A method for catalytic hydroprocessing of fuel oil slurry

Abstract

This invention discloses a method for hydrotreating catalytic cracking slurry. A fixed-bed hydrotreating process is employed, comprising: in the presence of hydrogen, the catalytic cracking slurry sequentially contacts a hydrotreating protectant, a hydrotreating transition catalyst, and a hydrodesulfurization catalyst to undergo a hydrotreating reaction, yielding hydrotreated oil. The hydrotreating protectant comprises an alumina support with a most probable pore size of 40–100 nm, molybdenum oxide, and cobalt oxide. The hydrotreating transition catalyst comprises an alumina support containing additives and MoO3 and CoO. The support has a bimodal pore size distribution, with smaller pores concentrated in the 10–40 nm range and larger pores concentrated in the 150–400 nm range. This method eliminates the diffusion resistance during the adsorption and reaction of large molecules on the catalyst surface during the hydrotreating of catalytic cracking slurry, increases the capacity for more deposits such as coke, extends the operating cycle of the unit, and facilitates hydrodesulfurization and other reactions. It also increases the content of tricyclic and tetracyclic aromatics in the hydrotreated oil, making it a high-quality feedstock for needle coke production.

Description

Technical Field

[0001] This invention belongs to the field of hydrogenation technology, and specifically relates to a method for hydrogenating catalytic oil slurry. Background Technology

[0002] With the continuous deterioration and increasing heaviness of petroleum resources, the market demand for diversified and lightweight petrochemical products is growing. Processing low-quality, heavy crude oil has become a significant challenge for refineries worldwide. Catalytic cracking technology is one of the three main processes for deep processing of heavy oil and a key technology for lightweighting feedstocks, exhibiting strong adaptability to various feedstocks. Currently, some catalytic cracking units can directly process atmospheric residue or blend with some vacuum residue, leading to problems such as a deterioration in the distribution of catalytic cracking products. To increase unit throughput, reduce energy consumption, and increase lightweight products, external slurry loading is a good solution, but this generates a large amount of catalytic cracking slurry as a byproduct. As a low-value-added product of the catalytic cracking process, catalytic cracking slurry is characterized by high density, high carbon residue, high viscosity, and high aromatic content, and contains residual catalyst particles and coke, making its processing and utilization difficult. Therefore, how to process and utilize catalytic cracking slurry has become a critical issue that refineries urgently need to address.

[0003] Catalytic cracking slurry oil, rich in aromatics, is an ideal raw material for the preparation of high-end carbon-based materials such as needle coke. Needle coke is characterized by high crystallinity, high strength, high graphitization, low thermal expansion, and low ablation, and is mainly used in ultra-high power graphite electrodes and lithium-ion battery anode materials. As a raw material for needle coke production, catalytic cracking slurry oil typically requires low sulfur, low nitrogen, low ash content, and high aromatic content, especially high levels of tricyclic and tetracyclic aromatics. However, catalytic cracking slurry oil has high density, high carbon residue, high viscosity, high aromatic content, and contains residual catalyst particles and coke, making it difficult to utilize. Currently, high-quality low-sulfur slurry oil resources are very scarce, while inferior slurry oil has a high sulfur content (1.0 wt%–2.0 wt%). Needle coke products have strict requirements for sulfur content (≤0.5 wt%), and processing with conventional residue hydrotreating catalysts results in excessive aromatic loss. Currently, there is limited research on hydrogenation catalysts specifically for catalytic cracking slurry oil. Therefore, developing a catalyst suitable for hydrogenation of catalytic cracking slurry oil is of great significance.

[0004] CN103013567A discloses a method for producing needle coke feedstock from catalytic cracking slurry. The method includes a protected zone and a hydrotreating reaction zone. The protected zone is filled with an adsorbent capable of adsorbing catalytic cracking catalyst powder. The hydrotreating reaction zone is filled sequentially with a hydrotreating protective agent, a hydrodemetallizing agent, and a hydrodesulfurizing agent according to the flow direction of the reaction stream. The catalytic cracking slurry first enters the protected zone, adsorbing most of the catalytic cracking catalyst powder, and then mixes with hydrogen into a heating furnace. After heating, it enters the hydrotreating reaction zone for hydrotreating. The hydroprotectant is a Raschig ring and is a conventional residue hydroprotectant. The hydrodemetallizing agent contains an alumina support and molybdenum and / or tungsten supported on the support, as well as nickel and / or cobalt. The pore distribution of the support is such that the pore volume of the pores with a diameter of 100-200 angstroms (10-20 nm) accounts for 70%-98% of the total pore volume. The hydrodesulfurizing agent contains a support and molybdenum and / or tungsten supported on the support, as well as nickel and / or cobalt. The support is alumina and optionally silicon oxide. The pore distribution of the support is such that the pore volume of the pores with a diameter of 60-100 angstroms (6-10 nm) accounts for 75%-98% of the total pore volume. The aforementioned hydrodemetallizing and hydrodesulfurizing agents are all conventional residue hydrotreating catalysts. Although they can be used for hydrotreating catalytic cracking slurry, catalytic cracking slurry has a low metal content, low metal deposits, small pore size of the support, and low macropore volume. During the hydrotreating reaction, the adsorption and reaction of macromolecules such as colloids and asphaltenes in the catalytic cracking slurry will be affected by diffusion resistance. At the same time, the continuous deposition of carbon during the hydrotreating process can easily cause pore blockage, and the carbon deposits will be deposited on the downstream desulfurization catalyst, ultimately leading to unit shutdown.

[0005] Because catalytic cracking slurry feedstock differs from conventional residue feedstock, existing conventional residue hydrotreating catalysts still present the aforementioned problems for catalytic cracking slurry feedstock. Therefore, there is an urgent need to develop a process method suitable for catalytic cracking slurry hydrotreating. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for hydrotreating catalytic cracking slurry oil. This method eliminates the diffusion resistance during the adsorption and reaction of macromolecules on the catalyst surface during the hydrotreating process of catalytic cracking slurry oil, increases the capacity to accommodate more deposits such as coke, extends the operating cycle of the unit, and simultaneously facilitates hydrodesulfurization and other reactions. Furthermore, it increases the content of tricyclic and tetracyclic aromatics in the hydrotreated oil, making it a high-quality feedstock for needle coke production.

[0007] The deconsolidated catalytic cracking slurry contains fewer metallic impurities but higher contents of gums and asphaltenes (4.0%–15.0%). Asphaltenes molecules are mainly composed of 5 to 7 lamellar fused aromatic rings with a size of 12–16 angstroms (1.2–1.6 nm), and these molecules are prone to aggregation. Therefore, conventional residue hydrotreating protectants and hydrodemetallizing catalysts are not very suitable for hydrotreating catalytic cracking slurry. The inventors discovered that developing a hydrotreating protectant with suitable large pore size and distribution, and a hydrotreating transition agent with suitable bimodal pore size distribution, and using them in a graded manner, not only facilitates the diffusion of large molecules and accommodates more deposits such as coke, but also promotes the hydrogenation reaction of small sulfur-containing compounds such as thiols and thioethers. This achieves the initial removal of sulfur impurities from the catalytic cracking slurry, playing a crucial role in ensuring that the performance of downstream catalysts is not affected by impurities such as coke deposits, thus guaranteeing the long-term operation of the unit.

