Highly active hydrodemetallization catalyst and method for making same

Abstract

The application discloses a high-activity hydrodemetallization catalyst and a preparation method thereof, and belongs to the field of hydrogenation catalysts. The catalyst comprises a modified catalyst body composed of a carrier, an active component modifier and an additive, and has a carbon film layer covering the outer surface of the modified catalyst body. The thickness of the carbon film is 1-300 micrometers. Silicon carbide nanoparticles are dispersed in the carbon film, and the silicon carbide nanoparticles account for 5-15% of the mass of the carbon film. The carbon film layer covers the surface active center, inhibits the violent reaction of residual oil at the active site, effectively prevents the coking, sulfide and metal deposit from blocking the pore and covering the active site, and improves the anti-coking capacity and the stability of the catalyst.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of hydrogenation catalysts, and particularly relates to a high-activity hydrogenation demetallization catalyst and a preparation method thereof. BACKGROUND

[0002] In the field of petroleum and fine chemical industry, hydrogenation demetallization (HDM) technology is widely used in the production of high-quality products and the removal of harmful impurities on catalysts. Fixed-bed residual oil hydrogenation technology is an effective means to realize efficient conversion of heavy oil. However, due to the complexity of residual oil components, it is not only rich in hundreds of ppm of metal impurities, but also contains a large amount of macromolecular substances such as resin and asphaltene. Its hydrogenation reaction is accompanied by multiple irreversible deactivation risks, and it is required to effectively remove metal, sulfur, nitrogen and carbon residue and other impurities in residual oil through catalytic reaction. A single catalyst cannot meet the requirements, and it is necessary to use catalysts with different functions, shapes and sizes to match the loading system to achieve high activity and long-period operation of industrial effect. Residual oil hydrotreating catalysts usually include protective catalysts, demetallization catalysts, desulfurization catalysts and denitrification catalysts, each of which has other functions. The role of hydrogenation demetallization catalyst is to remove Ni, V and other metals in residual oil, and at the same time to protect the desulfurization catalyst. It not only removes metal impurities in the feedstock, but also must accommodate as much metal and coke as possible.

[0003] Fixed-bed residual oil hydrogenation process technology is mature, but due to the reasons of carbon deposition and metal deposition in the catalyst, the operation cycle of fixed-bed residual oil hydrogenation device is greatly shortened (about 12 months), which is much lower than the cycle of upstream and downstream devices such as atmospheric and vacuum distillation, catalytic cracking (2-3 years), forcing the refinery to frequently stop working and replace the catalyst, which seriously restricts the economy and continuity of efficient conversion of heavy and inferior oil. Therefore, the operation cycle of fixed-bed residual oil hydrogenation device has a greater impact on the overall operation and economic benefits of the refinery. Although the traditional hydrogenation demetallization (HDM) catalyst can delay deactivation by optimizing the pore structure of the carrier, it still has significant defects, such as the shrinkage, cracking and even peeling of the thin layer of alumina under high temperature, high pressure and thermal cycling conditions of residual oil hydrogenation, which loses the protection function, leading to a decrease in the activity of the catalyst, and it is difficult to effectively control the reaction intensity of macromolecular substances at the active site.

[0004] Patent CN202111277860.6 discloses a residue hydrotreating catalyst and its preparation method and application. The catalyst includes alumina and hydrogenation metals supported on the alumina. The hydrogenation metals are selected from at least one of group VIB and / or group VIII metals. The catalyst preparation method includes preparing alumina powder, preparing first intermediate, and second intermediate. Finally, the second intermediate, group VIB containing compound, group VIII metal compound, and auxiliary extruding agent are mixed, then molded, dried, and calcined to obtain the catalyst. The catalyst does not construct a physical protective layer to actively shield the pore and surface active center from direct attack by macromolecules and metal deposits. It relies on the double active phase alumina carrier and the active component does not introduce a high thermal stability and high thermal conductivity reinforcing phase. Therefore, when facing high metal content and easy coking residue oil feedstock for a long time, the catalyst's ability to maintain open channels is limited, and it cannot maintain the activity of the catalyst for a long time, making it difficult to meet the stability requirements of the catalyst for long-term operation of the device.

[0005] Therefore, there is an urgent need to develop a catalyst with lower demetallization rate, external surface metal deposition resistance, surface active site stability, and overall stability to meet the long-term needs of the industry. SUMMARY

[0006] To solve the problems of low demetallization rate, insufficient surface active site stability, and insufficient carbon deposition resistance of existing catalysts, the present application provides a high-activity hydrodemetallization catalyst and a preparation method thereof.

