A process for the preparation of a hydrodemetallation catalyst

Abstract

The application discloses a preparation method of a hydrodemetallization catalyst, and comprises the following steps: roasting aluminum nitrate, then impregnating and treating the aluminum nitrate with an impregnation solution containing W and Co, drying and roasting to obtain a modified aluminum oxide compound; (2) sealing and hydrothermally treating the modified aluminum oxide compound in a propylene oxide solution to obtain modified sheet-like pseudo-boehmite HP; (3) mixing the pseudo-boehmite P2 with the HP to obtain a mixture H1, and then rolling the H1 to form a spherical precursor S1; (4) mixing the pseudo-boehmite P2 with the HP to obtain a mixture H2, then mixing the spherical precursor S1 with the H2 and continuing to roll to form a spherical precursor S2; (5) mixing the HP with the S2, rolling, drying, roasting, loading Mo and Ni, and thus obtaining the hydrodemetallization catalyst. The method is particularly suitable for the hydroprocessing of heavy residual oil with high content of impurities such as gum and asphaltene.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of catalyst preparation, and particularly relates to a preparation method of a hydrodemetallization catalyst. BACKGROUND

[0002] With the heavy and poor quality of crude oil and the increasing demand for high-quality light fuel oil, the processing technology of poor heavy oil has become the focus of research of major oil companies and petroleum research institutions. Among them, the hydroprocessing technology is one of the most effective technical solutions to improve the quality of poor heavy oil and provide high-quality raw oil for downstream devices, and is currently widely concerned. Heavy oil molecules have a complex three-dimensional structure. In the process of catalytic hydrogenation, heavy oil macromolecules are adsorbed and deposited on the surface or pore of the catalyst, increasing the internal diffusion resistance of the reaction and causing the apparent activity of the catalyst to decrease. At the same time, heavy oil contains a large amount of coke precursors, which will generate coke under certain conditions and deposit in the pores, causing the active center of the catalyst to be poisoned. Therefore, the catalyst with large pore volume and large pore diameter has strong metal and carbon capacity, which can slow down the deactivation of the catalyst and prolong the operation cycle of the catalyst.

[0003] CN201510191156.7 discloses a heavy oil hydrogenation catalyst and a preparation method thereof. The catalyst comprises an alumina carrier composed of flaky polycrystalline γ-alumina and a hydrogenation active metal. The preparation method of the catalyst is as follows: flaky γ-polycrystalline alumina raw powder is added to a binder and a extrusion aid, kneaded, formed, dried and calcined to obtain an alumina carrier, and an active metal is loaded on the obtained alumina carrier by a conventional method. The preparation method of the flaky γ-polycrystalline alumina comprises the following steps: (1) mixing inorganic aluminum salt, low-carbon alcohol and / or water, and low-carbon alkylene oxide uniformly to form a gel, and then aging the gel; (2) soaking the gel obtained in step (1) with low-carbon alcohol, and then drying and calcining; (3) immersing the material obtained in step (2) in ammonia water for closed hydrothermal treatment, solid-liquid separation, and drying to obtain flaky γ-polycrystalline alumina raw powder. The invention adjusts the pore structure of the carrier by adding flaky polycrystalline γ-alumina to the alumina carrier, but the preparation process of the flaky polycrystalline γ-alumina is relatively complex, and on the other hand, the matching degree of the active metal component and the catalyst pores needs to be further improved.

[0004] CN104646008A discloses a poor heavy oil hydrodesulfurization and demetallization catalyst and a preparation method thereof. The catalyst uses alumina as a carrier, and VIB and VIII elements, especially Ni-Mo, as active components. The pore volume of the catalyst is 0.61-0.70 mL / g, the specific surface area is 155-200 m 2 / g, and the average pore diameter is 13.0-18.0 nm, and the catalyst is prepared by treating the carrier particles after molding and calcination with acid solutions with continuously increasing concentrations, although this method can make the average pore diameter of the final catalyst gradually increase from the center to the outer surface of the catalyst particle diameter to some extent, but this treatment mode is difficult to form larger pores on the surface of the carrier. SUMMARY

[0005] In view of the deficiencies in the prior art, the present application provides a preparation method of a hydrodemetallization catalyst. The hydrodemetallization catalyst prepared by the method has wide surface pores, and the high-activity hydrodemetallization active sites have high matching degree with the pores of the catalyst. The hydrodemetallization catalyst is particularly suitable for use in the hydroprocessing process of heavy residual oil with high content of impurities such as resin and asphaltene.

