Method for recovering a catalyst from a hydrogenation processing and / or hydrocracking method

Abstract

The present invention relates to a method for regenerating a catalyst comprising a Group VIII metal, a Group VIB metal and a zeolite-free oxide support, the method comprising the steps of: a) regenerating the catalyst at a temperature greater than 360°C and less than 420°C to obtain a regenerated catalyst having a specified carbon and sulfur content, the proportion of crystalline phase being less than 0.6, as determined by X-ray diffraction; b) contacting the regenerated catalyst with an aqueous solution consisting of water, phosphoric acid and an organic acid, each having an acidity constant pKa greater than 1.5; and c) drying at a temperature less than 200°C.

Description

Technical Field

[0001] The present invention relates to a method for the rejuvenation of catalysts for hydrotreating and / or hydrocracking, and to the use of rejuvenated catalysts in the field of hydrotreating and / or hydrocracking.

Background Art

[0002] Generally, the purpose of catalysts for the hydrotreating of hydrocarbon fractions is to remove sulfur-based or nitrogen-based compounds contained therein, for example, to conform petroleum products to the specifications (sulfur content, aromatic compound content, etc.) required for a given use (automobile fuel, gasoline or gas oil, domestic fuel oil, jet fuel).

[0003] Conventional hydrotreating catalysts generally comprise an oxide support, an active phase based on metals from groups VIb and VIII in oxide form, and phosphorus. The preparation of these catalysts generally involves a step of impregnating the support with the metals and phosphorus, followed by a drying operation and a calcination that enables the active phase in the form of their oxides to be obtained. Prior to their use in the reactions of hydrotreating and / or hydrocracking, these catalysts are generally subjected to sulfidation to form the active entities.

[0004] The addition of organic compounds to these to improve the activity of hydrotreating catalysts has been recommended by those skilled in the art, particularly for catalysts prepared by impregnation and subsequent drying operations without subsequent calcination. These catalysts are often referred to as "additive-impregnated dried catalysts".

[0005] During the operation of the hydrotreating and / or hydrocracking process, the catalyst is deactivated by the accumulation of coke and / or sulfur-based compounds or compounds containing other heteroelements on the surface of the catalyst. Therefore, after a certain period, its replacement is consequently necessary.

[0006] To counter these drawbacks, the regeneration of catalysts for the hydroprocessing of middle distillates or spent residues is an economically and ecologically advantageous way, as it enables these catalysts to be reused in an industrial unit, rather than landfilling or recycling (metal recovery) them. However, regenerated catalysts generally have lower activity than the starting catalysts.

[0007] To overcome the deficiency in the hydrodesulfurization activity of the regenerated catalyst, it is possible to apply an additional "rejuvenation" treatment. The rejuvenation method consists of re-impregnating the regenerated catalyst with a solution containing a metal precursor, in the presence or absence of organic or inorganic additives. These "rejuvenation" methods are well known to those skilled in the art in the field of middle distillates. Many patents, for example, patents 1 to 10, therefore, provide different methods for performing the rejuvenation of catalysts for the hydroprocessing of middle distillates.

[0008] Patent document 3 describes a rejuvenation method in which a catalyst containing oxides of metals from group VIb and oxides of metals from group VIII is contacted with an acid and an organic additive, the boiling point of which is from 80 °C to 500 °C, the solubility in water is at least 5 grams / liter (20 °C, atmospheric pressure), and in some cases, a drying operation is carried out under conditions such that at least 50% of the additive is maintained in the catalyst. The hydroprocessing catalyst can be a fresh hydroprocessing catalyst or a regenerated spent hydroprocessing catalyst.

[0009] Patent document 11 states that a catalyst containing oxides of metals from group VIb and oxides of metals from group VIII is treated with phosphoric acid and an acidity constant pK aIt is contacted with an organic acid having a value greater than 1.5 respectively, and then a drying operation is performed at a temperature below 200 °C, but no subsequent firing is carried out. A recovery method is described. The regeneration is carried out in advance at a temperature of 300 °C to 500 °C, preferably 420 °C to 500 °C. More specifically, Patent Document 11 discloses that phosphoric acid and an organic acid having an acidity constant pK a each greater than 1.5, preferably greater than 3.5, that is, an organic acid that is not too strong, in combination, makes it possible to observe a synergistic effect at a catalytic activity level that cannot be predicted when phosphoric acid or the organic acid is used alone.

[0010] An object of the present invention is to provide an improvement to the recovery method described in Patent Document 11 by performing regeneration controlled within an accurate temperature range.

Prior Art Documents

Patent Documents

[0011]

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

Patent Document 10

Patent Document 11

Summary of the Invention

Means for Solving the Problems

[0012] (Subject of the Invention) The present invention relates to a method for the recovery of at least partially spent catalysts obtained from a hydrotreating and / or hydrocracking process, said at least partially spent catalyst being obtained from a fresh catalyst containing at least one metal from Group VIII, at least one metal from Group VIb, a non-zeolite-containing support, and optionally phosphorus, said method comprising the following steps: a) The at least partially spent catalyst is regenerated in a stream of oxygen-containing gas at a temperature between 360 °C and less than 420 °C; a regenerated catalyst is obtained; the regenerated catalyst contains carbon, the content of which is 0.1% to 0.5% by weight, contains sulfur, the content of which is 0.3% to 0.8% by weight, and the proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction and is characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak at 45.7° 2θ characteristic of alumina and is less than 0.6. b) Then, the regenerated catalyst is contacted with an aqueous solution consisting of water, phosphoric acid, and an organic acid having an acidity constant pK a greater than 1.5. c) A drying step; carried out at a temperature of less than 200 °C; and not calcined thereafter; a recovered catalyst is obtained.

[0013] Generally, regeneration is carried out to remove the coke and / or sulfur-based compounds and / or other heteroelements accumulated in it during the use of the catalyst. The disappearance of coke and other impurities by regeneration makes it possible to relieve the blockage of the pores of the catalyst, and thus makes the active phase accessible to the feedstock again. The higher the regeneration temperature, the lower the content of coke and other impurities.

[0014] However, regeneration at too high a temperature results in the appearance of a crystalline phase resulting from at least one metal from Group VIII and at least one metal from Group VIb (for example, nickel molybdate NiMoO4 and / or cobalt molybdate CoMoO4), which is formed by the sintering of the oxide precursor of the active phase composed of a metal from Group VIII and / or a metal from Group VIb. The formation of such a crystalline phase is undesirable because it results in a catalytically inactive entity after activation by sulfidation.

[0015] The choice of regeneration temperature is, therefore, contradictory. On the one hand, the temperature must be high enough to remove the coke and / or other impurities to make the active phase freely accessible, and on the other hand, the temperature must not be too high to avoid the formation of the crystalline phase. The regeneration temperature conditions are, therefore, such that the regenerated catalyst obtained contains 0.1 wt% to 0.5 wt% of carbon, 0.3 wt% to 0.8 wt% of sulfur, and the proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction and characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ and is less than 0.6. The regeneration temperature conditions that make it possible to obtain such a solid are between 360 °C and less than 420 °C.

[0016] Containing 0.1 wt% to 0.5 wt% carbon and 0.3 wt% to 0.8 wt% sulfur, the proportion of the crystalline phase obtained from at least one metal of Group VIII and at least one metal of Group VIb is characterized by the ratio being less than 0.6. The recovery in the presence of two specific acids used on a regenerated catalyst is achieved by regeneration at a temperature between 360 °C and less than 420 °C. The proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction and is characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ, resulting in a solid that is less than 0.4. Such recovery, therefore, enables good dissolution of the crystalline phase and dispersion of the metal phase, resulting in a dispersion close to that of a fresh catalyst and, therefore, an activity close to that of a fresh catalyst, which applies to cases where it is not necessary to add the metal of the active phase.

[0017] This is because the applicant's company has observed that by implementing this recovery method, it is possible to obtain a hydrotreating and / or hydrocracking catalyst with improved catalyst performance quality compared to the recovered catalyst starting from a regenerated catalyst that does not meet the combined characteristics of carbon, sulfur content, and crystalline phase.

[0018] By means of controlled regeneration, the catalyst performance quality is improved such that the addition of metal is not required during recovery.

[0019] An improvement in catalyst performance quality can be observed in cobalt-based or nickel-based catalysts, but very particularly in nickel-based catalysts.

