Hydrocracking catalyst comprising zeolite Y dedicated for naphtha production

Abstract

The present invention describes a hydrocracking catalyst comprising at least one hydrogenation-dehydrogenation element selected from the group consisting of elements of Group VIB and non-noble elements of Group VIII of the periodic table, alone or as a mixture, and a support, the support comprises at least one porous inorganic matrix, a zeolite Y having an initial lattice parameter a0 of unit cells of between 24.40 and 24.52, a BET specific surface area of between 850 and 1020 m2 / g, a micropore volume of greater than 0.28 ml / g as measured by nitrogen adsorption and a Bronsted acidity of greater than 600 micromoles / g.

Description

[0014] Subject matter of the invention More particularly, the present invention relates to a hydrocracking catalyst selective for naphtha fractions, which comprises at least one hydro-dehydrogenating element selected from elements of Group VIB and non-noble elements of Group VIII of the Periodic Table, either alone or as a mixture, and a support which comprises at least one porous inorganic matrix, an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, a BET specific surface area between 850 and 1020 m 2 / g, a micropore volume greater than 0.28 ml / g measured by nitrogen adsorption and zeolite Y with a Bronsted acidity greater than 600 μmol / g.

[0015] Another subject of the present invention is a process for hydrocracking a hydrocarbon feedstock in the presence of said catalyst.

[0016] One advantage of the present invention is to provide a hydrocracking catalyst which, when the catalyst is used in the hydrocracking process according to the present invention, obtains improved selectivity for naphtha fractions as compared to catalysts of the prior art.

[0017] In the present invention, the selectivity of the hydrocracking catalyst for naphtha production is determined during the catalytic test and corresponds to the fraction, expressed as a weight percentage, of the products boiling in the naphtha fraction range, i.e., between the boiling temperature of hydrocarbon compounds containing 6 carbon atoms per molecule (or boiling point of 68 °C) and 216 °C, relative to the total mass of the products leaving the process.

[0018] According to an advantageous embodiment, the catalyst according to the present invention further comprises beta zeolite.

[0019] An advantage of this advantageous embodiment of the present invention is that it provides a hydrocracking catalyst which can not only obtain improved selectivity for naphtha fractions when the catalyst is used in the hydrocracking process according to the present invention, but also obtain improved activity as compared to catalysts of the prior art, which comprises said zeolite Y and beta zeolite with the claimed specific characteristics at a specific Y / beta mass ratio.

[0020] In the present invention, the conversion activity of the hydrocracking catalyst for naphtha production is determined by comparing the catalyst use temperature required to produce at least 65% by weight of products with a boiling point below 216 °C during the catalytic test. The lower the required temperature, the higher the activity of the catalyst. This temperature reduction makes it possible, for example, to limit the energy consumption of the process and increase the cycle time of using the catalyst, or even to process less reactive feedstocks without modifying the process capacity and scheme.

[0021] Throughout the following text, the term "specific surface area" refers to the BET specific surface area (SBET) measured by nitrogen adsorption according to the standard ASTM 4365-19 established by the Brunauer-Emmett-Teller method described in the journal The Journal of the American Chemical Society , 60, 309 (1938). Textural analysis by nitrogen adsorption also enables the determination of the micropore volume, i.e., the volume of pores with a pore diameter less than 2 nm. Before analysis, the zeolite powder is activated at 500 °C for 5 hours.

[0022] Similarly, the mesopore volume is determined by nitrogen adsorption. Throughout the following text, the term "micropore" refers to pores with a pore diameter less than 2 nm, and "mesopore" refers to pores with a pore diameter greater than 2 nm.

[0023] Throughout the following text, the Brønsted acidity of zeolite Y is measured by the adsorption of pyridine and subsequent thermal desorption, followed by infrared spectroscopy (FTIR). As described in the journal C.A. Emeis, Journal of Catalysis , 141, 347 (1993), this method is routinely used to characterize acidic solids such as zeolite Y. Before analysis, the zeolite powder is compacted into the form of pellets with a diameter of 16 mm and activated at 450 °C under secondary vacuum. Pyridine is introduced into the gas phase in contact with the activated pellets and a thermal desorption step is carried out at 150 °C. The concentration of pyridinium ions detected by FTIR after thermal desorption at 150 °C corresponds to the Brønsted acidity of the zeolite and is expressed in micromoles per gram.

[0024] For the present invention, the various embodiments given can be used alone or in combination with each other without any limitation on the combination.

[0025] For the present invention, the various parameter ranges of a given step, such as the pressure range and the temperature range, can be used alone or in combination. For example, for the present invention, the preferred range of pressure values can be combined with the range of more preferred temperature values.

[0026] In the following text, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, edited by D.R. Lide, 81st edition, 2000-2001). For example, Group VIII according to the CAS classification corresponds to the metals in columns 8, 9, and 10 according to the new IUPAC classification, while Group VIB corresponds to the metals in column 6.

[0027] In the following text, the expressions "of between... and..." and "between... and..." are equivalent and mean that the limiting values of the interval are included within the described numerical range. If this is not the case and if the limiting values are not included within the described range, the present invention will provide such clarification.

[0028] In this specification, the term "greater than..." is understood to be strictly greater than and is represented by the symbol ">", and the term "less than" is understood to be strictly less than and is represented by the symbol "<".

[0029] In this specification, the total SiO2 / Al2O3 molar ratio of the zeolite is also referred to as the SAR or silica-alumina ratio. The SiO2 / Al2O3 molar ratio is measured by X-ray fluorescence. DETAILED DESCRIPTION OF THE INVENTION Hydrogenation / dehydrogenation functionality According to the present invention, the catalyst comprises at least one hydrogenation-dehydrogenation element selected from the elements of Group VIB and non-noble elements of Group VIII of the Periodic Table, either alone or as a mixture.

