Hydrotreating process using an array of catalysts having a nickel and tungsten based catalyst on a silica-alumina support

Abstract

The present invention relates to a method for hydrotreating a hydrocarbon feedstock in which at least 50% by weight of the compounds have an initial boiling point above 300 °C and a final boiling point below 650 °C to obtain a hydrotreated effluent. The method includes the following steps: a) contacting the hydrocarbon feedstock with at least one first catalyst comprising an alumina support and an active phase consisting of nickel and molybdenum in the presence of hydrogen; b) contacting the effluent obtained in step a) with at least one second catalyst comprising a silica-alumina support, an active phase consisting of nickel and tungsten, and phosphorus and an organic compound in the presence of hydrogen.

Description

Technical Field

[0001] The present invention relates to a process for the hydrotreatment of hydrocarbon feedstocks using an arrangement of at least two specific catalysts. The aim of this process is the production of hydrodesulfurized, hydrodenitrified and / or hydrodearomatized feedstocks.

Background Art

[0002] Conventional hydrotreating catalysts generally comprise an oxide support and an active phase based on metals in the form of their oxides from groups VIb and VIII, and also contain phosphorus. The preparation of these catalysts generally involves the impregnation of the support with the metals and phosphorus, followed by drying and calcination steps, which make it possible to obtain the active phase in the form of their oxides. Prior to their use in the reactions of hydrotreatment and / or hydrocracking, these catalysts are generally subjected to sulfidation to form the active entities.

[0003] The improvement of their activity by the addition of organic compounds to hydrotreating catalysts has been recommended by those skilled in the art, particularly for catalysts prepared by impregnation and drying without subsequent calcination. These catalysts are often referred to as "additive-impregnated dried catalysts".

[0004] Normally, the aim of catalysts for the hydrotreatment of hydrocarbon fractions is to remove sulfur-based compounds, nitrogen-based compounds or aromatic compounds contained therein, for example, to bring petroleum products to the specifications (sulfur content, aromatic content, etc.) required for a given use (automotive fuel, gasoline or gas oil, domestic fuel oil, jet fuel).

[0005] Since air quality laws are becoming stricter in many countries, continuous efforts are being made to develop more effective catalysts and methods for the production of ultra-low sulfur fuels. Although significant progress has been made in the development of efficient catalysts for these methods, major challenges such as moderate saturation activity of aromatic hydrocarbons or hydrodenitrogenation remain.

[0006] Therefore, a reduction in the content of sulfur, nitrogen, and aromatic compounds is desirable in the field of pretreatment of hydrocracking processes or fluid catalytic cracking processes (or FCC (Fluid Catalytic Cracking) processes) to improve the performance quality in subsequent hydrocracking or FCC stages. These processes generally treat feedstocks highly saturated with sulfur, nitrogen, and aromatic compounds.

[0007] However, a hydrotreating catalyst optimized for hydrodesulfurization (HDS) is not automatically optimized for the saturation of aromatic compounds (or hydrodearomatization HDA) or hydrodenitrogenation (HDN), and vice versa. Therefore, it is often necessary to rely on an arrangement of catalysts where each catalyst is optimized for one type of hydrotreating.

[0008] Such an arrangement of supported catalysts is described, for example, in Patent Documents 1 to 5.

[0009] There are also arrangements of non-supported catalysts, also called "bulk" catalysts, which are known, for example, from Patent Documents 6 and 7. However, the arrangement of supported catalysts shows the advantage of using regenerable catalysts. Regenerable catalysts are less expensive (because they contain a lower loading of metal) and are active even at lower metal contents.

[0010] Patent Document 8 discloses a hydrotreating method using an arrangement of a supported molybdenum-based catalyst followed by a supported tungsten-based catalyst. This document does not disclose the distribution based on the volume of the two catalyst zones.

[0011] Patent Document 9 discloses a hydrotreating method using an arrangement of a supported CoMoP catalyst to which citric acid is added, followed by a supported NiMoWP catalyst. The volume of the first catalyst is 5% to 95%, and the volume of the second catalyst is 95% to 5%. Improvements in HDS and HDN are observed.

[0012] Regardless of the selected catalyst arrangement, it is not always possible to sufficiently enhance the performance quality of the catalyst system by the induced modification to meet the specifications regarding the sulfur, nitrogen, and / or aromatic compound content of the fuel. As a result, it has been raised that it is essential for refiners to find a new hydrotreating method with improved performance quality regarding activity and stability.

[0013] The company of the applicant of the present application has developed a method for hydrotreating a hydrocarbon feedstock, which includes contacting the specific arrangement of the catalyst that enables enhancing the overall activity and overall stability of this method with the said feedstock.

Prior Art Documents

Patent Documents

[0014]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Summary of the Invention

Means for Solving the Problems

[0015] (Summary) The present invention relates to a method for the hydrotreating of a hydrocarbon feedstock, wherein at least 50% by weight of the compounds of the feedstock have an initial boiling point above 300 °C and a final boiling point below 650 °C, the temperature during the hydrotreating is from 180 °C to 450 °C, the pressure is from 0.5 to 30 MPa, the space velocity is from 0.1 to 20 h -1 and the hydrogen / feedstock ratio, expressed as the volume of hydrogen measured under standard temperature and pressure conditions per volume of the liquid feedstock, is from 50 SL / L to 5000 SL / L, to obtain a hydrotreated effluent, the method comprising the following steps: a) A first hydrotreating step; carried out in a first hydrotreating reaction section using at least one catalyst bed containing at least one first hydrotreating catalyst; the hydrotreating reaction section is fed by a gas stream containing at least the hydrocarbon feedstock and hydrogen, the first catalyst comprising an alumina support and an active phase consisting of nickel and molybdenum, and optionally containing phosphorus and / or optionally an organic compound containing oxygen and / or nitrogen and / or sulfur; b) A second hydrotreating step; carried out in a second hydrotreating reaction section using at least one catalyst bed containing at least one second hydrotreating catalyst; the hydrotreating reaction section is fed by at least a part of the effluent obtained in step a), the second catalyst comprising a silica-alumina support, an active phase consisting of nickel and tungsten, phosphorus, and an organic compound containing oxygen and / or nitrogen and / or sulfur.

[0016] The company of the applicant has surprisingly found that the arrangement of a first hydrotreating reaction section containing a first catalyst based on an active phase composed of nickel and molybdenum on an alumina support and a second hydrotreating reaction section containing a second catalyst based on an active phase composed of nickel and tungsten on a more acidic support in the presence of phosphorus and an organic compound shows a synergistic effect in terms of activity and stability not only in hydrotreating, particularly in the hydrogenation of aromatic compounds (HDA), but also in hydrodenitrogenation (HDN) and / or hydrodesulfurization (HDS).

[0017] This enables the observation of the symbiosis of a first catalyst based on an active phase composed of nickel and molybdenum on a non-acidic or low-acidic support (alumina), which particularly performs a part of HDS and HDN, and a second catalyst based on an active phase composed of nickel and tungsten in the presence of phosphorus and an organic compound on a more acidic support (silica-alumina) by the correct choice of the active phase of each catalyst, the appropriate support, and the presence of phosphorus and / or an organic compound, enabling the modification of the structure of stubborn aromatic compounds (by isomerization and / or decomposition reactions), making these molecules more reactive, and thus promoting the HDA that was previously necessary to increase HDN particularly by tungsten, contributing to the increase in hydrogenation activity.

[0018] On the one hand, the second catalyst has been shown to be very active particularly in HDA and HDN, thereby making it possible to supplement the hydrotreating of the first catalyst necessary to achieve the specifications, particularly the reactions of HDS and HDN. Similarly, the stability is improved. This is because the cycle time is extended due to the reduction in the temperature required to carry out the reactions of HDS, HDN, and HDA.

[0019] On the other hand, the second catalyst does not deactivate as rapidly, thereby making it even more possible to increase the cycle time for standard feeds or to process feeds highly loaded with sulfur, nitrogen, and / or aromatic compounds.

[0020] The hydrotreating method according to the present invention is particularly suitable for a vacuum distillate feedstock. The hydrotreating method according to the present invention is also particularly suitable for the hydrotreating of feedstocks containing high contents of nitrogen and aromatic compounds, such as feedstocks resulting from catalytic cracking, coking or visbreaking.

[0021] By the method according to the present invention, it becomes possible to produce a hydrotreated hydrocarbon fraction, i.e., a fraction that does not simultaneously contain nitrogen-based compounds, sulfur-based compounds and most aromatic compounds. Preferably, according to the method of the present invention, the hydrodesulfurization (HDS) conversion is more than 95%, preferably more than 98%. Preferably, according to the method of the present invention, the hydrodenitrogenation (HDN) conversion is more than 90%, preferably more than 95%. Preferably, according to the method of the present invention, the hydrogenation of aromatic compounds (HDA) conversion is more than 35%, preferably more than 40%.

[0022] According to an alternative form, the first hydrotreating reaction section containing the first catalyst occupies a volume V1, the second hydrotreating reaction section containing the second catalyst occupies a volume V2, and the volume distribution V1 / V2 is 50% by volume / 50% by volume to 90% by volume / 10% by volume, respectively.

[0023] Due to the volume distribution of the two catalysts, in particular the fact that the second reaction section containing the second catalyst occupies a smaller volume than the first reaction section containing the first catalyst, while enhancing the activity and stability of the catalyst system compared to a system containing only one type of catalyst, it becomes possible to optimize the reactions of HDS, HDN and HDA carried out in the first or second reaction section to obtain a hydrocarbon fraction according to the specifications.

[0024] According to an alternative form, the volume distribution V1 / V2 is 70% by volume / 30% by volume to 80% by volume / 20% by volume for each of the first and second hydrotreating reaction sections.

