FR3075663A1

FR3075663A1 - HYDROPROCESSING AND / OR HYDROCRACKING CATALYST PREPARED BY PARTICLE DISSOLUTION COMPRISING GROUP VIII METAL AS A METALLIC FORM

Info

Publication number: FR3075663A1
Application number: FR1762948A
Authority: FR
Inventors: Audrey Bonduelle-Skrzypczak; David Pasquier; Emmanuelle TRELA-BAUDOT
Original assignee: IFP Energies Nouvelles IFPEN
Current assignee: IFP Energies Nouvelles IFPEN
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2019-06-28

Abstract

Procédé de préparation d'un catalyseur d'hydrotraitement et/ou d'hydrocraquage comprenant une phase active à base d'un métal du groupe VIB et d'un métal du groupe VIII, et un support poreux, lequel procédé comprend au moins les étapes suivantes : a) une étape au cours de laquelle on forme des particules d'au moins un précurseur catalytique comprenant au moins un métal du groupe VIII au moins partiellement sous forme métallique sur le support poreux ; b) une étape de mise en contact du précurseur de catalyseur obtenu à l'étape a) avec une solution aqueuse ou organique comprenant au moins un précurseur catalytique comprenant au moins un métal du groupe VIB; c) optionnellement, une étape de maturation du précurseur de catalyseur obtenu à l'étape b) pendant 30 minutes à 24 heures ; d) une étape de séchage du précurseur de catalyseur obtenu à l'étape b) ou c) à une température inférieure à 250 °C.A process for preparing a hydrotreating and / or hydrocracking catalyst comprising an active phase based on a Group VIB metal and a Group VIII metal, and a porous support, which process comprises at least the steps following: a) a step in which particles of at least one catalytic precursor comprising at least one metal of group VIII at least partially in metallic form on the porous support are formed; b) a step of contacting the catalyst precursor obtained in step a) with an aqueous or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal; c) optionally, a step of maturing the catalyst precursor obtained in step b) for 30 minutes to 24 hours; d) a step of drying the catalyst precursor obtained in step b) or c) at a temperature below 250 ° C.

Description

Field of the invention

The present invention relates to a method for preparing a hydrotreating and / or hydrocracking catalyst comprising an active phase comprising at least one Group VI metal and at least one Group VIII metal obtained by chemical reduction.

The present invention also relates to the use of said catalyst in the hydrotreatment and / or hydrocracking processes. State of the art

The composition and use of the hydrotreating and hydrocracking catalysts of hydrocarbon feedstocks are respectively well described in the literature: "Catalysis by transition metal sulphides, From Molecular Theory to Industrial Application", 2013, H. Toulhouat, P. Raybaud and "Hydrocracking Science and Technology", 1996, J. Scherzer, AJ Gruia, Marcel Dekker Inc.

Thus, the catalysts used in the refining processes, whether they are intended for hydrotreatment or hydrocracking reactions, are generally characterized by a hydro-dehydrogenating function provided by the presence of an active phase based on at least a Group VIB metal and optionally at least one Group VIII metal of the periodic table of the elements. The most common formulations are cobalt-molybdenum (CoMo), nickel-molybdenum (NiMo) and nickel-tungsten (NiW). These catalysts may be in mass form (valid specifically for hydrotreatment catalysts) or in the supported state, thus involving a porous support of a different nature. In the latter case, the porous support is generally an amorphous or poorly crystallized oxide (alumina, aluminosilicate, etc.), optionally associated with a zeolite material or not. After preparation, at least one Group VIB metal and optionally at least one Group VIII metal constituent (s) of said catalysts is often in an oxidized form. The active and stable form for the hydrocracking (HCK) and hydrotreating (HDT) processes being the sulfurized form, these catalysts must undergo a sulphurization step. This can be carried out in the unit of the associated process (this is called in-situ sulphurization) or prior to the loading of the catalyst into the unit (this is called ex situ sulphurization).

It is generally known to a person skilled in the art that good catalytic performances in the fields of application mentioned above are a function of: 1) the nature of the hydrocarbon feed to be treated, 2) the process employed, 3) conditions selected operating procedures and 4) the catalyst used. In the latter case, it is also accepted that a catalyst having a high catalytic potential is characterized by: 1) an optimized hydro-dehydrogenating function (associated active phase perfectly dispersed on the support surface and having a high active phase content) and 2) in the particular case of processes involving HCK reactions, by a good balance between said hydro-dehydrogenating function and the cracking function. Note also that, ideally, whatever the nature of the hydrocarbon feedstock to be treated, the catalyst must have an accessibility of the active sites vis-à-vis the reagents while developing a high active surface, which can lead to specific constraints in terms of structure and texture, specific to the constituent oxide support of said catalysts.

The usual methods leading to the formation of the hydro-dehydrogenating phase of the hydrotreatment and hydrocracking catalysts consist of a precursor deposit (s) comprising at least one Group VIB metal and optionally at least one Group VIII metal on a oxide support by the so-called "dry impregnation" technique or by the so-called "excess impregnation" technique, followed by the maturation, drying and possibly calcination steps leading to the formation of the oxidized form of said metal (s) employee (s). Then comes the final stage of sulfuration generating the hydro-dehydrogenating active phase, as mentioned above.

It appears interesting to find ways of preparing the hydrotreatment catalysts, to obtain new catalysts with improved performance. The prior art shows that the researchers have turned to several methods including the use of various and varied polyoxometalates, the addition of doping elements, the addition of organic molecules with various and varied properties (solvation, complexation .. .) or, but to a lesser extent, the use of reducing compounds in the preparation.

US Pat. No. 5,332,709 thus proposes to stabilize aqueous solutions of compounds of group VIB and VIII elements by the simultaneous use of an inorganic phosphorus acid such as phosphoric acid and a reducing compound. The solutions contain a high proportion of the phosphoric compound, usually from 5 to 15 or 20% by weight of the phosphorus acid.

Similarly, US Pat. No. 5,338,717 proposes to reduce a group VIB metal compound such as phosphomolybdic acid by the use of a reducing agent, after the Group VIB metal compound has been deposited on a support and the impregnated support was dried. The resulting catalyst, which also contains a Group VIII compound, is indicated as useful as a hydrotreatment catalyst.

The patent application FR 2,749,778 describes the advantage of heteropolyanions (HPA) of general formula MxAB | 2O40, in which M is cobalt or nickel, A is phosphorus, silicon or boron and B is molybdenum or tungsten, x takes the value of 2 or more if A is phosphorus, 2.5 or more if A is silicon and 3 or more if A is boron. These structures have the advantage over the structures disclosed in US Pat. No. 2,547,380 of attaining higher atomic ratios (Group VIII element / Group VIB element) and thus lead to more efficient catalysts. This increase in the ratio is obtained thanks to the presence of at least a portion of the molybdenum or tungsten at a valence lower than its normal value of six, as resulting from the composition, for example, phosphomolybdic acid, phosphotungstic, silicomolybdic or silicotungstic. The reduction of the compounds based on Mo or W can be carried out either from the addition of a reducing agent, such as hydrazine, or from reduced metal (Co, Ni or Fe metal to the degree of oxidation 0). The catalytic activities of the catalysts thus prepared are thus superior in HDS of thiophene to those of the references prepared and described in the patent. The preparation is more fully described in the article by Griboval et al. (Studies in Surface Science and Catalysis 106 (1997) 181-194) and the catalytic tests in a second article by Griboval et al. (Catalysis Today 45 (1998) 277-283). The prior art discloses hydrotreatment catalyst preparations involving the reduction of precursors comprising at least one Group VIB metal by reducing compounds, and allowing the improvement of the catalytic performance.

The Applicant has surprisingly found that the reduction of a solution comprising at least one catalytic precursor comprising at least one Group VIB metal within the porous support, by means of particles comprising at least one Group VIII metal at the degree of Oxidation 0 makes it possible to increase the catalytic performances of the catalysts prepared by this method, by avoiding the introduction of any additional reducing chemical agent that is potentially deleterious to catalytic activity.

An object of the present invention relates to a process for preparing a hydrotreatment and / or hydrocracking catalyst obtained by a chemical reduction method, using reduced precursors, improving the catalytic performance of said catalysts, compared with catalysts prepared from unreduced precursors.

