Catalytic slurry oil hydrogenation catalyst and preparation method thereof

Abstract

The invention discloses a catalytic slurry oil hydrogenation catalyst and a preparation method thereof. The catalyst comprises an alumina carrier containing an auxiliary agent, MoO3 and CoO, the carrier has bimodal pore size distribution, the smaller pore size is intensively distributed at 10-40nm, the pore volume of pore channels with the pore size of 10-40nm accounts for 20%-40% of the total pore volume, the larger pore size is intensively distributed at 150-400nm, and the pore volume of pore channels with the pore size of 150-400nm accounts for 30%-50% of the total pore volume. The catalyst disclosed by the invention is arranged between a hydrogenation protective agent and a hydrogenation desulfurizing agent in a catalytic cracking oil slurry hydrogenation reactor to play a role of connecting the previous part and the next part, so that primary removal of sulfur impurities in catalytic cracking oil slurry is realized, more deposits such as carbon deposits can be accommodated, and the running period of a device is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogenation, and in particular relates to a catalyst for catalytic oil slurry hydrogenation and a preparation method thereof. Background Art

[0002] As oil resources continue to degrade and become heavier, market demand for diversified and lighter petrochemical products is increasing. Processing low-quality, heavy crude oil has become a critical issue 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. It is also highly adaptable to feedstocks. Currently, some FCC units can directly process atmospheric residue or blend it with vacuum residue, leading to problems such as a poor distribution of FCC products. To increase unit throughput, reduce energy consumption, and increase the production of lighter products, slurry oil disposal is a promising solution. This, in turn, generates a large amount of FCC slurry oil as a byproduct. As a low-value-added product of the FCC process, FCC slurry oil exhibits high density, high carbon residue, high viscosity, and a high aromatic content. It also contains residual catalyst particles and coke, making it challenging to process and utilize. Therefore, how to process and utilize FCC slurry oil has become a critical issue that refineries urgently need to address.

[0003] Catalytic cracking oil, rich in aromatics, is an ideal feedstock for the production of high-end carbon-based materials such as needle coke. Needle coke boasts high crystallinity, high strength, high graphitization, low thermal expansion, and low ablation, making it primarily used in ultra-high power graphite electrodes and lithium-ion battery anode materials. The raw material for needle coke production typically requires FCC oil to have low sulfur, nitrogen, and ash content, and a high aromatics content, particularly high levels of tri- and tetra-ring aromatics.

[0004] FCC slurry 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 is in short supply, while inferior slurry has a high sulfur content (1.0-2.0 wt%). Needle coke products have strict sulfur content requirements (≤ 0.5 wt%). Conventional residue oil hydrogenation catalysts can lead to excessive aromatic losses. Currently, research on hydrogenation catalysts specifically designed for FCC slurry is limited. Therefore, developing catalysts suitable for FCC slurry hydrogenation is of great significance.

[0005] CN103013567A discloses a method for producing needle coke feedstock from catalytic cracking slurry. The method comprises a protection zone and a hydrogenation reaction zone. The protection zone is filled with an adsorbent capable of absorbing catalytic cracking catalyst powder, while the hydrogenation reaction zone is sequentially filled with a hydrogenation protective agent, a hydrogenation demetallization agent, and a hydrogenation desulfurization agent according to the flow direction of the reactants. The catalytic cracking slurry first enters the protection zone to absorb most of the catalytic cracking catalyst powder, then mixes with hydrogen and enters a heating furnace. After heating, it enters the hydrogenation reaction zone for hydrogenation. Among them, the hydrodemetallization agent contains an alumina carrier and molybdenum and / or tungsten, as well as nickel and / or cobalt loaded on the carrier, and the pore distribution of the carrier is such that the pore volume with a pore diameter of 100-200 angstroms (10-20 nm) accounts for 70%-98% of the total pore volume; the hydrodesulfurization agent contains a carrier and molybdenum and / or tungsten, as well as nickel and / or cobalt loaded on the carrier, and the carrier is alumina and optional silica; the pore distribution of the carrier is such that the pore volume with a diameter of 60-100 angstroms (6-10 nm) accounts for 75%-98% of the total pore volume. The above-mentioned hydrodemetallization agents and hydrodesulfurization agents are both conventional residue oil hydrogenation catalysts. Although they can be used for catalytic cracking oil slurry hydrogenation, the metal content and metal deposits of the catalytic cracking oil slurry are relatively low, the pore size of the carrier is relatively small, and the macropore volume is relatively small. During the hydrogenation reaction, the adsorption and reaction of macromolecules such as colloids and asphaltenes in the catalytic cracking oil slurry are affected by diffusion resistance. At the same time, the continuous deposition of carbon deposits during the hydrogenation process can easily cause pore blockage, and the carbon deposits are deposited on the downstream desulfurization catalyst, ultimately leading to plant shutdown.