[0025] According to an alternative form, the second catalyst is characterized by the following: - The nickel content, expressed in the form of NiO, is 1.2 wt% to 4.5 wt% based on the total weight of the catalyst. - The tungsten content, expressed in the form of WO3, is 16 wt% to 33 wt% based on the total weight of the catalyst. - The phosphorus content, expressed in the form of P2O5, is 1 wt% to 4 wt% based on the total weight of the catalyst.

[0026] According to an alternative form, the second catalyst is characterized by the following: - The nickel content, expressed in the form of NiO, is 1.3 wt% to 4.3 wt% based on the total weight of the catalyst. - The tungsten content, expressed in the form of WO3, is 17 wt% to 31 wt% based on the total weight of the catalyst. - The phosphorus content, expressed in the form of P2O5, is preferably 1.3 wt% to 3.4 wt% based on the total weight of the catalyst.

[0027] According to this alternative form, the second catalyst is further characterized by the following: - The molar ratio of Ni / W is 0.18 to 0.45 mol / mol. - The molar ratio of P / W is 0.18 to 0.45 mol / mol.

[0028] According to an alternative form, the silica content in the carrier of the second catalyst is 10 wt% to 50 wt% based on the total weight of the carrier.

[0029] According to an alternative form, the molybdenum content of the first catalyst, expressed as MoO3, is 5 wt% to 40 wt% based on the total weight of the catalyst, and the nickel content, expressed as NiO, is 1 wt% to 10 wt% based on the total weight of the catalyst.

[0030] According to an alternative form, the first catalyst further contains phosphorus, expressed as P2O5, at a content of 0.1 wt% to 20 wt% based on the total weight of the catalyst.

[0031] According to an alternative form, the first catalyst further contains an oxygen-containing and / or nitrogen-containing and / or sulfur-containing organic compound.

[0032] According to an alternative form, the organic compound is a compound containing one or more chemical functional groups selected from the functional groups of carboxyl, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea or amide, or alternatively a compound containing a furan ring or a sugar, preferably, it is γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, oxalic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, di(C1-C4 alkyl) succinate, more particularly dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known under the name furfural), 5-hydroxymethylfurfural, 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropionate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

[0033] According to an alternative form, the content rate of the organic compound is 1 wt% to 30 wt% based on the total weight of the catalyst.

[0034] According to an alternative form, the first and / or second catalyst is at least partially sulfided.

[0035] According to an alternative form, the hydrotreating method is carried out as a pretreatment in a fluidized bed catalytic cracking process.

[0036] According to an alternative form, the hydrotreating method is carried out as a pretreatment in a hydrocracking process.

Embodiments for Carrying Out the Invention

[0037] (Detailed Description of the Invention) (Definition) According to the present invention, the expressions "of between A and B" and "between A and B" are synonymous and mean that both limiting values (A, B) of the interval are included in the described range of values. In cases where this is not so and where the limiting values are not included in the described range, such facts will be made clear by the present invention.

[0038] Within the scope of the meaning of the present invention, various ranges of parameters for a given stage, for example, pressure ranges and temperature ranges, can be used alone or in combination. For example, within the scope of the meaning of the present invention, a range of suitable pressure values can be combined with a range of more suitable temperature values.

[0039] Subsequently, specific and / or preferred embodiments of the present invention are described. They can be used separately or in combination with each other, and there is no limitation on this combination if the combination is technically achievable.

[0040] According to the present invention, pressure is absolute pressure, also denoted as abs., and is given in MPa (absolute) (MPa absolute) (or absolute MPa (MPa abs.)) unless otherwise specified.

[0041] Subsequently, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, editor-in-chief D.R. Lide, 81st edition, 2000 - 2001). For example, Group VIII according to the CAS classification corresponds to the metals in columns 8, 9, and 10 according to the new IUPAC classification.

[0042] The term "specific surface area" means the BET specific surface area (S BET (m 2 / g)) determined by nitrogen adsorption in accordance with the standard ASTM D 3663 - 78 established from the Brunauer - Emmett - Teller method described in the journal "The Journal of the American Chemical Society", 1938, 60, 309.

[0043] The total pore volume of the catalyst or the support used in the preparation of the catalyst means the volume measured by mercury porosimetry in accordance with the standard ASTM D4284 - 83 at a maximum pressure of 4000 bar (400 MPa), using a surface tension of 484 dynes / cm and a contact angle of 140°. The wetting angle was assumed to be equal to 140° in accordance with the recommendations on pages 1050 - 1055 of the publication "Techniques de l'ingenieur, traite analyse et caracterisation" written by Jean Charpin and Bernard Rasneur. For better accuracy, the value of the total pore volume corresponds to the value of the total pore volume measured by mercury intrusion porosimetry on the sample minus the value of the total pore volume measured by mercury intrusion porosimetry on the same sample for a pressure corresponding to 30 psi (about 0.2 MPa).

[0044] The content of the metal from Group VIII and Group VIb is measured by X-ray fluorescence.

[0045] The content of the metal from Group VIb, the metal from Group VIII and phosphorus is expressed as the oxide after correction for the weight loss on ignition of the catalyst sample over 2 hours in a muffle furnace at 550 °C. The weight loss on ignition is due to the loss of volatile compounds. It is determined in accordance with ASTM D7348.

[0046] Hydroprocessing is understood to mean reactions that particularly include hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrogenation of aromatic compounds (HDA).

[0047] (Feedstock) The feedstock used in the hydrocracking process according to the present invention is a hydrocarbon feedstock, and the initial boiling point of at least 50% by weight of its compounds is above 300 °C and the final boiling point is below 650 °C, and preferably the initial boiling point of at least 60% by weight, suitably at least 75% by weight, more preferably at least 80% by weight of its compounds is above 300 °C and the final boiling point is below 650 °C. The boiling point T5 of the said feedstock is preferably above 300 °C, preferably above 340 °C, that is to say, the boiling point of 95% of the compounds present in the feedstock is above 300 °C, preferably above 340 °C.

[0048] A very wide variety of feedstocks can be processed by the hydrocracking process according to the present invention. The hydrocarbon feedstock is preferably HCO (Heavy Cycle Oil: heavy cycle oil: heavy gas oil produced from a catalytic cracking unit), vacuum distillate, for example obtained from direct distillation of crude oil, or gas oil obtained from a conversion unit, for example catalytic cracking, coking or visbreaking, aromatic compounds, a feedstock originating from a unit for extraction of a lubricating oil base, or a feedstock obtained from solvent dewaxing of a lubricating oil base, atmospheric residue and / or vacuum residue and / or a distillate originating from a process for desulfurization or hydroconversion of a fixed bed or fluidized bed of deasphalted oil, or the feedstock can be deasphalted oil, or can contain vegetable oil, or originates from the conversion of a feedstock produced from biomass. It can also be paraffin produced from the Fischer-Tropsch process. The hydrocarbon feedstock to be processed according to the hydrocracking process of the present invention can also be a mixture of the above-mentioned feedstocks. Preferably, the feedstock is a vacuum distillate.

[0049] The feedstock to be processed, particularly those mentioned above, generally contains heteroatoms such as sulfur, oxygen and nitrogen, and in the case of heavy feedstocks, they usually also contain metals.

[0050] The nitrogen content of the feedstock to be processed in the process according to the present invention is generally more than 500 ppm by weight, preferably 500 to 10,000 ppm by weight, more preferably 700 to 4000 ppm by weight, and even more preferably 1000 to 4000 ppm by weight.

[0051] The sulfur content of the feedstock to be processed in the process according to the present invention is generally 0.01% to 5% by weight, preferably 0.2% to 4% by weight, and even more preferably 0.5% to 3% by weight.

[0052] The hydrocarbon feedstock may, in some cases, contain metals, particularly nickel and vanadium. The total content of nickel and vanadium in the hydrocarbon feedstock is preferably less than 50 ppm by weight, preferably less than 25 ppm, more preferably less than 10 ppm.

[0053] The hydrocarbon feedstock may, in some cases, contain asphaltenes. The asphaltene content of the hydrocarbon feedstock is generally less than 3000 ppm, preferably less than 1000 ppm, and even more preferably less than 200 ppm.

[0054] The hydrocarbon feedstock may, in some cases, contain resins. The resin content can be more than 1% by weight, particularly more than 5% by weight. The resin content is measured according to the standard ASTM D 2007-11. The hydrocarbon feedstock can also contain a very small amount (less than 1% by weight) of resin.

[0055] The hydrocarbon feedstock can have any chemical nature, that is, it can have any distribution among different chemical families selected from paraffins, olefins, and naphthenes, except for the content of aromatic compounds described below.

[0056] The content of aromatic compounds in the feedstock is 20% by weight or more, preferably it is 25% to 90% by weight, more preferably 30% to 80% by weight. The content of aromatic compounds is determined according to the method described in the publication Burdett R.A, Taylor L.W and Jones L.C, Journal of Molecular Spectroscopy, Rept. Conf., Inst. Petroleum, London, 1954, 30-41 (Pub. 1955).

[0057] (Embodiments of Methods and Operating Conditions) The method according to the invention can be carried out in one, two or more reactors. It is generally carried out in a fixed bed.

[0058] When the method according to the invention is carried out in two reactors, step a) can be carried out in a first reactor containing a first reaction section traversed by the feedstock, and then step b) can be carried out in a second reactor containing a second reaction section and arranged downstream of the first reactor. Optionally, the effluent from step a) leaving the first reactor can be subjected to a separation step. This separation step makes it possible to separate a light fraction formed during the hydrogenation treatment in step a), in particular containing H2S and NH3, from a heavy fraction containing the partially hydrogenated hydrocarbons. The heavy fraction obtained after the separation step is subsequently introduced into the second reactor, which makes it possible to carry out step b) of the method according to the invention. The separation step can be carried out by distillation, flash separation or any other method known to those skilled in the art.

