Process for the preparation of a bulk hydrocracking catalyst

Abstract

The application discloses a preparation method of a bulk-phase hydrocracking catalyst, which comprises the following steps: (1) adding a solution containing W, Ni and Al into a gelatinization reaction tank, and dropping a basic precipitator to perform a gelatinization reaction; in the gelatinization reaction process, the pH value is controlled by the basic precipitator to gradually increase from an initial value to a final value, and a molybdenum-containing solution is added after each increase; (2) continuously performing n times of aging on the slurry obtained in the step (1), adding 1 / n sodium metaaluminate solution and 1 / n beta molecular sieve slurry in each aging process, uniformly mixing, filtering, and obtaining solid-phase materials; and (3) preparing a hydrocracking catalyst from the solid-phase materials. The catalyst prepared by the method has the advantages of uniform dispersion of active metals, large surface-phase active site density, small and uniformly-distributed oxide particle size, good synergistic effect of active components and acidic components, good nitrogen resistance, and the like, and is suitable for application in a hydrocracking process of No. 5 industrial-grade white oil and lubricating oil base oil.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of petroleum refining, and particularly relates to a preparation method of a bulk-phase hydrocracking catalyst. BACKGROUND

[0002] The hydrocracking diesel fraction has the characteristics of water-white color, low impurity content, and high saturated hydrocarbon content, and can be used to produce various white oils, rust-proof oils, transformer oils, aluminum cold rolling oils, etc. The hydrocracking tail oil fraction is suitable for use as a lubricating oil base oil. The industrial white oil has a pour point index of -3 to -9℃ and an aromatic hydrocarbon mass content of not more than 5% according to different grades. The transformer oil has a pour point index of -10 to -50℃ and a polycyclic aromatic hydrocarbon content of less than 3% according to different minimum cold operating temperatures in actual applications. According to the product indexes of special oils, the hydrocracking catalyst needs to have high isomerization performance and high aromatic hydrocarbon conversion capacity. The existing hydrocracking catalyst system is difficult to meet both requirements. At present, the acid component commonly used in hydrocracking is Y molecular sieve, β molecular sieve, and ZSM-5 molecular sieve, and the β molecular sieve has the best isomerization performance and can meet the pour point index requirement of the industrial white oil, but it is difficult for the conventional supported hydrocracking catalyst and the bulk-phase catalyst prepared by the existing technology to meet the polycyclic aromatic hydrocarbon content requirement of the industrial white oil.

[0003] Hydrocracking is a conversion process in which hydrocarbon molecules and hydrogen are cracked and hydrogenated on the surface of a catalyst to generate lighter molecules under high pressure, and hydrogenation desulfurization, denitrification, and hydrogenation of unsaturated hydrocarbons also occur. The traditional supported hydrocracking catalyst is limited by the pore structure of the carrier, and the active metal loading is generally not more than 30wt%, and the hydrogenation activity of the catalyst is far from the aromatic hydrocarbon conversion activity required for producing high-value-added special oil products. The bulk-phase hydrocracking catalyst prepared by the coprecipitation method has a high active metal content, but the oxide particles generated during the coprecipitation reaction have different sizes, the pore volume and specific surface area of the catalyst are small, the utilization rate of the active metal is low, the molecular sieve is added after the active metal is precipitated, and the pores of the oxide particles and the pores of the molecular sieve are not interconnected, which reduces the mutual cooperation of the acid component and the hydrogenation component and the diffusion performance of the catalyst, thereby weakening the hydrogenation cracking activity of the bulk-phase catalyst. Therefore, the bulk-phase catalyst prepared by the existing technology still cannot meet the hydrogenation activity requirement for producing high-value-added special oil products. At the same time, the nitrogen compounds in the hydrocracking raw material have different degrees of poisoning (shielding) effect on the acid sites of the hydrocracking catalyst, which requires improving the nitrogen tolerance of the hydrocracking catalyst. The hydrocracking catalyst with good nitrogen tolerance can improve the adaptability of the catalyst to raw materials and prolong the operation cycle of the industrial device.

[0004] Bulk catalyst is the most active hydrogenation catalyst at present. Bulk hydrogenation catalyst can get rid of the limitation of metal content, and can arbitrarily adjust the proportion of each active component in the catalyst to improve the hydrogenation performance of the catalyst. The combination of active metal components in the hydrogenation catalyst is better than the single component activity. The combination of W-Ni in the metal component has the best hydrogenation saturation activity, and the combination of Mo-Ni has the best hydrogenation denitrification. The size and distribution of metal oxide particles in the bulk catalyst have a great influence on the distribution of hydrogenation active metals and the interaction between different hydrogenation active metals, which further affects the hydrogenation activity of the bulk catalyst. At the same time, the pore size and specific surface area of the catalyst also affect the hydrogenation activity of the bulk catalyst.

[0005] CN106179462A discloses a kind of hydrocracking catalyst and its preparation method, the method first uses positive method to prepare the precipitate slurry I containing Ni, Al component, then uses parallel flow method to prepare the precipitate slurry II containing W, Si, Al component, two kinds of precipitate slurry are mixed evenly, after aging, filtration, the obtained material is mixed into urea, water vapor is carried out hydrothermal treatment, then Y type molecular sieve suspension is added. The catalyst oxide obtained by the method is of different sizes, and the surface active metal appears excessive accumulation after hydrothermal treatment, which does not improve the utilization rate of surface active metal. At the same time, after adding molecular sieve, the mutual cooperation of acid component and hydrogenation component of the catalyst is greatly reduced.

[0006] CN103055923A discloses a kind of preparation method of hydrocracking catalyst. The method is as follows: preparing an acidic mixed solution A containing hydrogenation active metal and silicon, preparing an alkaline sodium aluminate solution B, then adding the acidic mixed solution A, the alkaline solution B and the gas CO2 into the reaction tank containing clean water in parallel flow to form a gel, adding a Y type molecular sieve suspension to mix evenly, filtering, drying, shaping, and then washing, drying and calcining to obtain a hydrocracking catalyst. This method can increase the pore volume and specific surface area of the catalyst, but the method only relies on the carbonates generated in the precipitation to release gas during calcination to increase the pore volume, specific surface area and improve the dispersion of active catalyst metal, which is limited. At the same time, it is easy to cause the aggregation of active metal in the catalyst.

