Preparation method of hydrotreating catalyst

Abstract

The present invention discloses a method for preparing a hydrorefining catalyst. The method comprises the following contents: (1) a sodium hydroxide solution, a silicon-containing alkaline solution, a sodium molybdate solution and a Ni-containing solution are subjected to a gelling reaction, and after the reaction, a first aging is performed to obtain a first slurry; (2) water and an oily liquid are added to a reactor, and then a Ni- and Al-containing solution, a sodium tungstate solution, a sodium phosphate solution and the first slurry are added to the reactor in parallel to perform a gelling reaction, and after the reaction, a second aging is performed to generate a second slurry; (3) the second slurry is subjected to aging, and after the aging is completed, solid-liquid separation is performed, and the solid phase is subjected to drying and molding processes to obtain a molded product; (4) the molded product is subjected to a desalting treatment, washing, drying and roasting to obtain a hydrorefining catalyst with a core-shell structure. The catalyst of the present invention has low preparation cost, a clean and pollution-free preparation process, can avoid excessive cracking of diesel fractions, and has good raw material adaptability, and can process inferior distillate oil raw materials.

Description

Technical Field

[0001] The invention relates to a method for preparing a hydrorefining catalyst, in particular to a method for preparing a bulk hydrorefining catalyst. The hydrorefining catalyst is suitable for processes such as hydrodesulfurization and denitrogenation of distillate oil. Background Art

[0002] In order to improve the competitiveness of catalysts in the market and meet the increasingly stringent environmental regulations, it is urgent to use relatively low-priced raw materials to prepare catalysts and use nitrogen-free raw materials in the catalyst preparation process to solve the problem of "ammonia nitrogen" and NO from the source. X pollution problem and reduce the cost of catalyst preparation.

[0003] Bulk hydrogenation catalysts are currently the catalysts with the highest hydrogenation activity centers. Bulk catalysts prepared by existing methods have smaller pore volumes and pore sizes, resulting in reactions on the catalyst surface that is inaccessible to reactant molecules. At the same time, the smaller pore volume and specific surface area cause the high content of active metals in the bulk catalyst to accumulate excessively on the catalyst surface, reducing the generation of active phases, lowering the activity of the catalyst, and also affecting the utilization rate of the active metals in the catalyst, thereby increasing the cost of using the catalyst.

[0004] The use of impregnation and kneading methods to prepare catalysts results in high catalyst preparation costs and large wastewater treatment costs because relatively low-priced sodium metal salt raw materials cannot be used. The coprecipitation method can use relatively low-priced sodium raw materials to prepare catalysts, which greatly reduces the catalyst preparation costs and wastewater treatment costs. However, the introduction of a large number of sodium ions makes it difficult to remove sodium ions from the catalyst. Even if the number of washings is increased (the increase in the number of washings will reduce the crushing strength of the catalyst), only the sodium ions on the surface of the catalyst can be removed. A large number of sodium ions still exist in the precipitated material. The residual sodium ions lead to poor adhesion of the material. The sodium ions that are not removed are not conducive to the formation of the catalyst pore structure, resulting in a small pore volume and pore size of the catalyst.

[0005] The existing co-precipitation method mostly uses ammonia water as a precipitant and nitrogen-containing soluble salts as raw materials. The distribution of hydrogenation active metals and the interaction between different hydrogenation active metals are improved by changing the precipitation method and gelation conditions. However, it does not solve the problems of small pore volume and specific surface area of ​​bulk catalysts, small pore size of catalysts (pore size distribution is mainly concentrated below 8nm), large metal oxide particles in catalysts, and "ammonia nitrogen" and NO in catalyst preparation. X There are many problems such as pollution and high cost. Especially when using cheaper sodium-containing raw materials, the gel-forming materials are loose and difficult to shape, and the catalyst has many small pores.

[0006] CN106179474B discloses a highly active bulk hydroprocessing catalyst and a preparation method thereof. A two-step method of positive addition and parallel flow is used to prepare a precipitate containing W, Ni and Mo, and a microporous and mesoporous composite molecular sieve is added. The catalyst has a high surface active metal content, a more uniform active metal dispersion, good coordination between active metals, and a high active metal utilization rate. At the same time, the catalyst has a reasonable pore structure, high mechanical strength, and high hydrodesulfurization and hydrodenitrogenation activity. The catalyst prepared by this method contains a molecular sieve, and a strong acidity can improve the ultra-deep desulfurization activity of the catalyst, but a cracking reaction occurs, which reduces the yield of the diesel product.

[0007] CN102451706A discloses a method for preparing a hydrogenation catalyst composition, which uses a sodium aluminate solution, a mixed solution containing Ni and W component salts and CO2 gas for parallel flow reaction to generate a precipitate. CN110038581A discloses a method for preparing a hydrogenation refining catalyst. The hydrogenation refining catalyst is prepared by two-step precipitation, using sodium tungstate alkaline solution and sodium molybdate alkaline solution as precipitants for precipitation, respectively. Both methods use a large amount of sodium ion-containing salt as raw material for precipitation reaction, but the precipitate generated by this method contains a certain amount of sodium ions, the metal oxide particles are relatively large, and the residual sodium ions lead to poor adhesion of the material. The residual sodium ions also make the pore volume and specific surface area of ​​the catalyst small.

[0008] CN106513006A discloses a method for preparing a bulk phase hydrorefining catalyst, which comprises: pre-dispersing a Ni-containing compound with deionized water under an ultrasonic environment, then adding a Mo-containing compound to form a Ni-Mo fine grain structure, then adding a W-containing compound and a complexing agent for hydrothermal reaction, and then kneading and extruding the obtained active component powder with aluminum hydroxide dry glue, drying and calcining to obtain a catalyst. The catalyst prepared by the method of the present invention has uniform dispersion between different active phase grains, W source is embedded in the Ni-Mo skeleton structure, Ni-W active phase is easily wrapped by Ni-Mo active phase at the microscopic level, and is not an oxide core-shell structure at the macroscopic level, the pore volume is small, the effective active phase is not much, the metal oxide particles are large, and the removal efficiency of complex sulfur-containing compounds with high nitrogen content is limited. Summary of the invention

[0009] In view of the deficiencies of the prior art, the present invention provides a method for preparing a hydrorefining catalyst. The hydrorefining catalyst is a bulk hydrogenation catalyst with a core-shell structure, has a large pore volume and pore diameter, has high hydrodesulfurization and hydrodenitrogenation reaction performance, has low preparation cost, and a clean and pollution-free preparation process, can avoid excessive cracking of diesel fractions, and has good raw material adaptability, and can process inferior distillate oil raw materials.

[0010] The preparation method of the hydrotreating catalyst of the present invention comprises the following contents:

[0011] (1) reacting a Ni-containing solution, a sodium molybdate solution and a sodium hydroxide solution in parallel, stopping the reaction for 5 to 40 minutes when the volume of the Ni-containing solution is 1 / 5 to 1 / 2, then adding a silicon-containing alkaline solution to continue the gelling reaction, and performing a first aging after the reaction to obtain a first slurry containing Ni, Si and Mo;

[0012] (2) adding water and oily liquid into the reactor, and then adding Ni, Al-containing solution, sodium tungstate solution, sodium phosphate solution and the first slurry into the reactor in parallel to carry out a second gelling reaction, and then undergoing a second aging after the reaction to generate a second slurry;

[0013] (3) aging the second slurry, separating the solid from the liquid after aging, and drying and molding the solid phase to obtain a molded product;

[0014] (4) The formed product is desalted, washed, dried and calcined to obtain a core-shell structured hydrotreating catalyst.

[0015] In the method of the present invention, the weight concentration of the sodium hydroxide solution in step (1) is 5% to 30%. Those skilled in the art can determine the amount of the sodium hydroxide solution according to actual needs.

[0016] In the method of the present invention, the silicon-containing alkaline solution in step (1) can be one or more of water glass, silica sol, etc. The weight concentration of Si in the silicon-containing alkaline solution calculated as SiO2 is 5-90 g / L, preferably 6-85 g / L.

[0017] In the method of the present invention, in the sodium molybdate solution in step (1), the weight concentration of Mo in terms of MoO3 is 5 to 110 g / L, preferably 10 to 100 g / L.

