A heavy oil hydrodemetallization catalyst and its preparation method

Abstract

This invention discloses a heavy oil hydrodemetallization catalyst and its preparation method. The catalyst includes an active metal component and an alumina support. The alumina support comprises lamellar alumina crystals and granular alumina crystals, wherein the mass ratio D of the active metal component content in the lamellar particle microregion to that in the spherical particle microregion, calculated as oxides, is 1.1-1.85. The catalyst preparation method is as follows: (1) Aluminum nitrate is calcined, pulverized, and sieved. The sieved material is then impregnated with an active component impregnation solution to obtain a modified material; (2) The modified material is immersed in a propylene oxide solution and subjected to closed heat treatment to obtain boehmite P1; (3) Boehmite P1 and boehmite P2 obtained in step (2) are used to prepare a support, and then the active metal component is loaded to obtain the heavy oil hydrodemetallization catalyst. The heavy oil hydrodemetallization catalyst of this invention has high activity and resistance to metal deposition.

Description

Technical Field

[0001] This invention belongs to the field of catalyst preparation, specifically relating to a heavy oil hydrodemetallization catalyst and its preparation method. Background Technology

[0002] In recent years, with the increasing weight of crude oil resources, the growing demand for fuel oil, and increasingly stringent environmental regulations, the use of hydrotreating technology to convert heavy oils, including residue oil, into high-quality fuel oils and chemical products has helped improve crude oil utilization, reduce environmental pollution, increase light oil yield, and improve product quality. Hydrodemetallization catalysts used for heavy oils, especially vacuum residue with high metal content, are prone to rapid activity decline and deactivation due to the deposition of metal impurities such as nickel and vanadium. Catalysts with larger pore volumes and diameters have strong metal and carbon holding capabilities, which can slow down catalyst deactivation and extend the catalyst's operating cycle. The pore structure of a catalyst is determined by the support it constitutes; therefore, preparing supports with larger pore volumes and diameters is key to preparing residue oil, especially for the hydrodemetallization of vacuum residue with high metal content.

[0003] Alumina is a commonly used catalyst support, widely applied in petroleum processing, chemical industry, and environmental protection. However, the pore diameter of alumina typically used in the preparation of hydrotreating catalysts, as well as commercially available alumina, is usually too small to meet the requirements for preparing catalysts for the hydrodemetallization and / or hydrodesulfurization of heavy oil and residual oil. Therefore, it is necessary to use a "pore enlargement" method during the support preparation process to increase its pore size.

[0004] CN201510191156.7 discloses a heavy oil hydrogenation catalyst and its preparation method. The catalyst comprises an alumina support composed of plate-like polycrystalline γ-alumina and a hydrogenation active metal. The preparation method of the catalyst is as follows: plate-like γ-polycrystalline alumina powder is added to a binder and an extrusion aid, kneaded, shaped, dried and calcined to obtain an alumina support, and an active metal is loaded onto the obtained alumina support using conventional methods. The preparation method of plate-like polycrystalline γ-alumina includes the following steps: (1) inorganic aluminum salt, low-carbon alcohol and / or water, and low-carbon epoxy alkane are mixed evenly to form a gel, and then the gel is aged; (2) the gel obtained in step (1) is soaked in low-carbon alcohol, and then dried and calcined; (3) the material obtained in step (2) is immersed in ammonia water for closed hydrothermal treatment, solid-liquid separation, and drying to obtain plate-like γ-polycrystalline alumina powder. This invention adjusts the pore structure of an alumina support by adding lamellar polycrystalline γ-alumina, but the preparation process of lamellar polycrystalline γ-alumina is relatively complex.

[0005] CN107913691A discloses a macroporous alumina carrier and its preparation method. The method involves first mixing boehmite powder and guar gum powder in a kneader until homogeneous. Then, a styrene-butadiene rubber (SBR) emulsion with a particle size of 10-500 nm is prepared, and an organic or inorganic acid is added to it. Next, the acid solution containing the SBR emulsion is added to the boehmite powder and guar gum powder and kneaded until homogeneous. After extrusion, molding, drying, and calcination, a macroporous alumina carrier is obtained. The alumina carrier prepared by this method has a pore size distribution of 60-400 nm. However, the preparation process of the styrene-butadiene rubber emulsion as a pore-expanding agent is relatively complex.