[0007] CN110038617A discloses a kind of hydrocracking catalyst and its preparation method. The hydrocracking catalyst is a bulk catalyst. The catalyst is first prepared by mixing solution A containing Ni, W and Al components with a precipitating agent in parallel flow to form a gel, then the obtained slurry is aged, and then solution B containing W, Si and Al components is added to the aged slurry in parallel flow to react, and then a molecular sieve suspension is added to age, and then the hydrocracking catalyst is prepared by post-treatment. The specific surface area and pore volume of the catalyst are small, and the hydrogenation activity cannot meet the standard of industrial grade white oil product.

[0008] The hydrogenation activity of the catalyst prepared by the prior art cannot meet the production of industrial white oil, therefore, improving the hydrogenation activity of the bulk catalyst and improving the mutual cooperation between the hydrogenation component and the acidic component are the keys for the bulk hydrogenation cracking catalyst to meet the production of industrial white oil. SUMMARY

[0009] In view of the deficiencies of the prior art, the application provides a preparation method of a bulk hydrogenation cracking catalyst.

[0010] The preparation method of the bulk hydrogenation cracking catalyst comprises the following steps:

[0011] (1) adding a W, Ni and Al-containing solution into a gelation reaction tank, and adding a precipitant A and a precipitant B into the reaction tank in parallel to perform a gelation reaction; in the gelation reaction process, the pH value is controlled to be gradually increased from an initial value to a final value, and a molybdenum-containing solution is added after each increase; the number of increases is 2-10, and preferably 2-8;

[0012] (2) continuously performing n times of aging on the slurry obtained in step (1), adding 1 / n sodium metaaluminate solution and 1 / n beta molecular sieve slurry in each aging process, uniformly mixing, filtering the slurry obtained after the aging, and obtaining a solid-phase material; wherein the aging adopts a pH value gradually decreasing aging process;

[0013] (3) drying, shaping and washing the solid-phase material obtained in step (2), and then drying and calcining to obtain a hydrogenation cracking catalyst.

[0014] In the method, the W-containing, Ni-containing and Al-containing solution in step (1) has a WO3 weight concentration of 5-140 g / L, preferably 15-130 g / L, a NiO weight concentration of 5-130 g / L, preferably 10-125 g / L, and an Al2O3 weight concentration of 2-90 g / L, preferably 6-85 g / L; wherein, when the W-containing, Ni-containing and Al-containing solution is prepared, the commonly used tungsten source is ammonium metatungstate, the aluminum source is one or more of aluminum nitrate, aluminum sulfate, aluminum chloride and aluminum acetate, and the commonly used nickel source is one or more of nickel sulfate, nickel nitrate and nickel chloride.

[0015] In the method, the precipitant A in step (1) is a mixed solution of sodium hydroxide and sodium bicarbonate, the precipitant B is ammonia water, the concentration of the mixed solution of sodium hydroxide and sodium bicarbonate is 7wt%-20wt%, the molar ratio of sodium hydroxide to sodium bicarbonate is 0.2:1-0.8:1, preferably 0.3:1-0.7:1, the concentration of ammonia water is 4wt%-8wt%, and the molar ratio of ammonia water to the mixed solution of sodium hydroxide and sodium bicarbonate is 0.1:1-0.45:1, preferably 0.15:1-0.40:1.

[0016] In the method, at the beginning of the gelation reaction in step (1), the pH is controlled to an initial value of 5.0-6.5 by using a precipitant, the final pH value is 8.0-10.5, the gelation reaction temperature is 40-90℃, and the gelation reaction time is 0.3-6.0 hours.

[0017] In the method, in the gelation reaction in step (1), after each increment, the pH value is preferably constant for 0.05-0.5 hours, and the pH increment can be the same or different each time, and the pH increment is preferably not greater than the pH increment of the previous time.

[0018] In the method, in the Mo-containing solution in step (1), the weight concentration of Mo (calculated as MoO3) is 10-150g / L, preferably 10-140g / L; when preparing the Mo-containing solution, the molybdenum source is generally ammonium molybdate. The Mo-containing solution is added in several portions according to the number of pH increments, and the volume of the Mo-containing solution added each time can be the same or different, and the total amount of the Mo-containing solution is determined according to the composition of the catalyst.

[0019] In the method, the weight concentration of Al (calculated as Al2O3) in the sodium aluminate solution in step (2) is 5-75g / L, preferably 8-65g / L. The sodium aluminate solution is divided into n portions (n is 2-8) by volume according to the number of additions, and is preferably divided equally by volume. The beta molecular sieve slurry is divided into n portions (n is 2-8) by volume according to the number of additions, and is preferably divided equally by volume.

[0020] In the method, the aging temperature in step (2) is 60-98℃, preferably 65-92℃.

[0021] In the method, the pH value in step (2) is gradually decreased in the aging process: the reaction slurry is dropped into 1 / n sodium metaaluminate solution for pH value adjustment, the pH value is controlled at 11.5-13.5, 1 / n beta molecular sieve slurry is added, and the aging time is 0.05-0.5 hours; then the pH value is adjusted to 8.5-10.5, and the aging time is 0.05-0.5 hours; finally, the pH value is adjusted to 4.0-6.5, and the aging time is 0.05-0.5 hours, wherein n is an integer of 2-8. Similarly (i.e., the pH value is controlled to 11.0-13.5 again, and the aging time is 0.05-0.5 hours).

[0022] In the aging process, in addition to using sodium metaaluminate solution for pH value adjustment in the first stage, the acids and bases used for pH value adjustment in the other stages can be inorganic salts, inorganic acids and inorganic bases containing no aluminum element, the inorganic acids can be hydrochloric acid and acetic acid, the inorganic bases can be one or more of sodium carbonate, sodium bicarbonate, ammonia water and sodium hydroxide, and the concentration and amount of the acid and base solution can be adjusted according to the actual preparation needs.

[0023] In the method, in step (2), the Al added in the sodium metaaluminate solution accounts for 5%-50% of the total Al in the obtained hydrocracking catalyst, preferably 6%-45%, calculated as Al2O3.

[0024] In the method, the beta molecular sieve in step (2) has the following properties: the molar ratio of silicon oxide to aluminum oxide is 30-90; the specific surface area is 430-780 m 2 / g, preferably 400-700 m 2 / g; the pore volume is 0.30-0.90 cm 3 / g, preferably 0.35-0.85 cm 3 / g; the infrared acid acid amount is 0.10-0.45 mmol / g, preferably 0.18-0.40 mmol / g. The beta molecular sieve slurry is a mixture of the beta molecular sieve and deionized water stirred uniformly, and the solid-liquid mass ratio is 1:1.2-1:5.5.