Objects of the invention

The present invention firstly relates to a process for preparing a hydrotreatment and / or hydrocracking catalyst comprising at least one active phase based on a Group VIB metal and a Group VIII metal, and a porous support comprising at least one refractory oxide, which process comprises at least the following steps: a) a step during which particles of at least one catalytic precursor comprising at least one group VIII metal are formed at least partially in the form of metallic on the porous support; b) a step of contacting the catalyst precursor obtained in step a) with an aqueous and / or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal; c) optionally, a step of maturing the catalyst precursor obtained in step b) for 30 minutes to 24 hours; d) a step of drying the catalyst precursor obtained in step b) or c) at a temperature below 250 ° C, without further calcination, to obtain a dried catalyst.

Preferably, step a) comprises at least the following sub-steps: i) a step of contacting an aqueous and / or organic solution comprising the at least one catalytic precursor comprising at least one metal of group VIII with the porous support, said contacting being carried out by impregnation, dry or in excess, or by chemical vapor deposition; ii) optionally, a ripening step for 30 minutes to 24 hours if step i) is an impregnation step; iii) optionally, a drying step at a temperature below 250 ° C if step i) is an impregnation; iv) optionally, a step of reducing the catalyst precursor comprising at least one Group VIII metal obtained in step i) or iii) if at least one Group VIII metal is not in metallic form.

Advantageously, the step i) of contacting is carried out by dry impregnation.

Preferably, step iv) is carried out in the presence of a reducing gas at a temperature between 120 and 500 ° C, for a period of between 2 and 40 hours.

Advantageously, the group VIII metal is chosen from nickel, cobalt and iron.

Preferably, step i) is carried out by impregnation of a colloidal solution of the at least one catalytic precursor comprising at least one metal of group VIII, in oxidized form.

Preferably, step i) is carried out by impregnation of a colloidal solution of the at least one catalytic precursor comprising at least one metal of group VIII, in reduced form.

Advantageously, said catalytic precursor comprising at least one metal of group VIB is chosen from polyoxometalates corresponding to the formula (HhXxMmOy) q "in which H is hydrogen, X is an element chosen from phosphorus (P), silicon ( Si), boron (B), nickel (Ni) and cobalt (Co), M is one or more metal (s) selected from molybdenum (Mo), tungsten (W), nickel ( Ni) and cobalt (Co), O being oxygen, h being an integer from 0 to 12, x being an integer from 0 to 4, m being an integer of 5, 6, 7, 8, 9 , 10, 11, 12 and 18, where y is an integer from 17 to 72 and q is an integer from 1 to 20, with the proviso that M is not a nickel atom or a cobalt atom alone. particular embodiment x = 0.

Advantageously, the m atoms M are either only molybdenum (Mo) atoms, or only tungsten atoms (W), or a mixture of molybdenum (Mo) and cobalt (Co) atoms, or a mixture of molybdenum (Mo) and nickel (Ni) atoms, a mixture of tungsten (W) and nickel (Ni) atoms.

Advantageously, the m atoms M are either a mixture of nickel (Ni), molybdenum (Mo) and tungsten (W) atoms, or a mixture of cobalt (Co), molybdenum (Mo) and tungsten (W).

Advantageously, a c) maturation step is carried out at a temperature of between 17 and 50 ° C. for 30 minutes to 24 hours in an O 2 -free atmosphere.

Advantageously, the drying step d) is carried out at a temperature of less than or equal to 120 ° C., in an atmosphere free of Q.

Advantageously, the porous support comprising at least one refractory oxide is chosen from transition aluminas, doped alumina, preferably phosphorus, boron and / or fluorine, silicalite and silicas, aluminosilicates, preferably amorphous or partially crystallized non-zeolitic crystalline molecular sieves such as silicoaluminophosphates, aluminophosphates, ferrosilicates, titanium silicoaluminates, borosilicates, chromosilicates and transition metal aluminophosphates, alone or as a mixture.

Another object according to the invention relates to a process for hydrotreating or hydrocracking a hydrocarbon feedstock in the presence of hydrogen and of a catalyst obtained by the process according to any one of Claims 1 to 14 implemented in a temperature between 180 and 450 ° C, a pressure of between 0.5 and 30 MPa, a hourly volume velocity (VVH) between 0.1 and 20 h "1, and wherein the amount of hydrogen introduced is such that the volumetric ratio of hydrogen per liter of hydrocarbon is between 50 and 5000 Nl / l.

Description of the invention Definitions

In the following, groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IUPAC classification.

Description

The Applicant has discovered that the reduction of the catalytic precursors comprising at least one Group VIB metal increases the catalytic performance of the catalysts obtained. Furthermore, the preparation process according to the invention makes it possible to carry out the step of reducing the catalytic precursor comprising at least one Group VIB metal directly within the porous support by means of the catalytic precursor comprising at least one Group VIII metal. at least partially in metallic form (at the oxidation degree 0), which considerably improves the dispersion of the species and therefore the dispersion of the active phase after activation. The preparation process according to the invention thus makes it possible to overcome the introduction of any additional reducing chemical agent (potentially toxic such as the hydrazine generally used for the reduction of catalytic precursors comprising at least one Group VIB metal) and or potentially deleterious to catalytic activity.

The present invention relates to a process for preparing hydrotreatment and / or hydrocracking catalysts, comprising an active phase comprising at least one Group VIB metal and at least one Group VIII metal, and a porous support, said preparation method comprising at least one step in which an aqueous and / or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal is deposited on said porous support comprising catalytic precursors comprising at least one Group VIII metal at the oxidation degree 0.

The present invention also relates to the use of said catalyst in the hydrotreatment and / or hydrocracking processes.

The method for preparing the hydrotreatment and / or hydrocracking catalyst according to the invention comprises at least the following steps: a) at least one catalytic precursor comprising at least one metal of group VIII at least partially in metallic form on the porous support; b) at least one step of contacting the catalytic precursor obtained in step a) with an aqueous or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal; c) optionally, at least one step of maturing the catalyst precursor obtained in step b) for 30 minutes to 24 hours; d) a step of drying the catalytic precursor obtained in step b) or c) at a temperature below 250 ° C, preferably below 180 ° C, without subsequent calcination, to obtain a dried catalyst.

According to the invention, calcination is understood to mean any heat treatment carried out at a temperature greater than or equal to 250 ° C., in an atmosphere comprising O2.

Preferably, the dried catalyst obtained at the end of step d) undergoes a step e) of sulfurization to obtain a sulphurized catalyst.

Furthermore, any organic additive or other doping element can be introduced at any of the steps mentioned above or in an additional step. In particular, said organic compound is advantageously deposited by impregnation, before impregnation of the metal precursors, co-impregnation with the metal precursors or post-impregnation after impregnation of the metal precursors.

Said organic compound may be chosen from all the organic compounds known to those skilled in the art, chelating agents, non-chelating agents, reducing agents, non-reducing agents. It may also be chosen from optionally etherified mono-, di- or polyalcohols, carboxylic acids, sugars, non-cyclic mono, di or polysaccharides such as glucose, fructose, maltose, lactose or sucrose, esters, ethers, crown ethers, cyclodextrins and compounds containing sulfur or nitrogen such as nitriloacetic acid, ethylenediaminetetraacetic acid, or diethylenetriamine alone or in admixture. Said doping element may be chosen from precursors of B, P or Si.

Precursors comprising at least one Group VIB metal:

Precursors comprising at least one group VIB metal may be chosen from all the precursors of group VIB elements known to those skilled in the art. They may be chosen from polyoxometalates (POM) or precursor salts of group VIB elements, such as molybdates, thiomolybdates, tungstates or thiotungstates. They can be chosen from organic or inorganic precursors, such as MoCI5 or WCI4 or WCI6 or the alkoxides of Mo or W, for example Mo (OEt) 5 or W (OEt) 5.