[0006] CN109718747A discloses a dual-porous alumina support, a dealmetallization catalyst, and a method for preparing the same. The dual-porous alumina support contains rod-shaped alumina clusters. The method for preparing the dual-porous alumina support includes: calcining boehmite A to obtain alumina; immersing the alumina in an ammonium bicarbonate aqueous solution for sealed heat treatment, drying, and then soaking in a polyethylene glycol solution; drying the soaked material to obtain rod-shaped alumina clusters; then mixing boehmite B with the obtained rod-shaped alumina clusters to form a mold; drying and calcining the molded material to obtain the dual-porous alumina support. This invention uses rod-shaped alumina clusters to adjust the pore structure of the alumina support and the dealmetallization catalyst; however, the catalytic activity of the catalyst at the macropores prepared by this method needs further improvement. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a heavy oil hydrodemetallization catalyst and its preparation method. This method uses active metal-modified lamellar boehmite as part of the raw material, adjusts the catalyst pore structure, improves the matching degree between the catalyst pore structure and the active metal, enhances the catalytic activity and utilization rate of the catalyst macropores, and has a simple preparation process. The prepared hydrodemetallization catalyst has high activity and resistance to metal deposition.

[0008] The heavy oil hydrodemetallization catalyst of the present invention comprises an active metal component and an alumina support, wherein the active metal component is a Group VIB and a Group VIII metal, and the alumina support comprises lamellar alumina crystals and granular alumina crystals. The mass ratio D of the active metal component content in the lamellar particle microregion to the active metal component content in the spherical particle microregion (based on oxides) is 1.1-1.85. More preferably, the mass ratio D1 of the Group VIB metal oxide content in the lamellar alumina crystal microregion to the Group VIB metal oxide content in the granular alumina crystal microregion (based on oxides) is 1.25-1.50, and the mass ratio D2 of the Group VIII metal in the lamellar alumina crystals to the Group VIII metal in the granular alumina crystal microregion (based on oxides) is 1.20-1.55.

[0009] In the heavy oil hydrodemetallization catalyst of the present invention, the size of the lamellar alumina crystals is 100-600 nm and the thickness is 15-40 nm, and the size of the granular alumina crystals is 20-100 nm.

[0010] In the heavy oil hydrodemetallization catalyst of the present invention, based on the weight of the hydrodemetallization catalyst, the content of the active metal component, calculated as oxide, is 8%-20%, and the alumina support is 80%-92%; preferably, the content of Group VIB metals, calculated as metal oxides, is 6.5wt%-12.5wt%, and the content of Group VIII metals, calculated as metal oxides, is 1.5wt%-4.5wt%; more preferably, the Group VIB metals are selected from W and / or Mo, and the Group VIII metals are selected from Co and / or Ni.

[0011] The heavy oil hydrodemetallization catalyst of this invention has a specific surface area of ​​160-240 m². 2 / g, with a pore volume of 0.65-1.1mL / g, and most probable pore sizes of 10-20nm and 50-100nm. The pores of 10-20nm account for 40%-60% of the total pore volume, and the pores of 50-100nm account for 10%-25% of the total pore volume.

[0012] The preparation method of the heavy oil hydrodemetallization catalyst of the present invention includes the following steps:

[0013] (1) Aluminum nitrate is roasted, crushed and sieved. The sieved material is impregnated with active component impregnation solution. The impregnated material is dried and roasted to obtain modified material.

[0014] (2) The modified material was immersed in a propylene oxide solution and heat-treated in a sealed manner. After treatment, the material was dried to obtain active metal modified flaky boehmite P1.

[0015] (3) The active metal modified sheet-like pseudoboehmite P1 and pseudoboehmite P2 from step (2) are mixed and kneaded to prepare a support, and then the active metal component is loaded to obtain a heavy oil hydrodemetallization catalyst.

[0016] In the method of the present invention, the calcination temperature of aluminum nitrate in step (1) is 450-650℃, the calcination time is 4-8 hours, and the particle size of the material is greater than 100 mesh, preferably greater than 200 mesh.