[0008] This invention provides a method for hydrotreating catalytic cracking slurry oil, employing a fixed-bed hydrotreating process, comprising: in the presence of hydrogen, sequentially contacting a hydrotreating protectant, a hydrotreating transition catalyst, and a hydrodesulfurization catalyst to carry out a hydrotreating reaction, thereby obtaining hydrotreating product oil;

[0009] The hydrogenation protective agent mentioned above includes a support and a hydrogenation active metal, wherein an alumina support is used, and the hydrogenation active metal includes molybdenum oxide and cobalt oxide. The properties of the alumina support are as follows: the most probable pore size is 40-100 nm, preferably 50-70 nm, and the pore volume occupied by the channels from (most probable pore size - 30) nm to (most probable pore size + 30) nm accounts for more than 75% of the total pore volume, preferably 75%-90%.

[0010] The hydrogenation transition catalyst includes an alumina support containing promoters and MoO3 and CoO. The support has a bimodal pore size distribution, with smaller pore sizes concentrated in the range of 10–40 nm, and the pore volume of pores with a size of 10–40 nm accounting for 20%–40% of the total pore volume. Larger pore sizes are concentrated in the range of 150–400 nm, and the pore volume of pores with a size of 150–400 nm accounts for 30%–50% of the total pore volume.

[0011] In this invention, based on the mass of the hydrogenation protectant, the mass content of MoO3 is 2.0% to 7.0%, and the mass content of CoO is 0.3% to 1.7%.

[0012] In this invention, based on the mass of the hydrogenation protective agent, the mass content of the alumina carrier is 91.3% to 97.7%.

[0013] In this invention, the alumina support in the hydrogenation protective agent has a pore volume of 1.00–1.40 cm³. 3 / g, preferably 1.10~1.30cm 3 / g.

[0014] In this invention, the alumina support in the hydrogenation protective agent has a specific surface area of ​​120–180 m². 2 / g, preferably 130-170m 2 / g.

[0015] In this invention, the hydrogenation protectant is preferably shaped like a four-leaf impeller or a four-leaf clover.

[0016] The present invention also provides a method for preparing the above-mentioned hydrogenation protective agent, comprising the following steps:

[0017] a) The first aluminum source, the second aluminum source and the third aluminum source are mixed with water to obtain a slurry, and then the slurry is ground.

[0018] b) Add purified water to the slurry obtained in step a) and stir;

[0019] c) Add modifier, pH adjuster and optional dispersant to the material obtained in step b) to obtain a mixed slurry, and then perform hydrothermal treatment on the mixed slurry;

[0020] d) The material obtained in step c) is dried to obtain alumina dry adhesive;

[0021] e) Mix the alumina dry adhesive obtained in step d) with the binder, shape, dry, and calcine to obtain the carrier;

[0022] f) Impregnate the carrier obtained in step e) with an impregnation solution containing molybdenum and cobalt, and then dry and calcine to obtain the hydrogenation protectant.

[0023] In the method of the present invention, in step a), the first aluminum source is aluminum oxide trihydrate.

[0024] In the method of this invention, in step a), the second aluminum source is alumina dry adhesive with a water content of less than 35% by mass fraction. The alumina dry adhesive can be a product of dehydration of alumina hydrate; it can be completely dehydrated alumina or partially dehydrated alumina, such as monohydrated alumina.

[0025] In the method of this invention, in step a), the third aluminum source is an aluminum-containing salt compound, which can be an acidic aluminum salt, a basic aluminate, and / or aluminate. The third aluminum source can be selected from at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, sodium aluminate, etc.

[0026] In the method of the present invention, in step a), the mass ratio of the first aluminum source, the second aluminum source and the third aluminum source is 30-66:33-60:1-10.

[0027] In the method of the present invention, in step a), the amount of water added is 100% to 150% of the total mass of the first aluminum source, the second aluminum source and the third aluminum source.

[0028] In the method of the present invention, in step a), the slurry is ground until the particle size in the slurry is 4 to 20 μm, calculated as the median particle size D50.

[0029] In the method of the present invention, in step b), the slurry obtained in step a) is mixed with purified water (preferably deionized water) so that the total mass of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

[0030] In the method of the present invention, in step c), the pH adjuster can be an alkaline substance (such as at least one of sodium hydroxide, ammonia, sodium bicarbonate, ammonium carbonate, etc.) or an acidic substance (such as at least one of acetic acid, citric acid, nitric acid, etc.). The added pH adjuster is adjusted according to the properties of the slurry to control the pH value of the mixed slurry in step c) to be 8.5 to 12.0.

[0031] In the method of this invention, in step c), the dispersant is selected from at least one of hydrophilic dispersants. The dispersant can be a nonionic surfactant with an HLB value (Hydrophile-Lipophile Balance Number) of 10 to 20. The amount of dispersant added is less than 10% of the mass of the material obtained in step b), preferably 0.01% to 10%. The nonionic surfactant dispersant is preferably at least one of Tween-80, lauryl alcohol polyoxyethylene ether, and methyl glucose polyoxyethylene ether. The modifier is preferably at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium ethylenediaminetetraacetate, sodium gluconate, and sodium tartrate. The amount of the modifier added is 0.01% to 6% of the mass of the material obtained in step b), for example, but not limited to: 0.1%, 0.2%, 0.5%, 0.6%, 0.8%, 1.0%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, etc.

[0032] In the method of the present invention, in step c), the hydrothermal treatment conditions are as follows: temperature is 220-280℃, and time is 5-12 hours.

[0033] In the method of this invention, in step d), before drying, the material obtained in step c) can be subjected to steps such as filtration and washing. Conventional filtration and washing methods are sufficient. The drying conditions are as follows: drying temperature is 100–180℃, and drying time is 4–10 hours.

[0034] In the method of this invention, in step e), the binder is selected from at least one of inorganic acid, organic acid, cellulose, and resin, wherein the inorganic acid can be nitric acid, and the organic acid is selected from at least one of acetic acid, citric acid, and tartaric acid. The cellulose is at least one of hydroxypropyl cellulose or methylcellulose, and the resin is at least one of phenolic resin or ethylene-vinyl acetate resin. The amount of binder added is 0.1% to 10% of the mass of the alumina dry adhesive.

[0035] In the method of this invention, in step e), a molding aid, such as an extrusion aid, may be added depending on the molding process. The extrusion aid is selected from guar gum powder; the amount of extrusion aid added is 0.5% to 6.0% of the mass of the alumina dry adhesive obtained in step d).

[0036] In the method of this invention, step e) does not require the addition of pore-forming materials, such as pore expanders. The pore-forming material refers to the material added during the carrier preparation process. During the molding process, the pore expander molecules are encapsulated by alumina powder particles. After high-temperature calcination, the pore expander molecules are oxidized or undergo other chemical reactions to generate gas and escape, leaving behind the previously occupied space, thus forming large pores. Examples of such materials include carbon black and starch.

