy fraction, which constitutes a catalytic cracking recoverable filler to increase the yield of fuel bases. The solvent is separated by distillation of the soluble parts and recycled internally to the process liquid / liquid extraction; solvent management being known from the skilled person.
Extraction makes it possible to obtain a raffinate containing at most 1500 ppm, preferably at most 1000 ppm nitrogen. At least one part, and preferably all of the raffinate from the extraction liquid / liquid, is preferably sent in a step of catalytic cracking.
According to a preferred variant, at least one part and preferably all of the extract obtained in step e) of extraction liquid / liquid is recycled at the entrance of step a).

21 According to another variant, the extract is sent to a section of oxyvapogazeification in which it is transformed into a gas containing hydrogen and carbon monoxide. This mixture gas may be used for the synthesis of methanol or for hydrocarbon synthesis by the Fischer-Tropsch reaction. This mixture, in the context of the present invention, is preferably sent in a steam conversion section (shift conversion into English) in which, in the presence of water vapor, it is converted to hydrogen and carbon dioxide. hydrogen obtained can be used in steps a), c) and d) of the process according to the invention. The extract obtained in step e) can also be used as a solid fuel or, after fluxing, as fuel liquid, or enter into the composition of bitumens and / or fuels heavy.
The liquid / liquid extraction of the heavy fraction thus allows to extract the refractory aromatic compounds containing nitrogen and contaminants (metals). Performing the extraction only on the heavy fraction avoids losses of charge for catalytic cracking and therefore to increase the overall efficiency of the process. Recycling the extract in step a) Hydroconversion also increases the yield.
Catalytic cracking Finally, according to a variant mentioned above in a catalytic cracking step [step fl], at least a portion, and of preferably all of the raffinate obtained in step e), can be sent, after evaporation of the solvent, in a section of catalytic cracking, in which it is treated so conventional in conditions well known to those skilled in the art, to produce a gaseous fraction, a gasoline fraction, a diesel fraction and a heavy fraction (called slurry according to Anglo-Saxon terminology). The diesel fraction will, for example, at least partly sent to fuel tanks and / or at least partially, if not all, recycled at step d) hydrotreating of diesel. The heavy fraction will, for example, at least partly, if not all, sent to the fuel pool heavy and / or recycled at least in part, or in whole, in step f)

22 catalytic cracking. In the context of the present invention, the term conventional catalytic cracking encompasses the processes of cracking comprising at least one regeneration step of partial combustion catalyst, and those comprising at least a step of catalyst regeneration by total combustion, and / or those comprising at least one combustion step partial and at least one step of total combustion.
For example, a brief description of the catalytic cracking (of which the first industrial implementation dates back to 1936 (HOUDRY process) or in 1942 for the use of fluidized bed catalyst) in ULLMANS ENCYCLOPEDIA OF
INDUSTRIAL CHEMISTRY VOLUME 18, 1991, pp. 61-64.
usually used a conventional catalyst including a matrix, optionally an additive and at least one zeolite. The amount of zeolite is variable but usually from about 3 to 60% by weight, often about 6 to 50% by weight and the most often from about 10 to 45% by weight. Zeolite is usually dispersed in the matrix. The amount of additive is usually from about 0 to about 30% by weight The amount of matrix represents the complement at 100% by weight. The additive is generally selected from the group consisting of metal oxides Group IIA of the Periodic Table of Elements, such as for example, magnesium oxide or calcium oxide, rare earth oxides and titanates of Group IIA metals. The matrix is most often a silica, an alumina, a silica alumina, a silica-magnesia, a clay or a mixture of many of these products. The most commonly used zeolite is zeolite Y. The cracking is carried out in a reactor substantially vertical, either in ascending mode or in descending. The choice of catalyst and operating conditions depend on the desired products according to the load treated, as for example described in the article of M.MARCILLY pages 990-991 published in the journal of the Institute French Oil Nov.-Dec. 1975 pages 969-1006. We operate usually at a temperature of 450 C to 600 C and times in the reactor less than 1 minute, often about 0.1 to about 50 seconds.