[0017] In the method of the present invention, the active component impregnation solution in step (1) is a solution containing Group VIB and Group VIII metals, preferably W and / or Mo for Group VIB and Co and / or Ni for Group VIII. The impregnation solution is prepared in a manner well known to those skilled in the art, such as using a phosphoric acid solution of W and / or Mo and Co and / or Ni, wherein the concentration of WO3 and / or MoO3 in the solution is 1.5-4 g / 100 mL and the concentration of CoO and / or NiO is 0.5-1.2 g / 100 mL, the amount of impregnation solution used is such that the material after sieving is completely submerged, and the impregnation time is 0.5-2 hours; the drying temperature is 80-140℃ and the drying time is 4-10 hours; the calcination temperature is 400-550℃ and the calcination time is 4-10 hours.

[0018] In the method of the present invention, the concentration of the propylene oxide solution in step (2) is 2.5wt%-12wt%, preferably 4wt%-8wt%, and the mass ratio of the propylene oxide solution to the modified material is 3:1-10:1, preferably 4:1-8:1.

[0019] In the method of this invention, the sealed heat treatment in step (2) is generally carried out in a sealed container, preferably an autoclave. The sealed heat treatment temperature is 110-180℃, preferably 120-160℃, and the sealed heat treatment time is 4-8 hours. During the sealed heat treatment, the pressure inside the sealed container is self-generated pressure. The drying temperature is 100-160℃, and the drying time is 2-8 hours.

[0020] In the method of the present invention, the pseudoboehmite P2 mentioned in step (3) can be granular pseudoboehmite prepared by existing methods, such as acid precipitation, alkali precipitation, aluminum alkoxide hydrolysis, etc., preferably spherical particles, more preferably pseudoboehmite with a pore size of 10-20 nm, and more preferably pseudoboehmite with a pore volume of 10-20 nm accounting for more than 50% of the total pore volume.

[0021] In the method of the present invention, the mass ratio of active metal modified boehmite P1 to boehmite P2 in step (3) is 1:4-1:1.

[0022] In the method of this invention, the kneading and molding in step (3) is carried out using conventional methods in the art. During the molding process, conventional molding aids, such as adhesives, extrusion aids, etc., can be added as needed. The adhesive is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, oxalic acid, etc., and the mass percentage concentration of the adhesive is 0.5%-2%. The amount of adhesive used depends on the molding effect. The extrusion aid is guar gum powder, and the amount added is 1%-3% of the final alumina carrier weight.

[0023] In the method of the present invention, the carrier preparation process described in step (3) generally includes drying and calcining the shaped material. The general drying temperature is 100-160℃, the drying time is 6-10 hours, the calcination temperature is 450-750℃, preferably 500-600℃, and the calcination time is 4-6 hours.

[0024] In the method of this invention, the loading process in step (3) is carried out by impregnation. The alumina support is impregnated with an active metal component impregnation solution. The impregnated support is dried and calcined to obtain a hydrogenation demetallization catalyst. The active metal component impregnation solution is a solution containing Group VIB metals and Group VIII metals. The Group VIB metal is Mo and / or W, preferably Mo, and the Group VIII metal is Ni and / or Co, preferably Ni. The content of the Group VIB metal, calculated as oxides, is 6-16 g / 100 mL, and the content of the Group VIII metal, calculated as oxides, is 0.5-4.5 g / 100 mL. The active component impregnation solution can be an ammonia solution, an aqueous solution, or a phosphoric acid solution of the Group VIB metal and Group VIII metal, preferably a phosphoric acid solution containing the Group VIB metal and Group VIII metal. The drying and calcination conditions are well known to those skilled in the art and are generally: drying temperature 100-160℃, drying time 6-10 hours; calcination temperature 450-550℃, calcination time 4-6 hours.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] (1) The method of the present invention first prepares active metal modified boehmite P1. The boehmite crystals are plate-like structures with large crystal size and interwoven stacking of plate-like crystals to form a large number of macropores. During the extrusion molding of the carrier, the plate-like particles support each other, so that the macropores formed are relatively intact, ensuring the macropore content of the final carrier and catalyst, which is beneficial to the diffusion of macromolecular reactants in the reaction raw materials.