[0025] In the method of the present application, the drying, shaping and washing in step (3) can be carried out by using conventional methods in the art. The drying conditions are as follows: drying at 40-150°C for 1-48 hours, preferably at 50-120°C for 4-36 hours. During the shaping process, conventional shaping aids such as one or more of a peptizing agent, an extrusion aid and the like can be added as needed. The peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, oxalic acid and the like, and the extrusion aid is one or more of substances that are beneficial to extrusion shaping, such as sesbania gum, carbon black, graphite powder, citric acid and the like, and the amount of the extrusion aid is 1-10 wt% of the total material on a dry basis. The washing is generally carried out using deionized water or a solution containing decomposable salts (such as ammonium acetate, ammonium chloride, ammonium nitrate and the like) and washing to neutral. In the method of preparing the hydrocracking catalyst of the present application, the shape of the catalyst can be a sheet, a sphere, a cylindrical strip or a special-shaped strip (three-leaf clover, four-leaf clover) as needed, and preferably a cylindrical strip or a special-shaped strip (three-leaf clover, four-leaf clover). The diameter of the catalyst can be a fine strip of 0.8-2.0 mm or a thick strip of >2.5 mm.

[0026] In the method of the present application, the calcination conditions in step (3) are as follows: calcination at 350-650°C for 1-24 hours, preferably at 400-600°C for 2-12 hours.

[0027] The present application also provides a hydrocracking catalyst which is a bulk hydrocracking catalyst, and the hydrocracking catalyst comprises a hydrogenation active metal component, amorphous alumina and a β molecular sieve. The pore size distribution of the hydrocracking catalyst is as follows: the pore volume of pores with a diameter of 6 nm or less accounts for 2-14% of the total pore volume, the pore volume of pores with a diameter of 6-10 nm accounts for 55-75% of the total pore volume, the pore volume of pores with a diameter of 10-15 nm accounts for 9-25% of the total pore volume, and the pore volume of pores with a diameter of 15 nm or more accounts for 8-23% of the total pore volume. The specific surface area of the catalyst is 200-600 m 2 / g, and the pore volume is 0.28-1.2 mL / g. The molar ratio of W / Mo is 1:13-10:1, preferably 1:11-9:1, and the molar ratio of Ni / (Mo+W) is 1:14-13:1, preferably 1:12-12:1. The ratio of the sum of the weight contents of the surface phase active metal components WO3 and NiO to the sum of the weight contents of the bulk phase active metal components WO3 and NiO is 2.4:1-6.5:1, preferably 3.5:1-6.2:1, and the ratio of the sum of the weight contents of the surface phase active metal components MoO3 and NiO to the sum of the weight contents of the bulk phase active metal components MoO3 and NiO is 2.3:1-5.6:1, preferably 2.5:1-5.3:1.

[0028] The average particle size of the tungsten, molybdenum and nickel active metal oxide particles in the catalyst is 8-12 nm. Preferably, the particle size distribution of the oxide particles is as follows: the number of particles with a particle size less than 8 nm is 3-15% of the total number of particles, the number of particles with a particle size of 8-12 nm is 70-90% of the total number of particles, and the number of particles with a particle size greater than 12 nm is 6-18% of the total number of particles.

[0029] In the method for preparing the hydrocracking catalyst, the shape of the catalyst can be sheet, spherical, cylindrical strip or irregular strip (three-leaf clover, four-leaf clover) according to requirements, and preferably cylindrical strip or irregular strip (three-leaf clover, four-leaf clover). The diameter of the catalyst can be 0.8-2.0 mm for thin strips or >2.5 mm for thick strips.

[0030] The hydrocracking catalyst of the present application can be used in a hydrocracking process for producing special oil and base oil of lubricating oil, and is particularly suitable for a hydrocracking process for base oil feedstock of No. 5 industrial grade white oil and high viscosity index lubricating oil.

[0031] The heavy feedstock suitable for the hydrocracking catalyst of the present application has a wide range, which includes one or more of vacuum gas oil, coking gas oil, deasphalted oil, thermal cracking gas oil, catalytic cracking gas oil, catalytic cracking cycle oil and various hydrocarbon oils, and generally contains hydrocarbons with a boiling point of 250-550℃ and nitrogen content of 300-2500 μg / g. After a pretreatment process by hydrocracking, the nitrogen content in the feedstock of the hydrocracking catalyst of the present application is less than 150 μg / g, i.e. the nitrogen content in the feedstock of the reaction section of the hydrocracking catalyst is less than 150 μg / g, and further more than 10 μg / g, or even more than 50 μg / g. The hydrocracking catalyst of the present application still has high activity, stability and good product quality under the condition of high nitrogen content feedstock (less than 150 μg / g).

[0032] Compared with the prior art, the present application has the following advantages:

[0033] 1. The method of the present application controls the preparation steps and conditions comprehensively, so that the oxide particles have small size and uniform distribution, can fully contact with the molecular sieve, the pore volume and pore size of the catalyst are increased, the pore size distribution is concentrated in 6-10 nm, the probability of mutual penetration of the pore channels of the active component carrier and the molecular sieve is increased, the diffusion performance of the catalyst and the mutual cooperation of the hydrogenation component and the acid component are improved, the hydrogenation activity of the catalyst is enhanced, the organic nitrogen-containing compounds which have great toxic effect on the acid centers of the catalyst can be hydrogenated more and faster, the protection of the acid centers of the catalyst is achieved, the nitrogen tolerance of the hydrocracking catalyst is improved, and the properties of the hydrocracking product are improved.

[0034] 2、The present application adopts the mixed solution of sodium hydroxide and sodium carbonate and ammonia water as a precipitant in the reaction process, and by controlling the mass ratio between sodium hydroxide and sodium carbonate and the weight concentration of ammonia water, the problems of small pore volume and specific surface area of the bulk catalyst, poor cohesiveness of the gel material, large oxide particles and the like are effectively overcome compared with single precipitants such as ammonia water, sodium hydroxide and sodium carbonate, and the generated particles are uniform in size, which is more conducive to the interaction between the acid center and the hydrogenation center.

[0035] 3、The present application precipitates the solution containing W, Ni and Al at a specific pH value by using the pH value stepwise increasing gelation method, prevents the generation of large particle oxides in the gelation process, uniformly disperses the active metals, and the addition of Mo in the pH value stepwise increasing process is more conducive to the interaction between the active metals, thereby greatly improving the hydrogenation activity of the catalyst.

