A hydrodemeshing catalyst and its preparation method

Abstract

The present invention discloses a hydrodecarbonization catalyst and its preparation method. The catalyst comprises a catalyst body, a catalyst sub-outer layer, and a macroporous alumina layer. The catalyst body comprises an alumina carrier and active components, molybdenum and nickel. Based on the mass of the catalyst body, the molybdenum oxide content is 8.00% to 24.00%, and the nickel oxide content is 2.00% to 6.00%. Based on the mass of the catalyst sub-outer layer, the molybdenum oxide content is 2.00% to 12.00%, and the nickel oxide content is 0.50% to 3.50%. The hydrodecarbonization catalyst provided by the present invention not only has excellent hydrodecarbonization performance, but also has good metal and carbon storage capacity, providing the necessary conditions for long-term operation of the device.

Description

Technical Field

[0001] The invention relates to a hydrogenation carbon residue removal catalyst and a preparation method thereof. Background Art

[0002] As oil resources continue to degrade and become heavier, market demand for diversified and lighter petrochemical products is increasing. Processing low-quality, heavy crude oil has become a critical challenge for refining companies worldwide. Fixed-bed residue hydrotreating technology has become a key method for converting low-quality, heavy crude oil to lighter products. Combined with heavy oil catalytic cracking, it can convert heavy oil into high-value, light oil products, achieving efficient conversion and utilization of residue oil. The primary purpose of fixed-bed residue hydrotreating technology is to remove impurities such as sulfur, nitrogen, and metals from the residue oil and reduce the carbon residue, thereby providing qualified, high-quality feed for the catalytic cracking unit.

[0003] Residue hydroremoval of carbon residue is the process of removing precursors to carbon residue. Residue carbon residue precursors are primarily composed of larger polycyclic aromatic hydrocarbons within the asphaltenes or resins. To enhance a catalyst's ability to remove carbon residue during hydroremoval, its hydrogenation and hydroconversion capabilities for these substances must be enhanced. When improving a catalyst's hydroconversion capabilities, the principle of activity stability should be prioritized; that is, activity improvement should not be achieved at the expense of stability.

[0004] CN201210427641.6 discloses a hydrogenation carbon removal catalyst, which uses alumina as a carrier and Mo and Ni as active components. The catalyst contains 10% to 20% MoO3 and 2% to 5% NiO by weight. The surface area of the catalyst is 150 to 210 m 2 / g, preferably 160-190m 2 / g; the pore volume is 0.5-0.90 mL / g, preferably 0.6-0.80 mL / g. CN201510724477.9 discloses a hydrogenation carbon removal catalyst comprising an active metal component and a modified hydrogenation catalyst support. The modified hydrogenation catalyst support is prepared by the following method: repeatedly impregnating and drying a hydrothermally treated support, and calcining the dried product obtained at the last step. CN201910326569.X discloses a method for preparing a hydrogenation carbon removal catalyst, comprising the following steps: (1) mixing a pore-enlarging agent with pseudo-boehmite to obtain a mixture A; (2) mixing metakaolin, ammonium bicarbonate, and water, sealing and crystallizing the mixture, drying and calcining the crystallized material, and subjecting the material to dealuminization, and drying to obtain material B; (3) subjecting mixture A to ball forming to obtain a precursor I; (4) mixing material B with precursor I, ball forming the mixture, drying and calcining the mixture, and then loading the active component to obtain a hydrogenation carbon removal catalyst. The surfaces of the catalysts prepared by the above methods are all loaded with active metals, and the hydrogenation reaction on the catalyst surface is relatively intense. The generated carbon deposits and metal deposits easily clog the pores and cover the hydrogenation active sites, which is not conducive to the long-term operation of the device. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention provides a hydrogenation carbon removal catalyst and its preparation method. This catalyst integrates three functions: resisting carbon deposition, removing metals, and removing carbon residue. It not only exhibits excellent hydrogenation carbon removal performance but also provides the necessary conditions for long-term operation of the device.

[0006] The first aspect of the present invention provides a hydroremoval of carbon residue catalyst, comprising a catalyst body, a catalyst sub-outer layer and a macroporous alumina layer, wherein the catalyst body comprises an alumina carrier and an active component, and the catalyst sub-outer layer comprises macroporous alumina and an active component; the active component comprises molybdenum and nickel, and the molybdenum oxide content in the catalyst body is 8.00% to 24.00%, and the nickel oxide content is 2.00% to 6.00%, based on the mass of the catalyst body; the molybdenum oxide content in the catalyst sub-outer layer is 2.00% to 12.00%, and the nickel oxide content is 0.50% to 3.50%, based on the mass of the catalyst sub-outer layer; the thickness of the macroporous alumina layer is 80 to 160 μm, preferably 105 to 120 μm.

