A hydrorefining catalyst and its preparation method and application

Abstract

The present invention discloses a hydrorefining catalyst, its preparation method, and application. The hydrorefining catalyst comprises a support and an active metal selected from Group VIB and Group VIII metals. The catalyst comprises a tetracoordinated Group VIB metal species to a hexacoordinated Group VIB metal species in an atomic ratio of 20:1 to 2:1. The hydrorefining catalyst of the present invention exhibits excellent stability and can extend the operating cycle of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrorefining, and in particular to a hydrorefining catalyst, a preparation method and application thereof. Background Art

[0002] Since the implementation of the National VI standard for gasoline and diesel, refineries have been under pressure to produce ultra-low sulfur diesel. The removal of sulfides from diesel can generally be achieved through methods such as oxidative desulfurization, biological desulfurization, adsorption, and hydrodesulfurization. Hydrodesulfurization is the most effective method for effectively reducing the sulfur content in diesel and improving the quality of diesel products. For conventional diesel hydrorefining processes, the diesel hydrotreating unit can maintain an operating cycle of approximately eight years while stably producing low-sulfur diesel. However, when processing low-sulfur diesel feedstocks, the diesel hydrotreating unit faces the problem of catalyst desulfurization and poor stability, which seriously affects the continuous, efficient, and stable operation of the diesel hydrotreating unit. Abnormal shutdowns during the production of the diesel hydrotreating unit also place tremendous pressure on the overall production balance of the plant and the stable delivery of diesel products. Therefore, it is necessary to develop highly stable diesel hydrotreating catalysts to address the poor stability of conventional diesel hydrotreating catalysts when processing low-sulfur diesel feedstocks.

[0003] CN102151582A discloses a method for preparing a high-nitrogen, low-quality gasoline and diesel hydrodesulfurization catalyst. This method uses a mixture of Al2O3-TiO2-SiO2 mixed oxides and aluminum oxide as a carrier; the active metals are nickel, molybdenum, and tungsten oxides; and the additive is phosphorus. A W-Mo-Ni-P co-impregnation solution with good solubility is used to distribute the different metal components, W, Mo, and Ni, along with the additive P, to produce a highly active hydrorefining catalyst. The addition of an electronic additive modifies the interaction between the metal and the carrier, increasing the proportion of unstable hexacoordinated molybdenum or tungsten metals and reducing their stability.

[0004] CN1952059A discloses a distillate hydrodearomatization catalyst and its application. The catalyst prepared by this method is doped with Y molecular sieve and stabilizers iron / zinc. The iron or zinc in the stabilizer can react with sulfur to form stable sulfides in a limited manner, reducing sulfur loss in the active phase. Under the action of the Y molecular sieve with strong ring-opening ability, the catalyst can maintain good activity and selectivity in a low-sulfur or sulfur-free reaction atmosphere. This catalyst can not only be used in the diesel hydrodearomatization process, but also can be applied to the second-stage hydrogenation reactor in a low-sulfur atmosphere, thereby achieving long-term operation of the device. However, this method can easily cause catalyst aggregation, resulting in a rapid increase in the reactor pressure drop. Summary of the Invention

[0005] In order to address the shortcomings of the prior art, the present invention provides a hydrorefining catalyst and its preparation method and application. The hydrorefining catalyst prepared by the method of the present invention can improve the stability of the hydrorefining catalyst and achieve the purpose of extending the operating cycle of the device.

[0006] A first aspect of the present invention provides a hydrotreating catalyst comprising: a carrier and an active metal, wherein the active metal is selected from Group VIB metals and Group VIII metals, and wherein the ratio of the tetracoordinated Group VIB metal species to the hexacoordinated Group VIB metal species in terms of atoms is 20:1 to 2:1, preferably 15:1 to 4:1.

[0007] Furthermore, the hydrotreating catalyst further comprises an additive, wherein the additive is carbon, and the carbon is derived from at least one carbon-containing substance such as coke and graphite.

[0008] Furthermore, the hydrotreating catalyst further comprises a binder, and the binder is derived from aluminum sol.

[0009] Furthermore, the Group VIB metal is selected from W and / or Mo, and the Group VIII metal is selected from Co and / or Ni.