23 Step f) of catalytic cracking can also be a step of catalytic cracking in a fluidized bed, for example according to the process called R2R. This step can be executed in a conventional manner known to those skilled in the art under appropriate conditions of cracking to produce more hydrocarbon products low molecular weight. Descriptions of how and catalysts for use in fluidized bed cracking in this step f) are described for example in the documents of US-A-5286690, US-A-5324696 and EP-A-699224.
The fluidized catalytic cracking reactor can run up or down. Although this is not a preferred embodiment of the present invention, it is also conceivable to perform the cracking catalytic in a moving bed reactor. The catalysts of particularly preferred catalytic cracking are those which contain at least one zeolite, usually mixed with an appropriate matrix such as, for example, alumina, silica, silica-alumina.
FIG. 1 schematically represents the process according to present invention. Figure 2 schematically represents a variant of the process including the catalytic cracking step.
According to FIG. 1, the charge comprising shale oil (1) at to be treated between the line (21) in the hydroconversion section in bubbling bed (2), in the presence of hydrogen (3), hydrogen (3) being introduced by line (33). The effluent of the section boiling water hydroconversion (2) is sent via line (23) in an atmospheric distillation column (4), at the exit of which is recovered a gaseous fraction (30), a naphtha fraction (25), a gas oil fraction (27) and a heavier fraction than the diesel fraction (29). The gaseous fraction (30) containing the hydrogen can be purified (not shown) to recycle hydrogen and reinject it into the bed hydroconversion section bubbling (2) via line (33) and / or sections hydrotreatment (6) and / or (8) via lines (35) and (37). Fraction naphtha (25) is sent to a bed hydrotreatment section stationary (6) at the exit of which a naphtha fraction is recovered (13) depleted in impurities. The diesel fraction (27) is sent to

24 a hydrotreatment section in fixed bed (8) at the exit of which one recovering a diesel fraction (15) depleted of impurities. Both hydrotreatment sections (6) and (8) are fed by hydrogen via lines (35) and (37). The heavier fraction than the diesel fraction (29) is directed to an extraction step of type liquid / liquid (10) for extracting aromatics. This step extraction is done with a solvent (not shown) and produces a raffinate (17) and an extract (19). The extract (19), via the line (39), can be used as fuel or feed a unit of gasification to produce hydrogen and energy. he can also be recycled within the hydroconversion section (2) via the line (31).
In Figure 2, the steps (and reference signs) hydroconversion, separation and hydrotreatment are identical to Figure 1. The raffinate (17) leaving the stage liquid / liquid extraction can be directed into a section of catalytic cracking (12). The effluent from this section is managed via the line (43) to a fractionation section (14), preferably atmospheric distillation, from which one recovers a fuel fraction or middle distillate, comprising at least one petrol fraction (45), a diesel fraction (47) and a heavy fraction (51). The diesel fraction (47) is sent, at least in part, to fuel tanks and / or is recycled, at least in part, if not all, in step d) of hydrotreating diesel (8) via the line (49). The heavy fraction (slurry) (51) is, for example, at less, if not all, sent to the fuel pool heavy and / or is recycled, at least in part, or in whole, to the catalytic cracking step (12) via line (53).
Example We treat a shale oil whose characteristics are presented in Table 1.

Table 1: Characteristics of Shale Oil Charge Density 15/4 - 0.951 Hydrogen% by weight 10.9 Sulfur% by weight 1.9 Nitrogen% by weight 1.8 Oxygen% by weight 2.7 Asphaltenes% by weight 3,7 Conradson carbon% by weight 4,5 PPm metals 236 Shale oil is processed in a bed reactor bubbling water containing commercial catalyst HOC 458 from the 5 company Axens. The operating conditions for implementation are the following:
- Temperature in the reactor: 425 C
- Pressure: 195 bar (19.5 MPa) - Hydrogen / charge ratio: 400 Nm3 / m3 10 - overall VVH: 0.3 h-1 Liquid products from the reactor are fractionated by atmospheric distillation to a naphtha fraction (C5 + - 150 C), a gas oil fraction (150-370 C) and a residual fraction 370 Ct The naphtha fraction is subjected to a hydrotreatment in bed Fixed using a NiMo catalyst on alumina. Conditions The following are the following:
- Temperature in the reactor: 320 C
- Pressure: 50 bar (5 MPa) - Hydrogen / charge ratio: 400 Nm3 / m3 20 - overall VVH: 1 h-1 The diesel fraction is subjected to a hydrotreatment in a fixed bed using a NiMo catalyst on alumina. Conditions The following are the following:
- Temperature in the reactor: 350 C

25 - Pressure: 120 bar (12 MPa) - Hydrogen / charge ratio: 400Nm3 / m3 - overall VVH: 0.6 h-1 The residual fraction is extracted liquid / furfural liquid with a solvent / charge ratio of 1.8 / 1; at