[0007] In the present invention, the pore volume of the macroporous alumina layer is 0.80 to 1.15 cm 3 / g, with a specific surface area of 150 to 280 m 2 / g.

[0008] In the present invention, the pore volume of the secondary outer layer is 0.70 to 1.15 cm 3 / g (mercury intrusion method), specific surface area is 120~260m 2 / g.

[0009] In the present invention, the carrier in the catalyst body is an alumina-based carrier, and the pore volume of the carrier is 0.60 to 0.95 cm 3 / g, preferably 0.65 to 0.85 cm 3 / g, with a specific surface area of 270 to 360 m 2 / g.

[0010] In the present invention, the catalyst further contains auxiliary phosphorus, with the phosphorus content being 0.80% to 2.50% based on the mass of the catalyst body and 0.20% to 1.20% based on the mass of the sub-outer layer of the catalyst.

[0011] In the present invention, the mass ratio of the catalyst sub-outer layer to the catalyst body is 2.41×10 -9 :1~4.86×10 -6 :1.

[0012] The second aspect of the present invention provides a method for preparing the above-mentioned hydrogenation carbon residue removal catalyst, comprising the following steps:

[0013] (1) impregnating a support with a microemulsion containing an active component and drying the support to obtain a catalyst body;

[0014] (2) preparing macroporous pseudo-boehmite slurry;

[0015] (3) mixing the macroporous pseudo-boehmite slurry obtained in step (2) with a solution containing an active component in proportion to obtain a mixed solution;

[0016] (4) spraying the catalyst body obtained in step (1) with the mixed solution obtained in step (3), and drying to obtain a catalyst intermediate (second outer layer);

[0017] (5) adding the catalyst intermediate of step (4) into the macroporous pseudo-boehmite slurry obtained in step (2) and stirring and soaking the mixture; taking the mixture out after the surface is coated with gel, drying it, and calcining it to obtain the hydrogenation carbon removal catalyst.

[0018] In the method of the present invention, the microemulsion containing the active ingredient in step (1) is prepared by mixing a solution containing the active ingredient with an emulsifier. The active ingredient solution is a molybdenum-nickel-phosphorus solution, wherein the active metal molybdenum is derived from at least one of molybdenum oxide, ammonium molybdate, and molybdenum nitrate; the nickel is derived from at least one of basic nickel carbonate, nickel carbonate, nickel nitrate, and nickel sulfate; and the phosphorus is derived from at least one of phosphoric acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, ammonium phosphate, or a mixture thereof. The content of molybdenum oxide in the solution is 10.00 to 45.00 g / 100 mL, the content of nickel oxide is 2.50 to 12.00 g / 100 mL, and the content of phosphorus is 1.00 to 4.50 g / 100 mL.

[0019] In the method of the present invention, in step (1), the emulsifier is a nonionic emulsifier, preferably selected from one or more of polyoxyethylene ether, polyoxypropylene ether, ethylene oxide-propylene oxide block copolymer, polyoxyethylene ester, polyol fatty acid ester, polyvinyl alcohol, polysorbate 60, and polysorbate 80, preferably polysorbate 60 or polysorbate 80. The amount of the emulsifier added is 1% to 20% of the volume of the solution containing the active ingredient in step (1), preferably 2% to 6%.

[0020] In the method of the present invention, in step (1), the carrier is impregnated with the microemulsion containing the active ingredient. The impregnation method can be a saturated impregnation method or a supersaturated impregnation method. Preferably, the amount of the microemulsion containing the active ingredient is 100% to 130% of the saturated water absorption capacity of the carrier, and the impregnation time is 2 to 6 hours. Preferably, after impregnation, the carrier is allowed to stand at 30 to 80°C for 2 to 10 hours, and then dried at 100 to 180°C for 3 to 10 hours.

[0021] In the method of the present invention, the method for preparing the macroporous pseudo-boehmite slurry in step (2) comprises:

[0022] a) neutralizing an acidic aluminum salt solution and an alkaline aluminum salt solution to obtain a slurry;

[0023] b) subjecting the slurry obtained in step a) to a first stage of aging; after the first stage of aging, adding a water-soluble polymer A and subjecting the slurry to a second stage of aging;

[0024] c) filtering and washing the material after the second aging stage in step b), and then adding water to slurry to obtain the macroporous pseudo-boehmite slurry.

