Hydrogenation catalyst preparation and ex-situ presulfiding and catalytic cracking gasoline start-up process

Abstract

The application discloses a hydrogenation catalyst preparation and ex-vessel presulfurization and catalytic cracking gasoline starting method. The hydrogenation catalyst preparation method comprises the following steps: adding a carrier into an impregnation kettle, performing atomization and spraying treatment on the carrier by using a pre-spraying solution, and performing aging treatment after the spraying is completed; and dipping an active component on the carrier, aging, drying and roasting. The catalyst prepared by using the method has reasonable gradient distribution of the active component and excellent hydrogenation refining performance.

Description

Technical Field

[0001] This invention relates to a method for preparing a hydrogenation catalyst and for pre-sulfurizing and starting up gasoline via catalytic cracking. Background Technology

[0002] Aromatics, as a basic chemical raw material, hold an important position. Their production technology and level are one of the indicators of a country's petrochemical development level. Global demand for aromatics is constantly increasing, while my country's aromatics production cannot meet this demand. Currently, the main source of aromatics is the extraction and separation of cracked gasoline, a byproduct of catalytic reforming gasoline and ethylene plants. Therefore, broadening the sources of aromatics extraction feedstock is of great significance for improving my country's self-sufficiency in the aromatics market and reducing dependence on foreign markets.

[0003] Catalytic cracking is a technology developed based on catalytic cracking. Through process adjustments, catalytic cracking can produce gasoline with high aromatic content as a feedstock for aromatics production. However, aromatics products have very strict requirements for impurities such as sulfur and nitrogen. Therefore, before aromatics extraction, catalytic cracked gasoline needs to be saturated with olefins and impurities such as sulfur and nitrogen removed.

[0004] Catalytic cracking technology emerged relatively late, and patent literature on hydrogenation catalysts and hydrotreating processes for catalytic cracking gasoline is scarce. Hydrotreating technology centered on hydrogenation catalysts for cracked gasoline (a byproduct of steam cracking to ethylene production) is an important branch of the hydrotreating field and can provide a reference for catalytic cracking gasoline hydrotreating technology. However, there are still some differences between catalytic cracking gasoline and steam cracking gasoline, mainly in that catalytic cracking gasoline has higher nitrogen, sulfur, and diene content, and its components are relatively heavier. The feedstock used in steam thermal cracking processes is lighter (mostly naphtha), resulting in relatively low sulfur content and virtually no nitrogen in steam cracking gasoline; the feedstock used in catalytic cracking processes is heavier (wax oil or residue oil), leading to higher sulfur and nitrogen content in the catalytic cracking process. Therefore, the lower quality of catalytic cracking gasoline places higher demands on hydrorefining catalysts. The hydrorefining process for catalytic cracking gasoline aimed at producing aromatics extraction feedstock needs to solve two key problems: first, the catalyst must have low aromatics saturation activity under high desulfurization, denitrification, and olefin saturation activity; second, higher requirements are placed on the catalyst's anti-coking performance to ensure long-term stable operation of the unit.

[0005] Hydrorefining catalysts are classified into supported and unsupported types, with supported catalysts being more prevalent in industrial applications. Supported hydrorefining catalysts are generally prepared by impregnating an active metal (Mo, W, Ni, Co, etc.) onto a support. The active components of the catalyst prepared by the impregnation method are distributed on the inner and outer surfaces of the catalyst support, including the deep pores and the inner surfaces of the pores.

[0006] Conventional methods produce hydrorefining catalysts with active metals in an oxidized state, while the actual catalytically active component is in a sulfidated state. Therefore, the catalyst must undergo sulfidation activation before use, a process known as pre-sulfidation. Pre-sulfidation significantly impacts catalyst performance and is a crucial pretreatment step. Based on the sulfur loading method, pre-sulfidation methods can be categorized into in-vessel pre-sulfidation and external pre-sulfidation.

[0007] In-reactor pre-sulfurization technology involves loading the catalyst into the reactor before sulfidation. The hydrogen sulfide required for the reaction is usually produced by decomposing a sulfiding agent. Industrially, dimethyl disulfide (hereinafter referred to as DMDS) is commonly used. The main sulfidation steps are as follows: under hot hydrogen circulation (reactor inlet temperature reaches 180℃), DMDS is gradually injected into the system, then decomposes with hydrogen to release hydrogen sulfide gas, which then reacts with the oxidized catalyst in the reactor to finally obtain the sulfided catalyst. This method has three main problems: (1) the sulfiding agent used is toxic and harmful, and easily causes environmental pollution; (2) the equipment needs to be equipped with sulfidation facilities and supporting pipelines that are only used during operation; (3) the equipment poses safety and environmental hazards during the sulfidation process due to high temperature, high pressure, and high H2S concentration.

[0008] Therefore, the external pre-sulfurization method has emerged. The advantages of external pre-sulfurization technology are: (1) External pre-sulfurization technology improves the utilization rate of active metal components of hydrogenation catalyst and makes the catalyst more fully sulfided; (2) External pre-sulfurization technology can save start-up time and make the start-up process more convenient; (3) The start-up site of external pre-sulfurization catalyst avoids the use of toxic sulfides and does not require the installation of special sulfidation facilities. Summary of the Invention

[0009] The inventors discovered that in existing technologies, the impregnation step of the active component during the preparation of hydrogenation catalysts involves a concentrated release of adsorption heat, affecting the dispersion state of the active components and the physicochemical properties of the catalyst in the later stages. Based on this, the present invention provides a method for preparing hydrogenation catalysts and for external pre-sulfurization and catalytic cracking of gasoline start-up. This method pre-sprays the catalyst support, thereby releasing some of the adsorption heat generated during the catalyst preparation process. Simultaneously, the spray liquid interacts with the support to adjust its properties, resulting in a more rational gradient distribution of the active components in the catalyst. Furthermore, it reduces the amount of sulfiding agent required during external pre-sulfurization.

