Residue hydroprocessing catalyst and method for making same

Abstract

The present application provides a residue hydroprocessing catalyst and a preparation method thereof. The residue hydroprocessing catalyst has a core-shell structure comprising an inner layer and an outer layer. The inner layer is mesoporous alumina loaded with active metals, and the outer layer is macroporous alumina loaded with active metals. The active metals are at least one of Group 6B metals and / or Group 8 metals. The mesoporous alumina has a pore size of 5-20 nm, and the macroporous alumina has a pore size of 20-500 nm. The present application also provides a preparation method of the residue hydroprocessing catalyst and a residue hydroprocessing method. The catalyst has a greater capacity for depositing impurity metals and suitable hydrodesulfurization and hydrodecarbonization activities, and can realize efficient conversion of residue. The catalyst has the advantages of high activity and good selectivity.

Description

Technical Field

[0001] This invention belongs to the field of petrochemical catalysis technology, and in particular relates to a hydrogenation catalytic material for treating inferior heavy oil feedstocks such as residual oil and its preparation method. Background Technology

[0002] With the world's oil resources becoming increasingly scarce, and the trend towards heavier and lower-quality crude oil, the deep processing and upgrading technologies for low-quality heavy oil are attracting more and more attention. Among these technologies, catalytic cracking of residual oil is one of the most effective processes for lightening heavy oil. Residual oil contains high levels of sulfur and metallic impurities such as Ni and V, which typically require hydrotreating to remove these impurities before further processing, such as catalytic cracking, to produce clean gasoline, diesel, and other petroleum products and chemical feedstocks. The main reactions in this process include hydrodemetallization, hydrodesulfurization, hydronitrogenation, aromatics saturation, and hydrocarbon hydrocracking.

[0003] In recent years, with the advancements in fixed-bed residue hydrotreating and catalytic cracking technologies, the focus of fixed-bed residue hydrotreating technology has shifted to catalyst activity stability and long-term stable operation of the unit. Analysis of waste materials from industrial residue hydrotreating plants reveals that catalyst deactivation occurs from top to bottom, primarily due to metal deposition and carbon buildup. For heavy oil hydrotreating catalysts, unobstructed channels and large pore volumes are essential. Unobstructed channels facilitate the diffusion and reaction of large hydrocarbon molecules in heavy oil, enhancing the catalyst's impurity removal activity. Simultaneously, they prevent metal impurity deposition or reaction coking that could clog catalyst pores and lead to rapid deactivation, promoting the deposition of metal impurities into the catalyst channels and improving the catalyst's metal carrying capacity and activity stability.

[0004] Patent CN105567311A discloses a catalyst gradation method for residue oil hydrotreating and a residue oil hydrotreating method. The catalyst gradation method involves sequentially loading a hydroprotection catalyst, a hydrodemetallization catalyst, a hydrodesulfurization catalyst, and a hydrocarbon removal catalyst along the flow direction in a residue oil hydrotreating unit. The total acid content of each catalyst gradually increases along the flow direction, the proportion of Lewis acid gradually decreases, and the proportion of Bronsted acid gradually increases. The residue oil hydrotreating method involves injecting residue oil into a residue oil hydrotreating unit for hydrotreating, wherein the catalyst in the residue oil hydrotreating unit is loaded according to the above gradation method. In the residue oil hydrotreating process, the catalyst gradation method provided by this invention can significantly improve the carbon removal rate. However, it requires the combined use of multiple catalysts. Summary of the Invention

[0005] To address the problems existing in existing residue oil hydrotreating catalysts and their preparation methods, the core objective of this invention is to provide a residue oil hydrotreating catalyst and its preparation method. The catalyst has a greater ability to deposit impurity metals and suitable hydrotreating desulfurization and residual carbon removal activity, enabling efficient conversion of residue oil. The catalyst also has the advantages of high activity and good selectivity.

[0006] The first aspect of this invention provides a residue hydrotreating catalyst, wherein the residue hydrotreating catalyst has a core-shell structure comprising an inner layer and an outer layer, wherein the inner layer is mesoporous alumina loaded with an active metal, and the outer layer is macroporous alumina loaded with an active metal; the active metal is at least one of Group VIB metals and / or Group VIII metals; the pore size of the mesoporous alumina is 5–20 nm, preferably 8–15 nm; and the pore size of the macroporous alumina is 20–500 nm, preferably 30–200 nm.