[0031] Preferably, the Group VIII element is selected from iron, cobalt and nickel, either alone or as a mixture, and preferably from nickel and cobalt. Preferably, the Group VIB element is selected from tungsten and molybdenum, either alone or as a mixture. The following metal combinations are preferred: nickel-molybdenum, cobalt-molybdenum, nickel-tungsten, cobalt-tungsten, and very preferably: nickel-molybdenum, nickel-tungsten. Combinations of three metals can also be used, such as nickel-cobalt-molybdenum.

[0032] Relative to the total weight of the catalyst, the content of the Group VIII element in the catalyst is advantageously between 0.5% and 8% by weight of the oxide, preferably between 0.5% and 6% by weight of the oxide, and very preferably between 1.0% and 4% by weight of the oxide. Relative to the total weight of the catalyst, the content of the Group VIB element in the catalyst is advantageously between 1% and 30% by weight of the oxide, preferably between 2% and 25% by weight of the oxide, and very preferably between 5% and 20% by weight of the oxide, and even more preferably between 5% and 16% by weight of the oxide.

[0033] Preferably, the catalyst used according to the present invention may also contain promoter elements selected from phosphorus, boron and silicon, and very preferably phosphorus. When the catalyst contains phosphorus, the phosphorus content is advantageously between 0.5% and 10% by weight of the P2O5 oxide, preferably between 1% and 6% by weight of the P2O5 oxide, and more preferably between 1% and 4% by weight of the P2O5 oxide, relative to the total weight of the catalyst.

[0034] Support The catalyst according to the invention comprises a support which comprises and preferably consists of at least one porous inorganic matrix, zeolite Y, preferably dealuminated zeolite USY, said zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, a BET specific surface area between 850 and 1020 m 2 / g, a micropore volume greater than 0.28 ml / g and a Bronsted acidity greater than 600 μmol / g.

[0035] The porous inorganic matrix used in the support of the catalyst, also known as the binder, advantageously consists of at least one refractory oxide, which is preferably selected from alumina, silica-alumina, clay, titanium oxide, boron oxide and zirconia, either alone or as a mixture. Preferably, the porous inorganic matrix is selected from alumina and silica-alumina, either alone or as a mixture. More preferably, the porous inorganic matrix is alumina. Alumina can advantageously be in any form known to those skilled in the art. Very preferably, the alumina is γ-alumina, such as boehmite.

[0036] Preferably, relative to the total weight of the support, the support comprises 15 wt% to 55 wt% of the binder, preferably 25 wt% to 50 wt%, and very preferably 25 wt% to 40 wt%.

[0037] According to the invention, the support comprises zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å.

[0038] Preferably, the initial lattice parameter a0 of the unit cell of the zeolite Y used is between 24.40 and 24.51 Å, preferably between 24.43 and 24.51 Å, and very preferably between 24.45 and 24.48 Å.

[0039] The initial lattice parameter a0 of the unit cell of a given zeolite Y is the value of the initial lattice parameter a0 of the zeolite Y used in the synthesis of the catalyst according to the invention.

[0040] The initial lattice parameter a0 of the unit cell of zeolite Y is measured by X-ray diffraction according to standard ASTM D3942-80.

[0041] According to the invention, the zeolite Y has a specific surface area measured by physical adsorption of nitrogen according to the BET method between 850 and 1020 m 2 / g, preferably between 875 and 995 m 2 / g, and preferably between 900 and 970 m 2 / g.

[0042] According to the present invention, the zeolite Y has a micropore volume measured by nitrogen adsorption of greater than 0.28 ml / g, preferably greater than 0.30 ml / g, and advantageously greater than 0.31 ml / g, and advantageously less than 0.34 ml / g.

[0043] According to the present invention, the zeolite Y has a Bronsted acidity of greater than 600 μmol / g, preferably greater than 650 μmol / g, preferably greater than 700 μmol / g, and very preferably greater than 760 μmol / g. Preferably, the zeolite Y has a Bronsted acidity of less than 1000 μmol / g.

[0044] Preferably, the zeolite Y has a silica / alumina molar ratio (SAR) between 5 and 50, preferably between 5 and 20, and more preferably between 5 and 10.

[0045] Preferably, the zeolite Y has a mesopore volume of greater than or equal to 0.18 ml / g, preferably between 0.18 and 0.27 ml / g, preferably between 0.20 and 0.26 ml / g, and very preferably between 0.22 and 0.25 ml / g.

[0046] Preferably, based on the total weight of the carrier, the carrier has a content of zeolite Y, preferably dealuminated zeolite USY, between 15 wt% and 80 wt%, preferably between 20 wt% and 75 wt%, and preferably between 40 wt% and 75 wt%.

[0047] The zeolite is advantageously defined in "Atlas of Zeolite Framework Types, 6th Revised Edition", Ch. Baerlocher, L. B. McCusker, D.H. Olson, 6th Edition, Elsevier, 2007, Elsevier.

[0048] According to a preferred embodiment of the present invention, zeolite Y having a combination of specific characteristics defined above and suitable for use as a catalyst support in the process according to the present invention is advantageously prepared according to a preparation method known to those skilled in the art. Advantageously, zeolite Y having a combination of specific characteristics defined above and suitable for use as a catalyst support in the process according to the present invention is obtained according to a preparation method comprising several steps. In these steps, the mixing of at least one alkali metal, at least one organic compound R (R is a quaternary ammonium formed by a carbon-based chain containing 1 to 4 carbon atoms), at least one silicon source SiO2 and at least one aluminum source Al2O3 in an aqueous medium enables the obtaining of a homogeneous mixture called a precursor gel. This precursor gel can undergo an optional aging step and an optional step involving the addition of seeds of zeolite of the FAU structure type. At the end of these optional steps, the precursor gel undergoes hydrothermal treatment until the formation of said zeolite Y.