[0018] In the method of the present invention, in the Ni-containing solution described in step (1), the weight concentration of Ni in terms of NiO is 5 to 120 g / L, preferably 10 to 110 g / L; when preparing the Ni-containing solution, the nickel source generally used can be one or more of nickel sulfate, nickel nitrate, and nickel chloride.

[0019] In the method of the present invention, the conditions of the gelling reaction in step (1) are as follows: the reaction temperature is 30-90°C, preferably 40-85°C, the pH value is 7.0-11.0, preferably 7.2-10.0, and the gelling time is 0.2-2.5 hours, preferably 0.3-2.0 hours.

[0020] In the method of the present invention, the first aging conditions in step (1) are as follows: the aging temperature is 60-90° C., preferably 65-85° C., the pH value during aging is 7.0-11.0, preferably 7.2-10.5, and the aging time is 0.3-2.5 hours, preferably 0.5-2.0 hours.

[0021] In the method of the present invention, in step (1), the weight of the introduced Ni accounts for 30% to 80%, preferably 35% to 78%, of the total Ni weight in the hydrotreating catalyst obtained in step (4), and the remaining Ni in the catalyst is introduced in step (2).

[0022] In the method of the present invention, in the Ni and Al-containing solution of step (2), the weight concentration of Ni calculated as NiO is 5 to 110 g / L, preferably 10 to 100 g / L, and the weight concentration of Al calculated as Al2O3 is 2 to 95 g / L, preferably 5 to 85 g / L. When preparing the Ni and Al-containing solution, the nickel source generally used may be one or more of nickel sulfate, nickel nitrate, and nickel chloride, and the aluminum source may be one or more of aluminum nitrate, aluminum sulfate, aluminum chloride, and aluminum acetate.

[0023] In the method of the present invention, in the sodium tungstate solution of step (2), the weight concentration of W in terms of WO3 is 4 to 140 g / L, preferably 6 to 120 g / L;

[0024] In the method of the present invention, the weight concentration of P as P2O5 in the sodium phosphate solution described in step (2) is 2-70 g / L, preferably 3-65 g / L.

[0025] In the method of the present invention, the volume ratio of the water added in step (2) to the first slurry is 0.1:1 to 3:1.

[0026] In the method of the present invention, the oily liquid in step (2) is unsaturated higher fatty acid glyceride (vegetable oil), preferably one or more of peanut oil, rapeseed oil, cottonseed oil, sunflower oil, soybean oil, corn oil, tea oil, and olive oil. The volume ratio of the oily liquid to water is 1:60 to 1:4, preferably 1:40 to 1:6.

[0027] In the method of the present invention, the conditions of the second gelling reaction in step (2) are as follows: the reaction temperature is 30-90°C, preferably 40-85°C, the pH value is initially controlled to be 10.0-14.0, preferably 10.5-13.5, the final pH value is 7.0-8.5, preferably 7.2-8.3, and the gelling reaction time is 0.5-6.0 hours, preferably 0.6-5.0 hours. Preferably, the pH value can be adjusted from the initial value to the final pH value by a stepwise downward adjustment method, and the stepwise downward adjustment method is to adjust the pH value to the desired value of the time, and keep the pH value of the reaction slurry constant until the next downward adjustment begins, and the number of downward adjustments is 2-10 times, preferably 2-8 times. Preferably, it is preferably kept constant for 0.1-1.2 hours after each downward adjustment. The amplitude of each downward adjustment can be the same or different, and it is preferred that the amplitude of the pH reduction in the current downward adjustment is equal to or less than the amplitude of the pH reduction in the previous downward adjustment. The time used for each downward adjustment process is from the start of the current downward adjustment to the start of the next downward adjustment, and further, is the sum of the time used for each pH value downward adjustment and the time when the pH value is constant. The time used for each downward adjustment process can be the same or different, and preferably the same time.

[0028] In the method of the present invention, the second aging conditions in step (2) are as follows: aging temperature is 40 to 90° C., aging time is 1 to 5 hours, and pH value is 7.0 to 11.0. The aging is generally carried out under stirring conditions.

[0029] The aging conditions in step (2) are preferably carried out as follows: the first step is normal pressure aging: the aging temperature is 30-90°C, preferably 40-80°C, the aging time is 1-6 hours, preferably 1.2-5 hours, and the pH value is 6.5-10.0, preferably 7.0-9.0; the second step is high pressure aging: the temperature is 100-195°C, preferably 100-190°C, the time is 0.1-3.5 hours, preferably 0.3-2.8 hours, the pressure is not less than 10 MPa, preferably 10-15 MPa, and the pH value is 10.0-13.0, preferably 10.0-12.5. The mild conditions in the above-mentioned aging process are more conducive to the formation of uniform particle size. During the aging process in a closed environment, the material phase structure has generated a regular body in the first step of aging. In a closed environment, under the action of higher temperature and pressure, the microscopic morphology of the material changes, and the material phase changes from a regular body to an irregular body formed by irregular flake accumulation. This structural change causes the sodium ions inside the phase to transfer to the surface of the phase, which is more conducive to the next step of desalination treatment, and is also conducive to increasing the specific surface area of ​​the bulk catalyst, improving the pore structure, exposing more active metals to the catalyst surface, and generating more hydrogenation active centers on the catalyst surface.

[0030] In the method of the present invention, the solid-liquid separation described in step (3) is generally carried out by filtration, centrifugation, etc. The drying temperature described in step (3) is 50 to 140°C, and the drying time is 0.5 to 24 hours. The molding process described in step (3) is well known in the field of catalyst preparation. An extrusion aid and a peptizing agent are generally added during the extrusion molding process. The extrusion aid can be one or more of sesbania powder, carbon black, graphite powder or cellulose, etc. The peptizing agent is generally an acid solution containing one or more of hydrochloric acid, sulfuric acid, acetic acid, etc. The amount of the extrusion aid accounts for 1wt% to 10wt% of the total material dry basis. The catalyst of the present invention can be prepared into the shape of sheets, spheres, cylindrical strips and special-shaped strips (three-leaf clover, four-leaf clover) as needed.

[0031] In the method of the present invention, the desalination treatment process described in step (4) is: first curing, and then washing to remove the salt precipitated on the surface of the molded product, the curing conditions are a temperature of 5 to 100°C, preferably a temperature of 10 to 90°C, and a time of 10 to 100 hours, preferably 24 to 90 hours.

[0032] In the method of the present invention, the desalination treatment described in step (4) is preferably carried out in the following manner: in the first stage, the temperature is 60 to 90° C., and the curing time is 5 to 60 hours, preferably 8 to 55 hours, so that the hydrated sodium ions are precipitated and vacancies are retained; in the second stage, the temperature is 10 to 30° C., and the time is 1 to 48 hours, preferably 2 to 42 hours, so that the vacancies are retained and shrunk, so that the pore volume of the catalyst is increased and the catalyst has good mechanical strength, and then the precipitated salt is washed away. The washing process can use a solvent with good solubility for sodium salts, such as water and ethanol.

[0033] In the method of the present invention, the washing, drying and roasting in step (4) can be carried out under conventional conditions in the art. The drying conditions are as follows: drying at 40-150°C for 1-48 hours, preferably drying at 50-120°C for 4-36 hours. The roasting conditions are as follows: roasting at 350-650°C for 1-24 hours, preferably roasting at 400-600°C for 2-12 hours. Washing is generally carried out with deionized water or ethanol solution until neutral.

[0034] The hydrorefining catalyst of the present invention is a bulk hydrogenation catalyst of a core-shell structure, comprising composite amorphous oxide particles, wherein the core phase is an amorphous composite oxide containing molybdenum, nickel and silicon, and the shell phase is an amorphous composite oxide containing tungsten, nickel, phosphorus and aluminum; the catalyst of the present invention can be in the form of flakes, spheres, cylindrical bars and shaped bars (three-leaf clover, four-leaf clover) as needed, preferably cylindrical bars and shaped bars (three-leaf clover, four-leaf clover). The average particle size of the catalyst particles is 8-13nm; the particle size distribution of the catalyst particles is as follows: the number of particles with a particle size less than 7nm accounts for 2%-15% of the total number of particles, the number of particles with a particle size of 7nm-13nm accounts for 66%-88% of the total number of particles, and the number of particles with a particle size greater than 13nm accounts for 3%-21% of the total number of particles.