[0006] The preparation method of the hydrodemetallization catalyst of the present application comprises the following contents:

[0007] (1) calcining aluminum nitrate, impregnating and treating the calcined material with an impregnating solution containing W and Co, drying,

[0008] obtaining a modified aluminum oxide compound by calcination;

[0009] (2) crushing and sieving the modified aluminum oxide compound, sealing and hydrothermally treating the sieved material in a propylene oxide solution, and obtaining modified sheet-like pseudo-boehmite HP by drying the treated material;

[0010] (3) mixing pseudo-boehmite P2 and the modified sheet-like pseudo-boehmite HP to obtain a mixture H1,

[0011] obtaining a spherical precursor S1 by ball-rolling the mixture H1;

[0012] (4) mixing pseudo-boehmite P2 and the modified sheet-like pseudo-boehmite HP to obtain a mixture H2,

[0013] and mixing the spherical precursor S1 and the mixture H2 to continue ball-rolling to obtain a spherical precursor S2;

[0014] (5) mixing the modified sheet-like pseudo-boehmite HP and the spherical precursor S2, ball-rolling, and then drying and calcining to obtain a modified alumina carrier;

[0015] (6) impregnating the modified alumina carrier with an impregnating solution containing Mo and Ni, and obtaining a hydrodemetallization catalyst by drying and calcining the impregnated material.

[0016] In the method of the present application, the aluminum nitrate in step (1) is calcined at a temperature of 450-650°C for 4-8 hours.

[0017] In the method, the impregnating solution containing W and Co in step (1) has a W concentration of 1 g / 100 mL to 3.5 g / 100 mL (calculated as WO3) and a Co concentration of 0.3 g / 100 mL to 1.0 g / 100 mL (calculated as CoO), the impregnation is performed by over-volume impregnation, the impregnation time is 0.5 to 2 hours, the drying condition of the impregnated material is 80 to 140 ℃ for 4 to 8 hours, and the calcination condition is 400 to 550 ℃ for 4 to 8 hours.

[0018] In the method, the material is crushed to a particle size of more than 100 mesh in step (2).

[0019] In the method, the propylene oxide solution concentration in step (2) is 2.5 wt% to 12 wt%, preferably 4 wt% to 8 wt%, and the mass ratio of the propylene oxide solution to the modified aluminum oxide compound is 3:1 to 10:1, preferably 4:1 to 8:1.

[0020] In the method, the sealing hydrothermal treatment in step (2) is performed in a sealed container, preferably an autoclave, the hydrothermal treatment temperature is 110 to 180 ℃, preferably 120 to 160 ℃, the treatment time is 4 to 8 hours, and the pressure in the sealed container during the hydrothermal treatment is autogenous pressure.

[0021] In the method, the drying temperature in step (2) is generally 80 to 160 ℃, and the drying time is 4 to 8 hours.

[0022] In the method, the pseudo-boehmite P2 particle morphology in step (3) is generally granular, which can be a commercially available product or a pseudo-boehmite prepared by methods such as acid precipitation, alkali precipitation, and alcohol aluminum hydrolysis, and is preferably a pseudo-boehmite with a pore size of greater than 10 nm.

[0023] In the method, the mass ratio of the modified sheet-like pseudo-boehmite HP to the pseudo-boehmite P2 in the H1 mixture in step (3) is 1:9 to 1:3.

[0024] In the method, the rolling ball forming in step (3) is performed on a rotating disc forming machine, the rotating disc forming machine has a rotating operation condition of a disc inclination angle of 40 to 70° and a disc rotation speed of 10 to 30 rpm, the material forming time in the disc is 10 to 120 minutes, the radius of the spherical precursor S1 is 0.2r to 0.5r (where r is the radius of the final modified alumina carrier, i.e., the straight-line distance from the center of the sphere to the outer surface), and a water solution containing a gel solvent is sprayed into the material during the rolling ball forming; the water solution containing the gel solvent is one or a mixture of several of nitric acid, phosphoric acid, oxalic acid, and acetic acid, and the mass concentration of the solution is 1% to 3%, preferably an acetic acid water solution.