[0020] Typically, due to the improvement in activity, the temperature required to achieve the desired sulfur or nitrogen content (e.g., 10 ppm sulfur in the case of the gas oil feedstock in the ULSD, i.e., Ultra Low Sulfur Diesel mode) is close to the temperature of the fresh catalyst.

[0021] According to one alternative form, the temperature in step a) is 380 °C to 410 °C.

[0022] According to one alternative form, the proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction and is characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ in step a) to the surface area of the peak characteristic of alumina at 45.7° 2θ and is less than 0.50.

[0023] According to one alternative form, the organic acid used in step b) is selected from acetic acid, maleic acid, malic acid, malonic acid, gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, lactic acid, pyruvic acid, ascorbic acid or succinic acid.

[0024] According to one alternative form, the organic acid used in step b) is an organic acid with an acidity constant pK a greater than 3.5.

[0025] According to one alternative form, the organic acid used in step b) is selected from gluconic acid, γ-ketovaleric acid, lactic acid, pyruvic acid, ascorbic acid or succinic acid.

[0026] According to one alternative form, the molar ratio of the added organic acid per metal to the metal from Group VIb present in the regenerated catalyst is 0.01 to 5 mol / mol.

[0027] According to one alternative form, the molar ratio of phosphorus added per metal from group VIb already present in the regenerated catalyst is between 0.01 and 5 mol / mol.

[0028] According to one alternative form, the content of metals from group VIb of the fresh catalyst is between 1% and 40% by weight of oxide of said metals from group VIb relative to the weight of the catalyst, and the total content of metals from group VIII is between 1% and 10% by weight of oxide of said metals from group VIII relative to the weight of the catalyst.

[0029] According to one alternative form, the fresh catalyst contains phosphorus, the total phosphorus content being between 0.1% and 20% by weight, expressed as P2O5, relative to the total weight of the catalyst.

[0030] According to one alternative form, the zeolite-free oxide support is chosen from alumina, silica, silica-alumina or also oxides of titanium or magnesium, used alone or in a mixture with alumina or silica-alumina.

[0031] According to one alternative form, the rerecovered catalyst resulting from step c) comprises a proportion of crystalline phases resulting from at least one metal from group VIII and at least one metal from group VIb, the proportion of crystalline phases being determined by X-ray diffraction and characterized by the ratio of the surface area of the crystalline diffraction peak at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ being less than 0.4.

[0032] According to one alternative form, the regeneration step a) is preceded by a deoiling step which comprises contacting an at least partially spent catalyst resulting from a hydrotreating and / or hydrocracking process with a stream of inert gas at a temperature between 300° C. and 400° C.

[0033] According to one alternative form, the rerecovered catalyst is subjected to a sulphurization step after step c).

[0034] The present invention also relates to the use of a recycled catalyst prepared according to the method of the present invention in a process for the hydrotreating and / or hydrocracking of hydrocarbon fractions.

[0035] According to the present invention, the expressions "of between A and B" and "between A and B" are synonymous and mean that both limit values (A, B) of the interval are included in the described range of values. If not, and if both limit values are not included in the described range, such clarification will be introduced by the present invention.

[0036] Within the scope of the present invention, ranges of various 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 present invention, a range of suitable pressure values can be combined with a range of more suitable temperature values.

[0037] Subsequently, specific and / or preferred embodiments of the present invention are described. They can be implemented separately or in combination with each other, and there is no limitation to this combination if the combination is technically feasible.

[0038] Subsequently, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC Press, editor-in-chief D.R. Lide, 81st edition, 2000 - 2001). For example, Group VIII (or Group VIIIb) according to the CAS classification corresponds to the metals in columns 8, 9 and 10 according to the new IUPAC classification.

[0039] According to the present invention, the pressure is absolute pressure, also denoted as abs., and is given in MPa (absolute) (MPa absolute) (or absolute MPa (MPa abs.)) unless otherwise specifically indicated.

[0040] The metal content is measured by X-ray fluorescence.

[0041] The hydrotreating is understood to mean reactions that include in particular hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrogenation of aromatic compounds (HOA).

DETAILED DESCRIPTION OF THE INVENTION

[0042] (Description of the Invention) The recycled catalyst obtained by the method according to the invention is used in a process for the hydrotreating and / or hydrocracking of hydrocarbon fractions over a period of time, exhibits significantly lower activity than a fresh catalyst and requires its replacement, and results from at least partially spent catalysts (which themselves result from fresh catalysts).

[0043] (Fresh Catalyst) Fresh catalysts used in processes for the hydrotreating and / or hydrocracking of hydrocarbon fractions are known to those skilled in the art. It contains at least one metal from Group VIII, at least one metal from Group VIb, an oxide support that does not contain zeolite, and optionally phosphorus and / or organic compounds as described below.

[0044] The metal from Group VIb present in the active phase of the fresh catalyst is preferably selected from molybdenum and tungsten. The metal from Group VIII present in the active phase of the fresh catalyst is preferably selected from cobalt, nickel and mixtures of these two elements. The active phase of the fresh catalyst is preferably selected from the group formed by the elemental combinations of nickel-molybdenum, cobalt-molybdenum, nickel-tungsten, nickel-molybdenum-tungsten and nickel-cobalt-molybdenum, and most preferably, the active phase consists of the combination of cobalt and molybdenum, nickel and molybdenum, nickel and tungsten or nickel-molybdenum-tungsten. Particularly preferably, the active phase consists of nickel and molybdenum.

[0045] The content of the metal from Group VIII, expressed as the oxide of the metal from Group VIII, is 1 wt% to 10 wt%, preferably 1.5 wt% to 9 wt%, more preferably 2 wt% to 8 wt% based on the total weight of the fresh catalyst.

[0046] The content of the metal from Group VIb, expressed as the oxide of the metal from Group VIb, is 1 wt% to 40 wt%, preferably 1 wt% to 35 wt%, more preferably 2 wt% to 30 wt% based on the total weight of the fresh catalyst.

[0047] The molar ratio of the metal from Group VIII to the metal from Group VIb in the fresh catalyst is generally 0.1 to 0.8, preferably 0.15 to 0.6.

[0048] In some cases, the phosphorus content of the fresh catalyst can further be shown to be generally 0.1 wt% to 20 wt% by weight of P2O5, preferably 0.2 wt% to 15 wt% by weight of P2O5, most preferably 0.3 wt% to 11 wt% by weight of P2O5 based on the total weight of the fresh catalyst. For example, the phosphorus present in the fresh catalyst is combined in the form of a heteropolyanion with the metal from Group VIb and, in some cases, the metal from Group VIII.

[0049] Furthermore, the molar ratio of phosphorus / (metal from Group VIb) is generally from 0.08 to 1, preferably from 0.1 to 0.9, very preferably from 0.15 to 0.8.

[0050] The oxide carrier without zeolite in the fresh catalyst is usually a porous solid and is selected from the group consisting of: alumina, silica, silica - alumina, or oxides of titanium and magnesium; the oxides of titanium and magnesium are used alone or as a mixture with alumina or silica - alumina. Preferably, the oxide carrier without zeolite is a carrier based on alumina or silica or silica - alumina.

[0051] When the oxide carrier without zeolite is based on alumina, it contains more than 50% by weight of alumina relative to the total weight of the carrier and generally contains only alumina or silica - alumina as defined below.

[0052] Preferably, the oxide carrier without zeolite contains alumina and preferably extruded alumina. Preferably, the alumina is gamma - alumina.

[0053] The total pore volume of the alumina carrier is advantageously from 0.1 to 1.5 cm 3 ·g -1 , preferably from 0.4 to 1.1 cm 3 ·g -1 . 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.

[0054] The specific surface area of the alumina support is preferably 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.

[0055] In another preferred case, the oxide support is silica-alumina containing at least 50% by weight of alumina based on the total weight of the support. The silica content in the support is at most 50% by weight, generally 45% by weight or less, preferably 40% by weight or less, based on the total weight of the support.

[0056] 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.

[0057] When the support for the catalyst is silica-based, it contains more than 50% by weight of silica based on the total weight of the support, and generally it contains only silica.

[0058] According to a particularly preferred alternative form, the oxide support consists of alumina, silica or silica-alumina.

[0059] The support is preferably provided in the form of beads, extrudates, pellets or irregular non-spherical aggregates, and the specific shape can result from the crushing stage.

[0060] The fresh catalyst can further contain at least one organic compound containing oxygen and / or nitrogen and / or sulfur (before sulfidation). Such additives are known. Generally, the organic compound is a compound containing one or more chemical functional groups selected from the functional groups of carboxylic acid, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea and amide, or a compound containing a furan ring or a sugar.

