Beta / ZSM-5 symbiotic zeolite molecular sieve, hydrocracking catalyst, preparation method and application

Abstract

The invention discloses a Beta / ZSM-5 symbiotic zeolite molecular sieve, a hydrocracking catalyst as well as a preparation method and application of the Beta / ZSM-5 symbiotic zeolite molecular sieve. The Beta / ZSM-5 symbiotic zeolite molecular sieve has a BEA topological structure and an MFI topological structure at the same time, the particle size of the BEA topological structure is 50-500 nm, and the particle size of the MFI topological structure is 3-6 [mu] m; preferably, the ratio of the amount of molecular substance of the Beta / ZSM-5 symbiotic zeolite molecular sieve to the amount of molecular substance of the silicon-aluminum oxide is 25 to 300, preferably 50 to 200. When the hydrocracking catalyst is applied to catalytic diesel hydrocracking reaction, the yield of light aromatic hydrocarbon and benzene as reaction products can be effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydrocracking, and in particular to a Beta / ZSM-5 intergrowth zeolite molecular sieve, a hydrocracking catalyst, a preparation method and an application thereof. Background Art

[0002] As an important by-product of the catalytic cracking unit, catalytic diesel has the characteristics of high total aromatic content, high sulfur and nitrogen content and low cetane number, and is not suitable for processing into automotive diesel. Converting catalytic diesel that has been treated with hydrorefining into high-value-added ethylene cracking materials and light aromatics through hydrocracking is an important means of utilizing catalytic diesel.

[0003] Chinese patent CN105435836A discloses a hydrocracking catalyst and its preparation and application, using ZSM-5 and Beta zeolite molecular sieve as cracking active components, and having a high tetralin conversion rate. Chinese patent CN114433211A discloses a chemical hydrocracking catalyst and its preparation method and application, selecting Beta zeolite and layered MWW zeolite molecular sieve as cracking active components, effectively improving the single-pass conversion rate of raw materials and the yield of light aromatics. Chinese patent CN112570016A discloses a nitrogen-resistant aromatic hydrocracking catalyst and its preparation method and application, selecting Beta zeolite molecular sieve with high strong acid content as cracking active component, which can achieve high conversion rate and long-term stability of raw materials.

[0004] Although the conventional Beta zeolite molecular sieve-based hydrocracking catalyst has a good single-pass conversion rate, its light aromatics yield is still low, especially the benzene yield is not high. Therefore, there is a need for a hydrocracking catalyst with a higher light aromatics and benzene yield. Summary of the invention

[0005] In order to solve the problem of low light aromatics yield, especially low benzene yield, of the Beta zeolite molecular sieve-based catalytic diesel hydrocracking catalyst in the prior art, the present invention provides a Beta / ZSM-5 intergrowth zeolite molecular sieve, a hydrocracking catalyst, a preparation method and an application. The catalyst is applied to the catalytic diesel hydrocracking reaction to effectively improve the yield of light aromatics and benzene of the reaction products.

[0006] One of the objects of the present invention is to provide a Beta / ZSM-5 symbiotic zeolite molecular sieve having both BEA and MFI topological structures, wherein the particle size of the BEA topological structure is 50-500nm, and the particle size of the MFI topological structure is 3-6μm; preferably, the amount ratio of silicon aluminum oxide molecules in the Beta / ZSM-5 symbiotic zeolite molecular sieve is 25-300, preferably 50-200.

[0007] In a preferred embodiment of the present invention,

[0008] The X-ray diffraction spectrum of the Beta / ZSM-5 intergrowth zeolite molecular sieve simultaneously exhibits characteristic diffraction peaks of the Beta zeolite molecular sieve and characteristic diffraction peaks of the ZSM-5 zeolite molecular sieve; preferably, the X-ray diffraction spectrum of the Beta / ZSM-5 intergrowth zeolite molecular sieve Figure 2 θ has characteristic diffraction peaks of Beta molecular sieve at 7.6° and 22.4°, and / or, characteristic diffraction peaks of ZSM-5 molecular sieve appear at 7.9°, 8.9° and 22.5-25°; and / or,

[0009] The content of ZSM-5 zeolite molecular sieve in the Beta / ZSM-5 intergrowth zeolite molecular sieve is 5-80%, preferably 20-50%, more preferably 30-40%, and the content of Beta zeolite molecular sieve is 20-95%, preferably 50-80%, more preferably 60-70%.

[0010] The Beta / ZSM-5 intergrowth zeolite molecular sieve has both the twelve-membered ring pores of the Beta molecular sieve and the ten-membered ring pores of the ZSM-5 molecular sieve.

[0011] In a preferred embodiment of the present invention,

[0012] The Beta / ZSM-5 intergrown zeolite molecular sieve is obtained by a one-step hydrothermal synthesis. Preferably, the Beta / ZSM-5 intergrown zeolite molecular sieve is obtained by a preparation method comprising aging a mixture containing a silicon source, an aluminum source, a template and a base, followed by a crystallization step.

[0013] The second object of the present invention is to provide a method for preparing the Beta / ZSM-5 symbiotic zeolite molecular sieve of one of the objects of the present invention, wherein the Beta / ZSM-5 symbiotic zeolite molecular sieve is obtained by a one-step hydrothermal synthesis. Preferably, the method for preparing the Beta / ZSM-5 symbiotic zeolite molecular sieve comprises the steps of aging a mixture comprising a silicon source, an aluminum source, a template and a base, and then crystallizing the mixture.

[0014] In a preferred embodiment of the present invention,

[0015] The silicon source is selected from at least one of silica sol, silica gel, water glass, white carbon black, and tetraethyl orthosilicate; and / or,

[0016] The aluminum source is selected from at least one of sodium aluminate, pseudo-boehmite, aluminum nitrate, aluminum sulfate, and aluminum sol; and / or,

[0017] The template agent is selected from tetraethylammonium hydroxide; and / or,

[0018] The base is selected from sodium hydroxide.