[0059] When the method is carried out in a single reactor, step a) is carried out in a first region containing a first reaction section, and step b) is carried out in a second region containing a second reaction section downstream of the first region.

[0060] The first hydrogenation reaction section containing the first catalyst occupies a volume V1, the second hydrogenation reaction section containing the second catalyst occupies a volume V2, and the volume distribution V1 / V2 is generally 50% by volume / 50% by volume to 90% by volume / 10% by volume, preferably 60% by volume / 40% by volume to 85% by volume / 15% by volume, particularly preferably 70% by volume / 30% by volume to 80% by volume / 20% by volume, in each of the first and second hydrogenation reaction sections.

[0061] Distribution according to the volumes of the two catalysts, in particular the fact that the second reaction section containing the second catalyst occupies a smaller volume than the first reaction section containing the first catalyst, makes it possible to optimize the HDS, HDN and HDA reactions taking place in the first or second reaction section. This is because a volume that is too large for the second catalyst does not allow for the quantitative decomposition of nitrogen-based compounds and, as a result, the HDA reaction is inhibited. Conversely, a volume that is too small for the second catalyst does not make it possible to maximize the HDA reaction.

[0062] The operating conditions used in step a) or b) of the hydrotreating process according to the invention are generally as follows: the temperature is preferably from 180 °C to 450 °C, preferably from 250 °C to 440 °C, the pressure is preferably from 0.5 to 30 MPa, preferably from 1 to 18 MPa, and the hourly space velocity is preferably from 0.1 to 20 h -1 , preferably from 0.2 to 5 h -1 -1. The hourly space velocity (HSV) is here defined as the ratio of the hourly flow rate by volume of the hydrocarbon feedstock to the volume of one or more catalysts. The hydrogen / feedstock ratio, expressed as the volume of hydrogen measured under standard temperature and pressure conditions per unit volume of liquid feedstock, is preferably from 50 L / L to 5000 L / L, preferably from 80 to 2000 L / L.

[0063] The operating conditions can be the same or different in steps a) and b). Preferably, they are the same.

[0064] (Composition of the catalysts used in the present invention) According to the invention, the present hydrotreating process uses an arrangement of a first catalyst and a second catalyst, the first catalyst comprising an alumina support and an active phase consisting of nickel and molybdenum, optionally containing phosphorus and / or an organic compound, and the second catalyst comprising a silica-alumina-based support, an active phase consisting of nickel and tungsten, phosphorus, and an organic compound.

[0065] (First catalyst) The first catalyst includes an alumina carrier and an active phase composed of nickel and molybdenum. It can further contain phosphorus and an organic compound, and in some cases, boron and / or fluorine.

[0066] The hydrogenation function of the first catalyst, also known as the active phase, is provided by nickel and molybdenum.

[0067] Preferably, the total content of nickel and molybdenum is advantageously expressed as an oxide and is more than 6% by weight based on the total weight of the catalyst.

[0068] Preferably, the content of molybdenum is expressed in the form of MoO3 and is 5% to 40% by weight, preferably 8% to 39% by weight, more preferably 10% to 38% by weight based on the total weight of the catalyst.

[0069] Preferably, the content of nickel is expressed in the form of NiO and is 1% to 10% by weight, preferably 1.5% to 9% by weight, more preferably 2% to 8% by weight based on the total weight of the catalyst.

[0070] Preferably, the molar ratio of nickel to molybdenum in the first catalyst is preferentially 0.1 to 0.8, preferably 0.15 to 0.6, and more preferably 0.2 to 0.5.

[0071] The first catalyst can also contain phosphorus as a dopant. The dopant is an additive element that does not exhibit any catalytic activity by itself but increases the catalytic activity of the active phase.

[0072] The content of phosphorus in the catalyst is expressed in the form of P2O5 and is 0.1% to 20% by weight, expressed as P2O5, preferably 0.2% to 15% by weight, and most preferably 0.3% to 11% by weight based on the total weight of the catalyst.

[0073] The molar ratio of phosphorus to molybdenum in the first catalyst is 0.05 or more, preferably 0.07 or more, preferably 0.08 to 1, preferably 0.1 to 0.9, and very preferably 0.15 to 0.8.

[0074] The first catalyst can advantageously also contain at least one dopant selected from boron, fluorine, and mixtures of boron and fluorine.

[0075] When the catalyst contains boron or fluorine, or a mixture of boron and fluorine, the content of boron or fluorine or a mixture of these two is preferably 0.1% by weight to 10% by weight, preferably 0.2% by weight to 7% by weight, and very preferably 0.2% by weight to 5% by weight, expressed as boric oxide and / or fluorine element, based on the total weight of the catalyst.

[0076] The pore volume of the catalyst is generally 0.1 cm 3 / g to 1.5 cm 3 / g, preferably 0.15 cm 3 / g to 1.1 cm 3 / g. The measurement of the total pore volume is carried out by mercury porosimetry according to standard ASTM D4284, with a contact angle of 140°, as described in the research book Adsorption by Powders & Porous Solids: Principle, Methodology and Applications, Academic Press, 1999 by Rouquerol F., Rouquerol J. and Singh K., for example, by a Micromeritics (registered trademark) brand Autopore III (registered trademark) model machine.

[0077] The first catalyst has a specific surface area of 5 to 400 m 2 / g, preferably 10 to 350 m 2 / g, preferably 40 to 350 m 2 / g, and very preferably 50 to 300 m 2It is characterized by the specific surface area per g. In the present invention, the specific surface area is determined by the BET method according to the standard ASTM D3663, and this method is described in the same research book cited above.

[0078] The carrier includes alumina, preferably extruded alumina. Preferably, the carrier consists of alumina, preferably gamma alumina.

[0079] The total pore volume of the alumina carrier is advantageously 0.1 to 1.5 cm 3 ·g -1 , preferably 0.4 to 1.1 cm 3 ·g -1 . The measurement of the total pore volume is carried out by mercury porosimetry according to the standard ASTM D4284, with a contact angle of 140°, as described in the research book Adsorption by Powders & Porous Solids: Principle, Methodology and Applications, Academic Press, 1999 by Rouquerol F., Rouquerol J. and Singh K., for example, by a Micromeritics (registered trademark) Autopore III (registered trademark) model machine.

[0080] The specific surface area of the alumina carrier is advantageously 5 to 400 m 2 ·g -1 , preferably 10 to 350 m 2 ·g -1 , more preferably 40 to 350 m 2 ·g -1 . In the present invention, the specific surface area is determined by the BET method according to the standard ASTM D3663, and this method is described in the same research book cited above.

[0081] The carrier is advantageously provided in the form of beads, extrudates, pellets or irregular non-spherical aggregates, and its specific shape can result from the crushing stage.

[0082] The first catalyst can further contain one or a group of organic compounds known for their role as additives. The function of the additives is to increase the catalytic activity as compared with non-additive catalysts. More specifically, the catalyst can further contain one or more oxygen-containing organic compounds and / or one or more nitrogen-containing organic compounds and / or one or more sulfur-containing organic compounds. Preferably, the catalyst can further contain one or more oxygen-containing organic compounds and / or one or more nitrogen-containing organic compounds. Preferably, the organic compound contains at least two carbon atoms as well as at least one oxygen and / or nitrogen atom and does not contain other heteroatoms.

[0083] Generally, the organic compound is a compound containing one or more chemical functional groups selected from functional groups such as carboxyl, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea or amide, or a compound containing a furan ring, or a compound selected from sugars.

[0084] The oxygen-containing organic compound can be one or more compounds selected from one or more chemical functional groups selected from carboxyl, alcohol, ether, aldehyde, ketone, ester or carbonate functional groups, or alternatively a compound containing a furan ring, or alternatively one or more selected from sugars. The oxygen-containing organic compound is understood here to mean a compound that does not contain another heteroatom. By way of example, the oxygen-containing organic compound is ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (molecular weight 200 - 1500 g / mol), propylene glycol, 2-butoxyethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-methoxyethoxy)ethanol, triethylene glycol dimethyl ether, glycerol, acetophenone, 2,4-pentanedione, pentanone, acetic acid, oxalic acid, maleic acid, malic acid, malonic acid, gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, succinic acid di(C1-C4 alkyl), more particularly dimethyl succinate, methyl acetoacetate, ethyl acetoacetate, 2-methoxyethyl 3-oxobutanoate, 2-methacryloyloxyethyl 3-oxobutanoate, dibenzofuran, crown ether, phthalic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-valerolactone, 2-acetylbutyrolactone, propylene carbonate, 2-furaldehyde (also known under the name furfural), 5-hydroxymethylfurfural (also known under the name 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, methyl 2-furoate, furfuryl alcohol (also known under the name furfuranol), furfuryl acetate, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, methyl 3-methoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,5-hexanediol, 3-ethyl-1,5-pentanediol, 2,4-diethyl-1,It can be one or more selected from the group consisting of 1,5-pentanediol, 5-methyl-2(3H)-furanone, butyl glycolate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate, dimethyl 3-oxoglutarate, dimethyl tartrate, diethyl tartrate, diisopropyl tartrate, di(tert-butyl) tartrate, dimethyl malate, diethyl malate, diisopropyl malate and dibutyl malate.,

[0085] The nitrogen-containing organic compound can be one or more selected from compounds containing one or more chemical functional groups selected from amine or nitrile functional groups. The nitrogen-containing organic compound is herein understood to mean a compound that does not contain another heteroatom. As an example, the nitrogen-containing organic compound can be one or more selected from the group consisting of ethylenediamine, diethylenetriamine, hexamethylenediamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, acetonitrile, octylamine, guanidine and carbazole.,

[0086] The oxygen- and nitrogen-containing organic compound(s) can be one or more selected from compounds containing one or more chemical functional groups selected from the functional groups of carboxyl, alcohol, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, amide, urea or oxime. The oxygen- and nitrogen-containing organic compound(s) is / are herein understood to mean a compound(s) not containing another heteroatom. As examples, the oxygen- and nitrogen-containing organic compound(s) can be one or more selected from the group consisting of 1,2-cyclohexanediaminetetraacetic acid, monoethanolamine (MEA), 1-methyl-2-pyrrolidinone, dimethylformamide, ethylenediaminetetraacetic acid (EDTA), alanine, glycine, nitrilotriacetic acid (NTA), N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTPA), tetramethylurea, glutamic acid, dimethylglyoxime, bicine, tricine, 2-methoxyethyl cyanoacetate, 1-ethyl-2-pyrrolidinone, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 1-methyl-2-piperidinone, 1-acetyl-2-azepanone, 1-vinyl-2-azepanone and 4-aminobutanoic acid.