[0049] Thus, the obtained zeolite Y has an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, a specific surface area measured by physical adsorption of nitrogen by the BET method between 850 and 1020 m 2 / g, a micropore volume greater than 0.28 ml / g measured by nitrogen adsorption and a Bronsted acidity greater than 600 μmol / g.

[0050] The support may advantageously further comprise zeolite β.

[0051] Zeolite β is generally synthesized from a reaction mixture containing a structuring agent. The use of structuring agents is well known to those skilled in the art: for example, patent US 3 308 069 describes the use of tetraethylammonium hydroxide, and patent US 5 139 759 describes the use of tetraethylammonium cations derived from tetraethylammonium halide compounds. Another standard method for preparing zeolite β is given in the book "Verified Synthesis of Zeolitic Materials".

[0052] The zeolite β used in the support according to the present invention preferably has a total SAR atomic ratio between 10 and 100, preferably between 20 and 50, and more preferably between 20 and 30. The zeolite β used in the support according to the present invention advantageously has a specific surface area measured by physical adsorption of nitrogen by the BET method between 400 and 800 m 2 / g, preferably between 500 and 750 m 2 / g, and preferably between 550 and 700 m 2 / g.

[0053] When the support contains zeolite β, advantageously, the support has a zeolite β content of between 2% by weight and 40% by weight, preferably between 5% by weight and 35% by weight, and more preferably between 10% by weight and 35% by weight, based on the total weight of the support.

[0054] When the support contains zeolite β, the weight ratio of zeolite Y to zeolite β in the catalyst is between 1 and 40.

[0055] Preferably, the weight ratio of zeolite Y to zeolite β in the catalyst is between 1 and 20, preferably between 1.2 and 15, and more preferably between 1.2 and 8.

[0056] This weight ratio is calculated from the dry mass of the zeolite, i.e., the mass of the zeolite corrected for its water content (dry mass) measured by determining the loss on ignition at 1000 °C.

[0057] When the support contains only zeolite USY (without zeolite β), it preferably consists of the following components: - from 15% by weight to 80% by weight, preferably from 20% by weight to 70% by weight, and more preferably from 40% by weight to 70% by weight of zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, preferably dealuminated zeolite USY, based on the total weight of the support; - from 20% by weight to 85% by weight, preferably between 20% by weight and 60% by weight, and very preferably between 20% by weight and 50% by weight of at least one porous inorganic matrix, based on the total weight of the support.

[0058] When the support contains zeolite USY and zeolite β, it preferably consists of the following components: - from 15% by weight to 80% by weight, preferably from 20% by weight to 70% by weight, and more preferably from 40% by weight to 70% by weight of zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, preferably dealuminated zeolite USY, based on the total weight of the support; - from 2% by weight to 40% by weight, preferably from 5% by weight to 35% by weight, or from 10% by weight to 35% by weight of zeolite β; and - from 5% by weight to 83% by weight, preferably between 15% by weight and 40% by weight, and very preferably between 20% by weight and 40% by weight of at least one porous inorganic matrix, based on the total weight of the support.

[0059] Preferably, the catalyst has a zeolite Y content of between 7% by weight and 78% by weight, based on the total weight of the catalyst.

[0060] Preferably, in the presence of zeolite β in the catalyst formulation, the catalyst has a zeolite β content between 2% by weight and 39% by weight relative to the total weight of the catalyst.

[0061] Preferably, the catalyst has a content of at least one porous inorganic matrix between 4% by weight and 81% by weight relative to the total weight of the catalyst.

[0062] Advantageously, a hydrocracking catalyst having a Y / β ratio within these ranges can not only obtain improved selectivity to the naphtha fraction compared to prior art catalysts when the catalyst is used in the hydrocracking process according to the present invention, but also obtain improved activity.

[0063] Preparation of the catalyst The catalyst is advantageously prepared according to conventional methods used in the prior art.

[0064] In particular, the catalyst is prepared according to a preparation method comprising the following steps: - A step of preparing a support, which comprises: - Mixing at least one porous inorganic matrix with zeolite Y and optionally with zeolite β, the zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, a specific surface area measured by physical adsorption of nitrogen using the BET method between 850 and 1020 m 2 / g, a micropore volume greater than 0.28 ml / g measured by nitrogen adsorption, and a Bronsted acidity greater than 600 μmol / g, and in the presence of zeolite β, the weight ratio of the zeolite Y to the zeolite β in the catalyst is between 1 and 40, and - Shaping the mixture; - Introducing at least one hydro-dehydrogenation element selected from elements of Group VIB of the periodic table, preferably nickel and cobalt, non-precious elements of Group VIII of the periodic table, preferably iron, cobalt, nickel and mixtures thereof, and preferably nickel and cobalt and mixtures thereof, onto the support as follows: - Adding at least one precursor of the element during the shaping process to introduce at least a portion of the element, - Impregnating the support with at least one precursor of the element, - Optionally, a step of drying and / or calcining at the end of the steps of support preparation and / or introduction of at least one hydro-dehydrogenation element.

[0065] More particularly, the catalyst is prepared according to a preparation method comprising the following steps: a) Preparing zeolite Y having the specific crystallographic characteristics claimed according to the above method, b) In the case where zeolite β is present in the catalyst formulation according to the invention, prepare zeolite β, c) Mix with a porous inorganic matrix and shape to obtain a support, d) Introduce at least one hydrodehydrogenation element onto the support by at least one of the following methods: - Add at least one precursor of the element during the shaping process to introduce at least a part of the element, - Impregnate the support with at least one precursor of the hydrodehydrogenation element, - Optionally, dry and / or calcine the product obtained at the end of each of preparation steps a), b), c) or d).

