Preparation method of oil slurry selective hydrogenation catalyst

Abstract

The invention discloses a preparation method of an oil slurry selective hydrogenation catalyst, which comprises the following steps: (1) impregnating a hydrogenation catalyst carrier by using an impregnation liquid containing Mo and Co, drying and roasting the impregnated carrier, and vulcanizing; and (2) carrying out saturated impregnation on the catalyst vulcanized in the step (1) by using liquid olefin, and then carrying out closed heat treatment under the condition of a CO2 atmosphere with a certain concentration to obtain the oil slurry selective hydrogenation catalyst. According to the method, the direct desulfurization activity is enhanced, the saturation performance of tricyclic and tetracyclic aromatic hydrocarbons is weakened, and the prepared catalyst is suitable for catalyzing the selective hydrodesulfurization reaction of slurry oil.

Description

Technical Field

[0001] This invention relates to a method for preparing an oil slurry hydrogenation catalyst, and particularly to a method for preparing an oil slurry selective hydrogenation catalyst for producing needle coke feedstock. Background Technology

[0002] Needle coke, used as a raw material for graphite electrodes, must have a low sulfur content. Based on the properties and formation mechanism of needle coke, raw materials with low sulfur content and high content of tricyclic and tetracyclic aromatic hydrocarbons should be selected. Although catalytic slurry has a high content of polycyclic aromatic hydrocarbons, it still requires hydrodesulfurization treatment due to its typically high sulfur content.

[0003] The production of needle coke feedstock through catalytic slurry hydrotreating requires achieving high desulfurization activity while minimizing the hydrosaturation activity of tricyclic and tetracyclic aromatics. Sulfur in catalytic slurry is mainly distributed in polycyclic aromatic hydrocarbons, gums, and asphaltenes. The presence of these complex compounds makes hydrodesulfurization reactions significantly more difficult than those of distillate oils with relatively lower molecular weights. The complex macromolecular structure of catalytic slurry easily creates steric hindrance, hindering the adsorption of sulfur atoms by the active sites of the catalyst. The feedstock contains a significant amount of coking precursors, which easily form coke deposits on the catalyst surface during the reaction, leading to a decrease in catalyst activity. The adsorption and deposition of macromolecules on the catalyst surface also increases diffusion resistance within the reaction. Furthermore, achieving desulfurization activity while maintaining the lowest possible saturation of tricyclic and tetracyclic aromatics is crucial. The large molecular weight, complex structure, and high aromatic content of catalytic slurry further complicate the hydrotreating process for needle coke production.

[0004] CN113862035A discloses a method for producing high-end needle coke feedstock from catalytic cracking slurry. The reaction stream first enters the desulfurization catalyst unit in the hydrotreating reactor, and then enters the hydrotreating aromatization repair catalyst unit. The hydrotreating desulfurization catalyst is a hydrotreating desulfurization catalyst with γ-Al2O3 as support and molybdenum and nickel as active components. Aromatics need to be restored to meet the requirements for producing high-end needle coke components.

[0005] CN110628461A discloses a method for selective hydrodesulfurization of oil slurry while retaining aromatics. First, ultrasonic-assisted centrifugation is used to remove catalyst particles from the middle layer of the oil slurry. The mechanical action of ultrasound can effectively improve the removal effect of catalyst particles. Then, the residual catalyst particles, asphaltenes, and gums in the oil slurry are removed, while the extracted oil enriched with aromatics is retained. Then, the extracted oil is selectively hydrodesulfurized using an Fe-modified CoMo / γAl2O3 selective hydrodesulfurization catalyst. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing a selective hydrodesulfurization catalyst for oil slurry. This method enhances the direct desulfurization activity and weakens the saturation properties of tricyclic and tetracyclic aromatic hydrocarbons, resulting in a catalyst suitable for catalyzing selective hydrodesulfurization reactions in oil slurry.

[0007] The method for preparing the oil slurry selective hydrogenation catalyst of the present invention includes the following steps: (1) The hydrogenation catalyst support is impregnated with an impregnation solution containing Mo and Co. After impregnation, the support is dried, calcined, and then subjected to sulfidation treatment. (2) After step (1), the catalyst is saturated with liquid olefins and then subjected to closed heat treatment under a certain concentration of CO2 atmosphere to obtain the oil slurry selective hydrogenation catalyst.