[0007] The object of the present application can be achieved by the following technical solutions:

[0008] A high-activity hydrodemetallization catalyst includes a modified catalyst body and a covering layer. The modified catalyst body is composed of a carrier, an active component modifier, and an active component supported on the carrier. The covering layer is a carbon film layer covering the outer surface of the modified catalyst body. The thickness of the carbon film is 1-300 μm. Silicon carbide nanoparticles are dispersed in the carbon film, and the mass of the silicon carbide nanoparticles accounts for 5-15% of the total mass of the carbon film.

[0009] Preferably, the carbon film has a large pore structure with a pore volume of 1.2-1.5 cm 3 / g and an average pore size greater than 50 nm. The particle size of the silicon carbide nanoparticles is 20-100 nm, and the specific surface area is greater than 80 m 2 / g.

[0010] Preferably, a preparation method of a high-activity hydrodemetallization catalyst includes the following steps:

[0011] First, prepare a molybdenum-nickel-phosphorus solution and impregnate

[0012] A 100 mL molybdenum-nickel-phosphorus solution is prepared, wherein the mass of MoO3 is 8-10 g, the mass of NiO is 2-2.6 g, the content of phosphorus is 1-1.4 g, and the rest is deionized water; the active component modifier and the additive are sequentially added to the molybdenum-nickel-phosphorus solution, and stirring is performed at room temperature for 20-40 min to obtain an impregnation solution; the impregnation solution is used to impregnate an alumina carrier, wherein the pore volume of the carrier is 0.9-1.4 cm 3 / g, and the specific surface area is 90-130 m 2 / g, to obtain an impregnated alumina carrier; the impregnated alumina carrier is dried at 105-115 °C for 2-4 h, and then calcined at 520-580 °C for 3-6 h to obtain a modified catalyst body.

[0013] The second step is surface treatment and carbonization.

[0014] The modified catalyst body obtained in the first step is taken out after being soaked in an ammonium bicarbonate solution with a mass percentage of 8-12%, a starch aqueous solution with a mass percentage of 8-15%, and a silicon carbide suspension for 5-20 min, and then the taken-out catalyst is subjected to carbonization treatment to obtain a high-activity hydrodemetallization catalyst.

[0015] Preferably, the active component modifier includes glucose acid with an addition amount of 0.01-0.05 g / mL, ammonium hydrogen phosphate with an addition amount of 0.01-0.03 g / mL, and potassium nitrate with an addition amount of 0.01-0.02 g / mL.

[0016] Preferably, the additive includes one or a combination of several of ethylene glycol, polyethylene glycol, glycerol, xanthan gum, guar gum, and polyvinyl alcohol.

[0017] Preferably, the additive has an addition amount of 0.1-0.4 g / mL.

[0018] Preferably, the preparation method of the silicon carbide suspension includes the following steps:

[0019] The silicon carbide nanoparticles are added to a 45-55 wt% ethanol solution, ultrasonic treatment is performed at 40-60 kHz for 20-40 min, the ultrasonic power is 300-500 W, then sodium polyacrylate and gluconic acid are added, stirring is performed at 40-50 °C for 0.5-1 h, the stirring rate is 300-400 rpm, and standing is performed for 3-5 h to obtain a silicon carbide suspension.

[0020] Preferably, the mass ratio of the silicon carbide nanoparticles, the sodium polyacrylate, and the gluconic acid is 10:0.2-0.4:0.1-0.2.

[0021] Preferably, the carbonization treatment is carried out at 180-250℃ for 4-12h, and then at 350-480℃ for 4-10h under nitrogen atmosphere.

[0022] Advantages of the present application:

[0023] 1. The high-activity hydrogen demetallization catalyst obtained by the present application is coated with a carbon film on the outer surface, and the carbon film covers the active sites on the surface. During the pre-oxidation process, the carboxyl groups in the gluconic acid form a C-O-P bonding network with the phosphate groups generated by the pyrolysis of ammonium hydrogen phosphate, thereby enhancing the carbon film-support interface bonding force and improving the anti-coking performance. In addition, the carboxyl groups (-COOH) and the hydroxyl groups (-OH) chelate Ni 2+ / Mo 6+ , forming a steric hindrance effect to inhibit high-temperature migration. The phosphorus atoms of ammonium hydrogen phosphate form a strong P-O-Mo / Ni chemical bond with the active metals (Mo, Ni), thereby anchoring the metal active sites. The phosphate groups generated by the decomposition of phosphate can preferentially adsorb metal porphyrin compounds, thereby preventing them from contacting the active centers. In the present application, the appropriate amount of potassium nitrate weakens the surface acid strength and acid amount of the catalyst, which is conducive to reducing the amount of coke on the catalyst. In addition, the potassium ions are embedded in the interlayers of the alumina support, which can inhibit the lattice contraction during the phase change process and improve the mechanical stability and anti-coking performance.