[0006] Since catalytic cracking slurry oil feedstock is different from conventional residual oil feedstock, conventional residual oil hydrogenation series catalysts in the prior art still have the above-mentioned problems for catalytic cracking slurry oil feedstock. Therefore, it is urgent to develop catalysts suitable for catalytic cracking slurry oil hydrogenation. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention provides a catalytic cracking slurry oil hydrogenation catalyst and its preparation method. The hydrogenation catalyst is installed between the hydrogenation protectant and the hydrodesulfurization agent in the catalytic cracking slurry oil hydrogenation reactor, serving as a link between the two. This catalyst achieves preliminary removal of sulfur impurities in the catalytic cracking slurry oil, while also accommodating more carbon deposits and other sediments, thereby extending the operating cycle of the device.

[0008] Typically, a residue hydrodemetallization catalyst is installed between the hydroprotectant and hydrodesulfurization catalyst in a catalytic cracking slurry hydrogenation reactor. FCC slurry contains relatively few metallic impurities but high levels of colloids and asphaltenes (4.0% to 15.0%). Asphaltene molecules are primarily composed of 5 to 7 flaky, fused aromatic rings measuring 12 to 16 angstroms (1.2 to 1.6 nm), and they are prone to agglomeration. Therefore, conventional hydrodemetallization catalysts are not well suited for FCC slurry hydrogenation. The inventors have discovered through research that by developing a hydrogenation transition agent with a suitable bimodal pore size distribution, the larger pores can effectively eliminate the diffusion resistance of large molecules during adsorption and reaction on the catalyst surface during the hydrogenation of catalytic cracking oil slurry, while accommodating carbon deposits generated during the reaction process and reducing active sites that are inactivated by carbon deposits. The smaller pores are conducive to the hydrogenation reaction of small molecules of sulfur-containing compounds such as mercaptans and sulfides, thereby achieving the initial removal of sulfur impurities in the catalytic cracking oil slurry, and can accommodate more carbon deposits and other sediments, thereby extending the operating cycle of the device.

[0009] The first aspect of the present invention provides a catalytic cracking oil slurry hydrogenation catalyst, wherein the catalyst comprises an alumina carrier containing a promoter and MoO3 and CoO, the carrier having a bimodal pore size distribution, wherein the smaller pore size is concentrated in the range of 10 to 40 nm, and the pore volume of the pores with a pore size of 10 to 40 nm accounts for 20% to 40% of the total pore volume, and the larger pore size is concentrated in the range of 150 to 400 nm, and the pore volume of the pores with a pore size of 150 to 400 nm accounts for 30% to 50% of the total pore volume.

[0010] In the present invention, the pore volume of the carrier is 0.95 to 1.35 cm 3 / g, preferably 1.00 to 1.25 cm 3 / g.

[0011] In the present invention, the specific surface area of ​​the carrier is 110 to 175 m 2 / g, preferably 130 to 170 m 2 / g.

[0012] In the present invention, based on the mass of the hydrogenation catalyst, the content of MoO3 is 4.0% to 10.0%, and the content of CoO is 0.8% to 2.5%.

[0013] In the present invention, in the additive-containing alumina carrier, the additive is preferably one or more of fluorine, phosphorus, silicon or boron, more preferably silicon; the content of the additive as oxide accounts for 0.2% to 10% of the total mass of the alumina in the carrier, preferably 1% to 6%.

[0014] In the present invention, the shape of the catalyst is preferably a four-leaf clover.

[0015] The second aspect of the present invention provides a method for preparing the above catalyst, comprising the following steps:

[0016] a) mixing a first aluminum source, a second aluminum source, and a third aluminum source with water to obtain a slurry, and then grinding the slurry;

[0017] b) adding clean water to the slurry obtained in step a) and stirring;

[0018] c) adding a pH regulator, a modifier, an auxiliary agent precursor, and an optional dispersant to the material obtained in step b) to obtain a mixed slurry, and then subjecting the mixed slurry to a hydrothermal treatment;

[0019] d) drying the material obtained in step c) to obtain alumina dry gel;

[0020] e) mixing the alumina dry glue obtained in step d) with a binder, shaping, drying, and calcining to obtain a carrier;

[0021] f) impregnating the carrier obtained in step e) with an impregnation solution containing molybdenum and cobalt, and obtaining the hydrogenation catalyst through drying and calcining.