[0025] In the method of the present invention, in step a), the acidic aluminum salt solution and the alkaline aluminum salt solution are added to the reactor in parallel, and the addition time is 40 to 120 minutes.

[0026] In the method of the present invention, in step a), the acidic aluminum salt is selected from one or more of aluminum sulfate and aluminum nitrate solutions; the concentration of the acidic aluminum salt solution is 5g / 100mL to 18g / 100mL in terms of Al2O3.

[0027] In the method of the present invention, the alkaline aluminum salt solution in step a) is one or more of sodium metaaluminate solution and potassium metaaluminate solution; the concentration of the alkaline aluminum salt solution in terms of Al2O3 is 15g / 100mL to 45g / 100mL.

[0028] In the method of the present invention, the neutralization reaction in step a) is carried out at a temperature of 80 to 105° C. for 40 to 120 minutes, and the pH of the slurry is controlled to be 7.0 to 9.0 during the neutralization reaction. The pH of the slurry is controlled during the neutralization reaction by controlling the amount of the acidic aluminum salt solution and the alkaline aluminum salt solution added or by adding an additional acid-base modifier.

[0029] In the method of the present invention, the temperature of the first stage aging in step b) is 140-250° C., the time is 60-200 min, and the pH value is 9.0-11.0.

[0030] In the method of the present invention, the water-soluble polymer A in step b) is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylamide and methyl cellulose.

[0031] In the method of the present invention, the amount of water-soluble polymer A added in step b) is such that the concentration of the water-soluble polymer A in the system after addition is 1 to 10 g / 100 mL and the viscosity of the system after addition of the water-soluble polymer A (at 20° C.) is 100 to 500 mPa·s.

[0032] In the method of the present invention, after the first stage aging in step b) is completed, the slurry is preferably concentrated so that the volume after concentration is 40% to 70% of the original volume.

[0033] In the method of the present invention, the temperature of the second stage aging in step b) is 160-300° C., and the time is 45-200 minutes. The temperature of the second stage aging is higher than the temperature of the first stage aging, preferably 20-50° C. higher.

[0034] In the method of the present invention, the filtering, washing and beating in step c) are conventional technical means in the art.

[0035] In the method of the present invention, the alumina content in the macroporous pseudo-boehmite slurry in step c) is 5 to 300 g / L.

[0036] In the method of the present invention, the solution containing the active component in step (3) is a molybdenum-nickel-phosphorus solution, wherein the active metal molybdenum is derived from at least one of molybdenum oxide, ammonium molybdate, and molybdenum nitrate, the nickel is derived from at least one of basic nickel carbonate, nickel carbonate, nickel nitrate, and nickel sulfate, and the phosphorus is derived from at least one of phosphoric acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, ammonium phosphate, or a mixture thereof. The content of molybdenum oxide in the solution is 10.00 to 45.00 g / 100 mL, the content of nickel oxide is 2.50 to 12.00 g / 100 mL, and the content of phosphorus is 1.00 to 4.50 g / 100 mL. After the macroporous pseudo-boehmite slurry is mixed with the solution containing the active component, the mass of the molybdenum oxide in the mixed solution accounts for 2.00% to 12.00% of the total mass of the oxides in the mixed solution, and the mass of the nickel oxide accounts for 0.50% to 3.50% of the total mass of the oxides in the mixed solution.

[0037] In the method of the present invention, the macroporous pseudo-boehmite slurry is concentrated or diluted before mixing in step (3) to control the alumina content therein to be 5-300 g / L.

[0038] In the method of the present invention, the impregnation in step (4) adopts unsaturated impregnation, and the amount of the mixed liquid is 1% to 20% of the saturated water absorption rate of the carrier. The drying conditions are: drying at 100 to 160° C. for 2 to 12 hours.