[0025] In the method, the mass ratio of the modified sheet-like pseudo-boehmite HP to the pseudo-boehmite P2 in step (4) is 3:7-1:1.

[0026] In the method, the rolling ball forming in step (4) is performed in a rotary table forming machine, and the rotary table forming machine has an operation condition that the inclination angle of the rotary table is 40-70º and the rotary speed of the rotary table is 10-30 rpm; the forming time of the material in the rotary table is 10-120 min. The radius of the spherical precursor S2 is 0.5r-0.9r, wherein r is the radius of the final modified alumina carrier, i.e. the straight-line distance from the center of the sphere to the outer surface. A water solution containing a gelatinizing solvent is sprayed into the material during the rolling ball forming; the water solution containing the gelatinizing solvent is one or a mixture of several of the water solutions of nitric acid, phosphoric acid, oxalic acid and acetic acid, and the mass concentration of the solution is 1%-3%, and the water solution of acetic acid is preferred.

[0027] In the method, the rolling ball forming in step (5) is performed in a rotary table forming machine, and the rotary table forming machine has an operation condition that the inclination angle of the rotary table is 40-70º and the rotary speed of the rotary table is 10-30 rpm; the forming time of the material in the rotary table is 10-60 min, and the diameter of the final sphere is 5-10 mm. A water solution containing a gelatinizing solvent is sprayed into the material during the rolling ball forming; the water solution containing the gelatinizing solvent is one or a mixture of several of the water solutions of nitric acid, phosphoric acid, oxalic acid and acetic acid, and the mass concentration of the solution is 1%-3%, and the water solution of acetic acid is preferred.

[0028] In the method, the drying time in step (5) is 1-8 hours, preferably 2-6 hours, and the drying temperature is 60℃-180℃, preferably 80℃-150℃; the calcination temperature is 350-800℃, preferably 500-750℃, the calcination time is 2-6 hours, preferably 2-4 hours.

[0029] In the method, the concentration of Mo in the Mo and Ni containing impregnation solution in step (6) is 5.5g / 100mL-12.5g / 100mL as MoO3, and the concentration of Ni is 1.4g / 100mL-3.2g / 100mL as NiO; equal volume impregnation is adopted during impregnation, and the drying condition of the material after impregnation is 80-120℃ for 4-8 hours, and the calcination condition is 400-550℃ for 4-8 hours.

[0030] Compared with the prior art, the method has the following advantages:

[0031] (1) The present application firstly roasts aluminum nitrate, and then pre-impregnates the roasted material with active metals to obtain W and Co modified aluminum oxide compounds. When the W and Co modified aluminum oxide compounds are hydrothermally treated in propylene oxide solution, the aluminum oxide compounds grow directionally into W and Co modified sheet-like pseudoboehmite. The active metal components grow again with the aluminum-containing compounds during the hydrothermal treatment. This treatment process can improve the interaction between the active metals and the sheet-like pseudoboehmite. The sheet-like pseudoboehmite crystal grains interweave and accumulate to form a large number of 50-150 nm macroporous channels. The active metal components have a relatively high content in the macropores, and have strong macropore volume metal and anti-accumulation carbon capacity. The hydrogenation active sites are well matched with the macropores, which ensures high activity of the catalyst and high activity stability of the catalyst. At the same time, the sheet-like crystal grains support each other, which can prevent the accumulation channels from being damaged during the shaping of the carrier. When the sheet-like pseudoboehmite is used as a raw material to prepare an alumina carrier, the macropore content of the carrier can be effectively improved.