[0036] 4、The present application swings the pH value during aging and adds sodium metaaluminate solution in several times, dissolves the amorphous oxide in the oxide particles by swinging the pH value, modifies the size of the oxide particles by adding the sodium metaaluminate solution, and makes the metal oxide particles better contact with the molecular sieve by synchronously adding the molecular sieve each time, thereby promoting the synergistic effect. DETAILED DESCRIPTION

[0037] In the present application, the specific surface area and pore volume are determined by low-temperature liquid nitrogen adsorption method, and the mechanical strength is determined by side pressure method.

[0038] In the present application, the content of the surface active metal of the catalyst is determined by X-ray photoelectron spectroscopy (XPS), and the content of the bulk active metal of the catalyst is determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES).

[0039] In the present application, wt% is mass fraction, and v% is volume fraction.

[0040] In the present application, the average particle size (D50 particle size) and particle size distribution of the active metal oxide microparticles are measured by a nanoparticle size and Zeta potential analyzer (Zetasizer Nano ZS).

[0041] In the present application, the properties of the beta molecular sieve used are shown in Table 7, and the properties of the Y molecular sieve are shown in Table 8.

[0042] Example 1

[0043] Ammonium metatungstate, nickel chloride and aluminum chloride were added to dissolving tank 1 containing deionized water to prepare a W, Ni, Al-containing solution, in which the concentration of W (as WO3) was 58 g / L, the concentration of Ni (as NiO) was 44 g / L, and the concentration of Al (as Al2O3) was 28 g / L. Ammonium molybdate was added to dissolving tank 2 containing deionized water to prepare a Mo-containing solution, in which the concentration of Mo (as MoO3) was 32 g / L, and the solution was divided into 5 equal parts by volume. The Al content of the sodium aluminate solution was 30% of the total Al (as Al2O3) in the obtained hydrocracking catalyst, and the solution was divided into 5 equal parts by volume. A β-molecular sieve slurry was prepared at a solid-to-liquid ratio of 1:3, and the slurry was divided into 5 equal parts by volume. The W, Ni, Al-containing solution was placed in a reaction tank, and a co-current flow of a mixed solution of sodium hydroxide and sodium bicarbonate with a concentration of 12 wt% and ammonia water with a concentration of 6% was added to the reaction tank to perform a gelation reaction at a reaction temperature of 60°C. The molar ratio of sodium hydroxide to sodium bicarbonate was 0.4:1, and the molar ratio of ammonia water to the sum of the moles of sodium hydroxide and sodium bicarbonate was 0.25. The initial pH value was controlled to be 5.1, and the final pH value at the end of the reaction was adjusted to be 9.1 by increasing the pH value 5 times, with each increase being 0.8. After each increase, one part of the Mo-containing solution was added, and the pH value of the adjusted reaction slurry was kept constant for 12 minutes to form a precipitate slurry containing nickel, molybdenum, tungsten and aluminum. The obtained slurry was aged at an aging temperature of 76°C. During the aging, one part of the sodium aluminate solution was first added to control the pH value to be 13.3, one part of the β-molecular sieve slurry was added, the aging time was 0.15 hours, then the aging pH value was controlled to be 9.4, the aging time was 0.2 hours, then the pH value was controlled to be 5.5, the aging time was 0.15 hours, and the above process was repeated 5 times to complete the aging. The aged slurry was filtered, the filter cake was dried at 100°C for 8 hours, was rolled and was extruded into a strip. The extruded material was washed with deionized water at room temperature until neutral. The dried material was calcined at 530°C for 5 hours to obtain catalyst A. The composition and main properties of the catalyst are shown in Table 1.

[0044] Example 2

[0045] Ammonium metatungstate, nickel chloride and aluminum chloride were added to dissolving tank 1 containing deionized water to prepare a W, Ni, Al-containing solution, the W-containing solution having a W concentration of 44 g / L as WO3, the Ni-containing solution having a Ni concentration of 52 g / L as NiO, and the Al-containing solution having an Al concentration of 29.9 g / L as Al2O3. Ammonium molybdate was added to dissolving tank 2 containing deionized water to prepare a Mo-containing solution, the Mo-containing solution having a Mo concentration of 36 g / L as MoO3, and the Mo-containing solution was divided into 6 equal parts by volume. The Al content of the sodium aluminate solution was 35% of the total Al (as Al2O3) in the resulting hydrocracking catalyst, and the sodium aluminate solution was divided into 5 equal parts by volume. A β-molecular sieve slurry was prepared at a solid-to-liquid ratio of 1:3.8, and the β-molecular sieve slurry was divided into 5 equal parts by volume. The W, Ni, Al-containing solution was placed in a reaction tank, and the reaction temperature was 55°C. A mixed solution of sodium hydroxide and sodium bicarbonate having a concentration of 13 wt% and ammonia water having a concentration of 7 wt% were added to the reaction tank in a concurrent manner to perform a gelation reaction. The molar ratio of sodium hydroxide to sodium bicarbonate was 0.5:1, the molar ratio of ammonia water to the sum of the moles of sodium hydroxide and sodium bicarbonate was 0.29, the initial pH value was controlled to be 5.6, the final pH value at the end of the reaction was adjusted to be 9.8 by increasing the pH value 6 times, the pH value was increased by 0.7 each time, and after the pH value was adjusted each time, one part of the Mo-containing solution was added. The pH value of the adjusted reaction slurry was kept constant for 14 minutes, a precipitate slurry containing nickel, molybdenum, tungsten and aluminum was formed, and the resulting slurry was aged. The aging temperature was 80°C. During the aging, one part of the sodium aluminate solution was first added, the pH value was controlled to be 13.0, one part of the β-molecular sieve slurry was added, the aging time was 0.2 hours, then the aging pH value was controlled to be 9.0, the aging time was 0.15 hours, then the pH value was controlled to be 5.0, the aging time was 0.15 hours, and the above process was repeated 5 times to complete the aging. The aged slurry was filtered, the filter cake was dried at 100°C for 10 hours, was rolled and was extruded into a strip. The extruded material was washed with deionized water at room temperature until the material was neutral. The extruded material was dried at 90°C for 8.0 hours, and the dried material was calcined at 540°C for 4 hours to obtain catalyst B. The catalyst composition and main properties are shown in Table 1.