[0037] In the method of the present invention, in step e), the shaped material can be a four-leaf stalk or a four-leaf clover.

[0038] In the method of this invention, in step e), the drying conditions after molding are as follows: drying temperature is 100–180°C, and drying time is 4–12 hours; the calcination conditions after molding are as follows: calcination temperature is 500–800°C, and calcination time is 3–12 hours. The calcination atmosphere can be an oxygen-containing gas, such as air.

[0039] In the method of this invention, in step f), the impregnation solution containing molybdenum and cobalt contains cobalt at a concentration of 0.2–1.6 g / 100 mL (calculated as cobalt oxide) and molybdenum at a concentration of 1.6–6.3 g / 100 mL (calculated as molybdenum oxide). The molybdenum source can be at least one of ammonium molybdate and molybdenum trioxide. The cobalt source can be at least one of cobalt nitrate and basic cobalt carbonate.

[0040] In the method of the present invention, in step f), the impregnation is preferably carried out by saturation impregnation.

[0041] In the method of this invention, in step f), the drying conditions after impregnation are as follows: drying temperature is 100–180°C, and drying time is 4–12 hours; the calcination conditions are as follows: calcination temperature is 450–600°C, and calcination time is 3–6 hours. The calcination atmosphere is an oxygen-containing atmosphere, such as air.

[0042] In this invention, the hydrogenation transition catalyst comprises an alumina support containing promoters and MoO3 and CoO. The support has a bimodal pore size distribution, with smaller pore sizes concentrated in the range of 10–40 nm, and the pore volume of channels with pore sizes of 10–40 nm accounting for 20%–40% of the total pore volume. Larger pore sizes are concentrated in the range of 150–400 nm, and the pore volume of channels with pore sizes of 150–400 nm accounting for 30%–50% of the total pore volume.

[0043] In this invention, the pore volume of the support in the hydrogenation transition catalyst is 0.95–1.35 cm³. 3 / g, preferably 1.00~1.25cm 3 / g.

[0044] In this invention, the specific surface area of ​​the support in the hydrogenation transition catalyst is 110–175 m². 2 / g, preferably 130-170m 2 / g.

[0045] In this invention, based on the mass of the hydrogenation transition catalyst, the content of MoO3 is 4.0% to 10.0%, and the content of CoO is 0.8% to 2.5%.

[0046] In this invention, the hydrogenation transition catalyst is preferably clover-shaped.

[0047] In this invention, in the hydrogenation transition catalyst, the alumina support containing the auxiliary agent is preferably one or more of fluorine, phosphorus, silicon or boron; the content of the auxiliary agent, calculated by element, accounts for 0.2% to 10% of the total mass of alumina in the support, preferably 1% to 6%.

[0048] In this invention, the preparation method of the above-mentioned hydrogenation transition catalyst includes the following steps:

[0049] A) The first aluminum source, the second aluminum source, and the third aluminum source are mixed with water to obtain a slurry, and then the slurry is ground.

[0050] B) Add purified water to the slurry obtained in step A) and stir;

[0051] C) Add pH adjuster, modifier, auxiliary agent precursor and optional dispersant to the material obtained in step B) to obtain a mixed slurry, and then perform hydrothermal treatment on the mixed slurry;

[0052] D) The material obtained in step C) is dried to obtain alumina dry adhesive;

[0053] E) Mix the alumina dry adhesive obtained in step D) with the binder, shape, dry, and calcine to obtain the carrier;

[0054] F) Impregnate the support obtained in step E) with an impregnation solution containing molybdenum and cobalt, and then dry and calcine to obtain the hydrogenation transition catalyst.

[0055] In the method of the present invention, in step A), the first aluminum source is aluminum oxide trihydrate.

[0056] In the method of this invention, in step A), the second aluminum source is alumina dry adhesive with a water content of less than 35% by mass fraction. The alumina dry adhesive can be a product of dehydration of alumina hydrate; it can be completely dehydrated alumina or partially dehydrated alumina, such as monohydrated alumina.

[0057] In the method of this invention, in step A), the third aluminum source is an aluminum-containing salt compound, which can be an acidic aluminum salt, a basic aluminate, and / or aluminate. The third aluminum source can be selected from at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, sodium aluminate, etc.

[0058] In the method of the present invention, in step A), the mass ratio of the first aluminum source, the second aluminum source and the third aluminum source is 30-66:33-60:1-10.

[0059] In the method of the present invention, in step A), the amount of water added is 100% to 150% of the total mass of the first aluminum source, the second aluminum source, and the third aluminum source.

[0060] In the method of the present invention, in step A), the slurry is ground until the particle size in the slurry is 4-20 μm, calculated as the median particle size D50.

[0061] In the method of the present invention, in step B), the slurry obtained in step A) is mixed with purified water (preferably deionized water) so that the total mass of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

[0062] In the method of the present invention, in step C), the pH adjuster can be an alkaline substance (such as at least one of sodium hydroxide, ammonia, sodium bicarbonate, ammonium carbonate, etc.) or an acidic substance (such as at least one of acetic acid, citric acid, nitric acid, etc.). The added pH adjuster is adjusted according to the properties of the slurry to control the pH range of the mixed slurry in step C) to be 9.0 to 12.5.

[0063] In the method of this invention, in step C), the dispersant is selected from at least one of hydrophilic dispersants. The dispersant can be a nonionic surfactant with an HLB value (Hydrophile-Lipophile Balance Number) of 10 to 20. The amount of dispersant added is less than 10% of the mass of the material obtained in step b), preferably 0.01% to 10%. The nonionic surfactant dispersant is preferably at least one of Tween-80, lauryl alcohol polyoxyethylene ether, and methyl glucose polyoxyethylene ether. The modifier is preferably at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium ethylenediaminetetraacetate, sodium gluconate, and sodium tartrate. The amount of the modifier added is 0.01% to 10% of the mass of the material obtained in step B), preferably 0.01% to 6%, and examples, but not limited to: 0.1%, 0.2%, 0.5%, 0.6%, 0.8%, 1.0%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, etc.

[0064] In the method of this invention, in step C), the additive is preferably one or more of fluorine, phosphorus, silicon, or boron, with silicon being the most preferred. Based on the total mass of the first aluminum source, the second aluminum source, and the third aluminum source, the amount of additive (calculated as oxide) added accounts for 0.2% to 10% of the total mass of alumina, preferably 1% to 6%. The fluorine precursor can be at least one of hydrofluoric acid, ammonium fluoride, boron trifluoride, and sodium fluorosilicate; the phosphorus precursor can be at least one of phosphoric acid, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate; the silicon precursor can be at least one of silica sol, water glass, and fluorosilicic acid; and the boron precursor can be at least one of boric acid, sodium borate, ammonium borate, and ammonium metaborate.