[0010] Furthermore, the carrier is selected from alumina, and the crystal form of the alumina includes at least one of α-alumina, β-alumina, γ-alumina, δ-alumina, θ-alumina, η-alumina, etc., preferably γ-alumina and / or η-alumina.

[0011] Furthermore, based on the weight of the hydrotreating catalyst, the content of the carrier is 50% to 80%, preferably 55% to 75%, and the content of the active metal in terms of oxide is 20% to 50%, preferably 25% to 44%, wherein, among the active metals, the content of the Group VIII metal in terms of oxide is 3% to 12%, preferably 4% to 10%, and the content of the Group VIB metal in terms of oxide is 8% to 47%, preferably 15% to 40%.

[0012] Furthermore, the content of the additive is 12% or less based on the weight of the hydrotreating catalyst.

[0013] Furthermore, the binder content is 8% or less based on the weight of the hydrotreating catalyst.

[0014] The second aspect of the present invention provides a method for preparing the above-mentioned hydrorefining catalyst, comprising:

[0015] (1) impregnating a support raw material with a solution containing an active metal precursor, followed by drying and calcining to obtain a hydrorefining catalyst intermediate;

[0016] (2) mixing the hydrorefining catalyst intermediate obtained in step (1) with an additive component, and calcining under an inert gas; when the mass loss of the hydrorefining catalyst intermediate is 60% to 100%, preferably 70% to 95%, of the amount of the additive component added, cooling and stopping the calcination to obtain a hydrorefining catalyst powder;

[0017] (3) The hydrorefining catalyst powder is mixed with the binder component, molded, dried, and calcined to obtain the hydrorefining catalyst.

[0018] Furthermore, in step (1), the active metal precursor is selected from at least one of its soluble salts. For example, when Mo is selected as the main active metal, the precursor is selected from at least one of ammonium molybdate, ammonium molybdate tetrahydrate, ammonium molybdate hexahydrate, and sodium molybdate, preferably ammonium molybdate hexahydrate. When W is selected as the main active metal, the precursor is selected from at least one of sodium tungstate, ammonium paratungstate, and ammonium metatungstate, preferably ammonium metatungstate. When Ni is selected as the auxiliary active metal, the precursor is selected from at least one of nickel sulfate, nickel nitrate, and nickel nitrate hexahydrate, preferably nickel nitrate hexahydrate. When Co is selected as the auxiliary active metal, the precursor is selected from at least one of cobalt sulfate, cobalt nitrate, and cobalt chloride, preferably cobalt nitrate.

[0019] Furthermore, the impregnation method in step (1) can be one of equal volume impregnation method, excess volume impregnation method, steam impregnation method, etc., preferably equal volume impregnation method.

[0020] Furthermore, in step (1), the drying temperature is 60 to 120° C., preferably 70 to 100° C., and the drying time is 4 to 12 hours, preferably 6 to 10 hours.

[0021] Furthermore, in step (1), the calcination temperature is 200-700° C., preferably 300-600° C., the calcination time is 2-12 h, preferably 4-6 h, and the calcination atmosphere is air or oxygen.

[0022] Furthermore, in step (2), the mass ratio of the hydrotreating catalyst intermediate to the additive component is 40:1 to 5:1, preferably 30:1 to 10:1.

[0023] Furthermore, in step (2), the inert gas is at least one of nitrogen, helium, argon and the like, and the calcination temperature is 300-800°C.

[0024] Furthermore, in step (2), the calcination is carried out in two stages. The first stage calcination conditions are: the calcination temperature is increased from room temperature at 3-12°C / h, preferably at 5-10°C / h, to 300-450°C, and the first constant temperature is carried out for 2-6 hours; the second stage calcination conditions are: the calcination temperature is further increased at 2-7°C / h, preferably at 2-5°C / h, to 460-800°C, and the second constant temperature is carried out for a second time determined according to the mass loss of the hydrorefining catalyst intermediate. The room temperature is 5-35°C.

[0025] Furthermore, in step (3), the adhesive component is selected from at least one of aluminum sol, sesbania powder, etc., preferably sesbania powder.