[0022] In the method of the present invention, in step a), the first aluminum source is alumina trihydrate.

[0023] In the method of the present invention, in step a), the second aluminum source is alumina gel having a water content of 35% by mass or less. The alumina gel can be a dehydrated alumina hydrate, and can be completely dehydrated alumina or partially dehydrated alumina, such as monohydrated alumina.

[0024] In the method of the present invention, in step a), the third aluminum source is an aluminum-containing salt compound, which can be an acidic aluminum salt, or a basic aluminate and / or metaaluminate. The third aluminum source can be selected from at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, sodium metaaluminate, and the like.

[0025] 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.

[0026] 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.

[0027] In the method of the present invention, in step a), the slurry is ground until the size of the particles in the slurry is 4 to 20 μm, measured by the median particle size D50.

[0028] In the method of the present invention, in step b), the slurry obtained in step a) is added with clean water (preferably deionized water) and stirred so that the total mass content of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

[0029] In the method of the present invention, in step c), the pH regulator can be an alkaline substance (such as at least one of sodium hydroxide, ammonia water, 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 regulator is adjusted according to the properties of the slurry, and the pH value of the mixed slurry in step c) is controlled to be in the range of 9.0 to 12.5.

[0030] In the method of the present invention, in step c), the dispersant is selected from at least one hydrophilic dispersant. The dispersant can be a nonionic surfactant having an HLB value (Hydrophile-Lipophile Balance Number) of 10 to 20. The amount of the 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 ethylenediaminetetraacetic acid, sodium gluconate, sodium tartrate, etc. 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 include but are 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.

[0031] In the method of the present invention, in step c), the auxiliary agent is preferably one or more of fluorine, phosphorus, silicon or boron, more preferably silicon. Based on the total mass of the first aluminum source, the second aluminum source and the third aluminum source, the amount of the auxiliary agent (calculated as oxide) added accounts for 0.2% to 10% of the total mass of the alumina, preferably 1% to 6%. The auxiliary fluorine precursor can be at least one of hydrofluoric acid, ammonium fluoride, boron trifluoride, and sodium fluorosilicate. The auxiliary phosphorus precursor can be at least one of phosphoric acid, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate. The auxiliary silicon precursor can be at least one of silica sol, water glass, and fluorosilicic acid. The auxiliary boron precursor can be at least one of boric acid, sodium borate, ammonium borate, and ammonium metaborate.

[0032] In the method of the present invention, in step c), the conditions of the hydrothermal treatment are as follows: temperature is 200-260° C., and the hydrothermal time is 4-10 hours.

[0033] In the method of the present invention, in step d), before drying, the material obtained in step c) can be filtered, washed, etc. Conventional filtering and washing methods can be used for the filtration and washing.

[0034] In the method of the present invention, in step d), the drying conditions are: drying temperature is 100-180° C., and drying time is 4-12 hours.

[0035] In the method of the present invention, in step e), the binder is selected from at least one of an inorganic acid, an organic acid, cellulose, and a resin. The inorganic acid may be nitric acid, and the organic acid may be selected from at least one of acetic acid, citric acid, and tartaric acid. The cellulose may be at least one of hydroxypropyl cellulose and methyl cellulose, and the resin may be at least one of phenolic resin and ethylene-vinyl acetate resin. The amount of the binder added is 0.1% to 10% of the mass of the dry alumina gel.

[0036] In the method of the present invention, in step e), a molding aid, such as an extrusion aid, may be added depending on the molding conditions. The extrusion aid is selected from sesbania powder and the amount of the extrusion aid added is 0.5% to 6.0% of the mass of the alumina dry glue obtained in step d).

[0037] In the method of the present invention, step e) does not require the addition of pore-forming raw materials, such as pore-enlarging agents. These raw materials, such as carbon black and starch, are added during the carrier preparation process. During the molding process, the pore-enlarging agent molecules are encapsulated by the alumina powder particles. After high-temperature calcination, the pore-enlarging agent molecules are oxidized or undergo other chemical reactions to generate gases that escape, leaving behind the spaces previously occupied, thereby forming large pores.

[0038] In the method of the present invention, in step e), the formed shape may be a four-leaf clover shape.

[0039] In the method of the present invention, in step e), the drying temperature after forming is 100-180° C., and the drying time is 4-12 hours; the roasting temperature after forming is 500-800° C., and the roasting time is 3-12 hours.