[0032] (2) The present application selects raw materials with different morphologies and structures to prepare the carrier by step-by-step rolling. The content of the active metal modified sheet-like pseudoboehmite material is adjusted to adjust the pore channel distribution of the carrier. The prepared carrier has a gradient distribution of macropore content and pore size distribution, i.e., the surface layer has a high macropore content, a large pore size, and an open channel, the middle layer has a lower macropore content, a smaller pore size, and a narrower channel, and the core layer has a lower macropore content, a smaller pore size, and a narrower channel. This pore channel structure is beneficial to the diffusion of heavy oil reactant molecules to the inside of the catalyst, and can effectively reduce the deposition of metals and carbon on the surface of the catalyst, and is particularly suitable for heavy oil hydroprocessing processes with high content of metals (Ni, V), gum, and asphaltene. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 SEM image of the active metal modified sheet-like pseudoboehmite HP1 prepared in Example 1.

[0034] Figure 2 SEM image of the material HP5 prepared in Comparative Example 3.

[0035] Figure 3 SEM image of the material HP7 prepared in Comparative Example 4. IMPLEMENTATION

[0036] The technical solutions and technical effects of the present application will be further illustrated by the following examples, but are not limited to the following examples. In the present application, wt% represents mass fraction.

[0037] BET method: The pore structure of the support of the examples and the comparative examples was characterized by N2 physical adsorption-desorption, 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.

[0038] The microstructure of the alumina support was characterized by scanning electron microscopy, and the specific operation was as follows: a JSM-7500F scanning electron microscope 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.

[0039] Mercury intrusion method: The pore diameter distribution of the support of the examples and the comparative examples was characterized by a mercury intrusion instrument, and the specific operation was as follows: an American Mac AutoPore9500 type full-automatic mercury intrusion instrument was used to characterize the pore distribution of the sample. After the sample was dried and weighed, it was loaded into the dilatometer, and was degassed for 30 minutes under the vacuum condition given by the instrument, and was loaded with mercury. Then the dilatometer was placed in the autoclave, and was exhausted. Then the pressure was increased and the pressure was decreased. The mercury contact angle was 130º, and the mercury interfacial tension was 0.485N.cm -1 , and the distribution rate of the pore diameter above 100nm was measured by the mercury intrusion method.

[0040] Most probable pore diameter determination: the pore diameter differential distribution curve was obtained with the material pore diameter as the horizontal coordinate and the change rate of the pore volume with the pore diameter as the vertical coordinate, and the peak value in the curve was the most probable pore diameter.

[0041] The content of Ni and V in the oil product was determined by the standard method of GB / T 34099-2017.

[0042] The V+Ni removal rate% = (the metal V+Ni content of the raw oil - the metal V+Ni content of the product) / the metal V+Ni content of the raw oil x 100%.

[0043] Relative metal removal rate: the metal removal rate of a certain catalyst was determined, and the relative metal removal rate was defined as 100%, and the impurity removal rate of other catalysts was defined as the relative impurity removal rate.

[0044] Preparation of active metal modified sheet-like pseudo-boehmite material HP:

[0045] Example 1

[0046] (1) Take a certain amount of aluminum nitrate and place it in a crucible and calcine it at 550°C for 5.5 hours. The calcined material is then impregnated with an active component solution having a WO3 concentration of 2.1 g / 100 mL and a CoO concentration of 0.5 g / 100 mL for 1 hour. The impregnated material is then calcined at 500°C for 5 hours to produce an active metal modified aluminum oxide compound;

[0047] (2) The active metal modified aluminum oxide compound obtained in step (1) is ground to 100 mesh or more, and 100 grams of the sieved material is added to 650 grams of an aqueous propylene oxide solution having a mass concentration of 5.5%. The mixture is stirred magnetically for 30 minutes, and then the mixture is transferred to an autoclave and sealed. The mixture is heated at 130°C for 6.5 hours. After cooling, the solid material is filtered, washed, and dried at 120°C for 4 hours to produce an active metal modified sheet-like pseudoboehmite HP1. The microstructure of the sample is observed by scanning electron microscopy to be a sheet-like grain accumulation, and the sheet-like grain size is 125-680 nm and the thickness is 30-65 nm. The scanning electron micrograph is shown in Figure 1.