[0008] In the method of this invention, the preparation of the impregnation solution is well known to those skilled in the art. Generally, a compound containing an active metal element is used as the source, and the concentration and amount of the impregnation solution are determined according to the catalyst composition. Generally, Mo is molybdenum trioxide, and Co is basic cobalt carbonate; the impregnation method generally employs a saturated spray impregnation method to load the active component.

[0009] In the method of the present invention, the drying conditions in step (1) are: drying at 100~120℃ for 1~5 hours, and the calcination conditions are: calcination at 400~550℃ for 1~5 hours.

[0010] In the method of this invention, the sulfidation treatment in step (1) is carried out by an in-vessel or out-of-vessel sulfidation process. The amount of sulfiding agent introduced is 90% to 150% of the theoretical sulfur required by the catalyst. The sulfidation process adopts a programmed temperature rise, and the temperature is raised to 200 to 350°C and held at that temperature for 1 to 16 hours. The sulfiding agent is generally one or more of carbon disulfide, dimethyl disulfide, methyl sulfide, and n-butyl sulfide.

[0011] In the method of the present invention, the liquid olefin in step (2) is one or more of olefins and dienes with 2 to 10 carbon atoms, preferably hexadiene and / or n-heptene.

[0012] In the method of this invention, the closed heat treatment process in step (2) is as follows: heating at 300~400℃ for 1~72h in a closed container; more preferably, heating at 50~250℃ for 1~8h, raising the temperature to 250~300℃ for 1~72h, and then raising the temperature to 300~400℃ for 1~72h. The closed container can be selected according to the reaction conditions and the properties of the materials, such as a reaction vessel, a tube furnace, etc.

[0013] In the method of the present invention, the CO2 concentration in step (2) is ≥3000μg / g, preferably ≥6000μg / g.

[0014] The selective hydrogenation catalyst for oil slurry of the present invention comprises active metals Mo and Co, and a support γ-Al₂O₃. By total weight of the catalyst, MoS₂ comprises 10 wt% to 52 wt%, preferably 16 wt% to 39 wt%, and Co₉S₈ comprises 2 wt% to 13%, preferably 4 wt% to 11 wt%. The carbon content, by elemental weight, is 0.5% to 18.0%, preferably 5% to 18.0%, with the support content as the balance. The γ-Al₂O₃ has an average pore size of 8.0 to 12.0 nm, preferably 8.5 to 11.5 nm, and a specific surface area of ​​270 to 330 m². 2 ·g -1 Preferred size: 280~320m 2 ·g -1 The pore volume is 0.66~0.99cm. 3 ·g -1 The preferred diameter is 0.68~0.80cm. 3 ·g -1 The total amount of pyridine-infrared acid is 0.4~0.7 mmol·g. -1 The preferred dosage is 0.45~0.65 mmol·g. -1 The amount of Brønsted acid is 0.13~0.20 mmol·g. -1 The preferred dosage is 0.15~0.18 mmol·g. -1 The acid content of L-acid is 0.20~0.57 mmol·g. -1 The preferred dosage is 0.27~0.50 mmol·g. -1 The ratio of Brønsted acid to Lourdesic acid is 0.30 to 1.00, preferably 0.35 to 0.66.

[0015] The application of the slurry selective hydrogenation catalyst of the present invention in the slurry selective hydrogenation process generally follows these process conditions: pressure 4.0~6.0 MPa, space velocity 0.5~1.0 h⁻¹. -1 The temperature is 300~390℃, and the hydrogen-to-oil volume ratio is 100~800, making it particularly suitable for the selective hydrogenation of oil slurry to prepare needle coke feedstock. The catalyst of this invention is also applicable to the hydrodesulfurization process of gasoline, kerosene, diesel, and wax oil fractions.

