Hydrodemetallization catalyst as well as preparation method and application thereof

Abstract

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

Description

Technical Field

[0001] The present invention relates to a hydrodemetallization catalyst, in particular to a hydrodemetallization catalyst suitable for use in a residual oil hydrotreating process, a preparation method thereof and an application thereof. Background Art

[0002] In recent years, crude oil resources have become increasingly scarce, and the trend of crude oil becoming heavier and inferior has become increasingly serious. Many refineries are adapting to the economic development situation and looking for methods that can effectively convert heavy oil into light products. Hydrogenation technology, as an important route for lightening heavy oil, is also facing new challenges and new problems under the current situation. Residue oil hydrotreating technology is an important means of lightening heavy oil in the oil refining process. The key to its development lies in the research and development of catalysts with good activity and stability. The hydrodemetallization catalyst is located before the hydrodesulfurization agent and the hydrodecarbonization agent, and carries the important function of removing various metal impurities (mainly Ni and V) in the raw materials, thereby ensuring the overall effect of the entire hydrogenation process. Therefore, it is particularly important to develop a hydrodemetallization catalyst with suitable activity and good stability.

[0003] CN105709765A discloses a preparation method of a residual oil hydrodemetallization catalyst, comprising the following steps: (1) kneading a pore-enlarging agent, pseudo-boehmite dry rubber powder, an extrusion aid, and a peptizing agent into a plastic body, extruding and drying; (2) subjecting the dried support in step (1) to unsaturated spray impregnation with a mixed solution of phosphoric acid and ammonium oxalate, subjecting the impregnated support to a sealed heat treatment, wherein the treatment pressure is the autogenous pressure under sealed conditions, the treatment temperature is 120-160° C., and the treatment time is 6-12 hours, and the treated support is dried and calcined to obtain an alumina support; (3) impregnating the alumina prepared in step (2) with an active component, and drying and calcining the impregnated support to obtain an alumina support for the residual oil hydrodemetallization catalyst.

[0004] CN1206037A discloses a residual oil hydrodemetallization catalyst. The method of the present invention is characterized in that a physical pore-expanding agent and a chemical pore-expanding agent are added simultaneously during the preparation of an alumina carrier, and the active component is loaded onto the carrier by spray impregnation. The pore volume of the catalyst is 0.80-1.20 mL / g and the specific surface area is 110-200 m 2 / g, and the pore diameter can be 15 to 20 nm.

[0005] CN1289640A discloses a method for preparing a supported hydrodemetallization catalyst. The method comprises placing a macroporous delta and / or theta phase alumina carrier in a spray tumbler, preparing an ammonia solution or aqueous solution of a Group VIB metal compound and / or a Group VIII metal compound, and uniformly spraying the carrier in an atomized form. The sprayed catalyst is then directly fed into a calcining furnace at a temperature of 300-450°C, then gradually heated to 460-550°C and maintained at this temperature in the presence of air for 1-5 hours.

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

[0007] To address the deficiencies in the prior art, the present invention provides a hydrodemetallization catalyst, a preparation method, and an application thereof. The catalyst is used in the hydrodemetallization process of residual oil and has high hydrodemetallization activity and metal-tolerance capacity, ensuring long-term operation of the device.

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

[0009] In the present invention, the first active metal is at least one Group VIII metal, preferably nickel. The second active metal includes molybdenum (the main active metal) and at least one Group VIII metal (the auxiliary active metal), wherein the Group VIII metal is preferably nickel.

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

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

[0012] In the present invention, the specific surface area of ​​the catalyst is 140 to 210 m 2 / g, and a pore volume of 0.50 to 1.25 mL / g; preferably, the specific surface area of ​​the catalyst is 150 to 180 m 2 / g, and the pore volume is 0.70~1.00mL / g.

[0013] In the present invention, the catalyst further comprises an auxiliary component, which is selected from at least one of fluorine, phosphorus, silicon or boron, preferably phosphorus. The content of the auxiliary component in the catalyst as oxide is 2.0% to 11.0% based on the mass of the catalyst.

[0014] The second aspect of the present invention provides a method for preparing the above-mentioned hydrodemetallization catalyst, comprising the following steps:

[0015] (1) impregnating activated carbon with a first active metal impregnation solution containing a dispersing aid, drying, and calcining to obtain modified activated carbon A;

[0016] (2) mixing the modified activated carbon A obtained in step (1) with an alkaline auxiliary agent, grinding, and drying to obtain modified activated carbon B;

[0017] (3) mixing pseudo-boehmite, the modified activated carbon B obtained in step (2), and an adhesive, forming the mixture, drying, and calcining the mixture to obtain a carrier C;

[0018] (4) Carrier C is subjected to surface carbon coating treatment, followed by drying and calcination to obtain carrier D;

[0019] (5) impregnating the support D obtained in step (4) with the second active metal impregnation solution and allowing the solution to stand to obtain a catalyst precursor;

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

[0021] In step (1), the dispersing aid is silica sol, wherein the mass content of silicon dioxide in the silica sol is 20.0% to 50.0%.