[0026] Furthermore, in step (3), mixing and shaping can be carried out in a conventional manner in the art, such as by fully rolling and then shaping. The shaped shape can be one or more of a clover, a four-leaf clover, a cylinder, and a toothed ball.

[0027] Furthermore, in step (3), the drying temperature is 50 to 100° C., preferably 60 to 80° C.; and the drying time is 4 to 24 hours, preferably 6 to 10 hours.

[0028] Furthermore, in step (3), the calcination temperature is 200-400° C., preferably 250-350° C.; and the calcination time is 2-10 h, preferably 4-8 h.

[0029] The third aspect of the present invention provides the use of the above-mentioned hydrorefining catalyst in a diesel hydrorefining process.

[0030] Furthermore, the feedstock for the hydrotreating process is a low-sulfur, high-nitrogen diesel feedstock having a sulfur content of 100 to 1000 ppm, preferably 200 to 800 ppm, and a nitrogen content of 200 to 1400 ppm, preferably 300 to 1200 ppm, by mass.

[0031] Furthermore, in the hydrofining process, the reaction conditions of the refining reactor are generally as follows: reaction pressure of 4.0-14.0 MPa, reaction temperature of 300-440°C, volume space velocity of 0.5-4.0 h -1 Preferably, the reaction pressure is 6.0 to 8.0 MPa, the reaction temperature is 320 to 420 ° C, and the volume space velocity is 1.0 to 2.0 h -1 .

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The active phase of the hydrorefining catalyst is divided into tetracoordinate and hexacoordinate active species. The interaction between the hexacoordinate species and the carrier is weak, the stability is poor but the hydrogenation performance is strong; while the interaction between the tetracoordinate species and the carrier is strong, the stability is good but the hydrogenation performance is weak. The present invention is aimed at low-sulfur and high-nitrogen raw materials, and coke is doped in the preparation process of the hydrorefining catalyst. The coke moderately reduces the unstable hexacoordinate molybdenum / tungsten species on the surface of the hydrorefining catalyst to highly stable tetracoordinate molybdenum / tungsten at an appropriate temperature, which can significantly improve the stability and anti-sulfurization ability of the hydrorefining catalyst, thereby extending the operation cycle of the device.

[0034] (2) The hydrorefining catalyst prepared by the method of the present invention has good hydrogenation performance, low hydrogen consumption and long operating cycle.

[0035] (3) In the catalyst preparation method of the present invention, by adopting a staged roasting method, the reduction degree of the hydrorefining intermediate can be effectively controlled, thereby avoiding the problem of excessive or insufficient reduction of the active components of the hydrorefining catalyst. DETAILED DESCRIPTION

[0036] The preparation method and application of the hydrotreating catalyst provided by the present invention will be further described below in conjunction with the examples to compare and reflect the effects and advantages of the hydrotreating catalyst prepared by the preparation method of the present invention, but the present invention is not limited thereto.

[0037] 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.

[0038] In the present invention, the ratio of the tetracoordinated VIB Group metal species to the hexacoordinated VIB Group metal species is analyzed using an H2-TPR instrument. The reduction peak attributable to the hexacoordinated species in the first low-temperature zone and the reduction peak attributable to the tetracoordinated species in the second high-temperature zone are split and fitted to obtain the ratio of the VIB Group metal species with different coordination numbers. This ratio is calculated as the metal atomic ratio.

[0039] The feedstock oil used in the following Examples and Comparative Examples was low-sulfur diesel, the properties of which are shown in Table 1. The Examples were loaded with the hydrotreating catalyst prepared according to the present invention, while the Comparative Examples were loaded with the hydrotreating catalyst of the Comparative Example. Both the Examples and Comparative Examples were evaluated for 2500 hours under the conditions shown in Table 2 to examine the stability of the different catalysts. The evaluation results for the Examples are shown in Table 3, and the evaluation results for the Comparative Examples are shown in Table 4.

[0040] In the present invention, unless otherwise specified, percentages refer to mass fractions.

[0041] The bracketed order in this invention is only for the convenience of reading and review and has no particular order.