[0010] In a first aspect, the present invention provides a method for preparing a hydrogenation catalyst, comprising:

[0011] The carrier is added to the impregnation pot, and the carrier is sprayed with a pre-spraying solution. After spraying, the carrier is aged.

[0012] The active components are impregnated onto a carrier, aged, dried, and calcined.

[0013] In one or more alternative embodiments, the pre-spraying solution is an aqueous solution of citric acid or a potassium hydroxide solution.

[0014] In one or more optional embodiments, when the pre-spraying solution is an aqueous solution of citric acid, a salt containing the active component is added to an aqueous solution of inorganic acid to impregnate the carrier.

[0015] or,

[0016] When the pre-spraying solution is a potassium hydroxide solution, potassium hydroxide, ammonia and / or polyamine complexing agent, and deionized water are mixed to prepare a composite solvent, and a salt containing the active component is added to the composite solvent to impregnate the carrier.

[0017] In one or more optional embodiments, the active component is molybdenum, cobalt, or nickel.

[0018] In one or more optional embodiments, the salt of the active component is ammonium molybdate and / or molybdenum oxide, cobalt nitrate and / or cobalt acetate, nickel nitrate and / or nickel acetate.

[0019] In one or more optional embodiments, the spraying treatment time is 1 to 20 minutes, preferably 3 to 10 minutes; the aging treatment time is 5 to 30 minutes, preferably 10 to 20 minutes.

[0020] In one or more optional embodiments, the specific surface area of ​​the carrier is 120–260 m². 2 / g, preferably 150-220m 2 / g; the water absorption rate of the carrier is 70% to 120%, preferably 80% to 100%.

[0021] Secondly, the present invention provides a hydrogenation catalyst prepared by the above-described preparation method.

[0022] In one or more optional embodiments, the hydrogenation catalyst contains 10-20 wt% molybdenum oxide, preferably 13-18 wt%; 1.5-8 wt% nickel oxide, preferably 2-6 wt%; 0-5 wt% cobalt oxide, preferably 0.5-2.5 wt%; and the balance is a support.

[0023] Thirdly, the present invention provides an off-site presulfurization method for the above-mentioned hydrogenation catalyst, comprising:

[0024] The above-mentioned hydrogenation catalyst is placed in an impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst by spraying.

[0025] In one or more optional embodiments, the pre-sulfurized raw material is a mixture of a sulfiding agent and a sulfidation accelerator; the amount of the sulfiding agent is 20-70% of the theoretical sulfur requirement of the hydrogenation catalyst, preferably 25-50%; the amount of the sulfidation accelerator is 0.5-40% of the weight of the hydrogenation catalyst, preferably 3-25%.

[0026] Fourthly, the present invention provides a presulfurized hydrogenation catalyst prepared by the above-mentioned external presulfurization method.

[0027] In one or more optional embodiments, the mass ratio of sulfur to active metal element in the presulfurized hydrogenation catalyst is 0.2 to 0.7, preferably 0.25 to 0.5.

[0028] Fifthly, the present invention provides a method for starting up catalytic cracking gasoline, comprising:

[0029] The above-mentioned presulfurized hydrogenation catalyst is loaded into the reactor;

[0030] After passing the airtightness test, under hydrogen circulation conditions, the reactor inlet temperature is increased at a rate of 15-25℃ / hour. When the catalyst bed temperature reaches 150-160℃, it is kept at a constant temperature for 3-5 hours; when the catalyst bed temperature reaches 180-220℃, it is kept at a constant temperature for 2-10 hours; when the catalyst bed temperature reaches 260-320℃, it is kept at a constant temperature for 4-10 hours.

[0031] Adjust the reaction conditions to meet the requirements of the system process, and switch to the feedstock oil for normal operation.

[0032] Based on the above technical solution, the beneficial effects of the present invention compared with the prior art are as follows:

[0033] This invention employs a pre-spraying method to prepare a hydrogenation catalyst, pre-releasing some of the adsorption heat generated during catalyst preparation. This results in a more rational gradient distribution of the active components in the catalyst, leading to superior hydrorefining performance. Furthermore, due to the rational gradient distribution of active components, the hydrogenation catalyst prepared by this invention requires less sulfurizing agent for pre-sulfurization, significantly reducing hydrogen sulfide emissions during operation, lowering production costs and operational safety risks, and minimizing environmental pollution. Moreover, this invention's hydrogenation catalyst and its external pre-sulfurization method, while significantly reducing the amount of sulfurizing agent required for pre-sulfurization, can still meet the demand for aromatics production from high-sulfur, high-nitrogen catalytic cracking gasoline. Attached Figure Description

[0034] Figure 1 The image shows the SEM-EDS characterization results of the hydrogenation catalyst C1 provided in Example 1 of this invention.

[0035] Figure 2The image shows the SEM-EDS characterization results of the hydrogenation catalyst C5 provided in Example 5 of this invention. Detailed Implementation

[0036] The following provides a detailed description of the embodiments of the present invention: These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and processes. However, the scope of protection of the present invention is not limited to the following embodiments. Process parameters not specified in the following embodiments are generally performed under conventional conditions.

[0037] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0038] The following provides a detailed description of various specific embodiments of the hydrogenation catalyst preparation, external pre-sulfurization, and catalytic cracking gasoline start-up method provided in the embodiments of the present invention.

[0039] This invention provides a method for preparing a hydrogenation catalyst, comprising:

[0040] The carrier is added to the impregnation pot, and the carrier is sprayed with a pre-spraying solution. After spraying, the carrier is aged.

[0041] The active components are impregnated onto a carrier, aged, dried, and calcined.

[0042] In this embodiment of the invention, the spraying process uses conventional spraying equipment.