[0019] In a preferred embodiment of the present invention,

[0020] The molar ratio of the silicon source, aluminum source, template, water and alkali in the mixture is SiO2:Al2O3:TEAOH:H2O:Na2O=1:(0.0033-0.04):(0.1-0.6):(5-30):(0.01-0.5) based on the oxide ratio, preferably SiO2:Al2O3:TEAOH:H2O:Na2O=1:(0.005-0.02):(0.25-0.55):(5-20):(0.02-0.3).

[0021] In a preferred embodiment of the present invention,

[0022] The aging temperature is 20-35°C; and / or, the aging time is more than 2 hours, preferably 4-8 hours; and / or,

[0023] The crystallization temperature is 150-180° C.; and / or the crystallization time is 3-7 days, preferably 4-5 days.

[0024] In a preferred embodiment of the present invention,

[0025] The preparation method of the Beta / ZSM-5 intergrowth zeolite molecular sieve further comprises the steps of solid-liquid separation of the crystallized mixture, and washing, drying and calcining the solid product; preferably,

[0026] The drying temperature is 100-120° C.; and / or the roasting temperature is 500-600° C.; and / or the roasting time is 4-6 hours.

[0027] The preparation method of the Beta / ZSM-5 intergrowth zeolite molecular sieve of the present invention can adopt the following specific technical scheme:

[0028] (1) mixing components including a silicon source, an aluminum source, tetraethylammonium hydroxide and sodium hydroxide and aging them at 20-35° C. for more than 2 hours;

[0029] (2) crystallizing the aged mixture at 150-180° C. for 3-7 days;

[0030] (3) After crystallization, the mixture is separated from the solid and liquid, washed with deionized water, and the solid product is dried at 100-120° C. and calcined at 500-600° C. for 4-6 h to obtain the Beta / ZSM-5 intergrowth zeolite molecular sieve.

[0031] The third object of the present invention is to provide a catalytic diesel hydrocracking catalyst comprising the following components:

[0032] a) Beta / ZSM-5 intergrowth zeolite molecular sieve; b) metal active component; c) binder;

[0033] Preferably, the above-mentioned Beta / ZSM-5 intergrown zeolite molecular sieve is selected from at least one of the Beta / ZSM-5 intergrown zeolite molecular sieve according to one of the purposes of the present invention and the Beta / ZSM-5 intergrown zeolite molecular sieve prepared according to the second purpose of the present invention; more preferably, the Beta / ZSM-5 intergrown zeolite molecular sieve is a hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve; further preferably, based on the NH3-TPD result, the ratio of the amount of medium-strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve is (0.2-20):1, preferably (1-5):1.

[0034] The NH3-TPD characterization of the hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve has both a medium-strong acid desorption peak of the Beta molecular sieve at 300-400°C and a strong acid desorption peak of the ZSM-5 at 400-500°C.

[0035] In the present invention, the Beta / ZSM-5 intergrown zeolite molecular sieve can be converted into a hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve by conventional technical means in the prior art. In the present invention, the sodium-type Beta / ZSM-5 intergrown zeolite molecular sieve is preferably exchanged with 0.1-10M ammonium chloride or ammonium nitrate solution at a solid-liquid ratio of 1:(10-30) and 50-95°C for 1-10h by stirring, and then calcined at 400-600°C for 1-10h. The above operation is repeated 1-3 times to obtain a hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve.

[0036] In a preferred embodiment of the present invention,

[0037] The metal active component includes at least one of Group VIII metals and Group VIII metal sulfides and at least one of Group VIB metal oxides and Group VIB metal sulfides, and preferably includes at least one of Group VIII metal-Group VIB metal oxide, Group VIII metal sulfide-Group VIB metal sulfide, and Group VIII metal sulfide-Group VIB metal oxide-Group VIB metal sulfide.

[0038] In a preferred embodiment of the present invention,

[0039] The Group VIII metal includes at least one of platinum, palladium, ruthenium, cobalt, nickel and iridium; and / or,

[0040] The VIB group metal oxide includes at least one of molybdenum and tungsten oxides; preferably at least one of molybdenum dioxide, molybdenum trioxide, tungsten dioxide, and tungsten trioxide; and / or,

[0041] The Group VIII metal sulfide comprises at least one of sulfides of iron, cobalt and nickel; and / or,

[0042] The VIB group metal sulfide includes at least one of molybdenum disulfide and tungsten disulfide.

[0043] In a preferred embodiment of the present invention,

[0044] The binder includes at least one of aluminum oxide, silicon oxide, silicon oxide-aluminum oxide composite, and amorphous silicon aluminum.

[0045] In a preferred embodiment of the present invention,

[0046] In terms of mass percentage,

[0047] The mass of the Beta / ZSM-5 intergrowth zeolite molecular sieve accounts for 5-80wt% of the mass of the catalyst, preferably 20-75wt%, more preferably 30-70wt%; and / or,

[0048] The metal active component accounts for 3-35wt% of the catalyst mass, preferably 5-23wt%; and / or,

[0049] The balance is binder.

[0050] In a preferred embodiment of the present invention,

[0051] In terms of mass percentage,

[0052] The Group VIII metal and / or Group VIII metal sulfide accounts for 0.01-10 wt %, preferably 0.5-8 wt % of the catalyst mass; and / or,

[0053] The VIB Group metal oxide and / or sulfide accounts for 3-25 wt %, preferably 5-15 wt % of the catalyst mass.

[0054] The fourth object of the present invention is to provide a method for preparing the catalytic diesel hydrocracking catalyst of the third object of the present invention, comprising loading the metal active component on a carrier comprising Beta / ZSM-5 intergrown zeolite molecular sieve and a binder, and then reducing and / or sulfurizing to obtain the catalytic diesel hydrocracking catalyst.