[0065] In the method of the present invention, in step C), the conditions for hydrothermal treatment are as follows: temperature is 200-260℃, and hydrothermal time is 4-10 hours.

[0066] In the method of this invention, before drying in step D), the material obtained in step c) can be subjected to filtration and washing. Conventional filtration and washing methods can be used.

[0067] In the method of the present invention, in step D), the drying conditions are: drying temperature of 100-180℃, drying time of 4-12 hours.

[0068] In the method of this invention, in step E), the binder is selected from at least one of inorganic acid, organic acid, cellulose, and resin, wherein the inorganic acid can be nitric acid, and the organic acid is selected from at least one of acetic acid, citric acid, and tartaric acid. The cellulose is at least one of hydroxypropyl cellulose or methylcellulose, and the resin is at least one of phenolic resin or ethylene-vinyl acetate resin. The amount of binder added is 0.1% to 10% of the mass of the alumina dry adhesive.

[0069] In the method of this invention, in step E), a molding aid, such as an extrusion aid, may be added depending on the molding process. The extrusion aid is selected from guar gum powder; the amount of extrusion aid added is 0.5% to 6.0% of the mass of the alumina dry adhesive obtained in step D).

[0070] In the method of this invention, step E) does not require the addition of pore-forming materials, such as pore expanders. The pore-forming material refers to the material added during the carrier preparation process. During the molding process, the pore expander molecules are encapsulated by alumina powder particles. After high-temperature calcination, the pore expander molecules are oxidized or undergo other chemical reactions to generate gas and escape, leaving behind the previously occupied space, thus forming large pores. Examples of such materials include carbon black and starch.

[0071] In the method of the present invention, in step E), the shaped product can be a four-leaf clover shape.

[0072] In the method of the present invention, in step E), the drying temperature after molding is 100-180℃, and the drying time is 4-12 hours; the calcination temperature after molding is 500-800℃, and the calcination time is 3-12 hours.

[0073] In the method of this invention, in step F), the impregnation solution containing molybdenum and cobalt contains cobalt at a concentration of 0.7–2.4 g / 100 mL (calculated as cobalt oxide) and molybdenum at a concentration of 3.8–9.6 g / 100 mL (calculated as molybdenum oxide). The molybdenum source can be at least one of ammonium molybdate and molybdenum trioxide. The cobalt source can be at least one of cobalt nitrate and basic cobalt carbonate.

[0074] In the method of the present invention, in step F), the impregnation can be saturated impregnation or supersaturated impregnation, and saturated impregnation is preferred.

[0075] In the method of this invention, in step F), the drying conditions after impregnation are as follows: drying temperature is 100–180°C, and drying time is 4–12 hours; the calcination conditions are as follows: calcination temperature is 450–600°C, and calcination time is 3–6 hours. The calcination atmosphere is an oxygen-containing atmosphere, such as air.

[0076] The hydrodesulfurization catalyst used in this invention can be a conventional residue hydrodesulfurization catalyst. Generally, the hydrodesulfurization catalyst comprises an alumina support and a hydroactive metal component. The hydroactive metal component is preferably a Group VIB or Group VIII metal. Group VIB metals are preferably W and / or Mo. Group VIII metals are preferably Ni and / or Co. Based on the weight of the catalyst, the content of Group VIB metals (calculated as oxides) in the hydrodesulfurization catalyst is 6%-16%, and the content of Group VIII metals (calculated as oxides) is 1.5%-6.0%. The hydrodesulfurization catalyst can be commercially available, such as the FZC series catalysts developed and produced by the Fushun Petrochemical Research Institute of Sinopec.

[0077] In the method of the present invention, the percentage of the loading volume of the hydrogenation protective agent, the hydrogenation transition catalyst, and the hydrogenation desulfurization catalyst to the total loading volume is 3%-30%, 10%-40%, and 30%-87%, respectively.

[0078] In the method of this invention, the basic gradation principle of the hydrogenation protective agent, the hydrogenation transition catalyst, and the hydrogenation desulfurization catalyst can adopt the gradation principle of the residue oil hydrotreating catalyst. For example, along the flow direction, the particle size gradually decreases, the bed porosity gradually decreases, the pore size gradually decreases, and the activity gradually increases. Grading according to this principle can give full play to the optimal activity of the catalyst series.

[0079] In the method of the present invention, the hydrogenation protective agent, the hydrogenation transition catalyst and the hydrogenation desulfurization catalyst need to be sulfided before use. Conventional in-vessel presulfidation or external presulfidation in the art can be adopted.

[0080] In the method of this invention, the catalytic cracking slurry feedstock is one or more of the following: full-fraction slurry, reduced-pressure slurry, and arbitrary-fraction slurry.

[0081] In the method of this invention, the operating conditions for hydrogenation treatment are as follows: reaction temperature 300-400℃, reaction pressure 1.0-10.0 MPa, hydrogen-to-oil volume ratio 200:1-1200:1, and liquid hourly space velocity 0.1-2.0 h⁻¹. -1 .

[0082] In the method of this invention, the hydrogenated oil obtained by hydrogenation treatment has a high content of tricyclic and tetracyclic aromatic hydrocarbons, making it a high-quality raw material for the production of needle coke.

[0083] Compared with the prior art, the present invention has the following beneficial effects:

[0084] 1. In existing technologies, catalytic cracking slurry oil and residue oil are similar, both containing gums and asphaltenes. However, catalytic cracking slurry oil differs from residue oil in properties. Catalytic cracking slurry oil has a lower metal content, and catalyst deactivation is mainly due to coke deposition. The operating cycles of catalytic cracking slurry oil hydrotreating units and residue oil hydrotreating units differ; catalytic cracking slurry oil hydrotreating units typically operate for two years, while residue oil hydrotreating units operate for about one year. Under different feedstock and operating modes, catalytic cracking slurry oil hydrotreating units with a hydrotreating agent possessing as many large pores as possible can accommodate more coke deposits, protect downstream catalysts, extend catalyst lifespan, and ensure long-term operation of the unit. This invention relates to a catalytic slurry hydrotreating method that employs a specific hydrotreating protectant and a hydrotreating transition catalyst graded with conventional hydrodesulfurization catalysts. This eliminates diffusion resistance during the adsorption and reaction of large molecules on the catalyst surface during catalytic cracking slurry hydrotreating, accommodates a greater amount of deposits such as coke, and facilitates long-term operation of the unit. Furthermore, the hydrotreating transition catalyst can perform hydrogenation reactions of small sulfur-containing compounds such as thiols and thioethers, achieving preliminary removal of sulfur impurities from the catalytic cracking slurry. This plays a crucial role in ensuring that the performance of the downstream hydrodesulfurization catalyst is not affected by impurities such as coke deposits. This invention, while comprehensively improving hydrodesulfurization performance, also retains a significant amount of tricyclic and tetracyclic aromatics in the catalytic cracking slurry, providing ideal raw materials for the preparation of high-end carbon-based materials such as needle coke.