[0087] The sulfur-containing organic compound(s) can be one or more selected from compounds containing one or more chemical functional groups selected from functional groups of thiol, thioether, sulfone or sulfoxide. As examples, the sulfur-containing organic compound(s) can be one or more selected from the group consisting of thioglycolic acid, 2,2'-thiodiethanol, 2-hydroxy-4-methylthiobutanoic acid, sulfone derivatives of benzothiophene or sulfoxide derivatives of benzothiophene, ethyl 2-mercaptopropionate, methyl 3-(methylthio)propionate and ethyl 3-(methylthio)propionate.

[0088] Preferably, the organic compound contains oxygen; preferably, it is γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, oxalic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, di(C1-C4 alkyl) succinate, more specifically dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known under the name of furfural), 5-hydroxymethylfurfural (also known under the name of 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

[0089] When it / they are present, the total content rate of one or more oxygen-containing and / or nitrogen-containing and / or sulfur-containing organic compounds present in the catalyst is generally 1 wt% to 30 wt%, preferably 1.5 wt% to 25 wt%, more preferably 2 wt% to 20 wt% based on the total weight of the catalyst.

[0090] During the preparation of the catalyst that requires a drying stage, one or more drying stages following the introduction of the organic compound are carried out at a temperature below 200 °C, and are calculated based on the carbon remaining on the catalyst to retain preferably at least 30%, preferably at least 50%, most preferably at least 70% of the amount of the introduced organic compound. The residual carbon is measured by elemental analysis according to ASTM D5373.

[0091] (Second catalyst) According to the present invention, the second catalyst comprises a silica-alumina support and an active phase composed of nickel and tungsten. The second catalyst according to the present invention also contains phosphorus and an organic compound as dopants. It can further contain boron and / or fluorine.

[0092] The hydrogenation functional body of the second catalyst, also known as the active phase, is composed of nickel and tungsten.

[0093] The second catalyst is characterized in the following aspects: - The nickel content, expressed in the form of NiO, is 1.2% to 4.5% by weight based on the total weight of the catalyst. - The tungsten content, expressed in the form of WO3, is 16% to 33% by weight based on the total weight of the catalyst. - The phosphorus content, expressed in the form of P2O5, is 1% to 4% by weight based on the total weight of the catalyst.

[0094] Preferably, the second catalyst is characterized in the following aspects: - The nickel content, expressed in the form of NiO, is 1.3% to 4.3% by weight, preferably 1.4% to 3.8% by weight, more preferably 1.5% to 3.4% by weight based on the total weight of the catalyst. - The tungsten content, expressed in the form of WO3, is 17% to 31% by weight, preferably 18% to 30% by weight, preferably 19% to 29% by weight, more preferably 20% to 26% by weight based on the total weight of the catalyst. - The phosphorus content, expressed in the form of P2O5, is preferably 1.3 wt% to 3.4 wt%, preferably 1.4 wt% to 3.1 wt%, and most preferably 1.5 wt% to 2.8 wt% based on the total weight of the catalyst.

[0095] Preferably, the Ni / W molar ratio is 0.18 to 0.45 mol / mol, preferably 0.20 to 0.43 mol / mol, and even more preferably 0.22 to 0.42 mol / mol.

[0096] Preferably, the P / W molar ratio is 0.18 to 0.45 mol / mol, preferably 0.20 to 0.43 mol / mol, and even more preferably 0.22 to 0.42 mol / mol.

[0097] Based on the active phase composed of nickel and tungsten in the presence of phosphorus and organic compounds deposited on the silica-alumina support, and showing specific ratios among the different metals and / or phosphorus as described above, the catalyst exhibits excellent hydrotreating activity and stability due to the synergistic effect, particularly in hydrodenitrogenation (HDN), hydrogenation of aromatic compounds (HDA), and also in hydrodesulfurization (HDS).

[0098] Without wishing to be bound by any one theory, the silica-alumina support of the second catalyst will likely be able to modify the most robust aromatic compound structures (by isomerization and / or decomposition reactions) and make these molecules more reactive. As a result, in combination with the silica-alumina support, by optimizing the content ratios of each metal (especially tungsten, which contributes benefits in terms of hydrogenation) and phosphorus using specific ratios, it becomes possible to increase the HDA that was previously necessary to increase HDN, leading to an overall improvement in the catalyst performance quality.

[0099] Therefore, the second catalyst having the above specific ratios is particularly suitable in the arrangement with the upstream first catalyst.

[0100] The second catalyst can also advantageously contain at least one dopant selected from boron, fluorine, and mixtures of boron and fluorine. When this dopant is present, its content is as described for the first catalyst.

[0101] The pore volume of the second catalyst is generally 0.1 cm 3 / g to 1.5 cm 3 / g, preferably 0.15 cm 3 / g to 1.1 cm 3 / g. The measurement of the total pore volume is carried out by mercury porosimetry according to standard ASTM D4284, with a contact angle of 140°, as described in the study by Rouquerol F., Rouquerol J., and Singh K., Adsorption by Powders & Porous Solids: Principle, Methodology and Applications, Academic Press, 1999, for example, by a Micromeritics® brand Autopore III® model machine.

[0102] The second catalyst has a specific surface area of 5 to 400 m 2 / g, preferably 10 to 350 m 2 / g, preferably 40 to 350 m 2 / g, most preferably 50 to 300 m 2 / g. In the present invention, the specific surface area is determined by the BET method according to standard ASTM D3663, and this method is described in the same study book cited above.

[0103] The carrier of the second catalyst preferably consists of silica - alumina.

[0104] The total pore volume of the silica - alumina carrier is advantageously 0.1 to 1.5 cm 3 ·g -1 , preferably 0.2 to 0.8 cm 3 ·g -1 , particularly preferably 0.3 to 0.6 cm 3 ·g-1 It is. The measurement of the total pore volume is carried out by mercury porosimetry according to the standard ASTM D4284, with a contact angle of 140°, as described in the research book Adsorption by Powders & Porous Solids: Principle, Methodology and Applications, Academic Press, 1999 by Rouquerol F., Rouquerol J. and Singh K., for example, by an Autopore III (registered trademark) model machine of the Micromeritics (registered trademark) brand.

[0105] The specific surface area of the silica-alumina carrier is preferably 5 - 400 m 2 ·g -1 , preferably 100 - 350 m 2 ·g -1 , more preferably 200 - 300 m 2 ·g -1 It is. In the present invention, the specific surface area is determined by the BET method according to the standard ASTM D3663, and this method is described in the same research book cited above.

[0106] The silica content in the carrier is at most 50% by weight based on the total weight of the carrier, generally 45% by weight or less, preferably 40% by weight or less. Preferably, the silica content in the carrier is 10% - 50% by weight, preferably 15% - 40% by weight, particularly preferably 20% - 35% by weight based on the total weight of the carrier.

[0107] The sources of silicon are well-known to those skilled in the art. By way of example, mention may be made of silicic acid, silica in powder or colloidal form (silica sol), or tetraethyl orthosilicate Si(OEt)4.

[0108] The silica-alumina support can advantageously further contain zeolite. In this case, any zeolite source known to those skilled in the art and any related preparation method can be incorporated. Preferably, the zeolite is selected from the group of FAU, BEA, ISV, IWR, IWW, MEI, UWY, and preferably, the zeolite is selected from the group of FAU and BEA, such as zeolite Y and / or beta zeolite, particularly preferably USY and / or beta zeolite, for example, there are USY and / or beta zeolite. When zeolite is present, its content is 0.1% to 50% by weight, preferably 0.1% to 10% by weight based on the total weight of the support.

[0109] The support is advantageously provided in the form of beads, extrudates, pellets or irregular non-spherical aggregates, and its specific shape can result from the crushing stage.

[0110] The second catalyst according to the present invention further contains one or a group of organic compounds, and the properties and amounts used thereof are described in the part regarding the first catalyst. When the two catalysts contain one or more organic compounds, the plurality of organic compounds can be the same or different.

