Hydrodemetallization catalyst, method for preparing the same, and use thereof

Abstract

The application provides a hydrodemetallization catalyst and a preparation method and application thereof. The catalyst comprises a carrier and a second active metal, the carrier comprises alumina, activated carbon and a first active metal, and the mass ratio of the alumina to the activated carbon is 4-12:1. The catalyst is used in a residual oil hydrodemetallization process, has high hydrodemetallization activity and metal capacity, and can ensure long-period operation of a device.

Description

Technical Field

[0001] This invention relates to a hydrodemetallization catalyst, specifically to a hydrodemetallization catalyst suitable for the hydrotreating process of residual oil, its preparation method, and its application. Background Technology

[0002] In recent years, crude oil resources have become increasingly scarce, and the trend of heavy and inferior crude oil has intensified. Many refineries are adapting to economic development and seeking effective methods to convert heavy oil into lighter products. Hydrotreating technology, as an important route for converting heavy oil into lighter products, also faces new challenges and problems under the current circumstances. Residue hydrotreating technology is a crucial means of converting heavy oil into lighter products in the petroleum refining process, and its development hinges on the research and development of catalysts with good activity and stability. Hydrodemetallization catalysts, positioned before hydrodesulfurization and decarbonization agents, play a vital role in removing various metallic impurities (mainly Ni and V) from the feedstock, thus ensuring the overall effectiveness of the hydrotreating process. Therefore, developing hydrodemetallization catalysts with suitable activity and good stability is particularly important.

[0003] CN105709765A discloses a method for preparing a hydrodemetallization catalyst for residual oil, comprising the following steps: (1) mixing a pore-expanding agent, boehmite dry powder, extrusion aid, and adhesive solvent into a plastic body, extruding and drying; (2) spraying the unsaturated carrier after drying in step (1) with a mixed solution of phosphoric acid and ammonium oxalate, subjecting the impregnated carrier to sealed heating treatment, with the treatment pressure being the self-generated pressure under sealed conditions, the treatment temperature being 120-160℃, and the treatment time being 6-12 hours, and the treated carrier being dried and calcined to obtain an alumina carrier; (3) impregnating the alumina prepared in step (2) with active components, and after impregnation, drying and calcining to obtain an alumina carrier for the hydrodemetallization catalyst of residual oil.

[0004] CN1206037A discloses a catalyst for the hydrodemetallization of residue oil. The method of this invention is characterized by the simultaneous addition of physical and chemical pore-expanding agents during the preparation of the alumina support, followed by loading the active component onto the support via spray impregnation. The catalyst has a pore volume of 0.80–1.20 mL / g and a specific surface area of ​​110–200 m². 2 / g, with a pore size of 15-20nm.

[0005] CN1289640A discloses a method for preparing a supported hydrodemetallization catalyst. The method includes taking a macroporous δ- and / or θ-phase alumina support, placing it in a spray-impregnation boiler, preparing a Group VIB metal compound and / or Group VIII metal compound into an ammonia solution or aqueous solution, and uniformly spraying it onto the support in an atomized manner. The sprayed catalyst is then directly fed into a calcination furnace at a temperature of 300-450℃, and then gradually heated to 460-550℃, maintaining this temperature for 1-5 hours in the presence of air.

[0006] The activity and stability of the hydrogenation demetallization catalysts prepared by the above method still need to be further improved. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a hydrodemetallization catalyst, its preparation method, and its application. This catalyst, used in the hydrodemetallization process of residue oil, exhibits high hydrodemetallization activity and metal-containing capacity, ensuring long-term operation of the equipment.

[0008] The first aspect of the present invention provides a hydrodemetallization catalyst, the catalyst comprising a support and a second active metal, the support comprising alumina, activated carbon and a first active metal, wherein the mass ratio of alumina to activated carbon is 4 to 12:1, preferably 6 to 9:1.

[0009] In this invention, the first active metal is at least one of Group VIII metals, preferably nickel. The second active metal includes molybdenum (the primary active metal) and at least one selected from Group VIII metals (a secondary active metal), wherein the Group VIII metal is preferably nickel.

[0010] In this invention, based on the mass of the catalyst, the content of MoO3 is 9.0% to 35.0%, and the content of Group VIII metal oxides is 5.0% to 16.0%.