[0055] The catalytic diesel hydrocracking catalyst described in the present invention can be prepared by any method for preparing catalysts in the art, without special limitation. For example, the preparation of the catalyst described in the present invention can include the steps of molding a catalyst carrier comprising the Beta / ZSM-5 co-existing zeolite molecular sieve and a binder, loading the metal active component compound, and then drying and calcining to obtain a catalyst precursor, and reducing and / or sulfurizing the catalyst precursor. The carrier molding method can be carried out by the usual methods of extrusion, rolling ball or oil column molding in the art; the loading of the metal active component can be carried out by the usual methods of co-precipitation, co-gelation, kneading, ion exchange or impregnation of metal and catalyst carrier in the art. Preferably, the following specific steps can be included:

[0056] 1) kneading and extruding the components including the Beta / ZSM-5 intergrowth zeolite molecular sieve and the binder, drying and then calcining in an air atmosphere at 500-600° C. to obtain a catalyst carrier;

[0057] 2) preparing a metal compound aqueous solution with metal components including at least one of the Group VIII metal compounds and at least one of the Group VIB metal compounds; impregnating the above obtained catalyst carrier by an equal volume impregnation method, and calcining in an air atmosphere at 450-580° C. after drying to obtain a catalyst precursor;

[0058] 3) reducing the obtained catalyst precursor under hydrogen conditions at 400-500° C. to obtain the catalyst;

[0059] Alternatively, the obtained catalyst precursor is sulfurized under a sulfurization condition of 280-360° C. to obtain the catalyst;

[0060] Alternatively, the obtained catalyst precursor is reduced with hydrogen and then sulfided to obtain the catalyst.

[0061] The fifth object of the present invention is to provide a catalytic diesel hydrocracking catalyst according to the third object of the present invention or a catalytic diesel hydrocracking catalyst obtained by the preparation method according to the fourth object of the present invention, and use it in a hydrogenation catalytic diesel hydrocracking reaction.

[0062] In a preferred embodiment of the present invention,

[0063] The application comprises the step of contacting the catalytic diesel hydrocracking catalyst with hydrogenated catalytic diesel under hydrocracking conditions; preferably, the feedstock oil suitable for the catalytic diesel hydrocracking catalyst of the present invention in the hydrocracking reaction is hydrogenated catalytic diesel that has been treated with hydrorefining, the catalytic diesel T95 is ≤360°C, preferably ≤345°C, and the total nitrogen content of the hydrogenated catalytic diesel obtained after hydrorefining is ≤15ppm, preferably the total nitrogen content is ≤10ppm.

[0064] In a preferred embodiment of the present invention,

[0065] The process conditions of the hydrocracking reaction include:

[0066] Reactor inlet temperature 280-450°C, preferably 310-430°C, more preferably 350-410°C; and / or,

[0067] Hydrogen partial pressure 5-10 MPa, preferably 5-9 MPa, more preferably 6-8 MPa; and / or,

[0068] Mass airspeed 0.5-2.0h -1 , preferably 0.6-1.5h -1 , more preferably 0.8-1.2h -1 and / or,

[0069] The volume ratio of fresh hydrogen to hydrogenated catalytic diesel is 400-1000, preferably 500-800, more preferably 500-600; and / or,

[0070] The volume ratio of hydrogen to oil of the mixed hydrogen and hydrogenated catalytic diesel is 1000-5000, preferably 2000-4000, more preferably 2000-3000.

[0071] In a preferred embodiment of the present invention,

[0072] The hydrocracking catalyst of the present invention is used to carry out the reaction under the above hydrocracking reaction conditions, and the hydrocracking reaction product satisfies: C 11+ The component single-pass conversion rate is greater than 85%, preferably greater than 90%; and / or, C 6-10 The aromatics yield is ≥35wt%, preferably ≥38wt%, more preferably ≥40wt%; and / or the benzene yield is ≥2.6wt%, preferably ≥3.0wt%, more preferably ≥3.2wt%.

[0073] Beneficial effects of the present invention:

[0074] The Beta / ZSM-5 intergrowth zeolite molecular sieve and catalytic diesel hydrocracking catalyst of the present invention can be applied to the hydrocracking reaction of hydrocatalytic diesel, and realize the lightening process of converting hydrocatalytic diesel into high value-added chemical products such as light aromatics and ethylene cracking raw materials. The present invention can effectively improve the problem of low light aromatics selectivity of conventional Beta zeolite molecular sieve-based catalytic diesel hydrocracking catalysts, and obtain high light aromatics and benzene yields. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 The XRD spectrum of the Beta / ZSM-5 intergrowth zeolite molecular sieve in Example 1 of the present invention;

[0076] Figure 2 This is a SEM photo of the Beta / ZSM-5 intergrowth zeolite molecular sieve in Example 1 of the present invention;

[0077] Figure 3 The XRD spectrum of Beta / ZSM-5 intergrowth zeolite molecular sieve in Example 2 of the present invention;

[0078] Figure 4 This is the XRD spectrum of the Beta / ZSM-5 co-existing zeolite molecular sieve in Example 3 of the present invention. DETAILED DESCRIPTION

[0079] The present invention is described in detail below in conjunction with specific embodiments and drawings. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the content of the present invention still fall within the scope of protection of the present invention.