[0111] Preferably, the organic compound of the second catalyst preferably contains oxygen; preferably, it is γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, oxalic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, di(C1-C4 alkyl) succinate, more particularly dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known under the name of furfural), 5-hydroxymethylfurfural (also known under the name of 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutyric acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

[0112] According to a preferred embodiment, the present hydrogenation treatment method uses an arrangement of a first hydrogenation treatment reaction section and a second hydrogenation treatment reaction section. The first hydrogenation treatment reaction section contains a first catalyst based on nickel and molybdenum on an alumina carrier in the presence of phosphorus and an organic compound. The second hydrogenation treatment reaction section contains a second catalyst based on nickel and tungsten on a silica-alumina carrier in the presence of phosphorus and an organic compound. The second catalyst is characterized by the following: - The nickel content, expressed in the form of NiO, is 1.3 wt% to 4.3 wt%, preferably 1.4 wt% to 3.8 wt%, more preferably 1.5 wt% to 3.4 wt% based on the total weight of the catalyst. - The tungsten content, expressed in the form of WO3, is 17 wt% to 31 wt%, preferably 18 wt% to 30 wt%, preferably 19 wt% to 29 wt%, more preferably 20 wt% to 26 wt% based on the total weight of the catalyst. - The phosphorus content, expressed in the form of P2O5, is preferably 1.3 wt% to 3.4 wt%, preferably 1.4 wt% to 3.1 wt%, most preferably 1.5 wt% to 2.8 wt% based on the total weight of the catalyst. - The Ni / W molar ratio is 0.18 to 0.45 mol / mol, preferably 0.20 to 0.43 mol / mol, even more preferably 0.22 to 0.42 mol / mol. - The P / W molar ratio is 0.18 to 0.45 mol / mol, preferably 0.20 to 0.43 mol / mol, even more preferably 0.22 to 0.42 mol / mol.

[0113] According to this preferred embodiment, the first hydrogenation reaction section containing the first catalyst occupies a volume V1, and the second hydrogenation reaction section containing the second catalyst occupies a volume V2. The volume distribution V1 / V2 is 50% by volume / 50% by volume to 90% by volume / 10% by volume, preferably 60% by volume / 40% by volume to 85% by volume / 15% by volume, and particularly preferably 70% by volume / 30% by volume to 80% by volume / 20% by volume, in each of the first and second hydrogenation reaction sections.

[0114] According to this embodiment, the organic compound is preferably selected from γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, di(C1-C4 alkyl) succinate, more particularly dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known under the name of furfural), 5-hydroxymethylfurfural (also known under the name of 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

[0115] (Preparation method) The first and second catalysts can be prepared by any method known to those skilled in the art for preparing supported catalysts.

[0116] The first and second catalysts can be prepared by a preparation method including the following steps: i) contacting a nickel precursor, a molybdenum precursor or a tungsten precursor, phosphorus if phosphorus is present, and an organic compound if an organic compound is present, with a support based on alumina or silica-alumina to obtain a catalyst precursor; ii) drying the catalyst precursor resulting from step i) at a temperature below 200 °C; iii) optionally, calcining the catalyst precursor obtained in step ii) at a temperature of 200 °C to 550 °C; iv) optionally, sulfiding the catalyst obtained in step ii) or step iii).

[0117] During the contacting operation of step i), the preparation of the first and second catalysts can be carried out by impregnating the selected support with metals and phosphorus. The impregnation can be carried out, for example, by a method known to those skilled in the art under the term dry impregnation. In dry impregnation, just the right amount of the desired elements in the form of soluble salts is introduced into a selected solvent, such as demineralized water, so as to fill the porous part of the support as accurately as possible.

[0118] The precursors of the active phase can be introduced simultaneously or continuously. The impregnation of each precursor can advantageously be carried out at least twice. Different precursors can thus advantageously be impregnated continuously with different numbers of impregnation and aging times. One of the precursors can also be impregnated several times.

[0119] Preferably, the precursors of the active phase are introduced simultaneously.

[0120] Nickel precursors that can be used are preferably selected from nickel oxides, hydroxides, hydroxycarbonates, carbonates and nitrates; for example, nickel hydroxycarbonate, nickel carbonate or nickel hydroxide are preferably used.

[0121] Molybdenum precursors that can be used are well known to those skilled in the art. For example, among the sources of molybdenum that may be used are oxides and hydroxides, molybdic acid and its salts, especially ammonium salts, such as ammonium molybdate or ammonium heptamolybdate, phosphomolybdic acid (H3PMo 12 O 40 ) and its salts, and optionally silicomolybdic acid (H4SiMo 12 O 40 ) and its salts. The source of molybdenum can also be a heteropoly compound, such as a heteropoly compound of the Keggin, defective Keggin, substituted Keggin, Dawson, Anderson or Strandberg type. Preferably used are molybdenum trioxide and heteropolyanions of the Strandberg, Keggin, defective Keggin or substituted Keggin type.

[0122] Tungsten precursors that can be used are also well known to those skilled in the art. For example, among the sources of tungsten that may be used are oxides and hydroxides, tungstic acid and its salts, especially ammonium salts, such as ammonium tungstate or ammonium metatungstate, phosphotungstic acid and its salts, and optionally silicotungstic acid (H4SiW 12 O 40 ) and its salts. The source of tungsten can also be a heteropoly compound, such as of the Keggin, defective Keggin, substituted Keggin or Dawson type. Preferably used are oxides and ammonium salts, such as ammonium metatungstate, or heteropolyanions of the Keggin, defective Keggin or substituted Keggin type.

[0123] Phosphorus can be introduced completely or partially by impregnation. Preferably, it is introduced by impregnation, preferably dry impregnation, using a solution containing precursors of nickel, molybdenum and tungsten.

[0124] Said phosphorus can advantageously be introduced alone or as a mixture with the active phase, which can be done during any of the stages of impregnation of the hydrogenating function if the hydrogenating function is introduced a number of times. Said phosphorus can also be introduced, in whole or in part, during the impregnation thereof if oxygen-containing and / or nitrogen-containing and / or sulfur-containing organic compounds are introduced separately from the hydrogenating function (in the cases of post-impregnation and pre-impregnation described later). It can also be introduced at any stage of the synthesis of the support, from the synthesis of the support. It can, therefore, be introduced, for example, preferably before, during or after the kneading of a selected alumina gel matrix which is an alumina precursor, for example boehmite.

[0125] A suitable phosphorus precursor is orthophosphoric acid H3PO4, but its salts and esters, for example ammonium phosphate, are also suitable. Phosphorus can also be introduced simultaneously with one or more elements from Group VIb in the form of a Keggin, defective Keggin, substituted Keggin or Strandberg type heteropolyanion.

[0126] Any impregnation solution described in the present invention may contain any polar solvent known to those skilled in the art. The polar solvent used is preferably selected from the group formed by methanol, ethanol, water, phenol and cyclohexanol, and these are used alone or as a mixture. Preferably, a polar protic solvent is used. A list of common polar solvents and their dielectric constants can be found in the book "Solvents and Solvent Effects in Organic Chemistry", C. Reichardt, Wiley-VCH, 3rd edition, 2003, pages 472-474. Most preferably, the solvent used is water or ethanol, and particularly preferably, the solvent is water. In one possible embodiment, the solvent may not be present in the impregnation solution.

[0127] When the first or second catalyst further contains a dopant selected from boron, fluorine or a mixture of boron and fluorine, the introduction of this (these) dopant(s) can be carried out in various ways at various stages of the preparation, similar to the introduction of phosphorus described above.

[0128] The boron precursor can be boric acid, orthoboric acid H3BO3, ammonium diborate or ammonium pentaborate, boron oxide or a borate ester. Boron can be introduced, for example, by a solution of boric acid in a water / alcohol mixture or in a water / ethanolamine mixture. Preferably, the boron precursor is orthoboric acid if boron is to be introduced.

[0129] Fluorine precursors that can be used are well known to those skilled in the art. For example, fluoride anions can be introduced in the form of hydrofluoric acid or its salts. These salts are formed by alkali metals, ammonium or organic compounds. In the case of organic compounds, the salts are preferably formed in the reaction mixture by reaction between the organic compound and hydrofluoric acid. Fluorine can be introduced, for example, by impregnation with an aqueous solution of hydrofluoric acid or ammonium fluoride or ammonium bifluoride.

[0130] The second catalyst, or the oxygen-containing and / or nitrogen-containing and / or sulfur-containing organic compounds of the first catalyst when the first catalyst is present, are introduced before drying step ii). The organic compounds are generally introduced by impregnation, in the presence or absence of the active phase and phosphorus and in the presence or absence of a solvent.

[0131] The introduction of the organic compounds includes several embodiments that are particularly different in terms of the timing of the introduction of the organic compounds relative to the introduction of the metal. It can be carried out simultaneously with (co-impregnation) or after (post-impregnation) or finally before (pre-impregnation) the impregnation of the metal, particularly during the preparation of the support, preferably during shaping or by impregnation on a pre-formed support. Each embodiment can be used alone or in combination and can be carried out in one or more steps.

[0132] Furthermore, the contacting step can combine at least two embodiments, for example co-impregnation and post-impregnation. According to an alternative embodiment, the contacting operation according to step i) combines at least two contacting embodiments, for example co-impregnation with the organic compounds of the active phase and phosphorus, then drying at a temperature below 200°C, and then post-impregnation with an organic compound that can be the same or different from that used for the co-impregnation. Each embodiment can be used alone or in combination and can be carried out in one or more steps.

[0133] When the second catalyst and the first catalyst are present, the organic compound of the first catalyst is preferably introduced by post-impregnation. In this case, the metal and phosphorus are first introduced, drying is carried out at a temperature below 200 °C, the organic compound is introduced, and then drying is carried out at a temperature below 200 °C, but no subsequent calcination is carried out.

[0134] One or more organic compounds are preferably introduced into the impregnation solution, and the impregnation solution can be the same solution or a different solution containing the precursors of the active phase and phosphorus depending on the implementation form of the preparation, and the amounts are as follows: - The total molar ratio of the organic compound pair to one or more elements from Group VIb of the catalyst precursor (Mo for the first catalyst or W for the second catalyst) is calculated based on the components introduced into one or more impregnation solutions and is 0.01 to 5 mol / mol, preferably 0.05 to 3 mol / mol, preferably 0.05 to 1.5 mol / mol, and most preferably 0.1 to 1.2 mol / mol, and - The molar ratio of the organic compound pair to nickel is calculated based on the components introduced into one or more impregnation solutions and is 0.02 to 17 mol / mol, preferably 0.1 to 10 mol / mol, preferably 0.15 to 8 mol / mol, and most preferably 0.6 to 5 mol / mol.