[0066] The support can be advantageously shaped by any technique known to those skilled in the art. Shaping can be carried out, for example, by extrusion, by granulation, by the dropping (oil drop) method, by granulation on a rotating disk or by any other method known to those skilled in the art.

[0067] The support is preferably shaped into particles of various shapes and sizes. They are generally used in the form of cylindrical pellets or multi-lobed pellets, such as trilobal, tetralobal or multi-lobed pellets, in straight or twisted form, but can optionally be manufactured and used in the form of crushed powder, ingots, rings, beads or wheels. However, the catalyst is advantageously in the form of pellets having a diameter between 0.5 and 5 mm, and more particularly between 0.7 and 3 mm, and even more particularly between 1.0 and 2.5 mm. The shape is cylindrical (which can be hollow or non-hollow), twisted cylindrical, multi-lobed (e.g. 2, 3, 4 or 5 lobes) or ring. Any other shape can be used.

[0068] One of the preferred shaping methods consists in co-kneading the zeolite with a binder (preferably alumina) in the form of a wet gel for several tens of minutes, preferably 10 to 40 minutes, and then passing the paste thus obtained through a die to form pellets having a diameter preferably between 0.5 and 5 mm.

[0069] According to another preferred shaping method, the zeolite can be introduced during the synthesis of the porous inorganic matrix. For example, according to this preferred embodiment of the invention, zeolites Y and β are added during the synthesis of a porous inorganic matrix, such as a silica-alumina matrix: in this case, the zeolite can be advantageously added to a mixture consisting of an alumina compound in an acidic medium and a completely soluble silica compound.

[0070] Group VIB and / or Group VIII elements can optionally be introduced during the shaping step by adding at least one compound of the element in order to introduce at least a part of the element.

[0071] The introduction of at least one hydrogenation-dehydrogenation element may advantageously be accompanied by the introduction of at least one promoter element selected from phosphorus, boron, silicon, and preferably phosphorus, and optionally by the introduction of Group VIIA and / or Group VB elements. The shaped solid is optionally dried at a temperature between 60 °C and 250 °C and optionally calcined at a temperature between 250 °C and 800 °C for a time of 30 minutes to 6 hours.

[0072] The step of introducing at least one hydrogenation-dehydrogenation element is advantageously carried out by methods known to those skilled in the art, in particular by one or more operations of impregnating a shaped and calcined or dried, and preferably calcined, support with a solution containing a precursor of a Group VIB and / or Group VIII element, optionally a precursor of at least one promoter element, and optionally a precursor of at least one Group VIIA and / or Group VB element.

[0073] Preferably, step d) is carried out by the method of dry impregnation with a solution containing a precursor of a hydrogenation / dehydrogenation functionality (i.e., a Group VIB and / or Group VIII element), optionally followed by a drying step, and preferably without a calcination step.

[0074] In the case where the catalyst of the present invention contains a Group VIII non-noble metal, the Group VIII metal is preferably introduced after or simultaneously with the Group VIB metal by one or more operations of impregnating a shaped and calcined support.

[0075] After the introduction of at least one hydrogenation-dehydrogenation element, it may optionally be dried at a temperature between 60 °C and 250 °C and optionally calcined at a temperature between 250 °C and 800 °C.

[0076] Sources of molybdenum and tungsten are advantageously selected from oxides and hydroxides, molybdic and tungstic acids and their salts, especially ammonium salts such as ammonium molybdate, ammonium heptamolybdate, and ammonium tungstate, phosphomolybdic acid, phosphotungstic acid and their salts, silicomolybdic acid, silicotungstic acid and their salts. Oxides and ammonium salts such as ammonium molybdate, ammonium heptamolybdate, and ammonium tungstate are preferably used.

[0077] Sources of Group VIII non-noble elements that can be used are known to those skilled in the art. For example, for non-noble metals, nitrates, sulfates, hydroxides, phosphates, halides such as chlorides, bromides, and fluorides, carboxylates such as acetates and carbonates can be used.

[0078] A preferred source of phosphorus is orthophosphoric acid H3PO4, but its salts and esters such as ammonium phosphate are also suitable. Phosphorus can be introduced, for example, in the form of a mixture of phosphoric acid and nitrogen-containing basic organic compounds such as ammonia water, primary and secondary amines, cyclic amines, compounds of the pyridine and quinoline families, and compounds of the pyrrole family. Phosphotungstic acid or molybdotungstic acid can be used.

[0079] Without limiting the scope of the present invention, the phosphorus content is adjusted to form mixed compounds in solution and / or on a support, such as tungsten-phosphorus or molybdenum-tungsten-phosphorus. These mixed compounds can be heteropolyanions. These compounds can be, for example, Anderson heteropolyanions.

[0080] The boron source can be boric acid, preferably orthoboric acid H3BO3, ammonium diborate or ammonium pentaborate, boron oxide or borate ester. Boron can be introduced, for example, in the form of a mixture of boric acid, aqueous hydrogen peroxide solution and nitrogen-containing basic organic compounds such as ammonia water, primary and secondary amines, cyclic amines, compounds of the pyridine and quinoline families, and compounds of the pyrrole family. Boron can be introduced, for example, from a solution of boric acid in a water / alcohol mixture.

[0081] Many silicon sources can be used. Thus, tetraethyl orthosilicate Si(OEt)4, siloxanes, polysiloxanes, organosilicons, organosilicon emulsions, halosilicates, such as ammonium fluorosilicate (NH4)2SiF6 or sodium fluorosilicate Na2SiF6 can be used. It is also possible to advantageously use silicomolybdic acid and its salts, silicotungstic acid and its salts. Silicon can be added, for example, by impregnation with tetraethyl orthosilicate dissolved in a water / alcohol mixture. Silicon can be added, for example, by impregnation with an organosilicon or a silicon compound of the silicic acid type suspended in water.