[0016] In selective hydrogenation of slurry oil, balancing the hydrogenation desulfurization performance of the catalyst with the inhibition of hydrogenation saturation of tricyclic and tetracyclic aromatic hydrocarbons has always been a difficult challenge. The molecular diameters of 4,6-dimethyldibenzothiophene and 2,4,8-trimethyldibenzothiophene, which are difficult to remove sulfur-containing compounds, are 0.88 nm and 0.98 nm, respectively, while the macromolecular diameter of tricyclic and tetracyclic aromatic hydrocarbons is around 1.15 nm. This invention utilizes γ-Al₂O₃ with suitable pore size, specific surface area, pore volume, and acidity. The average pore size of γ-Al₂O₃ is close to 10 times the macromolecular diameter of both the large sulfur-containing compounds and the tricyclic and tetracyclic aromatic hydrocarbons, allowing the macromolecules to diffuse within the Knudsen diffusion process. The average pore size of γ-Al₂O₃ is also greater than 10 times the diameter of the large sulfur-containing compounds, thus reducing the sulfur content of the macromolecules. The collisions between the reactants and the catalyst pore walls are more frequent than the collisions between molecules, increasing the contact frequency between the reactant molecules and the active centers, which is beneficial to the desulfurization reaction. However, the average pore size of γ-Al2O3 is less than 10 times the diameter of the macromolecules of tricyclic and tetracyclic aromatic hydrocarbons. The confinement effect of the pores makes the collisions between tricyclic and tetracyclic aromatic hydrocarbon molecules more frequent than the collisions between molecules and the catalyst pore walls, which is not conducive to contact with the active centers and reduces the saturation of tricyclic and tetracyclic aromatic hydrocarbons. A higher Brønsted acid / Low acid ratio means a reduction in L acid in the support, which is beneficial to improving the catalyst's resistance to coking, while an increase in Brønsted acid is beneficial to improving the hydrodesulfurization activity of the catalyst. The inventors ingeniously utilized the different active sites on the catalyst in the hydrodesulfurization reaction and the hydrogenation saturation reaction of tricyclic and tetracyclic aromatic hydrocarbons. A large amount of acidic CO2 molecules were adsorbed onto the active sites of the hydrodesulfurization reaction, followed by saturation impregnation with liquid olefins and then heat treatment to form coke. Due to the protective effect of CO2 molecules on the active sites of the hydrodesulfurization reaction, the coke mainly covered the active sites of the tricyclic and tetracyclic aromatic hydrocarbon hydrogenation saturation reaction, inhibiting the saturation activity of the tricyclic and tetracyclic aromatic hydrocarbons. Because the coke mainly covered the active sites of the tricyclic and tetracyclic aromatic hydrocarbon hydrogenation saturation reaction, while the coke on the active sites of the hydrodesulfurization reaction protected by CO2 molecule adsorption was not significant, the hydrodesulfurization activity and selectivity of the catalyst were increased. Combined with the suitable pore size of γ-Al2O3, selective hydrogenation of the oil slurry was achieved. Detailed Implementation

[0017] In this invention, the specific surface area and pore volume are determined by low-temperature liquid nitrogen adsorption method.

[0018] The specific preparation process of the catalyst of this invention is as follows: The carrier is placed in a rotating pot. A Mo / Co solution, saturated with the carrier's water absorption capacity, is sprayed into the pot via atomization. After spraying, the pot continues to rotate for 10-60 minutes, then left to stand for 1-24 hours. It is then dried at 100-120℃ for 1-5 hours, followed by calcination at 400-550℃ for 1-5 hours at a rate of 150-250℃ / hour. Sulfurization is then performed using an in-vessel or external sulfidation process, introducing 90%-150% of the theoretical sulfur requirement of the catalyst. The sulfidation process uses a programmed temperature rise, maintaining a constant temperature of 200-350℃ for 1-16 hours. CO2 with a concentration of ≥3000 μg / g is introduced into a closed system, followed by saturated impregnation with liquid olefins and heat treatment at 300-400℃ for 1-72 hours to obtain the finished catalyst. Example 1

[0019] 100g of alumina support A (water absorption rate 90mL / 100g) was placed in a boiling pot. Under rotating conditions, 90mL of an impregnation solution containing 27.5g of molybdenum trioxide and 22.7g of basic cobalt carbonate was sprayed onto the alumina support in the boiling pot via atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours. It was then dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours with a heating rate of 200℃ / hour. Sulfidation was performed using an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, reaching 320℃ and holding at that temperature for 10 hours, and then maintaining the CO2 content at 6900μg / g. Under certain atmospheric conditions, the catalyst was immersed in 600 mL of hexadiene solvent for 4 hours, then heated at 200°C for 4 hours, then heated at 300°C for 24 hours, and then heated at 400°C for 10 hours for heat treatment to obtain the finished catalyst A. Example 2