[0085] Detailed Implementation Methods

[0086] The technical solution and effects of the present invention will be further illustrated below through embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0087] Unless otherwise specified, the experimental methods used in the following examples are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following examples were purchased from conventional biochemical reagent stores.

[0088] The pore volume and pore size of the alumina support, catalyst, and conventional residue oil hydroprotectant and hydrodemetallization catalyst of the present invention (including embodiments) were all measured by mercury porosimetry using a MicroActive AutoPore V 9600 instrument.

[0089] In this invention, the pore volume and pore size of the alumina supports prepared in Comparative Examples 2 and 3 were determined using a low-temperature liquid nitrogen adsorption method with an ASAP2420 pore structure analyzer from Micron Technology, Inc.

[0090] The specific surface areas of the alumina support and catalyst of the present invention (including the examples) and the alumina support and catalyst prepared in the comparative examples were obtained by low-temperature liquid nitrogen adsorption method using an ASAP2420 pore structure analyzer from Micron Technology, USA.

[0091] Example 1

[0092] Take 100g of alumina trihydrate, 90g of alumina monohydrate, and 10g of sodium aluminate, add 300g of purified water, and grind using a ball mill at 450rpm for 1 hour. The particle size distribution (D50) in the slurry is 7.43μm. Add another 950g of purified water to the ground slurry and stir. Then add 6g of citric acid, 5g of sodium hexametaphosphate, and 10g of Tween-80, bringing the pH of the slurry to 9.03. Transfer the stirred slurry to an autoclave for hydrothermal treatment at 260℃ for 7 hours. Filter and wash the material obtained after hydrothermal treatment, and dry it at 120℃ for 5 hours to obtain alumina dry gel.

[0093] Take 100g of the prepared alumina dry adhesive, add 1g of guar gum powder, 1g of methylcellulose, 0.5g of acetic acid, and 128g of purified water, knead and shape into a four-leaf wheel-shaped carrier. After shaping, dry at 120℃ for 4 hours and calcine at 700℃ for 4 hours to obtain hydrogenation protective agent carrier A;

[0094] An impregnation solution containing molybdenum and cobalt was prepared, wherein the molybdenum source was ammonium molybdate and the cobalt source was cobalt nitrate. The molybdenum content in the impregnation solution, calculated as molybdenum oxide, was 3.16 g / 100 mL, and the cobalt content, calculated as cobalt oxide, was 0.74 g / 100 mL. The hydrogenation protectant carrier A was impregnated with the above-mentioned molybdenum and cobalt-containing impregnation solution using a saturated impregnation method. After impregnation, the carrier was dried at 120°C for 4 hours and calcined at 500°C for 4 hours to obtain the catalytic cracking slurry hydrogenation protectant A of this invention.

[0095] Take 100g of alumina trihydrate, 80g of boehmite, and 5g of sodium aluminate, add 260g of purified water, and grind using a ball mill at 450rpm for 1 hour. The particle size distribution (D50) in the slurry is 6.67μm. Add 1000g of purified water to the ground slurry and stir. Then add 2g of citric acid, 10g of sodium hexametaphosphate, and 10g of silica sol, bringing the pH of the slurry to 9.41. Transfer the stirred slurry to an autoclave for hydrothermal treatment at 230℃ for 5 hours. Filter, wash, and dry the material obtained after hydrothermal treatment at 120℃ for 5 hours to obtain alumina dry gel.

[0096] Take 100g of the prepared alumina dry glue, add 1g of guar gum powder, 1g of methylcellulose, 0.5g of acetic acid and 124g of purified water, mix and knead to form a four-leaf clover-shaped carrier. After forming, dry at 120℃ for 5 hours and calcine at 650℃ for 4 hours to obtain hydrogenation transition catalyst carrier A.

[0097] An impregnation solution containing molybdenum and cobalt was prepared, wherein the molybdenum source was ammonium molybdate and the cobalt source was cobalt nitrate. The molybdenum content in the impregnation solution, calculated as molybdenum oxide, was 8.4 g / 100 mL, and the cobalt content, calculated as cobalt oxide, was 2.0 g / 100 mL. The transition agent carrier A was impregnated with the above-mentioned impregnation solution containing molybdenum and cobalt. After impregnation, the carrier was dried at 120°C for 4 hours and calcined at 500°C for 4 hours to obtain the transition catalyst A for catalytic cracking slurry hydrogenation of the present invention.

[0098] The hydrodesulfurization catalyst used is the FZC-33 catalyst developed and produced by the Fushun Petrochemical Research Institute of Sinopec.

[0099] Catalyst evaluation:

[0100] A fixed-bed reactor was used, with the volume ratios of hydroprotectant, hydrotransfer catalyst, and hydrodesulfurization catalyst being 25%, 35%, and 40%, respectively. The catalyst sulfidation was performed using a wet sulfidation process, employing dimethyl disulfide (DMDS) as the sulfiding agent. The sulfided oil was straight-run diesel, with the sulfiding agent accounting for 1.5% of the straight-run diesel's mass. The sulfidation process involved isothermal sulfidation at 230℃ for 8 hours and then isothermal sulfidation at 320℃ for 8 hours.

[0101] The feedstock oil is a full-fraction slurry with a sulfur content of 1.15 wt% and a density (20℃) of 1.062 g / cm³. 3 The (tri- and tetra-cyclic) aromatic hydrocarbon content was 48.1%. The evaluated process conditions were: reaction pressure 5.0 MPa, reaction temperature 350 °C, hydrogen-to-oil volume ratio 1000, and liquid hourly space velocity 0.8 h⁻¹. -1 The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0102] Example 2

[0103] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrotreating agent. 90 grams of alumina trihydrate, 100 grams of alumina monohydrate, and 10 grams of sodium aluminate were added to 300 grams of purified water and ground using a ball mill. This yielded the hydrotreating agent carrier B and the catalytic cracking slurry hydrotreating agent B of the present invention.

[0104] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrogenation transition catalyst. 80 grams of alumina trihydrate, 100 grams of alumina monohydrate, and 5 grams of sodium aluminate were added to 260 grams of purified water and ground using a ball mill. This yielded the hydrogenation transition catalyst support B and the catalytic cracking slurry hydrogenation transition catalyst B of the present invention.

[0105] Catalyst evaluation:

[0106] Compared with Example 1, hydroprotective agent B and hydrotransition catalyst B were used instead of hydroprotective agent A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0107] Example 3

[0108] Compared to Example 1, the difference lies in that, during the dry gel preparation process of the hydroprotective agent alumina, the stirred slurry is transferred to a high-pressure reactor for hydrothermal treatment at a temperature of 270°C for 6 hours. This yields the hydroprotective agent carrier C and the catalytic cracking slurry hydroprotective agent C of the present invention.

[0109] Compared to Example 1, the difference lies in that, during the dry gel preparation process, the stirred slurry of the hydrogenation transition catalyst is transferred to an autoclave for hydrothermal treatment at a temperature of 270°C for 6 hours. This yields the hydrogenation transition catalyst support C and the catalytic cracking slurry hydrogenation transition catalyst C of the present invention.