[0035] In the catalyst of the present invention, based on the mass of the core-shell structured composite oxide particles, the core phase accounts for 20% to 90%, preferably 25% to 88%, and the shell phase accounts for 10% to 80%, preferably 12% to 75%.

[0036] In the catalyst of the present invention, the molar ratio of molybdenum to nickel atoms in the core phase is 1:28-12:1, preferably 1:22-10:1, and the silicon content in terms of SiO2 accounts for 2%-38% of the mass of the hydrorefining catalyst, preferably 4%-36%.

[0037] In the catalyst of the present invention, the molar ratio of tungsten to nickel atoms in the shell phase is 1:22~8:1, preferably 1:20~5:1, the aluminum content calculated as Al2O3 accounts for 2%~25% of the mass of the hydrorefining catalyst, preferably 5%~22%, and the phosphorus content calculated as P2O5 accounts for 3%~20% of the mass of the hydrorefining catalyst, preferably 5%~18%.

[0038] In the catalyst of the present invention, the mass of NiO in the core phase accounts for 30% to 80% of the total mass of NiO in the hydrorefining catalyst, and the mass of NiO in the shell phase accounts for 20% to 70% of the total mass of NiO in the hydrorefining catalyst.

[0039] The Na2O content in the catalyst of the present invention is less than 0.12%, preferably less than 0.1%.

[0040] In the catalyst of the present invention, the properties of the hydrotreating catalyst are as follows: the specific surface area is 180~700m 2 / g, pore volume is 0.30~0.90mL / g. The pore size distribution of the bulk hydrorefining catalyst of the present invention is as follows: the pore volume occupied by pores with a diameter of less than 4nm accounts for 1%~10% of the total pore volume, the pore volume occupied by pores with a diameter of 4~10nm accounts for 12%~40% of the total pore volume, the pore volume occupied by pores with a diameter of 10~15nm accounts for 22%~56% of the total pore volume, and the pore volume of pores with a diameter of more than 15nm accounts for 18%~45% of the total pore volume; the preferred pore size distribution is as follows: the pore volume occupied by pores with a diameter of less than 4nm accounts for 2%~8% of the total pore volume, the pore volume occupied by pores with a diameter of 4~10nm accounts for 14%~36% of the total pore volume, the pore volume occupied by pores with a diameter of 10~15nm accounts for 24%~54% of the total pore volume, and the pore volume of pores with a diameter of more than 15nm accounts for 20%~42% of the total pore volume.

[0041] The bulk phase hydrorefining catalyst of the present invention is used in the diesel hydrorefining reaction. The diesel hydrorefining reaction conditions are as follows: the reaction temperature is 330-400°C, the reaction pressure is 2.5-12MPa, the hydrogen-oil volume ratio is 250:1-1200:1, and the liquid hourly volume space velocity is 0.3-5.0h -1 .

[0042] Compared with the prior art, the present invention has the following advantages:

[0043] 1. The method of the present invention first prepares molybdenum-nickel-silicon aged slurry, and then adds it to a reactor containing water and greasy liquid in parallel with nickel-aluminum mixed solution, sodium tungstate solution and sodium phosphate for a second gelation, so that tungsten and nickel are uniformly and orderly precipitated on molybdenum-nickel grains, thereby forming tungsten-nickel-coated molybdenum-nickel nanoparticles, and the core-shell composite oxide particles have good dispersibility. In the first gelation reaction, when the composite oxide of tungsten, nickel and silicon is formed, the number of acidic centers at the junction of the core and shell is better controlled by adjusting the way of adding silicon. In the second gelation reaction, when the composite oxide of tungsten, nickel and aluminum is formed, sodium phosphate is used as a precipitant to gel by a pH value decreasing method, which can make the size of the core-shell composite oxide particles more uniform. At the same time, the intermediate formed between the auxiliary agent P and the hydrogenation active metal at the junction of the core and shell is conducive to improving the interaction between the hydrogenation active metal and the acidic center at the junction of the core and shell. The hydrofining catalyst prepared in this way is suitable for the hydrofining reaction of heavy distillate oil (such as diesel), especially conducive to deep hydrodesulfurization and denitrification, and can also avoid reducing the diesel yield.

[0044] 2. In the method of the present invention, a low-cost catalyst is prepared by a clean method. Since a soluble sodium salt is used as a raw material, a large amount of sodium ions are contained in the precipitate after gelation. The presence of a large amount of sodium ions causes the catalyst to have a small pore volume and is not easy to form. The inventor retains the sodium salt in the material during the forming process, and then desalts the formed material to remove the precipitated sodium salt. In this process, due to the occupying effect of the sodium salt during the forming process, the vacancies after sodium removal are more conducive to the formation of the catalyst pore structure, the pore distribution moves toward the macropore direction, the pore volume and pore size of the catalyst increase, and the diffusion performance of the catalyst is improved, which solves the problem that the catalyst has a small pore volume and is not easy to form when the prior art uses clean raw materials to prepare bulk catalysts. In the catalyst preparation process, the number of washing times in the conventional catalyst preparation process is reduced by desalting treatment, and the amount of water is reduced. Through the comprehensive control of the preparation steps and preparation conditions, the core-shell composite oxide structure obtained is more conducive to the desalting of the material.

[0045] 3. The hydrofining catalyst of the present invention improves the distribution state of active metals at the nano level, that is, it is mainly composed of composite oxide particles containing molybdenum, nickel and silicon coated with composite oxide containing tungsten, nickel and aluminum. This coating structure is different from the structure at the macro level (such as millimeter level). The structure of the catalytic material is controlled at the micro level, so that the overall performance of the catalyst can be broken through, the hydrodesulfurization performance of the catalyst is improved, and a certain amount of acid centers are formed at the junction of the core-shell structure of the catalyst, so that the catalyst can eliminate steric hindrance while performing hydrodesulfurization reaction, and reduce the occurrence of side reactions such as excessive cracking, so that when the sulfur and nitrogen-containing distillate oil raw materials (especially the distillate oil raw materials containing sulfur and nitrogen that are difficult to remove) contact with the hydrofining catalyst of the present invention, the desulfurization and denitrification activities are significantly improved, and at the same time, the cracking reaction of the diesel fraction is reduced, and the diesel yield is avoided. In addition, the catalyst of the present invention can reduce the content of active metals while ensuring the desulfurization and denitrification activities, thereby reducing the preparation cost of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is the TEM image of catalyst D obtained in Example 2. DETAILED DESCRIPTION

[0047] In the present invention, the specific surface area and pore volume are measured by low temperature liquid nitrogen adsorption method, and the mechanical strength is measured by lateral pressure method. The specific surface area, pore volume and pore size distribution are measured by ASAP-2405 BET nitrogen adsorption instrument; the crushing strength of the catalyst is measured by ZQJ-2 intelligent particle strength testing machine.

[0048] In the present invention, in the core-shell composite oxide particles, the metal content in the composite oxide in the core and the shell and the thickness of the shell are measured by TEM transmission electron microscope (Japan JSM-2100). Among them, the method for determining the metal content in the composite oxide in the core and the shell is as follows: the core-shell composite oxide particles are uniformly mixed with liquid epoxy resin, and then an appropriate amount of curing agent is added, and the mixture is heated and cured after being stirred evenly to form solid particles. The solid particles are cut into thin slices with a thickness of 5-20nm by an ultrathin slicer, and the obtained slices are placed in a transmission electron microscope for observation to find a core-shell structure (cross section) with a clear interface. The diameter of the electron beam is adjusted by a condenser so that its diameter basically covers the outline of the entire core-shell structure, and the energy spectrum EDS spectrum is collected to record the intensity of the main energy peak, which corresponds to the actual content of each element in the known feed and the energy peak intensity of each element. The electron beam diameter is adjusted so that it is smaller than or close to the core or shell size, and the metal content in the composite oxide in the core and the shell at this time is calculated according to the energy peak intensity corresponding to the element, compared with the peak intensity under full coverage and the corresponding actual value. In the core-shell structure, the shell thickness is identified and measured from the transmission electron microscope image, and the ratio of the shell thickness to the total core-shell thickness is the average value obtained by measuring 40 to 100 core-shell particles.