[0048] (2) The active metal modified aluminum oxide compound obtained in step (1) is ground to 100 mesh or more, and 100 grams of the sieved material is added to 650 grams of an aqueous propylene oxide solution having a mass concentration of 5.5%. The mixture is stirred magnetically for 30 minutes, and then the mixture is transferred to an autoclave and sealed. The mixture is heated at 130°C for 6.5 hours. After cooling, the solid material is filtered, washed, and dried at 120°C for 4 hours to produce an active metal modified sheet-like pseudoboehmite HP1. The microstructure of the sample is observed by scanning electron microscopy to be a sheet-like grain accumulation, and the sheet-like grain size is 125-680 nm and the thickness is 30-65 nm. The scanning electron micrograph is shown in Figure 1. Figure 1 .

[0049] Example 2

[0050] The same as Example 1, except that the calcination temperature of the aluminum nitrate in step (1) is 500°C, the calcination time is 6.5 hours, the WO3 concentration in the active component impregnation solution is 2.7 g / 100 mL, and the CoO concentration is 0.6 g / 100 mL. In step (2), the propylene oxide concentration is 6.6%, the solution amount is 570 grams, the hydrothermal treatment temperature is 140°C, and the treatment time is 5.5 hours. An active metal modified sheet-like pseudoboehmite HP2 is produced. The microstructure of the sample is observed by scanning electron microscopy to be a sheet-like grain accumulation, and the sheet-like grain size is 110-650 nm and the thickness is 25-60 nm.

[0051] Example 3

[0052] The same as Example 1, except that the calcination temperature of the aluminum nitrate in step (1) is 600°C, the calcination time is 4.5 hours, the WO3 concentration in the active component impregnation solution is 1.3 g / 100 mL, and the CoO concentration is 0.3 g / 100 mL. In step (2), the propylene oxide concentration is 4.4%, the solution amount is 740 grams, the hydrothermal treatment temperature is 100°C, and the treatment time is 7.5 hours. An active metal modified sheet-like pseudoboehmite HP3 is produced. The microstructure of the sample is observed by scanning electron microscopy to be a sheet-like grain accumulation, and the sheet-like grain size is 130-700 nm and the thickness is 30-65 nm.

[0053] Example 4

[0054] The same as Example 1, except that the calcination temperature of aluminum nitrate in step (1) is 450°C, the calcination time is 7.5 hours, the WO3 concentration in the active component impregnation solution is 3.2 g / 100 mL, and the CoO concentration is 0.8 g / 100 mL. In step (2), the propylene oxide concentration is 7.8%, the solution amount is 430 g, the hydrothermal treatment temperature is 155°C, and the treatment time is 4.5 hours. The active metal modified pseudoboehmite HP4 is prepared. The microstructure of the sample observed by scanning electron microscopy is a stack of sheet-shaped grains, the size of the sheet-shaped grains is 120-600 nm, and the thickness is 25-60 nm.

[0055] Comparative Example 1

[0056] The same as Example 1, except that the propylene oxide in step (2) is replaced by the same amount of ethylene oxide. No sheet-shaped grains are formed in the microstructure of the material HP5 after hydrothermal treatment.

[0057] Comparative Example 2

[0058] The same as Example 1, except that aluminum nitrate is replaced by aluminum sulfate in step (1). The particles of the solid material after hydrothermal treatment are dissolved, and no product is separated.

[0059] Comparative Example 3

[0060] The same as Example 1, except that aluminum nitrate is replaced by aluminum chloride in step (1). No sheet-shaped grains are formed in the microstructure of the material HP6 after hydrothermal treatment. The scanning electron microscopy image is shown in Figure 2 .

[0061] Comparative Example 4

[0062] The same as Example 1, except that no W and Co modification treatment is performed, i.e., no active component impregnation solution containing W and Co is used in step (1). The scanning electron microscopy image of the material after hydrothermal treatment is shown in Figure 3 .