[0007] Furthermore, according to a specific embodiment of the present invention, the weight ratio of macroporous alumina to mesoporous alumina is 0.5:1 to 20:1, preferably 1:1 to 10:1.

[0008] Furthermore, according to a specific embodiment of the present invention, the most probable pore size of the macroporous alumina is 25–350 nm, and the pore volume is 0.4–2.7 cm³. 3 / g.

[0009] Furthermore, according to a specific embodiment of the present invention, the most probable pore size of the mesoporous alumina is 6–18 nm, and the pore volume is 0.3–1.1 cm³. 3 / g.

[0010] Furthermore, according to a specific embodiment of the present invention, the Group VIB metal is preferably Mo and / or W, and the Group VIII metal is preferably Co and / or Ni. The active metal exists on the alumina in the form of an oxide.

[0011] Furthermore, according to a specific embodiment of the present invention, the active metal content can be flexibly adjusted according to actual needs. Specifically, in the present invention, based on the weight of the catalyst and calculated as oxides, the content of Group VIB metals is generally controlled to be 5 to 25 wt%, and the content of Group VIII metals is generally controlled to be 1 to 8 wt%.

[0012] A second aspect of this invention provides a method for preparing a residue hydrotreating catalyst, comprising the following steps: (1) Aluminum-containing inorganic salt, solution containing active metal compound and precipitant are mixed to form a gel reaction. After the reaction, the mixture is aged. Then the solid material after separation and washing is mixed with alcohol solution and separated to obtain wet filter cake. (2) Under mixed conditions, the precursor solution of alumina is mixed with the solution containing dispersant and subjected to hydrolysis or gelation reaction to obtain sol; (3) The wet filter cake obtained in (1) is mixed evenly with the sol obtained in step (2), and the reaction is carried out at 30℃~100℃. The gel obtained from the reaction is further subjected to supercritical drying to obtain the carrier precursor. (4) The catalyst is obtained by mixing the support precursor obtained in step (3) with the solution containing the active metal compound, drying and calcining.

[0013] Furthermore, according to a specific embodiment of the present invention, the aluminum-containing inorganic salt in step (1) may be selected from one or more of aluminum sulfate, aluminum nitrate, and aluminum chloride.

[0014] Furthermore, according to a specific embodiment of the present invention, the precipitant in step (1) is an inorganic alkaline compound, and more specifically, the precipitant is preferably selected from one or more of ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, and sodium aluminate. The amount of precipitant used is controlled according to the pH value.

[0015] Furthermore, according to a specific embodiment of the present invention, the gelation reaction conditions in step (1) are as follows: the gelation temperature is 30-80℃, the pH value is controlled at 7.5-10.0, and the gelation time is 0.5-4.0h.

[0016] Furthermore, according to a specific embodiment of the present invention, the aging temperature in step (1) is less than 100°C, preferably 30 to 80°C; the aging time is 0.5h to 5h.

[0017] Furthermore, according to a specific embodiment of the present invention, the separation in step (1) can be any one of centrifugal separation, vacuum filtration, filtration, etc.

[0018] Furthermore, according to a specific embodiment of the present invention, the washing in step (1) is water washing, preferably using deionized water. There is no special limitation on the number of washings, but generally it is 2 to 10 times of washing with water.

[0019] Furthermore, according to a specific embodiment of the present invention, the alcohol in step (1) can be selected from one or more of ethanol, glycerol, polyethylene glycol, and polyvinyl alcohol, preferably polyethylene glycol, with a molecular weight of 200 to 10,000. The mass concentration of the alcohol solution is 2 to 50 wt%, preferably 5 to 30 wt%. The amount of alcohol solution used is 2 to 10 times the weight of the wet filter cake.

[0020] Furthermore, according to a specific embodiment of the present invention, the specific process of the gelation reaction in step (1) is as follows: bottom water is added to the reactor, and then aluminum-containing inorganic salt, active metal compound solution, and precipitant are preferably introduced into the reactor in a co-current manner to carry out the gelation reaction.

[0021] Furthermore, according to a specific embodiment of the present invention, the active metal compound in steps (1) and (4) is a metal compound containing Group VIB and / or a compound containing Group VIII metals, wherein the metal compound containing Group VIB is an inorganic salt of Mo and / or W, and is one or more of ammonium molybdate, ammonium tungstate, molybdenum oxide, and tungsten oxide. The compound containing Group VIII metal is an inorganic salt of metallic Ni and / or Co, and can be one or more of nickel nitrate, basic nickel carbonate, nickel citrate, cobalt nitrate, basic cobalt carbonate, and cobalt citrate.