[0020] 100g of alumina support B (water absorption rate 90mL / 100g) was placed in a boiling pot. Under rotating conditions, 90mL of an impregnation solution containing 29.0g of molybdenum trioxide and 17.9g of basic cobalt carbonate was sprayed into the alumina support in the boiling pot in a mist manner. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours, dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours at a heating rate of 200℃ / hour. Sulfidation was carried out using an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, and the temperature was kept constant at 320℃ for 10 hours. Then, under an atmosphere where the CO2 content was always maintained at 4700μg / g, the catalyst was impregnated in 600mL of hexadiene solvent for 4 hours, and then heat-treated at 400℃ for 10 hours to obtain the finished catalyst B. Example 3

[0021] 100g of alumina carrier C (water absorption rate 90mL / 100g) was placed in a boiling pan. While rotating, 90mL of an impregnation solution containing 25.0g of molybdenum trioxide and 16.3g of basic cobalt carbonate was sprayed onto the alumina carrier in the pan via atomization. After spraying, the pan was rotated for another 30 minutes, then left to stand for 18 hours. It was then dried at 110℃ for 3 hours, and finally calcined at 500℃ for 3 hours with a heating rate of 200℃ / hour. The sulfidation process involves introducing dimethyl disulfide at 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employs programmed temperature increase, with the temperature raised to 320℃ and held constant for 10 hours. Then, the CO2 content is maintained at 5800 μg / g in the atmosphere, and the catalyst is immersed in 600 mL of hexadiene solvent for 4 hours. It is then heated at 200℃ for 4 hours, raised to 300℃ for 24 hours, and then heated to 400℃ for 10 hours for heat treatment to obtain the finished catalyst C. Example 4

[0022] 100g of alumina support D (water absorption rate 90mL / 100g) was placed in a boiling pot. Under rotating conditions, 90mL of an impregnation solution containing 28.6g of molybdenum trioxide and 16.8g of basic cobalt carbonate was sprayed into the alumina support in the boiling pot in a mist manner. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours, dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours at a heating rate of 200℃ / hour. Sulfation was carried out using an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, and the temperature was kept constant at 320℃ for 10 hours. Then, under an atmosphere where the CO2 content was always maintained at 7500μg / g, the catalyst was impregnated in 600mL of hexadiene solvent for 4 hours, and then heat-treated at 400℃ for 10 hours to obtain the finished catalyst D. Example 5

[0023] In a 200 mL fixed-bed small-scale hydrogenation unit, catalysts A, B, C, and D were used respectively, at a hydrogen partial pressure of 5.0 MPa and a liquid hourly space velocity of 0.7 h⁻¹. -1 The hydrogen-to-oil volume ratio is 500 Nm. 3 / m 3 The raw materials in Table 2 were hydrogenated under an average reaction temperature of 340℃.

[0024] Comparative Example 1 100g of alumina support E (water absorption rate 75mL / 100g) was placed in a boiling pot. Under rotating conditions, 75mL of an impregnation solution containing 27.5g of molybdenum trioxide and 22.7g of basic cobalt carbonate was sprayed into the alumina support in the boiling pot via atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours, dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours at a heating rate of 200℃ / hour. Sulfation was carried out using an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, with the temperature raised to 320℃ and held at that temperature for 10 hours. The catalyst was then placed in 600mL of hexadiene solvent for 4 hours, heated at 200℃ for 4 hours, heated to 300℃ for 24 hours, and then heated to 400℃ for 10 hours for heat treatment. The finished catalyst E was obtained without maintaining a CO2 atmosphere.

[0025] Comparative Example 2 100g of alumina support E (water absorption rate 75mL / 100g) was placed in a boiling pot. Under rotating conditions, 75mL of an impregnation solution containing 29.0g of molybdenum trioxide and 19.9g of basic cobalt carbonate was sprayed into the alumina support in the boiling pot by atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours, dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours at a heating rate of 200℃ / hour. Sulfation was carried out using an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, and the temperature was kept constant at 320℃ for 10 hours. Then, under an atmosphere where the CO2 content was always maintained at 700μg / g, the catalyst was impregnated in 600mL of hexadiene solvent for 4 hours, and then heat-treated at 400℃ for 10 hours to obtain the finished catalyst B. The catalyst was prepared by immersing it in 600 mL of hexadiene solvent for 4 hours while maintaining a CO2 content of 700 μg / g in an atmosphere, and then heating it at 400 °C for 10 hours for heat treatment.