[0061] The oxygen-containing organic compound can be one or more compounds containing one or more chemical functional groups selected from the functional groups of carboxyl, alcohol, ether, aldehyde, ketone, ester or carbonate, or also a compound containing a furan ring, or also one or more selected from sugars. As examples, the oxygen-containing organic compound is ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (molecular weight 200 to 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, maleic acid, malic acid, malonic acid, oxalic acid, gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, di(C1-C4 alkyl) succinate, 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-butyrolactone, 2-acetylbutyrolactone, propylene carbonate, 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, methyl 2-furoate, furfuryl alcohol (also known under the name of furfuranol), furfuryl acetate, ascorbic acid, butyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, methyl 3-methoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and 5-methyl-2(3H)-furanone, and can be one or more selected from the group consisting of them.

[0062] 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. 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.

[0063] The organic compound containing oxygen and nitrogen can be one or more selected from compounds containing one or more chemical functional groups selected from carboxylic acid, alcohol, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, amide, urea, or oxime functional groups. As an example, the organic compound containing oxygen and nitrogen 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, cyanoacetic acid 2-methoxyethyl, 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.

[0064] The sulfur-containing organic compound 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 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, methyl 3-(methylthio)propanoate and ethyl 3-(methylthio)propanoate.

[0065] Preferably, the organic compound contains oxygen, and preferably, it contains only oxygen as a heteroatom. Preferably, it is γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, gluconic acid, dimethyl succinate, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, 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 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone and 4-aminobutanoic acid.

[0066] The content rate of one or more organic compounds containing oxygen and / or nitrogen and / or sulfur on the fresh catalyst is 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 fresh catalyst.

[0067] The preparation of the fresh catalyst is known and generally includes the step of impregnating a zeolite-free oxide carrier with metals of Group VIII and Group VIb, and optionally phosphorus and / or organic compounds, followed by a drying operation, and then an optional calcination is carried out to obtain the active phase in the form of an oxide. Before its use in a process for the hydrotreatment and / or hydrocracking of hydrocarbon fractions, the fresh catalyst is generally subjected to sulfidation to form the active entities as described below.

[0068] The impregnation step in the preparation of the fresh catalyst can be carried out by any of slurry impregnation, or excess impregnation, or dry impregnation, or any other means known to those skilled in the art.

[0069] Examples of sources of molybdenum that may be used include 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 any heteropoly compound, for example, those of the Keggin, defective Keggin, substituted Keggin, Dawson, Anderson or Strandberg type. Preferred for use are molybdenum trioxide and Keggin, defective Keggin, substituted Keggin and Strandberg type heteropolyanions.

[0070] 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 any heteropoly compound, for example, those 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.

[0071] Cobalt precursors that can be used are advantageously selected, for example, from oxides, hydroxides, hydroxycarbonates, carbonates and nitrates. Preferably used are cobalt hydroxide and cobalt carbonate.

[0072] Nickel precursors that can be used are advantageously selected, for example, from oxides, hydroxides, hydroxycarbonates, carbonates and nitrates. Preferably used are nickel hydroxide and nickel hydroxycarbonate.

[0073] A suitable phosphorus precursor is orthophosphoric acid H3PO4, but its salts and esters, such as ammonium phosphate, are also suitable. Phosphorus can also be introduced in the form of a heteropolyanion of the Keggin, defective Keggin, substituted Keggin or Strandberg type, together with one or more elements from Group VIb.

[0074] The impregnation stage includes several embodiments. They are distinguished in particular by the point in time at which the organic compound is introduced when it is present, and this introduction can be carried out simultaneously (co-impregnation), or subsequently (post-impregnation), or before (pre-impregnation) the impregnation of the compound containing a metal from Group VIb. Furthermore, it is possible to combine the embodiments.

[0075] Advantageously, after each impregnation stage, regardless of whether this is an impregnation stage with a metal and optionally phosphorus or an organic compound, the impregnated support is left to age.

[0076] Any aging stage is advantageously 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 time of 10 minutes to 48 hours, preferably 30 minutes to 6 hours, is sufficient.

[0077] The impregnation solution can contain any polar solvent known to those skilled in the art. The polar solvent used is advantageously selected from the group formed by methanol, ethanol, water, phenol and cyclohexanol, which are used alone or as a mixture. The polar solvent can also advantageously be selected from the group formed by propylene carbonate, DMSO (dimethyl sulfoxide), N-methylpyrrolidone (NMP) and sulfolane, and is 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.

[0078] After the impregnation stage and any optional aging stage, the catalyst is subjected to a drying stage at a temperature below 200 °C, preferably between 50 °C and 180 °C, more preferably between 70 °C and 150 °C, and most preferably between 75 °C and 130 °C, without a subsequent calcination stage. The drying stage is preferably carried out under an inert atmosphere or an oxygen-containing atmosphere.

[0079] According to an alternative form of the invention, which is suitable when organic compounds are present, the fresh catalyst has not been calcined during its preparation, i.e., the impregnated catalyst precursor has not been subjected to a heat treatment step at a temperature above 200 °C in the presence or absence of water, under an inert atmosphere or an oxygen-containing atmosphere.

[0080] According to another alternative form of the invention, the fresh catalyst has been subjected to a calcination stage during its preparation, i.e., the impregnated catalyst precursor has been subjected to a heat treatment step at a temperature between 200 °C and 1000 °C, preferably between 250 °C and 750 °C, typically for a period between 15 minutes and 10 hours, in the presence or absence of water, under an inert atmosphere or an oxygen-containing atmosphere.

[0081] During the process for the hydrotreating and / or hydrocracking of hydrocarbon fractions, coke and sulfur, as well as other contaminants resulting from the feedstock, such as silicon, arsenic, and metals, are formed and / or deposited on the catalyst, converting the fresh catalyst into at least a partially spent catalyst.

[0082] The at least partially spent catalyst is understood to mean a catalyst that has emerged from a hydrotreating process carried out under the conditions described below and has not been subjected to a heat treatment at a temperature above 200 °C under a gas containing air or oxygen (which is often also known as the regeneration stage). It may have undergone desulfurization.

[0083] The at least partially spent catalyst consists of an oxide support that does not contain zeolite, an active phase formed from at least one metal from Group VIb and at least one metal from Group VIII, and optionally phosphorus from a fresh catalyst, and carbon, sulfur, and optionally other contaminants resulting from the feedstock, such as silicon, arsenic, and metals.

[0084] The content of metals from Group VIb, metals from Group VIII, and phosphorus in fresh, at least partially spent, regenerated or recovered catalysts is expressed as oxides after correction for the loss on ignition of the catalyst sample over 2 hours at 550 °C in a muffle furnace. The loss on ignition is due to the loss of moisture, carbon, sulfur, and / or other contaminants. It is determined according to ASTM D7348.

[0085] The content of metals from Group VIb, metals from Group VIII, and optional phosphorus in the at least partially spent catalyst is substantially the same as that of the fresh catalyst from which it originated. The term "substantially the same" is understood to mean that each of the metal elements mentioned is present in a relative proportion within 5% of that in the original fresh catalyst.

[0086] It should be noted that the term "coke" or "carbon" in this patent application refers to a hydrocarbon-based substance that accumulates on the surface of a hydrotreating catalyst that has been at least partially spent during its use, is highly cyclized and condensed, and has an appearance similar to graphite.

[0087] The at least partially spent catalyst contains carbon, in particular, and its content is generally 2 wt% or more, preferably 2 wt% - 25 wt%, more preferably 4 wt% - 16 wt% based on the total weight of the at least partially spent catalyst.

[0088] The at least partially spent catalyst contains sulfur, in particular, and its content is generally 2% by weight or more, preferably 2% to 25% by weight, more preferably 4% to 16% by weight, based on the total weight of the at least partially spent catalyst.

[0089] (Regeneration (stage a)) The method for the recovery of the at least partially spent catalyst according to the present invention includes a step of removing coke and sulfur (regeneration step). According to step a) of the method according to the present invention, the at least partially spent catalyst is regenerated at a temperature between 360 °C and less than 420 °C in an oxygen-containing gas stream, and contains carbon with a content of 0.1% to 0.5% by weight and sulfur with a content of 0.3% to 0.8% by weight. The proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction and is characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ, which is less than 0.6, in order to obtain a regenerated catalyst.

[0090] Even if this is possible, regeneration is preferably not carried out by holding the supported catalyst in a hydrotreating reactor (in situ regeneration). Preferably, the at least partially spent catalyst is therefore removed from the reactor and sent to a regeneration plant for regeneration in the said plant (ex situ regeneration).