[0022] Furthermore, according to a specific embodiment of the present invention, the precursor of alumina in step (2) can be an organic aluminum-containing compound and / or an inorganic aluminum-containing compound, wherein the organic aluminum-containing compound is one or more of alkyl aluminum and alkoxy aluminum, the alkyl aluminum is at least one of trimethyl aluminum, triethyl aluminum, tripropyl aluminum, and triisobutyl aluminum, the alkoxy aluminum has 3 to 20 carbons, and can be specifically selected from at least one of triethanolamine aluminum, tripropoxide aluminum, triisopropoxide aluminum, and tri-n-butoxy aluminum, and the inorganic aluminum-containing compound is one or more of aluminum sulfate, aluminum nitrate, aluminum chloride, and sodium aluminate.

[0023] Furthermore, according to a specific embodiment of the present invention, the dispersant in step (2) is an alcohol ether compound, and the specific dispersant can be one or more of ethylene glycol monomethyl ether, ethylene glycol phenyl ether, ethylene glycol isopropyl ether, propylene glycol methyl ether, tripropylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol butyl ether, etc.

[0024] Furthermore, according to a specific embodiment of the present invention, the amount of dispersant used in step (2) is 0.5 to 30% of the weight of the alumina precursor (calculated as alumina).

[0025] Furthermore, according to a specific embodiment of the present invention, the hydrolysis reaction conditions in step (2) are as follows: the hydrolysis temperature is 40-90℃, the pH value is controlled at 4.0-8.5, and the hydrolysis time is 0.5-5h. The pH value is adjusted by adding an acidic or alkaline substance. The acidic substance used can be an inorganic acid or an organic acid, such as one or more of nitric acid, sulfuric acid, hydrochloric acid, acetic acid, formic acid, and carbonic acid. The alkaline substance used is selected from one or more of sodium hydroxide, potassium hydroxide, ammonia, and sodium aluminate.

[0026] Furthermore, according to a specific embodiment of the present invention, the supercritical drying in step (3) uses carbon dioxide as the drying medium, with a pressure of 1 to 15 MPa, a drying temperature of 20 to 100°C, and a drying medium flow rate of 40 liters / hour to 500 liters / hour.

[0027] Furthermore, according to a specific embodiment of the present invention, the drying conditions in step (4) are as follows: the drying temperature is 50-180°C, preferably 80-150°C, and the drying time is 1-24h, preferably 3-12h.

[0028] Furthermore, according to a specific embodiment of the present invention, the calcination conditions in step (4) are as follows: the calcination temperature is 400℃~800℃, preferably 450℃~650℃; the calcination time is 1~12h, preferably 3~8h. The calcination is not particularly restricted by the atmosphere, and can be carried out under a nitrogen or air atmosphere.

[0029] Furthermore, according to a specific embodiment of the present invention, in step (4), while mixing the carrier precursor obtained in step (3) and the solution containing the active metal compound, a peptizing agent and an extrusion aid are added. The extrusion aid and peptizing agent are well known to those skilled in the art, and the specific types and amounts of substances used can be determined according to existing knowledge in the art. Specifically, in the present invention, the peptizing agent is one or more of nitric acid, oxalic acid, and phosphoric acid, and its amount is 1.0wt% to 10.0wt% of the catalyst weight; the extrusion aid can be one or more of guar gum powder, starch, methylcellulose, and polyvinyl alcohol, and its amount is 1.0wt% to 5.0wt% of the catalyst weight.

[0030] A third aspect of the present invention provides a method for treating residual oil with hydrogenation, wherein the residual oil is reacted with hydrogen in the presence of the above-mentioned residual oil hydrogenation catalyst or the residual oil hydrogenation catalyst prepared by the above-mentioned method.

[0031] Furthermore, according to a specific embodiment of the present invention, the reaction conditions are a hydrogen partial pressure of 10–22 MPa, a reaction temperature of 300°C–450°C, and a volume hourly space velocity of 0.1–4.5 hr. -1 The volume ratio of hydrogen to residual oil is 500–2000. The residual oil and hydrogen enter the unit from the feed port of the residual oil hydrogenation unit to react. The reaction product exits the unit and enters the fractionation tower, where it is separated to obtain the target product.