[0082] Sources of group VB elements that can be used are well known to those skilled in the art. For example, in the case of niobium sources, oxides such as niobium pentoxide Nb2O5, niobic acid Nb2O5·H2O, niobium hydroxide and polyoxoniobates, niobium alkoxides of the formula Nb(OR1)3 (where R1 is an alkyl group), niobium oxalate NbO(HC2O4)5 or ammonium niobate can be used. Ammonium niobium oxalate or ammonium niobate is preferably used.

[0083] Sources of group VIIA elements that can be used are well known to those skilled in the art. For example, the fluoride anion can be introduced in the form of hydrofluoric acid or its salts. These salts are formed by alkali metals, ammonium or organic compounds. In the latter case, the salt is advantageously formed in the reaction mixture by the reaction between an organic compound and hydrofluoric acid. Hydrolyzable compounds that can release fluoride anions in water, such as ammonium fluorosilicate (NH4)2SiF6, silicon tetrafluoride SiF4 or sodium fluorodecanoate Na2SiF6 can also be used. Fluorine can be introduced, for example, by impregnation with an aqueous solution of hydrofluoric acid or ammonium fluoride.

[0084] Hydrocracking process The catalyst according to the present invention is then advantageously used in a hydrocracking process, particularly for the production of naphtha. The catalyst used in a hydrocracking process, such as the process according to the present invention, can advantageously be in the sulfide form. The group VIB metal and / or the group VIII non-noble metal of the catalyst are thus present in the sulfide form.

[0085] The catalysts used in the process according to the invention are then advantageously pre-treated by sulfidation to convert at least part of the metal species into the sulfide form before they come into contact with the feedstock to be treated. This activation treatment by sulfidation is well known to those skilled in the art and can be carried out in situ (i.e., in the reactor) or ex situ by any method already described in the literature.

[0086] Conventional sulfidation methods known to those skilled in the art consist in heating the catalyst generally between 150 °C and 800 °C, preferably between 250 °C and 600 °C, in the presence of hydrogen sulfide (pure or, for example, under a stream of a hydrogen - hydrogen sulfide mixture) in a fluidized bed reaction zone.

[0087] Another subject of the invention is a process for hydrocracking at least one hydrocarbon feedstock, preferably in liquid form, in the presence of a catalyst according to the invention at a temperature between 200 °C and 480 °C, at a total pressure between 1 MPa and 25 MPa, at a hydrogen gas volume / hydrocarbon feedstock volume ratio between 80 and 5000 l / l and at a space velocity (HSV) defined by the ratio of the volume flow rate of the hydrocarbon feedstock (which is preferably liquid) to the volume of catalyst charged to the reactor between 0.1 and 50 h -1 -1, the compounds of which at least 50% by weight have an initial boiling point above 300 °C and a final boiling point below 650 °C.

[0088] Advantageously, the catalyst according to the invention is used in the hydrocracking process according to the invention after a pretreatment section containing one or more hydrotreating catalysts, which can be any catalyst known to those skilled in the art and which is capable of reducing the content of certain contaminants (see below) such as nitrogen, sulfur or metals in the feedstock. The operating conditions (HSV, temperature, pressure, hydrogen flow rate, liquid, reaction configuration, etc.) of this pretreatment section can be varied and adapted according to the knowledge of those skilled in the art.

[0089] Feedstock Very different feedstocks can be treated by the hydrocracking process according to the invention. The feedstock used in the hydrocracking process according to the invention is a hydrocarbon feedstock, of which at least 50% by weight of the compounds have an initial boiling point above 300 °C and a final boiling point below 650 °C, preferably at least 60% by weight, preferably at least 75% by weight, and more preferably at least 80% by weight of the compounds have an initial boiling point above 300 °C and a final boiling point below 650 °C.

[0090] The feedstock is advantageously selected from LCO (light cycle oil, light gas oil obtained from a fluid catalytic cracking unit), atmospheric distillates, vacuum distillates (such as gas oils obtained from the direct distillation of crude oil or from conversion units such as FCC, coking or visbreaking units), feedstocks originating from units for the extraction of aromatics from lubricant base oils or obtained from the solvent dewaxing of lubricant base oils, distillates from fixed-bed or fluidized-bed desulfurization or hydroconversion processes of AR (atmospheric residue) and / or VR (vacuum residue) and / or deasphalted oil, and deasphalted oil or paraffins obtained from a Fischer-Tropsch process, used alone or as a mixture. Mention may be made of feedstocks of renewable origin (such as vegetable oils, animal fats, oils from the hydrothermal conversion or pyrolysis of lignocellulosic biomass) and plastic pyrolysis oils. The above list is not restrictive. The feedstock preferably has a boiling point T5 higher than 300 °C, preferably higher than 340 °C, i.e. 95% of the compounds present in the feedstock have a boiling point higher than 300 °C and preferably higher than 340 °C.

[0091] The nitrogen content of the feedstock treated in the process according to the invention is advantageously greater than 500 ppm by weight, preferably between 500 and 10,000 ppm by weight, more preferably between 700 and 4000 ppm by weight, and even more preferably between 1000 and 4000 ppm by weight. The sulfur content of the feedstock treated in the process according to the invention is advantageously 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.

[0092] The feedstock may optionally contain metals. The cumulative nickel and vanadium content of the feedstock treated in the process according to the invention is preferably less than 1 ppm by weight.

[0093] The feedstock may optionally contain asphaltenes. The asphaltene content is generally less than 3000 ppm by weight, preferably less than 1000 ppm by weight, and even more preferably less than 200 ppm by weight.