In the context of the present invention, the term polyoxometalates (POM) as being the compounds corresponding to the formula (HhXxMmOy) q "in which H is hydrogen, X is an element chosen from phosphorus (P), silicon (Si), boron (B), nickel (Ni) and cobalt (Co), said element being taken alone, M is one or more element (s) chosen from molybdenum (Mo), tungsten (W), nickel (Ni) and cobalt (Co), where O is oxygen, h being an integer from 0 to 12, x being an integer from 0 to 4, m being an integer of 5, 6, 7, 8, 9, 10, 11, 12 and 18, where y is an integer from 17 to 72 and q is an integer from 1 to 20. The element M can not be a nickel atom or a cobalt atom alone.

The polyoxometalates defined according to the invention include two families of compounds, isopolyanions and heteropolyanions. These two families of compounds are defined in the article Heteropoly and Isopoly Oxometallates, Pope, Ed Springer-Verlag, 1983.

The isopolyanions which can be used in the present invention are polyoxometallates of general formula (HhXxMmOy) q "in which x = 0, the other elements having the above-mentioned meaning.

Preferably, the m atoms M of said isopolyanions are either only molybdenum atoms, or only tungsten atoms, or a mixture of molybdenum and cobalt atoms, or a mixture of molybdenum and nickel atoms, or one of a mixture of tungsten and cobalt atoms, a mixture of tungsten and nickel atoms.

The m atoms M of said isopolyanions may also be either a mixture of nickel, molybdenum and tungsten atoms or a mixture of cobalt, molybdenum and tungsten atoms.

Preferably, in the case where the element M is molybdenum (Mo), m is equal to 7. Similarly, in the case where the element M is tungsten (W), m is equal to 12 .

The isopolyanons Mo70246 "and H2W12O406" are advantageously used as active phase precursors in the context of the invention.

The heteropolyanions which can be used in the present invention are polyoxometalates of formula (HhXxMmOy) q "in which x = 1, 2, 3 or 4, the other elements having the above-mentioned meaning.

The heteropolyanions generally have a structure in which the element X is the "central" atom and the element M is a metal atom that is practically systematically in octahedral coordination with X ψ M.

Preferably, the m atoms M are either only molybdenum atoms, or only tungsten atoms, or a mixture of molybdenum and cobalt atoms, or a mixture of molybdenum and nickel atoms, or a mixture of tungsten and molybdenum atoms, a mixture of tungsten and cobalt atoms, or a mixture of tungsten and nickel atoms. Preferably, the m atoms M are either only molybdenum atoms, or a mixture of molybdenum and cobalt atoms, or a mixture of molybdenum and nickel atoms. Preferably, the m atoms M can not be only nickel atoms, or only cobalt atoms.

Preferably, the element X is at least one phosphorus atom or one Si atom.

Heteropolyanions are negatively charged polyoxometallate species. To compensate for these negative charges, it is necessary to introduce counter ions and more particularly cations. These cations may advantageously be H + protons, or any other cation of NH 4 + type or metal cations and in particular metal cations of Group VIII metals.

In the case where the counterions are protons, the molecular structure comprising the heteropolyanion and at least one proton constitutes a heteropolyacid. The heteropolyacids which can be used as active phase precursors in the present invention can be, for example, phosphomolybdic acid (3H +, PMo12O403 ") or phosphotungstic acid (3H +, PW12O403j.

In the case where the counter-ions are not protons, we then speak of heteropolyanion salt to designate this molecular structure. It is then advantageous to take advantage of the association within the same molecular structure, via the use of a heteropolyanion salt, of the metal M and its promoter, ie of the cobalt element and / or or the nickel element which can either be in position X within the structure of the heteropolyanion, or in partial substitution of at least one M atom of molybdenum and / or tungsten within the structure of the heteropolyanion , in the counter-ion position.

Preferably, the polyoxometalates used according to the invention are the compounds corresponding to the formula (HhXxMmOy) q "in which H is hydrogen, X is a member chosen from phosphorus (P), silicon (Si), boron (B), nickel (Ni) and cobalt (Co), said element being taken alone, M is one or more element (s) chosen from molybdenum (Mo), tungsten (W), nickel (Ni) and cobalt (Co), O being oxygen, h being an integer between 0 and 6, x being an integer possibly equal to 0, 1 or 2, m being an integer equal to 5, 6 , 7, 9, 10, 11 and 12, where y is an integer of 17 to 48 and q is an integer of 3 to 12.

More preferably, the polyoxometalates used according to the invention are the compounds corresponding to the formula (HhXxMmOy) q "in which h is an integer equal to 0, 1, 4 or 6, x being an integer equal to 0, 1 or 2, m being an integer of 5, 6, 10, 11 or 12, y being an integer of 23, 24, 38, or 40 and q being an integer of 3, 4, 6 and 7, H, X, M and O having the meaning mentioned above.

The preferred polyoxometalates used according to the invention are advantageously chosen from polyoxometalates of formula PMO2O403-, HPCoMonO406-, HPNiMonO406-, P2Mo50236-, Co2M10O38H46-, CoMo6024H64-, taken alone or as a mixture.

Preferred polyoxometalates which can advantageously be used in the process according to the invention are so-called Anderson heteropolyanions of the general formula XM6O24q "for which the ratio m / x is equal to 6 and in which the elements X and M and the charge q The element X is therefore an element selected from phosphorus (P), silicon (Si), boron (B), nickel (Ni) and cobalt (Co), said element being taken alone. , M is one or more element (s) chosen from molybdenum (Mo), tungsten (W), nickel (Ni) and cobalt (Co), and q is an integer between 1 and 20 and preferably between 3 and 12.

The particular structure of said so-called Anderson heteropolyanions is described in the article Nature, 1937, 150, 850. The structure of said so-called Anderson heteropolyanions comprises 7 octahedra located in the same plane and interconnected by the edges: of the 7 octahedra, 6 octahedra surround the central octahedron containing element X.

Anderson heteropolyanions containing within their structure cobalt and molybdenum or nickel and molybdenum are preferred. Anderson heteropolyanions of formula CoMo6024H63 "and NiMo6024H64" are particularly preferred. According to the formula, in these Anderson heteropolyanions, the cobalt and nickel atoms are respectively the heteroelements X of the structure.

In the case where the Anderson heteropolyanion contains within its structure cobalt and molybdenum, a mixture of the two monomeric forms of formula CoMo6024H63 "and dimeric formula Co2Mo10O38H46" said heteropolyanion, the two forms being in equilibrium, can advantageously to be used. In the case where the Anderson heteropolyanion contains within its structure cobalt and molybdenum, said Anderson heteropolyanion is preferably dimeric of formula Co2Mo10O38H46 ".

In the case where the Anderson heteropolyanion contains within its structure nickel and molybdenum, a mixture of the two monomeric forms of formula NiMo6024H64 "and dimeric formula Ni2Mo10038H48" said heteropolyanion, the two forms being in equilibrium, can advantageously to be used. In the case where the Anderson heteropolyanion contains within its structure nickel and molybdenum, said Anderson heteropolyanion is preferably monomeric of formula NiMo6024H64 ".

Salts of Anderson heteropolyanions can also be advantageously used as active phase precursors according to the invention. Said Anderson heteropolyanion salts are advantageously chosen from the cobalt or nickel salts of the 6-molybdocobaltate monomeric ion respectively of formula CoMo6024H63 ", 3/2 Co2 + or CoMo6024H63", 3/2 Ni2 + having an atomic ratio of said (Co and / or Ni) / Mo promoter of 0.41, the cobalt or nickel salts of the dimeric decamolybdocobaltate ion of formula Co2Mo10O38H46 ", 3Co2 + or Co2Mo10O38H46" i 3Ni2 + having an atomic ratio of said promoter (Co and / or Ni) / Mo of 0.5, the cobalt or nickel salts of the 6-molybdonickellate ion of formula NiMo6024H64 ", 2 Co2 + or NiMo6024H64", 2 Ni2 + having an atomic ratio of said promoter (Co and / or Ni) / Mo of 0.5 and the cobalt or nickel salts of the dimeric decamolybdonickellate ion of formula Ni2Mo10O38H48 ", 4Co2 + or Ni2Moi0O38H48", 4Ni2 + having an atomic ratio of said promoter (Co and / or Ni) / Mo of 0.6.