[0032] Compared with existing residue hydrotreating catalysts and their preparation methods, the residue hydrotreating catalyst, its preparation method, and its application provided by this invention have the following advantages: 1. The residue hydrotreating catalyst provided by this invention has a core-shell structure, wherein the core is mesoporous alumina loaded with a relatively large amount of active metal, and the outer layer is macroporous alumina loaded with a relatively small amount of active metal. When the residue feedstock comes into contact with the catalyst, it first enters the outer layer with large pores and high porosity. This facilitates the entry of large molecules and the removal of metals at the active sites in the outer layer. Furthermore, the large pores can accommodate a large amount of metal impurities. The material reacting in the outer layer then further enters the active sites of the mesoporous alumina in the core for hydrotreating, desulfurization, and decarbonization reactions, ultimately producing the target product. The provided residue hydrotreating catalyst not only has strong demetallization and metal-containing capabilities but also possesses active sites for hydrotreating, desulfurization, and decarbonization. Multiple functions such as demetallization, desulfurization, and decarbonization can be achieved simultaneously on a single catalyst. This solves the problem that, due to the presence of a large amount of metal impurities and fused-ring compounds in residue oil, metals and macromolecular compounds easily adsorb onto the surface of the active sites and clog the pores during the hydrotreating process.

[0033] 2. In the method for preparing the residue hydrogenation catalyst provided by this invention, the dispersant in the sol is adsorbed onto the surface of the mesoporous alumina particles, making the mesoporous alumina uniformly dispersed in the sol and gel, and less prone to aggregation. Furthermore, during drying, the network structure of the macroporous alumina composite aerogel is ensured not to collapse, while mesoporous alumina is interspersed within it. The liquid filling the mesoporous alumina pores also prevents sol molecules from entering the mesoporous alumina pores. After calcination, the pores of the mesoporous alumina are restored, which is beneficial for the entry and exit of reactants. Detailed Implementation

[0034] The technical features of the present invention are further described below through embodiments, but these embodiments are not intended to limit the present invention.

[0035] In this paper, the pore size was measured using the cryogenic liquid nitrogen physical adsorption method, and the instrument used was the ASAP2405 and 2420 physical adsorption instrument manufactured by the American company.

[0036] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0037] In this paper, the method for preparing the molybdenum-nickel-phosphorus solution is to mix molybdenum-containing and nickel-containing compounds with deionized water according to the specified ratio, heat to boiling, add phosphorus-containing compounds dropwise, and allow the solution to gradually become clear until a transparent solution is formed, thus obtaining the molybdenum-nickel-phosphorus solution.

[0038] Example 1 Take 1 mol / L aluminum nitrate, molybdenum-nickel-phosphorus solution (containing 8 g nickel oxide / 100 mL and 40 g molybdenum oxide / 100 mL), and 1 mol / L ammonia water and drip them dropwise into a container with bottom water. Maintain the temperature at 50℃ and pH at 8.5, stir and age for 1 hour, filter, wash three times with deionized water, drain, and mix with an aqueous solution containing polyvinyl alcohol (molecular weight 5500, containing 5 wt% polyvinyl alcohol) at a weight ratio of 1:5. Stir for 10 minutes and filter to obtain a wet filter cake. Mix aluminum nitrate and ethylene glycol methyl ether at a weight ratio of 100:3, add ammonia water to adjust the pH to 7, and react at 65℃ to obtain a sol. Add the wet filter cake (mesoporous alumina) to the sol, so that the mesoporous alumina accounts for 20 wt% of the total alumina, stir evenly, and then transfer to a constant temperature water bath at 65℃ and let stand for 3 hours to form a gel. The gel was subjected to supercritical drying in a carbon dioxide system at 3 MPa, 60 °C, and a flow rate of 100 L / h to obtain an aerogel.

[0039] Alumina aerogel, molybdenum-nickel-phosphorus solution (containing 10 g / 100 mL nickel oxide and 55 g / 100 mL molybdenum oxide), 1.2 g nitric acid, and 3 g guar gum powder were mixed, kneaded, and extruded into strips. The mixture was dried in a forced-air drying oven at 120°C for 5 hours and then calcined at 580°C for 3 hours to obtain the catalyst product. The composition and properties of the catalyst are shown in Table 1.