[0091] The regeneration step a) is preferably preceded by a deoiling step. The deoiling step generally includes bringing the at least partially spent catalyst into contact with a flow of inert gas (i.e., essentially lacking oxygen), for example, in a nitrogen atmosphere, at a temperature of 300 °C to 400 °C, preferably 300 °C to 350 °C. The flow rate of the inert gas with respect to the flow rate per unit volume of the catalyst is 5 to 150 SL·L -1 ·h -1 for 3 to 7 hours.

[0092] In an alternative form, the dewaxing step can be carried out by light hydrocarbons, by steam treatment or by any other similar method.

[0093] The dewaxing step makes it possible to remove soluble hydrocarbons that may prove dangerous in the regeneration step to show a risk of flammability in an oxidizing atmosphere.

[0094] The regeneration step a) is generally carried out in a stream of oxygen-containing gas, generally air. The water content is generally from 0 wt% to 50 wt%. The gas flow rate with respect to the flow rate per unit volume of the at least partially spent catalyst is preferably 20 - 2000 SL·L -1 ·h -1 , more preferably 30 - 1000 SL·L -1 ·h -1 , particularly preferably 40 - 500 SL·L -1 ·h -1 . The duration of the regeneration is preferably 2 hours or more, more preferably 2.5 hours or more, particularly preferably 3 hours or more. The temperature at which the regeneration of the at least partially spent catalyst is carried out is generally between 360 °C and less than 420 °C, preferably 360 °C - 415 °C, suitably 360 °C - 410 °C, or also 380 °C - 410 °C.

[0095] The regeneration step a) can be carried out, for example, in a cross-flow bed, a swept bed or a static atmosphere. For example, the oven used can be a rotary rotary oven or a vertical oven or a band oven equipped with a radial traverse layer.

[0096] This is because the temperature is important to be high enough to remove coke and / or other impurities to have free access to the active phase, and at the same time it must not be too high to avoid the formation of a crystalline phase.

[0097] The regenerated catalyst is composed of an oxide support that does not contain zeolite, an active phase formed from at least one metal from Group VIb and at least one metal from Group VIII, and optionally phosphorus from the fresh catalyst. After regeneration, the hydrogenation functional bodies containing the Group VIb and Group VIII metals of the regenerated catalyst are in the form of oxides.

[0098] The contents of the metal from Group VIb, the metal from Group VIII, and optionally phosphorus in the regenerated catalyst are substantially the same as the contents of the at least partially spent catalyst and the resulting fresh catalyst. The term "substantially the same" is understood to mean that each of the mentioned metal elements is present in the same proportion within 5% relative to that in the initial fresh catalyst.

[0099] The regenerated catalyst has a specific surface area of 5 - 400 m 2 / g, preferably 10 - 350 m 2 / g, preferably 40 - 350 m 2 / g, most preferably 150 - 340 m 2 / g.

[0100] The pore volume of the regenerated catalyst is generally 0.1 cm 3 / g - 1.5 cm 3 / g, preferably 0.3 cm 3 / g - 1.1 cm 3 / g.

[0101] The regenerated catalyst obtained in regeneration step a) contains residual carbon, and its content is 0.1 wt% - 0.5 wt% based on the total weight of the regenerated catalyst, preferably 0.1 wt% - 0.49 wt% based on the total weight of the regenerated catalyst, preferentially 0.1 wt% - 0.45 wt%, and particularly preferably 0.1 wt% - 0.4 wt%.

[0102] It should be noted that the term "residual carbon" in this patent application means the carbon (coke) remaining in the catalyst regenerated after the regeneration of the used hydrotreating catalyst. This residual carbon content in the regenerated hydrotreating catalyst is measured by elemental analysis according to the standard ASTM D5373.

[0103] The regenerated catalyst can contain residual sulfur, and its content is 0.3 wt% to 0.8 wt% based on the total weight of the regenerated catalyst, preferably 0.3 wt% to 0.75 wt% based on the total weight of the regenerated catalyst, preferentially 0.4 wt% to 0.75 wt%, and particularly preferably 0.4 wt% to 0.7 wt%. This residual sulfur content in the regenerated hydrotreating catalyst is measured by elemental analysis according to ASTM D5373.

[0104] Actually, surprisingly, regeneration at a relatively low regeneration temperature makes it possible to obtain a regenerated catalyst containing only very little sulfur and / or residual carbon. A relatively low sulfur and / or residual carbon content is important for free access to the active phase.

[0105] During the regeneration stage, a part of the active phase can form a crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb. The crystalline phase can be a single crystalline compound or a mixture of different crystalline compounds. Depending on the metal composition of the catalyst, different crystalline compounds can be formed, for example, nickel molybdate NiMoO4, cobalt molybdate CoMoO4, nickel tungstate NiWO4 or cobalt tungstate CoWO4; mixtures of these or mixed metal crystals can also be formed.

[0106] The formation of such a crystalline phase is not desirable because it results in a catalytically inactive entity after activation by sulfidation and thus indicates a loss of the active phase.

[0107] The proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb is characterized by a ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ of less than 0.6, preferably less than 0.55, and suitably less than 0.5. The regenerated catalyst may not contain a crystalline phase.

[0108] The content of the crystalline phase is measured by X-ray diffraction (XRD). The diffraction pattern is obtained using the conventional powder method with the Kα1 line of copper (λ = 1.5406 Å) by a diffractometer. From the position of the diffraction peak represented by the angle 2θ, the interplanar distance d that is characteristic of the crystalline phase and enables identification based on an existing database (COD Crystallography Open Database, ICDD International Center for Diffraction Data) hkl is calculated by Bragg's relation. The measurement error Δ(d hkl ) with respect to d hkl is calculated as a function of the absolute error Δ(2θ) assigned to the measurement of 2θ by Bragg's law. The absolute error Δ(2θ) is ±0.5°. The relative area A hkl assigned to each d rel value is measured by integrating the corresponding diffraction peak after subtraction of the baseline. Software for baseline integration and subtraction is known and has been conventionally used by those skilled in the art.

[0109] The proportion of the crystalline phase is evaluated by evaluating the ratio of the surface area of the diffraction peak of a crystal, such as nickel molybdate (26.6° 2θ) or cobalt molybdate (also 26.6° 2θ), to the surface area of the peak characteristic of alumina (e.g., 45.7° 2θ for γ-alumina) relative to the signal of alumina from the X-ray diffraction pattern, and the surface area is calculated after subtraction of the baseline of the diffraction pattern.

[0110] In some cases, the regenerated catalyst can further exhibit low levels of contaminants resulting from the feedstock processed by the fresh catalyst from which it originated, such as silicon, arsenic, and metals such as nickel, vanadium, or iron.

[0111] Preferably, the silicon content (excluding what may be present on the fresh catalyst) is less than 2% by weight, more preferably less than 1% by weight, based on the total weight of the regenerated catalyst.

[0112] Preferably, the arsenic content is less than 2000 ppm by weight, more preferably less than 1000 ppm by weight, based on the total weight of the regenerated catalyst.

[0113] Preferably, for each of nickel, vanadium, or iron, which are metals, the content is less than 1% by weight, more preferably less than 5000 ppm by weight, based on the total weight of the regenerated catalyst.

[0114] (Recovery (stage b)) The recovery method according to the present invention includes stage b) after the regeneration stage a), according to which the regenerated catalyst is contacted with an aqueous solution consisting of water, phosphoric acid, and an organic acid, and each acidity constant pK a is greater than 1.5, preferably greater than 3.5.

[0115] The organic acid can contain one or more carboxylic acid functional groups, and each acidity constant is greater than 1.5, preferably greater than 3.0, particularly preferably greater than 3.5. The acidity constant is measured at 25 °C in water. The organic acid can contain, in addition to one or more carboxylic acid functional groups, other chemical functional groups of the alcohol, ether, aldehyde, ketone, or ester type.

[0116] The organic acid is preferably selected from acetic acid, maleic acid, malic acid, malonic acid, gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, lactic acid, pyruvic acid, ascorbic acid or succinic acid. Preferably, the organic acid is selected from citric acid, acetic acid, gluconic acid, γ-ketovaleric acid, lactic acid, ascorbic acid and succinic acid.

[0117] Particularly preferably, the acid is an organic acid having an acidity constant pK a greater than 3.5. Preferably, the organic acid is selected from gluconic acid, γ-ketovaleric acid, lactic acid, ascorbic acid or succinic acid.