[0011] In this invention, the content of Group VIII metals in the first active metal as oxides is 30.0% to 60.0% of the total Group VIII metal oxide loading in the catalyst, and the content of Group VIII metals in the second active metal as oxides is 40.0% to 70.0% of the total Group VIII metal oxide loading in the catalyst.

[0012] In this invention, the catalyst has a specific surface area of ​​140–210 m². 2 / g, with a pore volume of 0.50–1.25 mL / g; preferably, the catalyst has a specific surface area of ​​150–180 m² / g. 2 / g, with a pore volume of 0.70~1.00mL / g.

[0013] In this invention, the catalyst further includes an auxiliary component, which is selected from at least one of fluorine, phosphorus, silicon, or boron, preferably phosphorus. Based on the mass of the catalyst, the content of the auxiliary component, calculated as oxides, is 2.0% to 11.0%.

[0014] A second aspect of this invention provides a method for preparing the above-mentioned hydrogenation demetallization catalyst, comprising the following steps:

[0015] (1) Activated carbon is impregnated with a first active metal impregnation solution containing a dispersant, and then dried and calcined to obtain modified activated carbon A;

[0016] (2) The modified activated carbon A obtained in step (1) is mixed with an alkaline additive, ground and dried to obtain modified activated carbon B.

[0017] (3) Mix the pseudoboehmite, the modified activated carbon B obtained in step (2), and the adhesive, shape them, and then dry and calcinate them to obtain the carrier C;

[0018] (4) Carrier C is subjected to surface carbonization treatment, and then dried and calcined to obtain carrier D;

[0019] (5) Impregnate the carrier D obtained in step (4) with the second active metal impregnation solution, let it stand, and obtain the catalyst precursor;

[0020] (6) The catalyst precursor obtained in step (5) is dried and calcined to obtain the hydrogenation demetallization catalyst.

[0021] In step (1), the dispersing agent is silica sol. The silica sol contains 20.0% to 50.0% silica by mass.

[0022] In step (1), the first active metal is at least one of Group VIII metals, preferably nickel, and the nickel source is selected from at least one of basic nickel carbonate, nickel nitrate, and nickel sulfate. Further, in the first active metal impregnation solution, the mass content of the first active metal oxide is 2.0% to 15.0%, and the mass content of the dispersing agent, calculated as silica, is 0.5% to 5.0%.

[0023] In step (1), the activated carbon is high-temperature activated carbon. The minimum heat resistance temperature of the high-temperature activated carbon is 750℃. The particle size of the activated carbon is 0.1~6.0μm.

[0024] In step (1), the impregnation method is saturated impregnation.

[0025] In step (1), the drying conditions are: temperature of 120-180℃ and drying time of 4-8h. The calcination conditions are: temperature of 550-750℃ and time of 3-8h, and the calcination atmosphere is one or more of air, water vapor, and nitrogen.

[0026] In step (1), the first active metal (Ni) is a co-active metal, which can interact with the support during the calcination process to weaken the acidity of the support, and can also work synergistically with the main active metal (Mo) in the second active metal component, which is beneficial to the hydrogenation reaction.

[0027] In step (2), the alkaline auxiliary agent is one or more of the following alkaline compounds: sodium hydroxide, potassium hydroxide, sodium carboxylate (such as sodium acetate, sodium formate, etc.).

[0028] In step (2), the mass ratio of the alkaline additive to the activated carbon used in step (1) is 0.01 to 0.10.

[0029] In step (2), the grinding can be carried out by ball milling, sand milling, or other methods. The ground material not only has a more uniform metal dispersion, but the alkaline additive will also form a "first protective film" on the surface of the dried material during the molding process in step (3). After grinding, a ground sample with an average particle size of 2.0 to 8.0 μm is obtained.

[0030] In step (2), the drying conditions are: temperature of 120-180℃ and drying time of 4-8h.

[0031] In step (3), the pseudoboehmite is obtained by conventional methods, such as the aluminum sulfate method, aluminum alkoxide method, sol-gel method, etc. The alumina content in the pseudoboehmite is 65.0% to 80.0% by mass.