[0043] In this embodiment of the invention, the carrier is directly used for catalyst preparation without drying and calcination after spray aging.

[0044] In one or more alternative embodiments, the pre-spraying solution is an aqueous solution of citric acid or a potassium hydroxide solution.

[0045] In one or more optional embodiments, when the pre-spraying solution is an aqueous solution of citric acid, a salt containing the active component is added to an aqueous solution of inorganic acid to impregnate the carrier.

[0046] or,

[0047] When the pre-spraying solution is a potassium hydroxide solution, potassium hydroxide, ammonia and / or polyamine complexing agent, and deionized water are mixed to prepare a composite solvent, and a salt containing the active component is added to the composite solvent to impregnate the carrier.

[0048] In this embodiment of the invention, the pre-spraying solution is prepared by dissolving citric acid or potassium hydroxide in deionized water to prepare a pre-spraying solution of the required concentration.

[0049] In this embodiment of the invention, the volume percentage of the pre-spray solution added to the catalyst support during the atomization spraying process is 1% to 20% of the total impregnation liquid volume (including the volume of the pre-spray solution and the volume of the active component impregnation liquid), preferably 5% to 10%.

[0050] In one or more optional embodiments, the active component is molybdenum, cobalt, or nickel.

[0051] In one or more optional embodiments, the active component molybdenum is preferably added in the form of ammonium molybdate / molybdenum oxide; the active components cobalt and nickel can be added in the form of their sulfates, halides, nitrates or acetates. Since the nitrates and acetates of cobalt and nickel have good solubility, which is beneficial to the distribution of the active components on the support, the active components cobalt and nickel are preferably added in the form of cobalt nitrate and / or cobalt acetate, nickel nitrate and / or nickel acetate.

[0052] In one or more optional embodiments, the spraying treatment time is 1 to 20 minutes, preferably 3 to 10 minutes; the aging treatment time is 5 to 30 minutes, preferably 10 to 20 minutes.

[0053] In one or more optional embodiments, the specific surface area of ​​the carrier is 120–260 m². 2 / g, preferably 150-220m 2 / g; the water absorption rate of the carrier is 70% to 120%, preferably 80% to 100% (hereafter the water absorption rate is expressed as X, such as X = 0.9 if the water absorption rate is 90%; the mass of the spray carrier is expressed as T grams).

[0054] In this embodiment of the invention, the volume of the active component impregnation solution is 1.05×(1-percentage added to the pre-spray solution)×T~1.25×(1-percentage added to the pre-spray solution)×T ml, preferably 1.10×(1-percentage added to the pre-spray solution)×T~1.20×(1-percentage added to the pre-spray solution)×T ml.

[0055] Based on the same inventive concept, the present invention provides a hydrogenation catalyst prepared by the above-described preparation method.

[0056] In one or more optional embodiments, the hydrogenation catalyst contains 10-20 wt% molybdenum oxide, preferably 13-18 wt%; 1.5-8 wt% nickel oxide, preferably 2-6 wt%; 0-5 wt% cobalt oxide, preferably 0.5-2.5 wt%; and the balance is a support.

[0057] Based on the same inventive concept, the present invention provides an off-site presulfurization method for the above-mentioned hydrogenation catalyst, comprising:

[0058] The above-mentioned hydrogenation catalyst is placed in an impregnation pot, and the pre-sulfurized raw materials (including sulfiding agents and sulfidation auxiliaries) are mixed evenly with the hydrogenation catalyst by spraying.

[0059] In one or more optional embodiments, the pre-sulfurized raw material is a mixture of a sulfiding agent and a sulfidation accelerator. The amount of the sulfiding agent is 20-70% of the theoretical sulfur requirement of the hydrogenation catalyst, preferably 25-50%. The theoretical sulfur requirement of the hydrogenation catalyst refers to the amount of sulfur required for the complete conversion of the active metal components contained in the oxidized hydrogenation catalyst into sulfides such as Co9S8, MoS2, Ni3S2, and WS2. To ensure uniform mixing of the sulfiding agent and the oxidized hydrogenation catalyst, an appropriate amount of sulfidation accelerator can be added. The amount of the sulfidation accelerator is 0.5-40% of the weight of the hydrogenation catalyst, preferably 3-25%.

[0060] In this embodiment of the invention, the vulcanizing agent used is a conventional sulfur-containing substance in the art, which can be one or more of elemental sulfur and / or sulfur-containing compounds. It can be a single substance or a mixture. The sulfur-containing compound can be at least one of inorganic sulfur-containing compounds and organic sulfur-containing compounds. The inorganic sulfur-containing compound can be at least one of carbon disulfide and ammonium sulfide. The organic sulfur-containing compound can be at least one of monosulfide and polysulfide compounds, such as dimethyl disulfide, tert-butyl polysulfide, tert-nonyl polysulfide, thiourea, SZ-54 (commercial), thiols (such as n-butyl mercaptan, ethyl mercaptan), thiophenol, thioether, etc., or more.

[0061] In this embodiment of the invention, the vulcanizing aid used is a commonly used organic solvent in the art, such as one or more of hydrocarbon oils and organic carboxylic acid esters. The hydrocarbon oil used can be one or more of gasoline, kerosene, diesel, kerosene, white oil, industrial soybean oil, lubricating oil base oil, etc., preferably hydrocarbon oils obtained through secondary processing, such as those obtained through catalytic cracking, thermal cracking, etc. The organic carboxylic acid ester used can be an organic carboxylic acid ester containing 6 to 60 carbon atoms, preferably one or more of fatty acid glycerides, animal oils, rapeseed oil, peanut oil, soybean oil, cottonseed oil, etc.

[0062] Based on the same inventive concept, the present invention provides a presulfurized hydrogenation catalyst prepared by the above-mentioned external presulfurization method.