[0080] The composition analysis of the catalyst involved in the present invention adopts the existing analysis methods in the art. For example: the composition of the catalyst and molecular sieve is analyzed by X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma emission spectroscopy (ICP); the morphology and composition of the molecular sieve are observed by scanning electron microscopy (SEM); the crystal phase of the molecular sieve in the catalyst is analyzed by X-ray diffraction spectroscopy (XRD), and the relative crystallinity of the Beta molecular sieve and the ZSM-5 molecular sieve in the co-existing molecular sieve is calculated respectively, and then the content of the Beta molecular sieve and the ZSM-5 molecular sieve in the sample is estimated according to the ratio of the relative crystallinity; the metal valence and composition in the catalyst are measured by X-ray photoelectron spectroscopy (XPS). XRF, ICP, XRD and XPS characterization are respectively measured by RigakuZSX100e X-ray fluorescence spectrometer, Varian 700-ES series inductively coupled plasma emission spectrometer, Bruker D8 Advance SS X-ray diffractometer and PerkinElmerPHI5000CESCA X-ray photoelectron spectrometer. The ammonia temperature-programmed desorption (NH3-TPD) characterization of the molecular sieve samples was measured using Tianjin Pengxiang PX200A chemical adsorption instrument, and the medium-strong acid and medium-strong acid content of the molecular sieve samples were quantitatively calculated.

[0081] In the present invention, the hydrocarbon composition of the hydrocracking product is determined by online gas chromatography. The chromatographic model is Agilent7890A, equipped with an FID detector, the gas phase hydrocarbon composition is analyzed by HP-PLOT Q capillary chromatographic column, and the liquid phase hydrocarbon composition is analyzed by HP-INNOWax capillary chromatographic column. The total nitrogen content in the oil product is analyzed by Elab6600SN sulfur and nitrogen element analyzer.

[0082] The calculation basis of the main result data involved in the specific implementation method of the present invention is:

[0083]

[0084] Yield of a hydrocarbon component

[0085] =Content of the component in the liquid phase × yield of the liquid phase + content of the component in the gas phase

[0086] ×Gas phase yield

[0087] In the above formula, C 11+ The contents of the components and a certain hydrocarbon component in the liquid phase are measured by chromatography, and the liquid phase yield is calculated by dividing the weighed mass of the product per hour by the feed amount per hour.

[0088] The raw materials used in the examples are all conventional commercially available raw materials.

[0089] Example 1

[0090] Preparation of Beta / ZSM-5 intergrowth zeolite molecular sieve:

[0091] Silica sol (40wt%, Zhejiang Delixin), aluminum nitrate nonahydrate, sodium hydroxide, and tetraethylammonium hydroxide (35wt%) were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.0125:0.4:12:0.04 according to the oxide ratio. After stirring and aging for 4 hours at 25°C, the obtained mixture was placed in a crystallization kettle and crystallized at 160°C for 4 days. The obtained product was filtered, washed, dried at 120°C, and calcined at 550°C for 6 hours to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. Characterization showed that the molar ratio of silicon aluminum oxide molecules in Beta / ZSM-5 symbiotic zeolite molecular sieve was 75. The XRD spectrum of Beta / ZSM-5 symbiotic zeolite molecular sieve in Example 1 is shown in the figure. Figure 1 As shown, XRD spectrum Figure 2 The characteristic diffraction peaks of Beta molecular sieve appear at 7.6° and 22.4°, and the characteristic diffraction peaks of ZSM-5 molecular sieve appear at 7.9°, 8.9° and 22.5-25°, indicating that Beta / ZSM-5 symbiotic zeolite molecular sieves are prepared in Example 1; the Beta zeolite molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve is calculated to be 60%, and the ZSM-5 zeolite molecular sieve content is 40%; the SEM photo of the Beta / ZSM-5 symbiotic zeolite molecular sieve in Example 1 is shown in Figure 2 As shown, Figure 2Beta zeolite molecular sieve and ZSM-5 zeolite molecular sieve can be observed at the same time. Beta zeolite molecular sieve is small particles with a particle size of 50-500nm, and ZSM-5 zeolite molecular sieve is large particles with a coffin-like morphology and a particle size of 3-6μm.

[0092] Preparation of catalytic diesel hydrocracking catalyst:

[0093] The 30g Beta / ZSM-5 symbiotic zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve. The ratio of the amount of strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve was 3:1 by NH3-TPD characterization and quantitative calculation.

[0094] 20.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 20.7g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. 6.24g of nickel nitrate hexahydrate and 3.02g of ammonium molybdate tetrahydrate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 400°C for 4h in a hydrogen flow rate of 80ml / min to obtain a catalyst composition of: 3.5wt%Ni-5.2wt%MoO2-1.0wt%MoO3 / 50.0wt%intergrowth zeolite molecular sieve-40.3wt%Al2O3.

[0095] Application of catalyst:

[0096] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were shown in Table 1. The reaction results are shown in Table 2.

[0097] Table 1 Raw material properties and hydrocracking reaction conditions

[0098] Example 1 Example 3 Catalytic diesel T95(℃) 340 356 Hydrogen content of catalytic diesel fuel (ppm) 8.8 10.0 Hydrogen partial pressure (Mpa) 7.0 7.0 Inlet temperature(℃) 360 370 Fresh Hydrogen Hydrogen Oil Volume Ratio 540 830 Mixed hydrogen oil volume ratio 2000 2000 <![CDATA[Mass hourly space velocity (h -1 )]]> 1.0 1.0

[0099] Example 2

[0100] Preparation of Beta / ZSM-5 intergrowth zeolite molecular sieve:

[0101] Silica sol (40wt%, Zhejiang Delixin), sodium aluminate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.02:0.1:14:0.25 according to the oxide ratio. After stirring and aging for 6 hours at 25°C, the obtained mixture was placed in a crystallization kettle and crystallized at 160°C for 5 days. The obtained product was filtered, washed, dried at 120°C, and calcined at 550°C for 5 hours to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. Characterization measured that the molar ratio of silicon aluminum oxide molecules of Beta / ZSM-5 symbiotic zeolite molecular sieve is 50. The XRD spectrum of Beta / ZSM-5 symbiotic zeolite molecular sieve in Example 2 is shown as follows Figure 3 As shown, XRD spectrum Figure 2 The characteristic diffraction peaks of Beta molecular sieve appear at 7.6° and 22.4°, and the characteristic diffraction peaks of ZSM-5 molecular sieve appear at 7.9°, 8.9° and 22.5-25°, indicating that Beta / ZSM-5 symbiotic zeolite molecular sieves are prepared in Example 1; the Beta zeolite molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve is calculated to be 50%, and the ZSM-5 zeolite molecular sieve content is 50%.