[0040] In the method of the present invention, in step f), the impregnation solution containing molybdenum and cobalt has a cobalt content of 0.7 to 2.4 g / 100 mL (calculated as cobalt oxide), and a molybdenum content of 3.8 to 9.6 g / 100 mL (calculated as molybdenum oxide). The molybdenum source may be at least one of ammonium molybdate and molybdenum trioxide. The cobalt source may be at least one of cobalt nitrate and basic cobalt carbonate.

[0041] In the method of the present invention, in step f), the impregnation can be saturated impregnation or supersaturated impregnation, and saturated impregnation is preferably used.

[0042] In the method of the present invention, in step f), the drying conditions after impregnation are as follows: a drying temperature of 100-180°C for a drying time of 4-12 hours; and the calcination conditions are as follows: a calcination temperature of 450-600°C for a calcination time of 3-6 hours. The calcination atmosphere is an oxygen-containing atmosphere, such as air.

[0043] In the present invention, the catalyst is particularly suitable for being loaded between the hydrogenation protectant and the high-selectivity hydrodesulfurization catalyst in the catalytic cracking slurry hydrogenation unit, mainly playing a transitional role between the upper and lower parts, accommodating more carbon deposits and performing a simple desulfurization reaction.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. The present invention provides a catalytic cracking oil slurry hydrogenation catalyst, wherein the carrier used has a bimodal pore size distribution as determined by mercury intrusion testing, wherein the smaller pore size is concentrated in the range of 10 to 40 nm, accounting for 20% to 40% of the total pore volume, and the larger pore size is concentrated in the range of 150 to 400 nm, accounting for 30% to 50% of the total pore volume. Catalytic cracking oil slurry contains relatively low metal content and metal deposits, which, in contrast, requires larger pores to accommodate carbon deposits generated during the reaction. Due to its larger pore size, the carrier used in the present invention can effectively eliminate the diffusion resistance of macromolecules during adsorption and reaction on the catalyst surface during catalytic cracking oil slurry hydrogenation, accommodate more carbon deposits, slow the process of pore blockage, reduce coverage of catalyst active sites by carbon deposits, and reduce the catalyst deactivation rate. Furthermore, the carrier has smaller pores, which facilitates the hydrogenation of small sulfur-containing compounds such as mercaptans and sulfides. The catalyst of the invention plays a transitional role between the upper macroporous hydrogenation protective agent and the lower small-pore high-selectivity hydrogenation desulfurization catalyst in a catalytic cracking oil slurry hydrogenation reaction device.

[0046] 2. The catalyst of the present invention utilizes an alumina support with a bimodal pore size distribution, with Mo as the primary active component and Co as a promoter. The catalyst of the present invention exhibits high desulfurization activity and selectivity. Reactive small molecules such as mercaptans and sulfides preferentially enter the small pores for reaction, resulting in a high degree of retention of tri- and tetra-ring aromatics in the catalytic cracking slurry. The product of hydrogenation of the catalytic cracking slurry is an ideal raw material for the preparation of high-end carbon-based materials such as needle coke. DETAILED DESCRIPTION

[0047] The following examples further illustrate the technical solutions and effects of the present invention. The examples are implemented based on the technical solutions of the present invention, and provide detailed implementation methods and specific operating processes, but the scope of protection of the present invention is not limited to the following examples.

[0048] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, were purchased from conventional biochemical reagent stores.

[0049] The pore volumes and pore diameters of the alumina support components, alumina supports, and catalysts of the present invention (including the embodiments), as well as the alumina support components, alumina supports, and catalysts prepared in Comparative Examples 1, 2, and 4, and conventional residue hydrodemetallization catalyst supports and catalysts, were measured using mercury intrusion porosimetry using a MicroActive AutoPore V 9600 instrument.

[0050] In the present invention, the pore volume and pore diameter of the alumina support component, alumina support and catalyst involved in Comparative Examples 3 and 5 were tested using a low-temperature liquid nitrogen adsorption method using an ASAP2420 pore structure analyzer produced by Micromeritics, USA.

[0051] The specific surface areas of the alumina support components, alumina supports and catalysts in the present invention (including the examples) and the alumina support components, alumina supports and catalysts prepared in the comparative examples were measured using a low-temperature liquid nitrogen adsorption method using a Micromeritics ASAP2420 pore structure analyzer.