[0042] Example 1

[0043] The catalyst preparation method of this embodiment is as follows: a solution of a certain concentration is prepared using a γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source. The carrier is impregnated by an equal volume co-impregnation method, dried at 80°C for 6 hours, and then calcined at 400°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, a hydrorefining catalyst intermediate having an alumina content of 60%, a MoO3 content of 35wt%, and a CoO content of 5wt% is obtained, respectively, in terms of MoO3 and CoO. The hydrorefining catalyst intermediate is mixed with coke in a mass ratio of 20:1, and the calcination temperature is first increased to 400°C at a heating rate of 6°C / h under a nitrogen environment and maintained at this temperature for 3 hours; then the calcination temperature is increased to 600°C at a rate of 4°C / h and maintained at this temperature. When the mass loss of the hydrorefining catalyst intermediate is 85wt% of the amount of coke added, the calcination temperature is rapidly reduced and the calcination is stopped to obtain a hydrorefining catalyst powder. 3 wt% (relative to the weight of the hydrorefining catalyst powder) of binder sesbania powder was added to the powder, and a shaped catalyst was obtained by extrusion. The shaped catalyst was dried at 80°C for 4 hours and calcined at 260°C for 4 hours to obtain a finished hydrorefining catalyst C-1.

[0044] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the C-1 catalyst was 10:1. The C-1 catalyst was loaded into a hydrotreating reactor and evaluated for 2500 h under the conditions shown in Table 3.

[0045] Example 2

[0046] The catalyst preparation method of this embodiment is as follows: using γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source, a solution of a certain concentration is prepared, and the carrier is impregnated by an equal volume co-impregnation method. After drying at 70°C for 6 hours, it is calcined at 420°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, the hydrorefining catalyst intermediate is obtained with an alumina content of 65%, a MoO3 content of 30wt%, and a CoO content of 5wt%, respectively, calculated as MoO3 and CoO. After the hydrorefining catalyst intermediate is mixed with coke in a mass ratio of 14:1, the calcination temperature is first increased to 420°C at a heating rate of 6°C / h under a nitrogen environment and kept at this temperature for 4 hours; then the calcination temperature is increased to 650°C at a heating rate of 4°C / h and kept at this temperature. When the mass loss of the hydrorefining catalyst intermediate is 80wt% of the amount of coke added, the calcination temperature is rapidly reduced and the calcination is stopped to obtain a hydrorefining catalyst powder. 4 wt% (relative to the weight of the hydrorefining catalyst powder) of binder sesbania powder was added to the powder, and a shaped catalyst was obtained by extrusion. The shaped catalyst was dried at 80°C for 4 hours and calcined at 270°C for 5 hours to obtain a finished hydrorefining catalyst C-2.

[0047] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the C-2 catalyst is 8:1. The C-2 catalyst was loaded into a hydrotreating reactor and an evaluation experiment was conducted for 2500 h according to the conditions in Table 3.

[0048] Example 3

[0049] The catalyst preparation method of this embodiment is as follows: using γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source, a solution of a certain concentration is prepared, and the carrier is impregnated by an equal volume co-impregnation method. After drying at 70°C for 6 hours, it is calcined at 420°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, the hydrorefining catalyst intermediate is obtained with an alumina content of 65%, a MoO3 content of 30wt%, and a CoO content of 5wt%, respectively, calculated as MoO3 and CoO. After the hydrorefining catalyst intermediate is mixed with coke in a mass ratio of 14:1, the calcination temperature is first increased to 420°C at a heating rate of 4°C / h under a nitrogen environment and kept at this temperature for 4 hours; then the calcination temperature is increased to 650°C at a heating rate of 7°C / h and kept at this temperature. When the mass loss of the hydrorefining catalyst intermediate is 80wt% of the amount of coke added, the calcination temperature is rapidly reduced and the calcination is stopped to obtain a hydrorefining catalyst powder. 4 wt% (relative to the weight of the hydrorefining catalyst powder) of binder sesbania powder was added to the powder, and a shaped catalyst was obtained by extrusion. The shaped catalyst was dried at 80°C for 4 hours and calcined at 270°C for 5 hours to obtain a finished hydrorefining catalyst C-3.

[0050] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the C-3 catalyst was 2:1. The C-3 catalyst was loaded into a hydrotreating reactor and evaluated for 2500 h under the conditions shown in Table 3.