[0039] In the method of the present invention, the soaking time in step (5) is 3 seconds to 20 minutes. After the surface is coated with the macroporous pseudo-boehmite slurry, the slurry is removed and centrifuged for 1 to 20 minutes to remove excess surface solution. The slurry is then dried at 100 to 160°C for 2 to 12 hours. The calcination conditions are: calcination at 450 to 600°C for 2 to 6 hours. The calcination is carried out in an oxygen-containing atmosphere.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The present invention prepares a hydrogenation decarbonization catalyst, and the active metal of the catalyst is unevenly distributed. The outermost layer of the catalyst does not contain active metals, and is a layer of macroporous alumina, which has high volumetric carbon and metal storage capacity. The sub-outer layer of the catalyst contains less active metal and has larger pores, has better demetallization and metal storage performance, and has the function of a demetallization catalyst. During the preparation process of the catalyst body, a microemulsion containing active metals is impregnated to adjust the catalyst body to have suitable acidic properties. The hydrogenation decarbonization catalyst prepared by the present invention is a catalyst that integrates three functions of anti-carbon deposition, demetallization, metal storage, and carbon removal. It not only has good hydrogenation decarbonization performance, but also has good metal storage and carbon storage capacity, which provides the necessary conditions for the long-term operation of the device. DETAILED DESCRIPTION

[0042] The following examples further illustrate the technical solutions and effects of the present invention. The examples are implemented based on the technical solutions of the present invention, and provide detailed implementation methods and specific operating processes, but the scope of protection of the present invention is not limited to the following examples.

[0043] In the examples and comparative examples of the present invention, the pore volume (mercury intrusion) of the macroporous alumina in the sub-outer layer and outer surface of the catalysts was measured using a Quantachrome PoreMaster 60GT mercury intrusion instrument. The specific surface area of the macroporous alumina in the sub-outer layer and outer surface of the catalysts in the examples and comparative examples was measured using a Micromeritics TriStar 2420 physical adsorption analyzer.

[0044] In the present invention, the metal element contents in the solutions and catalysts in the examples and comparative examples are analyzed using an inorganic method.

[0045] Example 1

[0046] Take the alumina support (the pore volume of the support is 0.72cm 3 / g, with a specific surface area of 296m 2 A molybdenum-nickel-phosphorus solution was prepared, containing 24.8 g of MoO3, 6.1 g of NiO, and 2.5 g of P per 100 ml. 180 ml of the molybdenum-nickel-phosphorus solution was added to 6 g of polysorbate 80 to prepare a microemulsion containing the active components. The alumina support was saturated with the microemulsion and then cured at 50°C for 3 hours and dried at 120°C for 3 hours to obtain the catalyst body.

[0047] 2L of aluminum sulfate aqueous solution (concentration of 11.3g / 100mL based on Al2O3, initial temperature of 85°C) was introduced from the top into a reactor equipped with 5L of purified water, a stirrer and a heating jacket, and 1.5L of sodium metaaluminate aqueous solution (concentration of 31.5g / 100mL based on Al2O3, initial temperature of 85°C) was introduced from the bottom of the reactor into the reactor. The neutralization reaction temperature was controlled at 95°C. Aluminum sulfate solution and sodium metaaluminate solution were added continuously, and the pH was controlled. The value was 8.4 and stabilized for 50 minutes; after the parallel flow was completed, the first stage of aging was carried out, the aging temperature was 140°C, the aging time was 120 minutes, and the aging pH value was 9.2; after the first stage of aging was completed, the slurry volume was concentrated to 5L, 100g of polyvinyl alcohol was added, and the slurry viscosity (20°C) was 325mPa·s, the temperature was raised to 170°C, and the second stage of aging was carried out for 120 minutes, washed, filtered, and slurried with clean water to obtain a macroporous pseudo-boehmite slurry.

[0048] A macroporous pseudo-boehmite slurry (alumina content of 100 g / L) was mixed with an active metal solution such that the mass of molybdenum oxide in the mixture accounted for 8.40% of the total mass of the oxides in the mixture, and the mass of nickel oxide accounted for 2.06% of the total mass of the oxides in the mixture. The catalyst body was spray-impregnated with a mixture amounting to 3.3% of the carrier's saturated water absorption rate. After spraying, the catalyst body was dried at 120°C for 3 hours. The catalyst body was then added to a macroporous pseudo-boehmite slurry (alumina content of 32 g / L), stirred and immersed for 1 minute. After the surface was coated with the slurry, the catalyst body was removed, centrifuged in a high-speed centrifuge for 5 minutes, and dried at 110°C for 5 hours. The catalyst body was then calcined at a heating rate of 2°C / min to 500°C for 4 hours to obtain Hydrocarbon Removal Catalyst A.

[0049] Example 2

[0050] The same method as Example 1, except that in step (1), 180 ml of the molybdenum-nickel-phosphorus solution was added with 4 g of polysorbate 60 to prepare a microemulsion containing the active component. This was used to prepare a hydrogenation carbon removal catalyst B.