[0063] In one or more optional embodiments, the mass ratio of sulfur to active metal element in the presulfurized hydrogenation catalyst is 0.2 to 0.7, preferably 0.25 to 0.5.

[0064] Based on the same inventive concept, this invention provides a method for starting up catalytic cracking gasoline, comprising:

[0065] The above-mentioned presulfurized hydrogenation catalyst is loaded into the reactor;

[0066] After passing the airtightness test, under hydrogen circulation conditions, the reactor inlet temperature is increased at a rate of 15-25℃ / hour. When the catalyst bed temperature reaches 150-160℃, it is kept at a constant temperature for 3-5 hours; when the catalyst bed temperature reaches 180-220℃, it is kept at a constant temperature for 2-10 hours; when the catalyst bed temperature reaches 260-320℃, it is kept at a constant temperature for 4-10 hours.

[0067] Adjust the reaction conditions to meet the requirements of the system process, and switch to the feedstock oil for normal operation.

[0068] The following detailed description, in conjunction with embodiments, illustrates a method for preparing a hydrogenation catalyst and for pre-sulfurizing and starting up gasoline via catalytic cracking provided by the present invention.

[0069] Example 1

[0070] Preparation of hydrogenation catalysts:

[0071] The substrate used in the experiment was a clover-shaped alumina substrate with a specific surface area of ​​217 m². 2 / g, strength 156N / cm, water absorption rate 80%.

[0072] (1) First, prepare a citric acid aqueous solution for pretreatment: prepare 460 ml of a 0.3% citric acid aqueous solution;

[0073] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared citric acid aqueous solution to spray the carrier with atomized water for 5 min and place it for 8 min after spraying.

[0074] (3) Dissolve molybdenum oxide in an aqueous solution of phosphoric acid, add basic nickel carbonate and stir to dissolve, then add deionized water to adjust the solution volume to 8740 ml;

[0075] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 3 hours, dried at 100°C for 4 hours, and calcined at 500°C for 4 hours to obtain hydrogenation catalyst C1.

[0076] External presulfurization of hydrogenation catalyst:

[0077] (1) Mix the sulfiding agent (SZ-54, the amount of which is 40% of the theoretical sulfur required by the hydrogenation catalyst C1) and the sulfidation aid (white oil, the amount of which is 20% of the weight of the hydrogenation catalyst C1) evenly to obtain the pre-sulfided raw material.

[0078] (2) The hydrogenation catalyst C1 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C1 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs1.

[0079] Catalytic cracking gasoline start-up method:

[0080] (1) The pre-sulfurized hydrogenation catalyst Cs1 from outside the reactor is loaded into the reactor;

[0081] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0082] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 25℃ / hour. When the catalyst bed temperature reaches 150℃, it is kept at a constant temperature for 6 hours; when the catalyst bed temperature reaches 180℃, it is kept at a constant temperature for 3 hours; when the catalyst bed temperature reaches 285℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0083] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0084] Example 2

[0085] Preparation of hydrogenation catalysts:

[0086] The support used in the experiment was a cylindrical alumina-silica support with a specific surface area of ​​189 m². 2 / g, strength 145N / cm, water absorption rate 78%.

[0087] (1) First, prepare a potassium hydroxide aqueous solution for pretreatment: prepare 505 ml of 0.5% potassium hydroxide solution;

[0088] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared potassium hydroxide solution to spray the carrier with atomized solution for 3.5 min. After spraying, the placement time is 6 min.

[0089] (3) Add ammonium molybdate to a mixed solution of 5050ml ammonia water and 375g ethylenediaminetetraacetic acid, stir to dissolve, then add cobalt nitrate, nickel nitrate and potassium hydroxide in sequence, and add deionized water to adjust the solution volume to 7919ml;

[0090] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 3.5 h, dried at 120 °C for 4 h, and calcined at 480 °C for 4 h to obtain hydrogenation catalyst C2.

[0091] External presulfurization of hydrogenation catalyst:

[0092] (1) Mix the sulfiding agent (elemental sulfur, the amount of which is 35% of the theoretical sulfur required for hydrogenation catalyst C2) and the sulfidation aid (kerosene, the amount of which is 7% of the weight of hydrogenation catalyst C2) evenly to obtain the pre-sulfided raw material.

[0093] (2) The hydrogenation catalyst C2 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C2 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs2.

[0094] Catalytic cracking gasoline start-up method:

[0095] (1) The pre-sulfurized hydrogenation catalyst Cs2 from outside the reactor is loaded into the reactor;

[0096] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0097] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 20℃ / hour. When the catalyst bed temperature reaches 150℃, it is kept at a constant temperature for 5 hours; when the catalyst bed temperature reaches 185℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 280℃, it is kept at a constant temperature for 3 hours, and the catalyst sulfidation ends.

[0098] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0099] Example 3

[0100] Preparation of hydrogenation catalysts:

[0101] The substrate used in the experiment was a cloverleaf-shaped alumina-titanium oxide support with a specific surface area of ​​175 m². 2 / g, strength 148N / cm, water absorption rate 75%.

[0102] (1) First, prepare a potassium hydroxide aqueous solution for pretreatment: prepare 336 ml of 0.3% potassium hydroxide solution;

[0103] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared potassium hydroxide solution to spray the carrier with atomized solution for 4 min. After spraying, let it stand for 5 min.

[0104] (3) Add ammonium molybdate to a mixed solution of 4250ml ammonia and 413ml ethylenediamine, stir to dissolve, and then add nickel nitrate and potassium hydroxide in sequence. Add deionized water to adjust the solution volume to 8064ml.

[0105] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 2 hours, dried at 110°C for 3 hours, and calcined at 520°C for 4 hours to obtain hydrogenation catalyst C3.