[0032] In step (3), the adhesive can be an inorganic acid and / or an organic acid. The inorganic acid can be one or more of nitric acid, sulfuric acid, boric acid, and phosphoric acid, and the organic acid can be one or more of tartaric acid, citric acid, and oxalic acid.

[0033] In step (3), the mass fraction of the adhesive is 0.5% to 5.0% of the total mass of boehmite (calculated as alumina) and modified activated carbon B.

[0034] In step (3), the forming method can be at least one of extrusion, sheeting, and ball rolling. The formed shape can be clover-shaped, four-leaf clover-shaped, butterfly-shaped, cylindrical, spherical, or strip-shaped, etc.

[0035] In step (3), molding aids, such as at least one of extrusion aids and deionized water, can be added during the molding process according to molding requirements. The extrusion aid can be one or more of methylcellulose, ethylcellulose, guar gum, and starch. The mass of the extrusion aid added is 0.5% to 8.0% of the total mass of boehmite (calculated as alumina) and modified activated carbon B. The amount of deionized water used can be 80% to 120% of the total mass of boehmite (calculated as alumina) and modified activated carbon B.

[0036] In step (3), the drying temperature is 120-200℃ and the drying time is 2-12h.

[0037] In step (3), the calcination process employs programmed temperature increase at a rate of 1℃ / min to 3℃ / min. The calcination temperature is 550℃ to 750℃, the calcination time is 2 to 8 hours, and the calcination atmosphere is one or more of air, nitrogen, or water vapor, preferably air.

[0038] In step (4), the carbon coating treatment preferably uses an aqueous emulsion containing a polymer compound and water-soluble cellulose. In the aqueous emulsion, the polymer compound has a mass content of 8.0%–16.0%, and the water-soluble cellulose has a mass content of 0.5%–3.5%.

[0039] In step (4), the polymer compound is one or more of polyimide, polyfurfuryl alcohol, phenolic resin, etc.

[0040] In step (4), the water-soluble cellulose is one or more of hydroxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, etc.

[0041] In step (4), the ratio of the amount of water emulsion (in mL) to the amount of carrier C (in g) is 0.8 to 1.5 mL / g.

[0042] In step (4), the drying conditions are: a drying temperature of 120–200°C and a drying time of 2.0–12.0 h. The calcination conditions are: a calcination temperature of 500–700°C and a calcination time of 2.0–8.0 h, and an inert atmosphere, wherein the inert atmosphere is one or more of nitrogen and argon.

[0043] In step (5), the second active metal impregnation solution is an impregnation solution containing Mo and at least one selected from Group VIII metals (preferably Ni), wherein the molybdenum is derived from one or two of molybdenum oxide and ammonium heptamolybdate, and the nickel is derived from one or two of basic nickel carbonate and nickel nitrate. The content of MoO3 and Group VIII metals in the second active metal impregnation solution, calculated as oxides, is 10.0–50.0 g / 100 mL and 2.0–20.0 g / 100 mL, respectively. The mass of Group VIII metals introduced into the catalyst by the second active metal impregnation solution, calculated as oxides, accounts for 40.0%–70.0% of the total Group VIII metal oxide loading in the catalyst.

[0044] In step (5), at least one additive containing fluorine, phosphorus, silicon, or boron may be introduced into the second impregnation solution, preferably phosphorus. The amount of the additive added in the second impregnation solution, calculated as oxide, is 2.0 to 20.0 g / 100 ml, preferably 5.0 to 15.0 g / 100 ml.

[0045] In step (5), preferably, the second impregnation solution also contains a water-soluble polymer J. The water-soluble polymer J is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylamide, and methylcellulose. The content of water-soluble polymer J in the second active metal impregnation solution is 0.5–3.5 g / 100 mL.

[0046] In step (5), the impregnation method is saturated impregnation.

[0047] In step (5), the settling time is 24 to 48 hours.

[0048] In step (6), the drying temperature is 120-200℃ and the drying time is 2-12h.

[0049] In step (6), the roasting process employs a two-stage roasting method. The first stage roasting temperature is 350–450℃, the roasting time is 2–6 hours, and the roasting atmosphere is one or more of air, nitrogen, or water vapor, preferably air. The second stage roasting temperature is 450–750℃, the roasting time is 2–8 hours, and the roasting atmosphere is one or more of air, nitrogen, or water vapor, preferably nitrogen. The second stage roasting temperature is 150–250℃ higher than the first stage roasting temperature.

