Alumina support, hydrogenation catalyst and preparation method and application thereof

Abstract

The application discloses an alumina carrier, a hydrogenation catalyst and a preparation method thereof. The alumina carrier is a mixed phase of gamma-Al2O3 and AlOOH, wherein the AlOOH is in-situ directionally grown on the outer surface of the alumina carrier, and the AlOOH crystal grain morphology is a flaky structure, and the crystal grain size is 100-600 nm. The preparation method of the alumina carrier comprises the following contents: (1) uniformly mixing pseudo-boehmite, a co-extrusion agent and a physical pore-expanding agent, adding a peptizing agent, and then performing kneading, drying and calcination to obtain an alumina carrier precursor; (2) sealing and heat-treating the alumina carrier precursor in a propylene oxide aqueous solution, performing solid-liquid separation on the treated material, and performing drying treatment on the solid-phase material to obtain the alumina carrier. The alumina carrier has flaky AlOOH crystal grains in-situ grown on the outer surface, open channels are formed between the flaky crystal grains, and the alumina carrier is firmly combined, so that the catalyst prepared by using the alumina carrier as a carrier has a wide application prospect in the field of heterogeneous catalysts.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of material synthesis, and particularly relates to an alumina carrier, a hydrodemetallization catalyst and a preparation method and application thereof. BACKGROUND

[0002] With the increasingly stringent environmental regulations and the increasing degree of crude oil heaviness, efficient conversion of heavy oil has become an important trend in the development of oil refining technology. Fixed-bed residual oil hydrogenation technology is an effective means to achieve efficient conversion of heavy oil. However, due to the complex molecular composition, high viscosity and high impurity content of residual oil, the hydrogenation reaction is difficult, and it is required to effectively remove the metal, sulfur, nitrogen and carbon residue impurities in the residual oil through catalytic reaction. A single catalyst cannot meet the requirements, and it is necessary to use catalysts with different functions, shapes and sizes to match the loading system to achieve high activity and long-period operation in industrial effect. Residual oil hydroprocessing catalysts usually include protective catalysts, demetallization catalysts, desulfurization catalysts and denitrification catalysts, each of which has other functions. Residual oil hydrodemetallization catalyst is one of the main catalysts in residual oil hydroprocessing technology, which plays a role in removing Ni, V and other metals in residual oil, and also protects the desulfurization catalyst. It not only removes metal impurities in the feedstock, but also must accommodate as much metal and coke impurities as possible.

[0003] CN114425374A discloses a residual oil hydrodemetallization catalyst and a preparation method thereof. The catalyst includes a catalyst body composed of a carrier and an active component supported on the carrier, and has a carbon film on the outer surface of the catalyst body. The carbon film covers the surface active center, so that during the residual oil hydrogenation process, the carbon deposition, sulfide and iron, calcium and other deposits produced after the intense reaction of the residual oil on the catalyst surface active site are prevented from blocking the catalyst pores and covering the active sites, and the catalyst has good anti-coking performance. However, the hydrogenation demetallization catalyst prepared by the method has small surface pores, which is not conducive to the diffusion of residual oil reactant molecules to the inside of the catalyst.

[0004] CN104646008A discloses a poor-quality heavy oil hydrodesulfurization and demetallization catalyst and a preparation method thereof. The catalyst uses alumina as the carrier, and uses Group VIII and Group VIB elements, especially Ni-Mo, as the active component. The catalyst has a pore volume of 0.61-0.70 mL / g, a specific surface area of 155-200 m 2 / g, and an average pore diameter of 13.0-18.0 nm. The preparation method of the catalyst is to treat the carrier particles after molding and calcination with an acid solution with continuously increasing concentration, so as to improve the pore structure of the carrier and the hydrogen demetallization catalyst. This method needs to be further improved to increase the content of large pores of the alumina carrier, especially the large pores on the surface.