[0118] These acids have the following acidity constants: Acetic acid pK a = 4.76 Maleic acid pK a1 = 1.89 pK a2 = 6.23 Malic acid pK a1 = 3.46 pK a2 = 5.10 Malonic acid pK a1 = 2.85 pK a2 = 5.70 Gluconic acid pK a = 3.86 Tartaric acid pK a1 = 2.50 pK a2 = 4.20 Citric acid pK a1 = 3.13 pK a2 = 4.76 pK a3 = 6.40 γ-Ketovaleric acid pK a1 = 4.64 Lactic acid pK a = 3.86 Pyruvic acid pK a = 2.49 Ascorbic acid pK a1 = 4.10 pK a2 = 11.80 Succinic acid pK a1 = 4.21 pK a2 = 5.64

[0119] The organic acid is advantageously introduced into the impregnation aqueous solution in an amount corresponding to the following: - Molar ratio of added organic acid / metal from Group VIb per one or more metals from Group VIb present in the regenerated catalyst: 0.01 to 5 mol / mol, preferably 0.05 to 3 mol / mol, suitably 0.05 to 2 mol / mol, very preferably 0.1 to 1.5 mol / mol, and - Molar ratio of added organic acid / metal from Group VIII per one or more metals from Group VIII present in the regenerated catalyst: 0.02 to 17 mol / mol, preferably 0.1 to 10 mol / mol, suitably 0.15 to 5 mol / mol, very preferably 0.2 to 3.5 mol / mol.

[0120] When several organic acids are present, different molar ratios apply to each of the organic acids present.

[0121] Regarding phosphoric acid, this is advantageously introduced into the impregnation aqueous solution in an amount corresponding to a molar ratio of added phosphorus per metal from Group VIb already present in the regenerated catalyst: 0.01 to 5 mol / mol, preferably 0.05 to 3 mol / mol, suitably 0.05 to 2 mol / mol, very preferably 0.1 to 1.5 mol / mol.

[0122] The contacting step b) can be carried out by slurry impregnation, or by excess impregnation, or by dry impregnation, or by all other means known to those skilled in the art.

[0123] Equilibrium (or excess) impregnation consists of immersing the support or catalyst in a volume of solution (often considerably) larger than the pore volume of the support or catalyst, while maintaining the system agitated to improve the exchange between the solution and the support or catalyst. Equilibrium is finally achieved after diffusion into the pores of the support or catalyst of different entities. Control of the amount of element to be deposited is provided by prior measurement of the adsorption isotherm that relates the concentration of the element to be deposited contained in the solution to the amount of element deposited on the solid in equilibrium with this solution.

[0124] Dry impregnation consists, in part, of introducing an impregnating liquid in a volume equal to the pore volume of the support or catalyst. Dry impregnation makes it possible to deposit all of the components contained in the impregnating liquid on a given support or catalyst.

[0125] Step b) can advantageously be carried out using the impregnating solution, by one or more excess impregnations of the solution, or preferably by one or more dry impregnations, most preferably by a single dry impregnation of at least a partially spent catalyst previously regenerated in step a).

[0126] Phosphoric acid and the organic acid can be introduced together in a single impregnation step (co-impregnation) or independently in several impregnation steps, which can be in any order.

[0127] Advantageously, after each impregnation step, the impregnated regenerated catalyst is aged by leaving it to stand. Aging makes it possible for the impregnating solution to be uniformly dispersed within the regenerated catalyst.

[0128] Any aging step is advantageously carried out at atmospheric pressure, in a water-saturated atmosphere, at a temperature between 17 °C and 50 °C, preferably at ambient temperature. In general, an aging time of from 10 minutes to 48 hours, preferably from 30 minutes to 15 hours, and most preferably from 30 minutes to 6 hours is sufficient.

[0129] When several impregnation steps are carried out, after each impregnation step, an intermediate drying step is carried out, and the temperature at that time is preferably less than 200 °C, advantageously 50 °C to 180 °C, preferably 70 °C to 150 °C, very preferably 75 °C to 130 °C. In some cases, a ripening period is observed between the impregnation step and the intermediate drying step.

[0130] (Drying (Step c)) After the reactivation step, the catalyst is subjected to a drying step, and the temperature at that time is less than 200 °C, advantageously 50 °C to 180 °C, preferably 70 °C to 150 °C, very preferably 75 °C to 130 °C, and subsequently the calcination step is not carried out.

[0131] The drying step is preferably carried out under an inert atmosphere or an oxygen-containing atmosphere.

[0132] The drying step can be carried out by any technique known to those skilled in the art. It is advantageously carried out at atmospheric pressure or reduced pressure. Preferably, this step is carried out at atmospheric pressure. It is advantageously carried out in a cross-flow 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 cross-flow bed in the presence of nitrogen and / or air. Preferably, the duration of the drying step is 5 minutes to 4 hours, preferably 30 minutes to 4 hours, very preferably 1 hour to 3 hours.

[0133] Drying is preferably carried out so as to retain at least 30% by weight of the organic acid introduced during the impregnation step; preferably, this amount is calculated based on the carbon remaining on the reactivated catalyst and is more than 50% by weight, even more preferably more than 70% by weight.

[0134] It is important to emphasize that the rerecovered catalyst is not subjected to calcination after the introduction of phosphoric acid and organic acid in order to at least partially preserve the organic acid in the catalyst, calcination being understood here to mean a heat treatment at a temperature of 200° C. or higher under air or a gas containing oxygen.

[0135] At the end of the drying step, a rerecovered catalyst is obtained, which will preferably be subjected to an optional activation (sulfiding) step for subsequent use in hydrotreating and / or hydrocracking processes.

[0136] (Restored catalyst) The rerecovered catalyst is composed of a zeolite-free oxide support, an active phase formed from at least one metal from group VIb and at least one metal from group VIII, phosphorus, and an organic acid, and comprises a crystalline phase obtained from at least one metal from group VIII and at least one metal from group VIb, the proportion of which, as determined by X-ray diffraction, is characterized by a ratio of the surface area of the crystalline diffraction peak at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ: less than 0.4.

[0137] The total content of metals from group VIII is between 1% and 15% by weight of oxides of metals from group VIII relative to the total weight of the rerecovered catalyst, preferably between 1.5% and 12% by weight, preferably between 2% and 10% by weight of oxides of metals from group VIII relative to the total weight of the rerecovered catalyst.

[0138] The total content of metals from group VIb is between 5% and 45% by weight of oxides of metals from group VIb relative to the total weight of the rerecovered catalyst, preferably between 8% and 40% by weight of oxides of metals from group VIb relative to the total weight of the rerecovered catalyst, highly preferably between 10% and 30% by weight.

[0139] The molar ratio of the metal from Group VIII to the metal from Group VIb of the recycled catalyst is generally from 0.1 to 0.8, preferably from 0.2 to 0.6.

[0140] The proportion of the crystalline phase obtained from at least one metal from Group VIII and at least one metal from Group VIb, which is determined by X-ray diffraction and characterized by the ratio of the surface area of the diffraction peak of the crystal at 26.6° 2θ to the surface area of the peak characteristic of alumina at 45.7° 2θ, is less than 0.4, preferably less than 0.35, suitably less than 0.3, and even more preferably less than 0.25. The recycled catalyst may not contain a crystalline phase.

[0141] The content rate of one or more organic acids on the recycled catalyst is from 1% by weight to 45% by weight, preferably from 2% by weight to 30% by weight, more preferably from 3% by weight to 25% by weight, based on the total weight of the recycled catalyst.

[0142] The total content rate of phosphorus (introduced by phosphoric acid in step b and possibly already present in the regenerated catalyst) in the recycled catalyst is generally from 0.3% by weight to 25% by weight in terms of the weight of P2O5 based on the total weight of the catalyst, preferably from 0.5% by weight to 20% by weight in terms of the weight of P2O5 based on the total weight of the catalyst, and most preferably from 1% by weight to 15% by weight in terms of the weight of P2O5 based on the total weight of the catalyst.

[0143] (Sulfidation (optional step)) Prior to its use in the reactions of hydrotreating and / or hydrocracking, it is advantageous to convert the recycled catalyst obtained according to the method of the invention into a sulfided catalyst to form its active entity. This activation or sulfidation step is carried out by methods well known to those skilled in the art, preferably under a sulforeduction atmosphere in the presence of hydrogen and hydrogen sulfide.