[0049] In the present invention, wt% refers to mass fraction, and v% refers to volume fraction.

[0050] Example 1

[0051] Add nickel chloride to dissolution tank 1 filled with deionized water to prepare a solution containing Ni, and the weight concentration of Ni in the Ni solution as NiO is 28g / L. Add nickel chloride and aluminum chloride solutions to dissolution tank 2 filled with deionized water to prepare solutions containing Ni and Al, and the weight concentration of Ni in the Ni and Al solution as NiO is 24g / L, and the weight concentration of Al as Al2O3 is 26g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni-containing solution used is 14:12. The Ni-containing solution, the sodium hydroxide solution (weight concentration of 12%) and the sodium molybdate solution (the weight concentration of Mo in terms of MoO3 is 36g / L) are dropped into the reaction tank 1 for the first gelation reaction. When the remaining volume of the Ni-containing solution is 1 / 3, the gelation is stopped and allowed to stand for 15 minutes. Then the remaining Ni-containing solution, the sodium molybdate solution and the water glass (the weight concentration of SiO2 is 26g / L, the sodium hydroxide solution (weight concentration is 12%) are continued to be gelled until the reaction is completed. The gelation temperature is maintained at 62°C. At the end of the reaction, the pH value is controlled at 7.8, and the gelation time is controlled at 1.2 hours. After the reaction is completed, aging is carried out at 78°C, the aging pH value is controlled at 7.5, and the aging is carried out for 1.8 hours to obtain the first slurry. First, 800mL of deionized water and 60mL of rapeseed oil are added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution is 20g / L in terms of P2O5), the first slurry, the Ni- and Al-containing solution and the sodium tungstate solution are added. The liquid (W weight concentration in terms of WO3 is 40 g / L) is added to the reaction tank 2 for the second gelation reaction. The gelation temperature is maintained at 60°C, and the initial pH value is controlled at 13.0. The pH value is adjusted down 6 times to adjust the final pH value to 7.6 at the end. The pH value is adjusted down by 0.9 each time. After each adjustment to the adjusted value, the adjusted pH value of the reaction slurry is kept constant for 10 minutes. After the second gelation reaction is completed, aging begins. The aging temperature is 78°C and the pH value is controlled at 8.0. , aging time 2.5 hours, to obtain the second slurry. The aged slurry was filtered, the filter cake was dried at 100°C for 7 hours, rolled, and extruded into a clover shape. After the formed strips were cured at 70°C for 50 hours, the temperature was reduced to 20°C and continued to cure for 30 hours. Washed with deionized water at room temperature until neutral. The wet strips were then dried at 100°C for 12.0 hours, and the dried material was calcined at 500°C for 4 hours to obtain catalyst A. The catalyst composition and main properties are shown in Table 1.

[0052] Example 2

[0053] Nickel chloride is added to a dissolution tank 1 filled with deionized water to prepare a Ni-containing solution, wherein the weight concentration of Ni in the Ni-containing solution as NiO is 48 g / L. Nickel chloride and aluminum chloride solutions are respectively added to a dissolution tank 2 filled with deionized water to prepare Ni- and Al-containing solutions, wherein the weight concentration of Ni in the Ni- and Al-containing solution as NiO is 20 g / L, and the weight concentration of Al as Al2O3 is 24 g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni- and Al-containing solution used is 24:10. The Ni-containing solution is placed in reaction tank 1, and sodium hydroxide solution (weight concentration of 12%) and sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 40 g / L) are dripped into reaction tank 1 to carry out the first gelling reaction. When the remaining volume of the Ni-containing solution is 2 / 5, the gelling is stopped and allowed to stand for 18 minutes. Then the remaining Ni-containing solution, sodium molybdate solution and water glass (weight concentration of SiO2 is 28 g / L) and sodium hydroxide solution (weight concentration is 12%) are continued to be gelled until the reaction is completed. The gelling temperature is maintained at 65°C. At the end of the reaction, the pH value is controlled at 8.4 and the gelling time is controlled at 1.6 hours. After the reaction is completed, aging is carried out at a temperature of 78°C and a pH value of 8.1. The aging is carried out for 1.5 hours to obtain the first slurry. First, 600 mL of deionized water and 70 mL of corn oil were added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 16 g / L in terms of P2O5), the first slurry, the solution containing Ni and Al, and the sodium tungstate solution (the weight concentration of W in terms of WO3 was 24 g / L) were added to the reaction tank 2 for the second gelation reaction. The gelation temperature was maintained at 68°C, and the pH value was initially controlled to be 12.8. The pH value was adjusted down 6 times to adjust the final pH value to 8.0 at the end. The pH value was adjusted down to 0.8 each time. After each adjustment to the adjusted value, the pH value of the adjusted reaction slurry was kept constant for 12 minutes. After the second gelation reaction was completed, aging began. The aging temperature was 75°C, the pH value was controlled at 7.8, and the aging time was 2.9 hours to obtain the second slurry. The aged slurry was filtered, and the filter cake was dried for the first time, dried at 120°C for 8 hours, rolled, and extruded into a clover shape. The formed strips were cured at 68°C for 43 hours, then the temperature was lowered to 18°C ​​and cured for 35 hours. The strips were washed with deionized water at room temperature until neutral. The wet strips were then dried at 90°C for 9.0 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.

[0054] Example 3

[0055] Nickel chloride is added to a dissolution tank 1 filled with deionized water to prepare a Ni-containing solution, wherein the weight concentration of Ni in the Ni-containing solution as NiO is 20 g / L. Nickel chloride and aluminum chloride solutions are respectively added to a dissolution tank 2 filled with deionized water to prepare Ni- and Al-containing solutions, wherein the weight concentration of Ni in the Ni- and Al-containing solution as NiO is 24 g / L, and the weight concentration of Al as Al2O3 is 32 g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni- and Al-containing solution used is 10:12. The Ni-containing solution is put into the reaction tank 1, and the sodium hydroxide solution (weight concentration is 12%) and the sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 34g / L) are dripped into the reaction tank 1 to carry out the first gelation reaction. When the remaining volume of the Ni-containing solution is 1 / 4, the gelation is stopped and allowed to stand for 23 minutes, and then the remaining Ni-containing solution, sodium molybdate solution, water glass (weight concentration of SiO2 is 26g / L), and sodium hydroxide solution (weight concentration is 14%) are continued to be gelled until the reaction is completed. The gelation temperature is maintained at 53°C, the pH value is controlled at 8.0 at the end of the reaction, and the gelation time is controlled at 1.2 hours. After the reaction is completed, aging is carried out, the aging temperature is 80°C, the aging pH value is controlled at 8.2, and the aging is carried out for 1.7 hours to obtain the first slurry. First, 1000mL of deionized water and 80mL of peanut oil were added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 18g / L as P2O5), the first slurry, the solution containing Ni and Al and the sodium tungstate solution (the weight concentration of W as WO3 was 48 / L) were added to the reaction tank 2 in parallel for the second gelation reaction. The gelation temperature was maintained at 72°C, and the pH value was initially controlled to be 12.9. The pH value was adjusted down 5 times to adjust the final pH value to 7.9 at the end. The pH value was adjusted down to 1.0 each time. After each adjustment to the adjusted value, the adjusted pH value of the reaction slurry was kept constant for 16 minutes. After the second gelation reaction was completed, aging began. The aging temperature was 82°C and the aging pH value was controlled at 8.4. After aging for 3.3 hours, the precipitate slurry continued to be aged under high pressure. The pressure was 13.5MPa, the aging temperature was 170°C, the aging time was 1.2 hours, and the aging pH value was 11.7 to obtain the second slurry. The aged slurry was filtered, the filter cake was dried at 70°C for 12 hours, rolled, and extruded into a clover-shaped strip. The formed strip was cured at 65°C for 68 hours. It was washed with deionized water at room temperature until neutral. The wet strip was then dried at 110°C for 9.0 hours, and the dried material was calcined at 530°C for 6 hours to obtain catalyst C. The catalyst composition and main properties are shown in Table 1.