The most preferred Anderson heteropolyanion salts used in the invention are selected from the dimeric heteropolyanion salts containing cobalt and molybdenum within their structure of the formula Co2Moi0O38H46-, 3 Co2 + and Co2Moi0O38H46-, 3 Ni2 +. An even more preferred Anderson heteropolyanion salt is the dimeric Anderson heteropolyanion salt of the formula Co2Moi0O38H46-, 3 Co2 +. Other preferred polyoxometalates which can advantageously be reduced in the process according to the invention are the so-called heteropolyanions of Keggin of general formula XM12O40q "for which the ratio m / x is equal to 12 and the so-called lackeys of Keggin heteropolyanions of general formula XM11O39q" for which the ratio m / x is equal to 11 and in which the elements X and M and the charge q have the abovementioned meaning, X is therefore an element chosen from phosphorus (P), silicon (Si), boron (B), nickel (Ni) and cobalt (Co), said element being taken alone, M is one or more element (s) selected from molybdenum (Mo), tungsten (W), nickel (Ni) and cobalt (Co), and q being an integer of 1 to 20 and preferably between 3 and 12.

Said Keggin species are advantageously obtained for variable pH ranges according to the production routes described in the publication by A. Griboval, P. Blanchard, E. Payen, M. Fournier, JL Dubois, Chem. Lett., 1997, 12, 1259.

A preferred Keggin heteropolyanion, advantageously used according to the invention, is the heteropolyanion of formula ΡΜο12Ο403 "or PW12O403" or SiMo12O404 "or SiW12O404". The preferred Keggin heteropolyanion may also be advantageously used in the invention in its heteropolyacid form of formula PMo12O403 ", 3H + or PW12O403", 3H + or SiMo12O404 ", 4H + or SiW12O404", 4H +

Keggin or Keggin lacunar heteropolyanion salts may also be advantageously used according to the invention. Particularly preferred Keggin and Keggin-type heteropolyanion or heteropolyacid salts are selected from cobalt or nickel salts of phosphomolybdic, silicomolybdic, phosphotungstic or silicitungstic acids. Said heteropolyanion or heteropolyacid salts of the Keggin or Keggin lacunary type are described in the patent US2547380. Preferably, a Keggin-type heteropolyanion salt is nickel phosphotungstate of formula 3 / 2Ni 2+, PW 12 O 403 "having an atomic ratio of the Group VIB metal to the Group VIII metal, ie Ni / W of 0.125. .

Another preferred polyoxometallate which can advantageously be used as a reduced precursor used in the process according to the invention is Strandberg heteropolyanion of formula HhP2Mo5023 (6 "h)", h being equal to 0, 1 or 2 and for which the ratio m / x is equal to 5/2.

The preparation of said heteropolyanions of Strandberg and in particular of said heteropolyanion of formula HhP2Mo5023 (6 "h)" is described in the article of WC. Cheng, NP Luthra, J. Catal., 1988, 109, 163.

Thus, thanks to various preparation methods, many polyoxometalates and their associated salts are available. In general, all these polyoxometalates and their associated salts can be advantageously used in the process according to the invention. The foregoing list is however not exhaustive and other combinations may be envisaged.

Precursors comprising at least one Group VIII metal:

The preferred group VIII elements are non-noble elements: they are chosen from Ni, Co and Fe. Preferably, the group VIII elements are Co and Ni. The Group VIII metal can be introduced in the form of salts, chelating compounds, alkoxides or glycoxides. The sources of group VIII elements which can advantageously be used in the form of salts, are well known to those skilled in the art. They are chosen from nitrates, sulphates, carbonates, hydroxides, phosphates, acetylacetonates, acetates, formates and halides chosen from chlorides, bromides and fluorides.

Said precursor comprising at least one group VIII metal is at least partially soluble in the aqueous phase or in the organic phase. The solvents used are generally water, an alkane, an alcohol, an ether, a ketone, a chlorinated compound or an aromatic compound. Acidified water, toluene, benzene, dichloromethane, tetrahydrofuran, cyclohexane, n-hexane, ethanol, methanol and acetone are preferably used.

The Group VIII metal is preferably introduced in the form of acetylacetonate or acetate when an organic solvent is used, and in the form of hydroxides or carbonates or hydroxycarbonates when the solvent is water. at acidic pH. Another preferred way is to dissolve the group VIII metal introduced in the form of carbonate in an ammoniacal medium.

Description of the steps of the preparation process

Step a) Step a) during which at least partially metal group VIII metal precursor particles are formed on the catalyst support, is decomposed in several steps. Step a) comprises the following substeps: i) at least one step of contacting at least one catalytic precursor comprising at least one Group VIII metal with the porous support; ii) optionally, at least one maturation step if step i) is an impregnation; iii) optionally, at least one drying step if step i) is an impregnation; iv) optionally, a step of reducing the catalyst precursor comprising at least one Group VIII metal obtained in step i) or iii) if at least one Group VIII metal is not in metallic form.

The deposition of the catalytic precursor comprising at least one Group VIII metal on said support, in accordance with the implementation of said step i), can be carried out by any method well known to those skilled in the art. In particular, said step i) can be carried out by impregnation, dry or in excess, according to methods that are well known to a person skilled in the art, or else by chemical vapor deposition (CVD or "chemical vapor deposition" according to the terminology Anglo-Saxon).

Said step i) is preferably carried out by impregnation of the support consisting, for example, in bringing said support into contact with at least one aqueous and / or organic solution (for example methanol or ethanol or phenol or acetone or toluene or dimethylsulfoxide (DMSO)) or consists of a mixture of water and at least one organic solvent, comprising at least one catalytic precursor comprising at least one metal of group VIII at least partially in the dissolved state, or still in contacting said support with at least one colloidal solution of at least one catalytic precursor comprising at least one metal of group VIII, in oxidized form (nanoparticles of oxide, oxy (hydroxide) or hydroxide of group VIII metal) or in reduced form (metal nanoparticles of the Group VIII metal in the reduced state). The pH of the solution may be modified by the possible addition of an acid or a base. According to another preferred variant, the aqueous solution may contain ammonia or ammonium ions NH4 +.

Preferably, said step i) is carried out by dry impregnation, which consists in bringing the support of the catalyst into contact with a solution containing at least one catalytic precursor comprising at least one metal of group VIII, the volume of the solution of which is between 0.25 and 1.5 times the pore volume of the support to be impregnated.

When the catalytic precursor comprising at least one group VIII metal is introduced in aqueous solution, a precursor in the form of nitrate, carbonate, chloride, sulfate, hydroxide, hydroxycarbonate, formate, is advantageously used. acetate, oxalate, complexes formed with acetylacetonates, or complex tetramine or hexamine, or any other soluble inorganic derivative in aqueous solution, which is brought into contact with said support. When the Group VIII metal is nickel, nickel-based precursor is advantageously used, nickel nitrate, nickel carbonate, nickel chloride, nickel hydroxide, nickel hydroxycarbonate. Very preferably, the nickel precursor is nickel nitrate, nickel carbonate or nickel hydroxide.

The quantity of the precursor (s) comprising at least one Group VIII metal introduced in step a) is chosen such that the total content of group VIII element is between 1 and 8% by weight in group VIII element, preferably between 0.5 and 5% by weight relative to the total weight of the final catalyst.

When carrying out a step i) of impregnating the catalytic precursor comprising at least one group VIII metal with the porous support, a subsequent step ii) maturation (optional) and a step iii) drying are carried out subsequently. Stage ii) is a maturation stage intended to allow the species to spread to the core of the support. It is generally carried out at a temperature of between 17 to 50 ° C and advantageously in the absence of oxygen (O2), preferably between 30 minutes and 24 hours at room temperature.

The drying of the precursor obtained in step i) or ii) is intended to evacuate the impregnating solvent. The temperature should not exceed 250 ° C, preferably 180 ° C, to keep intact said precursors deposited on the surface of the support. Even more preferably, the temperature will not exceed 120 ° C. This step can be performed by passing an inert gas stream. The drying time is between 30 minutes and 24 hours. Preferably, the drying time is less than 12 hours, very preferably it is less than 4 hours. The step iv) of reducing the catalytic precursor comprising at least one group VIII metal can be carried out by any chemical treatment known to those skilled in the art or by heat treatment in the presence of a reducing gas after steps i) or iii ) so as to obtain a catalyst precursor comprising a catalytic precursor comprising at least one metal of group VIII at least partially in metallic form. Preferably, the reduction step is carried out by heat treatment in the presence of a reducing gas. This step is carried out when the bringing into contact of the porous support is carried out with a solution of at least one catalytic precursor comprising at least one Group VIII metal in not completely reduced form (ie in oxidized form).