[0102] Preparation of catalytic diesel hydrocracking catalyst:

[0103] The 30g Beta / ZSM-5 symbiotic zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve. The ratio of the amount of strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve was 1:1 by NH3-TPD characterization and quantitative calculation.

[0104] 20.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 21.1g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. Then 6.24g of nickel nitrate hexahydrate and 2.17g of ammonium metatungstate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 450°C for 4h in a hydrogen flow rate of 80ml / min, and then cooled to 320°C and injected with dimethyl disulfide for 4h to obtain a catalyst composition of: 3.5wt% Ni-3.3wt% WO2-1.7wt% WS2-0.5wt% WO3 / 50wt% intergrowth zeolite molecular sieve-41.0wt% Al2O3.

[0105] Application of catalyst:

[0106] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 1. The reaction results are shown in Table 2.

[0107] Example 3

[0108] Silica gel, sodium aluminate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.005:0.6:18:0.03 according to the oxide ratio. Stir and age at 25°C for 6 hours, then put the obtained mixture into a crystallization kettle and crystallize at 160°C for 5 days. The obtained product was filtered, washed, dried at 120°C, and calcined at 550°C for 5 hours to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. Characterization measured that the molar ratio of silicon aluminum oxide molecules of Beta / ZSM-5 symbiotic zeolite molecular sieve is 170. The XRD spectrum of Beta / ZSM-5 symbiotic zeolite molecular sieve in Example 3 is shown as follows Figure 4 As shown, XRD spectrum Figure 2 The characteristic diffraction peaks of Beta molecular sieve appear at 7.6° and 22.4°, and the characteristic diffraction peaks of ZSM-5 molecular sieve appear at 7.9°, 8.9° and 22.5-25°, indicating that Beta / ZSM-5 symbiotic zeolite molecular sieves are prepared in Example 1; the Beta zeolite molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve is calculated to be 95%, and the ZSM-5 zeolite molecular sieve content is 5%.

[0109] Preparation of catalytic diesel hydrocracking catalyst:

[0110] The 30g Beta / ZSM-5 symbiotic zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve. The ratio of strong acid to strong acid in the hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve was 19:1 by NH3-TPD characterization and quantitative calculation.

[0111] 20.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 20.7g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. 6.24g of cobalt nitrate hexahydrate and 3.02g of ammonium molybdate tetrahydrate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 400°C in a hydrogen atmosphere of 80ml / min for 4h to obtain a catalyst composition of: 3.5wt% Co-5.2wt% MoO2-1.0wt% MoO3 / 50.0wt% intergrowth zeolite molecular sieve-40.3wt% Al2O3.

[0112] Application of catalyst:

[0113] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were shown in Table 1. The reaction results are shown in Table 2.

[0114] Comparative Example 1

[0115] Preparation of catalytic diesel hydrocracking catalyst:

[0116] The preparation process is similar to that of Example 1, except that the molecular sieve in the catalyst is replaced by pure hydrogen-type Beta zeolite molecular sieve.

[0117] The preparation process of pure hydrogen-type Beta zeolite molecular sieve is as follows:

[0118] Silica sol (40wt%, Zhejiang Delixin), aluminum nitrate nonahydrate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.0125:0.55:15:0.06 according to the oxide ratio. After stirring and aging for 4h at 25℃, the obtained mixture was placed in a crystallization kettle and crystallized at 140℃ for 6 days. The obtained product was filtered, washed, dried at 120℃, and calcined at 550℃ for 6h to obtain sodium Beta zeolite molecular sieve. Characterization showed that the molar ratio of silicon and aluminum oxide molecules of sodium Beta zeolite molecular sieve was 75. Take the above 30g sodium-type Beta zeolite molecular sieve, add it to 600g 1mol / L ammonium chloride solution, stir it at 80℃ for 4h, filter, wash, dry it at 120℃ overnight, calcine it at 520℃ for 4h, repeat the above steps once, and obtain hydrogen-type Beta zeolite molecular sieve.

[0119] Application of catalyst:

[0120] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 1. The reaction results are shown in Table 2.

[0121] Example 4

[0122] Preparation of Beta / ZSM-5 intergrowth zeolite molecular sieve:

[0123] Silica sol (40wt%, Zhejiang Delixin), aluminum sulfate 18hydrate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.011:0.1:18:0.3 according to the oxide ratio. After stirring and aging for 6h at 25°C, the obtained mixture was placed in a crystallization kettle and crystallized at 160°C for 5 days. The obtained product was filtered, washed, dried at 120°C, and calcined at 550°C for 5h to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. The Beta zeolite molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve was calculated to be 82% and the ZSM-5 zeolite molecular sieve content was 18%. The characterization results show that the molar ratio of silicon-aluminum oxide molecules in the Beta / ZSM-5 intergrowth zeolite molecular sieve is 90.

[0124] Preparation of catalytic diesel hydrocracking catalyst:

[0125] The 30g Beta / ZSM-5 symbiotic zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve. The ratio of the amount of strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve was 5:1 by NH3-TPD characterization and quantitative calculation.

