A method for preparing a hydrodesulfurization catalyst

Abstract

This invention discloses a method for preparing a hydrodesulfurization catalyst, comprising the following steps: (1) impregnating a support with an impregnation solution containing the active metal Mo, followed by drying and calcination of the impregnated support, and then performing sulfidation treatment; (2) saturating the catalyst after sulfidation in step (1) with liquid olefins, followed by heat treatment, with the entire process completed in a closed equipment under a certain amount of CO2 atmosphere; (3) impregnating the heat-treated catalyst obtained in step (2) with an impregnation solution containing the active metal Co, followed by drying, calcination, and sulfidation to obtain the hydrodesulfurization catalyst. This invention achieves high activity and high selectivity of the catalyst in the selective hydrodesulfurization process of gasoline by protecting the desulfurization active centers of MoS2, then performing carbon deposition treatment on the olefin-saturated active centers, and further promoting the desulfurization active centers of MoS2 through the auxiliary agent Co.

Description

Technical Field

[0001] This invention belongs to the field of petroleum refining, and specifically relates to a method for preparing a hydrodesulfurization catalyst. Background Technology

[0002] With increasingly stringent environmental regulations, countries worldwide are demanding lower sulfur content in clean gasoline to effectively control harmful emissions from vehicle exhaust. In my country, catalytic cracking (FCC) gasoline constitutes a large proportion of the gasoline mix and is the primary contributor to sulfur in finished gasoline. Therefore, deep desulfurization of FCC gasoline is crucial to meeting my country's standards for finished gasoline.

[0003] Representative FCC gasoline selective hydrodesulfurization technology abroad includes Prime-G developed by the French company Axens. + Exxon Mobil has developed SCANfining technology. In China, the OCT-M, OCT-MD, and OCT-ME series technologies, as well as the RSDS-I, RSDS-II, and RSDS-III series technologies, are widely used in industrial applications. These technologies provide effective technical support for refineries to address oil quality upgrades. The core of these technologies is to effectively improve the selectivity of heavy gasoline hydrodesulfurization. Therefore, the development of high-selectivity heavy gasoline hydrodesulfurization catalysts is crucial.

[0004] CN111111701A discloses a hydrodesulfurization catalyst and its preparation method. The preparation method of the hydrodesulfurization catalyst includes the following steps: (1) loading active metals Co and Mo onto a support, drying and calcining to obtain a semi-finished catalyst; (2) saturating the semi-finished catalyst with liquid olefins, and then heat-treating it; (3) subjecting the heat-treated catalyst to sulfidation treatment to obtain the catalyst. Although this catalyst, obtained through a special coking method, has longer active phase crystals and more stack layers after sulfidation, and this structure of the sulfidated catalyst has better hydrodesulfurization selectivity, the coking process inevitably damages the desulfurization activity to some extent, and cannot effectively suppress the olefin saturated active centers. The desulfurization activity and hydrodesulfurization selectivity of this catalyst need to be further improved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing a hydrodesulfurization catalyst. This method protects the desulfurization active sites of MoS2, then performs carbon deposition treatment on the olefin-saturated active sites, and further promotes the desulfurization active sites of MoS2 through the auxiliary agent Co, thereby achieving high catalyst activity and high selectivity in gasoline hydrogenation during selective hydrodesulfurization of gasoline.

[0006] The preparation method of the hydrodesulfurization catalyst of the present invention includes the following steps:

[0007] (1) The carrier is impregnated with an impregnation solution containing active metal Mo. After impregnation, the carrier is dried and calcined, and then subjected to sulfidation treatment.

[0008] (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.

[0009] (3) The heat-treated material obtained in step (2) is impregnated with an impregnation solution containing active metal Co, and then dried, roasted and sulfided to obtain a hydrodesulfurization catalyst.

[0010] In the method of this invention, the carrier in step (1) is an inorganic refractory oxide, selected from one or more of alumina, silicon oxide, zirconium oxide, titanium oxide, and magnesium oxide, preferably alumina. The carrier can be modified by adding additives, and the modifying additives can be K, Na, Mg, Si, P, Zr, or Ti.