[0024] 2. In the present application, the thermal expansion coefficient of silicon carbide (4.5×10 -6 / ℃) is between the carbon layer (1.2×10 -6 / ℃) and the alumina support (8.0×10 -6 / ℃), forming a gradient buffer to avoid cracking of the carbon film at high temperatures. After embedding the carbon film, the surface silicon dioxide and the carbon matrix form Si-O-C covalent bonds after carbonization, which improves the mechanical properties of the carbon film. The thermal conductivity of silicon carbide (120 W / m·K) promotes the diffusion of reaction heat, which can eliminate local overheating and reduce the problem of coke caused by thermal cracking. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0026] In the embodiments, the pore volume of the catalyst is tested by the mercury injection method, and the specific surface area is measured by the nitrogen adsorption / desorption method.

[0027] Embodiment 1: The present embodiment discloses a preparation method of a silicon carbide suspension, comprising the following steps:

[0028] 20g silicon carbide nanoparticles were added to 200mL of 45wt% ethanol solution, ultrasonic for 20min at 40kHz, ultrasonic power was 300W, then 0.4g sodium polyacrylate and 0.2g gluconic acid were added, stirring for 0.5h at 40℃, stirring rate was 300rpm, and standing for 3h, to obtain a silicon carbide suspension.

[0029] The embodiment discloses a preparation method of a high-activity hydrogen demetallization catalyst, comprising the following steps:

[0030] The first step is to prepare a molybdenum-nickel-phosphorus solution and impregnation

[0031] A 100mL molybdenum-nickel-phosphorus solution was prepared, wherein the mass of MoO3 was 8g, the mass of NiO was 2g, the content of phosphorus was 1g, and the rest was deionized water; 1g gluconic acid, 1g ammonium hydrogen phosphate, 1g potassium nitrate and 10g glycerol were sequentially added to the molybdenum-nickel-phosphorus solution, and stirring was conducted at 25℃ for 20min to obtain an impregnation solution; the impregnation solution was used to impregnate 80g of an alumina carrier, the pore volume of the carrier was 0.96cm 3 / g, and the specific surface area was 122m 2 / g, to obtain an impregnated alumina carrier; the impregnated alumina carrier was dried at 105℃ for 2h, and then calcined at 520℃ for 3h to obtain a modified catalyst body;

[0032] The second step is surface treatment and carbonization

[0033] The modified catalyst body obtained in the first step was taken out after being soaked in an ammonium bicarbonate solution with a mass percentage of 8%, a starch aqueous solution with a mass percentage of 8% and a silicon carbide suspension for 5min, and then subjected to carbonization treatment; the taken-out catalyst was pre-oxidized at 180℃ for 4h, and then carbonized at 350℃ for 4h in a nitrogen atmosphere to obtain a high-activity hydrogen demetallization catalyst A1.

[0034] The embodiment discloses a preparation method of a silicon carbide suspension, comprising the following steps:

[0035] 20g silicon carbide nanoparticles were added to 200mL of 55wt% ethanol solution, ultrasonic for 40min at 60kHz, ultrasonic power was 500W, then 0.8g sodium polyacrylate and 0.4g gluconic acid were added, stirring for 1h at 50℃, stirring rate was 400rpm, and standing for 5h, to obtain a silicon carbide suspension.

[0036] The embodiment discloses a preparation method of a high-activity hydrogen demetallization catalyst, comprising the following steps:

[0037] The first step is to prepare a molybdenum-nickel-phosphorus solution and impregnation

[0038] A 100 mL molybdenum-nickel-phosphorus solution is prepared, in which the mass of MoO3 is 10 g, the mass of NiO is 2.6 g, the content of phosphorus is 1.4 g, and the rest is deionized water. Then 5 g of gluconic acid, 3 g of ammonium hydrogen phosphate, and 2 g of potassium nitrate solution and 40 g of glycerol solution are sequentially added to the molybdenum-nickel-phosphorus solution. After stirring at 25°C for 40 min, an impregnation solution is obtained. The impregnation solution is used to impregnate 80 g of an alumina carrier, which has a pore volume of 0.96 cm 3 / g and a specific surface area of 122 m 2 / g. After drying the impregnated alumina carrier at 115°C for 4 h and then calcining it at 580°C for 6 h, a modified catalyst body is obtained.