[0005] CN110935461A discloses a preparation method of a heavy oil hydrodemetallization catalyst. The preparation method of the catalyst comprises: (1) mixing and kneading a physical pore expander, pseudo-boehmite and an active metal component, drying and calcining to obtain a modified alumina carrier SI; (2) unsaturatedly spraying and impregnating SI with a hydrogenation active component impregnation solution I, and then drying and calcining to obtain a modified alumina carrier SII; (3) mixing SII, ammonium bicarbonate and water, and then performing sealed heat treatment, and then drying and calcining the material after heat treatment to obtain a carrier SIII; (4) supersaturatedly impregnating the carrier SIII with a hydrogenation active component impregnation solution II, and then drying and calcining to obtain the catalyst. The catalyst prepared by the method has a rod-shaped structure on the surface, the formed pore channel is open, the metal deposition resistance and the carbon deposition resistance of the catalyst are improved, but the rod-shaped alumina grown on the surface is easy to fall off, and the firmness of the combination with the main body alumina needs to be further improved. SUMMARY

[0006] In view of the deficiencies in the prior art, the present application provides an alumina carrier, a hydrodemetallization catalyst and a preparation method and application thereof. The alumina carrier prepared by the method has flaky AlOOH crystal grains grown in situ on the outer surface, and open channels are formed between the flaky crystal grains. The combination is firm. The hydrodemetallization catalyst prepared by using the alumina as the carrier has high demetallization activity and stability.

[0007] The first aspect of the present application provides an alumina carrier. The alumina carrier is a mixed phase of γ-Al2O3 and AlOOH, wherein AlOOH is grown in situ and oriented on the outer surface of the alumina carrier, the morphology of the AlOOH crystal grains is flaky structure, and the grain size is 100-600 nm; the ratio H of the grain size of the crystal face corresponding to the AlOOH (120) peak to the grain size of the crystal face corresponding to the γ-Al2O3 (440) peak is 3.5-5.0, H=D AlOOH (120) / D γ-Al2O3 (440), wherein D(120) represents the grain size of the crystal face corresponding to the AlOOH (120) peak in the XRD spectrum; the 120 peak refers to the characteristic peak with 2θ of 25.5-29.9° in the XRD spectrum; D(440) represents the grain size of the crystal face corresponding to the γ-Al2O3 (440) peak in the XRD spectrum; and the 440 peak refers to the characteristic peak with 2θ of 63.6-69.1° in the XRD spectrum.

[0008] In the alumina carrier of the present application, the coverage of the flaky AlOOH on the outer surface of the alumina carrier is 85%-100%, wherein the coverage refers to the percentage of the surface occupied by the flaky AlOOH crystal grains on the outer surface of the alumina carrier.

[0009] The second aspect of the present application provides a method for preparing an alumina carrier, comprising the following steps: sealingly heat-treating granular gamma phase alumina in an aqueous propylene oxide solution, separating the treated material by solid-liquid separation, and drying the solid phase material to obtain the alumina carrier.

[0010] In the method, the granular gamma phase alumina has a particle size of 2-8.0 mm, preferably a specific surface area of 150-300 m 2 / g, a pore volume of 0.6-1.1 mL / g, a pore diameter of less than 10 nm, a pore volume of pores with a pore diameter of less than 10 nm accounting for less than 40% of the total pore volume, and a pore volume of pores with a pore diameter of 10-30 nm accounting for 40%-60% of the total pore volume. The shape can be a conventional shape of an alumina carrier, such as a spherical shape, a cylindrical strip shape, a trilobal shape, a quadrilobal shape, etc. The particle size is generally 2-8.0 mm, the diameter is about 0.2-3.0 mm, and the length is about 3-8.0 mm.

[0011] In the method, the granular gamma phase alumina can be a commercially available product or prepared according to an existing method. For example, the granular gamma phase alumina can be prepared by the following method: uniformly mixing pseudo-boehmite, a extrusion aid, and a physical pore-expanding agent, adding a peptizing agent to knead, drying, and calcining to obtain the granular gamma phase alumina. The pseudo-boehmite can be prepared by any method, and is preferably pseudo-boehmite with a pore volume of pores with a pore diameter of 10-30 nm accounting for more than 45% of the total pore volume. The extrusion aid is sesbania powder, and the addition amount is 0.1wt%-0.5wt% of the weight of the granular gamma phase alumina. The physical pore-expanding agent is starch, activated carbon, crop straw particles, etc., and the addition amount is 1wt%-5wt% of the weight of the granular gamma phase alumina. The peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and oxalic acid, and the addition amount is 0.5wt%-1.5wt% of the weight of the granular gamma phase alumina. The drying temperature is 100-160℃, and the drying time is 6-10 hours. The calcining temperature is 450-700℃, and the calcining time is 4-6 hours. The calcining is performed in an oxygen-containing atmosphere, preferably an air atmosphere.