[0056] Example 4

[0057] Nickel chloride is added to a dissolution tank 1 filled with deionized water to prepare a Ni-containing solution, wherein the weight concentration of Ni in the Ni-containing solution as NiO is 36 g / L. Nickel chloride and aluminum chloride solutions are respectively added to a dissolution tank 2 filled with deionized water to prepare Ni- and Al-containing solutions, wherein the weight concentration of Ni in the Ni- and Al-containing solution as NiO is 20 g / L, and the weight concentration of Al as Al2O3 is 32 g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni- and Al-containing solution used is 18:10. The Ni-containing solution is put into the reaction tank 1, and the sodium hydroxide solution (weight concentration is 15%) and the sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 28g / L) are dripped into the reaction tank 1 to carry out the first gelation reaction. When the remaining volume of the Ni-containing solution is 1 / 3, the gelation is stopped and allowed to stand for 18 minutes, and then the remaining Ni-containing solution, sodium molybdate solution, dilute water glass solution (weight concentration of SiO2 is 20g / L), and sodium hydroxide solution (weight concentration is 10%) are continued to be gelled until the reaction is completed. The gelation temperature is maintained at 65°C, the pH value is controlled at 8.3 at the end of the reaction, and the gelation time is controlled at 1.4 hours. After the reaction is completed, aging is carried out, the aging temperature is 85°C, the aging pH value is controlled at 8.3, and the aging is carried out for 1.5 hours to obtain the first slurry. First, 800 mL of deionized water and 70 mL of sunflower oil were added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 20 g / L in terms of P2O5), the first slurry, the solution containing Ni and Al, and the sodium tungstate solution (the weight concentration of W in terms of WO3 was 44 g / L) were added to the reaction tank 2 for the second gelation reaction. The gelation temperature was maintained at 50°C, and the pH value was initially controlled to be 12.5. The pH value was adjusted downward by 6, and the final pH value at the end was adjusted to 7.1. The pH value was adjusted downward by 0.9 each time. After each adjustment to the adjusted value, the adjusted pH value of the reaction slurry was kept constant for 13 minutes. After the second gelation reaction was completed, aging began, the aging temperature was 77°C, the aging pH value was controlled at 8.2, and the aging was performed for 2.8 hours. Then, the precipitate slurry was further aged under high pressure, the pressure was 13.2 MPa, the aging temperature was 165°C, the aging time was 1.8 hours, and the aging pH value was 11.4. The second slurry was obtained. The aged slurry was filtered, the filter cake was dried at 90°C for 12 hours, rolled, and extruded into a clover-shaped strip. The formed strip was cured at 70°C for 47 hours, then the temperature was reduced to 23°C and continued to cure for 32 hours. It was washed with deionized water at room temperature until neutral. The wet strip was then dried at 120°C for 8.0 hours, and the dried material was calcined at 520°C for 5 hours to obtain catalyst D. The catalyst composition and main properties are shown in Table 1.

[0058] Comparative Example 1

[0059] The reference agent E having the same catalyst composition as that of Example 1 was prepared, and the specific process was as follows:

[0060] According to the catalyst composition of Example 1, nickel chloride, aluminum chloride and water glass are dissolved in deionized water to prepare a mixed solution, wherein the weight concentration of Ni in terms of NiO is 52g / L, the weight concentration of Al in terms of Al2O3 is 36g / L, and the weight concentration of SiO2 is 36g / L. 500mL of deionized water is added to a reaction tank, and a 10wt% NaOH solution, a sodium molybdate solution (the weight concentration of Mo in terms of MoO3 is 36g / L), a sodium tungstate solution (the weight concentration of W in terms of WO3 is 40g / L) and a mixed solution are added to the reaction tank in parallel to form a gel, and the gelling temperature is maintained at 62°C, the pH value is controlled at 7.8 at the end, and the gelling time is controlled at 1.2 hours to generate a nickel- and tungsten-containing precipitate slurry. Then, aging is performed, the aging time is 2.0 hours, the aging temperature is 78°C, the pH value is controlled at 7.5 during aging, and the reaction slurry is filtered after the aging is completed, and the filter cake is dried at 100°C for 7 hours, rolled, and extruded into strips. The molded product was washed with deionized water at room temperature, but no molded product was obtained after washing. The powder was dried at 100°C for 12 hours and calcined at 500°C for 4 hours to obtain catalyst E. The composition and main properties of the catalyst are shown in Table 1.

[0061] Comparative Example 2

[0062] According to the method disclosed in CN102049295A, a reference agent F having a catalyst composition similar to that of Example 1 was prepared. The specific process is as follows:

[0063] After adding 1000mL of deionized water into the dissolving tank, nickel chloride, ammonium metatungstate and aluminum chloride solution are added in sequence, and mixed solution is prepared after uniform stirring. Among them, the weight concentration of Ni in terms of NiO is 52g / L, the weight concentration of W in terms of WO3 is 40g / L, and the weight concentration of Al in terms of Al2O3 is 54g / L. Take 160g of ammonium bicarbonate to prepare an aqueous solution with a molar concentration of 2.5mol / L. Then the mixed solution, ammonium bicarbonate aqueous solution and precipitant 10% ammonia water are added to the reaction tank filled with deionized water at the same time and flow to form gel. The gel pH value is 7.8 and the gel temperature is 62°C. After the gel is completed, add the slurry containing SAPO-11 molecular sieve and age for 2 hours at an aging temperature of 78°C. The pH value is controlled at 7.5 during aging. After aging, the filter cake was filtered, 600 mL of deionized water and 36 g of molybdenum trioxide were added, slurried and stirred evenly, and filtered. The filter cake was dried at 100°C for 7 hours, then extruded into strips, washed with deionized water until neutral, and the wet strips were dried at 100°C for 12 hours and calcined at 500°C for 4 hours to obtain the final catalyst F. The composition and main properties are shown in Table 1.

[0064] The SAPO-11 molecular sieve used in the comparative example is the one used in CN102049295A, which can be synthesized by conventional methods, such as hydrothermal crystallization method, and has the following properties: SiO2 / Al2O3 molar ratio of 0.85, infrared acid content of 0.9 mmol / g, pore volume of 0.24 mL / g, specific surface area of ​​250 m 2 / g, particle size is 450nm and crystallinity is 85%.

[0065] Comparative Example 3

[0066] Reference agent G was prepared according to the preparation method of Example 1 (no grease was added to the gelling tank during the second step of gelling) and the catalyst composition.

[0067] Add nickel chloride to dissolution tank 1 filled with deionized water to prepare a solution containing Ni, and the weight concentration of Ni in the Ni solution as NiO is 28g / L. Add nickel chloride and aluminum chloride solutions to dissolution tank 2 filled with deionized water to prepare solutions containing Ni and Al, and the weight concentration of Ni in the Ni and Al solution as NiO is 24g / L, and the weight concentration of Al as Al2O3 is 26g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni-containing solution used is 14:12. A Ni-containing solution, a sodium hydroxide solution (weight concentration of 12%) and a sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 36 g / L) are dropped into reaction tank 1 for a first gelling reaction. When the remaining volume of the Ni-containing solution is 1 / 3, the gelling is stopped and allowed to stand for 15 minutes. Then, the remaining Ni-containing solution, sodium molybdate solution, dilute water glass solution (weight concentration of SiO2 is 26 g / L) and sodium hydroxide solution (weight concentration is 12%) are continued to be gelled until the reaction is completed. The gelling temperature is maintained at 62°C. At the end of the reaction, the pH value is controlled at 7.8 and the gelling time is controlled at 1.2 hours. After the reaction is completed, aging is carried out at a temperature of 78°C and a pH value of 7.5. The aging is carried out for 1.8 hours to obtain a first slurry. First, 800 mL of deionized water was added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 20 g / L in terms of P2O5), the first slurry, the solution containing Ni and Al, and the sodium tungstate solution (the weight concentration of W in terms of WO3 was 40 g / L) were added to the reaction tank 2 for the second gelation reaction. The gelation temperature was maintained at 60°C, and the pH value was initially controlled to be 13.0. The pH value was adjusted down 6 times to adjust the final pH value to 7.6 at the end. The pH value was adjusted down to 0.9 each time. After each adjustment to the adjusted value, the adjusted pH value of the reaction slurry was kept constant for 10 minutes. After the second gelation reaction was completed, aging began. The aging temperature was 78°C, the pH value was controlled at 8.0, and the aging time was 2.5 hours to obtain the second slurry. The aged slurry was filtered, and the filter cake was dried at 100°C for 7 hours, rolled, and extruded into a clover shape. The formed strips were cured at 70°C for 50 hours, then the temperature was lowered to 20°C and the curing continued for 30 hours. The strips were washed with deionized water at room temperature until neutral. The wet strips were then dried at 100°C for 12.0 hours, and the dried material was calcined at 500°C for 4 hours to obtain Catalyst G. The composition and main properties of the catalyst are shown in Table 1.