[0039] Second step, surface treatment and carbonization

[0040] The modified catalyst body obtained in the first step is soaked in a solution containing 12% by mass of ammonium bicarbonate, a 15% by mass starch aqueous solution, and a silicon carbide suspension for 20 min, and then taken out. The taken-out catalyst is then subjected to carbonization treatment. After pre-oxidation at 250°C for 12 h, the catalyst is carbonized at 480°C for 10 h in a nitrogen atmosphere to obtain a high-activity hydrodemetallization catalyst A2.

[0041] Example 3 discloses a preparation method of a silicon carbide suspension, including the following steps:

[0042] 20 g of silicon carbide nanoparticles are added to 200 mL of a 50 wt% ethanol solution, and ultrasonic treatment is performed at 50 kHz for 30 min at a power of 400 W. Then, 0.6 g of sodium polyacrylate and 0.3 g of gluconic acid are added, and stirring is performed at 45°C for 0.8 h at a stirring rate of 350 rpm. After standing for 4 h, a silicon carbide suspension is obtained.

[0043] Example 4 discloses a preparation method of a high-activity hydrodemetallization catalyst, including the following steps:

[0044] First step, preparation of a molybdenum-nickel-phosphorus solution and impregnation

[0045] A 100 mL molybdenum-nickel-phosphorus solution is prepared, in which the mass of MoO3 is 9 g, the mass of NiO is 2.4 g, the content of phosphorus is 1.2 g, and the rest is deionized water. Then 3.2 g of gluconic acid, 2.4 g of ammonium hydrogen phosphate, 1.5 g of potassium nitrate, and 20 g of glycerol are sequentially added to the molybdenum-nickel-phosphorus solution. After stirring at 25°C for 30 min, an impregnation solution is obtained. The impregnation solution is used to impregnate an alumina carrier, which has a pore volume of 0.96 cm / g and a specific surface area of 122 m

[0046] / g, and the impregnated alumina carrier was dried at 110°C for 3h, and then calcined at 560°C for 5h to obtain the modified catalyst body;

[0046] Second step, surface treatment and carbonization

[0047] The modified catalyst body obtained in the first step was immersed in a solution containing 10% by mass of ammonium bicarbonate, a 10% by mass aqueous starch solution, and a silicon carbide suspension for 15 min, and then taken out. The taken-out catalyst was then subjected to carbonization treatment, pre-oxidized at 200°C for 8h, and then carbonized at 400°C for 8h in a nitrogen atmosphere to obtain a high-activity hydrodemetallization catalyst A3.

[0048] Comparative Example 1

[0049] The same as in Example 3, except that no glycerol was added to the molybdenum-nickel-phosphorus solution, to obtain a high-activity hydrodemetallization catalyst B.

[0050] Comparative Example 2: This comparative example discloses a method for preparing a high-activity hydrodemetallization catalyst, comprising the following steps:

[0051] First step, preparation of a molybdenum-nickel-phosphorus solution and impregnation

[0052] A 100 mL molybdenum-nickel-phosphorus solution was prepared, in which the mass of MoO3 was 9g, the mass of NiO was 2.4g, the content of phosphorus was 1.2g, and the rest was deionized water. 3.2g of gluconic acid, 2.4g of ammonium hydrogen phosphate, and 20g of glycerol were sequentially added to the molybdenum-nickel-phosphorus solution, and stirred at 25°C for 30 min to obtain an impregnation solution. The impregnation solution was used to impregnate an alumina carrier, the pore volume of the carrier was 0.96cm 3 / g, and the specific surface area was 122m 2 / g, and the impregnated alumina carrier was dried at 110°C for 3h, and then calcined at 560°C for 5h to obtain the catalyst body.

[0053] Second step, the impregnated alumina carrier was dried at 110°C for 3h, and then calcined at 560°C for 5h to obtain the catalyst body.