[0094] Advantageously, when the catalyst according to the invention is used after the hydrotreating section as described above, the content of nitrogen, sulfur, metals or asphaltenes in the liquid in the process according to the invention using the catalyst according to the invention is reduced. Preferably, the organic nitrogen content in the feedstock treated in the hydrocracking process according to the invention is between 0 and 200 ppm, preferably between 0 and 50 ppm, and even more preferably between 0 and 30 ppm after hydrotreating. The sulfur content is preferably less than 1000 ppm, and the asphaltene content is preferably less than 200 ppm, while the metal (Ni or V) content is less than 1 ppm.

[0095] The hydrocracking process according to the present invention may include a fractionation step between the pretreatment of the feedstock and the (one or more) hydrocracking reactors using the catalyst according to the present invention. In a preferred case where the hydrocracking process is carried out without (gas and liquid) fractionation between the pretreatment and the (one or more) hydrocracking reactors using the catalyst according to the present invention, the nitrogen and sulfur removed from the liquid after pretreatment are injected into the (one or more) reactors containing the catalyst according to the present invention in the form of NH3 and H2S.

[0096] According to the present invention, the hydrocracking process of the hydrocarbon feedstock according to the present invention is carried out at a temperature between 200 °C and 480 °C, at a total pressure between 1 MPa and 25 MPa, at a hydrogen gas volume / hydrocarbon feedstock volume ratio between 80 and 5000 l / l, and at a space velocity (HSV) defined by the ratio of the volume flow rate of the hydrocarbon feedstock to the volume of the catalyst charged to the reactor between 0.1 and 50 h -1 between.

[0097] Preferably, the hydrocracking process according to the present invention is carried out in the presence of hydrogen, at a temperature between 250 °C and 480 °C, preferably between 320 °C and 450 °C, very preferably between 330 °C and 435 °C, at a pressure between 2 and 25 MPa, and very preferably between 3 and 20 MPa, at a space velocity between 0.1 and 20 h -1 between, preferably between 0.1 and 6 h -1 between, preferably between 0.2 and 3 h -1 between, and the amount of hydrogen introduced is such that the volume ratio of hydrogen liters to hydrocarbon liters is between 100 and 2000 l / l.

[0098] The process can be carried out in one or two steps depending on the degree of conversion of the target feedstock, with or without recycle of the unconverted fraction. The catalyst according to the present invention can be used, without limitation, alone or in combination with another hydrocracking catalyst in one or both steps of the hydrocracking process.

[0099] These operating conditions used in the process according to the present invention generally enable a single-pass conversion of greater than 15 wt%, and more preferably between 20 and 100 wt%, to products having a boiling point below 340 °C, and even better below 370 °C.

[0100] The examples illustrate the invention without limiting its scope. Examples

[0101] Example 1 - Preparation of Comparative Catalyst A The support of Catalyst A was prepared by kneading-extrusion molding of 70 wt% of zeolite USY with a lattice parameter of 24.53 Å, a silica / alumina molar ratio (SAR) of 9, a specific surface area of 925 m 2 / g measured by nitrogen physical adsorption according to the BET method, a micropore volume of 0.32 ml / g measured by nitrogen adsorption, a mesopore volume of 0.12 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 852 µmol / g in the presence of commercial boehmite (Pural SB3, Sasol). The resulting pellets were dried at 80 °C and then calcined at 600 °C in humid air (5 wt% water / kg dry air). The calcined support contained, on a dry basis, 70 wt% of zeolite and 30 wt% of alumina.

[0102] Catalyst A was prepared by dry impregnation of the obtained support with an aqueous solution containing elements Ni and Mo. This solution was obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of precursors in the solution was adjusted according to the target concentration on the final catalyst. After dry impregnation, the catalyst was dried in air at 120 °C.

[0103] The mass percentages in the catalyst were, on a dry basis, 15.1 wt% of molybdenum (in the form of MoO3) and 3.3 wt% of nickel (in the form of NiO).

[0104] Example 2 - Preparation of Comparative Catalyst B The support of Catalyst B was prepared by kneading-extrusion molding of 70 wt% of zeolite USY with a lattice parameter of 24.48 Å, a silica / alumina molar ratio (SAR) of 6, a specific surface area of 827 m 2 / g measured by nitrogen physical adsorption according to the BET method, a micropore volume of 0.27 ml / g measured by nitrogen adsorption, a mesopore volume of 0.16 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 614 µmol / g in the presence of commercial boehmite (Pural SB3, Sasol). The resulting pellets were dried at 80 °C and then calcined at 600 °C in humid air (5 wt% water / kg dry air). The calcined support contained, on a dry basis, 70 wt% of zeolite USY and 30 wt% of alumina.

[0105] Catalyst B was prepared by dry impregnation of the obtained support with an aqueous solution containing elements Ni and Mo. This solution was obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of precursors in the solution was adjusted according to the target concentration on the final catalyst. After dry impregnation, the catalyst was dried in air at 120 °C.

[0106] The mass percentages in the catalyst are as follows: on a dry basis, 15.1 wt% of molybdenum (in the form of MoO3) and 3.3 wt% of nickel (in the form of NiO).

[0107] Example 3 - Preparation of Comparative Catalyst C The support of Catalyst C was prepared by kneading-extrusion molding of 70 wt% of zeolite USY having a lattice parameter of 24.48 Å, a silica / alumina molar ratio (SAR) of 6, a specific surface area of 847 m 2 / g measured by nitrogen physisorption according to the BET method, a micropore volume of 0.29 ml / g measured by nitrogen adsorption, a mesopore volume of 0.11 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 420 µmol / g in the presence of commercial boehmite (Pural SB3, Sasol). The obtained pellets were dried at 80 °C and then calcined at 600 °C in humid air (5 wt% water / kg dry air). The calcined support contained, on a dry basis, 70 wt% of zeolite USY and 30 wt% of alumina.

[0108] Catalyst C was prepared by dry impregnation of the obtained support with an aqueous solution containing elements Ni and Mo. This solution was obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of precursors in the solution was adjusted according to the target concentration on the final catalyst. After dry impregnation, the catalyst was dried in air at 120 °C.