[0050] The third aspect of this invention provides the application of the above-mentioned catalyst in the hydrotreating of heavy oil and residual oil.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The residue hydrotreating demetallization catalyst is a bifunctional catalyst. During the reaction, hydrogenation and cracking reactions occur on the catalyst surface. Generally, when the acidity of the catalyst surface is too strong, the hydrogenated products will continue to crack on the catalyst surface, leading to condensation and coking, which affects the catalyst activity. Therefore, the acidity of the catalyst surface plays an important role in the distribution of residue hydrotreating products and the long-term operation of the unit. Through extensive research, the inventors discovered that firstly, impregnating the activated carbon surface with active metal Ni in the form of metal ions, and then molding it with boehmite, can effectively reduce the interaction between the metal and the alumina support, while simultaneously reducing the acidity of the catalyst surface and lowering the overall cracking performance of the catalyst. Secondly, a second active metal, Mo, is further introduced into the catalyst through saturated impregnation. The second impregnation of the active metal allows the catalyst to still possess strong hydrogenation performance. The purpose of the first impregnation is to effectively control the acidity of the catalyst surface by controlling the Ni content in the catalyst, while the purpose of the second impregnation is to further regulate the hydrogenation activity of the catalyst surface. This invention introduces active metal in two stages, which not only regulates the acidity of the catalyst surface but also further controls the hydrogenation activity of the catalyst; effectively regulates the active sites on the catalyst surface; and while improving the overall performance of the catalyst, it is beneficial to extend the operating cycle of the device.

[0053] Conventional active metal loading involves a single impregnation, resulting in the active metal mostly distributed on the catalyst surface. This leads to intense surface reactions and makes it difficult for large molecular reactants to penetrate the interior of the demetallization catalyst, limiting the utilization rate of the active metal. Furthermore, during sulfidation, the aggregated active metal results in insufficient sulfidation of the main metal, limiting its hydrogenation capacity. This invention introduces active metal through a two-stage impregnation process. To further reduce the interaction between the auxiliary metal nickel and the dried powder during grinding and kneading, firstly, the auxiliary metal nickel is impregnated onto activated carbon. A dispersing agent is introduced during this process to prevent metal aggregation on the nickel-containing activated carbon during calcination, ensuring uniform metal distribution on the activated carbon. Secondly, during grinding, an alkaline agent introduced onto the activated carbon forms a "protective film" during kneading, reducing the interaction between nickel and alumina. Finally, a carbon film is applied to the support containing the auxiliary metal. This carbon film ensures that the main metal molybdenum does not come into contact with the auxiliary metal nickel or the support during subsequent impregnation, allowing the main metal molybdenum to be uniformly dispersed on the carbon film. Finally, under a mixed atmosphere calcination, air removes the carbon film, and the main metal, molybdenum, is uniformly dispersed on the support. This method not only further weakens the interaction between the metal and the support but also effectively avoids the problem of uneven distribution of active metals caused by competitive adsorption on the support surface during mixed impregnation of the two metals. Furthermore, carbon coating is applied to support C, followed by calcination under an inert gas. Moisture gradually evaporates, and the latex particles are gradually compressed to form a thin film containing crosslinkable groups, forming a three-dimensional network film. This film temporarily provides loading sites for the second active metal. After catalyst calcination, this film disappears, and the second active metal is uniformly dispersed on the support, cooperating with the first active metal, which is beneficial for improving the activity and stability of hydrogenation demetallization. During catalyst calcination in a mixed atmosphere, air removes the carbon layer, allowing for uniform loading of the main active metal, while water vapor ensures further unobstructed pores in the catalyst.

[0054] In summary, the method of the present invention, through the comprehensive coordination of each step, significantly improves the activity and stability of the final residue oil hydrodemetallization catalyst. Detailed Implementation

[0055] The technical solutions 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.

[0056] In this invention, the pore structure and specific surface area of ​​the catalyst are characterized using the Mack ASAP-2420 physical adsorption instrument.