[0046] Example 3

[0047] Ammonium metatungstate, nickel chloride and aluminum chloride were added to dissolving tank 1 containing deionized water to prepare a W, Ni, Al-containing solution, in which the concentration of W (as WO3) was 40 g / L, the concentration of Ni (as NiO) was 60 g / L, and the concentration of Al (as Al2O3) was 34.5 g / L. Ammonium molybdate was added to dissolving tank 2 containing deionized water to prepare a Mo-containing solution, in which the concentration of Mo (as MoO3) was 30 g / L, and the solution was divided into 4 equal parts by volume. The Al content of the sodium aluminate solution was 25% of the total Al (as Al2O3) in the resulting hydrocracking catalyst, and the solution was divided into 6 equal parts by volume. A β-molecular sieve slurry was prepared at a solid-to-liquid ratio of 1:3.5, and the slurry was divided into 6 equal parts by volume. The W, Ni, Al-containing solution was placed in a reaction tank, and the reaction temperature was 65°C. A mixed solution of sodium hydroxide and sodium bicarbonate having a concentration of 14 wt% and ammonia water having a concentration of 5 wt% were added to the reaction tank in a concurrent manner to perform a gelation reaction. The molar ratio of sodium hydroxide to sodium bicarbonate was 0.45:1, and the molar ratio of ammonia water to the sum of the moles of sodium hydroxide and sodium bicarbonate was 0.38. The initial pH value was controlled to be 5.3, the final pH value at the end of the reaction was adjusted to be 8.9 by increasing the pH value 4 times, and the pH value was increased by 0.9 each time. After the pH value was adjusted each time, one part of the Mo-containing solution was added, the pH value of the adjusted reaction slurry was kept constant for 11 minutes, and a precipitate slurry containing nickel, molybdenum, tungsten and aluminum was formed. The resulting slurry was aged, the aging temperature was 85°C, and the pH value was controlled to be 12.8 by adding one part of the sodium aluminate solution at the beginning of the aging. One part of the β-molecular sieve slurry was added, and the aging time was 0.2 hours. The pH value was then controlled to be 9.6 after 0.2 hours of aging, and the pH value was then controlled to be 5.3 after another 0.15 hours of aging. The above process was repeated 6 times, and the aging was completed. The aged slurry was filtered, the filter cake was dried at 110°C for 7 hours, was rolled and was extruded into a strip. The extruded material was washed with deionized water at room temperature until the material was neutral. The extruded material was dried at 80°C for 9.0 hours, and the dried material was calcined at 500°C for 5 hours to obtain catalyst C. The composition and main properties of the catalyst are shown in Table 1.

[0048] Example 4

[0049] Ammonium metatungstate, nickel chloride and aluminum chloride were added to dissolving tank 1 containing deionized water to prepare a W, Ni, Al-containing solution, in which the concentration of W (as WO3) was 50 g / L, the concentration of Ni (as NiO) was 40 g / L, and the concentration of Al (as Al2O3) was 32.6 g / L. Ammonium molybdate was added to dissolving tank 2 containing deionized water to prepare a Mo-containing solution, in which the concentration of Mo (as MoO3) was 40 g / L, and the solution was divided into 7 equal parts by volume. The Al content of the sodium aluminate solution was 32% of the total Al (as Al2O3) in the obtained hydrocracking catalyst, and the solution was divided into 4 equal parts by volume. A β-molecular sieve slurry was prepared at a solid-to-liquid ratio of 1:2.8, and the slurry was divided into 4 equal parts by volume. The W, Ni, Al-containing solution was placed in a reaction tank, and a co-current flow of a mixed solution of sodium hydroxide and sodium bicarbonate with a concentration of 11 wt% and ammonia water with a concentration of 7 wt% was added to the reaction tank to perform a gelation reaction at a reaction temperature of 68°C. The molar ratio of sodium hydroxide to sodium bicarbonate was 0.52:1, and the molar ratio of ammonia water to the sum of the moles of sodium hydroxide and sodium bicarbonate was 0.30. The initial pH value was controlled to be 5.1, and the final pH value at the end of the reaction was adjusted to be 10.0 by increasing the pH value 7 times, with each increase being 0.7. After each increase, one part of the Mo-containing solution was added, and the pH value of the adjusted reaction slurry was kept constant for 14 minutes to form a precipitate slurry containing nickel, molybdenum, tungsten and aluminum. The obtained slurry was aged at an aging temperature of 82°C. During the aging, one part of the sodium aluminate solution was first added to control the pH value to be 13.0, one part of the β-molecular sieve slurry was added, the aging time was 0.2 hours, then the aging pH value was controlled to be 9.6, the aging time was 0.15 hours, then the pH value was controlled to be 5.1, the aging time was 0.15 hours, and the above process was repeated 4 times to complete the aging. The aged slurry was filtered, the filter cake was dried at 90°C for 8 hours, was rolled and was formed into a strip. The formed product was washed with deionized water at room temperature until neutral. The dried product was calcined at 510°C for 4 hours to obtain catalyst A. The composition and main properties of the catalyst are shown in Table 1.

[0050] Comparative Example 1

[0051] Reference catalyst E was prepared according to the method disclosed in CN101239324A, the components and active metal content were the same as those in Example 1, and the molecular sieve was β molecular sieve. The specific steps were as follows: (1) chlorinated nickel, ammonium molybdate, aluminum chloride solution, and deionized water were added to a dissolving tank, the mass concentration of Ni in the solution was 52 g / L as NiO, the weight concentration of Mo was 32 g / L as MoO3, and the mass concentration of Al was 22 g / L as Al2O3, and 2000 mL of pure water was added for dilution; (2) ammonia was added under stirring until the pH value was 5.2; (3) a sodium tungstate solution was prepared, containing WO3 68 g / l, and was added to the mixture under stirring; (4) ammonia was continuously added until the pH value was 7.8; (5) the whole gelation process should be carried out at 62°C; (6) the mixture was aged at 78°C for 4 hours; before aging, β molecular sieve used in the preparation method was added, the β molecular sieve accounted for 13% of the total weight of the catalyst, the properties were shown in Table 4, and the aging was completed; (7) filtration, drying in a 100°C oven for 9 hours, rolling, and extruding into strips with a 3 mm diameter hole plate; washing with a pH = 8.8 ammonium acetate solution at room temperature; then drying in an 80°C oven for 10 hours, calcining at 540°C for 4 hours, to obtain catalyst E, the catalyst composition and properties were shown in Table 1.