[0126] 27.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 11.7g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. Then 6.24g of nickel nitrate hexahydrate and 3.02g of ammonium molybdate tetrahydrate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 400°C for 4h in a hydrogen flow rate of 80ml / min to obtain a catalyst composition of: 3.5wt% Ni-5.2wt% MoO2-1.0wt% MoO3 / 67.5wt% intergrowth zeolite molecular sieve-22.8wt% Al2O3.

[0127] Application of catalyst:

[0128] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 1. The reaction results are shown in Table 2.

[0129] Example 5

[0130] Preparation of Beta / ZSM-5 intergrowth zeolite molecular sieve:

[0131] Silica sol (40wt%, Zhejiang Delixin), aluminum sulfate 18hydrate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.004:0.6:16:0.125 according to the oxide ratio. After stirring and aging for 6h at 25℃, the obtained mixture was placed in a crystallization kettle and crystallized at 160℃ for 5 days. The obtained product was filtered, washed, dried at 120℃, and calcined at 550℃ for 5h to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. The Beta molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve was calculated to be 30%, and the ZSM-5 molecular sieve content was 70%. Characterization measured that the molar ratio of silicon aluminum oxide molecules of the Beta / ZSM-5 symbiotic zeolite molecular sieve was 250.

[0132] Preparation of catalytic diesel hydrocracking catalyst:

[0133] The 30g Beta / ZSM-5 symbiotic zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve. The ratio of the amount of strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 symbiotic zeolite molecular sieve was 0.4:1 by NH3-TPD characterization and quantitative calculation.

[0134] 27.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 11.7g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. Then 6.24g of nickel nitrate hexahydrate and 3.02g of ammonium molybdate tetrahydrate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 400°C for 4h in a hydrogen flow rate of 80ml / min to obtain a catalyst composition of: 3.5wt% Ni-5.2wt% MoO2-1.0wt% MoO3 / 67.5wt% intergrowth zeolite molecular sieve-22.8wt% Al2O3.

[0135] Application of catalyst:

[0136] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 1. The reaction results are shown in Table 2.

[0137] Comparative Example 2

[0138] Preparation of Beta / ZSM-5 intergrowth zeolite molecular sieve:

[0139] Silica gel, sodium aluminate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.04:0.6:18:0.16 according to the oxide ratio. After stirring and aging for 6h at 25°C, the obtained mixture was placed in a crystallization kettle and crystallized at 160°C for 5 days. The obtained product was filtered, washed, dried at 120°C, and calcined at 550°C for 5h to obtain Beta / ZSM-5 symbiotic zeolite molecular sieve. The Beta molecular sieve content in the Beta / ZSM-5 symbiotic zeolite molecular sieve was calculated to be 92%, and the ZSM-5 molecular sieve content was 8%. Characterization measured that the molar ratio of silicon aluminum oxide molecules of the Beta / ZSM-5 symbiotic zeolite molecular sieve was 22.

[0140] Preparation of catalytic diesel hydrocracking catalyst:

[0141] The 30g Beta / ZSM-5 intergrowth zeolite molecular sieve obtained above was added to 600g 1mol / L ammonium chloride solution, stirred at 80°C for 4h, filtered, washed, dried at 120°C overnight, calcined at 520°C for 4h, and the above steps were repeated once to obtain a hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve. The ratio of strong acid to strong acid in the hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve was 12:1 by quantitative calculation through NH3-TPD characterization.

[0142] 20.0g of the above hydrogen-type Beta / ZSM-5 intergrowth zeolite molecular sieve and 20.7g of pseudo-boehmite were kneaded and extruded, and then dried at 90°C and calcined at 550°C in air atmosphere for 4 hours to obtain a catalyst carrier. 6.24g of cobalt nitrate hexahydrate and 3.02g of ammonium molybdate tetrahydrate were prepared into a clear solution, and the catalyst carrier was impregnated with an equal volume of metal solution, dried at 100°C, and calcined at 520°C for 2h to obtain a catalyst precursor. The catalyst precursor was reduced at 400°C in a hydrogen atmosphere of 80ml / min for 4h to obtain a catalyst composition of: 3.5wt% Co-5.2wt% MoO2-1.0wt% MoO3 / 50.0wt% intergrowth zeolite molecular sieve-40.3wt% Al2O3.

[0143] Application of catalyst:

[0144] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 3. The reaction results are shown in Table 2.

[0145] Comparative Example 3

[0146] Preparation of catalytic diesel hydrocracking catalyst:

[0147] The preparation process is similar to that of Example 1, except that the intergrown zeolite molecular sieve in the catalyst is replaced by a mechanical mixture of 60% pure hydrogen-type Beta zeolite molecular sieve and 40% pure hydrogen-type ZSM-5 zeolite molecular sieve.

[0148] The preparation method of pure hydrogen-type Beta zeolite molecular sieve is as follows:

[0149] Silica sol (40wt%, Zhejiang Delixin), aluminum nitrate nonahydrate, sodium hydroxide, tetraethylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TEAOH:H2O:Na2O=1:0.0125:0.55:15:0.06 according to the oxide ratio. After stirring and aging for 4h at 25℃, the obtained mixture was placed in a crystallization kettle and crystallized at 140℃ for 6 days. The obtained product was filtered, washed, dried at 120℃, and calcined at 550℃ for 6h to obtain sodium Beta zeolite molecular sieve. Characterization showed that the molar ratio of silicon and aluminum oxide molecules of sodium Beta zeolite molecular sieve was 75. Take the above 30g sodium Beta zeolite molecular sieve, add it to 600g 1mol / L ammonium chloride solution, stir it at 80℃ for 4h, filter, wash, dry it at 120℃ overnight, calcine it at 520℃ for 4h, repeat the above steps once, and obtain hydrogen Beta zeolite molecular sieve.