[0027] (2) The present invention uses plate-like pseudoboehmite modified with active metal as part of the raw material to prepare a hydrogenation demetallization catalyst. The catalyst has a high content of active metal in the macropores formed by the accumulation of plate particles, which improves the catalytic activity of the macropores in the catalyst. Furthermore, the high-activity sites of the catalyst are well matched with the pores, and the high-activity sites have strong resistance to metal deposition. While ensuring the high activity of the catalyst, it also has high activity stability.

[0028] (3) The active metal modified flaky boehmite used in this invention is obtained by hydrothermal treatment of aluminum compounds containing active metals in propylene oxide solution. During hydrothermal treatment, the active metal component grows secondary along with the aluminum compound, which can improve the strong interaction between the active metal and the final alumina support and enhance the catalyst activity. Attached Figure Description

[0029] Figure 1 is a SEM image of the sample prepared in Example 1.

[0030] Figure 2 shows the SEM image of the sample prepared in Comparative Example 3.

[0031] Figure 3 shows the SEM image of the sample prepared in Comparative Example 4. Implementation

[0032] The technical solution and effects of the present invention will be further illustrated below with reference to the embodiments, but the invention is not limited to the following embodiments. In the present invention, wt% represents mass fraction.

[0033] BET Method: The pore structure of the carriers in the examples and comparative examples was characterized using N2 physical adsorption-desorption. The specific procedure was as follows: The pore structure of the samples was characterized using an ASAP-2420 N2 physical adsorption-desorption instrument. A small amount of sample was vacuum-treated at 300℃ for 3-4 hours, and finally, the product was placed under liquid nitrogen cryogenic conditions (-200℃) for nitrogen adsorption-desorption testing. The specific surface area was obtained according to the BET equation, and the pore volume and pore diameter distribution below 30nm were obtained according to the BJH model.

[0034] Mercury porosimetry: The pore diameter distribution of the carriers in the examples and comparative cases was characterized using a mercury porosimetry instrument. The specific procedure was as follows: The pore distribution of the samples was characterized using a Micron AutoPore 9500 fully automated mercury porosimetry instrument. After drying, the samples were weighed and placed into a dilatometer. The sample was then degassed for 30 minutes under the vacuum conditions specified by the instrument before mercury was added. The dilatometer was then placed in an autoclave, and the pressure was evacuated. Pressure increase and decrease tests were then performed. The mercury contact angle was 130°, and the mercury interfacial tension was 0.485 N / cm. -1 The distribution rate of pores with a diameter of 100 nm or more was measured by mercury porosimetry.

[0035] The microstructure of the sample was characterized using a scanning electron microscope (SEM). The specific operation was as follows: The microstructure of the carrier was characterized using a JSM-7500F SEM with an accelerating voltage of 5 kV, an accelerating current of 20 µA, and a working distance of 8 mm.

[0036] The micro-region composition of the sample was characterized using a scanning electron microscope-energy dispersive spectroscopy (SEM-EDAX) instrument. The specific procedures were as follows: A JSM-7500F SEM equipped with an EDAX spectrometer was used, with an accelerating voltage of 30 kV, a probe current of 11 µA, and a working distance of 8 mm. Twenty micro-regions with both plate-like and spherical particle packing were selected as measurement areas. The contents of Group VIB and Group VIII metal oxides in the corresponding areas were measured, and the average values ​​were used to calculate the D1 and D2 values.

[0037] The molybdenum-nickel content in the bulk catalyst was determined according to the method described in the literature, ICP-AES determination of metal element content in molybdenum-nickel series hydrogenation catalysts, Guangzhou Chemical Industry, 2021, 49, (17): 129-130.

[0038] The cobalt content in the bulk catalyst was determined according to the standard SHT0345-1992 - Determination of Cobalt Content in Hydrorefining Catalysts.

[0039] The tungsten content in the bulk catalyst was determined according to the method described in the literature, "Determination of Tungsten Content in Hydrogenation Catalysts by Thiocyanate Spectrophotometry", Physical and Chemical Testing - Chemical Section, 2003, 39(1): 51-53.