[0106] External presulfurization of hydrogenation catalyst:

[0107] (1) Mix the sulfiding agent (sulfide and SZ-54, with a sulfur mass ratio of 1:2, and the amount used is 30% of the theoretical sulfur required by the hydrogenation catalyst C3) and the sulfidation aid (gasoline, with the amount used is 18% of the weight of the hydrogenation catalyst C3) evenly to obtain the pre-sulfided raw material.

[0108] (2) The hydrogenation catalyst C3 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C3 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs3.

[0109] Catalytic cracking gasoline start-up method:

[0110] (1) The pre-sulfurized hydrogenation catalyst Cs3 from outside the reactor is loaded into the reactor;

[0111] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0112] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 25℃ / hour. When the catalyst bed temperature reaches 155℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 210℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 320℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0113] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0114] Example 4

[0115] Preparation of hydrogenation catalysts:

[0116] The substrate used in the experiment was a four-leaf clover-shaped alumina-silica substrate with a specific surface area of ​​159 m². 2 / g, strength 131N / cm, water absorption rate 72%.

[0117] (1) First, prepare a citric acid aqueous solution for pretreatment: prepare 554 ml of a 0.4% citric acid aqueous solution;

[0118] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared citric acid aqueous solution to spray the carrier with atomized water for 2.5 min. After spraying, the placement time is 15 min.

[0119] (3) Dissolve ammonium molybdate in an aqueous solution of phosphoric acid, add nickel nitrate and stir to dissolve, then add deionized water to adjust the solution volume to 7366 ml;

[0120] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 4 hours, dried at 100°C for 5 hours, and calcined at 430°C for 6 hours to obtain hydrogenation catalyst C4.

[0121] External presulfurization of hydrogenation catalyst:

[0122] (1) Mix the sulfiding agent (tert-butyl polysulfide and SZ-54, with a sulfur mass ratio of 1:2 and a dosage of 20% of the theoretical sulfur required for the hydrogenation catalyst C4) and the sulfidation aid (diesel, with a dosage of 3% of the weight of the hydrogenation catalyst C4) evenly to obtain the pre-sulfided raw material.

[0123] (2) The hydrogenation catalyst C4 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C4 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs4.

[0124] Catalytic cracking gasoline start-up method:

[0125] (1) The pre-sulfurized hydrogenation catalyst Cs4 from outside the reactor is loaded into the reactor;

[0126] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0127] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 15℃ / hour. When the catalyst bed temperature reaches 150℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 185℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 290℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0128] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0129] Example 5

[0130] Preparation of hydrogenation catalysts:

[0131] The substrate used in the experiment was a cloverleaf-shaped alumina substrate with a specific surface area of ​​231 m². 2 / g, strength 135N / cm, water absorption rate 84%.

[0132] (1) First, prepare a potassium hydroxide aqueous solution for pretreatment: prepare 786 ml of 0.8% potassium hydroxide solution;

[0133] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared potassium hydroxide solution to spray the carrier with atomized solution for 6 min. After spraying, the carrier should be left for 16 min.

[0134] (3) Add ammonium molybdate to a mixed solution of 4960 ml ammonia and 505 g ethylenediamine, stir to dissolve, and then add cobalt nitrate, nickel nitrate and potassium hydroxide in sequence. Add deionized water to adjust the solution volume to 9042 ml.

[0135] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 4.5 h, dried at 120 °C for 3 h, and calcined at 480 °C for 5 h to obtain hydrogenation catalyst C5.

[0136] External presulfurization of hydrogenation catalyst:

[0137] (1) Mix the sulfiding agent (SZ-54, the amount of which is 45% of the theoretical sulfur required by the hydrogenation catalyst C5) and the sulfidation aid (lubricating oil base oil, the amount of which is 10% of the weight of the hydrogenation catalyst C5) evenly to obtain the pre-sulfided raw material.

[0138] (2) The hydrogenation catalyst C5 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C5 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs5.

[0139] Catalytic cracking gasoline start-up method:

[0140] (1) The pre-sulfurized hydrogenation catalyst Cs5 from outside the reactor is loaded into the reactor;

[0141] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0142] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 15℃ / hour. When the catalyst bed temperature reaches 160℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 220℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 290℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0143] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0144] Example 6

[0145] Preparation of hydrogenation catalysts:

[0146] The substrate used in the experiment was a four-leaf clover-shaped alumina-zirconia support with a specific surface area of ​​245 m². 2 / g, strength 112N / cm, water absorption rate 88%.

[0147] (1) First, prepare a potassium hydroxide aqueous solution for pretreatment: prepare 1047 ml of 0.6% potassium hydroxide solution;

[0148] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared potassium hydroxide solution to spray the carrier with atomized solution for 5.5 min. After spraying, the placement time is 10 min.

[0149] (3) Add ammonium molybdate to 6150ml of ammonia water, stir to dissolve, and then add nickel nitrate and potassium hydroxide in sequence. Add deionized water to adjust the solution volume to 9425ml.

[0150] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 2.5 h, dried at 110 °C for 5 h, and calcined at 470 °C for 5 h to obtain hydrogenation catalyst C6.

[0151] External presulfurization of hydrogenation catalyst:

[0152] (1) Mix the sulfiding agent (thiophenol and elemental sulfur in a sulfur mass ratio of 1:2, with an amount of 55% of the theoretical sulfur required for the hydrogenation catalyst C6) and the sulfidation aid (diesel fuel, with an amount of 25% of the weight of the hydrogenation catalyst C6) evenly to obtain the pre-sulfided raw material.

[0153] (2) The hydrogenation catalyst C6 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C6 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs6.