[0054] Second step, preparation of a molybdenum-nickel-phosphorus solution and impregnation

[0055] A 100 mL molybdenum-nickel-phosphorus solution was prepared, in which the mass of MoO3 was 9g, the mass of NiO was 2.4g, the content of phosphorus was 1.2g, and the rest was deionized water. 3.2g of gluconic acid, 2.4g of ammonium hydrogen phosphate, and 20g of glycerol were sequentially added to the molybdenum-nickel-phosphorus solution, and stirred at 25°C for 30 min to obtain an impregnation solution. The impregnation solution was used to impregnate an alumina carrier, the pore volume of the carrier was 0.96cm 3 / g, and the specific surface area was 122 m 2 / g, and the specific surface area was 122 m 2 / g, and the specific surface area was 122 m

[0056] Second step, surface treatment and carbonization

[0057] The modified catalyst body obtained in the first step was taken out after being soaked in a solution containing 10% by mass of ammonium bicarbonate and 10% by mass of starch aqueous solution for 15 min, and then the taken-out catalyst was subjected to carbonization treatment, pre-oxidized at 200°C for 8 h, and then carbonized at 400°C for 8 h under a nitrogen atmosphere to obtain a high-activity hydrodemetallization catalyst D.

[0058] Comparative Example 4

[0059] First step, preparation of molybdenum-nickel-phosphorus solution and impregnation

[0060] A molybdenum-nickel-phosphorus solution of 100 mL was prepared, in which the mass of MoO3 was 9 g, the mass of NiO was 2.4 g, the content of phosphorus was 1.2 g, and the rest was deionized water. Then 3.2 g of gluconic acid, 2.4 g of ammonium hydrogen phosphate, 1.5 g of potassium nitrate, and 20 g of glycerol were sequentially added to the molybdenum-nickel-phosphorus solution, and stirred at 25°C for 30 min to obtain an impregnation solution. The impregnation solution was used to impregnate an alumina carrier, and the pore volume of the carrier was 0.96 cm 3 / g, and the specific surface area was 122 m 2 / g, and the specific surface area was 122 m

[0061] Second step, surface treatment and carbonization

[0062] The modified catalyst body obtained in the first step was taken out after being soaked in a solution containing 10% by mass of ammonium bicarbonate and 10% by mass of starch aqueous solution for 15 min, and then the taken-out catalyst was subjected to carbonization treatment, pre-oxidized at 200°C for 8 h, and then carbonized at 400°C for 8 h under a nitrogen atmosphere to obtain a high-activity hydrodemetallization catalyst D.

[0063] Comparative Example 5

[0064] A 100 mL molybdenum-nickel-phosphorus solution was prepared, in which the mass of MoO3 was 9 g, the mass of NiO was 2.4 g, the content of phosphorus was 1.2 g, and the rest was deionized water. 20 g of glycerol was added to the molybdenum-nickel-phosphorus solution, and stirring was performed at 25 °C for 30 min to obtain an impregnation solution. The impregnation solution was used to impregnate an alumina carrier, in which the pore volume was 0.96 cm 3 / g, and the specific surface area was 122 m 2 / g, to obtain an impregnated alumina carrier. The impregnated alumina carrier was dried at 110 °C for 3 h, and then calcined at 560 °C for 5 h to obtain a high-activity hydrodemetallization catalyst F.

[0065] The physicochemical properties of the high-activity hydrodemetallization catalyst are shown in Table 1:

[0066] Table 1

[0067]

[0068] The properties of the raw oil are shown in Table 2:

[0069] Table 2

[0070]

[0071] The experimental process conditions are shown in Table 3:

[0072] Table 3

[0073]

[0074] The content of each impurity in the product oil was determined on a fixed-bed hydrogenation test device according to the following method, and the metal removal rate was calculated. The demetallization rate (HDM, %) = (content of metal (Ni + V) in the raw oil - content of metal (Ni + V) in the product) / content of metal (Ni + V) in the raw oil × 100%. The demetallization rate of the high-activity hydrodemetallization catalyst was calculated, and the results of the demetallization rate (%) are shown in Table 4:

[0075] Table 4

[0076]

[0077] As can be seen from Table 4, compared with the comparative examples 1-5, the high-activity hydrodemetallization catalyst prepared in the examples 1-3 has better demetallization performance and good stability, and can maintain high activity for a long time.

[0078] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is not intended to exclude myriad other embodiments of the present application that other inventors can develop based on the same general inventive concepts embodied by the described embodiments. That is, although the present application is described in terms of particular embodiments and illustrative figures, it should be apparent that the scope of the present application is not limited to these specific embodiments.