[0011] In the method of the present invention, the preparation method of the impregnation solution containing active metal Mo is well known to those skilled in the art. For example, it can be prepared by adding ammonium molybdate to ammonia water, dissolving it, and then adjusting the solution volume to the final volume with ammonia water and storing it in a sealed container.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] In the method of the present invention, the CO2 concentration in step (2) is ≥3000μg / g, preferably ≥6000μg / g.

[0017] In the method of the present invention, the preparation method of the impregnation solution containing active metal Co in step (2) is to first dissolve citric acid in purified water, add cobalt carbonate, boil to dissolve, cool, adjust the volume of the solution to the final volume with purified water, and store it in a sealed container.

[0018] In the method of the present invention, the drying conditions in step (2) are: drying at 100~120℃ for 1~5 hours; the calcination conditions are: calcination at 300~350℃ for 3~4 hours. The vulcanization process adopts the vulcanization method in step (1).

[0019] The hydrodesulfurization catalyst of the present invention, based on the total weight of the catalyst, comprises 2.0% to 30.0% MoS2, preferably 2.0% to 25.0%, 0.1% to 7.0%, preferably 0.1% to 6.0%, 0.5% to 18.0%, preferably 5% to 18.0%, and the balance being the support content; the support is an inorganic refractory oxide selected from one or more of alumina, silicon oxide, zirconium oxide, titanium oxide or magnesium oxide, preferably alumina.

[0020] The hydrodesulfurization catalyst of this invention has a pore volume of 0.3~1.3 mL / g and a specific surface area of ​​150~400 m². 2 / g, strength 100~250N / cm, bulk density 0.65~0.90g / mL.

[0021] The hydrodesulfurization catalyst of the present invention may also be supplemented with additives as needed, such as one or more of the additive elements K, Na, Mg, Si, P, Zr or Ti. Based on the total weight of the catalyst, the amount of additives added as oxides is 1.0% to 10%, and the sum of the contents of all components of the catalyst is 100%.

[0022] The hydrodesulfurization catalyst of the present invention is suitable for use in selective hydrodesulfurization of gasoline.

[0023] In the selective hydrogenation of gasoline, balancing the performance of the catalyst in hydrodesulfurization with the inhibition of olefin hydrogenation saturation has always been a challenging task. The inventors first impregnated the catalyst with Mo active metal, followed by drying, calcination, and sulfidation to form the MoS2 active phase. They then cleverly utilized the different active sites on the catalyst in the hydrodesulfurization and olefin hydrogenation saturation reactions to adsorb a large amount of acidic CO2 molecules onto the active sites of the hydrodesulfurization reaction. After impregnation with liquid olefins and subsequent heat treatment to form carbon deposits, the CO2 molecules protect the active sites of the hydrodesulfurization reaction, causing the carbon deposits to primarily cover the active sites of the olefin hydrogenation saturation reaction, thus inhibiting olefin saturation activity. Furthermore, impregnation with Co active metal prevents the sulfided Co active metal from being encapsulated by the sulfided Mo active metal, and also promotes the activity of the Mo active metal. Since carbon deposits mainly cover the active sites of olefin hydrogenation saturation reaction, while carbon deposits are not obvious on the active sites of hydrodesulfurization reaction protected by CO2 molecule adsorption, the promoting effect of Co active metal on Mo active metal is mainly concentrated on the hydrodesulfurization active sites, thus increasing the hydrodesulfurization activity and selectivity of the catalyst. Detailed Implementation

[0024] In this invention, the specific surface area and pore volume are determined by the low-temperature liquid nitrogen adsorption method, the strength is determined by the intelligent particle strength tester, and the bulk density is determined by the graduated cylinder method.