[0063] Preparation of heavy oil hydrodemetallization catalyst:

[0064] Example 5

[0065] 50 g of the active metal modified sheet-shaped pseudoboehmite HP1 prepared in Example 1 is mixed with

[0066] 283 g of pseudoboehmite P2 (aluminum sulfate-sodium metaaluminate method, most probable pore size 13.5 nm) is mixed uniformly. The mixture is placed in a rotary table forming machine and mixed thoroughly. The inclination angle of the rotary table is adjusted to 43°, and the rotary speed of the rotary table is 15 rpm. A 1% acetic acid aqueous solution is sprayed onto the material in the rotary table by a sprayer. After mixing and contacting, the material is formed in the rotary table for 30 min. The spherical precursor S1 with a diameter of 2.0-3.0 mm is obtained.

[0067] (2) Take 100 grams of the active metal modified tabular pseudoboehmite HP1 prepared in Example 1 and 122 grams of the pseudoboehmite P2, mix them well, and then mix the mixture with the spherical precursor S1 prepared in step (1) in a rotary table forming machine. The inclination angle of the rotary table is adjusted to 40°, and the rotary speed of the rotary table is adjusted to 13 rpm. An aqueous acetic acid solution with a mass concentration of 1.2% is sprayed onto the mixture in the rotary table through a sprayer. After mixing and contacting, the mixture is formed in the rotary table for 25 min to obtain a spherical precursor S2 with a diameter of 4-5 mm.

[0068] (3) Put the active metal modified tabular pseudoboehmite HP1 prepared in Example 1 and the spherical precursor S2 prepared in step (2) in a rotary table forming machine and mix them well. The inclination angle of the rotary table is adjusted to 35°, and the rotary speed of the rotary table is adjusted to 12 rpm. An aqueous acetic acid solution with a mass concentration of 1.3% is sprayed onto the mixture in the rotary table through a sprayer. After mixing and contacting, the mixture is formed in the rotary table for 15 min to obtain a spherical material with a diameter of 6-8 mm. The obtained spherical material is dried at 120°C for 4 h and then calcined at 550°C for 4 h to obtain a spherical alumina carrier.

[0069] (4) Take 50 grams of the alumina carrier obtained in step (3) and impregnate the carrier with a Mo-Ni-P impregnation solution with a molybdenum oxide concentration of 7.6 g / 100 mL and a nickel oxide concentration of 2.1 g / 100 mL by using the equal-volume impregnation method. The impregnated material is dried at 120°C for 6 h and then calcined at 500°C for 4 h to obtain the hydrogen demetallization catalyst Cat-1 of the present application. The properties of the catalyst are shown in Table 1.

[0070] Example 6

[0071] The same as in Example 5, except that the active metal modified tabular pseudoboehmite HP1 in steps (1), (2), and (3) is replaced by the active metal modified tabular pseudoboehmite HP2, and the amount of the pseudoboehmite P2 added in step (1) is 200 grams and the amount of the pseudoboehmite P2 added in step (2) is 150 grams. The hydrogen demetallization catalyst Cat-2 of the present application is prepared, and the properties of the catalyst are shown in Table 1.

[0072] Example 7

[0073] The same as in Example 5, except that the active metal modified tabular pseudoboehmite HP1 in steps (1), (2), and (3) is replaced by the active metal modified tabular pseudoboehmite HP3, and the amount of the pseudoboehmite P2 added in step (1) is 367 grams and the amount of the pseudoboehmite P2 added in step (2) is 108 grams. The hydrogen demetallization catalyst Cat-3 of the present application is prepared, and the properties of the catalyst are shown in Table 1.

[0074] Example 8

[0075] The same as example 5, except that the active metal modified tabular pseudo-boehmite HP1 in step (1), step (2) and step (3) is replaced by active metal modified tabular pseudo-boehmite HP4, the adding amount of pseudo-boehmite P2 in step (1) is 177 grams, and the adding amount of pseudo-boehmite P2 in step (2) is 186 grams, to obtain the hydrodemetallization catalyst Cat-4 of the present application. The catalyst properties are shown in Table 1.

[0076] Comparative example 4

[0077] The same as example 5, except that the active metal modified tabular pseudo-boehmite HP1 in step (1), step (2) and step (3) is replaced by the material HP5 prepared in comparative example 1, to obtain the comparative hydrodemetallization catalyst Cat-5. The catalyst properties are shown in Table 1.