[0051] Example 3

[0052] The same as Example 1, except that in step (3), the mass of molybdenum oxide in the mixed solution accounts for 6.27% of the total mass of the oxides in the mixture, and the mass of nickel oxide accounts for 1.54% of the total mass of the oxides in the mixed solution, thus obtaining hydrogenation and carbon residue removal catalyst C.

[0053] Example 4

[0054] The same as Example 1, except that in step (4), after the macroporous pseudo-boehmite slurry is mixed with the molybdenum nickel phosphorus solution, the catalyst precursor is sprayed with the mixed solution at an amount of 10% of the saturated water absorption rate of the carrier to obtain the hydrogenation carbon residue removal catalyst D.

[0055] Example 5

[0056] The same as Example 1, except that in step (5), the catalyst was added to a macroporous pseudo-boehmite slurry (alumina content of 44 g / L), stirred, and then centrifuged in a high-speed centrifuge for 3 minutes to obtain a hydrogenation carbon removal catalyst E.

[0057] Comparative Example 1

[0058] The same as Example 1, except that the catalyst body obtained in step (1) was directly calcined at 500°C for 4 hours to obtain hydrogenation carbon removal catalyst F. The pore volume of catalyst F is 0.46 cm 3 / g, specific surface area of 185m 2 / g, the mass content of MoO3 is 16.75%, the mass content of NiO is 4.09%, and the mass content of P is 1.67%.

[0059] Comparative Example 2

[0060] The same as Example 1, except that in step (3), the mass of molybdenum oxide in the mixed solution accounts for 16.75% of the total mass of the oxides in the mixture, and the mass of nickel oxide accounts for 4.09% of the total mass of the oxides in the mixed solution, thus obtaining hydrogenation and carbon residue removal catalyst G.

[0061] Table 1 Physicochemical properties of the catalysts obtained in each case

[0062]

[0063]

[0064] Evaluation test

[0065] The activity and stability of catalysts AG were evaluated in a 200 ml fixed-bed hydrogenation test apparatus. The properties of the feed oil are listed in Table 2, the experimental conditions are listed in Table 3, and the experimental results are listed in Table 4.

[0066] Table 2 Properties of crude oil

[0067] project content S, wt% 3.93 Ni+V, μg / g 95.8 CCR, wt% 12.48

[0068] Table 3 Evaluation experimental process conditions

[0069] Reaction temperature, °C 385 Reaction pressure, MPa 15.0 <![CDATA[Space velocity, h- 1 > 0.5 Hydrogen-to-oil volume ratio 700

[0070] Table 4 lists the removal rates obtained after operation of the feedstock oils in Table 2 using the catalysts obtained in Examples 1-5 and Comparative Examples 1-2 under the process conditions in Table 3.

[0071] Table 4 Removal rate after operation

[0072]

[0073] Table 4 Removal rate after operation (continued)

[0074]

[0075] Table 4 Removal rate after operation (continued)

[0076]

[0077] As can be seen from Table 4, the hydrogenation carbon removal catalyst prepared in the present invention has better carbon removal performance than the comparative agent, and has higher demetallization performance, and also has better desulfurization performance, integrating the demetallization, desulfurization and carbon removal functions, and has good removal stability, providing technical support for extending the operation cycle of the device.

Claims

1. A hydroremoval of carbon residue catalyst, comprising a catalyst body, a catalyst sub-outer layer, and a macroporous alumina layer, wherein the catalyst body comprises an alumina carrier and an active component, the catalyst sub-outer layer comprises macroporous alumina and an active component, the active component comprising molybdenum and nickel, the catalyst body having a molybdenum oxide content of 8.00% to 24.00% and a nickel oxide content of 2.00% to 6.00% based on the mass of the catalyst body, the catalyst sub-outer layer having a molybdenum oxide content of 2.00% to 12.00% and a nickel oxide content of 0.50% to 3.50% based on the mass of the catalyst sub-outer layer, and the macroporous alumina layer having a thickness of 80 to 160 μm; The mass ratio of the catalyst sub-outer layer to the catalyst body is 2.41 × 10 -9 :1~4.86 ×10 -6 :1; The pore volume of the macroporous alumina layer is 0.80-1.15 cm 3 / g; The pore volume of the secondary outer layer is 0.70~1.15cm 3 / g.

2. The catalyst according to claim 1, characterized in that The thickness of the macroporous alumina layer is 105-120 μm.

3. The catalyst according to claim 1, characterized in that The specific surface area of the macroporous alumina layer is 150-280 m 2 / g.