26 a temperature of 100 C, and at atmospheric pressure. We obtain a raffinate and an extract.
The raffinate is then catalytically cracked using a catalyst containing 20% by weight of zeolite Y and 80%
by weight of a silica-alumina matrix. This charge preheated to 135 C is brought into contact at the bottom of a vertical reactor, with a regenerated hot catalyst from a regenerator. The catalyst inlet temperature in the reactor is 720 C.
The ratio of catalyst flow to charge flow is 6.0.
The heat input of the catalyst at 720 C allows the vaporization of the charge and the cracking reaction, which are endothermic. The average residence time of the catalyst in the reaction zone is about 3 seconds. The operating pressure is 1.8 bar absolute.
The catalyst temperature measured at the outlet of the reactor in bed fluidized driven ascending (riser) is 525 C. The hydrocarbons cracked and the catalyst are separated through cyclones located in a zone of disengagement (stripper) where the catalyst is stripped. The catalyst, which coked during the reaction then was stripped into the disengagement zone, then sent to the regenerator. The coke content of the solid (delta coke) at the regenerator inlet is 0.85%. This coke is burned by air injected into the regenerator. The combustion, very exothermic, raises the solid temperature from 525 C to 720 C.
regenerated and hot catalyst comes out of the regenerator and is returned in bottom of the reactor.
The hydrocarbons separated from the catalyst leave the zone of disengagement. They are directed to a fractionation tower main source from which gas and gasoline order of increasing boiling point, LCO, HCO and slurry sections (370 C +), at the bottom of the tower.
Table 2 gives the properties of the different loads of each stage as well as the yields obtained in the different units and overall yield. We then observe that starting from 100% by weight of shale oil, 87.2% by weight of products (LPG, naphtha, middle distillates) to specifications Euro V.

27 Table 2 Raffinat Extraction Bed Unit Total Extract seething Charge FCC
Properties Fraction Oil Raffinat Extract heavy shale bed boiling charge C point C5 + 360+ 360+ 360+
initial cut ( VS) Yield% in 100 15.0 8.1 6.9 on weight oil schist Density - 0.951 0.926 0.899 0.960 Sulfur% in 1.9 0.25 0.12 0.40 weight Total nitrogen% in 1.8 0.60 0.11 1.14 weight yield of each unit (C / O gas in 2.4 10.0 oil weight liquefied, LPG) Naphtha c / o in 23.0 55.0 weight Distillates c / o in 55.5 14.0 average weights Oil not% in 15.0 converted weight Yield% in on oil weight shale (C / O gas in 2,4 0,8 3,2 oil weight liquefied, LPG) Naphtha c / o in 23.0 4.4 27.4 weight Distillates c / o in 55,5 1,1 56,6 average weights Total bases c / o in 80.9 6.3 87.2 fuels weight liquids

Claims (15)