[0135] When several organic compounds are present, different molar ratios apply to each of the organic compounds present.

[0136] Advantageously, after each impregnation stage, the impregnated support is aged by standing. Aging enables the impregnation solution to be uniformly dispersed within the support.

[0137] Any aging stage described in the present invention is preferably carried out at atmospheric pressure, in a water-saturated atmosphere, at a temperature of 17 °C to 50 °C, preferably at ambient temperature. Generally, an aging period of 10 minutes to 48 hours, preferably 30 minutes to 5 hours is sufficient. Longer periods are not excluded but do not necessarily provide any improvement.

[0138] According to step ii) of the preparation method according to the present invention, the catalyst precursor obtained in step i) and optionally aged is subjected to a drying step, and the temperature at that time is less than 200°C, preferably 50°C to 180°C, preferably 70°C to 150°C, and very preferably 75°C to 130°C.

[0139] The drying step is advantageously carried out by any technique known to those skilled in the art. It is advantageously carried out at atmospheric pressure or reduced pressure, preferably at atmospheric pressure. It is advantageously carried out in a traversed bed using hot air or any other hot gas. Preferably, when drying is carried out in a fixed bed, the gas used is either air or an inert gas, such as argon or nitrogen. Very preferably, drying is carried out in a traversed bed in the presence of nitrogen and / or air. Preferably, the drying step has a short duration of 5 minutes to 4 hours, preferably 30 minutes to 4 hours, and very preferably 1 hour to 3 hours. When an organic compound is present, drying is carried out so as to preferentially retain at least 30% of the introduced organic compound; preferably, this amount is calculated based on the carbon remaining on the catalyst and is more than 50%, and even more preferably more than 70%. At the end of the drying step b), a dried catalyst is obtained.

[0140] Optionally, after the drying step ii), a calcination step iii) can be carried out.

[0141] According to this alternative form, at the end of the drying stage ii), the calcination stage c) is carried out at a temperature of 200 °C to 600 °C, preferably 250 °C to 550 °C, under an inert atmosphere (e.g., nitrogen) or under an atmosphere containing oxygen (e.g., air). The duration of this heat treatment is generally 0.5 hour to 16 hours, preferably 1 hour to 5 hours. After this treatment, the active phase is, therefore, found in the form of an oxide; the heteropolyanion is, therefore, converted to an oxide. Similarly, the catalyst no longer contains, or hardly contains, the organic compound when the organic compound is introduced. However, the introduction of the organic compound during its preparation makes it possible to increase the dispersion of the active phase and, therefore, results in a more active catalyst.

[0142] When an organic compound is present, the catalyst is preferably not subjected to calcination. The term "calcination" is understood here to mean a heat treatment at a temperature of 200 °C or higher under a gas containing air or oxygen.

[0143] However, the catalyst precursor can undergo a calcination stage, especially after impregnation of the active phase and phosphorus, before the introduction of the organic compound.

[0144] The first or second catalyst can be a fresh catalyst, i.e., a catalyst unit that has not been used as a catalyst until then, especially in a hydrogenation treatment.

[0145] The first or second catalyst according to the present invention can also be a catalyst for regeneration and / or rejuvenation. A catalyst for regeneration and / or rejuvenation is understood to mean a catalyst which is used as a catalyst in a catalyst unit, in particular in hydrotreatment and / or hydrocracking, and which has been subjected to at least one step of partial or complete removal of coke, for example by calcination (regeneration). Regeneration can be carried out by any means known to those skilled in the art. Regeneration is generally carried out by calcination at a temperature of from 350°C to 550°C, generally from 400°C to 520°C, or from 420°C to 520°C, or from 450°C to 520°C, and a temperature below 500°C is often advantageous.

[0146] If the regenerated catalyst no longer contains a sufficient active phase and / or phosphorus, or if it exhibits one or more ratios outside the above-mentioned preferred ratios, the regenerated catalyst can be rejuvenated by introducing one or more precursors of the active phase and / or phosphorus into the regenerated catalyst. It is also possible to introduce at least one organic compound simultaneously with or separately from the metal and phosphorus. The organic compound introduced may or may not be the same as the organic compound of this catalyst if the fresh catalyst contained such an organic compound. The above operating conditions regarding aging, drying and optionally calcination and optionally sulfidation are of course applicable in the context of this last embodiment.

[0147] Before its use in the hydrotreatment reaction, it is advantageous to convert the first and / or second catalyst into a sulfided catalyst so as to form its active form. This activation or sulfidation step is carried out by a method well known to those skilled in the art, preferably under a sulfidizing reducing atmosphere in the presence of hydrogen and hydrogen sulfide.

[0148] According to an alternative form, the first or second catalyst is preferably subjected to a sulfidation step after the drying step ii) or the optional calcination step iii).

[0149] The catalyst is preferably sulfided ex situ or in situ. The sulfiding agent is H2S gas, elemental sulfur, CS2, thiols, sulfides and / or polysulfides, a hydrocarbon fraction containing sulfur compounds and having a boiling point of less than 400 °C, or any other sulfur-containing compound used for the activation of hydrocarbon feedstocks for the purpose of sulfiding the catalyst. The sulfur-containing compound is preferably selected from alkyldisulfides such as dimethyl disulfide (DMDS), alkyl sulfides such as dimethyl sulfide, thiols such as n-butyl thiol (or 1-butanethiol), and polysulfide compounds of the tert-nonyl polysulfide type. The catalyst can also be sulfided by sulfur contained in the feedstock to be desulfurized. Preferably, the catalyst is sulfided in situ in the presence of a sulfiding agent and a hydrocarbon feedstock. Most preferably, the catalyst is sulfided in situ in the presence of a hydrocarbon feedstock to which dimethyl disulfide has been added.

[0150] (Application of the method according to the invention in a hydrocracking process) According to a first alternative form, the hydrotreating method according to the invention is preferably carried out as a pretreatment in a hydrocracking process, more particularly in a "single-stage" or "two-stage" hydrocracking process. By means of the hydrocracking process, it is possible to convert petroleum fractions, in particular vacuum distillates (VDs), into lighter and more upgradable products (gasoline, middle distillates). The hydrotreating method according to the invention is aimed at removing sulfur-based compounds, nitrogen-based compounds or aromatic compounds present in the vacuum distillate fraction.

[0151] The "single-stage" hydrocracking process generally first involves a thorough hydrogenation treatment, the purpose of which is to perform thorough HDN, thorough HDS, and thorough HDA of the feedstock before the feedstock is sent onto one or more hydrocracking catalysts. The single-stage hydrocracking process is particularly advantageous when the one or more hydrocracking catalysts comprise a support containing zeolite crystals. This thorough hydrogenation treatment of the feedstock only results in a limited conversion of the feedstock into lighter fractions, which is still insufficient and therefore needs to be completed on one or more more active hydrocracking catalysts. However, it should be noted that no separation of the effluent occurs between different catalyst beds: all of the effluent at the outlet of the hydrogenation treatment catalyst bed is injected onto one or more catalyst beds containing the one or more hydrocracking catalysts, and then the formed products are separated. This version of hydrocracking has an alternative form, which shows the recycling of the unconverted fraction to at least one of the hydrocracking catalyst beds for the purpose of a more thorough conversion of the feedstock. Advantageously, the hydrogenation treatment process according to the invention, which comprises a specific sequence according to the invention, is carried out upstream of the hydrocracking catalyst in the single-stage hydrocracking process. In addition, this makes it possible to limit the nitrogen content at the end of the pretreatment stage and protect the zeolite-based hydrocracking catalysts, which are very sensitive to nitrogen.

[0152] The "two-stage" hydrocracking process includes a first stage, the purpose of which is, as in the "single-stage" process, to carry out the hydrogenation treatment of the feedstock, but generally also to achieve a conversion of the feedstock of about 40% - 60%. The effluent resulting from the first stage is subsequently subjected to separation (generally by distillation), which is most often referred to as an intermediate separation, the purpose of which is to separate the conversion products from the unconverted fraction. In the second stage of the two-stage hydrocracking process according to the present invention, only the fraction of the feedstock that was not converted during the first stage is processed. This separation enables the two-stage hydrocracking process according to the present invention to be more selective with respect to the intermediate distillate (kerosene + diesel) than the single-stage process according to the present invention. This is because the intermediate separation of the conversion products prevents them from being "over-cracked" to give naphtha and gas on one or more hydrocracking catalysts in the second stage. Furthermore, it should be noted that the unconverted fraction of the feedstock processed in the second stage generally contains NH3 and also nitrogen-based organic compounds at a very low content: generally less than 20 weight ppm, and actually less than 10 weight ppm.

[0153] The first stage is carried out in the presence of a specific arrangement of the catalysts according to the present invention and a hydrocracking catalyst, such that the hydrogenation treatment and conversion are generally carried out on the order of 40% - 60%. The catalyst bed of the specific arrangement of the catalysts according to the present invention is preferably found upstream of the hydrocracking catalyst. The second stage is generally carried out in the presence of a hydrocracking catalyst that is compositionally different from that present for the implementation of the first stage.