[0012] In the method, the aqueous propylene oxide solution has a mass percentage concentration of 2.5%-12%, preferably 4%-8%. The mass ratio of the aqueous propylene oxide solution to the alumina carrier is 3:1-10:1, preferably 4:1-8:1.

[0013] In the method, the sealing heat treatment is performed in a closed container, which is preferably an autoclave. The sealing heat treatment is two-step sealing heat treatment, i.e., first sealing heat treatment at 60-100℃ for 1-4 hours, and then sealing heat treatment at 110-180℃, preferably 120-160℃, for 14-20 hours, preferably 16-20 hours.

[0014] The drying temperature in the method is 100-160℃, and the drying time is 2-8 hours.

[0015] The third aspect of the present application provides a hydrogenation catalyst and a preparation method thereof.

[0016] The hydrogenation catalyst comprises a carrier and an active metal component, wherein the carrier is the alumina carrier described above. The active metal component is a group VIB and group VIII metal, wherein the mass ratio K of the active metal component content at the surface sheet particle microzone to the active metal component content at the center spherical particle microzone in terms of oxide is 1.1-1.5, and further preferably the mass ratio K1 of the group VIB metal oxide content at the surface sheet alumina grain microzone to the group VIB metal oxide at the center spherical alumina grain microzone in terms of oxide is 1.1-1.50, and the mass ratio K2 of the group VIII metal at the surface sheet alumina grain to the group VIII metal at the center spherical alumina grain microzone in terms of oxide is 1.1-1.5.

[0017] The preparation method of the hydrogenation catalyst comprises the following steps: impregnating the alumina carrier described above with an impregnation solution containing an active component, and drying and calcining the impregnated material to obtain the hydrogenation catalyst. Preferably, different concentrations of active component impregnation solution are used to continuously impregnate the alumina carrier, i.e. first impregnate the alumina carrier with a low-concentration active component impregnation solution I, and then impregnate the alumina carrier with a high-concentration active component impregnation solution II, and the impregnated alumina carrier is dried and calcined to obtain the final hydrogenation catalyst.

[0018] The impregnation solution I and the impregnation solution II containing the active component are solutions containing a group VIB and group VIII metal, the group VIB metal is selected from one or more of W and Mo, and the group VIII metal is selected from one or more of Co and Ni. The content of the group VIB metal in the impregnation solution I is 8.5%-11.5g / 100mL in terms of metal oxide, and the content of the group VIII metal is 1.5%-3.0g / 100mL in terms of metal oxide. The amount of the impregnation solution I used is 75%-95% of the saturated water absorption capacity of the alumina carrier. The content of the group VIB metal in the impregnation solution II is 11.5%-15.5g / 100mL in terms of metal oxide, and the content of the group VIII metal is 3.0-5.0g / 100mL in terms of metal oxide. The amount of the impregnation solution II used is the remaining amount of the saturated water absorption capacity of the alumina carrier. The active components in the impregnation solution I and the impregnation solution II can be the same or different. Preferably, the impregnation solution I and the impregnation solution II are solutions containing Mo and Ni.

[0019] The drying temperature is 100-160℃, the drying time is 2-8 hours, the calcination temperature is 450-550℃, and the calcination time is 4-6 hours.