[0040] The Ni and V content in oil products was determined using the standard method of GB / T 34099-2017.

[0041] V+Ni removal rate % = (V+Ni content in feedstock oil - V+Ni content in product oil) / V+Ni content in feedstock oil × 100%.

[0042] Relative demetallization rate: The demetallization rate of a catalyst is measured, and its relative demetallization rate is defined as 100%. The relative impurity removal rate is calculated as the ratio of the impurity removal rate of other catalysts to the defined impurity removal rate of the catalyst × 100%.

[0043] Preparation of active metal-modified platy boehmite: Example 1

[0044] (1) Weigh an appropriate amount of aluminum nitrate and place it in a crucible. Calcinate the material at 550°C for 5 hours. The calcined material is then powdered.

[0045] Crushed and sieved to obtain particles larger than 200 mesh;

[0046] (2) Weigh an appropriate amount of the above material powder, and impregnate the powder for 1 hour with a Mo-Ni-P impregnation solution with a molybdenum oxide concentration of 3g / 100mL and a nickel oxide concentration of 0.8g / 100mL. After impregnation, filter the material, dry it at 120℃ for 6 hours, and calcine it at 450℃ for 6 hours.

[0047] (3) Weigh 100 grams of the material after roasting in step (2) and add 5.4% propylene oxide.

[0048] 670 g of aqueous solution was magnetically stirred for 30 minutes, then the mixture was transferred to an autoclave, sealed, and heated at 135°C for 6.5 hours. After cooling, the solid material was filtered, washed, and dried at 120°C for 4 hours to obtain the active component-modified pseudoboehmite P1-1. The microstructure of the sample was a stacked plate-like grain, with a grain size of 150-550 nm and a thickness of 15-30 nm. The scanning electron microscope image of the sample is shown below. Figure 1 . Example 2

[0049] Same as Example 1, except that in step (1), the calcination temperature of aluminum nitrate is 500℃ and the calcination time is 6 hours. In step (2), the concentration of molybdenum oxide in the active component impregnation solution is 3.5g / 100mL, the concentration of nickel oxide is 0.9g / 100mL, the concentration of propylene oxide is 6.5%, the solution volume is 550g, the hydrothermal treatment temperature is 145℃, and the treatment time is 5.5 hours, thus obtaining the active component modified boehmite P1-2. The microstructure of the sample is a stack of lamellar grains with a size of 120-540nm and a thickness of 15-35nm. Example 3

[0050] Same as Example 1, except that in step (1), the calcination temperature of aluminum nitrate is 600℃ and the calcination time is 4 hours. In step (2), molybdenum oxide in the active component impregnation solution is replaced with tungsten oxide at a concentration of 2.5 g / 100 mL, nickel oxide is replaced with cobalt oxide at a concentration of 0.6 g / 100 mL, the concentration of propylene oxide is 7.5%, the solution volume is 430 g, the hydrothermal treatment temperature is 155℃, and the treatment time is 4.5 hours, thus obtaining active component modified boehmite P1-3. The microstructure of the sample is a stack of lamellar grains with a size of 150-560 nm and a thickness of 15-35 nm. Example 4

[0051] Same as Example 1, except that in step (1), the calcination temperature of aluminum nitrate is 450℃ and the calcination time is 7 hours. In step (2), the concentration of molybdenum oxide in the active component impregnation solution is 1.8 g / 100 mL, the concentration of nickel oxide is 0.5 g / 100 mL, the concentration of propylene oxide is 4.4%, the solution volume is 760 g, the hydrothermal treatment temperature is 125℃, and the treatment time is 7.5 hours, thus obtaining the active component modified boehmite P1-4. The microstructure of the sample is a stack of lamellar grains with a size of 120-500 nm and a thickness of 15-30 nm.

[0052] Comparative Example 1

[0053] Same as Example 1, except that in step (3) propylene oxide is replaced with the same amount of ethylene oxide. After hydrothermal treatment, no lamellar grains were observed to form in the microstructure of material P1-5.

[0054] Comparative Example 2

[0055] Same as Example 1, except that aluminum nitrate is replaced with aluminum sulfate in step (1). After hydrothermal treatment, the solid material particles dissolve and are not separated to obtain the product.