[0154] The hydrocracking process is generally carried out at a temperature of 250°C - 480°C, preferably 320°C - 450°C, more preferably 330°C - 435°C, under a pressure of 2 - 25 MPa, preferably 3 - 20 MPa. The hourly space velocity (HSV) of the feedstock with respect to the volume of each catalyst is preferably 0.1 - 40 h -1 , preferably 0.2 - 12 h -1 , most preferably 0.4 - 6 h -1 and the hydrogen / feedstock ratio is the standard cubic meter of hydrogen (Sm 3) / cubic meters of hydrocarbon feedstock (m 3 ) is represented as, preferably 80 SL / L to 5000 SL / L, more preferably 100 to 2000 SL / L. The methods for hydrocracking the vacuum distillate cover a range of pressures and conversions extending from mild hydrocracking to high-pressure hydrocracking. Mild hydrocracking is understood to mean hydrocracking that results in a moderate conversion rate: generally less than 40%, and operates at low pressure, preferably 2 MPa to 6 MPa.

[0155] The hydrocracking catalysts are of the bifunctional type: they combine an acid function with a hydrogenation / dehydrogenation function. The acid function is provided by a porous support, the surface of which is generally 150 m 2 ·g -1 to 800 m 2 ·g -1vary up to and indicate a surface acidity, and include, for example, halogenated (especially chlorinated or fluorinated) aluminas, combinations of boron and aluminum oxides, amorphous or crystalline mesoporous aluminosilicates, and zeolites dispersed in an oxide binder. The hydrogenation / dehydrogenation function is provided by the presence of an active phase based on at least one metal from Group VIb of the Periodic Table of the Elements and optionally at least one metal from Group VIII. The most common formulations are of the nickel-molybdenum (NiMo) and nickel-tungsten (NiW) types, and more rarely of the cobalt-molybdenum (CoMo) type. After preparation, the hydrogenation / dehydrogenation function bodies often exist in oxide form. The usual method for forming the hydrogenation / dehydrogenation phase of a hydrocracking catalyst consists of the deposition of one or more molecular precursors of at least one metal from Group VIb and optionally at least one metal from Group VIII on an acidic oxide support, followed by the steps of "dry impregnation", subsequent aging, drying, and calcination, which result in the formation of the oxidized form of one or more of the metals used. Since the active and stable form for the hydrocracking process is the sulfided form, these catalysts need to undergo a sulfiding step. This sulfiding step can be carried out in the unit of the relevant process (reference is made to in-situ sulfiding) or prior to the filling of the unit with the catalyst (here reference is made to ex-situ sulfiding).

[0156] (Application of the method according to the invention in the FCC process) According to a second alternative form, the hydrotreating process according to the invention is advantageously carried out as a pretreatment in the fluid catalytic cracking (or FCC: fluid catalytic cracking) process. The FCC process is a conventional method known to those skilled in the art and can be carried out for the purpose of producing hydrocarbon products of lower molecular weight under suitable cracking conditions. For example, a general description of catalytic cracking (the first industrial use of catalytic cracking dates back to 1936 (Houdry process) or the use of fluidized bed catalysts dates back to 1942) will be found in Ullmann’s Encyclopedia of Industrial Chemistry, Volume A 18, 1991, pages 61 to 64.

[0157] Conventionally used in the FCC process are catalysts comprising a matrix, optional additives and at least one zeolite. The amount of zeolite is variable but generally ranges from 3 wt% to 60 wt%, often from 6 wt% to 50 wt% and generally from 10 wt% to 45 wt% based on the weight of the catalyst. The zeolite is usually dispersed in the matrix. The amount of additives generally ranges from 0 wt% to 30 wt%, often from 0 wt% to 20 wt% based on the weight of the catalyst. The amount of matrix represents the balance up to 100 wt%. Additives are generally selected from the group formed by oxides of metals from Group IIa of the Periodic Table of the Elements, such as magnesium oxide or calcium oxide, oxides of rare earth metals and titanates of metals from Group IIa. The matrix is generally silica, alumina, silica-alumina, silica-magnesia, clay or a mixture of two or more of these products. The most commonly used zeolite is zeolite Y.

[0158] The cracking is carried out in a substantially vertical reactor, either in an upward mode (riser) or a downward mode (dropper). The choice of catalyst and operating conditions depends on the desired product according to the feedstock to be processed and is as described, for example, on pages 990 - 991 of the paper by M. Marcilly, which was published in revue de l'institut francais du petrole [Review of the French Institute of Petroleums: French Institute of Petroleums Review], Nov.-Dec. 1975, pages 969 - 1006. The operation is usually carried out at a temperature of 450°C to 600°C and a residence time in the reactor of less than 1 minute, often 0.1 to 50 seconds.

[0159] By means of the pretreatment, it is further possible to protect the catalytic cracking catalyst based on zeolite, which is very sensitive to nitrogen, by limiting the nitrogen content at the end of the pretreatment stage.

[0160] (Examples) The following examples demonstrate a significant increase in the activity of HDA and HDN using the specific sequences according to the present invention.

[0161] Examples 1 to 3 describe the preparation of catalysts C1 to C3. In oxide form, the final composition of each catalyst in terms of metals and phosphorus expressed relative to the weight of the catalyst, and also the Ni / W and P / W ratios are shown in Table 1 below.

[0162] Examples 4 to 8 describe the evaluation of the hydrodenitrogenation (HDN) and hydrogenation of aromatic compounds (HDA) of the vacuum distillates of different catalysts C1, C2 and C3 and / or the sequences of catalysts C1, C2 and C3.

[0163] (Example 1: Preparation of an alumina - supported NiMoP catalyst C1) Nickel, molybdenum and phosphorus are added to 100 g of alumina support A1. The loss on ignition of alumina support A1 is 4.1 wt%, the BET specific surface area is 263 m 2 / g, the pore volume is measured by mercury porosimetry and is 0.66 mL / g, the average pore diameter is defined as the volume median diameter by mercury porosimetry and is 9.7 nm, and it is provided in the form of "extrudates". The water absorption of support A1 is 0.72 mL / g. The impregnation solution is prepared by dissolving 32.9 g of molybdenum oxide (Merck®, purity > 99.5 wt%), 10.5 g of nickel hydroxycarbonate (Merck®, purity 99.9 wt%) and 12.78 g of orthophosphoric acid solution (Merck®, 85 wt% in water) in 53.7 mL of distilled water at 90 °C. After dry impregnation, the extrudates are aged by leaving them in a water-saturated atmosphere at ambient temperature for 24 hours and then dried at 90 °C for 16 hours. The impregnated and dried support of catalyst C1 is subsequently added by dry impregnation with a solution containing a mixture of dimethyl succinate (DMSU) and acetic acid (purity 75%). The molar ratios are as follows: DMSU / Mo = 0.85 mol / mol, DMSU / acetic acid = 0.5 mol / mol. The catalyst again undergoes an aging stage at 20 °C for 3 hours under air and then is dried at 120 °C for 3 hours in a cross-flow type oven. The dried catalyst thus obtained is designated as C1. The final composition of catalyst C1, expressed in oxide form, is as follows: MoO3 = 22 ± 0.2 (wt%), NiO = 4.5 ± 0.1 (wt%) and P2O5 = 5.3 ± 0.1 (wt%).

[0164] (Example 2: Preparation of silica-alumina supported NiWP catalyst C2) Nickel, tungsten and phosphorus are added to 100 g of amorphous silica-alumina support ASA1. The loss on ignition of support ASA1 is 1.5 wt%, the BET specific surface area is 240 m 2It is / g, the pore volume is measured by mercury porosimetry and is 0.46 mL / g, the average pore diameter is defined as the volume median diameter by mercury porosimetry and is 7.42 nm, and it is provided in the form of "extrudate". The water absorption of the carrier ASA1 is 0.56 mL / g. The impregnating solution is prepared by dissolving 43.93 g of phosphotungstic acid hydrate (Merck (registered trademark), purity > 99.5 wt%), 2.97 g of phosphoric acid (Merck (registered trademark), 85 wt% in water), and 7.26 g of nickel hydroxycarbonate (Merck (registered trademark), purity > 99.9 wt%) in 48.1 mL of distilled water at 80 °C. After dry impregnation, the extrudates are aged by leaving them in a water-saturated atmosphere at ambient temperature for 24 hours, and then they are dried at 120 °C for 5 hours.

[0165] Subsequently, the impregnated and dried carrier of catalyst C2 is added by dry impregnation with a solution containing an aqueous solution of γ-ketovaleric acid. The molar ratio is as follows: γ-ketovaleric acid / W = 0.8 mol / mol. The catalyst again undergoes an aging step at 20 °C for 3 hours under air, and then it is dried at 120 °C for 3 hours in a cross-flow type oven. The dried catalyst thus obtained is designated as C2.

[0166] The final composition of catalyst C2 is represented in the form of oxides and is as follows: MoO3 = 25 ± 0.2 (wt%), NiO = 3.22 ± 0.1 (wt%), and P2O5 = 1.91 ± 0.1 (wt%).

[0167] (Example 3: Preparation of alumina-supported NiWP catalyst C3) Nickel, tungsten and phosphorus are added to the same support A1 as presented in Example 1. The impregnation solution is prepared by dissolving 48.18 g of phosphotungstic acid hydrate (Merck®, purity > 99.5 wt%), 3.32 g of phosphoric acid (Merck®, 85 wt% in water), and 8.12 g of nickel hydroxycarbonate (Merck®, purity 99.9 wt%) in 69.4 mL of distilled water at 80 °C. After dry impregnation of 100 g of support A1, the extrudates are aged by leaving them in a water-saturated atmosphere at ambient temperature for 24 hours and then dried at 120 °C for 5 hours.

[0168] To the impregnated and dried support of catalyst C3, γ-ketovaleric acid is subsequently added by dry impregnation with a solution containing an aqueous solution of γ-ketovaleric acid. The molar ratio is as follows: γ-ketovaleric acid / W = 0.8 mol / mol. The catalyst again undergoes an aging step at 20 °C for 3 hours under air and then is dried at 120 °C for 3 hours in a cross-flow type oven. The dried catalyst thus obtained is designated as C3.