[0052] Comparative Example 2

[0053] Reference catalyst F was prepared according to the method disclosed in CN106179462A, the components and active metal content were the same as those in Example 1 of the application, and the acid component was β molecular sieve. The specific process was as follows:

[0054] A mixed solution A was prepared by dissolving nickel chloride and aluminum chloride solution in deionized water, the weight concentration of NiO in the mixed solution A was 52 g / L, and the weight concentration of Al2O3 was 15.4 g / L. A mixed solution B was prepared by dissolving ammonium metatungstate, ammonium molybdate and aluminum chloride solution in deionized water, the weight concentration of WO3 in the mixed solution B was 68 g / L, the weight concentration of MoO3 was 32 g / L, and the weight concentration of Al2O3 was 6.6 g / L. The 10% (by weight) ammonia water was added into solution A under stirring, the gelation temperature was kept at 62°C, the pH value was controlled at 7.8 at the end of the process, and the gelation time was controlled at 0.8 hour, to form a slurry I containing nickel and aluminum precipitates. Deionized water was added into the reaction tank, and the 10% (by weight) ammonia water and solution B were added into the reaction tank in parallel flow, the gelation temperature was kept at 62°C, the pH value was controlled at 7.8 during the parallel flow gelation reaction process, and the gelation time was controlled at 1.0 hour, to form a slurry II containing tungsten, molybdenum and aluminum precipitates. The two kinds of slurry containing precipitates were mixed and aged, the aging time was 4.0 hours, the aging temperature was 78°C, and the pH value was controlled at 7.6, then the filter cake was hydrothermally treated under water vapor containing urea, the molar ratio of urea to total active metal atoms was 7:1, the temperature was 250°C, the pressure was 4.0 MPa, and the treatment time was 3 hours, then the filter cake was slurried, the mixture slurry was stirred uniformly with β molecular sieve suspension, filtered, the filter cake was dried at 100°C for 9 hours, rolled, and extruded into strips. The wet strips were washed with deionized water at room temperature until neutral, then the washed wet strips were dried at 80°C for 10.0 hours. The dried material was calcined at 540°C for 4 hours to obtain catalyst F. The catalyst composition, pore distribution and main properties are shown in Table 1.

[0055] Comparative Example 3

[0056] A reference agent G was prepared in the same manner as in Example 1 of the patent, except that the acidic component was Y molecular sieve. The catalyst composition and main properties are shown in Table 1.

[0057] Comparative Example 4

[0058] In the same manner as in Example 1, a reference agent H was prepared, and all sodium metaaluminate solution and β molecular sieve slurry were added at one time during the aging process of the slurry containing nickel, molybdenum, tungsten and aluminum precipitates, and a fixed value was used for the aging pH value. The specific preparation process is as follows:

[0059] Ammonium metatungstate, nickel chloride and aluminum chloride were added to dissolving tank 1 containing deionized water to prepare a W, Ni, Al-containing solution, in which the weight concentration of W as WO3 was 58 g / L, the weight concentration of Ni as NiO was 44 g / L, and the weight concentration of Al as Al2O3 was 28 g / L. Ammonium molybdate was added to dissolving tank 2 containing deionized water to prepare a Mo-containing solution, in which the weight concentration of Mo as MoO3 was 32 g / L, and the Mo-containing solution was divided into 5 equal parts by volume. The Al in the sodium aluminate solution accounted for 30% of the total Al (as Al2O3) in the obtained hydrocracking catalyst. The W, Ni, Al-containing solution was placed in a reaction tank, and a mixed solution of sodium hydroxide and sodium bicarbonate with a concentration of 12 wt% and ammonia water with a weight concentration of 6% were added into the reaction tank to perform a gelation reaction, the molar ratio of sodium hydroxide to sodium bicarbonate was 0.4:1, the molar ratio of ammonia water to the sum of sodium hydroxide and sodium bicarbonate was 0.25, the initial pH value was controlled to be 5.1, the final pH value at the end of the reaction was adjusted to be 9.1 by 5 times of pH value increase, the pH value was increased by 0.8 each time, and after the pH value was adjusted each time, one part of the Mo-containing solution was added, the pH value of the adjusted reaction slurry was kept constant for 12 minutes, a precipitate slurry containing nickel, molybdenum, tungsten and aluminum was generated, the obtained slurry was aged, the entire sodium aluminate solution and a β molecular sieve slurry were added at the beginning of the aging, the aging temperature was 76°C, the pH value was controlled to be 8.0, the aging time was 2.5 hours, and the aging was ended. The aged slurry was filtered, the filter cake was dried at 100°C for 8 hours, was rolled and was extruded into a strip. The extruded material was washed with deionized water at room temperature until neutral. The extruded material was dried at 100°C for 8.0 hours, and the dried material was calcined at 530°C for 5 hours to obtain catalyst H. The catalyst composition and main properties are shown in Table 1.

[0060] Comparative Example 5

[0061] The same as in Example 1, Reference Agent I was prepared, and the preparation process directly prepared a W, Ni, Mo, Al-containing solution to participate in the gelation reaction, and the gelation reaction was performed at a fixed pH value. The specific preparation process is as follows:

[0062] Ammonium metatungstate, ammonium molybdate, nickel chloride, and aluminum chloride were added to a dissolving tank 1 containing deionized water to prepare a solution containing W, Ni, Mo, and Al. The W concentration (as WO3) in the solution was 58 g / L, the Ni concentration (as NiO) was 44 g / L, the Mo concentration (as MoO3) was 32 g / L, and the Al concentration (as Al2O3) was 28 g / L. The Al in the sodium aluminate solution accounted for 30% of the total Al (as Al2O3) in the obtained hydrocracking catalyst, and this solution was divided into five equal portions by volume. A β-molecular sieve slurry was prepared with a solid-liquid ratio of 1:3, and this slurry was also divided into five equal portions by volume. A solution containing W, Mo, Ni, and Al was placed in a reaction vessel. A mixed solution of sodium hydroxide and sodium bicarbonate with a concentration of 12 wt% and ammonia solution with a weight concentration of 6% were added dropwise to the reaction vessel in a parallel flow to initiate a gelation reaction. The molar ratio of sodium hydroxide to sodium bicarbonate was 0.4:1, and the molar ratio of ammonia solution to the sum of the molar amounts of sodium hydroxide and sodium bicarbonate was 0.25. The initial pH value was controlled at 5.1. By adjusting the pH value five times, the final pH value was adjusted to 9.1. Each pH adjustment was made by increasing the pH value by 0.8. After adjusting the pH of the reaction slurry, it was kept constant for 12 minutes to generate a precipitate slurry containing nickel, molybdenum, tungsten, and aluminum. The resulting slurry was then aged at 76°C. During aging, one part of sodium aluminate solution was added first to control the pH at 13.3, followed by one part of β-molecular sieve slurry. After aging for 0.15 hours, the pH was controlled at 9.4 for 0.2 hours, and then the pH was controlled at 5.5 for 0.15 hours. This process was repeated 5 times to complete the aging process. The aged slurry was filtered, and the filter cake was dried at 100°C for 8 hours, rolled, and extruded into strips. The strips were washed with deionized water at room temperature until neutral. The strips were dried at 100°C for 8.0 hours, and then calcined at 530°C for 5 hours to obtain catalyst I. The composition and main properties of the catalyst are shown in Table 1.