[0025] The specific preparation process of the catalyst of this invention is as follows:

[0026] The carrier is placed in a rotating pot. While rotating, a Mo-ammonia solution saturated with the carrier's water absorption capacity is sprayed onto the carrier in a mist manner. After spraying, the pot is rotated 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-plant 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 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. The sulfided material is heat-treated at 300-400℃ for 1-72 hours. The resulting sulfided material is placed in a cauldron and, under rotating conditions, a Co solution with the saturated water absorption capacity of the sulfided material is sprayed into the cauldron in an atomized manner. After the solution is sprayed out, the cauldron continues to rotate for 10-60 minutes, and then left to stand for 1-24 hours. It is then dried at 100-120℃ for 1-5 hours, and then calcined at 300-350℃ for 3-4 hours at a heating rate of 150-250℃ / hour. Finally, it is sulfided using an in-vessel or out-of-vessel sulfidation process. The amount of sulfiding agent introduced is 90%-150% of the theoretical sulfur required for the catalyst. The sulfidation process uses programmed temperature rise, and the temperature is kept constant at 200-350℃ for 1-16 hours to obtain the finished catalyst.

[0027] In the above preparation method, the concentration of the impregnation solution is determined by the water absorption rate and the required catalyst composition (content).

[0028] The catalysts used in this invention are described in detail below using examples. Example 1

[0029] 19.2 g of ammonium molybdate was added to 130 mL of 25% (by weight) ammonia water, dissolved, and the solution volume was adjusted to 150 mL with 25% ammonia water and stored in a sealed container. 200 g of the support was placed in a boiling pan and sprayed with 150 mL of the prepared molybdenum and ammonia solution. After spraying, the pan was rotated for 30 minutes, then left to stand for 18 hours, dried at 110 °C for 3 hours, and then calcined at 500 °C for 3 hours at a heating rate of 200 °C / hour. Then, under an atmosphere where the CO2 content was always 6900 μg / g, the support was impregnated in 600 mL of hexadiene solvent for 4 hours, heated at 200 °C for 4 hours, heated to 300 °C for 24 hours, and then heated to 400 °C for 10 hours for heat treatment to obtain a single-stage oxidized catalyst A. A first-stage oxidized catalyst A was subjected to an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a constant temperature of 280℃ for 10 hours to obtain the first-stage sulfidated catalyst A. The first-stage sulfidated catalyst A was placed in a rotating pot, and under rotating conditions, 80 mL of an aqueous solution containing 14.3 g of citric acid and 10.2 g of cobalt carbonate was sprayed onto the alumina support in the pot via atomization. After the solution was sprayed out, the pot was rotated for another 30 minutes, dried at 110℃ for 4 hours, and calcined at 300℃ for 3 hours. The sulfidation process was then 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 employed a programmed temperature rise, maintaining a constant temperature of 280℃ for 10 hours to obtain the finished catalyst A. Example 2

[0030] 10.5 g of ammonium molybdate was added to 130 mL of 25% (by weight) ammonia water and dissolved. The solution volume was then adjusted to 150 mL with 25% ammonia water and stored in a sealed container. 200 g of the support was placed in a boiling pan and sprayed with 150 mL of the prepared molybdenum ammonia solution. After spraying, the pan was rotated for 30 minutes and then left to stand for 18 hours. It was then dried at 110 °C for 3 hours, and then calcined at 500 °C for 3 hours at a heating rate of 200 °C / hour. Then, under an atmosphere where the CO2 content was always 4700 μg / g, the catalyst was immersed in 600 mL of hexadiene solvent for 4 hours and then heat-treated at 400 °C for 10 hours to obtain a single-stage oxidized catalyst B. A first-stage oxidized catalyst B was subjected to an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a temperature of 280℃ for 10 hours to obtain the first-stage sulfidated catalyst B. The first-stage sulfidated catalyst B was placed in a rotating pot, and 90 mL of an aqueous solution containing 8.3 g of citric acid and 5.9 g of cobalt carbonate was sprayed onto the alumina support in the pot via atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, dried at 110℃ for 4 hours, and then dried at 350℃ for 3 hours. The same external sulfidation process was then performed, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a temperature of 280℃ for 10 hours to obtain the finished catalyst B. Example 3