[0078] Comparative example 5

[0079] The same as example 5, except that the active metal modified tabular pseudo-boehmite HP1 in step (1), step (2) and step (3) is replaced by the material HP6 prepared in comparative example 3, to obtain the comparative hydrodemetallization catalyst Cat-6. The catalyst properties are shown in Table 1.

[0080] Comparative example 6

[0081] The same as example 5, except that the active metal modified tabular pseudo-boehmite HP1 in step (1), step (2) and step (3) is replaced by the material prepared in comparative example 4, and the same amount of active components is loaded on the alumina carrier by one-time impregnation, to obtain the comparative hydrodemetallization catalyst Cat-7. The catalyst properties are shown in Table 1.

[0082] Table 1 Catalyst properties

[0083] Example 5 Example 6 Example 7 Example 8 Comparative Example 4 Comparative Example 5 Comparative Example 6 Catalyst Cat-1 Cat-2 Cat-3 Cat-4 Cat-5 Cat-6 Cat-7 Specific surface area, m 2 / g]] 179 163 188 196 173 174 191 Pore volume, mL / g 0.89 0.88 0.91 0.93 0.77 0.83 0.91 MoO3content, wt% 7.8 7.6 7.6 7.5 7.7 7.9 7.8 NiO content, wt% 2.3 2.2 2.3 2.1 2.4 2.2 2.3 WO3 content, wt% 0.8 1.3 0.4 0.6 0.7 0.8 0.8 CoO content, wt% 0.2 0.4 0.1 0.2 0.3 0.2 0.3 10-20 nm pore content, v% 52.1 49.3 54.4 56.8 62.4 64.3 51.7 50-100 nm pore content, v% 16.4 18.1 14.3 11.9 7.3 5.8 15.9 Pore content greater than 100 nm, v% 15.1 17.3 13.9 12.4 2.7 2.6 14.3

[0084] The hydrodemetallization catalysts (Cat-1-Cat-6) prepared in the above examples and comparative examples are subjected to catalytic performance evaluation, and the evaluation method is as follows:

[0085] A certain residual oil is used as the raw material, the metal (Ni+V) content in the raw oil is 183 μg / g, the gum content is 57.2%, and the asphaltene content is 1.9%. The catalytic performance of the hydrodemetallization catalysts Cat-1-Cat-6 is evaluated on a 200 mL small evaluation device, and the reaction conditions are as follows: the reaction temperature is 375 ℃, the pressure is 14.5 MPa, the liquid hourly space velocity is 0.55 h-1, and the hydrogen to oil volume ratio is 750. The content of each impurity in the generated oil is measured after 500 hours and 3000 hours of reaction, the impurity removal rate is calculated, and the evaluation results are shown in Table 2. -1

[0086] Table 2 Catalyst hydrogenation performance comparison ​

[0087] Catalyst number Cat-1 Cat-2 Cat-3 Cat-4 Cat-5 Cat-6 Cat-7 Relative demetallization (V+Ni) rate at 500 hours, % 127 131 135 126 100 97 125 Relative demetallization (V+Ni) rate at 3000 hours, % 134 139 136 130 100 88 119

[0088] As can be seen from the data in Table 2, when the reaction time is 500 hours, the catalyst prepared by the method of the present application has higher hydrodemetallization activity compared with the comparative catalyst. When the reaction time is 3000 hours, the catalyst prepared by the method of the present application still has higher hydrodemetallization activity compared with the comparative catalyst, which shows that the hydrodemetallization catalyst has strong resistance to metal deposition and coke deposition, and is particularly suitable for use in the hydroprocessing of heavy residual oil with high content of metal (Ni, V), gum, asphaltene and the like.