[0144] At the end of step c) of the recycling method according to the invention, the recycled catalyst is thus advantageously subjected to a sulfidation step without an intermediate calcination step.

[0145] The recovered catalyst is preferably sulfided ex situ or in situ. The sulfiding agent contains H2S gas, elemental sulfur, CS2, thiols, sulfides and / or polysulfides, and is a hydrocarbon fraction having a boiling point of less than 400 °C containing a sulfur-based compound or any other sulfur-containing compound used for the activation of the hydrocarbon feedstock from the viewpoint of sulfiding the catalyst. The sulfur-containing compound is preferably selected from alkyldisulfides such as dimethyldisulfide (DMDS), alkylsulfides such as dimethylsulfide, thiols such as n-butylthiol (or 1-butanethiol), and polysulfide compounds of the tert-nonylpolysulfide 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 added with dimethyldisulfide.

[0146] (Hydrotreating and / or hydrocracking process) Finally, another subject of the present invention resides in the use of the recovered catalyst according to the present invention in a process for the hydrotreating and / or hydrocracking of hydrocarbon fractions.

[0147] The process for the hydrotreating and / or hydrocracking of hydrocarbon fractions can be carried out in one or a plurality of reactors in series of the fixed bed type or the fluidized bed type.

[0148] The process for the hydrotreating and / or hydrocracking of hydrocarbon fractions is carried out in the presence of a recovered catalyst. It can also be carried out in the presence of a mixture of a recovered catalyst and a fresh or regenerated catalyst.

[0149] When a fresh or regenerated catalyst is present, it comprises at least one metal from Group VIII, at least one metal from Group VIb and an oxide support, and optionally phosphorus and / or an organic compound as described above.

[0150] The active phase and support of the fresh or regenerated catalyst may or may not be the same as those of the recovered catalyst.

[0151] The active phase and support of the fresh catalyst may or may not be the same as those of the regenerated catalyst.

[0152] When a process for the hydrotreating and / or hydrocracking of a hydrocarbon fraction is carried out in the presence of a recovered catalyst and a fresh or regenerated catalyst, it can be carried out in a fixed-bed type reactor containing several catalyst beds.

[0153] In this case, according to a first alternative form, the catalyst bed containing the fresh or regenerated catalyst can precede the catalyst bed containing the recovered catalyst in the direction of flow of the feedstock.

[0154] In this case, according to a second alternative form, the catalyst bed containing the recovered catalyst can precede the catalyst bed containing the fresh or regenerated catalyst in the direction of flow of the feedstock.

[0155] In this case, according to a third alternative form, the catalyst bed can contain a mixture of the recovered catalyst and the fresh catalyst and / or the recovered catalyst.

[0156] In these cases, the operating conditions are as described above. They are generally the same in the different catalyst beds, except for the temperature which generally rises in the catalyst bed according to the exothermicity of the hydrodesulfurization reaction.

[0157] A process for the hydrotreating and / or hydrocracking of hydrocarbon fractions is carried out in several reactors in series of the fixed bed type or the fluidized bed type in the presence of a recycled catalyst and a fresh or regenerated catalyst, where one reactor can contain the recycled catalyst while another reactor can contain a fresh or regenerated catalyst, or a mixture of the recycled catalyst with a fresh and / or regenerated catalyst, which can be in any order. It is possible to provide a device for the removal of H2S from the effluent resulting from the first hydrodesulfurization reactor, and then to treat said effluent in a second hydrodesulfurization reactor. In these cases, the operating conditions are as described above and may or may not be the same in different reactors.

[0158] The recycled catalyst, preferably having undergone a pre-sulfiding step, is advantageously used in reactions for the hydrotreating and / or hydrocracking of hydrocarbon feedstocks, such as hydrocarbon fractions resulting from petroleum fractions, fractions from coal, or hydrocarbons, optionally as a mixture, resulting from natural gas, or hydrocarbon fractions resulting from biomass, and more particularly in reactions for the hydrogenation, hydrodenitrogenation, hydrodearomatization, hydrodesulfurization, hydrodeoxygenation, hydrodemetallization or hydroconversion of hydrocarbon feedstocks.

[0159] In these uses, the recycled catalyst, preferably having undergone a pre-sulfiding step, exhibits improved activity compared to catalysts of the prior art. This catalyst can advantageously also be used during the pretreatment of the feedstock by catalytic cracking or hydrocracking, or during the hydrodesulfurization of residual oils or the forced hydrodesulfurization of gas oil (ULSD: ultra-low sulfur diesel).

[0160] The feedstock used in the hydrogenation treatment method is, for example, gasoline, gas oil, vacuum gas oil, atmospheric residue, vacuum residue, atmospheric distillate, vacuum distillate, heavy fuel oil, oil, wax and paraffin, used oil, decanted residue or crude oil, a feedstock originating from a thermal conversion method or a catalytic conversion method, a lignocellulosic feedstock, or more generally a feedstock obtained from biomass, and is used alone or as a mixture. The feedstock to be treated, 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.

[0161] The operating conditions used in the method for carrying out the reaction for the hydrogenation treatment of the above hydrocarbon feedstock are generally as follows: the temperature is preferably 180 °C to 450 °C, preferably 250 °C to 440 °C, the pressure is preferably 0.5 to 30 MPa, preferably 1 to 18 MPa, and the space velocity is preferably 0.1 to 20 h -1 , preferably 0.2 to 5 h -1 -1, and the hydrogen / feedstock ratio is expressed as the volume of hydrogen measured under standard temperature and pressure conditions per volume of the liquid feedstock, and is preferably 50 L / L to 5000 L / L, preferably 80 to 2000 L / L.

[0162] According to the first mode of use, the hydrogenation treatment method is a method for the hydrogenation treatment, particularly hydrodesulfurization (HDS), of a gas oil fraction carried out in the presence of at least one recycled catalyst according to the present invention. The hydrogenation treatment method is targeted at removing sulfur-based compounds present in the gas oil fraction so as to meet effective environmental standards, namely a maximum allowable sulfur content of 10 ppm. Thereby, it is also possible to reduce the content of aromatic compounds and nitrogen in the gas oil fraction to be hydrogenated.

[0163] The gas oil fraction to be hydrogenated contains 0.02 wt% to 5.0 wt% sulfur. It preferably results from straight-run distillation (or straight-run gas oil), a coking unit, a visbreaking unit, a steam cracking unit, a unit for the hydrogenation treatment and / or hydrocracking of heavier feedstocks, and / or a catalytic cracking (fluid catalytic cracking) unit. The gas oil fraction preferably exhibits at least 90% of the compounds having a boiling point of 250°C to 400°C at atmospheric pressure.

[0164] The method for the hydrogenation treatment of the gas oil fraction is carried out under the following operating conditions: the temperature is 200°C to 400°C, preferably 300°C to 380°C; the total pressure is 2 MPa to 10 MPa, more preferably 3 MPa to 8 MPa; the ratio of the volume of hydrogen per volume of hydrocarbon feedstock, expressed as the volume of hydrogen measured under standard temperature and pressure conditions per volume of liquid feedstock, is 100 to 600 liters / liter, more preferably 200 to 400 liters / liter; and the space-time velocity (HSV) is 1 to 10 h -1 , preferably 2 to 8 h -1 . The HSV corresponds to the reciprocal of the contact time expressed in hours and is defined by the ratio of the flow rate by the volume of liquid hydrocarbon feedstock per volume of the catalyst filled in the reaction unit for carrying out the hydrogenation treatment method according to the present invention. The reaction unit for carrying out the method for the hydrogenation treatment of the gas oil fraction is preferably operated as a fixed bed, as a moving bed or as a fluidized bed, preferably as a fixed bed.

[0165] According to the second mode of use, the hydrotreating and / or hydrocracking process is a process for the hydrotreating (in particular, hydrodesulfurization, hydrodenitrogenation, hydrogenation of aromatics) and / or hydrocracking of a vacuum distillate fraction carried out in the presence of at least one recycled catalyst according to the present invention. The hydrotreating and / or hydrocracking process is also known as a hydrocracking pretreatment or hydrocracking process, and optionally, sulfur-based, nitrogen-based or aromatic compounds present in the distillate fraction are removed to perform a pretreatment before conversion in a catalytic cracking or hydroconversion process, or to target the hydrocracking of a distillate fraction that may optionally be pre-treated beforehand.