[0154] Catalytic cracking gasoline start-up method:

[0155] (1) The pre-sulfurized hydrogenation catalyst Cs6 from outside the reactor is loaded into the reactor;

[0156] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0157] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 20℃ / hour. When the catalyst bed temperature reaches 160℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 200℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 310℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0158] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0159] Example 7

[0160] Preparation of hydrogenation catalysts:

[0161] The substrate used in the experiment was a cloverleaf-shaped alumina substrate with a specific surface area of ​​258 m². 2 / g, strength 143N / cm, water absorption 95%.

[0162] (1) First, prepare a citric acid aqueous solution for pretreatment: prepare 1391 ml of a 0.7% citric acid aqueous solution;

[0163] (2) Weigh 10 kg of alumina and add it to a rotary impregnation pot. Use the prepared citric acid aqueous solution to spray the carrier with atomized water for 7 min and place it for 21 min after spraying.

[0164] (3) Dissolve molybdenum oxide in an aqueous solution of phosphoric acid, add basic nickel carbonate and stir to dissolve, then add deionized water to adjust the solution volume to 10199 ml;

[0165] (4) The active component impregnation solution prepared in step (3) is impregnated on the carrier treated in step (2), aged for 6 hours, dried at 100°C for 4 hours, and calcined at 450°C for 5 hours to obtain hydrogenation catalyst C7.

[0166] External presulfurization of hydrogenation catalyst:

[0167] (1) Mix the sulfiding agent (elemental sulfur and ammonium sulfide, with a sulfur mass ratio of 2:1 and an amount of 60% of the theoretical sulfur required for hydrogenation catalyst C7) and the sulfidation aid (white oil, with an amount of 12% of the weight of hydrogenation catalyst C7) evenly to obtain the pre-sulfided raw material.

[0168] (2) The hydrogenation catalyst C7 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst C7 by spraying to obtain the pre-sulfurized hydrogenation catalyst Cs7.

[0169] Catalytic cracking gasoline start-up method:

[0170] (1) The pre-sulfurized hydrogenation catalyst Cs7 from outside the reactor is loaded into the reactor;

[0171] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0172] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 15℃ / hour. When the catalyst bed temperature reaches 155℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 190℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 300℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0173] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0174] Comparative Example 1

[0175] Preparation of hydrogenation catalysts:

[0176] The substrate used in the experiment was a clover-shaped alumina substrate with a specific surface area of ​​217 m².2 / g, strength 156N / cm, water absorption rate 80%.

[0177] Molybdenum oxide was dissolved in an aqueous phosphoric acid solution, and basic nickel carbonate was added and stirred until dissolved. Deionized water was then added to adjust the solution volume to 9200 ml to obtain the active component solution. The prepared active component impregnation solution was impregnated onto a support, aged for 3 hours, dried at 100°C for 4 hours, and calcined at 500°C for 4 hours to obtain hydrogenation catalyst D1.

[0178] External presulfurization of hydrogenation catalyst:

[0179] (1) Mix the sulfiding agent (SZ-54, the amount of which is 40% of the theoretical sulfur required by the hydrogenation catalyst D1) and the sulfidation aid (white oil, the amount of which is 20% of the weight of the hydrogenation catalyst D1) evenly to obtain the pre-sulfided raw material.

[0180] (2) The hydrogenation catalyst D1 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst D1 by spraying to obtain the pre-sulfurized hydrogenation catalyst Ds1.

[0181] Catalytic cracking gasoline start-up method:

[0182] (1) The pre-sulfurized hydrogenation catalyst Ds1 from outside the reactor is loaded into the reactor;

[0183] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0184] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 25℃ / hour. When the catalyst bed temperature reaches 150℃, it is kept at a constant temperature for 6 hours; when the catalyst bed temperature reaches 180℃, it is kept at a constant temperature for 3 hours; when the catalyst bed temperature reaches 285℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0185] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0186] Comparative Example 2

[0187] Preparation of hydrogenation catalysts:

[0188] The substrate used in the experiment was a cloverleaf-shaped alumina-titanium oxide support with a specific surface area of ​​175 m². 2 / g, strength 148N / cm, water absorption 75%. Ammonium molybdate was added to a mixed solution of 4250ml ammonia and 413ml ethylenediamine, stirred to dissolve, and then nickel nitrate and potassium hydroxide were added sequentially. Deionized water was added to adjust the solution volume to 8400ml to obtain the active component solution. The prepared active component impregnation solution was impregnated onto a support, aged for 2h, dried at 110℃ for 3h, and calcined at 520℃ for 4h to obtain hydrogenation catalyst D2.

[0189] External presulfurization of hydrogenation catalyst:

[0190] (1) Mix the sulfiding agent (sulfide and SZ-54, with a sulfur mass ratio of 1:2, and the amount used is 30% of the theoretical sulfur required by the hydrogenation catalyst D2) and the sulfidation aid (gasoline, with the amount used is 18% of the weight of the hydrogenation catalyst D2) evenly to obtain the pre-sulfided raw material.

[0191] (2) The hydrogenation catalyst D2 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst D2 by spraying to obtain the pre-sulfurized hydrogenation catalyst Ds2.

[0192] Catalytic cracking gasoline start-up method:

[0193] (1) The pre-sulfurized hydrogenation catalyst Ds2 from outside the reactor is loaded into the reactor;

[0194] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0195] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 25℃ / hour. When the catalyst bed temperature reaches 155℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 210℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 320℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0196] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0197] Comparative Example 3

[0198] Preparation of hydrogenation catalysts:

[0199] The substrate used in the experiment was a cloverleaf-shaped alumina substrate with a specific surface area of ​​231 m². 2 / g, strength 135N / cm, water absorption rate 84%.

[0200] Ammonium molybdate was added to a mixed solution of 4960 ml ammonia and 505 g ethylenediamine and stirred until dissolved. After dissolution, cobalt nitrate, nickel nitrate, and potassium hydroxide were added sequentially, and deionized water was added to adjust the solution volume to 9828 ml to obtain the active component solution. The prepared active component impregnation solution was impregnated onto a support, aged for 4.5 h, dried at 120 °C for 3 h, and calcined at 480 °C for 5 h to obtain the hydrogenation catalyst D3.