[0057] Example 1

[0058] (1) 54.09 g of the first active metal nickel (nickel nitrate), 42.0 g of dispersant (silica sol with a silica content of 30%) and 376.0 g of water were prepared into an impregnation solution, and 297.0 g of high-temperature activated carbon was saturated and impregnated. In the first active metal impregnation solution, the mass content of nickel as oxide was 3.60%, and the mass content of dispersant as silica was 3.72%. After impregnation, the carbon was dried at 120 °C for 6 h and calcined at 550 °C for 3 h to obtain modified activated carbon A.

[0059] (2) The modified activated carbon A obtained above was mixed with 3.5g of alkaline additive (NaOH), ground (the particle size after grinding is 5.0μm), and dried at 140℃ for 5h to obtain modified activated carbon B;

[0060] (3) 364.6g of pseudoboehmite (alumina content of 72.0%), 37.5g of modified activated carbon B, 5.47g of nitric acid, 8.0g of guar gum powder, and 360.0g of deionized water were mixed and kneaded, then extruded into a four-leaf clover shape, and then dried at 150℃ for 5h and calcined at 700℃ for 4h to obtain carrier C;

[0061] (4) Carbon coating treatment was applied to the surface of carrier C using an aqueous emulsion containing polyimide and hydroxymethyl cellulose. The mass content of polyimide in the aqueous emulsion was 9.0%, and the mass content of hydroxymethyl cellulose was 1.5%. The ratio of the volume of the aqueous emulsion (mL) to that of carrier C (g) was 1.5 mL / g. After drying at 180℃ for 6 h, the calcination conditions were: calcination at 650℃ for 5 h under a nitrogen atmosphere. After calcination, a three-dimensional network structure film was formed on the surface of carrier C, resulting in carrier D.

[0062] (5) The second active metal impregnation solution was impregnated onto the support D by saturation impregnation. The second active metal impregnation solution contained 16.86 g / 100 mL of MoO3, 3.42 g / 100 mL of NiO, 8.11 g / 100 mL of phosphoric acid, and 0.50 g / 100 mL of polyacrylamide. After standing for 24 h, the catalyst precursor was obtained.

[0063] (6) The catalyst precursor obtained in step (5) was dried at 120℃ for 6 hours. The calcination process employed a two-stage calcination method: the first stage calcination temperature was 400℃, the calcination time was 4 hours, and the calcination atmosphere was air; the second stage calcination temperature was 650℃, the calcination time was 6 hours, and the calcination atmosphere was nitrogen. The final hydrogenation demetallization catalyst CAT-1 was obtained. The physicochemical properties and composition of the catalyst are shown in Table 1.

[0064] Example 2

[0065] Compared with Example 1, the difference is that in step (1), 36.06 g of the first active metal nickel (nickel nitrate), dispersant (27.9 g of silica sol, with a silica content of 30%), and water were prepared into an impregnation solution, which was then used to saturate impregnate 297.0 g of high-temperature activated carbon. In the first active metal impregnation solution, the mass content of nickel as oxide was 2.40%, and the mass content of the dispersant as silica was 2.47%. In step (5), the second active metal impregnation solution contained 16.71 g / 100 mL of MoO3, 4.71 g / 100 mL of NiO, 8.01 g / 100 mL of phosphoric acid, and 0.50 g / 100 mL of polyacrylamide, and was used to saturate impregnate the support D. Finally, the hydrogenation demetallization catalyst CAT-2 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0066] Example 3

[0067] Compared with Example 1, the difference is that in step (4), the support C is subjected to surface carbon coating treatment using an aqueous emulsion containing polyimide and hydroxymethyl cellulose. The mass content of polyimide in the aqueous emulsion is 12.0%, and the mass content of hydroxymethyl cellulose is 2.5%. The ratio of the aqueous emulsion (by volume mL) to the support C (by mass g) is 1.2 mL / g. The calcination conditions are: calcination at 550°C for 6 hours under a nitrogen atmosphere. After calcination, a three-dimensional network structure film can be formed on the surface of the support C, resulting in support D. Finally, the hydrogenation demetallization catalyst CAT-3 is obtained. Other physicochemical properties and composition of the catalyst are shown in Table 1.