[0166] A very diverse range of feedstocks can be processed by the above process for the hydrotreating and / or hydrocracking of vacuum distillates. Generally, they contain at least 20% by volume, often at least 80% by volume, of compounds boiling above 340 °C at atmospheric pressure. The feedstock can be, for example, a vacuum distillate, and a feedstock originating from a unit for the extraction of aromatic compounds from a lubricating oil base, or resulting from solvent dewaxing of a lubricating oil base, and / or resulting from decanted oil, or alternatively, the feedstock can be a decanted oil or paraffin resulting from the Fischer-Tropsch process, or any mixture of the above feedstocks. Generally, the T5 boiling point of the feedstock is above 340 °C at atmospheric pressure, more preferably above 370 °C at atmospheric pressure, i.e., the boiling point of 95% of the compounds present in the feedstock is above 340 °C, more preferably above 370 °C. The nitrogen content of the feedstock processed in the process according to the present invention usually exceeds 200 ppm by weight, preferably being 500 - 10,000 ppm by weight. The sulfur content of the feedstock processed in the process according to the present invention is usually from 0.01% to 5.0% by weight. The feedstock can optionally contain metals (e.g., nickel and vanadium). The asphaltene content is generally less than 3000 ppm by weight.

[0167] The recycled catalyst is generally contacted with the above feedstock in the presence of hydrogen, and the temperature at that time is above 200 °C, often 250 °C to 480 °C, preferably 320 °C to 450 °C, and preferably 330 °C to 435 °C. The pressure is above 1 MPa, often 2 to 25 MPa, preferably 3 to 20 MPa, and the space velocity is 0.1 to 20.0 h -1 , preferably 0.1 to 6.0 h -1 , preferably 0.2 to 3.0 h -1 . The amount of hydrogen introduced is such that the ratio of the volume of hydrogen (liters) / the volume of hydrocarbon (liters) is expressed as the volume of hydrogen measured under standard temperature and pressure conditions per volume of the liquid feedstock, and is 80 to 5000 L / L, most often 100 to 2000 L / L. With these operating conditions used in the method according to the invention, generally, the conversion per pass to the product is above 15%, more preferably 20% to 95% at less than 340 °C at atmospheric pressure, and even better at less than 370 °C at atmospheric pressure.

[0168] The method for the hydrotreatment and / or hydrocracking of vacuum distillates using the recycled catalyst according to the invention covers a range of pressures and conversions ranging from mild hydrocracking to high-pressure hydrocracking. Mild hydrocracking is understood to mean hydrocracking that results in a moderate, generally less than 40% conversion and operates at low pressure, generally 2 MPa to 6 MPa.

[0169] The recycled catalyst according to the invention can be used alone, in a single or several fixed-bed catalyst beds in one or more reactors, in a "one-stage" hydrocracking scheme, with or without liquid recycle of the unconverted fraction, or in a "two-stage" hydrocracking scheme, optionally in combination with a hydrotreating catalyst located upstream of the recycled catalyst.

[0170] According to the third mode of use, the hydrogenation treatment and / or hydrocracking process is advantageously used as a pretreatment in a fluid catalytic cracking (or FCC: fluid catalytic cracking) process. The operating conditions of the pretreatment regarding the ranges of temperature, pressure, hydrogen recycle ratio, and space velocity are generally the same as those described above for the process for the hydrogenation treatment and / or hydrocracking of vacuum distillates. The FCC process can be carried out under cracking conditions appropriate in conventional processes known to those skilled in the art for the purpose of producing hydrocarbon products of lower molecular weight. A general description of catalytic cracking can be found, for example, in Ullmann's Encyclopedia of Industrial Chemistry, Volume A18, 1991, pages 61 to 64.

[0171] According to the fourth mode of use, the hydrogenation treatment and / or hydrocracking process according to the invention is a process for the hydrogenation treatment (in particular hydrodesulfurization) of a gasoline fraction in the presence of at least one recycled catalyst according to the invention.

[0172] Unlike other hydrogenation processes, the hydrogenation treatment of gasoline (in particular hydrodesulfurization) must be able to cope with two opposing constraints: providing extreme hydrodesulfurization of gasoline and limiting the hydrogenation of unsaturated compounds present in order to limit the loss in octane number.

[0173] The feedstock is generally a hydrocarbon fraction having a boiling range of 30°C to 260°C. Preferably, this hydrocarbon fraction is a gasoline-type fraction. Most preferably, the gasoline fraction is, for example, an olefinic gasoline fraction resulting from a catalytic cracking (fluid catalytic cracking) unit.

[0174] The hydrogenation treatment method comprises contacting a hydrocarbon fraction with a recycled catalyst and hydrogen under the following conditions: the temperature is 200°C to 400°C, preferably 230°C to 330°C, the total pressure is 1 to 3 MPa, preferably 1.5 to 2.5 MPa, and the space velocity (HSV), which is defined as the flow rate by volume of the feedstock supplied relative to the volume of the catalyst, is 1 to 10 h -1 , preferably 2 to 6 h -1 and the hydrogen / gasoline feedstock ratio is 100 to 600 SL / L, preferably 200 to 400 SL / L.

[0175] The method for the hydrogenation treatment of gasoline can be carried out in a fixed-bed type or fluidized-bed type reactor, one or a plurality of reactors in series. If the method is carried out by at least two reactors in series, it is possible to provide a device for the removal of H2S from the effluent resulting from the first hydrodesulfurization reactor, and then to treat the said effluent in the second hydrodesulfurization reactor.

[0176] The following examples demonstrate a significant increase in activity on the recycled catalyst prepared according to the method of the present invention in comparison with prior art catalysts.

[0177] (Example) (Example 1: Obtaining of regenerated catalyst A1) The hydrogenation catalyst was used on a unit for the hydrogenation treatment of gas oil in an oil refinery for 2 years. The used catalyst contains 10 wt% carbon and 9 wt sulfur. After the deoiling stage, the catalyst is subjected to regeneration at 480°C in an oxidizing atmosphere. Catalyst A1 is obtained. This contains nickel, molybdenum and phosphorus, and its content is, as oxide equivalents, 4.5% NiO, 20.3% MoO3 and 4.4% P2O5, and is supported on gamma alumina. The water retention of catalyst A1 is 0.4 cc / g. The carbon and sulfur contents of this catalyst are 0.03 wt% and 0.2 wt% respectively. The ratio of the surface area of the diffraction peak NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) is 0.85.

[0178] (Example 2: Obtaining of regenerated catalysts A2, A3, A4, A5, and A6) The same used and deoiled catalyst from Example 1 is regenerated under an oxidizing atmosphere at different temperatures: 450 °C, 400 °C, 380 °C, 360 °C, and 340 °C, respectively, to obtain regenerated catalysts A2, A3, A4, A5, and A6 with a water retention of 0.4 cc / g each.

[0179] The carbon and sulfur contents of catalyst A2 are 0.05 wt% and 0.3 wt%, respectively. The ratio of the surface area of the diffraction peak NiMoO4(26.6° 2θ) / γ - Al2O3(45.7° 2θ) is 0.78.

[0180] The carbon and sulfur contents of catalyst A3 are 0.1 wt% and 0.6 wt%, respectively. The ratio of the surface area of the diffraction peak NiMoO4(26.6° 2θ) / γ - Al2O3(45.7° 2θ) is 0.47.

[0181] The carbon and sulfur contents of catalyst A4 are 0.3 wt% and 0.7 wt%, respectively. The ratio of the surface area of the diffraction peak NiMoO4(26.6° 2θ) / γ - Al2O3(45.7° 2θ) is 0.23.

[0182] The carbon and sulfur contents of catalyst A5 are 0.5 wt% and 0.8 wt%, respectively. The ratio of the area NiMoO4 / alumina is 0.11.

[0183] The carbon and sulfur contents of catalyst A6 are 1.8 wt% and 1.4 wt%, respectively. The ratio of the surface area of the diffraction peak NiMoO4(26.6° 2θ) / γ - Al2O3(45.7° 2θ) is 0.10.

[0184] (Example 3: Obtaining of catalysts B1 and B2 not conforming to the present invention) Catalyst B1 is prepared from the regenerated catalyst A1. A solution containing phosphoric acid and gluconic acid is dry-impregnated on catalyst A1, and on the recovered catalyst, a P / Mo molar ratio of 0.8 and a gluconic acid / Mo molar ratio of 0.8 are obtained. After aging for 3 hours, the catalyst is dried at 120 °C for 2 hours. The ratio of the surface areas of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) is 0.57. Catalyst B2 is obtained in the same steps starting from the regenerated catalyst A2. The ratio of the surface areas of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) is 0.45.