[0020] Compared with the prior art, the present application has the following advantages:

[0021] (1) The present application firstly seals and heat-treats the alumina carrier precursor in a solution containing propane. During the low-temperature sealed heat-treatment, propylene oxide is hydrolyzed to form an alcohol solution and the solution is weakly alkaline. During the high-temperature sealed hydrothermal treatment, the surface grains of the alumina carrier grow outward in situ under the alkaline and alcohol solution environment and form flaky AlOOH grains. The coverage of the AlOOH grains on the outer surface of the alumina carrier is high, the ratio of the grain size of the crystal plane corresponding to the AlOOH (120) peak to the grain size of the crystal plane corresponding to the γ-Al2O3 (211) peak is large, and the adjustment effect on the outer surface pores of the carrier, especially the large pores, is obvious. After calcination, the AlOOH phase changes into alumina, which forms open pores of 40-300 nm on the surface of the carrier. Meanwhile, the flaky AlOOH grain structure is uniform, and the combination with the surface of the carrier is strong, so that the pores formed are firm.

[0022] (2) The surface layer of the alumina carrier in the present application is flaky AlOOH grains. During the impregnation of the active metal component and the calcination, the AlOOH grains change into γ-Al2O3, and the phase change process of the AlOOH grains cooperates with the active metal component, so that the active metal component and the alumina carrier are appropriately combined, the formation of nickel-aluminum spinel phase is reduced, and the catalytic activity of the catalyst is improved. In addition, the outer surface pores of the hydrodemetallization catalyst in the present application are formed by the accumulation of flaky grains, the flaky grains on the surface are easy to contact with the molecules of the residual oil reactants during the reaction, and the pore structure on the surface of the catalyst is open, which is beneficial to the diffusion of the large molecules of the reactants to the inside of the catalyst.

[0023] (3) When preparing the hydrogenation catalyst, the alumina carrier is impregnated with active metals of different concentrations, so that the open pores formed by the flaky grain structure on the surface of the catalyst have a higher content of active metals. The active metal component and the pores of the catalyst are effectively matched, so that the final catalyst has high activity and high activity stability when applied to the heavy oil hydrodemetallization reaction. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 XRD spectra of the alumina carrier precursor and the alumina carrier of Example 1.

[0025] Figure 2 Low-magnification SEM image of the surface of the alumina carrier prepared in Example 1.

[0026] Figure 3 High-magnification SEM image of the surface of the alumina carrier prepared in Example 1.

[0027] Figure 4 Low-magnification SEM image of the surface of the alumina carrier prepared in Comparative Example 2.

[0028] Figure 5 High magnification SEM image of the surface of the alumina support prepared for Comparative Example 2. DETAILED DESCRIPTION

[0029] The technical solutions and technical effects of the present application are further illustrated below in connection with examples, but are not limited to the following examples. In the present application, wt% represents mass fraction.

[0030] BET method: N2 physical adsorption-desorption was applied to characterize the pore structure of the support of the examples and comparative examples, and the specific operation was as follows: an ASAP-2420 type N2 physical adsorption-desorption instrument was used to characterize the pore structure of the sample. A small amount of sample was vacuum treated at 300°C for 3-4 hours, and finally the product was placed in liquid nitrogen at low temperature (-200°C) for nitrogen adsorption-desorption test. The specific surface area was obtained according to the BET equation, and the distribution rate of the pore volume and the pore diameter below 30 nm was obtained according to the BJH model.

[0031] Scanning electron microscopy was applied to characterize the microstructure of the alumina support, and the specific operation was as follows: JSM-7500F scanning electron microscopy was used to characterize the microstructure of the support, with an acceleration voltage of 5KV, an acceleration current of 20μA, and a working distance of 8mm.

[0032] Scanning electron microscopy-energy dispersive spectrometry was applied to characterize the micro-area composition of the sample, and the specific operation was as follows: JSM-7500F scanning electron microscopy equipped with EDAX energy dispersive spectrometry was used, with an acceleration voltage of 30kV, a probe current of 11μA, and a working distance of 8mm. In the test, 20 surface sheet particle accumulation micro-areas and central granular particle accumulation micro-areas were selected as measurement areas, the content of group VIB and group VIII metal oxides in the corresponding areas was measured, and the average value was calculated to obtain K1 value and K2 value.