[0150] The preparation method of pure hydrogen-type ZSM-5 zeolite molecular sieve is as follows:

[0151] Silica sol (40wt%, Zhejiang Delixin), aluminum nitrate nonahydrate, sodium hydroxide, tetrapropylammonium hydroxide (35wt%), and deionized water were mixed evenly. The molar ratio of silicon source, aluminum source, template, water and alkali in the obtained mixture was SiO2:Al2O3:TPAOH:H2O:Na2O=1:0.0125:0.2:25:0.06 according to the oxide ratio. After stirring and aging for 4h at 25℃, the obtained mixture was placed in a crystallization kettle and crystallized at 170℃ for 2 days. The obtained product was filtered, washed, dried at 120℃, and calcined at 550℃ for 6h to obtain a sodium-type ZSM-5 zeolite molecular sieve. Characterization showed that the molar ratio of silicon-aluminum oxide molecules of the sodium-type ZSM-5 zeolite molecular sieve was 75. Take the above 30g sodium ZSM-5 zeolite molecular sieve, add it to 600g 1mol / L ammonium chloride solution, stir it at 80℃ for 4h, filter, wash, dry it at 120℃ overnight, calcine it at 520℃ for 4h, repeat the above steps once, and obtain hydrogen ZSM-5 zeolite molecular sieve.

[0152] Application of catalyst:

[0153] The hydrocracking reactor was loaded with 10.0 g of catalyst, and the properties of the hydrocatalytic diesel feedstock used and the hydrocracking reaction conditions were the same as those in Example 1. The reaction results are shown in Table 2.

[0154] Table 2 Comparison of hydrocracking reaction results between the embodiment and the comparative example

[0155]

[0156] It can be seen from Example 1, Comparative Examples 1 and 3 and Table 2 that, compared with adding only Beta zeolite molecular sieve or adding Beta zeolite molecular sieve and ZSM-5 intergrowth zeolite molecular sieve at the same time, the hydrocracking catalyst of the present invention has significantly better light aromatics and benzene yields due to the addition of specific Beta / ZSM-5 intergrowth zeolite molecular sieves.

[0157] It can be seen from Comparative Example 2 and Table 2 that when the molar ratio of the Beta / ZSM-5 intergrowth zeolite molecular sieve silicon aluminum oxide molecules is below 25, the yield of light aromatics and benzene cannot be effectively improved.

[0158] It can be seen from Examples 1-5 and Table 2 that the Beta / ZSM-5 co-existing zeolite molecular sieve and catalytic diesel hydrocracking catalyst of the present invention are applied to the hydrocracking reaction of hydrogenated catalytic diesel, which can effectively improve the problem of low light aromatics selectivity of conventional Beta zeolite molecular sieve-based catalytic diesel hydrocracking catalysts and obtain high light aromatics and benzene yields.

Claims

1. A Beta / ZSM-5 intergrowth zeolite molecular sieve having the topological structures of BEA and MFI, wherein: The particle size of the BEA topological structure is 50-500 nm, and the particle size of the MFI topological structure is 3-6 μm; preferably, the molar ratio of the Beta / ZSM-5 intergrowth zeolite molecular sieve silicon aluminum oxide molecules is 25-300, preferably 50-200.

2. The Beta / ZSM-5 intergrowth zeolite molecular sieve according to claim 1, characterized in that: The X-ray diffraction spectrum of the Beta / ZSM-5 intergrown zeolite molecular sieve simultaneously exhibits characteristic diffraction peaks of the Beta zeolite molecular sieve and characteristic diffraction peaks of the ZSM-5 zeolite molecular sieve; preferably, the X-ray diffraction spectrum of the Beta / ZSM-5 intergrown zeolite molecular sieve exhibits characteristic diffraction peaks of the Beta molecular sieve at 7.6° and 22.4°, and / or, characteristic diffraction peaks of the ZSM-5 molecular sieve at 7.9°, 8.9° and 22.5-25°; and / or, The content of ZSM-5 zeolite molecular sieve in the Beta / ZSM-5 intergrowth zeolite molecular sieve is 5-80%, preferably 20-50%, and the content of Beta zeolite molecular sieve is 20-95%, preferably 50-80%.

3. The Beta / ZSM-5 intergrowth zeolite molecular sieve according to any one of claims 1 to 2, characterized in that: The Beta / ZSM-5 intergrown zeolite molecular sieve is obtained by a one-step hydrothermal synthesis. Preferably, the Beta / ZSM-5 intergrown zeolite molecular sieve is obtained by a preparation method comprising aging a mixture containing a silicon source, an aluminum source, a template and a base, followed by a crystallization step.

4. A method for preparing the Beta / ZSM-5 symbiotic zeolite molecular sieve as described in any one of claims 1 to 3, wherein the Beta / ZSM-5 symbiotic zeolite molecular sieve is obtained by one-step hydrothermal synthesis. Preferably, the method for preparing the Beta / ZSM-5 symbiotic zeolite molecular sieve comprises the steps of aging a mixture comprising a silicon source, an aluminum source, a template and a base, and then crystallizing it.

5. The preparation method according to claim 4, characterized in that: The silicon source is selected from at least one of silica sol, silica gel, water glass, white carbon black, and tetraethyl orthosilicate; and / or, The aluminum source is selected from at least one of sodium aluminate, pseudo-boehmite, aluminum nitrate, aluminum sulfate, and aluminum sol; and / or, The template agent is selected from tetraethylammonium hydroxide; and / or, The base is selected from sodium hydroxide.

6. The preparation method according to claim 4, characterized in that: The molar ratio of the silicon source, aluminum source, template, water and alkali in the mixture is SiO2:Al2O3:TEAOH:H2O:Na2O=1:(0.0033-0.04):(0.1-0.6):(5-30):(0.01-0.5) based on the oxide ratio, preferably SiO2:Al2O3:TEAOH:H2O:Na2O=1:(0.005-0.02):(0.25-0.55):(5-20):(0.02-0.3).