[0079] While the embodiments of the application have been shown and described herein, it will be understood by those skilled in the art that many changes, modifications, substitutions and alterations to these embodiments can be made without departing from the principles and spirits of the application, and it is intended that the scope of the application be limited solely by the scope of the appended claims and the equivalents thereof.

Claims

1. A highly active hydrogenation demetallization catalyst, characterized in that, The catalyst comprises a modified catalyst body and a capping layer. The modified catalyst body consists of a support, an active modifier, and an active component supported on the support. The capping layer is a carbon film covering the outer surface of the modified catalyst body, the carbon film having a thickness of 1-300 μm. Silicon carbide nanoparticles are dispersed in the carbon film, and the mass of the silicon carbide nanoparticles accounts for 5-15% of the total mass of the carbon film. The carbon film has a macroporous structure with a pore volume of 1.2-1.5 cm. 3 / g, with an average pore size greater than 50nm; the silicon carbide nanoparticles have a particle size of 20-100nm and a specific surface area greater than 80m². 2 / g; The modified catalyst body is prepared as follows: A 100 mL molybdenum-nickel-phosphorus solution is prepared, wherein the mass of MoO3 is 8-10 g, the mass of NiO is 2-2.6 g, the phosphorus content is 1-1.4 g, and the remainder is deionized water. The active component modifier and additives are added sequentially to the molybdenum-nickel-phosphorus solution, and the mixture is stirred at room temperature for 20-40 min to obtain an impregnation solution. This impregnation solution is then used to impregnate an alumina support with a pore volume of 0.9-1.4 cm³. 3 / g, specific surface area is 90-130m² 2 / g, to obtain the impregnated alumina support, the impregnated alumina support is dried at 105-115℃ for 2-4h, and then calcined at 520-580℃ for 3-6h to obtain the modified catalyst body.

2. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 1, characterized in that, Includes the following steps: Step 1: Preparation of molybdenum-nickel-phosphorus solution and impregnation Prepare a 100 mL molybdenum-nickel-phosphorus solution, comprising 8-10 g MoO3, 2-2.6 g NiO, 1-1.4 g phosphorus, and the remainder deionized water. Add the active component modifier and additives sequentially to the molybdenum-nickel-phosphorus solution and stir at room temperature for 20-40 min to obtain an impregnation solution. Impregnate an alumina support with a pore volume of 0.9-1.4 cm³. 3 / g, specific surface area is 90-130m² 2 / g, to obtain the impregnated alumina support, the impregnated alumina support is dried at 105-115℃ for 2-4h, and then calcined at 520-580℃ for 3-6h to obtain the modified catalyst body. Step 2: Surface treatment and carbonization The modified catalyst obtained in the first step is immersed in a solution containing 8-12% ammonium bicarbonate, 8-15% starch aqueous solution, and silicon carbide suspension for 5-20 minutes, and then removed. The removed catalyst is then subjected to carbonization treatment to obtain a highly active hydrogenation demetallization catalyst.

3. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The active component modifier includes gluconic acid at an addition amount of 0.01-0.05 g / mL, ammonium hydrogen phosphate at an addition amount of 0.01-0.03 g / mL, and potassium nitrate at an addition amount of 0.01-0.02 g / mL.

4. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The additives include one or a combination of several of the following: ethylene glycol, polyethylene glycol, glycerol, xanthan gum, guar gum, and polyvinyl alcohol.

5. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The amount of the additive added is 0.1-0.4 g / mL.

6. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The method for preparing the silicon carbide suspension includes the following steps: Silicon carbide nanoparticles were added to a 45-55 wt% ethanol solution and sonicated at 40-60 kHz for 20-40 min with an ultrasonic power of 300-500 W. Then, sodium polyacrylate and gluconic acid were added and stirred at 40-50 °C for 0.5-1 h with a stirring rate of 300-400 rpm. The mixture was then allowed to stand for 3-5 h to obtain a silicon carbide suspension.

7. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The mass ratio of silicon carbide nanoparticles, sodium polyacrylate, and gluconic acid is 10:0.2-0.4:0.1-0.

2.

8. The method for preparing a highly active hydrogenation demetallization catalyst according to claim 2, characterized in that, The carbonization treatment conditions are: pre-oxidation at 180-250℃ for 4-12 hours, followed by carbonization at 350-480℃ for 4-10 hours under a nitrogen atmosphere.

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