[0033] Preparation of alumina support precursor:

[0034] 500 grams of pseudo-boehmite (prepared by aluminum sulfate-sodium metaaluminate method) were weighed, 2.5 grams of sesbania powder and 7 grams of carbon black were added and mixed uniformly, then an appropriate amount of 0.5% acetic acid solution was added to the mixture and kneaded uniformly, and then extruded into strips. The formed material was dried at 120°C for 8 hours and calcined at 500°C for 5 hours to obtain an alumina support precursor S0. The properties of the alumina support precursor are shown in Table 1, and the XRD spectrum is shown in Figure 1 A.

[0035] Example 1

[0036] (1) Weigh 100 g of alumina support precursor SO and add 550 g of 6.2% propylene oxide aqueous solution. Transfer the mixture to an autoclave, seal it, and place the autoclave in an oven at 70°C for 2.8 hours. Then, raise the temperature to 135°C and seal for 18 hours. After treatment, cool, wash, and filter the material. Dry the solid material at 120°C for 6 hours to obtain the alumina support. The XRD pattern of the support is shown in [Figure number missing]. Figure 1 B, the properties of the carrier are shown in Table 1, and the scanning electron microscope image of the outer surface of the carrier is shown in [Table 1]. Figure 2 , Figure 3 .

[0037] (2) Weigh 50 g of alumina support S1 and impregnate the alumina support with 40 mL of impregnation solution I with a molybdenum oxide concentration of 9.0 g / 100 mL and a nickel oxide concentration of 2.2 g / 100 mL. Then, continue to spray and impregnate the alumina support with impregnation solution II with a molybdenum oxide concentration of 12.0 g / 100 mL and a nickel oxide concentration of 3.2 g / 100 mL until the support is saturated with adsorption. The impregnated material is dried at 120 °C for 6 hours and calcined at 450 °C for 5 hours to obtain the hydrogenation demetallization catalyst Cat-1 of the present invention. The properties of the catalyst are shown in Table 2.

[0038] Example 2

[0039] Same as Example 1, except that in step (1), the concentration of propylene oxide is 5.5%, the solution volume is 630 g, and the hydrothermal treatment is first performed at 80°C for 2.5 hours, and then at 145°C for 17.5 hours to obtain the alumina support S2 of the present invention. The properties of the support are shown in Table 1. In step (2), the concentration of molybdenum oxide in impregnation solution I is 8.5 g / 100 mL, the concentration of nickel oxide is 2.1 g / 100 mL, and the solution volume is 42 mL. The concentration of molybdenum oxide in impregnation solution II is 12.5 g / 100 mL, and the concentration of nickel oxide is 3.3 g / 100 mL to obtain the hydrogenation demetallization catalyst Cat-2 of the present invention. The properties of the catalyst are shown in Table 2.

[0040] Example 3

[0041] Same as Example 1, except that in step (1), the concentration of propylene oxide is 4.5%, the solution volume is 720 g, and the hydrothermal treatment is first performed at 60°C for 3.5 hours, and then at 160°C for 16 hours to obtain the alumina support S3 of the present invention. The properties of the support are shown in Table 1. In step (2), the concentration of molybdenum oxide in impregnation solution I is 8.5 g / 100 mL, the concentration of nickel oxide is 2.3 g / 100 mL, and the solution volume is 45 mL. The concentration of molybdenum oxide in impregnation solution II is 13.0 g / 100 mL, and the concentration of nickel oxide is 3.4 g / 100 mL to obtain the hydrogenation demetallization catalyst Cat-3. The properties of the catalyst are shown in Table 2.

[0042] Example 4

[0043] The same as Example 1 except that the concentration of propylene oxide in step (1) is 7.6%, the solution used is 430 g, and the hydrothermal treatment is first at 90°C for 1.5 hours and then at 120°C for 19 hours to produce an alumina support S4 according to the application. The properties of the support are given in Table 1. In step (2), the concentration of molybdenum oxide in impregnation solution I is 9.2 g / 100 mL and the concentration of nickel oxide is 2.3 g / 100 mL, and the concentration of molybdenum oxide in impregnation solution II is 12.5 g / 100 mL and the concentration of nickel oxide is 3.3 g / 100 mL to produce a hydrodemetallization catalyst Cat-4. The properties of the catalyst are given in Table 2.