[0026] Comparative Example 3 100g of alumina carrier B (water absorption rate 90mL / 100g) was placed in a boiling pot. Under rotating conditions, 90mL of an impregnation solution containing 25.0g of molybdenum trioxide and 16.3g of basic cobalt carbonate was sprayed into the alumina carrier in the boiling pot in an atomized manner. After the solution was sprayed, the pot was rotated for another 30 minutes. The mixture was dried at 120℃ for 6 hours and calcined at 500℃ for 4 hours. Sulfidation was carried out using an in-vessel sulfidation process. The amount of dimethyl disulfide introduced was 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, and the temperature was kept constant at 320℃ for 10 hours.

[0027] Comparative Example 4 100g of alumina support H (water absorption rate 70mL / 100g) was placed in a boiling pot. Under rotating conditions, 70mL of an impregnation solution containing 28.6g of molybdenum trioxide and 16.8g of basic cobalt carbonate was sprayed into the alumina support in the boiling pot by atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, then left to stand for 18 hours, dried at 110℃ for 3 hours, and then calcined at 500℃ for 3 hours at a heating rate of 200℃ / hour. Then, the CO2 content was kept at 6900μg / g under an atmosphere. The mixture was then impregnated in 600mL of hexadiene solvent for 4 hours, and then heat-treated at 400℃ for 10 hours. Sulfation was carried out using an in-vessel sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process used a programmed temperature rise, and the temperature was kept constant at 280℃ for 10 hours to obtain the finished catalyst H.

[0028] Comparative Example 5 Catalysts E, F, G, and H were evaluated separately, using the same evaluation method as in Example 5. Example 6

[0029] This example compares the physicochemical properties of the catalysts prepared in the above examples with the results of operating the above examples on a small-scale hydrogenation unit for 600 hours, as shown in Tables 1 and 2.

[0030] Table 1. Main properties of the catalyst Catalyst number A B C D E F G H Carrier number A B C D E E B H carrier properties <![CDATA[Specific surface area / m 2 .g -1 > 300 310 290 275 302 302 310 265 <![CDATA[Pore volume / cm 3 .g -1 > 0.80 0.78 0.82 0.69 0.59 0.59 0.78 0.50 Average pore size / nm 10.7 10.1 11.3 10.0 7.8 7.8 10.1 7.5 <![CDATA[Pyridine - TPD Acid Content / mmol·g -1 > 0.492 0.533 0.514 0.595 0.385 0.385 0.533 0.365 <![CDATA[Amount of B acid / mmol·g -1 > 0.157 0.168 0.173 0.175 0.083 0.083 0.168 0.063 <![CDATA[Amount of L acid / mmol·g -1 > 0.335 0.365 0.341 0.42 0.302 0.302 0.365 0.302 B acid / L acid 0.469 0.460 0.507 0.417 0.275 0.275 0.460 0.209 Catalyst properties C,wt% 7.9 9.6 10.7 7.3 8.9 10.1 - 7.5 <![CDATA[MoS2,wt%]]> 21.1 22.2 20.0 22.2 21.1 22.2 20.0 22.2 <![CDATA[Co9S8, wt%]]> 9.3 8.2 7.0 7.0 9.3 8.2 7.0 7.0 Table 2. Test results of the catalyst Catalyst number A B C D E F G H Process conditions Hydrogen partial pressure, MPa 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 <![CDATA[Space velocity, h -1 > 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 Hydrogen-to-oil volume ratio 500 500 500 500 500 500 500 500 Reaction temperature, °C 340 340 340 340 340 340 340 340 Oil properties raw material Oil produced Oil produced Oil produced Oil produced Oil produced Oil produced Oil produced Oil produced Sulfur, m% 1.56 0.32 0.30 0.31 0.32 0.63 0.65 0.50 0.82 Nitrogen, m% 0.29 0.20 0.21 0.21 0.2 0.26 0.25 0.24 0.26 (Tricyclic + Tetracyclic) Aromatic Hydrocarbons, m% 45.2 44.7 44.5 44.2 44.4 40.9 41.1 40.9 40.3 (Tricyclic + Tetracyclic) Aromatic Hydrocarbon Loss, m% 0.5 0.7 1.0 0.8 4.3 4.1 4.0 4.9 The results in Table 2 show that the sulfur content in the slurry after hydrorefining of the catalyst of the present invention is <0.4%, and the loss rate of (tricyclic + tetracyclic) aromatics is 2 percentage points, which meets the feed requirements of high-end graphite units.