[0052] Example 1

[0053] Take 100 grams of alumina trihydrate, 100 grams of pseudo-boehmite and 5 grams of aluminum sulfate, add 250 grams of clean water, use a ball mill to grind, 450 rpm, grind for 1 hour, the particle D50 in the slurry is 6.53 μm. After adding 1100 grams of clean water to the ground slurry and stirring, 5.5 grams of sodium hydroxide, 3 grams of sodium hexametaphosphate, and 12 grams of water glass are added, and the slurry pH value is 9.84. The stirred slurry is transferred to an autoclave for hydrothermal treatment at a temperature of 230°C and a hydrothermal time of 6 hours. The material obtained after hydrothermal treatment is filtered, washed, and dried at 120°C for 5 hours to obtain alumina dry glue GA.

[0054] Take 100 grams of the prepared alumina dry glue, add 2 grams of sesbania powder, 1 gram of methyl cellulose, 0.5 grams of acetic acid, and 125 grams of clean water, and mix and knead to form a four-leaf clover-shaped carrier. After forming, dry it at 120°C for 4 hours and calcine it at 650°C for 4 hours to obtain catalyst carrier A.

[0055] An impregnation solution containing molybdenum and cobalt was prepared, wherein the molybdenum source was ammonium molybdate and the cobalt source was cobalt nitrate. The content of molybdenum in the impregnation solution calculated as molybdenum oxide was 8.4 g / 100 mL, and the content of cobalt in the impregnation solution calculated as cobalt oxide was 2.0 g / 100 mL. A saturated impregnation method was used to impregnate a carrier A with the 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 a catalytic cracking oil slurry hydrogenation catalyst A of the present invention.

[0056] Example 2

[0057] Compared with Example 1, the difference is that during the preparation of the alumina dry gel, 80 grams of alumina trihydrate, 100 grams of pseudo-boehmite, and 5 grams of aluminum sulfate were taken, added with 250 grams of clean water, and ground using a ball mill to obtain the carrier B and catalytic cracking oil slurry hydrogenation catalyst B of the present invention.

[0058] Example 3

[0059] Compared with Example 1, the difference is that during the preparation of the alumina dry gel, 900 g of purified water was added to the ground slurry and stirred, and then 3.0 g of sodium hydroxide, 3 g of sodium hexametaphosphate, and 12 g of water glass were added. The pH value of the slurry was 9.57. Carrier C and catalytic cracking oil slurry hydrogenation catalyst C of the present invention were obtained.

[0060] Example 4

[0061] Compared with Example 1, the difference is that during the preparation of the alumina dry gel, 1100 g of purified water was added to the ground slurry and stirred, and then 5.5 g of sodium hydroxide, 3 g of sodium hexametaphosphate, and 16 g of silica sol were added. The pH value of the slurry was 9.35. This produced the carrier D and catalyst D for catalytic cracking oil slurry hydrogenation of the present invention.

[0062] Example 5

[0063] Compared with Example 1, the difference is that during the preparation of the alumina dry gel, 1100 g of purified water was added to the ground slurry and stirred, and then 5.5 g of sodium hydroxide, 8 g of disodium ethylenediaminetetraacetic acid, and 16 g of silica sol were added. The pH value of the slurry was 9.71. Carrier E and catalyst E for catalytic cracking oil slurry hydrogenation of the present invention were obtained.

[0064] Example 6

[0065] Compared with Example 1, the difference is that during the preparation of the alumina dry gel, the stirred slurry was transferred into an autoclave for hydrothermal treatment at a temperature of 240° C. for 5 hours. Thus, the carrier F and the catalyst F for hydrogenation of catalytic cracking oil slurry of the present invention were obtained.

[0066] Example 7

[0067] Compared with Example 1, the difference is that 5 grams of lauryl alcohol polyoxyethylene ether is added to the ground slurry during the preparation of the alumina dry gel, thereby obtaining the carrier G and the catalyst G for hydrogenation of catalytic cracking oil slurry of the present invention.

[0068] Comparative Example 1

[0069] Compared with Example 1, the difference is that when the alumina dry glue was used for kneading and molding, commercially available macroporous pseudo-boehmite DGA was used. After molding, the mixture was dried at 120°C for 4 hours and calcined at 850°C for 4 hours. The active metal solution was prepared, and the molybdenum oxide content in the solution was 11.44 g / 100 mL and the cobalt oxide content was 2.72 g / 100 mL. A comparative support DA and a comparative catalytic cracking oil slurry hydrogenation catalyst DA were produced.

[0070] Comparative Example 2

[0071] The same as Example 1, except that when preparing the active metal solution, the content of molybdenum oxide in the solution is 8.4 g / 100 mL, and the content of nickel oxide is 2.0 g / 100 mL, to prepare a comparative catalytic cracking oil slurry hydrogenation catalyst DB.