[0044] Comparative Example 1

[0045] The same as Example 1 except that the aqueous propylene oxide solution is replaced by an aqueous ammonia solution of the same mass concentration to produce a comparative alumina support S5 and a comparative hydrodemetallization catalyst Cat-5. The properties of the alumina support are given in Table 1 and the properties of the hydrodemetallization catalyst are given in Table 2.

[0046] Comparative Example 2

[0047] The same as Example 1 except that the aqueous propylene oxide solution is replaced by an aqueous ethylene oxide solution of the same concentration to produce a comparative alumina support S6 and a comparative hydrodemetallization catalyst Cat-6. The properties of the alumina support are given in Table 1 and the properties of the hydrodemetallization catalyst are given in Table 2. Figure 5

[0048] Comparative Example 3

[0049] The same as Example 1 except that the concentration of propylene oxide is 1% to produce a comparative alumina support S7 and a comparative hydrodemetallization catalyst Cat-7. The properties of the alumina support are given in Table 1 and the properties of the hydrodemetallization catalyst are given in Table 2.

[0050] Comparative Example 4

[0051] The same as Example 1 except that the hydrothermal treatment is a one-step hydrothermal treatment at 60°C for 20 hours to produce a comparative alumina support S8 and a comparative hydrodemetallization catalyst Cat-8. The properties of the alumina support are given in Table 1 and the properties of the hydrodemetallization catalyst are given in Table 2.

[0052] Table 1 Properties of the alumina supports

[0053]

[0054] From the data in Table 1 and Figure 2 、 3 , Figure 4 、 5 ​It can be seen that the alumina carrier prepared by the method of the present application has higher 10-30 nm pore content, and the surface sheet particles of the alumina carrier are accumulated to form 40-300 nm pores, and the surface pores are open.

[0055] Table 2 Hydrodemetallization catalyst properties

[0056]

[0057] Example 5

[0058] The hydrodemetallization catalysts Cat-1, Cat-2, Cat-3, Cat-4 prepared by the method of the present application and the hydrodemetallization catalysts Cat-5, Cat-6, Cat-7, Cat-8 prepared by the method of the comparative examples were respectively loaded into a fixed bed hydrogenation reactor, and the raw materials (see Table 2) were treated, and the test conditions were as follows: reaction temperature 380℃, hydrogen / oil volume ratio 780, liquid hourly space velocity 1.0h-1, hydrogen partial pressure 15.0MPa, continuous operation 2000 hours, and the impurity removal properties are shown in Table 5. -1

[0059] Table 4 Raw oil properties

[0060] Item Density (20°C), g / cm 3 ]] 0.95 S, wt% 2.2 N, wt% 0.26 Ni, pg / g 31.5 V, pg / g 79.6

[0061] Table 5 Catalyst evaluation results

[0062]

[0063] It can be seen from the results in Table 5 that the hydrodemetallization catalyst prepared by the method of the present application has higher Ni and V removal activity and activity stability compared with the comparative hydrodemetallization catalyst.​