[0068] Example 4

[0069] Compared with Example 1, the difference is that in step (3), 370.4 g of boehmite (alumina mass content of 72.0%), 33.3 g of modified activated carbon B, 6.25 g of nitric acid, 6.0 g of guar gum powder, and 340.0 g of deionized water were mixed and kneaded, then extruded into a four-leaf clover shape, dried at 120°C for 8 h, and calcined at 650°C for 6 h to obtain support C. Finally, the hydrodemetallization catalyst CAT-4 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0070] Comparative Example 1

[0071] Compared with Example 1, the difference is that the calcination process in step (6) does not use stepwise calcination, the calcination temperature is 500℃, the calcination time is 3h, and the calcination atmosphere is air. Finally, the hydrogenation demetallization catalyst DAT-1 was obtained, and other physicochemical properties and composition of the catalyst are shown in Table 2.

[0072] Comparative Example 2

[0073] Compared with Example 1, the difference lies in that the amount of the first active metal nickel (nickel nitrate) in step (1) is changed to 69.78g, and an impregnation solution is prepared to saturate 297.0g of high-temperature activated carbon. In the first active metal impregnation solution, the mass content of nickel as oxide is 4.64%, and the mass content of the dispersant as silica is 3.72%. The second active metal impregnation solution in step (5) does not contain nickel. Finally, the hydrodemetallization catalyst DAT-2 is obtained. The physicochemical properties and composition of the catalyst are shown in Table 2.

[0074] Comparative Example 3

[0075] Compared with Example 1, the difference is that the first active metal nickel is not added in step (1), and the support D is impregnated with the second active metal impregnation solution by saturation impregnation in step (5). The second active metal impregnation solution contains 16.69 g / 100 mL of MoO3, 7.40 g / 100 mL of NiO, and 8.11 g / 100 mL of phosphoric acid. The amount of MoO3 introduced into the catalyst by the second active metal impregnation solution is 100% of the total MoO3 loading in the catalyst; the amount of NiO introduced into the catalyst by the second active metal impregnation solution is 100.0% of the total NiO loading in the catalyst. Finally, the hydrodemetallization catalyst DAT-3 is obtained. Other physicochemical properties and composition of the catalyst are shown in Table 2.

[0076] Comparative Example 4

[0077] Compared with Example 1, the difference is that no dispersant is added in step (1). No alkaline additive is added in step (2). The final hydrogenation demetallization catalyst DAT-4 is obtained. Other physicochemical properties and composition of the catalyst are shown in Table 2.

[0078] Comparative Example 5

[0079] Compared with Example 1, the difference is that the solution used in the carbon coating process in step (4) is changed to a glucose aqueous solution with a mass percentage of 10.5%, and the ratio of glucose aqueous solution (by volume mL) to the pre-support (by mass g) is 1.5 mL / g. Finally, the hydrodemetallization catalyst DAT-5 was prepared, and other physicochemical properties and composition of the catalyst are shown in Table 2.

[0080] Comparative Example 6

[0081] Compared with Example 1, the difference is that step (4) is omitted, i.e., the surface carbonization treatment is not performed. Finally, the hydrodemetallization catalyst DAT-6 was obtained, and other physicochemical properties and composition of the catalyst are shown in Table 2.

[0082] Table 1. Physicochemical properties and catalyst composition of the hydrodemetallization catalysts obtained in each example.

[0083]

[0084]

[0085] Table 2. Physicochemical properties and catalyst composition of the hydrodemetallization catalysts obtained in each comparative example.

[0086] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Catalyst number DAT-1 DAT-2 DAT-3 DAT-4 DAT-5 DAT-6 <![CDATA[Specific surface area, m 2 / g]]> 153 155 152 150 152 148 <![CDATA[Pore volume, cm 3 / g]]> 0.67 0.65 0.68 0.64 0.63 0.67 First active metal content NiO, wt% 3.47 6.50 0 3.44 3.45 3.42 Second active metal content <![CDATA[MoO3,wt%]]> 14.69 14.72 14.70 14.65 14.67 14.63 NiO, wt% 3.02 0 6.52 2.97 2.99 2.95 Additive content <![CDATA[P2O5,wt%]]> 3.07 3.08 3.08 3.05 3.06 3.03 Alumina: Activated Carbon (mass ratio) 7.0:1.0 7.0:1.0 7.0:1.0 7.0:1.0 7.0:1.0 7.0:1.0