[0185] (Example 4: Obtaining Catalysts B3, B4, and B5 Consistent with the Present Invention) Catalyst B3 is prepared from the regenerated catalyst A3. A solution containing phosphoric acid and gluconic acid is dry-impregnated on catalyst A3, and on the recovered catalyst, a P / Mo molar ratio of 0.8 and a gluconic acid / Mo molar ratio of 0.8 are obtained. After aging for 3 hours, the catalyst is dried at 120 °C for 2 hours. The ratio of the surface areas of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) is 0.20. Catalysts B4 and B5 are obtained in the same steps but starting from the regenerated catalysts A4 and A5, respectively. The ratios of the surface areas of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) are 0.13 and 0.06, respectively.

[0186] (Example 5: Obtaining Catalyst B6 Inconsistent with the Present Invention) Catalyst B6 is prepared from the regenerated catalyst A6. A solution containing phosphoric acid and gluconic acid is dry-impregnated on catalyst A6, and on the recovered catalyst, a P / Mo molar ratio of 0.8 and a gluconic acid / Mo molar ratio of 0.8 are obtained. After aging for 3 hours, the catalyst is dried at 120 °C for 2 hours. The ratio of the surface areas of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) is 0.05.

[0187]

Table 1

[0188] (Example 6: Evaluation of the hydrogenation (HOA) of aromatic compounds in gas oil over catalysts B1, B2 and B6 (not in accordance with the present invention) and B3, B4 and B5 (in accordance with the present invention)) Catalysts B1, B2 and B6 (not in accordance with the present invention) and B3, B4 and B5 (in accordance with the present invention) were tested in the HOA of gas oil. The regenerated catalyst B1 was used as a reference.

[0189] The feedstock is a mixture of 30% by volume of gas oil resulting from atmospheric distillation (also called straight-run distillation) and 70% by volume of light gas oil resulting from a catalytic cracking unit (also known as light cycle oil LCO). The characteristics of the test feedstock used are as follows: density at 15 °C = 0.8994 g / cm 3 (NF EN ISO12185), refractive index at 20 °C = 1.5143 (ASTM D1218-12), sulfur content = 0.38 wt%, nitrogen content = 0.05 wt%. · Simulated distillation (ASTM D2887): - IP: 133 °C - 10%: 223 °C - 50%: 285 °C - 90%: 357 °C - FP: 419 °C

[0190] The tests were carried out in an isothermal pilot reactor with a cross-flow fixed bed, and the fluid was circulated from the bottom upwards.

[0191] Pre-in-situ sulfidation of the catalyst was carried out at 350 °C in a reactor under pressure with a straight-run (atmospheric) distillation gas oil feedstock (density at 15 °C = 0.8491 g / cm 3 (NF EN ISO12185) and an initial sulfur content = 0.42 wt%) to which 2 wt% of dimethyldisulfide was added.

[0192] The test for the hydrogenation of aromatic compounds was carried out under the following operating conditions: total pressure 8 MPa, catalyst volume 4 cm 3, temperature 330 °C, hydrogen flow rate 3.0 L / h and feedstock flow rate 4.5 cm 3 / h.

[0193] Analyze the characteristics of the effluent: density at 15 °C (NF EN ISO12185), refractive index at 20 °C (ASTM D1218-12), simulated distillation (ASTM D2887), sulfur content and nitrogen content. Calculate the residual content of aromatic carbon by the n-d-M method (ASTM D3238). Calculate the degree of hydrogenation of the aromatic compound as the ratio of the aromatic carbon content of the effluent to the content of the test feedstock. The catalytic performance quality of the tested catalysts is shown in Table 1. They are expressed as the relative volume activity (RVA) with respect to the reference catalyst B1, assuming 1.7 order for the relevant reactions.

[0194] Catalysts B3, B4 and B5 according to the present invention exhibit the best activity exceeding RVA 110. They are prepared from regenerated catalysts that simultaneously show a carbon and sulfur content of 0.1 wt% to 0.5 wt% and 0.3 wt% to 0.8 wt% respectively, and a ratio of the surface area of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) of less than 0.6 by controlled regeneration. By the re-recovery step, it is then possible to partially dissolve the NiMoO4 crystal phase and redisperse the molybdenum-based and nickel-based entities, thus obtaining a re-recovered catalyst according to the present invention showing a ratio of the surface area of the diffraction peaks NiMoO4(26.6° 2θ) / γ-Al2O3(45.7° 2θ) of less than 0.4.

Claims

1. A method for restoring at least partially used catalysts obtained from hydrogenation and / or hydrocracking methods, wherein the at least partially used catalyst is obtained from a fresh catalyst containing at least one metal from Group VIII, at least one metal from Group VIB, an oxide support that does not contain zeolite, and optionally phosphorus, and comprising the following steps: a) Regenerating a catalyst that is at least partially used in an oxygen-containing gas stream at a temperature between 360°C and less than 420°C; obtaining a regenerated catalyst; the catalyst containing carbon in a content of 0.1% to 0.5% by weight and sulfur in a content of 0.3% to 0.8% by weight, the proportion of crystalline phases obtained from at least one metal from Group VIII and at least one metal from Group VIB, determined by X-ray diffraction and characterized by the ratio of the surface area of ​​the diffraction peak of the crystal at 26.6°²θ to the surface area of ​​the peak characteristic of alumina at 45.7°²θ, is less than 0.

6. b) Next, the regenerated catalyst is mixed with water, phosphoric acid, and each acidity constant pK ａ The step of bringing it into contact with an aqueous solution consisting of an organic acid greater than 1.5, c) The drying step is carried out at a temperature below 200°C, but it is not subsequently calcined; a re-recovered catalyst is obtained.

2. The method according to claim 1, wherein the temperature in step a) is 380°C to 410°C.

3. The method according to claim 1, wherein the proportion of crystalline phases obtained from at least one metal from Group VIII and at least one metal from Group VIb is determined by X-ray diffraction in step a) and characterized by the ratio of the surface area of ​​the diffraction peak of the crystal at 26.6°2θ to the surface area of ​​the peak characteristic of alumina at 45.7°2θ, and is less than 0.

50.

4. The method according to claim 1, wherein the organic acid used in step b) is selected from gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, lactic acid, pyruvic acid, ascorbic acid, or succinic acid.

5. The organic acids used in step b) have their respective acidity constants pK ａ The method according to claim 1, wherein the organic acid is greater than 3.

5.

6. The method according to claim 1, wherein the organic acid used in step b) is selected from gluconic acid, γ-ketovaleric acid, lactic acid, pyruvic acid, ascorbic acid, or succinic acid.

7. The method according to claim 1, wherein the molar ratio of the added organic acid per one or more metals from Group VIb present in the regenerated catalyst is 0.01 to 5 mol / mol.

8. The method according to claim 1, wherein the molar ratio of phosphorus added per metal from Group VIb already present in the regenerated catalyst is 0.01 to 5 mol / mol.

9. The method according to claim 1, wherein the content of metals from Group VIb of the fresh catalyst is 1% to 40% by weight in terms of the weight of oxides of the metals from Group VIb relative to the weight of the catalyst, and the total content of metals from Group VIII is 1% to 10% by weight in terms of the weight of oxides of the metals from Group VIII relative to the weight of the catalyst.

10. Fresh catalysts contain phosphorus, and the total phosphorus content is P relative to the total weight of the catalyst. ２ O ５ The method according to claim 1, expressed as such, and in an amount of 0.1% to 20% by weight.

11. The method according to claim 1, wherein the oxide support that does not contain zeolite is selected from alumina, silica, silica-alumina, or titanium or magnesium oxide used alone or in a mixture with alumina or silica-alumina.

12. The method according to claim 1, wherein the proportion of crystalline phases obtained from at least one metal from Group VIII and at least one metal from Group VIB of the recovered catalyst obtained from step c) is determined by X-ray diffraction and characterized by the ratio of the surface area of ​​the diffraction peak of the crystal at 26.6°2θ to the surface area of ​​the peak characteristic of alumina at 45.7°2θ is less than 0.

4.

13. The method according to claim 1, wherein, prior to regeneration step a), a de-oiling step is performed, the step comprising contacting at least partially used catalyst obtained from a hydrogenation treatment and / or hydrocracking method with a flow of inert gas at a temperature of 300°C to 400°C.

14. The method according to claim 1, wherein the re-recovered catalyst is subjected to the sulfidation step after step c).

15. Use of a catalyst obtained by any one of claims 1 to 14 in a method for the hydrogenation and / or hydrocracking of hydrocarbon fractions.