[0040] Example 2 Take 2 mol / L aluminum sulfate, ammonium molybdate solution (containing 30 g / 100 mL molybdenum oxide), nickel nitrate (containing 15 g / 100 mL nickel oxide), and 3 mol / L ammonium carbonate and add them dropwise in a container with bottom water. Maintain the temperature at 45℃ and pH at 9.0, stir and age for 2 hours, filter, wash three times with deionized water, drain, and mix with an aqueous solution containing polyethylene glycol (molecular weight 600) (containing 8 wt% polyethylene glycol) at a weight ratio of 1:6. Stir for 10 minutes, then filter to obtain a wet filter cake. Mix aluminum nitrate and propylene glycol butyl ether at a weight ratio of 100:6, add ammonia to adjust the pH to 7.5, and react at 50℃ to obtain a sol. Add the treated mesoporous alumina (wet filter cake) to the sol, making the mesoporous alumina account for 15 wt% of the total alumina. Stir evenly, then transfer to a constant temperature water bath at 50℃ and let stand for 3.5 hours to form a gel. The gel was subjected to supercritical drying in a carbon dioxide system at 4.5 MPa, 50 °C, and a flow rate of 180 L / h to obtain an aerogel.

[0041] Alumina aerogel, molybdenum-nickel-phosphorus solution (containing 8 g / 100 mL nickel oxide and 45 g / 100 mL molybdenum oxide), 2 g nitric acid, and 4 g guar gum powder were mixed, kneaded, and extruded into strips. The mixture was dried in a forced-air drying oven at 170°C for 5 hours and then calcined at 650°C for 3 hours to obtain the catalyst product. The composition and properties of the catalyst are shown in Table 1.

[0042] Example 3 Take 1.5 mol / L aluminum sulfate, ammonium molybdate solution (containing 45 g / 100 mL of molybdenum oxide), nickel nitrate (containing 12 g / 100 mL of nickel oxide), and 2 mol / L sodium aluminate and drip them dropwise into a container with bottom water. Maintain the temperature at 45℃ and pH at 8.5, stir and age for 1.5 h, filter, wash three times with deionized water, drain, and mix with an aqueous solution containing polyethylene glycol (molecular weight 1000) (containing 6% polyethylene glycol) at a weight ratio of 1:4. Stir for 10 minutes, then filter to obtain a wet filter cake. Mix aluminum isopropoxide and ethanol at a ratio of 10:1, add 6% propylene glycol methyl ether and mix well. Hydrolyze slowly at 80℃, with an aluminum isopropoxide:water ratio of 1:10. Add the wet filter cake to the sol so that the mesoporous alumina accounts for 25% of the total alumina. Stir well, then transfer to a constant temperature water bath at 60℃ and let stand for 3 hours to form a macroporous alumina gel. The gel was subjected to supercritical drying in a carbon dioxide system to obtain an aerogel composite. The drying conditions were the same as in Example 1.

[0043] Alumina aerogel was mixed with nickel nitrate solution (containing 12 g / 100 mL of nickel oxide), ammonium molybdate solution (containing 25 g / 100 mL of molybdenum oxide), 3 g of nitric acid, and 3 g of guar gum powder. The mixture was kneaded and extruded into strips, dried in a forced-air drying oven at 180°C for 4 hours, and calcined at 500°C for 5 hours to obtain the catalyst product. The composition and properties of the catalyst are shown in Table 1.

[0044] Example 4 Take 1.0 mol / L aluminum chloride solution, ammonium molybdate solution (containing 15 g / 100 mL molybdenum oxide), nickel nitrate solution (containing 12 g / 100 mL nickel oxide), ammonium metatungstate solution (containing 20 wt% tungsten oxide), and 1 mol / L ammonia water and drip them dropwise into a container with bottom water. Maintain the temperature at 55℃ and pH at 8.0, stir and age for 2.5 h, filter, wash 4 times with deionized water, drain and mix with an aqueous solution of polyethylene glycol (molecular weight 2000) (containing 7.0 wt% polyethylene glycol) at a weight ratio of 1:7. Stir for 30 minutes and filter to obtain a wet filter cake. Aluminum isopropoxide and ethanol were mixed in a weight ratio of 12:1, and 6 wt% propylene glycol phenyl ether was added and mixed thoroughly. The ratio of aluminum isopropoxide to water was 1:15 (by weight). The wet filter cake was added to the sol and slowly hydrolyzed at 75°C. The wet filter cake was then added to the sol again, ensuring that the mesoporous alumina accounted for 30 wt% of the total alumina content. The mixture was stirred thoroughly and then transferred to a constant temperature water bath at 50°C and allowed to stand for 3 hours to form a gel. The gel was then subjected to supercritical drying under a carbon dioxide system to obtain alumina aerogel. The drying conditions were the same as in Example 1.