Claims

1. An alumina support, characterized by: The alumina carrier is a mixed phase of γ-Al2O3 and AlOOH, wherein AlOOH is in-situ oriented growth on the outer surface of the alumina carrier, the grain morphology of AlOOH is a sheet structure; the grain size of AlOOH is 100-600 nm; the ratio H of the grain size of the crystal face corresponding to the AlOOH (120) peak to the grain size of the crystal face corresponding to the γ-Al2O3 (440) peak is 3.5-5.0, H=D AlOOH (120) / D γ-Al2O3 (440), wherein D(120) represents the grain size of the crystal face corresponding to the AlOOH (120) peak in the XRD spectrum; the 120 peak refers to the characteristic peak with 2θ of 25.5-29.9° in the XRD spectrum; D(440) represents the grain size of the crystal face corresponding to the γ-Al2O3 (440) peak in the XRD spectrum; the 440 peak refers to the characteristic peak with 2θ of 63.6-69.1° in the XRD spectrum; The application relates to a preparation method of an alumina carrier, which comprises the following steps: sealingly heat-treating granular gamma-phase alumina in a propylene oxide aqueous solution, performing solid-liquid separation on the treated material, and drying the solid-phase material to obtain the alumina carrier; the particle size of the granular gamma-phase alumina is 2-8.0 mm, the specific surface area of the gamma-phase alumina is 150-300 m<2> / g, the pore volume is 0.6-1.1 mL / g, the pore diameter of pores with a pore volume accounting for less than 40% of the total pore volume is less than 10 nm, and the pore diameter of pores with a pore volume accounting for 40%-60% of the total pore volume is 10-30 nm; the preparation method of the granular gamma-phase alumina comprises the following steps: uniformly mixing pseudo-boehmite, a extrusion aid, and a physical pore-expanding agent, adding a peptizing agent to knead, drying, and calcining to obtain the granular gamma-phase alumina; the extrusion aid is pearl millet powder, and the addition amount is 0.1wt%-0.5wt% of the weight of the granular gamma-phase alumina; the physical pore-expanding agent is starch, activated carbon, or crop straw particles, and the addition amount is 1wt%-5wt% of the weight of the granular gamma-phase alumina; the peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and oxalic acid, and the addition amount of the peptizing agent is 0.5wt%-1.5wt% of the weight of the granular gamma-phase alumina; the drying temperature is 100-160 DEG C, and the drying time is 6-10 hours; the calcining temperature is 450-700 DEG C, the calcining time is 4-6 hours, and the calcining is performed in an oxygen-containing atmosphere. 2 / g, pore volume 0.6-1.1 mL / g, pore diameter less than 10 nm, pore volume of pores with a pore diameter less than 10 nm accounts for less than 40% of total pore volume, pore diameter of 10-30 nm, pore volume of pores with a pore diameter of 10-30 nm accounts for 40-60% of total pore volume; granular gamma-phase alumina is prepared by mixing pseudo-boehmite, extrusion aid, and physical pore-expanding agent, adding peptizing agent, kneading, drying, and calcining; extrusion aid is pearl millet powder, addition amount is 0.1-0.5 wt% of weight of granular gamma-phase alumina; physical pore-expanding agent is starch, activated carbon, or crop straw particles, addition amount is 1-5 wt% of weight of granular gamma-phase alumina; peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and oxalic acid, addition amount of peptizing agent is 0.5-1.5 wt% of weight of granular gamma-phase alumina; drying temperature is 100-160 DEG C, drying time is 6-10 hours; calcining temperature is 450-700 DEG C, calcining time is 4-6 hours, calcining is performed in oxygen-containing atmosphere. The mass percentage concentration of the propylene oxide aqueous solution is 2.5%-12%, and the mass ratio of the propylene oxide aqueous solution to the alumina carrier is 3:1-10:

1. The sealing heat treatment is carried out in a closed container, and is two-step sealing heat treatment, that is, first sealing heat treatment at 60-100℃ for 1-4 hours, and then treatment at 110-180℃ for 14-20 hours.

2. The alumina support of claim 1, wherein: The coverage of AlOOH on the outer surface of the alumina carrier is 85%-100%, wherein the coverage refers to the percentage of the surface occupied by the flaky AlOOH crystal grains of the alumina carrier to the outer surface of the alumina carrier.

3. A process for the preparation of the alumina support according to claim 1 or 2, characterized in that: The method comprises the following steps: immersing the particulate γ-phase alumina into the propylene oxide aqueous solution for sealing heat treatment, and then performing solid-liquid separation on the treated material, and drying the solid-phase material to obtain the alumina carrier.

4. The method of claim 3, wherein: The particle size of the granular gamma phase alumina is 2-8.0mm, the specific surface area of the gamma phase alumina is 150-300m 2 / g, the pore volume is 0.6-1.1mL / g, the pore volume of the pores with pore diameter less than 10nm accounts for 40% or less of the total pore volume, and the pore volume of the pores with pore diameter of 10-30nm accounts for 40%-60% of the total pore volume.