1. Process for the conversion of a shale oil or a mixture of shale oils with a nitrogen content of less than 0,1%, often at least 1% and very often at least 2% by weight, characterized in that it comprises the steps following:
a) The load is dealt with in one section hydroconversion in the presence of hydrogen, the said section comprising at least one bubbling bed reactor operating at upward flow of liquid and gas and containing at least one supported catalyst, (b) The effluent obtained in step (a) shall be sent to less in part, and often entirely in a zone of fractionation from which one recovers by atmospheric distillation a gaseous fraction, a naphtha fraction, a diesel fraction and a fraction heavy as the diesel fraction, (c) The said naphtha fraction is treated, at least part, and often entirely in one section of hydrotreatment, in the presence of hydrogen, said section comprising at least one fixed bed reactor containing at least minus a hydrotreatment catalyst, (d) The said diesel fraction is treated, at least part, and often entirely in another section of hydrotreatment, in the presence of hydrogen, said section comprising at least one fixed bed reactor containing at least minus a hydrotreatment catalyst, e) The heavier fraction than the diesel fraction is subjected to a liquid / liquid extraction in order to obtain a raffinate and an extract. The method of claim 1, wherein the effluent obtained in step a) is fractionated by distillation atmospheric into a gaseous fraction having a point boiling point below 50 ° C, a naphtha fraction boiling between about 50 ° C and 150 ° C, a boiling gas fraction between about 150 ° C and 370 ° C, and a heavier fraction than the diesel fuel type fraction boiling over 370 ° C. 3. Method according to one of the preceding claims, wherein the solvent of the liquid / liquid extraction step e) is selected from the group consisting of furfural, N-methyl-2-pyrrolidone, sulfolane, dimethylformamide, dimethylsulfoxide, phenol, or a mixture of these solvents in equal or different proportions. 4. Method according to one of the preceding claims, in which the e) liquid / liquid extraction step is performed with a solvent / charge ratio of 1/1 to 3/1, preferably 1/1 to 1.8 / 1, at a temperature between the temperature ambient temperature and 150 ° C, and at a pressure between atmospheric and 2 MPa, preferably between atmospheric and 1 MPa. 5. Method according to one of the preceding claims, in which the hydrotreatment sections in fixed bed stages c) and / or d) include upstream catalytic beds hydrotreatment of compounds-specific guard beds arsenic and silicon. 6. Method according to one of the preceding claims, wherein at least a portion of the raffinate obtained in step e) liquid / liquid extraction is sent after evaporation of solvent, in a catalytic cracking section, referred to step f), in which it is treated under conditions to produce a gaseous fraction, a fraction gasoline, a diesel fraction and a heavy fraction. The method of claim 6, wherein at least part of the heavy fraction obtained in step f) of catalytic cracking is recycled at the entrance of this step f). The process according to claim 6, wherein at least a portion of the diesel fraction obtained in step f) of Catalytic cracking is recycled in step d) hydrotreatment of diesel. 9. Method according to one of the preceding claims, wherein at least a portion of the extract obtained in step e) liquid / liquid extraction is recycled at the entrance of step a). 10. Method according to one of the preceding claims, wherein the hydroconversion step a) operates at a temperature between 300 ° C and 550 ° C, preferably between 400 ° C
and 450 ° C., at a total pressure of between 2 and 35 MPa, preferably between 10 and 20 MPa, at a mass speed hour ((t of load / h) / t of catalyst) between 0.2 and 1.5 h -1, preferably between 0.3 h -1 and 1 h -1, and at a ratio of hydrogen / charge between 50 and 5000 Nm3 / m3, preferably between 100 and 1000 Nm3 / m3. 11. Method according to one of the preceding claims, wherein step c) of hydrotreating the naphtha fraction operates at a temperature of between 280 ° C and 380 ° C, preferably between 300 ° C and 350 ° C, at a total pressure of between 4 and 15 MPa, preferably between 10 and 13 MPa, at a hourly mass velocity ((t of load / h) / t of catalyst) between 0.1 and 5 h -1, preferably between 0.5 h -1 and 1 h -1, and at a hydrogen / charge ratio of between 100 and 5000 Nm3 / m3, preferably between 200 and 1000 Nm3 / m3. 12. Method according to one of the preceding claims, wherein step d) hydrotreating the diesel fraction operates at a temperature between 320 ° C and 450 ° C, preferably between 340 ° C and 400 ° C, at a total pressure of between 7 and 20 MPa, preferably between 10 and 15 MPa, at a hourly mass velocity ((t of load / h) / t of catalyst) between 0.1 and 1 h -1, preferably between 0.3 h -1 and 0.8 h -1, and a hydrogen / charge ratio of between 100 and 5000 Nm3 / m3, preferably between 200 and 1000 Nm3 / m3. 13. Method according to one of the preceding claims, wherein the catalyst of hydroconversion step a) comprises a group VIII metal selected from the group formed by Ni and / or Co, optionally a chosen group VIB metal in the group formed by Mo and / or W, on an amorphous support selected from the group consisting of alumina, silica, silicas, aluminas, magnesia, clays and mixtures of minus two of these minerals. 14. Method according to one of the preceding claims, wherein the catalyst of steps c) and d) of hydrotreatment comprises a group VIII metal selected from the group formed by Ni and / or Co, optionally a chosen group VIB metal in the group formed by Mo and / or W, on an amorphous support selected from the group consisting of alumina, silica, silicas, aluminas, magnesia, clays and mixtures of at least two of these minerals. 15. Method according to one of the preceding claims, in which shale oil or the mixture of shale oils is completed by a hydrocarbon feed selected in the group formed by oils derived from coal, oils obtained from heavy tar and oil sands, vacuum distillates and direct distillation residues, vacuum distillates and unconverted process residues residue conversion, deasphalted oils to solvents, light cutting oils, heavy cutting oils, Diesel fuel cuts from catalytic cracking having in general a distillation range of about 150 ° C to about 650 ° C, aromatic extracts obtained in the context of the manufacture of lubricating oils, or mixtures thereof loads.