4. The catalyst according to claim 1, characterized in that The carrier in the catalyst body is an alumina-based carrier, and the pore volume of the carrier is 0.60~0.95cm 3 / g, with a specific surface area of 270~360m 2 / g.

5. The catalyst according to claim 4, characterized in that The pore volume of the carrier is 0.65~0.85 cm 3 / g.

6. The catalyst according to claim 1, characterized in that The catalyst also contains auxiliary phosphorus. Based on the mass of the catalyst body, the phosphorus content in the catalyst body is 0.80%-2.50%, and based on the mass of the catalyst sub-outer layer, the phosphorus content in the catalyst sub-outer layer is 0.20%-1.20%.

7. A method for preparing the catalyst according to any one of claims 1 to 6, comprising the steps of: (1) impregnating the support with a microemulsion containing the active component and drying to obtain the catalyst body; (2) Preparation of macroporous pseudo-boehmite slurry; (3) mixing the macroporous pseudo-boehmite slurry obtained in step (2) with a solution containing an active component in proportion to obtain a mixed solution; (4) Spraying the catalyst body obtained in step (1) with the mixed solution obtained in step (3), and drying to obtain a catalyst intermediate; (5) The catalyst intermediate of step (4) is added to the macroporous pseudo-boehmite slurry obtained in step (2), stirred and immersed, and after the surface is coated with gel, taken out, dried, and calcined to obtain the hydrogenation carbon removal catalyst.

8. The method according to claim 7, characterized in that The microemulsion containing the active component in step (1) is prepared by mixing a solution containing the active component with an emulsifier, wherein the content of molybdenum oxide in the solution containing the active component is 10.00-45.00 g / 100 mL, the content of nickel oxide is 2.50-12.00 g / 100 mL, and the content of phosphorus is 1.00-4.50 g / 100 mL.

9. The method according to claim 8, characterized in that The emulsifier is a nonionic emulsifier; the amount of the emulsifier added is 1% to 20% of the volume of the solution containing the active ingredient in step (1).

10. The method according to claim 9, characterized in that The emulsifier is selected from one or more of polyoxyethylene ether, polyoxypropylene ether, ethylene oxide-propylene oxide block copolymer, polyoxyethylene ester, polyol fatty acid ester, polyvinyl alcohol, polysorbate 60, and polysorbate 80; the amount of the emulsifier added is 2% to 6% of the volume of the solution containing the active component in step (1).

11. The method according to claim 7, characterized in that The amount of the microemulsion containing the active ingredient in step (1) is 100% to 130% of the saturated water absorption capacity of the carrier, and the immersion time is 2 to 6 hours.

12. The method according to claim 11, characterized in that After the impregnation in step (1), the mixture is allowed to stand at 30-80°C for 2-10 hours, and then dried at 100-180°C for 3-10 hours.

13. The method according to claim 7, characterized in that The method for preparing the macroporous pseudo-boehmite slurry in step (2) comprises: a) neutralizing an acidic aluminum salt solution and an alkaline aluminum salt solution to obtain a slurry; b) subjecting the slurry obtained in step a) to a first-stage aging; after the first-stage aging, adding water-soluble polymer A and subjecting the slurry to a second-stage aging; c) filtering and washing the material after the second aging stage in step b), and then adding water to slurry to obtain the macroporous pseudo-boehmite slurry.

14. The method according to claim 7, wherein: In step (3), the macroporous pseudo-boehmite slurry is concentrated or diluted before mixing to control the alumina content therein to 5-300 g / L.

15. The method according to claim 7, characterized in that The mass of molybdenum oxide in the mixed solution in step (3) accounts for 2.00% to 12.00% of the total mass of oxides in the mixed solution, and the mass of nickel oxide accounts for 0.50% to 3.50% of the total mass of oxides in the mixed solution.

16. The method according to claim 7, characterized in that The amount of the mixed solution used in step (4) is 1% to 20% of the saturated water absorption rate of the carrier.

17. The method according to claim 7, characterized in that In step (5), the immersion time is 3s~20min, and the surface is taken out after being coated with the macroporous pseudo-boehmite slurry. The excess solution on the surface is removed by centrifugation for 1~20min, and then dried at 100~160℃ for 2~12 hours.

18. The method according to claim 7, characterized in that The calcination conditions in step (5) are: calcination at 450-600° C. for 2-6 hours, and the calcination is carried out in an oxygen-containing atmosphere.

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