5. The method of claim 3, wherein: The method for preparing the particulate γ-phase alumina comprises the following steps: uniformly mixing pseudo-boehmite, extrusion aid, and physical pore-expanding agent, adding a peptizing agent to knead and form, drying, and calcining to obtain the particulate γ-phase alumina; the pseudo-boehmite is prepared by any method, and the pseudo-boehmite with a pore volume of 10-30 nm pores accounting for more than 45% of the total pore volume; the extrusion aid is sesbania powder, and the addition amount is 0.1wt%-0.5wt% of the weight of the particulate γ-phase alumina; the physical pore-expanding agent is starch, activated carbon, or crop straw particles, and the addition amount is 1wt%-5wt% of the weight of the particulate γ-phase alumina; the peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and oxalic acid, and the addition amount of the peptizing agent is 0.5wt%-1.5wt% of the weight of the particulate γ-phase alumina; the drying temperature is 100-160℃, and the drying time is 6-10 hours; the calcination temperature is 450-700℃, and the calcination time is 4-6 hours, and the calcination is carried out in an oxygen-containing atmosphere.

6. The method of claim 3, wherein: The mass percentage concentration of the propylene oxide aqueous solution is 2.5%-12%, and the mass ratio of the propylene oxide aqueous solution to the alumina carrier is 3:1-10:

1.

7. The method of claim 3, wherein: The sealing heat treatment is carried out in a closed container, and is two-step sealing heat treatment, that is, first sealing heat treatment at 60-100℃ for 1-4 hours, and then treatment at 110-180℃ for 14-20 hours.

8. The method of claim 3, wherein: The drying temperature is 100-160℃, and the drying time is 2-8 hours.

9. The use of the alumina carrier according to claim 1 or 2 in a heterogeneous catalytic reaction.

10. A hydrogenation catalyst characterized by: The catalyst comprises the alumina carrier according to claim 1 or 2 and a hydrogenation active metal component.

11. The hydrogenation catalyst of claim 10, wherein: The hydrogenation active metal component is a group VIB and group VIII metal, and the mass ratio K of the content of the hydrogenation active metal component at the surface flaky particle microzone to the content of the hydrogenation active metal component at the central spherical particle microzone in terms of oxides is 1.1-1.

5.

12. A process for preparing the hydrogenation catalyst of claim 10, characterized by The method comprises the following steps: immersing the particulate γ-phase alumina into the propylene oxide aqueous solution for sealing heat treatment, and then performing solid-liquid separation on the treated material, and drying the solid-phase material to obtain the alumina carrier.

13. The method of claim 12, wherein: The alumina carrier is continuously impregnated with impregnation solutions of different concentrations of hydrogen active metal components, i.e. the alumina carrier is first impregnated with a low-concentration hydrogen active metal component impregnation solution I, and then impregnated with a high-concentration hydrogen active metal component impregnation solution II, and the impregnated alumina carrier is dried and calcined to obtain a hydrogenation catalyst.

14. The method of claim 13, wherein: The impregnation solution I and the impregnation solution II of the hydrogen active metal component are solutions containing Group VIB and Group VIII metals, the Group VIB metal is selected from one or more of W and Mo, and the Group VIII metal is selected from one or more of Co and Ni; the content of the Group VIB metal in the impregnation solution I is 8.5%-11.5g / 100mL in terms of metal oxide, the content of the Group VIII metal is 1.5%-3.0g / 100mL in terms of metal oxide, and the amount of the impregnation solution I is 75%-95% of the saturated water absorption amount of the alumina carrier; the content of the Group VIB metal in the impregnation solution II is 11.5%-15.5g / 100mL in terms of metal oxide, the content of the Group VIII metal is 3.0-5.0g / 100mL in terms of metal oxide, and the amount of the impregnation solution II is the balance of the saturated water absorption amount of the alumina carrier.

15. The method of claim 12, wherein: The drying temperature is 100-160℃, and the drying time is 2-8 hours; the calcination temperature is 450-550℃, and the calcination time is 4-6 hours.

Images