[0031] 29.4 g of ammonium molybdate was added to 135 mL of 25% (by weight) ammonia water, dissolved, and the solution volume was adjusted to 150 mL with 25% ammonia water and stored in a sealed container. 200 g of the support was placed in a boiling pan and sprayed with 150 mL of the prepared molybdenum ammonia solution. After spraying, the pan was rotated for 30 minutes, then left to stand for 18 hours, dried at 110 °C for 3 hours, and then calcined at 500 °C for 3 hours at a heating rate of 200 °C / hour. Then, under an atmosphere where the CO2 content was always 5800 μg / g, the support was impregnated in 600 mL of hexadiene solvent for 4 hours, heated at 200 °C for 4 hours, heated to 300 °C for 24 hours, and then heated to 400 °C for 10 hours for heat treatment to obtain a single-stage oxidized catalyst C. A first-stage oxidized catalyst C was subjected to an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a temperature of 280℃ for 10 hours to obtain the first-stage sulfidated catalyst C. The first-stage sulfidated catalyst C was then placed in a rotating pan. Under rotating conditions, 76 mL of an aqueous solution containing 17.3 g of citric acid and 12.4 g of cobalt carbonate was sprayed onto the alumina support in the pan via atomization. After the solution was sprayed out, the pan was rotated for another 30 minutes, dried at 110℃ for 4 hours, and then dried at 300℃ for 4 hours. The same external sulfidation process was then performed, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a temperature of 280℃ for 10 hours to obtain the final catalyst C. Example 4

[0032] 40.1 g of ammonium molybdate was added to 130 mL of 25% (by weight) ammonia water, dissolved, and the solution volume was adjusted to 150 mL with 25% ammonia water. The solution was then sealed and stored. 200 g of the support was placed in a boiling pan and sprayed with 150 mL of the prepared molybdenum ammonia solution. After spraying, the pan was rotated for 30 minutes, then left to stand for 18 hours. It was then dried at 110 °C for 3 hours, and then calcined at 500 °C for 3 hours at a heating rate of 200 °C / hour. Then, under an atmosphere where the CO2 content was always maintained at 7500 μg / g, it was placed in 600 mL of hexadiene solvent for 4 hours and then heat-treated at 400 °C for 10 hours to obtain a single-stage oxidized catalyst D. A first-stage oxidized catalyst D was subjected to an external sulfidation process, with the amount of dimethyl disulfide introduced being 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process employed a programmed temperature rise, maintaining a constant temperature of 280℃ for 10 hours to obtain the first-stage sulfidated catalyst D. The first-stage sulfidated catalyst D was placed in a rotating pot, and under rotating conditions, 76 mL of an aqueous solution containing 19.4 g of citric acid and 13.8 g of cobalt carbonate was sprayed onto the alumina support in the pot via atomization. After the solution was sprayed, the pot was rotated for another 30 minutes, dried at 110℃ for 4 hours, and calcined at 350℃ for 4 hours. The sulfidation process was then 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 employed a programmed temperature rise, maintaining a constant temperature of 280℃ for 10 hours to obtain the finished catalyst D.

[0033] Comparative Example 1

[0034] The preparation process is the same as in Example 1, except that the catalyst E is prepared by immersion in 600 mL of hexadiene solvent for 4 h, followed by heating at 200 °C for 4 h, heating at 300 °C for 24 h, and then heating at 400 °C for 10 h for heat treatment. This process is not carried out under a CO2 atmosphere.

[0035] Comparative Example 2

[0036] The preparation process is the same as in Example 2, except that the CO2 content is always kept at 700 μg / g under the atmosphere, and the catalyst is immersed in 600 mL of hexadiene solvent for 4 h, and then heated at 400 °C for 10 h for heat treatment to obtain a single-stage oxidized catalyst F.