[0051] Comparative Example 1

[0052] The catalyst preparation method of this comparative example is as follows: a solution of a certain concentration is prepared using a γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source. The catalyst carrier is impregnated by an equal volume co-impregnation method. After drying at 70°C for 6 hours, the catalyst carrier is calcined at 420°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, the catalyst intermediate is obtained, with an alumina content of 65%, a MoO content of 30% by weight, and a CoO content of 5% by weight, respectively, calculated as MoO3 and CoO. 4% by weight (relative to the weight of the hydrorefining catalyst intermediate) of sesbania powder as a binder is added to the intermediate, and the catalyst is extruded to obtain a shaped catalyst. The shaped catalyst is then dried at 80°C for 4 hours and calcined at 270°C for 5 hours to obtain a finished hydrorefining catalyst Cat-1.

[0053] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the Cat-1 catalyst was 1:5. The Cat-1 catalyst was loaded into a hydrotreating reactor and evaluated for 2500 h according to the conditions in Table 3.

[0054] Comparative Example 2

[0055] The catalyst preparation method of this comparative example is as follows: using γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source, a solution of a certain concentration is prepared, and the carrier is impregnated by an equal volume co-impregnation method. After drying at 70°C for 6 hours, it is calcined at 420°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, a hydrorefining catalyst intermediate having an alumina content of 65%, a MoO3 content of 30wt%, and a CoO content of 5wt% is obtained, respectively, in terms of MoO3 and CoO. After mixing the hydrorefining catalyst intermediate with coke in a mass ratio of 4:1, the calcination temperature is increased to 420°C at a constant temperature under a nitrogen environment at a heating rate of 4°C / h. When the mass loss of the hydrorefining catalyst intermediate is 80wt% of the amount of coke added, the calcination temperature is rapidly reduced and the calcination is stopped to obtain a hydrorefining catalyst powder. 4 wt% (relative to the weight of the hydrorefining catalyst powder) of binder sesbania powder was added to the powder, and a shaped catalyst was obtained by extrusion. The shaped catalyst was dried at 80° C. for 4 h and calcined at 270° C. for 5 h to obtain a finished hydrorefining catalyst Cat-2.

[0056] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the Cat-2 catalyst is 26:1. The Cat-2 catalyst was loaded into a hydrotreating reactor and evaluated for 2500 h according to the conditions in Table 3.

[0057] Comparative Example 3

[0058] The catalyst preparation method of this comparative example is as follows: using γ-alumina raw material as a carrier, ammonium molybdate hexahydrate as a molybdenum source, and cobalt nitrate hexahydrate as a cobalt source, a solution of a certain concentration is prepared, and the carrier is impregnated by an equal volume co-impregnation method. After drying at 70°C for 6 hours, it is calcined at 420°C for 4 hours. Based on the weight of the hydrorefining catalyst intermediate, a hydrorefining catalyst intermediate having an alumina content of 65%, a MoO3 content of 30wt%, and a CoO content of 5wt% is obtained, respectively, in terms of MoO3 and CoO. After mixing the hydrorefining catalyst intermediate with coke in a mass ratio of 14:1, the hydrorefining catalyst intermediate is directly calcined at 420°C under a nitrogen environment. When the mass loss of the hydrorefining catalyst intermediate is 80wt% of the amount of coke added, the calcination temperature is rapidly reduced and the calcination is stopped to obtain a hydrorefining catalyst powder. 4 wt% (relative to the weight of the hydrorefining catalyst powder) of binder sesbania powder was added to the powder, and a shaped catalyst was obtained by extrusion. The shaped catalyst was dried at 80°C for 4 hours and calcined at 270°C for 5 hours to obtain a finished hydrorefining catalyst Cat-3.

[0059] The ratio of tetracoordinated Mo(Td) species to hexacoordinated Mo(Oh) species in the Cat-3 catalyst is 1:1. The Cat-3 catalyst was loaded into a hydrotreating reactor and an evaluation experiment was conducted for 2500 h according to the conditions in Table 3.