Claims

1. A process for preparing a slurry selective hydroprocessing catalyst, characterized by The method comprises the following steps: (1) impregnating a hydrogenation catalyst carrier with an impregnating solution containing Mo and Co, drying and calcining the impregnated carrier, and then performing sulfuration treatment; and (2) saturating the catalyst obtained in step (1) after sulfuration with liquid olefins, and then performing closed heat treatment in a CO2 atmosphere with a certain concentration to obtain an oil slurry selective hydrogenation catalyst.

2. The method of claim 1, wherein: The drying condition in step (1) is drying at 100-120 ℃ for 1-5 hours, and the calcining condition is calcining at 400-550 ℃ for 1-5 hours.

3. The method of claim 1, wherein: The sulfuration treatment in step (1) is performed by in-vessel or out-vessel sulfuration, the amount of sulfuration agent introduced is 90%-150% of the theoretical sulfur requirement of the catalyst, the sulfuration process is performed by programmed temperature rising, the temperature is raised to 200-350 ℃ and kept constant for 1-16 hours, and the sulfuration agent is generally one or more of carbon disulfide, dimethyl disulfide, methyl sulfide and n-butyl sulfide.

4. The method of claim 1, wherein: The liquid olefins in step (2) are one or more of olefins and diolefins with 2-10 carbon atoms, and preferably hexadiene and / or n-heptene.

5. The method of claim 1, wherein: The closed heat treatment process in step (2) is performed at 300-400 ℃ for 1-72 hours in a closed container.

6. The method of claim 1, wherein: The closed heat treatment process in step (2) is performed at 50-250 ℃ for 1-8 hours, then at 250-300 ℃ for 1-72 hours, and then at 300-400 ℃ for 1-72 hours.

7. The method of claim 1, wherein: The CO2 concentration in step (2) is ≮3000 μg / g, and preferably ≮6000 μg / g.

8. The slurry oil selective hydrocatalyst prepared according to the process of claims 1-6, characterized by: The catalyst comprises active metals Mo and Co and a carrier γ-Al2O3, the MoS2 content is 10wt%-52wt%, preferably 16wt%-39wt%, the Co9S8 content is 2wt%-13wt%, preferably 4wt%-11wt%, the carbon content is 0.5wt%-18.0wt%, preferably 5wt%-18.0wt%, and the carrier content is the balance.

9. The slurry oil selective hydrogenation catalyst of claim 7, wherein: The average pore size of the γ-Al2O3 is 8.0-12.0 nm, preferably 8.5-11.5 nm, the specific surface area is 270-330 m2·g-1, preferably 280-320 m2·g-1, the pore volume is 0.66-0.99 cm3·g-1, preferably 0.68-0.80 cm3·g-1, the total amount of pyridine-infrared acid is 0.4-0.7 mmol·g-1, preferably 0.45-0.65 mmol·g-1, the amount of B acid is 0.13-0.20 mmol·g-1, preferably 0.15-0.18 mmol·g-1, the amount of L acid is 0.20-0.57 mmol·g-1, preferably 0.27-0.50 mmol·g-1, and the ratio of B acid / L acid is 0.30-1.00, preferably 0.35-0.

66. 2 ·g -1 ·g 3 ·g -1 ·g 3 ·g -1 ·g -1 ·g -1 ·g -1 ·g -1 ·g -1 ·g -1 ·g 10. An application of an oil slurry selective hydrogenation catalyst prepared by the method of claims 1-6 in an oil slurry selective hydrogenation process, and the process conditions are as follows: pressure 4.0-6.0 MPa, space velocity 0.5-1.0 h-1, temperature 300-390 ℃, and hydrogen / oil volume ratio 100-800.