[0037] Comparative Example 3

[0038] Dissolve 21.7g of citric acid in 65mL of purified water, add 16.1g of cobalt carbonate, boil to dissolve, cool, then add 25% (by weight) ammonia to 135mL, add 33.1g of ammonium molybdate to the above solution, dissolve, and adjust the solution volume to 150mL with 25% ammonia, then store in a sealed container. Place 200g of the support in a boiling pan, spray with 150mL of the prepared molybdenum and cobalt ammonia solution. After spraying, continue to rotate in the boiling pan for 30 minutes, then let stand for 18 hours, dry at 110℃ for 3 hours, then calcine at 500℃ for 3 hours with a heating rate of 200℃ / hour, then keep the CO2 content at 6900μg / g atmosphere, and impregnate in 600mL of hexadiene solvent for 4 hours, then heat-treat at 400℃ for 10 hours to obtain a single-stage oxidized catalyst G. The oxidized catalyst G was subjected to an external sulfidation process. The amount of dimethyl disulfide introduced was 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process adopted a programmed temperature rise, and the temperature was raised to 280℃ and held for 10 hours to obtain the finished catalyst G.

[0039] Comparative Example 4

[0040] Dissolve 25.9 g of citric acid in 40 mL of purified water, add 19.3 g of cobalt carbonate, boil to dissolve, cool, then add 25% (by weight) ammonia to 130 mL, add 45.3 g of ammonium molybdate to the above solution, dissolve, and adjust the solution volume to 150 mL with 25% ammonia, then store in a sealed container. Place 200 g of the support in a boiling pan, spray it with 150 mL of the prepared molybdenum and cobalt ammonia solution, continue to rotate in the boiling pan for 30 minutes after spraying, then let it stand for 18 hours, dry it at 110 °C for 3 hours, then calcine it at 500 °C for 3 hours at a heating rate of 200 °C / hour, then impregnate it in 600 mL of hexadiene solvent for 4 hours, and then heat-treat it at 400 °C for 10 hours to obtain a single-stage oxidized catalyst H. Catalyst H was subjected to in-plant sulfidation treatment. The amount of dimethyl disulfide introduced was 120% of the theoretical sulfur requirement of the catalyst. The sulfidation process adopted programmed temperature rise, and the temperature was raised to 280℃ and held for 10 hours to obtain the finished catalyst H. Example 5

[0041] In a 200 mL fixed-bed small-scale hydrogenation unit, catalysts A, B, C, D, E, F, G, and H were used (catalyst properties are shown in Table 1) at a reaction pressure of 1.6 MPa and a liquid hourly space velocity of 3.0 h⁻¹. -1 The hydrogen-to-oil volume ratio is 300 Nm 3 / m 3 Selective hydrodesulfurization was performed on gasoline feedstock with a sulfur content of 664 μg / g and RON of 93.0. The evaluation results of each catalyst after 600 hours of operation are shown in Table 2.

[0042] Table 1. Main properties of the catalyst

[0043] Catalyst number A B C D E F G H C,wt% 7.9 9.6 10.7 7.3 8.9 10.1 9.2 7.5 <![CDATA[MoS2,wt%]]> 7.9 4.5 11.5 14.9 7.8 4.4 12.9 16.6 <![CDATA[Co9S8, wt%]]> 2.9 1.7 3.5 3.9 2.8 1.6 3.9 4.4 Pore ​​volume, mL / g 0.42 0.46 0.45 0.42 0.41 0.45 0.44 0.39 <![CDATA[Specific surface area, m 2 / g]]> 238 239 224 223 231 235 196 179 Bulk density, g / mL 0.73 0.72 0.75 0.77 0.73 0.73 0.78 0.80 Strength, N / cm 132 148 137 136 129 123 127 129

[0044] Table 2 Catalyst Activity and Selectivity

[0045] catalyst A B C D E F G H Reaction temperature, °C 270 310 260 250 270 320 280 270 Sulfur, μg / g 8.1 8.6 8.2 8.0 9.2 9.4 9.5 9.4 RON 91.9 91.8 91.7 91.9 91.5 91.5 91.4 91.4 RON loss 1.1 1.2 1.3 1.1 1.5 1.5 1.6 1.6

[0046] Reaction conditions: P = 1.6 MPa; LHSV = 3.0 h⁻¹ -1 H2 / Oil = 300 Nm 3 / m 3

[0047] The results in Table 2 show that the catalyst of the present invention has better hydrodesulfurization selectivity and less octane number loss under the same desulfurization rate.