[0109] The mass percentages in the catalyst are as follows: on a dry basis, 15.1 wt% of molybdenum (in the form of MoO3) and 3.3 wt% of nickel (in the form of NiO).

[0110] Example 4 - Preparation of Catalyst D According to the Invention The support of Catalyst D was prepared by kneading-extrusion molding of 70 wt% of zeolite USY having a lattice parameter of 24.47 Å, a silica / alumina molar ratio (SAR) of 9, a specific surface area of 931 m 2 / g measured by nitrogen physisorption according to the BET method, a micropore volume of 0.31 ml / g measured by nitrogen adsorption, a mesopore volume of 0.24 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 698 µmol / g in the presence of commercial boehmite Pural SB3.

[0111] The obtained pellets were dried at 80 °C and then calcined at 600 °C in humid air (5 wt% water / kg dry air). The calcined support contained, on a dry basis, 70 wt% of zeolite USY and 30 wt% of alumina.

[0112] Catalyst D is prepared by dry impregnation of a carrier with an aqueous solution containing elements Ni and Mo. This solution is obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of the precursors in the solution is adjusted according to the target concentration on the final catalyst. After dry impregnation, the catalyst is dried in air at 120 °C.

[0113] The mass percentages in the catalyst are respectively: on a dry basis, 15.0 wt% of molybdenum (in the form of MoO3) and 3.2 wt% of nickel (in the form of NiO).

[0114] Example 5 - Preparation of Catalyst E according to the Invention The support for Catalyst E is prepared by kneading-extrusion molding of 60 wt% of zeolite USY with a lattice parameter of 24.47 Å, a silica / alumina molar ratio (SAR) of 9, a specific surface area of 931 m 2 / g measured by nitrogen physisorption according to the BET method, a micropore volume of 0.31 ml / g measured by nitrogen adsorption, a mesopore volume of 0.24 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 698 μmol / g, and 10 wt% of commercial zeolite β (CP814E, Zeolyst) with a SiO2 / Al2O3 molar ratio of 25 and a specific surface area of 670 m 2 / g measured by nitrogen physisorption according to the BET method, in the presence of commercial boehmite (Pural SB3, Sasol).

[0115] The obtained pellets are dried at 80 °C and then calcined in humid air (5 wt% water / kg dry air) at 600 °C. The calcined support contains, on a dry basis, 60 wt% of zeolite USY, 10 wt% of zeolite β, and 30 wt% of alumina, i.e., the Y / β weight ratio in this catalyst = 6. After dry impregnation, the catalyst is dried in air at 120 °C.

[0116] Catalyst E is prepared by dry impregnation of the obtained support with an aqueous solution containing elements Ni and Mo. This solution is obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of the precursors in the solution is adjusted according to the target concentration on the final catalyst.

[0117] The mass percentages in the catalyst are respectively: on a dry basis, 15.0 wt% of molybdenum (in the form of MoO3) and 3.2 wt% of nickel (in the form of NiO).

[0118] Example 6 - Preparation of Comparative Catalyst F according to Shell Patent US7611689 The support of catalyst F was prepared by kneading-extrusion molding in the presence of commercial boehmite (Pural SB3, Sasol) using zeolite USY with a lattice parameter of 24.46 Å, a silica / alumina molar ratio (SAR) of 8.1, a specific surface area of 810 m 2 / g measured by nitrogen physisorption according to the BET method, a micropore volume of 0.27 ml / g measured by nitrogen adsorption, a mesopore volume of 0.14 ml / g measured by nitrogen adsorption, and a Bronsted acidity of 510 μmol / g. The resulting pellets were dried at 80 °C and then calcined at 600 °C in humid air (5 wt% water / kg dry air). The calcined support contained, on a dry basis, 70 wt% zeolite USY and 30 wt% alumina.

[0119] Catalyst F was prepared by dry impregnation of the obtained support with an aqueous solution containing the elements Ni and Mo. This solution was obtained by dissolving the following precursors in water: nickel nitrate and ammonium heptamolybdate. The amount of precursors in the solution was adjusted according to the target concentration on the final catalyst.

[0120] The mass percentages in the catalyst were, on a dry basis, 15.0 wt% molybdenum (in the form of MoO3) and 3.2 wt% nickel (in the form of NiO).

[0121] Example 7 The performance of the above catalysts was evaluated in the single-step hydrocracking of a feedstock containing a vacuum gas oil fraction and gas oil in an isothermal pilot test unit using a downflow configuration.

[0122] This test feedstock was subjected to hydrotreating (HDT). After this hydrotreating step, the test feedstock had a density of 0.8755 g / ml at 15 °C, a residual nitrogen content of 23 wt ppm, and a residual sulfur content of 16 wt ppm. The initial point of the simulated distillation of this hydrotreated test feedstock was 163.3 °C, and the end point was 578.7 °C. The 50 wt% point of the simulated distillation was 391.7 °C. To simulate the partial pressures of hydrogen sulfide and ammonia generated in the HDT step of the process, DMDS and aniline were added to the test feedstock, respectively, to obtain 8820 wt ppm sulfur and 1900 wt ppm nitrogen in the final additive-containing feedstock.

[0123] Each catalyst was evaluated separately and sulfided under SRGO (straight-run gas oil) feedstock (i.e., gas oil produced by direct distillation of crude oil with 4 wt% dimethyl sulfide (DMDS) and 2 wt% aniline added) before the hydrocracking test. The sulfiding was carried out at 2h -1at an HSV (HSV = hourly space velocity) of, a H2 / feedstock volume ratio of 1000 Nl / l, a total pressure of 140 bar (i.e., 14.0 MPa), and a holding temperature of 350 °C for 6 hours.