[0045] Alumina aerogel and an active metal solution (10 g / 100 mL tungsten oxide, 8 g / 100 mL molybdenum oxide, 2.5 g / 100 mL cobalt oxide), 1 g nitric acid, and 3 g guar gum powder were mixed, kneaded, and extruded into strips. The mixture was dried in a forced-air drying oven at 160 °C for 4 hours and then calcined at 550 °C for 3 hours to obtain the catalyst product. The composition and properties of the catalyst are shown in Table 1.

[0046] Comparative Example 1 2 mol / L aluminum sulfate, ammonium molybdate solution (containing 30 g / 100 mL molybdenum oxide), nickel nitrate (containing 15 g / 100 mL nickel oxide), and 3 mol / L ammonium carbonate were added dropwise to a container with a bottom water. The temperature was maintained at 45℃ and the pH at 9.0. The mixture was stirred and aged for 2 hours, then filtered. The filter cake was washed three times with deionized water and filtered again to obtain a wet filter cake. Aluminum nitrate and ammonia were mixed, and the pH was adjusted to 7.5. The mixture was reacted at 50℃ to obtain a sol. The treated mesoporous alumina (wet filter cake) was added to the sol, making the mesoporous alumina account for 15 wt% of the total alumina. The mixture was stirred evenly and then transferred to a constant temperature water bath at 50℃ and allowed to stand for 3.5 hours to form a gel. The gel was then subjected to supercritical drying in a carbon dioxide system at 4.5 MPa, 50℃, and a flow rate of 180 L / h to obtain alumina aerogel.

[0047] Alumina aerogel, ammonium molybdate solution (molybdenum oxide concentration 35g / 100mL), nickel nitrate solution (containing nickel oxide 16g / 100mL), 2g guar gum powder, and 1.5g dilute nitric acid were mixed, kneaded, and extruded into strips. The mixture was dried in a forced-air drying oven at 170℃ for 3 hours and then calcined at 500℃ for 3 hours to obtain the final catalyst. The composition and properties of the catalyst are shown in Table 1.

[0048] Comparative Example 2 Aluminum nitrate and ethylene glycol methyl ether were mixed in a ratio of 100:3 (by weight), and ammonia was added to adjust the pH to 7. The mixture was reacted at 65°C to obtain a sol, which was then transferred to a constant temperature water bath at 65°C and allowed to stand for 3 hours to form a macroporous alumina gel. The gel was then subjected to supercritical drying in a carbon dioxide system at 3 MPa, 60°C, and a flow rate of 100 L / h to obtain an aerogel composite. The wet filter cake obtained in Example 1 was dried at 120°C for 5 hours, pulverized, and set aside for later use.

[0049] Aerogel, mesoporous alumina, and a molybdenum-nickel-phosphorus solution (containing 10 g / 100 mL nickel oxide and 55 g / 100 mL molybdenum oxide), 1.2 g nitric acid, and 3 g guar gum powder were mixed, kneaded, and extruded into strips. The mixture was then dried in a forced-air drying oven at 120 °C for 5 hours and calcined at 580 °C for 3 hours to obtain the catalyst product. The composition and properties of the catalyst are shown in Table 1.