[0063] Comparative Example 6

[0064] Similar to Example 1, precipitant A was used to carry out a precipitation reaction to prepare reference agent J.

[0065] Comparative Example 7

[0066] Similar to Example 1, precipitant B was used to carry out a precipitation reaction to prepare reference agent K.

[0067] Example 5

[0068] The present examples are catalyst activity evaluation experiments of the present application, and are compared with comparative catalysts. The present catalysts A, B, C and D and the comparative catalysts E, F, G, H, I, J and K are respectively used in a 200 mL small hydrogenation device for comparison and evaluation experiments, and the evaluation conditions are: total reaction pressure 15.7 MPa, hydrogen / oil volume ratio 1200:1, liquid hourly space velocity 1.6 h -1 -1, reaction temperature 375℃, 385℃, and the evaluation raw material is vacuum gas oil, the main properties of which are shown in Table 4, and the evaluation results are shown in Tables 5-6. From Tables 1-3, it can be seen that the present catalyst has small and uniform oxide particle size, more surface active metals, pore size concentrated in 6-10 nm, and good synergy between acidic components and hydrogenation components. The catalyst activity evaluation process conditions and the evaluation results show that, compared with the comparative catalysts, the active metal distribution, pore size distribution and oxide particle size of the present catalyst are all beneficial to improving the aromatic saturation performance, the present catalyst has high isomerization performance and high aromatic saturation performance in the treatment of heavy raw oil hydrocracking process, and can produce No. 5 industrial grade white oil and lubricating oil base oil, and the comparative catalysts cannot have high isomerization performance and high aromatic saturation performance at the same time. The present hydrocracking catalyst still has good stability and good product quality under the condition of high nitrogen content feedstock.

[0069] Table 1 Catalyst composition and properties prepared by examples and comparative examples

[0070] Catalyst No. A B C D E F NiO, wt% 22 26 30 20 26 26 WO3, wt.% 29 22 20 25 34 34 MoO3, wt.% 16 18 15 20 16 16 Al203, wt.% 20 23 23 24 11 11 SiO2, wt. % 13 11 12 11 13 13 Specific surface area, m 2 / g]] 446 438 454 458 228 377 Pore volume, mL / g 0.481 0.473 0.492 0.499 0.323 0.410 Pore distribution < 6 nm 6.14 6.92 5.12 4.63 62.47 35.16 6 nm to 10 nm 65.15 65.01 65.80 65.34 18.54 35.14 10 nm to 15 nm 15.32 15.04 14.86 15.42 10.51 16.02 > 15 nm 13.39 13.03 14.22 14.61 8.48 13.68

[0071] Table 1 Catalyst composition and properties prepared by examples and comparative examples (continued)

[0072]

[0073]

[0074] Table 2 Ratio of weight content of surface active metal oxide to weight content of bulk active metal oxide of catalyst

[0075] Catalyst No. A B C D E F Table phase I W+Ni Bulk phase I W+Ni ]] 5.11 5.03 5.45 5.57 0.92 1.02 Table phase I Mo Ni Bulk phase I Mo Ni ]]> ​​ 4.21 4.14 4.36 4.48 1.03 0.99

[0076] Table 2 (continued)

[0077] Catalyst No. G H I J K Table phase I W+Ni Bulk phase I W+Ni ]]> 5.04 3.22 3.38 1.09 0.96 Table phase I Mo+Ni Bulk phase I Mo+Ni ]]> 4.16 1.75 1.89 1.05 0.90

[0078] Table 3 Oxide particle average size and particle size distribution of catalysts obtained by examples

[0079]

[0080]

[0081] Table 3 (continued) Average particle size and particle size distribution of the catalyst oxide particles obtained in each example

[0082] Catalyst No. G H I J K Oxide particle average diameter, nm 10.1 19.5 17.1 15.9 30.1 Oxide particle size distribution, % Particle size less than 8 nm 8.41 8.91 7.51 47.23 1.64 Particle size 8 nm to 12 nm 79.98 25.45 29.42 20.98 5.18 Particle size greater than 12 nm 11.61 65.64 63.07 31.79 93.18

[0083] Table 4 Main properties of the feedstock oils

[0084]

[0085] Table 5 Evaluation results of the catalysts of the examples and comparative examples (operation for 250 hours)

[0086]

[0087]

[0088] Table 5 (continued) Evaluation results of the catalysts of the examples and comparative examples (operation for 250 hours)

[0089] Catalyst G H I J K Reaction temperature, °C 375 375 375 375 375 Nitrogen content in feed, pg / g 118 118 118 118 118 82-132 °C heavy naphtha Aromatics potential, wt% 58.6 60.8 60.5 60.2 59.5 132-282 °C marine gas oil Smoke point, mm 29.6 25.1 25.3 23.0 23.5 Aromatics, v% 1.7 12.5 12.4 18.8 17.3 282-370 °C diesel Pour point, °C 3 -8 -7 -8 -8 Aromatics, wt% 2.0 12.6 10.8 14.0 12.9 > 370 °C tail oil BMCI value 5.4 14.4 15.8 24.1 23.4 Viscosity index 123 103 105 92 96

[0090] Table 6 Evaluation results of the catalysts of the examples and comparative examples (operation for 2000 hours)

[0091]

[0092]

[0093] Table 7 Properties of the β molecular sieves in the examples and comparative examples

[0094] Si / Al molar ratio 80.5 Specific surface area, m 2 / g]] 621 Pore volume, mL / g 0.55 Infrared total acid, mmol / g 0.43 Na2O, wt.% 0.080

[0095] Table 8 Properties of the Y-type molecular sieves used in the present application

[0096]

[0097]