[0072] Comparative Example 3

[0073] Compared to Example 1, the difference is that 100 g of alumina trihydrate and 100 g of pseudo-boehmite were added to 250 g of clean water and ground using a ball mill. When preparing the active metal solution, the molybdenum oxide content in the solution was 12.13 g / 100 mL, and the cobalt oxide content was 2.89 g / 100 mL. This produced a comparative carrier DC and a comparative catalytic cracking oil slurry hydrogenation catalyst DC.

[0074] Comparative Example 4

[0075] Compared to Example 1, the difference was that 1100 g of purified water was added to the ground slurry and stirred, followed by the addition of 5.5 g of sodium hydroxide and 12 g of water glass. When preparing the active metal solution, the molybdenum oxide content in the solution was 11.84 g / 100 mL, and the cobalt oxide content was 2.82 g / 100 mL. A comparative support DD and a comparative catalytic cracking oil slurry hydrogenation catalyst DD were obtained.

[0076] Comparative Example 5

[0077] Compared to Example 1, the difference was that 1100 g of purified water was added to the ground slurry and stirred, followed by the addition of 11 g of sodium hydroxide, 3 g of sodium hexametaphosphate, and 12 g of water glass, resulting in a slurry pH of 13.67. When preparing the active metal solution, the molybdenum oxide content in the solution was 20.55 g / 100 mL, and the cobalt oxide content was 4.89 g / 100 mL. A comparative support DE and a comparative catalytic cracking oil slurry hydrogenation catalyst DE were obtained.

[0078] Table 1, Table 2 and Table 3 list the properties of the supports and catalysts prepared in the above examples and comparative examples, respectively.

[0079] Table 1 Properties of catalyst supports in various examples and comparative examples

[0080]

[0081] Table 2 Properties of the catalyst supports obtained in each comparative example

[0082] Carrier number DA DC DD DE FZC-28 vector <![CDATA[Mass percentage of additive SiO2 in alumina, %]]> 0 2.93 2.87 2.87 - <![CDATA[Pore volume, cm 3 / g]]> 0.80 0.60 0.72 0.38 0.83 <![CDATA[Specific surface area, m 2 / g]]> 154 230 211 330 142 Most probable pore diameter, nm 12.5 9.0 12.5 4.5 17.5 Pore ​​diameter distribution range, nm 5～17.5 4～17.5 7～25 - 7～25 The percentage of concentrated pore size to total pore volume, % 84 76 79 - 82

[0083] *Note: The carriers obtained in each comparative example are all single peaks.

[0084] Table 3 Composition and properties of catalysts in various examples and comparative examples

[0085] Catalyst No. <![CDATA[MoO3,%]]> CoO, % NiO, % <![CDATA[Pore volume, cm 3 / g]]> <![CDATA[Specific surface area, m 2 / g]]> A 8.78 2.09 - 1.07 151 B 8.79 2.09 - 1.10 145 C 8.78 2.09 - 1.02 161 D 8.78 2.09 - 1.05 153 E 8.78 2.09 - 1.03 142 F 8.79 2.10 - 1.13 143 G 8.78 2.09 - 1.08 152 DA 8.78 2.09 - 0.70 134 DB 8.78 - 2.09 1.07 152 DC 8.79 2.09 - 0.51 210 DD 8.79 2.10 - 0.61 190 DE 8.78 2.09 - 0.29 308 FZC-28 8.92 - 2.21 0.68 137

[0086] Catalyst evaluation

[0087] The catalysts prepared in Examples 1-7 and Comparative Examples 1-5 and a conventional residue oil hydrodemetallization agent (brand FZC-28) were taken in equal volumes and respectively loaded between the hydroprotectant and the hydrodesulfurization catalyst in a catalytic cracking slurry hydrogenation reactor. The other catalysts were the same (i.e., the catalysts loaded, from top to bottom, in a volume ratio of 2:2:6, were the hydroprotectant (FZC-12A), the hydrotransition agent of the Examples or Comparative Examples or the conventional hydrodemetallization catalyst (brand FZC-28), and the hydrodesulfurization catalyst (brand FZC-33B)). The catalysts were vulcanized using a wet process, using dimethyl disulfide (DMDS) as the vulcanizing agent, and straight-run diesel fuel, with the vulcanizing agent accounting for 1.5% by weight of the straight-run diesel fuel. The vulcanization process was performed at constant temperatures of 230°C for 8 hours and 320°C for 8 hours. The raw material is full-fraction oil slurry with a sulfur content of 2.15wt% and a density (20℃) of 1.125g / cm 3 The mass content of (three + four ring) aromatics is 52.1%. Process conditions: reaction pressure 6.0 MPa, reaction temperature 340 ° C, hydrogen to oil volume ratio 1000, liquid hourly space velocity 0.5h -1 The results of the hydroprocessed catalytic cracking slurry obtained after 200 hours of operation are listed in Tables 4 and 5, and the results of the hydroprocessed catalytic cracking slurry obtained after 1500 hours of operation are listed in Tables 6 and 7.