[0050] Evaluation Test The specific process for evaluating the activity and stability of the catalysts prepared in Examples 1, 2, 3, 4, and Comparative Examples 1 and 2 is as follows: The evaluation was conducted on a 200 mL fixed-bed residue hydrotreating unit. During the catalyst sulfidation process, the sulfiding oil was a mixture of jet fuel and carbon disulfide with a sulfur content of 20,000 μg / g. 100 mL of oxidizing catalyst was loaded into the hydrotreating reactor, hydrogen was introduced, and the pressure was maintained at 15 MPa. The temperature was increased to 150°C at a rate of 20°C / h, and the sulfiding oil was introduced. The temperature was held for 3 hours, then increased to 230°C at a rate of 20°C / h and held for 8 hours. The temperature was then increased to 320°C and held for 8 hours to complete the sulfidation. Then, feedstock oil was introduced, the temperature was increased to 420°C, and the temperature was held for 8 hours before sampling and analysis. The feedstock used for evaluation was atmospheric residue oil with a sulfur content of 6.7%, a carbon residue of 18.4%, a Ni content of 109 µg / g, a V content of 151 µg / g, an Fe content of 79 µg / g, and a Ca content of 54 µg / g. The specific reaction conditions were: reaction pressure 15 MPa, liquid hourly space velocity (LHSV) 1.0 h⁻¹. -1 The reaction temperature was 420℃, the hydrogen-to-oil volume ratio was 1000:1, and the evaluation results are shown in Table 2.

[0051] Table 1. Physicochemical properties and evaluation results of the catalysts Note: Active metal content on macroporous alumina = total metal content of catalyst - active metal content on mesoporous alumina * percentage of mesoporous alumina in total alumina; metal content in comparative examples refers to the total metal content of catalyst.

[0052] Table 2 Evaluation Results of Residue Oil As shown in Tables 1 and 2, the residue oil hydrogenation catalyst prepared by this technology has a large pore size, which is conducive to the adsorption and reaction of macromolecules and beneficial to the removal of metal impurities in residue oil. The active centers on the mesoporous alumina have good desulfurization and residual carbon removal activities.

Claims

1. A residue hydrotreating catalyst, wherein the residue hydrotreating catalyst has a core-shell structure comprising an inner layer and an outer layer, wherein the inner layer is mesoporous alumina loaded with a relatively large amount of active metal, and the outer layer is macroporous alumina loaded with a relatively small amount of active metal; the active metal is a Group VIB metal and / or a Group VIII metal; the pore size of the mesoporous alumina is 5-15 nm, and the pore size of the macroporous alumina is 20-500 nm; the preparation method of the residue hydrotreating catalyst includes the following steps: (1) Aluminum-containing inorganic salt, solution containing active metal compound and precipitant are mixed to form a gel reaction. After the reaction, the mixture is aged. Then, the solid material after separation and washing is mixed with alcohol solution and separated to obtain wet filter cake. (2) Under mixed conditions, the precursor solution of alumina is mixed with the solution containing the dispersant and hydrolyzed to obtain a sol; the dispersant is an alcohol ether compound; (3) The wet filter cake obtained in (1) is mixed evenly with the sol obtained in step (2), and the reaction is carried out at 30℃~100℃. The gel obtained from the reaction is further subjected to supercritical drying to obtain the carrier precursor. (4) The support precursor obtained in step (3) and the solution containing the active metal compound are mixed, dried and calcined to obtain the catalyst; the active metal compound in steps (1) and (4) is a metal compound containing Group VIB and / or a compound containing Group VIII metal.

2. The residue hydrotreating catalyst according to claim 1, characterized in that: The mesoporous alumina has a pore size of 8–15 nm, and the macroporous alumina has a pore size of 30–200 nm.

3. The residue hydrotreating catalyst according to claim 1, characterized in that: The weight ratio of macroporous alumina to mesoporous alumina is 0.5:1 to 20:

1.

4. The residue hydrotreating catalyst according to claim 1, characterized in that: The weight ratio of macroporous alumina to mesoporous alumina is 1:1 to 10:

1.

5. The residue hydrotreating catalyst according to claim 1, characterized in that: The most probable pore size of the macroporous alumina is 25–350 nm, and the pore volume is 0.4–2.7 cm³. 3 / g.

6. The residue hydrotreating catalyst according to claim 1, characterized in that: The most probable pore size of the mesoporous alumina is 6–14 nm, and the pore volume is 0.3–1.1 cm³. 3 / g.

7. A method for preparing the residue hydrotreating catalyst according to any one of claims 1-6, comprising the following steps: (1) Aluminum-containing inorganic salt, solution containing active metal compound and precipitant are mixed to form a gel reaction. After the reaction, the mixture is aged. Then, the solid material after separation and washing is mixed with alcohol solution and separated to obtain wet filter cake. (2) Under mixed conditions, the precursor solution of alumina is mixed with the solution containing the dispersant and hydrolyzed to obtain a sol; the dispersant is an alcohol ether compound; (3) The wet filter cake obtained in (1) is mixed evenly with the sol obtained in step (2), and the reaction is carried out at 30℃~100℃. The gel obtained from the reaction is further subjected to supercritical drying to obtain the carrier precursor. (4) The support precursor obtained in step (3) and the solution containing the active metal compound are mixed, dried and calcined to obtain the catalyst; the active metal compound in steps (1) and (4) is a metal compound containing Group VIB and / or a compound containing Group VIII metal.

8. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The aluminum-containing inorganic salt in step (1) is selected from one or more of aluminum sulfate, aluminum nitrate, and aluminum chloride.

9. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The precipitant in step (1) is an inorganic alkaline compound.

10. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The precipitant in step (1) is selected from one or more of ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, and sodium aluminate.

11. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The gelation reaction conditions in step (1) are as follows: gelation temperature is 30-80℃, pH value is controlled at 7.5-10.0, and gelation time is 0.5-4.0h.

12. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The aging temperature in step (1) is less than 100℃ and the aging time is 0.5h to 5h.

13. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The aging temperature in step (1) is 30 to 80°C and the aging time is 0.5 to 5 hours.

14. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The alcohol in step (1) is selected from one or more of ethanol, glycerol, polyethylene glycol, and polyvinyl alcohol.

15. The method for preparing the residue hydrotreating catalyst according to claim 14, characterized in that: The alcohol in step (1) is polyethylene glycol, and the molecular weight of polyethylene glycol is 200 to 10,000.

16. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The mass concentration of the alcohol solution in step (1) is 2 to 50 wt%, and the amount of alcohol solution used is 2 to 10 times the weight of the wet filter cake.

17. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The mass concentration of the alcohol solution in step (1) is 5-30 wt%; the amount of alcohol solution used is 2-10 times the weight of the wet filter cake.

18. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The metal compounds containing Group VIB are inorganic salts of Mo and / or W, and the inorganic salts of Mo and / or W are one or more of ammonium molybdate and ammonium tungstate; the metal compounds containing Group VIII are inorganic salts of metallic Ni and / or Co, and the inorganic salts of Ni and / or Co are one or more of nickel nitrate, basic nickel carbonate, cobalt nitrate, and basic cobalt carbonate.

19. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The precursor of alumina in step (2) is an organic aluminum-containing compound and / or an inorganic aluminum-containing compound. The organic aluminum-containing compound is one or more of alkyl aluminum and alkoxy aluminum. The alkyl aluminum is at least one of trimethyl aluminum, triethyl aluminum, tripropyl aluminum, and triisobutyl aluminum. The alkoxy aluminum has 3 to 20 carbon atoms and is selected from at least one of triethanolamine aluminum, tripropoxide aluminum, triisopropoxide aluminum, and tri-n-butoxy aluminum. The inorganic aluminum-containing compound is one or more of aluminum sulfate, aluminum nitrate, aluminum chloride, and sodium aluminate.

20. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The dispersant in step (2) is one or more of ethylene glycol monomethyl ether, ethylene glycol phenyl ether, ethylene glycol isopropyl ether, propylene glycol methyl ether, tripropylene glycol methyl ether, dipropylene glycol methyl ether, and propylene glycol butyl ether.

21. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The hydrolysis reaction conditions in step (2) are as follows: the hydrolysis temperature is 40-90℃, the pH value is controlled at 4.0-8.5, and the hydrolysis time is 0.5-5h.

22. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The supercritical drying process in step (3) uses carbon dioxide as the drying medium, with a pressure of 1 to 15 MPa, a drying temperature of 20 to 100°C, and a flow rate of 40 to 500 liters per hour.

23. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The drying conditions in step (4) are as follows: the drying temperature is 50 to 180°C and the drying time is 1 to 24 hours.

24. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The drying conditions in step (4) are as follows: the drying temperature is 80-150℃ and the drying time is 3-12h.

25. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The roasting conditions in step (4) are as follows: roasting temperature is 400℃~800℃, and roasting time is 1~12h.

26. The method for preparing the residue hydrotreating catalyst according to claim 7, characterized in that: The roasting conditions in step (4) are as follows: roasting temperature is 450℃~650℃, and roasting time is 3~8h.

27. A method for treating residual oil with hydrogen, wherein, in the presence of the residual oil hydrogenation catalyst as described in any one of claims 1-6, the residual oil is contacted with hydrogen to react.

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