[0087] Evaluation test

[0088] Activity stability tests were conducted on Examples 1-4 and Comparative Examples 1-6 using a 200mL fixed-bed hydrogenation test apparatus. The feedstock was residue oil with a density of 987.3 g / m³. 3 (20℃), S content 2.20wt%, Ni and V contents 31.7μg / g and 62.9μg / g respectively, CCR content 12.2wt%, the demetallization rate after 2000h of operation in Example 1 was 100%, and all others were relative demetallization rates. Specific experimental conditions are shown in Table 3, and experimental results are shown in Tables 4 and 5.

[0089] Table 3 Experimental conditions

[0090]

[0091]

[0092] Table 4. Test results of the hydrogenation demetallization catalysts in each example.

[0093]

[0094] Table 5. Experimental results of hydrogenation demetallization catalysts in each comparative example.

[0095]

[0096] As can be seen from Tables 1-5, the hydrodemetallization catalyst prepared according to the method of the present invention has a high specific surface area and pore volume, as well as high hydrogenation activity and stability, and can well meet the requirements of the hydrodemetallization process of residue oil.

Claims

1. A method for preparing a hydrodemetallization catalyst, the catalyst comprising a support and a second active metal, the support comprising alumina, activated carbon and a first active metal, wherein, The mass ratio of the alumina to the activated carbon is 4-12:1; the first active metal is at least one of Group VIII metals, and the second active metal comprises molybdenum and at least one selected from Group VIII metals; the content of the Group VIII metal in the first active metal, calculated as an oxide, is 30.0%-60.0% of the total Group VIII metal loading in the catalyst, calculated as an oxide, and the content of the Group VIII metal in the second active metal, calculated as an oxide, is 40.0%-70.0% of the total Group VIII metal loading in the catalyst, calculated as an oxide; and the preparation method of the catalyst comprises the following steps: (1) impregnating an activated carbon with a first active metal impregnation solution containing a dispersing aid, drying and calcining to obtain modified activated carbon A; (2) mixing the modified activated carbon A obtained in step (1) with an alkaline aid, grinding and drying to obtain modified activated carbon B; (3) mixing pseudoboehmite, the modified activated carbon B obtained in step (2) and a binder, shaping, drying and calcining to obtain carrier C; (4) performing surface carbon coating treatment on the carrier C, drying and calcining to obtain carrier D; (5) impregnating the carrier D obtained in step (4) with a second active metal impregnation solution, standing to obtain a catalyst precursor; (6) drying and calcining the catalyst precursor obtained in step (5) to obtain the hydrogen demetallization catalyst; In step (4), the carbon coating treatment uses an aqueous emulsion containing a high molecular compound and a water-soluble cellulose; In step (6), the calcining uses a two-stage calcining process, the first-stage calcining temperature is 350-450°C, and the calcining atmosphere is one or more of air, nitrogen or water vapor; the second-stage calcining temperature is 450-750°C, and the calcining atmosphere is one or more of air, nitrogen or water vapor.

2. The method of claim 1, wherein: In step (1), the dispersing aid is a silica sol; And / or, in step (2), the alkaline aid is selected from one or more of sodium hydroxide, potassium hydroxide and sodium carboxylate; And / or, in step (3), the binder is an inorganic acid and / or an organic acid, the inorganic acid is one or more of nitric acid, sulfuric acid, boric acid and phosphoric acid, and the organic acid is one or more of tartaric acid, citric acid and oxalic acid.

3. The method of claim 2, wherein: In the silica sol, the mass content of silicon dioxide is 20.0%-50.0%.

4. The method of claim 1, wherein: In the first active metal impregnation solution, the mass content of the first active metal oxide is 2.0%-15.0%; And / or, in the first active metal impregnation solution, the mass content of the dispersing aid, calculated as silicon dioxide, is 0.5%-5.0%.