[0110] Catalyst evaluation:

[0111] Compared with Example 1, hydroprotectant C and hydrotransition catalyst C were used to replace hydroprotectant A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0112] Example 4

[0113] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrotreating agent. 100g of aluminum hydroxide, 90g of boehmite, and 10g of aluminum sulfate were added to 300g of purified water and ground using a ball mill. Then, 950g of purified water was added to the ground slurry, stirred, and finally 5.5g of sodium hydroxide and 10g of sodium hexametaphosphate were added. The pH of the slurry was 9.21. This yields the hydrotreating agent carrier D and the catalytic cracking slurry hydrotreating agent D of the present invention.

[0114] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrogenation transition catalyst. 100g of commercially available alumina trihydrate, 80g of boehmite, and 5g of aluminum sulfate were added to 260g of purified water and ground using a ball mill. 950g of purified water was then added to the ground slurry, stirred, followed by 6g of sodium hydroxide and 10g of sodium hexametaphosphate. The pH of the slurry was 9.60. This yielded the hydrogenation transition catalyst support D and the catalytic cracking slurry hydrogenation transition catalyst D of the present invention.

[0115] Catalyst evaluation:

[0116] Compared with Example 1, hydroprotectant D and hydrotransition catalyst D were used instead of hydroprotectant A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0117] Example 5

[0118] Compared with Example 1, the difference lies in that 1100 grams of purified water are added to the ground slurry during the preparation of the alumina dry gel used in the hydrotreating agent. This yields the hydrotreating agent carrier E and the catalytic cracking slurry hydrotreating agent E of the present invention.

[0119] Compared with Example 1, the difference lies in that 1100 grams of purified water are added to the ground slurry during the preparation of the alumina dry gel used in the hydrogenation transition catalyst. This yields the hydrogenation transition agent carrier E and the catalytic cracking slurry hydrogenation transition agent E of the present invention.

[0120] Catalyst evaluation:

[0121] Compared to Example 1, hydroprotectant E and hydrotransition catalyst E were used instead of hydroprotectant A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0122] Example 6

[0123] Compared with Example 1, the difference lies in the loading volume ratio of the hydroprotectant, the hydrotransition catalyst, and the hydrodesulfurization catalyst, which are 20%, 35%, and 45%, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0124] Comparative Example 1

[0125] Compared with Example 1, the hydrogenation protective agent, the hydrogenation metal catalyst (replacing the hydrogenation transition catalyst), and the hydrogenation desulfurization catalyst were respectively developed and produced by Sinopec Fushun Petrochemical Research Institute, using FZC-12A, FZC-28, and FZC-33 catalysts, with the loading volume ratios of FZC-12A, FZC-28, and FZC-33 being 25%, 35%, and 40%, respectively.

[0126] The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0127] Comparative Example 2

[0128] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrotreating agent. 100g of aluminum hydroxide and 90g of boehmite were added to 300g of purified water and ground using a ball mill. The solution was then impregnated with active metals, with a molybdenum oxide content of 4.63g / 100mL and a cobalt oxide content of 1.08g / 100mL. This yielded the comparative hydrotreating agent carrier DB and the comparative catalytic cracking slurry hydrotreating agent DB.

[0129] Compared to Example 1, the difference lies in the preparation process of the alumina dry gel used in the hydrotreating transition catalyst. 100g of alumina trihydrate and 80g of boehmite were added to 260g of purified water and ground using a ball mill. When preparing the active metal solution, the molybdenum oxide content was 12.13g / 100mL and the cobalt oxide content was 2.89g / 100mL. Comparative hydrotreating transition catalyst support DB and comparative catalytic cracking slurry hydrotreating transition catalyst DB were obtained.

[0130] Catalyst evaluation:

[0131] Compared with Example 1, hydroprotectant DB and hydrotransition catalyst DB were used to replace hydroprotectant A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0132] Comparative Example 3

[0133] Compared to Example 1, the difference lies in the preparation process of the hydroprotectant. In this example, 950g of purified water was added to the ground slurry and stirred. Then, 7g of sulfuric acid, 5g of sodium hexametaphosphate, and 10g of Tween-80 were added, resulting in a slurry pH of 2.06. The solution was then impregnated with active metals, with a molybdenum oxide content of 7.86g / 100mL and a cobalt oxide content of 1.83g / 100mL. This yielded a comparative hydroprotectant carrier DC and a comparative catalytic cracking slurry hydroprotectant DC.

[0134] Compared with Example 1, the difference lies in the preparation process of the hydrogenation transition catalyst. In this case, 1000g of purified water was added to the ground slurry and stirred. Then, 10g of sodium hydroxide, 10g of sodium hexametaphosphate, and 10g of silica sol were added, resulting in a slurry pH of 13.17. When preparing the active metal solution, the molybdenum oxide content was 20.55g / 100mL, and the cobalt oxide content was 4.89g / 100mL. This yielded the comparative catalytic cracking slurry hydrogenation transition catalyst support DC and the comparative catalytic cracking slurry hydrogenation transition catalyst DC.

[0135] Catalyst evaluation:

[0136] Compared with Example 1, hydroprotectant DC and hydrotransition catalyst DC were used to replace hydroprotectant A and hydrotransition catalyst A, respectively. The results of hydrotreated catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 5 and 6, and the results of hydrotreated catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 7 and 8.

[0137] Table 1. Pore properties and composition of the hydrogenation protective agent carriers obtained in each embodiment.

[0138]

[0139] Note: In the pore distribution of the carriers used in each embodiment, the range from (most probable pore diameter - 30) nm to (most probable pore diameter + 30) nm is a single peak with a peak width of at least 60 nm.

[0140] Table 2. Pore properties and composition of the hydrogenation protective agent supports obtained in each comparative example.

[0141] serial number FZC-12A DB DC carrier properties <![CDATA[Pore volume, cm 3 / g]]> 0.85 0.60 0.42 <![CDATA[Specific surface area, m 2 / g]]> 123 222 246 Most probable aperture, nm 17.5 9 4.5 Aperture concentration range, nm 7～25 4～17.5 - The concentrated pore size occupies the percentage of the total pore volume of the carrier, % 85 76 - Catalyst composition <![CDATA[MoO3,%]]> 3.80 3.75 3.74 CoO, % 0.91(NiO) 0.87 0.87

[0142] Table 3. Properties and catalyst composition of the hydrogenation transition catalyst supports obtained in each example.

[0143] serial number A B C D E carrier properties <![CDATA[Mass percentage of the auxiliary agent SiO2 in alumina, %]]> 2.41 2.39 2.41 2.44 2.40 <![CDATA[Pore volume, cm 3 / g]]> 1.14 1.17 1.21 1.19 1.12 <![CDATA[Specific surface area, m 2 / g]]> 177 173 164 166 181 The percentage of total pore volume in the 10–40 nm range, % 30 27 23 25 33 The percentage of total pore volume in the 150–400 nm range, % 38 40 46 42 35 Catalyst composition <![CDATA[MoO3,%]]> 8.78 8.78 8.79 8.79 8.78 CoO, % 2.09 2.09 2.10 2.09 2.09

[0144] Table 4. Properties and catalyst composition of hydrogenation transition catalyst supports for each comparative example.