[0088] Table 4 Evaluation results of catalysts in various examples

[0089] Catalyst No. A B C D E F G <![CDATA[Density (20 °C) / g·cm -3 > 1.070 1.071 1.067 1.069 1.068 1.072 1.070 Desulfurization rate, % 78.6 78.4 79.0 78.8 78.9 78.2 78.7 Ideal aromatics retention rate, % 87.2 87.4 86.6 87.0 86.8 87.6 87.1

[0090] Table 5 Evaluation results of catalysts in various comparative examples

[0091] Catalyst No. DA DB DC DD DE FZC-28 <![CDATA[Density (20 °C) / g·cm -3 > 1.079 1.075 1.075 1.076 1.086 1.084 Desulfurization rate, % 76.0 76.9 76.9 76.6 73.6 74.3 Ideal aromatics retention rate, % 87.6 84.7 87.1 87.4 88.6 85.3

[0092] Table 6 Evaluation results of catalysts in various examples

[0093] Catalyst No. A B C D E F G <![CDATA[Density (20 °C) / g·cm -3 > 1.073 1.074 1.070 1.072 1.071 1.075 1.073 Desulfurization rate, % 76.3 76.1 76.7 76.5 76.6 75.9 76.4 Ideal aromatics retention rate, % 87.4 87.6 86.8 87.2 87.0 87.8 87.3

[0094] Table 7 Evaluation results of catalysts of various comparative examples

[0095] Catalyst No. DA DB DC DD DE FZC-28 <![CDATA[Density (20 °C) / g·cm -3 > 1.084 1.078 1.081 1.080 1.091 1.087 Desulfurization rate, % 69.4 73.9 71.4 73.2 64.7 68.9 Ideal aromatics retention rate, % 88.0 84.9 87.7 88.2 89.8 85.6

[0096] In Tables 4-7, the aromatics retention rate is the percentage of three- and four-ring aromatics in the hydrogenation product relative to the three- and four-ring aromatics in the feedstock. Three- and four-ring aromatics are ideal feedstock aromatics for producing high-end carbon-based materials such as needle coke, and the aromatics retention rate is the ideal aromatics retention rate.

[0097] It can be seen from Tables 4-7 that, compared with the comparative agent and conventional hydrogenation catalyst, the hydrogenation transition agent prepared using the carrier of the present invention in combination with the original catalyst gradation makes the activity decay of the catalyst system slower, the catalyst system has better desulfurization selectivity and activity stability, and has a greater degree of retention rate for tri-ring and tetra-ring aromatic hydrocarbons.

[0098] The above describes in detail the specific embodiments of the present invention, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as the contents disclosed by the present invention and fall within the scope of protection of the present invention.

Claims

1. A catalytic slurry hydrogenation catalyst, wherein: The catalyst includes an alumina carrier containing an additive and MoO3 and CoO. The carrier has a bimodal pore size distribution, with smaller pore sizes concentrated in the range of 10 to 40 nm, and the pore volume of pores with a pore size of 10 to 40 nm accounting for 20% to 40% of the total pore volume; and larger pore sizes concentrated in the range of 150 to 400 nm, and the pore volume of pores with a pore size of 150 to 400 nm accounting for 30% to 50% of the total pore volume.

2. The catalyst according to claim 1, characterized in that The properties of the carrier include: a pore volume of 0.95 to 1.35 cm 3 / g, preferably 1.00 to 1.25 cm 3 / g; and / or, a specific surface area of ​​110 to 175 m 2 / g, preferably 130 to 170 m 2 / g.

3. The catalyst according to claim 1 or 2, characterized in that Based on the mass of the hydrogenation catalyst, the content of MoO3 is 4.0% to 10.0%, and the content of CoO is 0.8% to 2.5%.