The reducing gas is preferably hydrogen. The hydrogen can be used pure or as a mixture (for example a hydrogen / nitrogen mixture, or hydrogen / argon, or hydrogen / methane). In the case where the hydrogen is used as a mixture, all proportions are possible.

Said reducing treatment is carried out at a temperature between 120 and 500 ° C, preferably between 150 and 450 ° C.

The duration of the reducing treatment is generally between 2 and 40 hours, preferably between 3 and 30 hours. The rise in temperature to the desired reduction temperature is generally slow, for example set between 0.1 and 10 ° C / min, preferably between 0.3 and 7 ° C / min.

The flow rate of hydrogen, expressed in L / hour / g of catalyst, is between 0.01 and 100 L / hour / g of catalyst, preferably between 0.05 and 10 L / hour / g of catalyst, moreover more preferably between 0.1 and 5 L / hour / gram of catalyst.

Step b) The step b) of contacting the catalyst precursor obtained in step a) with an aqueous and / or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal is preferably carried out by a method of impregnation. The impregnation method is chosen from dry impregnation or excess impregnation. The so-called dry impregnation method is advantageously used, which comprises bringing the catalyst support into contact with a solution containing at least one catalytic precursor comprising at least one Group VIB metal, the volume of the solution of which is between 0.25 and 1.5 times the pore volume of the support to be impregnated. This impregnation is preferably carried out under an inert atmosphere (N 2 or Ar) or under a reducing atmosphere (H 2).

The solvent used in step b) is aqueous and / or organic. When the solvent is organic and the catalytic precursor comprising at least one Group VIB metal is a polyoxometalate, it generally consists of an alcohol. When the catalytic precursor comprising at least one Group VIB metal is a polyoxometalate, then water and ethanol are preferably used. Preferably, the solvents will be degassed in order to prevent the dissolved oxygen from reoxidizing the reduced elements.

During contacting, said catalytic precursor comprising at least one Group VIB metal will be completely or partially reduced and thus adopt a lower valence than VIB.

Step c) (optional) Step c) is a ripening step intended to allow the species to spread to the core of the support. It is carried out at a temperature of between 17 to 50 ° C and advantageously in the absence of oxygen (O2), preferably between 30 minutes and 24 hours at room temperature. The atmosphere is preferably free of O 2 so as to avoid reoxidizing the previously impregnated precursors.

Step d)

The drying carried out during step d) is intended to evacuate the impregnating solvent. The atmosphere is preferably free of O 2 so as to avoid reoxidizing the reduced pre-impregnated precursors. The temperature should not exceed 250 ° C, preferably 180 ° C, to keep intact said precursors deposited on the surface of the support. More preferably, the temperature will not exceed 120 ° C. Very preferably, the drying is carried out under vacuum at a temperature not exceeding 60 ° C. This step can be carried out alternately by the passage of an inert gaseous flow. The drying time is between 30 minutes and 24 hours. Preferably, the drying time is less than 12 hours and very preferably it is less than 4 hours.

Step e) (optional)

The dried catalyst obtained in stage d) is advantageously used in totally or partially sulphurized form. It therefore undergoes before use a step e) activation under sulfo-reducing atmosphere according to any method known to those skilled in the art, in situ or ex situ. The sulfurization treatment can be carried out ex situ (before the introduction of the catalyst into the hydrotreatment / hydroconversion reactor) or in situ by means of an organosulfur precursor agent of H2S, for example DMDS (dimethyl disulphide), n -butyl mercaptan and the polysulfide compounds. This sulphurization is carried out at a temperature between 200 and 600 ° C and preferably between 300 and 400 ° C according to methods well known to those skilled in the art.

Catalyst

The hydro-dehydrogenating function of the catalyst is provided by a Group VIB element and by at least one Group VIII element. Advantageously, the hydro-dehydrogenating function is chosen from the group formed by combinations of nickel-molybdenum or cobalt-molybdenum or nickel-cobalt-molybdenum or nickel-tungsten or nickel-molybdenum-tungsten elements.

The content of molybdenum (Mo) is generally between 4 and 30% by weight of element Mo relative to the final catalyst, and preferably between 7 and 25% by weight relative to the final catalyst, obtained after the last stage of preparation, before the implementation in the hydrotreatment process or the hydrocracking process.

The tungsten content (W) is generally between 7 and 40% by weight of element W relative to the final catalyst, and preferably between 12 and 30% by weight relative to the final catalyst, obtained after the last stage of preparation, before the implementation in the hydrotreatment process or the hydrocracking process.

The surface density, which corresponds to the quantity of molybdenum-Mo atoms deposited per surface unit of support, will advantageously be between 0.5 and 8 atoms of [Mo + W] per square nanometer of support and preferably between 2 and 7 atoms of [Mo + W] per square nanometer of support.

The promoter elements of group VIII are advantageously present in the catalyst at contents of between 0.1 and 8% by weight of group VIII element, preferably between 0.5 and 5% by weight relative to the final catalyst obtained after the last stage. of preparation, before implementation in the hydrotreatment process or the hydrocracking process.

The support of the catalyst of the invention is a porous support comprising at least one refractory oxide, advantageously comprising at least aluminum and / or at least silicon.

Preferably, said support comprises at least one aluminum oxide or at least one silicon oxide. Said support may advantageously be acidic. Said support can advantageously be mesostructured or not.

Said porous mineral support may advantageously be chosen from transition aluminas, doped alumina, preferably phosphorus, boron and / or fluorine, silicalite and silicas, aluminosilicates, preferably amorphous or partially crystallized, molecular sieves Non-zeolitic crystallized materials such as silicoaluminophosphates, aluminophosphates, ferrosilicates, titanium silicoaluminates, borosilicates, chromosilicates and transition metal aluminophosphates, alone or as a mixture.

In the case where said porous mineral support is chosen from transition aluminas, silicalite and silicas, such as, for example, mesoporous silicas, said support is not acidic. By transition alumina is meant, for example, an alpha phase alumina, a delta phase alumina, a gamma phase alumina or a mixture of alumina of these different phases.

In the case where said porous mineral support is chosen from aluminosilicates, preferably amorphous or partially crystallized, crystallized non-zeolitic molecular sieves such as silicoaluminophosphates, aluminophosphates, ferrosilicates, titanium silicoaluminates, borosilicates, chromosilicates and aluminophosphates of transition metals, doped alumina, preferably phosphorus, boron and / or fluorine, said support is acidic. Any known silica-alumina or aluminosilicate known to those skilled in the art is suitable for the invention.

When said porous mineral support is said to be mesostructured, it then comprises elementary particles organized at the mesopore scale of the material according to the invention, that is to say a pore-scale organized porosity having a uniform uniform diameter. between 1.5 and 50 nm, preferably between 1.5 and 30 nm and even more preferably between 4 and 20 nm and distributed homogeneously and uniformly in each of said particles (mesostructuration). The material located between the mesopores of the mesostructured elementary particle is amorphous and forms walls, or walls, whose thickness is between 1 and 30 nm and preferably between 1 and 10 nm. The thickness of the walls corresponds to the distance separating a first mesopore from a second mesopore, the second mesopore being the pore closest to the first mesopore. The organization of the mesoporosity described above leads to a structuring of said constituent particle of said support, which may be hexagonal, vermicular or cubic and preferably hexagonal. Preferably, said mesostructured porous mineral support is selected from silica and silica alumina.