[0068] Comparative Example 4

[0069] Reference agent H was prepared according to the preparation method of Example 1 (no silicon was added when preparing mixed solution A).

[0070] Add nickel chloride and aluminum chloride solutions to a dissolution tank 1 filled with deionized water to prepare a solution A containing Ni and Al, wherein the weight concentration of Ni in solution A containing Ni and Al is 28 g / L as NiO, and the weight concentration of Al in solution A containing Ni and Al is 26 g / L as Al2O3. Add nickel chloride and aluminum chloride solutions to a dissolution tank 2 filled with deionized water to prepare a solution B containing Ni and Al, wherein the weight concentration of Ni in solution B containing Ni and Al is 24 g / L as NiO, and the weight concentration of Al in solution B containing Ni and Al is 26 g / L as Al2O3. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni-containing solution used is 14:12. Solution A containing Ni and Al, sodium hydroxide solution (weight concentration of 12%) and sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 36 g / L) are dropped into reaction tank 1 for the first gelling reaction. The gelling temperature is maintained at 62°C. At the end of the reaction, the pH value is controlled at 7.8 and the gelling time is controlled at 1.2 hours. After the reaction, aging is carried out at 78°C and the aging pH value is controlled at 7.5 for 1.8 hours to obtain the first slurry. First, 800 mL of deionized water and 60 mL of rapeseed oil were added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 20 g / L in terms of P2O5), the first slurry, the solution B containing Ni and Al, and the sodium tungstate solution (the weight concentration of W in terms of WO3 was 40 g / L) were added to the reaction tank 2 for the second gelation reaction. The gelation temperature was maintained at 60 ° C, and the pH value was initially controlled to be 13.0. The pH value was adjusted down 6 times to adjust the final pH value to 7.6 at the end. The pH value was adjusted down to 0.9 each time. After each adjustment to the adjusted value, the adjusted pH value of the reaction slurry was kept constant for 10 minutes. After the second gelation reaction was completed, aging began. The aging temperature was 78 ° C, the pH value was controlled at 8.0, and the aging time was 2.5 hours to obtain the second slurry. The aged slurry was filtered, the filter cake was dried at 100 ° C for 7 hours, rolled, and extruded into a clover shape. The formed strips were cured at 70°C for 50 hours, then the temperature was lowered to 20°C and cured for another 30 hours. The strips were washed with deionized water at room temperature until neutral. The wet strips were then dried at 100°C for 12.0 hours, and the dried material was calcined at 500°C for 4 hours to obtain Catalyst H. The composition and main properties of the catalyst are shown in Table 1.

[0071] Comparative Example 5

[0072] According to the method of Example 1, Catalyst I was prepared according to the component content ratio of Catalyst A in Table 1, and the formed strips were not subjected to desalination treatment.

[0073] Add nickel chloride to dissolution tank 1 filled with deionized water to prepare a solution containing Ni, and the weight concentration of Ni in the Ni solution as NiO is 28g / L. Add nickel chloride and aluminum chloride solutions to dissolution tank 2 filled with deionized water to prepare solutions containing Ni and Al, and the weight concentration of Ni in the Ni and Al solution as NiO is 24g / L, and the weight concentration of Al as Al2O3 is 26g / L. Among them, the mass ratio of Ni in the Ni-containing solution used in the reaction of this embodiment to Ni in the Ni-containing solution used is 14:12. A Ni-containing solution, a sodium hydroxide solution (weight concentration of 12%) and a sodium molybdate solution (weight concentration of Mo calculated as MoO3 is 36 g / L) are dropped into reaction tank 1 for a first gelling reaction. When the remaining volume of the Ni-containing solution is 1 / 3, the gelling is stopped and allowed to stand for 15 minutes. Then, the remaining Ni-containing solution, sodium molybdate solution, dilute water glass solution (weight concentration of SiO2 is 26 g / L), and sodium hydroxide solution (weight concentration is 12%) are continued to be gelled until the reaction is completed. The gelling temperature is maintained at 62°C. At the end of the reaction, the pH value is controlled at 7.8 and the gelling time is controlled at 1.2 hours. After the reaction is completed, aging is carried out at a temperature of 78°C and a pH value of 7.5. The aging is carried out for 1.8 hours to obtain a first slurry. First, 800 mL of deionized water and 60 mL of rapeseed oil were added to the reaction tank 2, and then the sodium phosphate alkaline solution (the weight concentration of P in the sodium phosphate solution was 20 g / L in terms of P2O5), the first slurry, the solution containing Ni and Al, and the sodium tungstate solution (the weight concentration of W in terms of WO3 was 40 g / L) were added to the reaction tank 2 for the second gelation reaction. The gelation temperature was maintained at 60 ° C, and the pH value was initially controlled to be 13.0. The pH value was adjusted down 6 times to adjust the final pH value to 7.6 at the end. The pH value was adjusted down to 0.9 each time. After each adjustment to the adjusted value, the pH value of the adjusted reaction slurry was kept constant for 10 minutes. After the second gelation reaction was completed, aging began. The aging temperature was 78 ° C, the pH value was controlled at 8.0, and the aging time was 2.5 hours to obtain the second slurry. The aged slurry was filtered, the filter cake was dried at 100 ° C for 7 hours, rolled, and extruded into a clover shape. It was washed with deionized water at room temperature, and no molded product was obtained after washing. The powder was calcined at 500°C for 4 hours to obtain Catalyst I. The composition and main properties of the catalyst are shown in Table 1.

[0074] Comparative Example 6

[0075] According to the preparation method disclosed in CN106513006A, a reference agent J having a catalyst composition similar to that of Example 1 of the present invention was prepared. The specific process is as follows:

[0076] Nickel carbonate and 300 ml of deionized water were uniformly mixed and added to a 1L high-pressure ultrasonic reactor. The ultrasonic frequency was set to 60 KHz, and the mixture was heated to 80°C. After being kept at this temperature for 1 hour, the ultrasonic frequency was reduced to 20 KHz, the system temperature was increased to 120°C, ammonium molybdate and 3 g of polyvinyl pyrrolidone were added, and then 10 ml of 25 wt% ammonia water was added dropwise to the system. After being kept at this temperature for 2 hours, the ultrasound was turned off, stirring was turned on, and the speed was 300 rpm. Ammonium metatungstate was added, and then citric acid was added until the pH of the system was 4.2. After being kept at this temperature for 2 hours, the heating was turned off, and the slurry was collected after the system was cooled to room temperature. The slurry was spray dried, and the inlet temperature and outlet temperature were controlled at about 200°C and 100°C, respectively. The obtained dry powder was roasted at 330°C in a muffle furnace for 3 hours to obtain the active component powder. The active component powder was mixed with aluminum hydroxide dry gel, and then a 10% dilute nitric acid aqueous solution was added for kneading and extrusion to obtain a strip. The strip was dried at 110°C for 10 hours and calcined in a muffle furnace at 400°C for 5 hours to obtain a reference agent J. The catalyst composition and main properties are shown in Table 1.

[0077] Comparative Example 7

[0078] According to the preparation method disclosed in CN1951558A, reference agent K was prepared as follows:

[0079] Add deionized water to the dissolving tank, add nickel chloride, ammonium metatungstate and aluminum chloride to dissolve, prepare acidic working solution A, the weight concentration of Ni in solution A is 74.8g / L in terms of NiO, the weight concentration of W in terms of WO3 is 48.6g / L, the weight concentration of Al in terms of Al2O3 is 44g / L, and the pH value of solution A is 1.8. Add 350mL of deionized water to the reaction tank, and the temperature rises to 62°C. Under stirring, add solution A and 10wt% ammonia water to the reaction tank in parallel to form gel, the gelling temperature is 62°C, the gelling time is 1 hour, and the pH value of the slurry during the gelling process is 8.5. After the gelling is completed, age for 2 hours, the aging temperature is 75°C, and the pH value is controlled at 7.6 during aging. Then filter, add 600mL of deionized water and 32.6g of molybdenum trioxide to the filter cake, beat and stir evenly, filter, dry the filter cake at 120°C for 8 hours, roll, and extrude into a cylindrical shape. The wet strips were washed with deionized water at room temperature until neutral. The wet strips were then dried at 80°C for 10 hours and calcined at 500°C for 4 hours to obtain catalyst K. The catalyst composition and main properties are shown in Table 1.