4. The catalyst according to claim 1, characterized in that In the alumina carrier containing an additive, the additive is one or more of fluorine, phosphorus, silicon or boron, preferably silicon; the content of the additive as oxide accounts for 0.2% to 10% of the total mass of the alumina in the carrier, preferably 1% to 6%; And / or, the catalyst is in the shape of a four-leaf clover.

5. A method for preparing the catalyst according to any one of claims 1 to 4, comprising the steps of: a) mixing a first aluminum source, a second aluminum source, and a third aluminum source with water to obtain a slurry, and then grinding the slurry; b) adding clean water to the slurry obtained in step a) and stirring; c) adding a pH regulator, a modifier, an auxiliary agent precursor, and an optional dispersant to the material obtained in step b) to obtain a mixed slurry, and then subjecting the mixed slurry to a hydrothermal treatment; d) drying the material obtained in step c) to obtain alumina dry gel; e) mixing the alumina dry glue obtained in step d) with a binder, shaping, drying, and calcining to obtain a carrier; f) impregnating the carrier obtained in step e) with an impregnation solution containing molybdenum and cobalt, and obtaining the hydrogenation catalyst through drying and calcining.

6. The preparation method according to claim 5, characterized in that In step a), the first aluminum source is alumina trihydrate; the second aluminum source is alumina dry gel, whose water content is less than 35% by mass, preferably alumina monohydrate; the third aluminum source is an aluminum-containing salt compound, preferably selected from at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, and sodium metaaluminate.

7. The preparation method according to claim 5, 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% to 150% of the total mass of the first aluminum source, the second aluminum source and the third aluminum source.

8. The preparation method according to claim 5, characterized in that: In step a), the slurry is ground until the size of the particles in the slurry is 4 to 20 μm, measured by median particle size D50.

9. The preparation method according to claim 5, characterized in that: In step b), clean water is added to the slurry obtained in step a) and stirred, so that the total mass content of the first aluminum source, the second aluminum source and the third aluminum source in the slurry is 10% to 20%.

10. The preparation method according to claim 5, characterized in that: In step c), the pH value of the mixed slurry in step c) is controlled to be in the range of 9.0 to 12.

5.

11. The preparation method according to claim 5, characterized in that: In step c), the dispersant is a nonionic surfactant having an HLB value of 10 to 20, preferably at least one of Tween-80, lauryl alcohol polyoxyethylene ether, and methyl glucose polyoxyethylene ether; the amount of the dispersant added is less than 10% of the mass of the material obtained in step b), preferably 0.01% to 10%.

12. The preparation method according to claim 5, characterized in that: The modifier is at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium ethylenediaminetetraacetic acid, sodium gluconate, and sodium tartrate; and the amount of the modifier added is 0.01% to 10% of the mass of the material obtained in step b).

13. The preparation method according to claim 5, characterized in that: In step c), the auxiliary agent is one or more of fluorine, phosphorus, silicon or boron, preferably silicon; based on the total mass of the first aluminum source, the second aluminum source and the third aluminum source, the amount of the auxiliary agent added as an oxide is 0.2% to 10% of the total mass of alumina, preferably 1% to 6%; preferably, the auxiliary fluorine precursor is at least one of hydrofluoric acid, ammonium fluoride, boron trifluoride, and sodium fluorosilicate, the auxiliary phosphorus precursor is at least one of phosphoric acid, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate, the auxiliary silicon precursor is at least one of silica sol, water glass, and fluorosilicic acid, and the auxiliary boron precursor is at least one of boric acid, sodium borate, ammonium borate, and ammonium metaborate.

14. The preparation method according to claim 5, characterized in that: In step c), the conditions of the hydrothermal treatment are as follows: temperature is 200-260° C., and the hydrothermal time is 4-10 hours.

15. The preparation method according to claim 5, characterized in that: In step d), the drying conditions are: drying temperature is 100-180° C., and drying time is 4-12 hours.

16. The preparation method according to claim 5, characterized in that In step e), the drying temperature after forming is 100-180° C., and the drying time is 4-12 hours; the calcination temperature after forming is 500-800° C., and the calcination time is 3-12 hours.

17. The preparation method according to claim 5, characterized in that In step f), the drying conditions after impregnation are as follows: drying temperature is 100-180° C., and drying time is 4-12 hours; and the roasting conditions are as follows: roasting temperature is 450-600° C., and roasting time is 3-6 hours.

18. Use of the catalyst according to any one of claims 1 to 4 or the catalyst prepared by the method according to any one of claims 5 to 18 in a catalytic cracking slurry oil hydrotreatment process, characterized in that: The catalyst is loaded between the hydrogenation protective agent and the hydrodesulfurization catalyst.

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