The porous mineral support according to the invention, whether it is acidic or not, mesostructured or not, may also advantageously contain, in addition to at least one of the oxides compounds mentioned above, at least one zeolite and in particular non-restrictively those listed in "Atlas of zeolite framework types", 6th revised edition, 2007, Ch. Baerlocher, LBLMcCusker, DH Oison. "The zeolitic crystals may be selected from zeolites IZM-2, ZSM-5, ZSM-12 , ZSM-48, ZSM-22, ZSM-23, ZBM-30, EU-2, EU-11, Silicalite, Beta, Zeolite A, Faujasite, Y, USY, VUSY, SDUSY, Mordenite, NU-10, NU- 87, NU-88, NU-86, NU-85, IM-5, IM-12, IM-16, Ferrierite and EU-1. Very preferably, the zeolite crystals can be chosen from zeolites of structural type MFI , BEA, FAU, and LTA Different zeolitic crystals and especially zeolites of different structural type may be present in the porous mineral support constituting In particular, the porous mineral support according to the invention may advantageously comprise at least first zeolitic crystals whose zeolite is chosen from IZM-2, ZSM-5, ZSM-12 and ZSM zeolites. -48, ZSM-22, ZSM-23, ZBM-30, EU-2, EU-11, Silicalite, Beta, Zeolite A, Faujasite, Y, USY, VUSY, SDUSY, Mordenite, NU-10, NU-87, NU-88, NU-86, NU-85, IM-5, IM-12, IM-16, Ferrierite and EU-1, preferably among the structural type zeolites MFI, BEA, FAU, and LTA and at least second zeolitic crystals whose zeolite is different from that of the first zeolitic crystals and is chosen from zeolites IZM-2, ZSM-5, ZSM-12, ZSM-48, ZSM-22, ZSM-23, ZBM-30, EU- 2, EU-11, Silicalite, Beta, Zeolite A, Faujasite, Y, USY, VUSY, SDUSY, Mordenite, NU-10, NU-87, NU-88, NU-86, NU-85, IM-5, IM -12, IM-16, Ferrierite and EU-1, preferably among the structural type zeolites MFI, BEA, FAU, and LTA. The zeolitic crystals advantageously comprise at least one zeolite which is either entirely silicic or contains, in addition to silicon, at least one element T chosen from among aluminum, iron, boron, indium, gallium and germanium, preferably aluminum.

The porous mineral support may also advantageously contain, in addition to at least one of the above-mentioned oxide compounds, at least one synthetic or natural simple clay of 2: 1 dioctahedral phyllosilicate or 3: 1 trioctahedral phyllosilicate type, such as kaolinite, antigorite, chrysotile, montmorillonnite, beidellite, vermiculite, talc, hectorite, saponite, laponite. These clays can be optionally delaminated.

Preferably, said porous mineral support is chosen from mesoporous alumina and silica alumina, taken alone or as a mixture, or mesostructured silicas and silica aluminas, taken alone or as a mixture. Very preferably, said porous mineral support is a mesoporous alumina silica.

The support used for the preparation of the catalyst according to the invention advantageously has a total pore volume (VPT) of at least 0.5 ml / g, preferably at least 0.6 ml / g, and very preferably at least 0.7 ml / g.

The support of the catalyst used according to the present invention advantageously has a BET specific surface area (SS) greater than 75 m 2 / g, preferably greater than 100 m 2 / g, very preferably greater than 130 m 2 / g. By BET surface is meant the specific surface area determined by nitrogen adsorption according to ASTM D 3663-78 established from the method BRUNAUER - EMMET - TELLER described in the journal "The Journal of the American Chemical Society", 60 , 309 (1938).

The catalyst obtained by the preparation process according to the invention is generally presented in all the forms known to those skilled in the art. Preferably, it will consist of extrudates of diameter generally between 0.5 and 10 mm, preferably between 0.8 and 3.2 mm and very preferably between 1.0 and 2.5 mm. This may advantageously be in the form of extruded cylindrical, trilobed or quadrilobed. Preferably its shape will be trilobed or quadrilobed. The shape of the lobes can be adjusted according to all known methods of the prior art. Different layouts can be mixed.

Hydrotreatment Process / Hydrocracking Process

Another subject of the invention is the use of the catalyst according to the invention in processes for hydrotreatment or hydrocracking of hydrocarbon feedstocks (petroleum fractions or ex-biomass cuts).

The catalyst prepared with the process according to the invention can advantageously be used in any process known to those skilled in the art, requiring hydrotreatment and hydrocracking reactions of the hydrocarbon cuts. The hydrotreatment and hydrocracking processes according to the invention can advantageously be implemented in any type of reactor operated in a fixed bed or in a moving bed or in a bubbling bed. Preferably, said hydrotreatment process or said hydrocracking process is carried out in a reactor operated in a fixed bed.

The catalysts obtained by the preparation method according to the invention are advantageously used for the hydrotreatment reactions of hydrocarbon feedstocks such as petroleum cuts, cuts from coal or hydrocarbons produced from natural gas and more particularly requiring reactions. hydrogenation: mention the reactions of hydrogenation of aromatics, hydrodenitrogenation, hydrodesulfurization, hydrodemetallation or hydrocracking of hydrocarbon feedstocks.

These catalysts can also advantageously be used during the pretreatment of catalytic cracking feeds or the hydrodesulfurization of residues or the deep hydrodesulfurization of gas oils (ULSD Ultra Low Sulfur Diesel).

The feedstocks employed in the hydrotreatment processes are, for example, gasolines, gas oils, vacuum gas oils, atmospheric residues, vacuum residues, atmospheric distillates, vacuum distillates, heavy fuels, oils, waxes. and paraffins, used oils, residues or deasphalted crudes, feeds from thermal or catalytic conversion processes, alone or in mixtures, feedstocks from biomass or biomass conversion. These include oils and fats of plant or animal origin, pyrolysis oils or mixtures of such fillers.

The feeds which are treated, and in particular those mentioned above, generally contain heteroatoms such as sulfur, oxygen and nitrogen and, for heavy petroleum feedstocks, they most often also contain metals.

The operating conditions used in the processes implementing the hydrotreatment reactions of hydrocarbon feedstocks described above are generally the following: the temperature is advantageously between 180 and 450 ° C., and preferably between 250 and 440 ° C., the pressure is advantageously between 0.5 and 30 MPa, and preferably between 1 and 18 MPa, the hourly volume velocity is advantageously between 0.1 and 20 h -1 and preferably between 0.2 and 5 h -1, and the hydrogen / charge ratio expressed as a volume of hydrogen, measured under normal conditions of temperature and pressure, per volume of liquid charge is advantageously between 50 l / l to 2000 l / l.

The feedstocks employed in the hydrocracking reactions are, for example, LCOs (light cycle oil (light gas oils from a catalytic cracking unit)), atmospheric distillates, vacuum distillates, for example gas oils obtained from the direct distillation of crude oil. or conversion units such as FCC, coker or visbreaking, feeds from aromatics extraction units, lubricating oil bases or from solvent dewaxing of lubricating oil bases, distillates from fixed-bed or bubbling-bed desulfurization or hydroconversion processes, atmospheric residues and / or vacuum residues and / or deasphalted oils, or the filler may be a deasphalted oil or include vegetable oils or else come from the conversion of charges from biomass. These different fillers can be hydrocracked or partially partially or completely hydrotreated, said hydrocarbon feedstock treated according to the hydrocracking process of the invention can also be a mixture of said previously mentioned fillers. The hydrocarbon compounds present in said feedstock are aromatic compounds, olefinic compounds, naphthenic compounds and / or paraffinic compounds.

Said hydrocarbon feedstock advantageously comprises heteroatoms. In a preferred manner, said heteroatoms are chosen from nitrogen, sulfur and the mixture of these two elements. When the nitrogen is present in said feedstock to be treated, the nitrogen content is greater than or equal to 500 ppm by weight, preferably it is between 500 and 10,000 ppm by weight, more preferably between 700 and 4000 ppm by weight and so even more preferred between 1000 and 4000 ppm by weight relative to the total weight of the load. When the sulfur is present in said feedstock to be treated, the sulfur content is between 0.01 and 5% by weight, preferably between 0.2 and 4% by weight and even more preferably between 0.5 and 3%. % by weight relative to the total weight of the load.