[0056] Comparative Example 3

[0057] Same as Example 1, except that aluminum nitrate was replaced with aluminum chloride in step (1). After hydrothermal treatment, no lamellar grains were observed in the microstructure of material P1-6. The scanning electron microscope image of the sample is shown below. Figure 2 .

[0058] Comparative Example 4

[0059] Same as Example 1, except that the material powder in step (2) was replaced with γ-alumina powder of the same mesh size. After hydrothermal treatment, the material P1-7 was obtained. The scanning electron microscope image of the sample is shown below. Figure 3 .

[0060] Comparative Example 5

[0061] Same as Example 1, except that the hydrothermal treatment time in step (3) is 1.5 hours, and no lamellar grains are observed in the microstructure of material P1-8 after hydrothermal treatment.

[0062] Preparation of hydrogenation demetallization catalysts Example 5

[0063] (1) Weigh 100 g of active metal-modified boehmite P1-1 prepared in Example 1, 230 g of boehmite P2 (produced by Wenzhou Jingjing Alumina Co., Ltd., with 10-20 nm pore volume accounting for 58% of the total pore volume), and 0.5 g of guar gum powder. Mix the above materials evenly, add an appropriate amount of 1% acetic acid aqueous solution and knead, extrude into strips, dry the strips at 140°C for 6 hours, and calcine the dried material in air at 550°C for 5 hours to obtain an alumina support. Use a scanning electron microscope equipped with an energy dispersive spectroscopy (EDS) to determine the micro-region composition of the lamellar grains in the support. The MoO3 content in this micro-region is 3.2%, and the NiO content is 0.9%.

[0064] (2) Weigh 50 g of the above alumina support and impregnate the alumina support with a Mo-Ni-P active component impregnation solution with a molybdenum oxide concentration of 7.2 g / 100 mL and a nickel oxide concentration of 2.1 g / 100 mL in a saturated impregnation manner. The impregnated material is dried at 120 °C for 6 hours and the dried material is calcined in air at 500 °C for 5 hours to obtain the hydrogenation demetallization catalyst Cat-1. The properties of the catalyst are shown in Table 1. Example 6

[0065] Same as Example (5), except that the active metal modified boehmite P1-1 was replaced with P1-2, and the amount of boehmite P2 added was 166 grams, to obtain an alumina support. The MoO3 content in the micro-regions of the lamellar grains in the alumina support was 3.4%, and the NiO content was 1.1%. The hydrogenation demetallization catalyst Cat-2 was obtained, and the properties of the catalyst are shown in Table 1. Example 7

[0066] Same as Example (5), except that the active metal modified boehmite P1-1 is replaced with P1-3, and the amount of boehmite P2 added is 125 grams, to obtain an alumina support. The WO3 content in the micro-regions of the lamellar grains in the alumina support is 2.6%, and the CoO content is 0.6%. The hydrogenation demetallization catalyst Cat-3 was obtained, and the properties of the catalyst are shown in Table 1. Example 8

[0067] Same as Example (5), except that the active metal modified boehmite P1-1 is replaced with P1-4, and the amount of boehmite P2 added is 340 grams, to obtain an alumina support. The MoO3 content in the micro-regions of the lamellar grains in the alumina support is 1.9%, and the NiO content is 0.5%. The hydrogenation demetallization catalyst Cat-4 was obtained, and the properties of the catalyst are shown in Table 1.

[0068] Comparative Example 4

[0069] Same as Example (5), except that the active metal modified pseudoboehmite P1-1 was replaced with P1-5, and no micro-regions containing plate-like crystal grains were observed in the support. The comparative hydrogenation demetallization catalyst Cat-5 was prepared, and the catalyst properties are shown in Table 1.

[0070] Comparative Example 5

[0071] Same as Example (5), except that the active metal modified pseudoboehmite P1-1 was replaced with P1-6, and no micro-regions containing plate-like crystal grains were observed in the support. The comparative hydrogenation demetallization catalyst Cat-6 was prepared, and the catalyst properties are shown in Table 1.