[0080] Example 5

[0081] This example is an activity evaluation experiment of the catalyst of the present invention, and is compared with the catalyst of the comparative example. From the physicochemical properties of the catalyst in Table 1, it can be seen that when the raw materials contain more sodium raw materials during the preparation process, the catalysts A, B, C of the present invention and the comparative catalysts F, G, H, J, K are used for washing (the comparative catalysts E and F are washed into powders without activity evaluation), and a comparative evaluation test is carried out on a 200mL small hydrogenation device. The mixed diesel (the weight ratio of straight-run diesel, coking diesel, and catalytic diesel is 28:20:52) is the test raw material. The process conditions for the catalyst activity evaluation are: hydrogen partial pressure of 6.4MPa, reaction temperature of 365°C, liquid hourly volume space velocity of 2.0h -1 , the volume ratio of hydrogen to oil is 500:1, and the main properties of the raw materials are shown in Table 4. The results of catalyst activity evaluation are shown in Table 5. The types of sulfides in the hydrorefined oil were detected by gas chromatography-atomic emission spectrometry detector (GC-AED), and the results are shown in Table 6.

[0082] It can be seen from Table 1 that when the catalyst of the present invention uses a relatively high sodium-containing raw material in the preparation process, the catalyst has good crushing strength after desalting and washing after molding, while without desalting, the molded catalyst strips become powder after washing.

[0083] It can be seen from the evaluation results that compared with the comparative example catalyst, the catalyst of the present invention shows high hydrodesulfurization activity when removing difficult-to-treat 4,6-DMDBT macromolecular sulfides, and has excellent ultra-deep hydrodesulfurization activity. At the same time, the diesel product has a good yield. When the activity evaluation reaction space velocity is increased, the catalyst of the present invention still has excellent ultra-deep desulfurization activity by increasing the reaction temperature. Compared with the evaluation results of the comparative example catalyst, the catalyst of the present invention effectively reduces the influence of thermodynamic equilibrium on the high-temperature hydrogenation pathway and has good temperature adaptability. The hydrorefining catalyst of the present invention has a large pore volume and specific surface area, and the pore distribution is mainly concentrated above 10nm. The catalyst of the present invention is used for processing light distillate oil, especially for processing inferior diesel fractions, and has excellent ultra-deep hydrodesulfurization and denitrification performance.

[0084] Table 1 Composition and properties of catalysts prepared in Examples and Comparative Examples

[0085] Catalyst No. A B C D NiO, wt% 26 34 22 28 <![CDATA[WO3,wt%]]> 20 12 24 22 <![CDATA[MoO3,wt%]]> 18 20 17 14 <![CDATA[SiO2,wt%]]> 13 14 12 10 <![CDATA[Al2O3,wt%]]> 13 12 16 16 <![CDATA[P2O5,wt%]]> 10 8 9 10 <![CDATA[Na2O,%]]> 0.076 0.078 0.084 0.068 <![CDATA[Specific surface area, m 2 / g]]> 301 316 305 299 Pore ​​volume, mL / g 0.415 0.433 0.420 0.411 Pore ​​distribution <4nm 4.34 4.06 4.25 4.42 4nm~10nm 22.83 22.03 22.25 23.13 10nm~15nm 41.94 42.78 42.56 41.63 >15nm 30.89 31.13 30.94 30.82 Mechanical strength, N / mm 19.6 19.5 19.6 19.8

[0086] Table 1 (Continued) Composition and properties of catalysts prepared in Examples and Comparative Examples

[0087] Catalyst No. E F G H I J K NiO, wt% 26 26 26 26 26 26 37.4 <![CDATA[WO3,wt%]]> 20 20 20 20 20 20 24.3 <![CDATA[MoO3,wt%]]> 18 18 18 18 18 18 16.3 <![CDATA[SiO2,wt%]]> 18 4 13 - 13 - - <![CDATA[Al2O3,wt%]]> 18 28 13 26 13 36 22 <![CDATA[P2O5,wt%]]> - 4 10 10 10 - - <![CDATA[Na2O,%]]> 0.42 0.14 0.094 0.079 0.551 0.13 0.13 <![CDATA[Specific surface area, m 2 / g]]> 142 199 259 299 245 283 174 Pore ​​volume, mL / g 0.232 0.252 0.363 0.412 0.357 0.385 0.301 Pore ​​distribution <4nm 62.81 22.82 11.85 4.68 15.43 38.21 46.87 4nm~10nm 30.52 71.44 34.13 22.92 40.64 48.61 40.72 10nm~15nm 4.37 4.50 35.44 41.87 29.72 7.28 8.26 >15nm 2.30 1.24 18.58 30.53 14.21 5.90 4.15 Mechanical strength, N / mm - 17.6 18.8 19.7 - 13.5 19.1

[0088] Table 2 Composition of composite oxides in the core and shell of the catalysts obtained in each example

[0089] Catalyst No. A B C D G H I Based on the catalyst mass, the composite oxide composition in the core NiO, wt% 14 24 10 18 17 14 14 <![CDATA[MoO3,wt%]]> 18 20 17 14 13 18 18 <![CDATA[SiO2,wt%]]> 13 14 12 10 8 - 13 <![CDATA[WO3,wt%]]> - - - - 8 - - <![CDATA[Al2O3,wt%]]> - - - - 4 13 - <![CDATA[P2O5,wt%]]> - - - - 4 Based on the catalyst mass, the composite oxide composition in the shell NiO, wt% 12 10 12 10 9 12 12 <![CDATA[WO3,wt%]]> 20 12 24 22 12 20 20 <![CDATA[Al2O3,wt%]]> 13 12 16 16 9 13 13 <![CDATA[MoO3,wt%]]> - - - - 5 - - <![CDATA[SiO2,wt%]]> - - - - 5 - - <![CDATA[P2O5,wt%]]> 10 8 9 10 6 10 10

[0090] Table 3 Average particle size and particle size distribution of the catalyst core-shell composite oxide particles obtained in each example

[0091] Catalyst No. A B C D E F Average particle size of core-shell composite oxide particles, nm 9.5 9.8 9.7 10.0 33.6 23.8 Particle size distribution of core-shell composite oxide particles, % Particle size less than 7nm 5.35 5.11 5.24 5.04 3.32 4.05 Particle size is 7nm-13nm 84.44 83.56 83.75 83.39 21.22 28.19 Particle size greater than 13nm 10.21 11.33 11.01 11.57 77.46 67.76

[0092] Table 3 (Continued) Average particle size and particle size distribution of the catalyst core-shell composite oxide particles obtained in each example

[0093] Catalyst No. G H I J K Average particle size of core-shell composite oxide particles, nm 31.5 9.6 12.0 24.4 19.4 Particle size distribution of core-shell composite oxide particles, % Particle size less than 7nm 3.76 5.27 6.09 8.93 8.42 Particle size is 7nm-13nm 28.13 84.55 77.42 28.46 33.62 Particle size greater than 13nm 68.11 10.18 16.49 62.61 57.96

[0094] Table 4 Main properties of crude oil

[0095] project Analyze the results <![CDATA[Density (20 °C), g / cm 3 > 0.8897 Distillation range, ℃ 175-379 S, µg / g 13100 N, µg / g 922

[0096] Table 5 Catalyst activity evaluation results

[0097] Catalyst No. A B C F G H J K <![CDATA[Generated oil density (20 °C), g / cm 3 > 0.8635 0.8633 0.8638 0.8656 0.8718 0.8664 0.8732 0.8707 S, µg / g 7.4 7.2 7.7 38.2 136.9 38.5 236.8 118.8 N, µg / g 3.1 3.0 3.3 16.4 66.2 14.4 112.8 62. 2 Diesel yield, % 99.2 99.1 99.2 86.6 98.7 99.1 98.3 98.9