5. The method of claim 1, wherein: In step (2), the mass ratio of the alkaline aid to the activated carbon used in step (1) is 0.01-0.10; And / or, in step (3), the mass of the binder is 0.5%-5.0% of the total mass of the pseudoboehmite, calculated as alumina, and the modified activated carbon B, Optionally, in step (3), an extrusion aid is added during the shaping process; the mass of the extrusion aid is 0.5%-8.0% of the total mass of the pseudoboehmite, calculated as alumina, and the modified activated carbon B.

6. The method of claim 5, wherein: In step (3), the extrusion aid is one or more of methyl cellulose, ethyl cellulose, sesbania powder, and starch.

7. The method of claim 1, wherein: In step (1), the calcination condition is that the temperature is 550-750°C, the time is 3-8h, and the calcination atmosphere is one or more of air, water vapor, and nitrogen. In step (3), the calcination condition is that the temperature is 550-750°C, the time is 2-8h, and the calcination atmosphere is one or more of air, nitrogen, and water vapor. In step (4), the calcination condition is that the temperature is 500-700°C, the time is 2.0-8.0h, and the calcination atmosphere is an inert atmosphere, which is one or more of nitrogen and argon.

8. The method of claim 7, wherein: In step (3), the calcination atmosphere is air.

9. The method of claim 1, wherein: In step (4), the high molecular compound is one or more of polyimide, polyfurfuryl alcohol, and phenol-formaldehyde resin; and the water-soluble cellulose is one or more of methylcellulose, hydroxyethylmethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, and hydroxyethyl cellulose.

10. The method of claim 1, wherein: In the water emulsion, the mass content of the high molecular compound is 8.0%-16.0%, and the mass content of the water-soluble cellulose is 0.5%-3.5%. In step (4), the high molecular compound is one or more of polyimide, polyfurfuryl alcohol, and phenol-formaldehyde resin; and the water-soluble cellulose is one or more of methylcellulose, hydroxyethylmethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, and hydroxyethyl cellulose.

11. The method of claim 1, wherein: In the water emulsion, the mass content of the high molecular compound is 8.0%-16.0%, and the mass content of the water-soluble cellulose is 0.5%-3.5%.

12. The method of claim 1, wherein: In step (4), the high molecular compound is one or more of polyimide, polyfurfuryl alcohol, and phenol-formaldehyde resin; and the water-soluble cellulose is one or more of methylcellulose, hydroxyethylmethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, and hydroxyethyl cellulose.

13. The method of claim 1, wherein: The second active metal impregnation solution further contains a water-soluble high polymer J, which is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylamide, and methyl cellulose.

14. The method of claim 11, wherein: In the second active metal impregnation solution, the contents of MoO3 and Group VIII metal in terms of oxides are 10.0-50.0g / 100mL and 2.0-20.0g / 100mL, respectively.

15. The method of claim 12, wherein: The content of the additive in terms of oxides in the second active metal impregnation solution is 2.0-20.0g / 100mL.

16. The method of claim 14, wherein: The content of the water-soluble high polymer J in the second active metal impregnation solution is 0.5-3.5g / 100mL.

17. The method of claim 1, wherein: The content of the additive in terms of oxides in the second active metal impregnation solution is 5.0-15.0g / 100mL.

18. The method of claim 17, wherein: In step (6), the first-stage calcination time is 2-6h, and the calcination atmosphere is air; and the second-stage calcination time is 2-8h, and the calcination atmosphere is nitrogen. The second-stage calcination temperature is 150-250°C higher than the first-stage calcination temperature.

20. The catalyst of claim 19, wherein:

19. The hydrogen demetallization catalyst prepared by the preparation method of any one of claims 1-18.

21. The catalyst of claim 19, wherein: The specific surface area of the catalyst is 140 to 210 m 2 / g, and the pore volume is 0.50 to 1.25 mL / g.

22. The catalyst of claim 21, wherein: The specific surface area of the catalyst is 150 to 180 m 2 / g, and the pore volume is 0.70 to 1.00 mL / g.

23. The catalyst of claim 19, wherein: In the catalyst, the content of MoO3 is 9.0%-35.0% and the content of Group VIII metal oxide is 5.0%-16.0% based on the mass of the catalyst. In the catalyst, the content of the additive component in terms of oxides is 2.0%-11.0% based on the mass of the catalyst.

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