[0124] After sulfidation, the operating conditions were adjusted to those for the hydrocracking test: 1.5 h -1 of HSV, a H2 / feedstock volume ratio of 1000 Nl / l, and a total pressure of 140 bar (i.e., 14.0 MPa). The temperature of the reactor was adjusted so that the target was a net conversion of 65 wt% of the 216 °C+ fraction of the feedstock after 150 hours.

[0125] The net conversion is defined as the yield of the fraction (or fraction) with a boiling point below 216 °C minus the yield of the fraction with a boiling point below 216 °C present in the test feedstock.

[0126] The performance of the catalyst was compared with that of a reference catalyst D and reported in Table 1. The relative activity in degrees Celsius (°C) was obtained from the temperature difference between the catalyst to be evaluated and the reference catalyst D to achieve a net conversion of 65%. Similarly, the relative yield of the 68 - 216 °C fraction was taken as the difference between the yields obtained at a net conversion of 65 wt% of the 216 °C+ fraction. A positive value indicates higher activity or yield.

[0127] Table 1 Table 1. Characterization and performance positioning of catalysts A to F.

[0128] The results reported in Table 1 show that the catalyst D according to the invention, which consists of zeolite USY with a lattice parameter of 24.47 Å, a specific surface area of 931 m 2 / g, a micropore volume of 0.31 ml / g, and an acidity of 698 μmol / g, exhibits a systematic gain in activity compared to the comparative catalysts B and C without any decrease in yield, and a gain in selectivity for the naphtha fraction compared to the comparative catalyst A without any decrease in activity.

[0129] More particularly, it was found that the comparative catalyst A, which has the acidity according to the invention but does not conform to the lattice parameter of the invention, shows a significant decrease in the yield of the naphtha fraction compared to the catalyst D according to the invention.

[0130] Furthermore, the addition of zeolite β to zeolite USY according to the invention demonstrated that in the presence of zeolite β, the zeolite USY used in the catalyst according to the invention also achieves high performance in both activity and selectivity for the naphtha fraction, which is higher than those obtained with the catalysts of the prior art.

[0131] The comparative catalyst F, which has an acidity, micropore volume, and SBET that do not conform to the present invention, has a lower activity than catalyst D according to the present invention.

Claims

1. A hydrocracking catalyst comprising at least one hydro-dehydrogenation element selected from elements of Group VIB and non-noble elements of Group VIII of the Periodic Table, either alone or as a mixture, and a support comprising at least one porous inorganic matrix, a zeolite Y having an initial lattice parameter a0 of the unit cell between 24.40 Å and 24.52 Å, a BET specific surface area between 850 and 1020 m 2 / g, a micropore volume greater than 0.28 ml / g measured by nitrogen adsorption, and a Bronsted acidity greater than 600 μmol / g.

2. The catalyst according to claim 1, wherein the Group VIII element is selected from iron, cobalt, nickel, either alone or as a mixture, and is preferably selected from nickel and cobalt. Based on the total weight of the catalyst, the content of the Group VIII element, calculated as the weight of the oxide, is between 0.5% and 8% by weight, preferably between 0.5% and 6% by weight, and very preferably between 1.0% and 4% by weight.

3. The catalyst according to any one of claims 1 and 2, wherein the Group VIB element is selected from tungsten and molybdenum, either alone or as a mixture. Based on the total weight of the catalyst, the content of the Group VIB element, calculated as the weight of the oxide, is between 1% and 30% by weight, preferably between 2% and 25% by weight, very preferably between 5% and 20% by weight, and even more preferably between 5% and 16% by weight.

4. The catalyst according to any one of claims 1 to 3, wherein the zeolite Y has a Bronsted acidity greater than 650 μmol / g, preferably greater than 700 μmol / g, and very preferably greater than 760 μmol / g, and preferably, the zeolite Y has a Bronsted acidity less than 1000 μmol / g.

5. The catalyst according to any one of claims 1 to 4, wherein the initial lattice parameter a0 of the unit cell of the zeolite Y is between 24.40 and 24.51 Å, preferably between 24.43 and 24.51 Å, and very preferably between 24.45 and 24.48 Å.

6. The catalyst according to any one of claims 1 to 5, wherein the zeolite Y has a specific surface area measured by physical adsorption of nitrogen using the BET method in the range of 875 to 995 m 2 / g, and preferably in the range of 900 to 970 m 2 / g.

7. The catalyst according to any one of claims 1 to 6, wherein the zeolite Y has a micropore volume measured by nitrogen adsorption greater than 0.30 ml / g, advantageously greater than 0.31 ml / g, and advantageously less than 0.34 ml / g.

8. The catalyst according to any one of claims 1 to 7, wherein the zeolite Y has a silica / alumina molar ratio (SAR) between 5 and 50, preferably between 5 and 20, and more preferably between 5 and 10.

9. The catalyst according to any one of claims 1 to 8, wherein the zeolite Y has a mesopore volume greater than or equal to 0.18 ml / g, preferably between 0.18 and 0.27 ml / g, preferably between 0.20 and 0.26 ml / g, and very preferably between 0.22 and 0.25 ml / g.

10. The catalyst according to any one of claims 1 to 9, wherein the catalyst further comprises zeolite β.

11. In the presence of a catalyst according to any one of claims 1 to 10, at a temperature between 200 °C and 480 °C, at a total pressure between 1 MPa and 25 MPa, at a hydrogen gas volume / hydrocarbon feedstock volume ratio between 80 and 5000 liters / liter and at a space velocity (HSV) defined by the ratio of the volume flow rate of the hydrocarbon feedstock to the volume of catalyst charged to the reactor between 0.1 and 50 h -1 to hydrocrack at least one hydrocarbon feedstock, at least 50 wt% of the compounds in the hydrocarbon feedstock having an initial boiling point above 300 °C and a final boiling point below 650 °C.

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