[0060] Table 1 Properties of crude oil

[0061] Raw oil name low-sulfur diesel <![CDATA[Density (20 °C) / g·cm -3 > 0.85 Distillation range / ℃ 200～350 S, ppm 600 N, ppm 1200

[0062] Table 2 Evaluation conditions

[0063] Reaction pressure, MPa 8.0 <![CDATA[Refining agent volume space velocity, h -1 > 1.0 Diesel sulfur content, ppm 10 Hydrogen-to-oil ratio at the inlet of hydrotreating reactor 400:1 Running time, h 2500

[0064] Table 3 Example test results

[0065] project Example 1 Example 2 Example 3 Hydrogen consumption, wt% 0.72 0.75 0.78 Refined catalyst deactivation rate, ℃ / d 0.030 0.033 0.036

[0066] Table 4 Comparative Example Test Results

[0067] project Comparative Example 1 Comparative Example 2 Comparative Example 3 Hydrogen consumption, wt% 0.89 0.85 0.82 Refined catalyst deactivation rate, ℃ / d 0.053 0.050 0.045

[0068] It can be seen from the experimental results of the comparative examples and the embodiments that, under the condition of controlling the same diesel sulfur content at 10 ppm, the hydrogen consumption of the hydrorefining catalyst of the present invention is low and the catalyst deactivation rate is slow.

Claims

1. A hydrorefining catalyst comprising a support and an active metal, wherein the active metal is selected from a Group VIB metal and a Group VIII metal, and wherein the ratio of the tetracoordinated Group VIB metal species to the hexacoordinated Group VIB metal species in the catalyst is 20:1 to 2:1 on an atomic basis. The content of Group VIB metal in the form of oxide is 8% to 47% based on the weight of the hydrorefining catalyst; The hydrotreating catalyst further comprises an additive, wherein the additive is carbon, and the carbon is derived from at least one of coke and graphite; The hydrotreating catalyst is prepared by the following method, which comprises: (1) impregnating a support raw material with a solution containing an active metal precursor, followed by drying and calcining to obtain a hydrorefining catalyst intermediate; (2) mixing the hydrorefining catalyst intermediate obtained in step (1) with the additive component, and calcining under inert gas. When the mass loss of the hydrorefining catalyst intermediate is 60% to 100% of the amount of the additive component added, cooling and stopping the calcination to obtain a hydrorefining catalyst powder; (3) The hydrorefining catalyst powder is mixed with a binder, molded, dried, and calcined to obtain a hydrorefining catalyst.

2. The hydrotreating catalyst according to claim 1, characterized in that In the catalyst, the ratio of the tetracoordinated VIB Group metal species to the hexacoordinated VIB Group metal species is 15:1 to 4:1 in terms of atoms.

3. The hydrotreating catalyst according to claim 1, characterized in that The hydrotreating catalyst further comprises a binder, which is derived from aluminum sol.

4. The hydrotreating catalyst according to claim 1, characterized in that The Group VIB metal is selected from W and / or Mo, and the Group VIII metal is selected from Co and / or Ni.

5. The hydrotreating catalyst according to claim 1, characterized in that The carrier is selected from alumina, and the crystal form of the alumina includes at least one of α-alumina, β-alumina, γ-alumina, δ-alumina, θ-alumina, and η-alumina.

6. The hydrotreating catalyst according to claim 5, characterized in that The carrier is selected from alumina, and the crystal form of the alumina is γ-alumina and / or η-alumina.

7. The hydrotreating catalyst according to any one of claims 1 to 6, characterized in that Based on the weight of the hydrorefining catalyst, the content of the carrier is 50% to 80%, the content of the active metal in terms of oxide is 20% to 50%, and the content of the Group VIII metal in terms of oxide is 3% to 12%.

8. The hydrotreating catalyst according to claim 7, characterized in that Based on the weight of the hydrorefining catalyst, the content of the carrier is 55% to 75%, the content of the active metal in terms of oxide is 25% to 44%, of which the content of the Group VIII metal in terms of oxide is 4% to 10%, and the content of the Group VIB metal in terms of oxide is 15% to 40%.