[0145]

[0146]

[0147] *Note: The catalyst supports obtained in each comparative example are all single-peaked.

[0148] Table 5 Evaluation results of each embodiment

[0149] serial number Example 1 Example 2 Example 3 Example 4 Example 5 <![CDATA[Hydrogenation product density (20 °C), g / cm 3 > 1.035 1.034 1.031 1.033 1.031 Desulfurization rate, % 74.3 74.5 74.9 74.7 75.3 (Tricyclic + Tetracyclic) Aromatic Retention Rate, % 94.6 94.5 94.2 94.4 94.0

[0150] Table 6 Evaluation results of each pair of proportions

[0151] serial number Comparative Example 1 Comparative Example 2 Comparative Example 3 <![CDATA[Hydrogenation product density (20 °C), g / cm 3 > 1.047 1.043 1.049 Desulfurization rate, % 70.9 72.7 68.6 (Tricyclic + Tetracyclic) Aromatic Retention Rate, % 95.6 95.1 96.2

[0152] Table 7 Evaluation results of each embodiment

[0153] serial number Example 1 Example 2 Example 3 Example 4 Example 5 <![CDATA[Hydrogenation product density (20 °C), g / cm 3 > 1.038 1.037 1.033 1.036 1.034 Desulfurization rate, % 72.0 72.2 72.6 72.4 73.0 (Tricyclic + Tetracyclic) Aromatic Retention Rate, % 94.8 94.7 94.4 94.6 94.2

[0154] Table 8 Evaluation results of each pair of proportions

[0155] serial number Comparative Example 1 Comparative Example 2 Comparative Example 3 <![CDATA[Hydrogenation product density (20 °C), g / cm 3 > 1.051 1.048 1.059 Desulfurization rate, % 67.3 67.5 58.9 (Tricyclic + Tetracyclic) Aromatic Retention Rate, % 95.9 95.6 97.1

[0156] In Table 5-8, the aromatic hydrocarbon retention rate is the percentage of the mass content of tricyclic and tetracyclic aromatic hydrocarbons in the hydrogenation product relative to the mass content of tricyclic and tetracyclic aromatic hydrocarbons in the feedstock. Tricyclic and tetracyclic aromatic hydrocarbons are ideal feedstock aromatic hydrocarbons for preparing high-end carbon-based materials such as needle coke; therefore, the aromatic hydrocarbon retention rate is the ideal aromatic hydrocarbon retention rate.

[0157] As can be seen from Tables 5-8, compared with the comparative agent and conventional hydrogenation series catalysts, the use of the hydrogenation protectant and hydrogenation transition agent of this invention in combination with the conventional hydrogenation desulfurization catalyst gradation results in a slower catalyst system activity decay, better desulfurization activity selectivity and stability, and a greater retention rate for tricyclic and tetracyclic aromatic hydrocarbons.

[0158] The specific embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for hydrotreating catalytic cracking slurry, employing a fixed-bed hydrotreating process, comprising: In the presence of hydrogen, catalytic cracking slurry feedstock is sequentially contacted with a hydrotreating protectant, a hydrotreating transition catalyst, and a hydrodesulfurization catalyst to undergo a hydrotreating reaction, thereby obtaining hydrotreated oil. The hydrogenation protective agent comprises a support and a hydrogenation active metal, wherein an alumina support is used, and the hydrogenation active metal includes molybdenum oxide and cobalt oxide. The alumina support has the following properties: a most probable pore size of 40-100 nm, with channels from (most probable pore size - 30) nm to (most probable pore size + 30) nm accounting for more than 75% of the total pore volume; and the pore volume of the alumina support in the hydrogenation protective agent is 1.00-1.40 cm³. 3 / g, specific surface area is 120~180m² 2 / g; The hydrogenation transition catalyst comprises an alumina support containing promoters, MoO3, and CoO. The support has a bimodal pore size distribution, with smaller pores concentrated in the 10-40 nm range, accounting for 20%-40% of the total pore volume. Larger pores are concentrated in the 150-400 nm range, accounting for 30%-50% of the total pore volume. The pore volume of the support in the hydrogenation transition catalyst is 0.95-1.35 cm³. 3 / g, specific surface area is 110~175m² 2 / g.

2. The method according to claim 1, characterized in that, In the hydrogenation protective agent, the alumina support has the following properties: the most probable pore size is 50~70nm, and the pore volume occupied by channels from (most probable pore size - 30)nm to (most probable pore size + 30)nm accounts for 75%~90% of the total pore volume.

3. The method according to claim 1, characterized in that, Based on the mass of the hydrogenation protectant, the mass content of MoO3 is 2.0%~7.0%, and the mass content of CoO is 0.3%~1.7%. And / or, based on the mass of the hydrogenation transition catalyst, the content of MoO3 is 4.0% to 10.0% and the content of CoO is 0.8% to 2.5%.

4. The method according to claim 1, characterized in that, In the hydrogenation protective agent, the alumina support has a pore volume of 1.10~1.30 cm³. 3 / g, specific surface area is 130~170m² 2 / g; And / or, in the hydrogenation transition catalyst, the pore volume of the support is 1.00~1.25 cm³. 3 / g, specific surface area is 130~170m² 2 / g.

5. The method according to claim 1, characterized in that, The hydrogenation protectant is in the shape of a four-leaf wheel or a four-leaf clover; and / or, the hydrogenation transition catalyst is in the shape of a four-leaf clover.

6. The method according to claim 1, characterized in that, In the hydrogenation transition catalyst, the alumina support containing the auxiliary agent is one or more of fluorine, phosphorus, silicon or boron; the content of the auxiliary agent, calculated by element, accounts for 0.2% to 10% of the total mass of alumina in the support.

7. The method according to claim 6, characterized in that, In the hydrogenation transition catalyst, the alumina support containing the auxiliary agent is silicon; the content of the auxiliary agent, calculated by element, accounts for 1% to 6% of the total mass of alumina in the support.

8. The method according to claim 1, characterized in that, The preparation method of the hydrogenation protective agent includes the following steps: a) The first aluminum source, the second aluminum source and the third aluminum source are mixed with water to obtain a slurry, and then the slurry is ground. b) Add purified water to the slurry obtained in step a) and stir; c) Add modifier, pH adjuster and optional dispersant to the material obtained in step b) to obtain a mixed slurry, and then perform hydrothermal treatment on the mixed slurry; d) The material obtained in step c) is dried to obtain alumina dry adhesive; e) Mix the alumina dry adhesive obtained in step d) with the binder, shape, dry, and calcine to obtain the carrier; f) Impregnate the carrier obtained in step e) with an impregnation solution containing molybdenum and cobalt, and then dry and calcine to obtain the hydrogenation protectant.