[0201] External presulfurization of hydrogenation catalyst:

[0202] (1) Mix the sulfiding agent (SZ-54, the amount of which is 45% of the theoretical sulfur required by the hydrogenation catalyst D3) and the sulfidation aid (lubricating oil base oil, the amount of which is 10% of the weight of the hydrogenation catalyst D3) evenly to obtain the pre-sulfided raw material.

[0203] (2) The hydrogenation catalyst D3 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst D3 by spraying to obtain the pre-sulfurized hydrogenation catalyst Ds3.

[0204] Catalytic cracking gasoline start-up method:

[0205] (1) The pre-sulfurized hydrogenation catalyst Ds3 from outside the reactor is loaded into the reactor;

[0206] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0207] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 15℃ / hour. When the catalyst bed temperature reaches 160℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 220℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 290℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0208] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0209] Comparative Example 4

[0210] Preparation of hydrogenation catalysts:

[0211] The substrate used in the experiment was a cloverleaf-shaped alumina substrate with a specific surface area of ​​258 m². 2 / g, strength 143N / cm, water absorption 95%.

[0212] Molybdenum oxide was dissolved in an aqueous phosphoric acid solution, and basic nickel carbonate was added and stirred until dissolved. Deionized water was then added to adjust the solution volume to 11590 ml to obtain the active component solution. The prepared active component impregnation solution was impregnated onto a support, aged for 6 hours, dried at 100°C for 4 hours, and calcined at 450°C for 5 hours to obtain the hydrogenation catalyst D4.

[0213] External presulfurization of hydrogenation catalyst:

[0214] (1) Mix the sulfiding agent (elemental sulfur and ammonium sulfide, with a sulfur mass ratio of 2:1 and an amount of 60% of the theoretical sulfur required by the hydrogenation catalyst D4) and the sulfidation aid (white oil, with an amount of 12% of the weight of the hydrogenation catalyst D4) evenly to obtain the pre-sulfided raw material.

[0215] (2) The hydrogenation catalyst D4 is placed in a rotary impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst D4 by spraying to obtain the pre-sulfurized hydrogenation catalyst Ds4.

[0216] Catalytic cracking gasoline start-up method:

[0217] (1) The pre-sulfurized hydrogenation catalyst Ds4 from outside the reactor is loaded into the reactor;

[0218] (2) The device underwent nitrogen gas tightness testing, hydrogen replacement, and hydrogen gas tightness testing, and the tests were passed.

[0219] (3) Under hydrogen circulation, the reactor inlet temperature is increased at a rate of 15℃ / hour. When the catalyst bed temperature reaches 155℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 190℃, it is kept at a constant temperature for 4 hours; when the catalyst bed temperature reaches 300℃, it is kept at a constant temperature for 4 hours, and the catalyst sulfidation ends.

[0220] (4) Adjust the system process conditions to the reaction conditions and switch the feed oil for normal operation.

[0221] Test Example 1

[0222] Catalyst evaluation process conditions:

[0223] The feedstock was a product from the first stage of hydrogenation of catalytic cracked gasoline. The reaction conditions were: reaction pressure 3.0 MPa, liquid hourly space velocity 2.0 h⁻¹. -1 The reaction temperature was 330℃, and the hydrogen-to-oil volume ratio was 300:1. The components and their contents (in mass percentage) of the hydrogenation catalysts prepared in Examples 1-7 and Comparative Examples 1-4 are shown in Table 1.

[0224] Table 1. Mass content of each component in the catalyst

[0225]

[0226]

[0227] The hydrogenation catalysts prepared in Examples 1-7 and Comparative Examples 1-4 were characterized by elemental distribution analysis using SEM-EDS, revealing the distribution of active components on the catalysts. Table 2 shows the content of active components at different positions in the hydrogenation catalysts prepared in Examples 1-7 and Comparative Examples 1-4. The characterization results of hydrogenation catalyst C1 prepared in Example 1 are shown in the figure below. Figure 1 As shown in the figure, the characterization results of the hydrogenation catalyst C5 prepared in Example 5 are as follows. Figure 2 As shown.

[0228] Table 2. Percentage (%) of metal content of active components at different locations in the catalyst to the total content of active components.

[0229]

[0230] The pre-sulfurized hydrogenation catalysts Cs5 and Ds3 prepared in Example 5 and Comparative Example 3 were evaluated for 300 hours, respectively. The raw materials were catalytic cracking gasoline first-stage hydrogenation products, and the properties of the raw materials are shown in Table 3. The catalyst evaluation was carried out in a 150 ml isothermal bed hydrogenation reactor. Samples were taken every 12 hours to analyze the bromine index, sulfur content, and nitrogen content of the product. The average data of the catalyst evaluation for 300 hours are shown in Table 4.

[0231] Table 3 Hydrogenation Feedstock Indicators

[0232]

[0233] Table 4. Average data of catalysts Cs5 and Ds3 after 300 hours of evaluation.

[0234]

[0235] As can be seen from the characterization results in Table 2, the catalyst prepared using the hydrogenation catalyst preparation and external pre-sulfurization method of the present invention has a more reasonable concentration distribution of active components; Figure 1 and Figure 2 It can be seen that the catalysts prepared by both the acid method and the alkaline method have good distribution of active components. As can be seen from the evaluation results in Table 4, under the same evaluation process conditions, the hydrogenation product of the pre-sulfurized hydrogenation catalyst Cs5 prepared in Example 5 has lower bromine value, total sulfur, and total nitrogen compared with Comparative Example 3, indicating that the catalyst prepared by the hydrogenation catalyst preparation and external pre-sulfurization method of the present invention has more beneficial hydrogenation refining performance.