9. The method for preparing the hydrotreating catalyst according to any one of claims 1 to 8, comprising: (1) impregnating a support raw material with a solution containing an active metal precursor, followed by drying and calcining to obtain a hydrorefining catalyst intermediate; (2) mixing the hydrorefining catalyst intermediate obtained in step (1) with the additive component, and calcining under inert gas. When the mass loss of the hydrorefining catalyst intermediate is 60% to 100% of the amount of the additive component added, cooling and stopping the calcination to obtain a hydrorefining catalyst powder; (3) The hydrorefining catalyst powder is mixed with a binder, molded, dried, and calcined to obtain a hydrorefining catalyst.

10. The preparation method according to claim 9, characterized in that In step (2), the hydrorefining catalyst intermediate obtained in step (1) is mixed with the additive component and calcined under inert gas. When the mass loss of the hydrorefining catalyst intermediate is 70% to 95% of the amount of the additive component added, the temperature is lowered and the calcination is stopped to obtain a hydrorefining catalyst powder.

11. The preparation method according to claim 9, characterized in that In step (1), the drying temperature is 60-120° C., the drying time is 4-12 h, and / or the roasting temperature is 200-700° C., the roasting time is 2-12 h.

12. The preparation method according to claim 11, characterized in that In step (1), the drying temperature is 70-100° C., the drying time is 6-10 h, and / or the roasting temperature is 300-600° C., the roasting time is 4-6 h.

13. The preparation method according to claim 9, characterized in that In step (2), the mass ratio of the hydrorefining catalyst intermediate to the additive component is 40:1 to 5:

1.

14. The preparation method according to claim 13, characterized in that In step (2), the mass ratio of the hydrorefining catalyst intermediate to the additive component is 30:1 to 10:

1.

15. The preparation method according to claim 9, characterized in that In step (2), the inert gas is at least one of nitrogen, helium, and argon, and the calcination temperature is 300-800°C.

16. The preparation method according to claim 9, characterized in that In step (2), the roasting is carried out in two stages. The roasting conditions of the first stage are: the roasting temperature is increased from room temperature to 300-450°C at a rate of 3-12°C / h, and the first constant temperature is performed for 2-6 hours; the roasting conditions of the second stage are: the roasting temperature is further increased to 460-800°C at a rate of 2-7°C / h, and the second constant temperature is performed. The second constant temperature time is determined according to the mass loss of the hydrorefining catalyst intermediate.

17. The preparation method according to claim 16, characterized in that In step (2), the roasting is carried out in two stages. In the first stage, the roasting temperature is increased from room temperature to 300-450°C at a rate of 5-10°C / h, and the first constant temperature is performed. In the second stage, the roasting temperature is further increased to 460-800°C at a rate of 2-5°C / h, and the second constant temperature is performed.

18. The preparation method according to claim 9, characterized in that In step (3), the drying temperature is 50-100°C, the drying time is 4-24 hours, and / or the roasting temperature is 200-400°C, and the roasting time is 2-10 hours.

19. The preparation method according to claim 18, characterized in that In step (3), the drying temperature is 60-80°C, the drying time is 6-10 hours, and / or the roasting temperature is 250-350°C, and the roasting time is 4-8 hours.

20. Use of the hydrotreating catalyst according to any one of claims 1 to 8 in a diesel hydrotreating process.

21. The use according to claim 20, characterized in that The raw material for the hydrorefining process is a low-sulfur, high-nitrogen diesel raw material, wherein the low-sulfur, high-nitrogen diesel raw material has a sulfur content of 100-1000 ppm and a nitrogen content of 200-1400 ppm by mass.

22. The use according to claim 21, characterized in that The raw material for the hydrorefining process is a low-sulfur, high-nitrogen diesel raw material, wherein the low-sulfur, high-nitrogen diesel raw material has a sulfur content of 200-800 ppm and a nitrogen content of 300-1200 ppm by mass.

23. The use according to claim 20, characterized in that In the hydrofining process, the reaction conditions of the refining reactor are: reaction pressure of 4.0-14.0 MPa, reaction temperature of 300-440°C, volume space velocity of 0.5-4.0 h -1 .

24. The use according to claim 23, characterized in that In the hydrofining process, the reaction conditions of the refining reactor are: reaction pressure of 6.0-8.0 MPa, reaction temperature of 320-420°C, volume space velocity of 1.0-2.0 h -1 .