Said hydrocarbon feed may optionally advantageously contain metals, in particular nickel and vanadium. The cumulative nickel and vanadium content of said hydrocarbon feedstock, treated according to the hydrocracking process according to the invention, is preferably less than 1 ppm by weight relative to the total weight of the feedstock. The asphaltene content of said hydrocarbon feedstock is generally less than 3000 ppm by weight, preferably less than 1000 ppm by weight, more preferably less than 200 ppm by weight relative to the total weight of the feedstock.

The hydrocracking process according to the invention covers the pressure and conversion ranges from mild hydrocracking to high pressure hydrocracking. Mild hydrocracking is understood to mean hydrocracking leading to moderate conversions, generally less than 40% by weight relative to the total weight of the filler, and operating at low pressure, generally between 2 MPa and 10 MPa. The hydrocracking process according to the invention is carried out in the presence of at least one hydrotreatment or hydrocracking catalyst according to the invention. The hydrocracking process according to the invention can be carried out in one or two stages, independently of the pressure at which said process is implemented. It is carried out in the presence of one or more catalyst (s) obtained according to the preparation method described above, in one or more reaction unit (s) equipped with one or more reactors ( s).

The operating conditions used in the hydrocracking processes according to the invention can be very variable depending on the nature of the feedstock, the quality of the desired products and the facilities available to the refiner. According to the hydrocracking process according to the invention, said hydrocracking catalyst is advantageously brought into contact, in the presence of hydrogen, with said hydrocarbon feedstock at a temperature above 200 ° C., often between 250 and 480 ° C. advantageously between 320 and 450 ° C, preferably between 330 and 435 ° C, under a pressure greater than 0.5 MPa, often between 2 and 25 MPa, preferably between 3 and 20 MPa, the space velocity (flow the volume of charge divided by the volume of the catalyst) being between 0.1 and 20 h -1 and preferably between 0.1 and 6 h -1, even more preferably between 0.2 and 3 h -1, and the quantity of hydrogen introduced is such that the ratio by volume of hydrogen liter / liter of hydrocarbon is between 80 and 5000 l / l and most often between 100 and 2000 l / l.

These operating conditions used in the hydrocracking process according to the invention generally make it possible to achieve pass conversions, in products having boiling points of at most 370 ° C. and advantageously at most 340 ° C., superior. at 15% by weight and even more preferably between 20 and 95% by weight relative to the total weight of the filler.

The following examples illustrate the present invention without, however, limiting its scope.

Example 1 Preparation of a Porous Support of the Alumina Silica Type Containing Ni Particles

A silica alumina support of SBet = 250 m 2 / g and a pore volume equal to 0.65 ml / g is impregnated dry with an aqueous solution of nickel nitrate with a Ni concentration of 0.6 mol / l. After a maturation step of 12 h in air, the solid is dried at 120 ° C in air for 12 h, then it is calcined in air at 450 ° C for 2 h leading to a departure of nitrate ions. A support containing particles of nickel oxide (NiO) is obtained. It is then subjected to a thermal reduction step under H 2 at 400 ° C. for 16 h, allowing the reduction of NiO to nickel metal (oxidation state 0). The silica-alumina support containing the NiO particles is then maintained under an inert atmosphere of argon.

EXAMPLE 2 Preparation of Catalyst C1 (in Accordance with the Invention) by Impregnation of Polyoxometalates with the Solid From Example 1 (Silica-Alumina Support Containing NiO 2 Particles)

In a second step, the solid obtained in Example 1 is impregnated to 99% of its pore volume with an ethanolic solution of phosphomolybdic acid (H3PMo12O40) at 3 M in the absence of oxygen (impregnation under an inert atmosphere) . A maturation step is then carried out under argon and for 16 hours. The solid is then dried under vacuum using a rotary evaporator at a temperature not exceeding 60 ° C. The final solid obtained is of sustained blue color.

The catalyst C1 thus obtained (Mo = 12.5% by weight of Mo element relative to the weight of the final catalyst, Ni / Mo = 0.2 and P / Mo = 0.08) is stored under an inert atmosphere or under reduced pressure before use.

Example 3 Preparation of a Porous Alumina-Type Support Containing Ni Particles

An aqueous solution of ammonia (32%) and ammonium carbonate (250 g / l) is prepared. Nickel carbonate is added to a concentration of 350/1. A clear blue solution is obtained. A porous alumina support having a SBand equal to 280 m 2 / g and a pore volume of 0.7 ml / g is impregnated with a volume of this solution corresponding to 99% of its pore volume. After a maturation step carried out under argon for 16 h, the solid obtained is dried at ambient temperature for 16 h and then at 150 ° C. for 30 minutes, then it is subjected to a thermal reduction step under H 2 at 400 ° C. for 16 hours. h, leading to a departure of the nitrate icns and a reduction of the nickel nickel compounds to oxidation degree 0. The alumina support containing the NiO particles is then stored under an inert atmosphere of argon.

EXAMPLE 4 Preparation of the Catalyst C2 (in Accordance with the Invention) by Impregnation of Polyoxometalate on an Alumina-type Support Containing NiO Particles

In a second step, an aqueous solution of phosphomolybdic acid (H3PMo12O40) at 3 M is impregnated at 99% of the pore volume of the support containing the Ni particles (Example 3) in the absence of oxygen (impregnation under atmospheric conditions). inert). A maturation step is then carried out under argon for 16 hours. The support is then dried under vacuum using a rotary evaporator at a temperature not exceeding 60 ° C. The final impregnated and dried solid is of sustained blue color, reflecting the at least partial reduction of the metal centers of the polyoxometallate clusters.

The catalyst C2 thus obtained (Mo = 12% by weight of Mo element relative to the weight of the final catalyst, Ni / Mo = 0.2 and P / Mo = 0.08) is stored under an inert atmosphere or under reduced pressure before use.

EXAMPLE 5 Preparation of the C3 Catalyst (Non-Conforming) of NiMoP Formulation on a Silica-Alumina Support

A silica alumina support of SBet = 250 m 2 / g and a pore volume equal to 0.65 ml / g is impregnated dry with an aqueous solution of nickel nitrate with a concentration of Ni of 0.6 mol / l and H3PM0i2O40 concentration in Mo of 3 mol / l. After a maturation step of 12 hours in air, the solid is dried at 120 ° C in air for 12 hours.

The final solid obtained catalyst C3 has a Mo content of 12.1 wt.% Mo element relative to the weight of the final catalyst, and ratios Ni / Mo = 0.2 and P / Mo = 0.08. The final catalyst is stored under air before use.

Example 6 Preparation of the C4 Catalyst (Non-Conforming) of NiMoP Formulation on an Alumina Support

An alumina support of SBet = 280 m2 / g and a pore volume equal to 0.7 ml / g is impregnated dry with an aqueous solution of nickel nitrate of concentration of Ni of 0.6 mol / l and H3PMo1204o. concentration in MB of 3mol / l. After a 12-hour maturation step in air, the solid is dried at 120 ° C. under air for 12 hours.

The final solid obtained catalyst C4 has a Mo content of 12.2 wt.% Mo element relative to the weight of the final catalyst, and ratios Ni / Mo = 0.2 and P / Mo = 0.08. The final catalyst is stored under air before use.

EXAMPLE 7 Test for hydrogenation of toluene in the presence of aniline of catalysts C1 (according to the invention) and C3 (not in accordance with the invention)

The purpose of the toluene hydrogenation test is to evaluate the hydrogenating activity of the supported or bulk sulfurized catalysts in the presence of H 2 S and under hydrogen pressure.

Catalysts C1 and C3 are tested on the same test unit and under the same operating conditions.

The test is conducted in the gas phase, in a fixed bed reactor traversed. The test is broken down into two distinct phases, sulphidation and catalytic testing. The operating conditions of the activation phase and the test are as follows: P = 6 MPa, T = 350 ° C. and H> / charge = 450 l / l. The charge rates are equal to WH = 4 l / l / h during the activation phase (in-situ sulphurization), and WH = 2 l / l / h during the test phase. The test load is composed of dimethyl disulphide (DMDS), toluene, aniline and cyclohexane. Aniline is used to inhibit the acid function of the support by turning into NH3 during the test. It is also the charge that is used during the sulphidation.

sulphidation

The sulfurization or activation phase is carried out in situ, inside the catalytic reactor. The unactivated catalysts undergo a rise in temperature from room temperature to 350 ° C., in the presence of the charge described above with a temperature ramp of 2 ° C./min in a fixed bed tubular reactor traversed by a unit. Flowrence®-type driver (Avantium® manufacturer), fluids flowing from top to bottom. Once the temperature of 350 ° C is reached, the activation phase is maintained for 2 hours before starting the test phase.