[0236] Although specific embodiments of the invention have been described in detail, those skilled in the art will understand that various modifications and substitutions can be made to those details based on all the teachings disclosed, and all such changes are within the scope of protection of this invention. The full scope of this invention is given by the appended claims and any equivalents thereof.

Claims

1. A method for preparing a hydrogenation catalyst, characterized in that, include: Step (1): Add the carrier to the impregnation pot and spray the carrier with a pre-spraying solution for 1-20 min; after spraying, perform aging treatment for 5-30 min; the carrier is directly used for catalyst preparation without drying and calcination after spraying and aging. Step (2): The active component impregnation solution is impregnated onto the carrier treated in step (1), aged, dried, and calcined; The specific surface area of ​​the carrier is 120~260m². 2 / g, the water absorption rate of the carrier is 70%~120%; The volume of the active component impregnation solution is 1.05 × (1 - percentage added to the pre-spray solution) × T ~ 1.25 × (1 - percentage added to the pre-spray solution) × T ml, wherein the water absorption rate of the carrier is expressed as X, and the mass of the carrier is expressed as T grams; The volume percentage of the pre-spray solution is 1% to 20% of the total impregnation liquid volume, where the total impregnation liquid volume is the sum of the volume of the pre-spray solution and the volume of the active component impregnation liquid.

2. The method as described in claim 1, characterized in that, The pre-spraying solution is an aqueous solution of citric acid or a potassium hydroxide solution.

3. The method as described in claim 2, characterized in that: When the pre-spraying solution is an aqueous solution of citric acid, a salt containing the active component is added to an aqueous solution of inorganic acid to prepare an active component impregnation solution for impregnation onto the carrier. or, When the pre-spraying solution is a potassium hydroxide solution, potassium hydroxide, ammonia, polyamine complexing agent and deionized water are mixed to prepare a composite solvent. Salt containing active components is added to the composite solvent to prepare an active component impregnation solution for impregnation on the carrier.

4. The method as described in claim 3, characterized in that, The active components are molybdenum, cobalt, and nickel.

5. The method as described in claim 4, characterized in that, The active component salt is ammonium molybdate and / or molybdenum oxide, cobalt nitrate and / or cobalt acetate, nickel nitrate and / or nickel acetate.

6. The method as described in claim 1, characterized in that, The spraying treatment time is 3-10 minutes; the aging treatment time is 10-20 minutes.

7. The method as described in claim 1, characterized in that, The specific surface area of ​​the carrier is 150~220m². 2 / g; the water absorption rate of the carrier is 80%~100%.

8. The method as described in claim 1, characterized in that, The volume of the active component impregnation solution is 1.10 × (1 - percentage added to the pre-spray solution) × T ~ 1.20 × (1 - percentage added to the pre-spray solution) × T ml.

9. The method as described in claim 1, characterized in that, The volume percentage of the pre-spray solution is 5% to 10% of the total impregnation solution volume.

10. A hydrogenation catalyst prepared by the method according to any one of claims 1 to 9.

11. The hydrogenation catalyst according to claim 10, characterized in that, The hydrogenation catalyst contains 10-20 wt% molybdenum oxide, 1.5-8 wt% nickel oxide, 0-5 wt% cobalt oxide, and the remainder is a support.

12. The hydrogenation catalyst according to claim 11, characterized in that, The hydrogenation catalyst contains 13-18 wt% molybdenum oxide, 2-6 wt% nickel oxide, and 0.5-2.5 wt% cobalt oxide, with the remainder being a support.

13. The method for pre-sulfurization of the hydrogenation catalyst outside the apparatus according to any one of claims 10-12, characterized in that, include: The hydrogenation catalyst according to any one of claims 10 to 12 is placed in an impregnation pot, and the pre-sulfurized raw material is mixed evenly with the hydrogenation catalyst by spraying.

14. The external pre-vulcanization method as described in claim 13, characterized in that, The pre-vulcanizing raw material is a mixture of vulcanizing agent and vulcanizing auxiliaries; The amount of the sulfiding agent used is 20-70% of the theoretical sulfur requirement of the hydrogenation catalyst; The amount of the sulfidation aid is 0.5 to 40% of the weight of the hydrogenation catalyst.

15. The external pre-vulcanization method as described in claim 14, characterized in that, The amount of the sulfiding agent is 25-50% of the theoretical sulfur requirement of the hydrogenation catalyst; the amount of the sulfidation aid is 3-25% of the weight of the hydrogenation catalyst.

16. The presulfurized hydrogenation catalyst prepared by the external presulfurization method according to any one of claims 13 to 15.

17. The presulfurized hydrogenation catalyst as described in claim 16, characterized in that, In the pre-sulfurized hydrogenation catalyst, the mass ratio of sulfur to active metal element is 0.2~0.

7.

18. The presulfurized hydrogenation catalyst as described in claim 17, characterized in that, In the pre-sulfurized hydrogenation catalyst, the mass ratio of sulfur to active metal element is 0.25~0.

5.

19. A method for starting up catalytic cracking gasoline, characterized in that, include: The presulfurized hydrogenation catalyst according to any one of claims 16 to 18 is loaded into the reactor; After passing the airtightness test, under hydrogen circulation conditions, the reactor inlet temperature is increased at a rate of 15~25℃ / hour. When the catalyst bed temperature reaches 150~160℃, it is kept at a constant temperature for 3~5 hours; when the catalyst bed temperature reaches 180~220℃, it is kept at a constant temperature for 2~10 hours; when the catalyst bed temperature reaches 260~320℃, it is kept at a constant temperature for 4~10 hours. Adjust the reaction conditions to meet the requirements of the system process, and switch to the feedstock oil for normal operation.

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