[0072] Comparative Example 6

[0073] Same as Example (5), except that the active metal modified pseudoboehmite P1-1 was replaced with P1-7 to prepare the comparative hydrogenation demetallization catalyst Cat-7. The properties of the catalyst are shown in Table 1.

[0074] Comparative Example 7

[0075] Same as Example (5), except that the active metal modified pseudoboehmite P1-1 was replaced with P1-8, and no micro-regions containing plate-like crystal grains were observed in the support, thus preparing the comparative hydrogenation demetallization catalyst Cat-6. The catalyst properties are shown in Table 1.

[0076] Table 1 Catalyst Properties

[0077] Example 5 Example 6 Example 7 Example 8 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 catalyst Cat-1 Cat-2 Cat-3 Cat-4 Cat-5 Cat-6 Cat-7 Cat-8 <![CDATA[Specific surface area, m 2 / g]]> 206 187 165 220 173 158 191 183 Pore ​​volume, mL / g 0.93 0.91 0.88 0.95 0.81 0.79 0.86 0.83 10-20nm pore content, % 53.7 51.4 49.6 56.3 60.4 58.7 50.3 59.7 50-100nm pore content, % 15.6 18.3 22.1 11.7 3.3 4.1 7.3 6.2 D1 1.47 1.49 1.32 1.27 — — 1.46 — D2 1.45 1.54 1.31 1.26 — — 1.44 — <![CDATA[MoO3 content, wt%]]> 8.3 8.6 7.3 7.7 8.4 8.3 8.3 8.4 <![CDATA[WO3 content, wt%]]> — — 1.2 — — — — — NiO content, wt% 2.4 2.6 2.3 2.3 2.5 2.4 2.5 2.4 Co content, wt% — — 0.3 — — — — —

[0078] The catalytic performance of the hydrogenation demetallization catalysts (Cat-1-Cat-8) prepared in the above examples and comparative examples was evaluated using the following methods:

[0079] Using a certain residue oil as feedstock, with a metal (Ni+V) content of 179 μg / g, the catalytic performance of the hydrodemetallization catalyst Cat-1-Cat-8 was evaluated on a 200 mL small-scale evaluation device under the following conditions: reaction temperature 380℃, pressure 14.0 MPa, and liquid hourly space velocity 0.6 h⁻¹. -1 The hydrogen-to-oil volume ratio was 800. The content of each impurity in the generated oil was measured after 500 hours and 2000 hours of reaction, and the impurity removal rate was calculated. The evaluation results are shown in Table 2.

[0080] Table 2 Comparison of catalyst hydrogenation performance

[0081] Catalyst number Cat-1 Cat-2 Cat-3 Cat-4 Cat-5 Cat-6 Cat-7 Cat-8 Relative demetallization (V+Ni) rate after 500 hours, % 134 137 141 129 100 98 118 112 Relative demetallization (V+Ni) rate over 3000 hours, % 131 138 146 132 100 81 120 119

[0082] As shown in Table 2, when the reaction time is 500 hours, the hydrodemetallization catalyst of this invention exhibits higher activity compared to the comparative catalyst; when the reaction time is 3000 hours, the hydrodemetallization catalyst prepared by the method of this invention still exhibits higher activity compared to the comparative catalyst. This indicates that the catalyst prepared by the method of this invention has high hydrodemetallization activity and activity stability.

Claims

1. A heavy oil hydrodemetallization catalyst, characterized in that: The alumina carrier comprises an active metal component and an alumina support. The active metal component consists of Group VIB and Group VIII metals. The alumina support includes lamellar alumina grains and granular alumina grains. The mass ratio (D) of the active metal component content (based on oxides) in the micro-regions of lamellar alumina grains to that in the micro-regions of granular alumina grains is 1.1-1.

85. The mass ratio (D1) of the Group VIB metal oxide content (based on oxides) in the micro-regions of lamellar alumina grains to that in the micro-regions of granular alumina grains is 1.25-1.