Catalytic test:

Stabilized catalytic activities are measured for equal volumes of catalysts (450 μΙ) and at a temperature of 350 ° C. The measurements of hydrogenating activity are carried out 2 hours after reaching 350 ° C.

The effluent samples are analyzed by gas chromatography. The catalytic performances of the catalysts are expressed by means of the hydrogenating activity (AH) which corresponds, following a kinetic law of order 1, to the following formula:

with% HYD, 0 | Uene corresponds to the percentage of hydrogenated toluene.

The catalytic performances are collated in Table 1, hereinafter. They are expressed in relative activity, while that of catalyst C3 is equal to 100.

Table 1: Relative Hydrogenation Activities of Catalysts C1 (Compliant) and C3 (Non-Conforming).

Table 1 shows a gain in the important hydrogenating power obtained with the catalyst C1 according to the invention relative to the non-compliant catalyst C3. The catalyst C1, according to the invention, is more active in hydrogenation than the catalyst C3 which is its formulation counterpart, but prepared conventionally without the step of forming the Ni particles on the support.

EXAMPLE 8 Test for hydrogenation of toluene without aniline of the catalysts C2 (in accordance with the invention) and C4 (not in accordance with the invention)

Catalysts C2 and C4 are tested on the same test unit and under the same operating conditions.

The test is conducted in the gas phase, in a fixed bed reactor traversed. The test is broken down into two distinct phases, sulphidation and catalytic testing. The operating conditions of the activation phase and the test are as follows: P = 6 MPa, T = 350 ° C. and H> / charge = 450 l / l. The charge rates are equal to WH = 4 l / l / h during the activation phase (in-situ sulphurization), and WH = 2 l / l / h during the test phase. The test load is composed of dimethyl disulphide (DMDS), toluene, and cyclohexane. It is also the charge that is used during the sulphidation.

sulphidation

The sulfurization or activation phase is carried out in situ, inside the catalytic reactor. The unactivated catalysts undergo a rise in temperature from room temperature to 350 ° C., in the presence of the charge described above with a temperature ramp of 2 ° C./min in a fixed bed tubular reactor traversed by a unit. Flowrence type pilot (Avantium manufacturer), flowing fluids from top to bottom. Once the temperature of 350 ° C is reached, the activation phase is maintained for 2 hours before starting the test phase.

Catalytic test:

The effluent samples are analyzed by gas chromatography. The catalytic performances of the catalysts are expressed using the hydrogenating activity (AH) which corresponds to the formula (1) presented above in Example 7.

The catalytic performances are collated in Table 2. They are expressed in relative activity, while that of catalyst C4 is equal to 100.

Table 2: relative hydrogenating activities of catalysts C2 (compliant) and C4 (non-compliant).

Table 2 shows a gain in the high hydrogenating power obtained with the catalyst C2 according to the invention with respect to the non-compliant catalyst C4. The catalyst C2, according to the invention, is more active in hydrogenation than the catalyst C4 which is its formulation counterpart, but prepared conventionally without the step of forming the Ni particles on the support.

Claims

A process for preparing a hydrotreatment and / or hydrocracking catalyst comprising at least one active phase based on a Group VIB metal and a Group VIII metal, and a porous support comprising at least one refractory oxide, which process comprises at least the following steps: a) a step in which particles of at least one catalytic precursor comprising at least one metal of group VIII at least partially in metallic form on the porous support are formed; b) a step of contacting the catalyst precursor obtained in step a) with an aqueous and / or organic solution comprising at least one catalytic precursor comprising at least one Group VIB metal; c) optionally, a step of maturing the catalyst precursor obtained in step b) for 30 minutes to 24 hours; d) a step of drying the catalyst precursor obtained in step b) or c) at a temperature below 250 ° C, without further calcination, to obtain a dried catalyst.

2. Method according to claim 1, wherein step a) comprises at least the following substeps: i) a step of contacting at least one catalytic precursor comprising at least one metal of group VIII with the support porous, said contacting being carried out by impregnation, dry or in excess, or by chemical vapor deposition; ii) optionally, a ripening step for 30 minutes to 24 hours if step i) is an impregnation step; iii) optionally, a drying step at a temperature below 250 ° C if step i) is an impregnation, preferably less than 180 ° C; iv) optionally, a step of reducing the catalyst precursor comprising at least one Group VIII metal obtained in step i) or iii) if at least one Group VIII metal is not in metallic form.

3. Method according to claim 2, wherein the step i) of contacting is carried out by dry impregnation.

4. Method according to any one of claims 2 to 3, wherein step iv) is carried out in the presence of a reducing gas at a temperature between 120 and 500 ° C for a period of between 2 and 40 hours.

5. Process according to any one of claims 1 to 4, wherein the group VIII metal is selected from nickel, cobalt and iron.

6. Process according to any one of claims 2 to 5, wherein step i) is carried out by impregnation of a colloidal solution of the at least one catalytic precursor comprising at least one metal of group VIII, in oxidized form. .

7. Method according to any one of claims 2 to 5, wherein step i) is carried out by impregnation of a colloidal solution of the at least one catalytic precursor comprising at least one metal of group VIII, in reduced form. .

8. Process according to any one of claims 1 to 7, wherein said catalytic precursor comprising at least one metal of group VIB is chosen from polyoxometalates corresponding to the formula (HhXxMmOy) q "in which H is hydrogen, X is a member selected from phosphorus (P), silicon (Si), boron (B), nickel (Ni) and cobalt (Co), M is one or more metal (s) selected from molybdenum (Mo), tungsten (W), nickel (Ni) and cobalt (Co), where O is oxygen, h being an integer from 0 to 12, where x is an integer from 0 to 4, m being an integer equal to 5, 6, 7, 8, 9, 10, 11, 12 and 18, where y is an integer of 17 to 72 and q is an integer of 1 to 20, with the proviso that M is not a nickel atom or a cobalt atom alone.

The method of claim 8, wherein x = 0.

The process according to claim 8 or 9, wherein the m atoms M are either only molybdenum (Mo) atoms, or only tungsten (W) atoms, or a mixture of molybdenum (Mo) atoms and cobalt (Co), a mixture of molybdenum (Mo) and nickel (Ni) atoms, a mixture of tungsten (W) and nickel (Ni) atoms.

11. Process according to claim 8 or 9, in which the m atoms M are either a mixture of nickel (Ni), molybdenum (Mo) and tungsten (W) atoms, or a mixture of cobalt atoms ( Co), molybdenum (Mo) and tungsten (W).

12. Process according to any one of claims 1 to 11, wherein a c) maturation step is carried out at a temperature of between 17 and 50 ° C for 30 minutes to 24 hours in an atmosphere free of O2.

13. Process according to any one of claims 1 to 12, wherein the drying step d) is carried out at a temperature of less than or equal to 120 ° C, in an atmosphere free of O2.

14. A method according to any one of claims 1 to 13, wherein the porous support comprising at least one refractory oxide is selected from transition aluminas, doped alumina, preferably phosphorus, boron and / or fluorine, silicalite and silicas, aluminosilicates, preferably amorphous or partially crystallized, crystallized non-zeolitic molecular sieves such as silicoaluminophosphates, aluminophosphates, ferrosilicates, titanium silicoaluminates, borosilicates, chromosilicates and transition metal aluminophosphates , alone or in mixture.

15. Process for hydrotreatment or hydrocracking of a hydrocarbon feedstock in the presence of hydrogen and of a catalyst obtained by the process according to any one of claims 1 to 14 carried out at a temperature of between 180 and 450 ° C. C, a pressure between 0.5 and 30 MPq a hourly volume velocity (VVH) between 0.1 and 20 h "1, and wherein the amount of hydrogen introduced is such that the volumetric ratio of hydrogen per liter of hydrocarbon is between 50 and 5000 Nl / l.