[0098] Table 6 Content of different sulfides in hydrorefined oil

[0099] Catalyst No. A B C F G H J K Sulfur content in hydrorefined oil, µg / g 7.4 7.2 7.7 38.2 136.9 38.5 236.8 118.8 <![CDATA[C1-DBT,µg / g]]> 0 0 0 3.2 9.3 3.9 22.1 9.1 4- MDBT, µg / g 1.6 1.6 1.6 8.1 28.2 10.1 52.2 25.4 6-MDBT, µg / g 2.3 2.2 2.4 9.6 31.3 8.2 60.2 26.3 4,6-DMDBT, µg / g 3.5 3.4 3.7 17.3 68.1 16.3 102.3 58.0

Claims

1. A method for preparing a hydrotreating catalyst, characterized in that The method comprises the following steps: (1) reacting a Ni-containing solution, a sodium molybdate solution and a sodium hydroxide solution in parallel, stopping the reaction for 5 to 40 minutes when the volume of the Ni-containing solution is 1 / 5 to 1 / 2, then adding a silicon-containing alkaline solution to continue the gelling reaction, and subjecting the reaction to a first aging to obtain a first slurry containing Ni, Si and Mo; (2) adding water and an oily liquid into a reactor, and then adding a Ni- and Al-containing solution, a sodium tungstate solution, a sodium phosphate solution and the first slurry in parallel into the reactor to carry out a gelling reaction, and subjecting the reaction to a second aging to obtain a first slurry containing Ni, Si and Mo. The second slurry is then aged, and after the aging is completed, the solid-liquid separation is performed, and the solid phase is dried and formed to obtain a molded product; (4) the molded product is desalted, washed, dried and calcined to obtain a core-shell structured hydrogenation refining catalyst; the oily liquid in step (2) is an unsaturated higher fatty acid glyceride; the pH value is adjusted from the initial value to the final pH value by a stepwise reduction method, and the stepwise reduction method is to reduce the pH value to the desired value at that time, and keep the pH value of the reaction slurry constant until the next reduction begins, and the number of reductions is 2 to 10 times.

2. The method according to claim 1, characterized in that: The weight concentration of the sodium hydroxide solution in step (1) is 5% to 30%.

3. The method according to claim 1, characterized in that: The silicon-containing alkaline solution in step (1) is one or more of water glass and silica sol; the weight concentration of Si in the silicon-containing alkaline solution calculated as SiO2 is 5-90 g / L.

4. The method according to claim 1, characterized in that: In the sodium molybdate solution in step (1), the weight concentration of Mo in terms of MoO3 is 5-110 g / L.

5. The method according to claim 1, characterized in that: In the Ni-containing solution described in step (1), the weight concentration of Ni in terms of NiO is 5 to 120 g / L.

6. The method according to claim 1, characterized in that: The conditions of the gelling reaction in step (1) are: reaction temperature of 30-90° C., pH value of 7.0-11.0, and gelling time of 0.2-2.5 hours.

7. The method according to claim 1, characterized in that: The first aging conditions in step (1) are as follows: the aging temperature is 60-90° C., the pH value during aging is 7.0-11.0, and the aging time is 0.3-2.5 hours.

8. The method according to claim 1, characterized in that: In step (1), the weight of the introduced Ni accounts for 30% to 80% of the total Ni weight in the hydrotreating catalyst obtained in step (4), and the remaining Ni in the catalyst is introduced in step (2).

9. The method according to claim 1, characterized in that: In the solution containing Ni and Al in step (2), the weight concentration of Ni as NiO is 5-110 g / L, and the weight concentration of Al as Al2O3 is 2-95 g / L; in the sodium tungstate solution in step (2), the weight concentration of W as WO3 is 4-140 g / L.

10. The method according to claim 1, characterized in that: The weight concentration of P in the sodium phosphate solution described in step (2) is 2-70 g / L.

11. The method according to claim 1, characterized in that: The volume ratio of water added in step (2) to the volume ratio of the first slurry is 0.1:1 to 3:

1.

12. The method according to claim 1, characterized in that: The unsaturated higher fatty acid glyceride in step (2) is one or more of peanut oil, rapeseed oil, cottonseed oil, sunflower seed oil, soybean oil, corn oil, tea oil, and olive oil; the volume ratio of the unsaturated higher fatty acid glyceride to water is 1:60 to 1:

4.

13. The method according to claim 1, characterized in that: The conditions of the gelling reaction in step (2) are as follows: the reaction temperature is 30-90° C., the initial pH value is controlled at 10.0-14.0, the final pH value is 7.0-8.5 at the end, and the gelling reaction time is 0.5-6.0 hours.

14. The method according to claim 1, characterized in that: The second aging conditions described in step (2) are as follows: aging temperature is 40 to 90° C., aging time is 1 to 5 hours, and pH value is 7.0 to 11.

0.

15. The method according to claim 1, characterized in that The second aging condition in step (2) is carried out as follows: the first step is normal pressure aging: the aging temperature is 30-90°C, the aging time is 1-6 hours, and the pH value is 6.5-10.0; the second step is high pressure aging: the temperature is 100-195°C, the time is 0.1-3.5 hours, the pressure is 10-15 MPa, and the pH value is 10.0-13.

0.

16. The method according to claim 1, characterized in that: The desalination process described in step (4) is: first curing, then washing to remove the salt precipitated on the surface of the molded product, the curing conditions are a temperature of 5 to 100° C. and a time of 10 to 100 hours.

17. The method according to claim 1, characterized in that: The desalination treatment in step (4) is carried out as follows: the first stage is carried out at a temperature of 60 to 90°C for curing for 5 to 60 hours; the second stage is carried out at a temperature of 10 to 30°C for 1 to 48 hours, and then the precipitated salt is removed by washing.

18. A hydrotreating catalyst prepared according to any one of claims 1 to 17, characterized in that: The catalyst is a bulk hydrogenation catalyst with a core-shell structure, comprising composite amorphous oxide particles, wherein the core phase is an amorphous composite oxide containing molybdenum, nickel and silicon, and the shell phase is an amorphous composite oxide containing tungsten, nickel, phosphorus and aluminum; the catalyst is in the form of flakes, spheres, cylindrical bars and irregular bars; the average particle size of the catalyst particles is 8~13nm; the particle size distribution of the catalyst particles is as follows: the number of particles with a particle size less than 7nm accounts for 2%~15% of the total number of particles, the number of particles with a particle size of 7nm~13nm accounts for 66%~88% of the total number of particles, and the number of particles with a particle size greater than 13nm accounts for 3%~21% of the total number of particles.

19. The catalyst according to claim 18, characterized in that: Based on the mass of the composite amorphous oxide particles with a core-shell structure, the core phase accounts for 20% to 90%, and the shell phase accounts for 10% to 80%; the atomic molar ratio of molybdenum to nickel in the core phase is 1:28 to 12:1, and the content of silicon is 2% to 38% of the mass of the hydrorefining catalyst calculated as SiO2; the atomic molar ratio of tungsten to nickel in the shell phase is 1:22 to 8:1, the content of aluminum is 2% to 25% of the mass of the hydrorefining catalyst calculated as Al2O3, and the content of phosphorus is 3% to 20% of the mass of the hydrorefining catalyst calculated as P2O5; the Na2O content is less than 0.12%.

20. The catalyst according to claim 18, characterized in that: The properties of the hydrotreating catalyst are as follows: Specific surface area is 180~700m 2 / g, the pore volume is 0.30~0.90mL / g; the pore size distribution is as follows: the pore volume occupied by pores with a diameter of less than 4nm accounts for 1%~10% of the total pore volume, the pore volume occupied by pores with a diameter of 4~10nm accounts for 12%~40% of the total pore volume, the pore volume occupied by pores with a diameter of 10~15nm accounts for 22%~56% of the total pore volume, and the pore volume occupied by pores with a diameter of more than 15nm accounts for 18%~45% of the total pore volume.

21. Use of the hydrotreating catalyst prepared according to any one of claims 1 to 17 in diesel hydrotreating reaction.

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