[0169] The final composition of catalyst C3, expressed in oxide form, is as follows: WO3 = 27 ± 0.2 (wt%), NiO = 3.48 ± 0.1 (wt%) and P2O5 = 2.07 ± 0.1 (wt%).

[0170] [Table 1]

[0171] (Examples 4 - 7: Evaluation of Catalysts C1, C2, and C3 or Sequences of Catalysts C1, C2, and C3 in Hydrodenitrogenation (HDN) of Vacuum Distillate and Hydrogenation (HDA) of Aromatic Compounds) Catalysts and / or sequences of catalysts taken from catalysts C1, C2, and C3 were tested in the hydrodenitrogenation (HDN) of vacuum distillate and the hydrogenation (HDA) of aromatic compounds.

[0172] The feedstock is a vacuum distillate (light vacuum gas oil) resulting from the deep hydrocracking of vacuum residue by the H-Oil (registered trademark) process. The characteristics of the test feedstock used are as follows: density at 15 °C = 0.92 g / cm 3 (NF EN ISO 12185), refractive index at 20 °C = 1.5122 (ASTM D1218-12), sulfur content = 0.59 wt%, nitrogen content = 2720 wt ppm. · Simulated distillation (ASTM D2887) - IP : 240.7 °C; - 10% : 331.5 °C; - 50% : 424.9 °C; - 90% : 539.4 °C; - FP : 600.9 °C

[0173] Tests are carried out in an isothermal pilot-scale reactor having a cross-flow fixed bed, and the fluid flows upward from the bottom. The reactor includes two catalyst zones that allow for the evaluation of different arrangements of catalysts C1, C2, and C3. The feedstock first crosses the first zone filled with the first catalyst and then crosses the second zone filled with the second catalyst.

[0174] According to Example 4 (in accordance with the present invention), the first zone is filled with catalyst C1 (70% of the volume), and then the second zone is filled with catalyst C2 (30% of the volume).

[0175] According to Example 5 (in accordance with the present invention), the first zone is filled with catalyst C1 (50% of the volume), and then the second zone is filled with catalyst C2 (50% of the volume).

[0176] According to Example 6 (not in accordance with the present invention), both zones are filled with catalyst C1 (100% of the volume).

[0177] According to Example 7 (not in accordance with the present invention), both zones are filled with catalyst C2 (100% of the volume).

[0178] According to Example 8 (not in accordance with the present invention), the first region is filled with catalyst C1 (70% of the volume), and then the second region is filled with catalyst C3 (30% of the volume).

[0179] The presulfiding of the catalyst is carried out in situ beforehand at 350 °C in the reactor under pressure with a straight-run distillate gas oil feedstock (density at 15 °C = 0.8491 g / cm 3 (NF EN ISO 12185) and an initial sulfur content = 0.42 wt%) to which 2 wt% of dimethyldisulfide has been added.

[0180] The catalyst tests were carried out under the following operating conditions: total pressure 14 MPa, total volume of the two catalyst regions 9 cm 3 , temperature 390 °C and 415 °C, hydrogen flow rate 15.8 L / h and feedstock flow rate 14.4 cm 3 / h.

[0181] The characteristics of the effluent are analyzed: density at 15 °C (NF EN ISO 12185), refractive index at 20 °C (ASTM D1218-12), simulated distillation (ASTM D2887), sulfur content and nitrogen content. The calculation of the residual content of aromatic carbon is carried out by the n-d-M method (ASTM D3238). The calculation of the degree of hydrogenation of aromatic compounds is carried out as the ratio of the difference between the content of aromatic carbon in the feedstock and the content of aromatic carbon in the effluent to the content of the test feedstock. The calculation of the degree of hydrodenitrogenation is carried out as the ratio of the difference between the nitrogen content in the feedstock and the nitrogen content in the effluent to the nitrogen content of the test feedstock.

[0182] The catalytic performance qualities of the tested catalyst arrays are given in Table 2. They are represented as the relative volume activity (RVA) with respect to 100% of the volume of the reference catalyst C1 (Example 6), assuming 1.2 order for the HDA reaction and 1 order for the HDN reaction.

[0183] Table 2 clearly shows the gains related to the catalytic effect contributed by specific sequences according to the present invention. This is because the sequence of the catalyst according to the present invention enables a significant increase in the volumetric activity in the reactions of hydrodearomatization (HDA) and hydrodenitrogenation (HDN) of the vacuum distillate.

[0184] [Table 2]

Claims

1. A method for hydrogenating hydrocarbon feedstock, wherein the initial boiling point of at least 50% by weight of the hydrocarbon feedstock compound is greater than 300°C, the final boiling point is less than 650°C, the temperature during the hydrogenation treatment is 180°C to 450°C, the pressure is 0.5 to 30 MPa, and the spatiotemporal velocity is 0.1 to 20 h. －１ The hydrogen / feeding ratio is expressed as the volume of hydrogen per unit volume of liquid feeding, measured under standard temperature and pressure conditions, ranging from 50 L / L to 5000 L / L, and the hydrogenated effluent is obtained, comprising the following steps: a) A first hydrogenation step; carried out in a first hydrogenation reaction section; using at least one catalyst bed containing at least one first hydrogenation catalyst; supplying at least a gas stream containing the hydrocarbon feedstock and hydrogen to the hydrogenation reaction section, wherein the first catalyst comprises an alumina support, an active phase consisting of nickel and molybdenum, and an organic compound optionally containing phosphorus and / or optionally oxygen and / or nitrogen and / or sulfur. b) A second hydrogenation step; carried out in a second hydrogenation reaction section; using at least one catalyst bed containing at least one second hydrogenation catalyst; feeding at least a portion of the effluent obtained in step a) to the hydrogenation reaction section; the second catalyst comprising a silica-alumina support, an active phase consisting of nickel and tungsten, phosphorus, and an organic compound containing oxygen and / or nitrogen and / or sulfur.

2. The hydrogenation method according to claim 1, wherein the first hydrogenation reaction section containing the first catalyst occupies a volume V1, and the second hydrogenation reaction section containing the second catalyst occupies a volume V2, and the volume distribution V1 / V2 is 50% / 50% to 90% / 10% in each of the first and second hydrogenation reaction sections.

3. The hydrogenation treatment method according to claim 2, wherein the volume distribution V1 / V2 is 70% by volume / 30% by volume to 80% by volume / 20% by volume in each of the first and second hydrogenation treatment reaction sections.

4. A hydrogenation treatment method according to claim 1, wherein the second catalyst is characterized in the following respects: - The nickel content, expressed in the form of NiO, is 1.2% to 4.5% by weight relative to the total weight of the catalyst. - The tungsten content is WO ３ It is expressed in a form that is 16% to 33% by weight of the total weight of the catalyst. - The phosphorus content is P ２ O ５ It is expressed in form and is present in an amount of 1% to 4% by weight relative to the total weight of the catalyst.

5. A hydrogenation treatment method according to claim 4, wherein the second catalyst is characterized in the following respects: - The nickel content, expressed in the form of NiO, is 1.3% to 4.3% by weight relative to the total weight of the catalyst. - The tungsten content is WO ３ It is expressed in a form that is 17% to 31% by weight of the total weight of the catalyst. - The phosphorus content is P ２ O ５ It is expressed in this form and is present in an amount of 1.3% to 3.4% by weight relative to the total weight of the catalyst.

6. The hydrogenation treatment method according to claim 5 is further characterized in the following respects: - The molar ratio Ni / W is 0.18 to 0.45 mol / mol. - The molar ratio P / W is 0.18 to 0.45 mol / mol.

7. The hydrogenation treatment method according to claim 1, wherein the silica content in the support of the second catalyst is 10% to 50% by weight relative to the total weight of the catalyst.

8. The molybdenum content of the first catalyst is MoO ３ The hydrogenation treatment method according to claim 1, wherein the content is expressed as 5% to 40% by weight relative to the total weight of the catalyst, and the nickel content is expressed as NiO, and is 1% to 10% by weight relative to the total weight of the catalyst.

9. The first catalyst further contains phosphorus, and the phosphorus content is P ２ O ５ represented as, and is 0.1% by weight to 20% by weight based on the total weight of the catalyst. The hydrogenation treatment method according to claim 1.

10. The hydrogenation treatment method according to claim 1, wherein the first catalyst further contains an organic compound containing oxygen and / or nitrogen and / or sulfur.

11. The hydrogenation method according to claim 1, wherein the organic compound is selected from one or more chemical functional groups selected from carboxyl, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, or amide functional groups, or from compounds containing a furan ring, or from sugars.

12. The organic compounds include γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, oxalic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, and di(C) succinate. １ -C ４ Alkyl), more specifically dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinenon, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-flualdehyde (also known as furfural), 5-hydroxymethylfurfural, 2-acetylfuran, 5-methyl-2-flualdehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryl lactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl- The hydrogenation treatment method according to claim 11, wherein the hydrogenation treatment is selected from 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrroridinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate, and dimethyl 3-oxoglutarate.

13. The hydrogenation treatment method according to claim 10, wherein the content of the organic compound is 1% to 30% by weight relative to the total weight of the catalyst.

14. The hydrogenation treatment method according to claim 1, wherein the first and / or second catalyst is at least partially sulfur-based.

15. A hydrogenation treatment method according to any one of claims 1 to 14, to be performed as a pretreatment in a fluidized bed catalytic cracking method.

16. A hydrogenation treatment method according to any one of claims 1 to 14, performed as a pretreatment in a hydrocracking method.