Claims

1. A process for the preparation of a hydrodemetallation catalyst, characterized in that The method comprises the following steps: (1) roasting aluminum nitrate, and then impregnating the roasted material with an impregnation solution containing W and Co, drying and roasting to obtain a modified aluminum oxide compound; (2) crushing and sieving the modified aluminum oxide compound, and then sealing the sieved material in an epoxy propane solution for hydrothermal treatment, and then drying the treated material to obtain modified sheet-like pseudo-boehmite HP; (3) mixing pseudo-boehmite P2 and the modified sheet-like pseudo-boehmite HP to obtain a mixture H1, and then rolling the mixture H1 to form a spherical precursor S1; (4) mixing pseudo-boehmite P2 and the modified sheet-like pseudo-boehmite HP to obtain a mixture H2, and then mixing the spherical precursor S1 and the mixture H2 to continue rolling to form a spherical precursor S2; (5) mixing the modified sheet-like pseudo-boehmite HP and the spherical precursor S2, and then rolling to form a spherical precursor, and then drying and roasting to obtain a modified alumina carrier; (6) impregnating the modified alumina carrier with an impregnation solution containing Mo and Ni, and then drying and roasting the impregnated material to obtain a hydrodemetallization catalyst.

2. The method of claim 1, wherein: In step (1), the impregnation solution containing W and Co has a W concentration of 1 g / 100 mL to 3.5 g / 100 mL (calculated as WO3) and a Co concentration of 0.3 g / 100 mL to 1.0 g / 100 mL (calculated as CoO).

3. The method of claim 1, wherein: In step (2), the concentration of the epoxy propane solution is 2.5 wt% to 12 wt%, and the mass ratio of the epoxy propane solution to the modified aluminum oxide compound is 3:1 to 10:

1.

4. The method of claim 1, wherein: In step (2), the hydrothermal treatment is carried out in a sealed container at a temperature of 110-180°C for 4-8 hours under autogenous pressure.

5. The method of claim 1, wherein: In step (3), the mass ratio of the modified sheet-like pseudo-boehmite HP to the pseudo-boehmite P2 in the mixture H1 is 1:9 to 1:

3.

6. The method of claim 1, wherein: In step (4), the mass ratio of the modified sheet-like pseudo-boehmite HP to the pseudo-boehmite P2 is 3:7 to 1:

1.

7. The method of claim 1, wherein: In step (1), the roasting temperature of the aluminum nitrate is 450-650°C, and the roasting time is 4-8 hours. In step (2), the crushing is performed to a particle size of more than 100 mesh. In step (2), the concentration of the epoxy propane solution is 4 wt% to 8 wt%. In step (3), the pseudo-boehmite P2 is in a granular form, and the pore size of the pseudo-boehmite is greater than 10 nm. In step (3), the rolling is carried out on a rotating disc forming machine, and the rotating disc forming machine has an inclination angle of 40-70° and a rotating speed of 10-30 rpm. In step (3), the radius of the spherical precursor S1 is 0.2r to 0.5r, where r is the radius of the final modified alumina carrier, i.e., the straight-line distance from the center of the sphere to the outer surface.

8. The method of claim 1, wherein: The rolling ball forming in step (4) is carried out in a rotary table forming machine, and the rotary table forming machine has the following rotary operation conditions: the inclination angle of the rotary table is 40-70°, the rotary speed of the rotary table is 10-30 rpm, and the forming time of the material in the rotary table is 10-120 min; the radius of the spherical precursor S2 is 0.5r-0.9r, wherein r is the radius of the final modified alumina carrier, i.e. the straight-line distance from the center of the sphere to the outer surface.

9. The method of claim 1, wherein: The rolling ball forming in step (5) is carried out in a rotary table forming machine, and the rotary table forming machine has the following rotary operation conditions: the inclination angle of the rotary table is 40-70°, the rotary speed of the rotary table is 10-30 rpm, and the forming time of the material in the rotary table is 10-60 min, and the final sphere diameter is 5-10 mm.

10. The method of claim 1, wherein: The drying time in step (5) is 1-8 hours, the drying temperature is 60-180°C, the calcination temperature is 350-800°C, and the calcination time is 2-6 hours.

11. The method of claim 1, wherein: In the Mo and Ni-containing impregnating solution in step (6), the concentration of Mo is 5.5-12.5 g / 100 mL (calculated as MoO3), and the concentration of Ni is 1.4-3.2 g / 100 mL (calculated as NiO); equal-volume impregnation is adopted, and the drying conditions of the material after impregnation are 80-120°C for 4-8 hours, and the calcination conditions are 400-550°C for 4-8 hours.

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