Claims

1. A process for the preparation of a body phase hydrocracking catalyst, characterized in that The method comprises the following steps: (1) adding a W, Ni and Al-containing solution into a gelation reaction tank, and adding a precipitant A and a precipitant B into the reaction tank in parallel to perform a gelation reaction; during the gelation reaction, the pH value is controlled to gradually increase from an initial value to a final value, and a molybdenum-containing solution is added after each increase; the number of increases n is 2-10; (2) continuously performing n times of aging on the slurry obtained in step (1), adding 1 / n sodium metaaluminate solution and 1 / n beta molecular sieve slurry during each aging process, uniformly mixing, and filtering the slurry after aging to obtain a solid material, wherein n is an integer of 2-8; wherein each aging process adopts a pH value gradually decreasing aging process; (3) drying, shaping, washing, drying and calcining the solid material obtained in step (2) to obtain a hydrocracking catalyst; wherein the precipitant A in step (1) is a mixed solution of sodium hydroxide and sodium bicarbonate, and the precipitant B is ammonia water. In the W, Ni and Al-containing solution in step (1), the weight concentration of W in the form of WO3 is 5-140 g / L, the weight concentration of Ni in the form of NiO is 5-130 g / L, and the weight concentration of Al in the form of Al2O3 is 2-90 g / L.

2. The method of claim 1, wherein: In step (1), the concentration of the mixed solution of sodium hydroxide and sodium bicarbonate is 7wt%-20wt%, the molar ratio of sodium hydroxide to sodium bicarbonate is 0.2:1-0.8:1, the concentration of ammonia water is 4wt%-8wt%, and the molar ratio of ammonia water in the form of NH3 to the mixed solution of sodium hydroxide and sodium bicarbonate in the form of sodium hydroxide and sodium bicarbonate is 0.1:1-0.45:

1.

3. The method of claim 1, wherein: In step (1), at the beginning of the gelation reaction, the initial pH value is controlled to be 5.0-6.5, and the required time is 0.05-0.4 hours; the final pH value is 8.0-10.5, the gelation reaction temperature is 40-90 DEG C, and the gelation reaction time is 0.3-5.0 hours.

4. The method of claim 1, wherein: In step (1), after each increase, the pH value is kept constant for 0.05-0.5 hours, and the pH value increase amplitude of each time is not greater than the pH value increase amplitude of the previous time.

5. The method of claim 1, wherein: In the molybdenum-containing solution in step (1), the weight concentration of Mo in the form of MoO3 is 10-150 g / L; the molybdenum-containing solution is added in several times according to the number of pH value increases, the volume of the molybdenum-containing solution added each time is the same or different, and the total amount of the molybdenum-containing solution is determined according to the composition of the catalyst.

6. The method of claim 1, wherein: In step (2), the weight concentration of Al in the form of Al2O3 in the sodium metaaluminate solution is 5-75 g / L; the sodium metaaluminate solution is divided into 2-8 parts in volume according to the number of additions; and the beta molecular sieve slurry is divided into 2-8 parts in volume according to the number of additions.

7. The method of claim 1, wherein: In step (2), the aging temperature is 60-98 DEG C.

8. The method of claim 1, wherein: ​ 9. The method of claim 1, wherein: The pH stepwise decreasing aging process in step (2) is as follows: the reaction slurry is dropped into 1 / n sodium metaaluminate solution for pH adjustment, the pH is controlled at 11.5-13.5, 1 / n beta molecular sieve slurry is added, and aging is performed for 0.05-0.5 hours; then the pH is adjusted to 8.5-10.5, and aging is performed for 0.05-0.5 hours; finally, the pH is adjusted to 4.0-6.5, and aging is performed for 0.05-0.5 hours, wherein n is an integer of 2-8.

10. The method of claim 1, wherein: In step (2), the Al added in the sodium metaaluminate solution accounts for 5%-50% of the total Al in the obtained hydrocracking catalyst in terms of Al2O3.

11. The method of claim 1, wherein: The β molecular sieve in step (2) has the following properties: the molar ratio of silicon oxide to aluminum oxide is 30-90, the specific surface area is 430-780 m 2 / g, the pore volume is 0.30-0.90 cm 3 / g, and the infrared acid acid amount is 0.10-0.45 mmol / g; the β molecular sieve slurry is a mixture of the β molecular sieve and deionized water stirred uniformly, and the solid-liquid mass ratio is 1:1.2-1:

4.

12. A body phase hydrocracking catalyst prepared by the process of any one of claims 1 to 11. The hydrocracking catalyst comprises a hydrogenation active metal component, amorphous alumina and beta molecular sieve; the pore size distribution of the hydrocracking catalyst is as follows: the pore volume of pores with a diameter of 6 nm or less accounts for 2%-14% of the total pore volume, the pore volume of pores with a diameter of 6-10 nm accounts for 52%-73% of the total pore volume, the pore volume of pores with a diameter of 10-15 nm accounts for 10%-25% of the total pore volume, and the pore volume of pores with a diameter of 15 nm or more accounts for 6%-23% of the total pore volume; the molar ratio of W / Mo is 1:13-10:1, and the molar ratio of Ni / (Mo+W) is 1:14-13:1; wherein the ratio of the sum of the weight contents of the surface phase active metal components WO3 and NiO to the sum of the weight contents of the bulk phase active metal components WO3 and NiO is 2.4:1-6.5:1, and the ratio of the sum of the weight contents of the surface phase active metal components MoO3 and NiO to the sum of the weight contents of the bulk phase active metal components MoO3 and NiO is 2.3:1-5.6:

1.

13. The bulk hydrocracking catalyst of claim 12, wherein: The average particle size of tungsten, molybdenum and nickel active metal oxide microparticles is 8-12 nm; the particle size distribution of the tungsten, molybdenum and nickel active metal oxide microparticles is as follows: the number of microparticles with a particle size of less than 8 nm accounts for 3%-15% of the total number of microparticles, the number of microparticles with a particle size of 8-12 nm accounts for 70%-90% of the total number of microparticles, and the number of microparticles with a particle size of more than 12 nm accounts for 6%-18% of the total number of microparticles.

14. Use of a bulk phase hydrocracking catalyst prepared by the method of any one of claims 1-11 in a hydrocracking process of a feedstock of No. 5 industrial grade white oil and high viscosity index lubricating oil base oil.

15. The use according to claim 14, characterized in that: The nitrogen content in the feed of the hydrocracking process is less than 150 µg / g, and is more than 10 µg / g.

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