50. The mass ratio (D1) of the Group VIB metal oxide content (based on oxides) in the micro-regions of lamellar alumina grains is [missing information]. The mass ratio (D2) of Group VIII metals (based on oxides) in the micro-regions of the metal and granular alumina grains is 1.20-1.55; based on catalyst weight, the content of the active metal component (based on oxides) is 8%-20%, and the alumina support is 80%-92%; the content of Group VIB metals (based on metal oxides) is 6.5wt%-12.5wt%, and the content of Group VIII metals (based on metal oxides) is 1.5wt%-4.5wt%; the Group VIB metals are selected from W and / or Mo, and the Group VIII metals are selected from Co and / or Ni; the specific surface area of ​​the catalyst is 160-240 m². 2 / g, pore volume is 0.65-1.1mL / g, most probable pore size is 10-20nm and 50-100nm, of which 10-20nm pores account for 40%-60% of the total pore volume and 50-100nm pores account for 10%-25% of the total pore volume; the preparation method of the heavy oil hydrodemetallization catalyst includes the following: (1) calcining, pulverizing and sieving aluminum nitrate, impregnating the sieved material with an active metal component impregnation solution, and drying and calcining the impregnated material to obtain the modified material; ( 2) The modified material is immersed in propylene oxide solution for closed heat treatment. After treatment, the material is dried to obtain active metal modified flake pseudoboehmite P1; (3) The active metal modified flake pseudoboehmite P1 and pseudoboehmite P2 in step (2) are mixed and kneaded to prepare a carrier, and then the active metal component is loaded to obtain a heavy oil hydrogenation demetallization catalyst; the closed heat treatment temperature in step (2) is 110-180℃, the closed heat treatment time is 4-8 hours, and the pressure inside the sealed container during the closed heat treatment is the self-generated pressure.

2. The heavy oil hydrodemetallization catalyst according to claim 1, characterized in that: The lamellar alumina has a grain size of 100-600 nm and a thickness of 15-40 nm; the granular alumina has a grain size of 20-100 nm.

3. A method for preparing the heavy oil hydrodemetallization catalyst according to claim 1 or 2, characterized in that... The process includes the following: (1) calcining, crushing, and sieving aluminum nitrate, then impregnating the sieved material with an active metal component impregnation solution, and then drying and calcining the impregnated material to obtain a modified material; (2) immersing the modified material in a propylene oxide solution for closed heat treatment, and then drying the treated material to obtain active metal modified flake boehmite P1; (3) mixing and molding the active metal modified flake boehmite P1 and boehmite P2 from step (2) into a carrier, and then loading the active metal component to obtain a heavy oil hydrodemetallization catalyst.

4. The method according to claim 3, characterized in that: The calcination temperature of aluminum nitrate in step (1) is 450-650℃, the calcination time is 4-8 hours, and the particle size of the material is greater than 100 mesh.

5. The method according to claim 3, characterized in that: The active metal component impregnation solution in step (1) is a solution containing Group VIB and Group VIII metals. The amount of impregnation solution used is such that the material after sieving is completely submerged. The impregnation time is 0.5-2 hours. The drying temperature is 80-140℃ and the drying time is 4-10 hours. The calcination temperature is 400-550℃ and the calcination time is 4-10 hours.

6. The method according to claim 3, characterized in that: The concentration of the propylene oxide solution in step (2) is 2.5wt%-12wt%, and the mass ratio of the propylene oxide solution to the modified material is 3:1-10:

1.

7. The method according to claim 3, characterized in that: The concentration of the propylene oxide solution in step (2) is 4wt%-8wt%, and the mass ratio of the propylene oxide solution to the modified material is 4:1-8:

1.

8. The method according to claim 3, characterized in that: The temperature of the sealed heat treatment in step (2) is 110-180℃, the time is 4-8 hours, and the pressure inside the sealed container during the sealed heat treatment is the self-generated pressure.

9. The method according to claim 3, characterized in that: The pseudoboehmite P2 mentioned in step (3) is a spherical particle with a pore size of 10-20 nm, and the pore volume of 10-20 nm accounts for more than 50% of the total pore volume.

10. The method according to claim 3, characterized in that: The mass ratio of active metal-modified boehmite P1 to boehmite P2 in step (3) is 1:4-1:

1.

11. The application of the heavy oil hydrodemetallization catalyst according to claim 1 or 2 in the field of heavy oil hydrotreating.

Images