Claims

1. A method for preparing a hydrodesulfurization catalyst, characterized in that... The following contents are included: (1) Impregnating the carrier with an impregnation solution containing active metal Mo, and after impregnation, the carrier is dried and calcined, and then subjected to sulfidation treatment; (2) After sulfidation in step (1), the catalyst is saturated with liquid olefins and then subjected to closed heat treatment under a certain concentration of CO2 atmosphere; (3) Impregnating the heat-treated material obtained in step (2) with an impregnation solution containing active metal Co, and after drying, calcination and sulfidation, a hydrodesulfurization catalyst is obtained; the CO2 concentration in step (2) is ≥3000μg / g; the closed heat treatment process in step (2) is: heat treatment at 300~400℃ for 1~72h in a closed container.

2. The method according to claim 1, characterized in that: The carrier mentioned in step (1) is an inorganic refractory oxide, selected from one or more of alumina, silicon oxide, zirconium oxide, titanium oxide, and magnesium oxide.

3. The method according to claim 1, characterized in that: The drying conditions for step (1) are: drying at 100~120℃ for 1~5 hours; the calcination conditions are: calcination at 400~550℃ for 1~5 hours.

4. The method according to claim 1, characterized in that: The sulfidation process described in step (1) is an in-device or out-of-device sulfidation process. The amount of sulfiding agent introduced is 90% to 150% of the theoretical sulfur required by the catalyst. The sulfidation process adopts programmed temperature rise, and the temperature is raised to 200 to 350℃ and held for 1 to 16 hours. The sulfiding agent is one or more of carbon disulfide, dimethyl disulfide, methyl sulfide, and n-butyl sulfide.

5. The method according to claim 1, characterized in that: The liquid olefin mentioned in step (2) is one or more of olefins and dienes with 2 to 10 carbon atoms.

6. The method according to claim 1, characterized in that: The liquid olefins mentioned in step (2) are hexadiene and / or n-heptene.

7. The method according to claim 1, characterized in that: The CO2 concentration mentioned in step (2) is ≥6000μg / g.

8. The method according to claim 1, characterized in that: The closed heat treatment process in step (2) is as follows: in a closed container, heat at 50~250℃ for 1~8h, raise the temperature to 250~300℃ for 1~72h, and then raise the temperature to 300~400℃ for 1~72h.

9. The method according to claim 1, characterized in that: The drying conditions in step (3) are: drying at 100~120℃ for 1~5 hours; the calcination conditions are: calcination at 300~350℃ for 3~4 hours; the sulfidation process is an in-vessel or out-of-vessel sulfidation process, the amount of sulfiding agent introduced is 90%~150% of the theoretical sulfur required by the catalyst, the sulfidation process adopts programmed temperature rise, the temperature is raised to 200~350℃ and kept at a constant temperature for 1~16 hours, and the sulfiding agent is one or more of carbon disulfide, dimethyl disulfide, methyl sulfide, and n-butyl sulfide.

10. A hydrodesulfurization catalyst prepared by the method according to any one of claims 1 to 9, characterized in that: Based on the total weight of the catalyst, MoS2 is 2.0%~30.0%, Co9S8 is 0.1%~7.0%, carbon content is 0.5%~18.0%, and the support content is the balance; the support is an inorganic refractory oxide selected from one or more of alumina, silicon oxide, zirconium oxide, titanium oxide, or magnesium oxide.

11. The catalyst according to claim 10, characterized in that: The pore volume of the hydrodesulfurization catalyst is 0.3~1.3 mL / g, and the specific surface area is 150~400 m². 2 / g, strength 100~250N / cm, bulk density 0.65~0.90g / mL.

12. The application of a hydrodesulfurization catalyst prepared by any one of claims 1 to 9 in the selective hydrodesulfurization of gasoline.