9. The method according to claim 8, characterized in that, In step a), the first aluminum source is alumina trihydrate; the second aluminum source is alumina dry gel with a water content of less than 35% by mass fraction; and the third aluminum source is an aluminum-containing salt compound.

10. The method according to claim 9, characterized in that, In step a), the second aluminum source is alumina dry adhesive, which is hydrated alumina; the third aluminum source is at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, and sodium aluminate.

11. The method according to claim 9, characterized in that, In step a), the mass ratio of the first aluminum source, the second aluminum source, and the third aluminum source is 30~66:33~60:1~10.

12. The method according to claim 9, characterized in that, In step a), the amount of water added is 100% to 150% of the total mass of the first aluminum source, the second aluminum source, and the third aluminum source.

13. The method according to claim 9, characterized in that, In step a), the slurry is ground until the particle size in the slurry is 4~20µm, calculated as the median particle size D50.

14. The method according to claim 9, characterized in that, In step b), the slurry obtained in step a) is mixed with purified water so that the total mass of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

15. The method according to claim 8 or 9, characterized in that, In step c), the pH value of the mixed slurry is controlled to be 8.5~12.

0.

16. The method according to claim 15, characterized in that, In step c), the dispersant is a nonionic surfactant with an HLB value of 10-20; and / or, the modifier is at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium ethylenediaminetetraacetate, sodium gluconate, and sodium tartrate.

17. The method according to claim 16, characterized in that, In step c), the dispersant is at least one of Tween-80, lauryl alcohol polyoxyethylene ether, and methyl glucose polyoxyethylene ether.

18. The method according to claim 15, characterized in that, In step c), the amount of the modifier added is 0.01% to 6% of the mass of the material obtained in step b); and / or, the amount of the dispersant added is less than 10% of the mass of the material obtained in step b).

19. The method according to claim 18, characterized in that, In step c), the amount of dispersant added is 0.01% to 10% of the mass of the material obtained in step b).

20. The method according to claim 15, characterized in that, In step c), the hydrothermal treatment conditions are as follows: temperature is 220~280℃, and time is 5~12 hours.

21. The method according to claim 15, characterized in that, In step e), the drying temperature after molding is 100~180℃, and the drying time is 4~12 hours; the calcination temperature after molding is 500~800℃, and the calcination time is 3~12 hours.

22. The method according to claim 1, characterized in that, The preparation method of the hydrogenation transition catalyst includes the following steps: A) The first aluminum source, the second aluminum source, and the third aluminum source are mixed with water to obtain a slurry, and then the slurry is ground. B) Add purified water to the slurry obtained in step A) and stir; C) Add pH adjuster, modifier, auxiliary agent precursor and optional dispersant to the material obtained in step B) to obtain a mixed slurry, and then perform hydrothermal treatment on the mixed slurry; D) The material obtained in step C) is dried to obtain alumina dry adhesive; E) Mix the alumina dry adhesive obtained in step D) with the binder, shape, dry, and calcine to obtain the carrier; F) Impregnate the support obtained in step E) with an impregnation solution containing molybdenum and cobalt, and then dry and calcine to obtain the hydrogenation transition catalyst.

23. The method according to claim 22, characterized in that, In step A), the first aluminum source is alumina trihydrate; the second aluminum source is alumina dry gel with a water content of less than 35% by mass fraction; and the third aluminum source is an aluminum-containing salt compound.

24. The method according to claim 23, characterized in that, In step A), the second aluminum source is hydrated aluminum oxide; the third aluminum source is at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, and sodium aluminate.

25. The method according to claim 23, characterized in that, In step A), the mass ratio of the first aluminum source, the second aluminum source, and the third aluminum source is 30~66:33~60:1~10; and / or, in step A), the amount of water added is 100%~150% of the total mass of the first aluminum source, the second aluminum source, and the third aluminum source.

26. The method according to claim 23, characterized in that, In step A), the slurry is ground until the particle size in the slurry is 4~20µm, calculated as the median particle size D50.

27. The method according to claim 23, characterized in that, In step B), the slurry obtained in step A) is mixed with purified water so that the total mass of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

28. The method according to claim 22 or 23, characterized in that, In step C), the pH value of the mixed slurry in step C) is controlled to be within the range of 9.0 to 12.

5.

29. The method according to claim 28, characterized in that, In step C), the dispersant is a nonionic surfactant with an HLB value of 10-20; the amount of the dispersant added is less than 10% of the mass of the material obtained in step B).

30. The method according to claim 29, characterized in that, In step C), the dispersant is at least one of Tween-80, lauryl alcohol polyoxyethylene ether, and methyl glucose polyoxyethylene ether; the amount of the dispersant added is 0.01% to 10% of the mass of the material obtained in step B).

31. The method according to claim 29, characterized in that, The modifier is at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium ethylenediaminetetraacetate, sodium gluconate, and sodium tartrate; the amount of the modifier added is 0.01% to 10% of the mass of the material obtained in step B).

32. The method according to claim 22, characterized in that, In step C), the additive is one or more of fluorine, phosphorus, silicon or boron; based on the total mass of the first aluminum source, the second aluminum source and the third aluminum source, the amount of additive added as oxide accounts for 0.2% to 10% of the total mass of alumina.

33. The method according to claim 32, characterized in that, In step C), the additive is silicon; based on the total mass of the first aluminum source, the second aluminum source and the third aluminum source, the amount of additive added as oxide accounts for 1% to 6% of the total mass of alumina.

34. The method according to claim 32, characterized in that, In step C), the fluorine precursor is at least one of hydrofluoric acid, ammonium fluoride, boron trifluoride, and sodium fluorosilicate; the phosphorus precursor is at least one of phosphoric acid, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate; the silicon precursor is at least one of silica sol, water glass, and fluorosilicic acid; and the boron precursor is at least one of boric acid, sodium borate, ammonium borate, and ammonium metaborate.

35. The method according to claim 22, characterized in that, In step C), the hydrothermal treatment conditions are as follows: temperature is 200~260℃, hydrothermal time is 4~10 hours; and / or, in step E), the drying temperature after molding is 100~180℃, drying time is 4~12 hours; the calcination temperature after molding is 500~800℃, calcination time is 3~12 hours.

36. The method according to claim 1, characterized in that, The hydrodesulfurization catalyst is a residual oil hydrodesulfurization catalyst.

37. The method according to claim 1, characterized in that, The percentages of the total filling volume of the hydrogenation protective agent, the hydrogenation transition catalyst, and the hydrogenation desulfurization catalyst are 3%-30%, 10%-40%, and 30%-87%, respectively.

38. The method according to claim 1, characterized in that, The feedstock for catalytic cracking slurry oil is one or more of the following: full-fraction slurry oil and reduced-pressure slurry oil.

39. The method according to claim 1, characterized in that, The operating conditions for hydrotreating are as follows: reaction temperature 300-400℃, reaction pressure 1.0-10.0 MPa, hydrogen-to-oil volume ratio 200:1-1200:1, and liquid hourly space velocity (LHSV) 0.1-2.0 h⁻¹. -1 .

Images