7. The preparation method according to claim 4, characterized in that: The aging temperature is 20-35°C; and / or, the aging time is more than 2 hours, preferably 4-8 hours; and / or, The crystallization temperature is 150-180° C.; and / or the crystallization time is 3-7 days, preferably 4-5 days.

8. The preparation method according to claim 4, characterized in that: The preparation method of the Beta / ZSM-5 intergrowth zeolite molecular sieve further comprises the steps of solid-liquid separation of the crystallized mixture, and washing, drying and calcining the solid product; preferably, The drying temperature is 100-120° C.; and / or the roasting temperature is 500-600° C.; and / or the roasting time is 4-6 hours.

9. A catalytic diesel hydrocracking catalyst comprising the following components: a) Beta / ZSM-5 intergrowth zeolite molecular sieve; b) metal active component; c) binder; Preferably, the above-mentioned Beta / ZSM-5 intergrown zeolite molecular sieve is selected from at least one of the Beta / ZSM-5 intergrown zeolite molecular sieve according to any one of claims 1-3 and the Beta / ZSM-5 intergrown zeolite molecular sieve prepared according to any one of claims 4-8; more preferably, the Beta / ZSM-5 intergrown zeolite molecular sieve is a hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve; further preferably, based on the NH3-TPD result, the ratio of the amount of medium and strong acid to the amount of strong acid in the hydrogen-type Beta / ZSM-5 intergrown zeolite molecular sieve is (0.2-20):1, preferably (1-5):

1.

10. The catalytic diesel hydrocracking catalyst according to claim 9, characterized in that: The metal active component includes at least one of Group VIII metals and Group VIII metal sulfides and at least one of Group VIB metal oxides and Group VIB metal sulfides, and preferably includes at least one of Group VIII metal-Group VIB metal oxide, Group VIII metal sulfide-Group VIB metal sulfide, and Group VIII metal sulfide-Group VIB metal oxide-Group VIB metal sulfide.

11. The catalytic diesel hydrocracking catalyst according to claim 10, characterized in that: The Group VIII metal includes at least one of platinum, palladium, ruthenium, cobalt, nickel and iridium; and / or, The VIB group metal oxide includes at least one of molybdenum and tungsten oxides; preferably at least one of molybdenum dioxide, molybdenum trioxide, tungsten dioxide, and tungsten trioxide; and / or, The Group VIII metal sulfide comprises at least one of sulfides of iron, cobalt and nickel; and / or, The VIB group metal sulfide includes at least one of molybdenum disulfide and tungsten disulfide.

12. The catalytic diesel hydrocracking catalyst according to claim 9, characterized in that: The binder includes at least one of aluminum oxide, silicon oxide, silicon oxide-aluminum oxide composite, and amorphous silicon aluminum.

13. The catalytic diesel hydrocracking catalyst according to any one of claims 9 to 12, characterized in that: In terms of mass percentage, The mass of the Beta / ZSM-5 intergrown zeolite molecular sieve accounts for 5-80wt% of the mass of the catalyst, preferably 20-75wt%, more preferably 30-70wt%; and / or, The metal active component accounts for 3-35 wt% of the catalyst mass, preferably 5-23 wt%.

14. The catalytic diesel hydrocracking catalyst according to claim 10, characterized in that: In terms of mass percentage, The Group VIII metal and / or Group VIII metal sulfide accounts for 0.01-10 wt %, preferably 0.5-8 wt % of the catalyst mass; and / or, The VIB Group metal oxide and / or sulfide accounts for 3-25 wt %, preferably 5-15 wt % of the catalyst mass.

15. A method for preparing a catalytic diesel hydrocracking catalyst as claimed in any one of claims 9 to 14, comprising loading the metal active component on a carrier comprising Beta / ZSM-5 intergrown zeolite molecular sieve and a binder, and then reducing and / or sulfurizing to obtain the catalytic diesel hydrocracking catalyst.

16. Use of the catalytic diesel hydrocracking catalyst according to any one of claims 9 to 14 or the catalytic diesel hydrocracking catalyst obtained by the preparation method according to claim 15 in a hydrogenation catalytic diesel hydrocracking reaction.

17. The use according to claim 16, characterized in that: The application comprises the step of contacting the catalytic diesel hydrocracking catalyst with hydrogenated catalytic diesel under hydrocracking conditions; preferably, the catalytic diesel T95 is ≤360°C, preferably ≤345°C, and the total nitrogen content of the hydrogenated catalytic diesel obtained after hydrofining is ≤15ppm, preferably ≤10ppm.

18. The use according to claim 17, characterized in that: The process conditions of the hydrocracking reaction include: Reactor inlet temperature 280-450°C, preferably 310-430°C, more preferably 350-410°C; and / or, Hydrogen partial pressure 5-10 MPa, preferably 5-9 MPa, more preferably 6-8 MPa; and / or, Mass airspeed 0.5-2.0h -1 , preferably 0.6-1.5h -1 , more preferably 0.8-1.2h -1 and / or, The volume ratio of fresh hydrogen to hydrogenated catalytic diesel is 400-1000, preferably 500-800, more preferably 500-600; and / or, The volume ratio of hydrogen to oil of the mixed hydrogen and hydrogenated catalytic diesel is 1000-5000, preferably 2000-4000, more preferably 2000-3000.

19. The use according to any one of claims 16 to 18, characterized in that: The hydrocracking reaction product satisfies: C 11+ The component single-pass conversion rate is greater than 85%, preferably greater than 90%; and / or, C 6-10 The aromatics yield is ≥35wt%, preferably ≥38wt%, more preferably ≥40wt%; and / or the benzene yield is ≥2.6wt%, preferably ≥3.0wt%, more preferably ≥3.2wt%.

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