[0022] In step (1), the first active metal is at least one Group VIII metal, preferably nickel, and the nickel source is selected from at least one of basic nickel carbonate, nickel nitrate, and nickel sulfate. Furthermore, the first active metal impregnation solution contains 2.0% to 15.0% by weight of the first active metal oxide, and the dispersing aid contains 0.5% to 5.0% by weight of silicon dioxide.

[0023] In step (1), the activated carbon is high-temperature activated carbon. The lowest heat-resistant temperature of the high-temperature activated carbon is 750° C. The particle size of the activated carbon is 0.1 to 6.0 μm.

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

[0025] In step (1), the drying conditions are: temperature of 120-180° C., drying time of 4-8 hours. The calcination conditions are: temperature of 550-750° C., time of 3-8 hours, and calcination atmosphere of 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 acid properties of the support, and can also synergize with the main active metal (Mo) in the second active metal component to facilitate the hydrogenation reaction.

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

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

[0029] In step (2), the grinding can be performed by ball milling, sand milling, or other treatment methods. Not only does the metal dispersion of the ground material become more uniform, but the alkaline additive also forms a "first layer of protective film" on the surface of the dried material during the molding process in step (3). After grinding, the ground sample has an average particle size of 2.0 to 8.0 μm.

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

[0031] In step (3), the pseudo-boehmite is prepared by conventional methods, such as aluminum sulfate method, aluminum alcohol method, sol-gel method, etc. The mass content of aluminum oxide in the pseudo-boehmite is 65.0% to 80.0%.

[0032] In step (3), the adhesive may be an inorganic acid and / or an organic acid, the inorganic acid may be one or more of nitric acid, sulfuric acid, boric acid, and phosphoric acid, and the organic acid may 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 the pseudo-boehmite calculated as alumina and the modified activated carbon B.

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

[0035] In step (3), according to the molding requirements, a molding aid, such as at least one of an extrusion aid and deionized water, can be added during the molding process. The extrusion aid can be one or more of methyl cellulose, ethyl cellulose, sesbania powder, and starch. The mass of the extrusion aid added is 0.5% to 8.0% of the total mass of the pseudo-boehmite calculated as alumina and the modified activated carbon B. The amount of deionized water used can be 80% to 120% of the total mass of the pseudo-boehmite calculated as alumina and the modified activated carbon B.

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

[0037] In step (3), the calcination process adopts programmed temperature increase with a heating rate of 1°C / min to 3°C / min. The calcination temperature is 550°C to 750°C, 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, wherein the mass content of the polymer compound in the aqueous emulsion is 8.0% to 16.0%, and the mass content of the water-soluble cellulose is 0.5% to 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 amount of the aqueous emulsion (measured by volume mL) and the carrier C (measured by mass g) is 0.8 to 1.5 mL / g.

[0042] In step (4), the drying conditions are: drying temperature of 120-200°C, drying time of 2.0-12.0 hours. The calcination conditions are: calcination temperature of 500-700°C, calcination time of 2.0-8.0 hours, and calcination atmosphere of 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 Group VIII metal (preferably Ni), wherein the molybdenum is derived from one or both of molybdenum oxide and ammonium heptamolybdate, and the nickel is derived from one or both of basic nickel carbonate and nickel nitrate. The contents of MoO3 and the Group VIII metal (as oxide) in the second active metal impregnation solution are 10.0-50.0 g / 100 mL and 2.0-20.0 g / 100 mL, respectively. The mass of the Group VIII metal (as oxide) introduced into the catalyst by the second active metal impregnation solution accounts for 40.0%-70.0% of the total Group VIII metal loading (as oxide) in the catalyst.

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

[0045] In step (5), preferably, the second impregnation solution further 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 the water-soluble polymer J in the second active metal impregnation solution is 0.5 to 3.5 g / 100 mL.

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

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

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

[0049] In step (6), the calcination adopts a two-stage calcination process, wherein the first stage calcination temperature is 350-450° C., the calcination time is 2-6 hours, and the calcination atmosphere is one or more of air, nitrogen, or water vapor, preferably air; the second stage calcination temperature is 450-750° C., the calcination time is 2-8 hours, and the calcination atmosphere is one or more of air, nitrogen, or water vapor, preferably nitrogen. The second stage calcination temperature is 150-250° C. higher than the first stage calcination temperature.

[0050] The third aspect of the present invention provides the use of the above catalyst in the hydroprocessing of heavy oil and residual oil.

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

[0052] Residue oil hydrodemetallization catalyst is a bifunctional catalyst. During the reaction, hydrogenation and cracking reactions occur on the catalyst surface. Generally speaking, when the acidity of the catalyst surface is too strong, the hydrogenated product will continue to crack on the catalyst surface, and then condense and produce coke, which affects the activity of the catalyst. Therefore, the acidity of the catalyst surface plays an important role in the distribution of residue oil hydrogenation products and the long-term operation of the device. After extensive research, the inventors found that first impregnating the active metal Ni in the form of metal ions on the surface of activated carbon and then molding it with pseudo-boehmite can effectively reduce the interaction between the metal and the alumina support, while reducing the acidity of the catalyst surface and reducing the overall cracking performance of the catalyst. Secondly, the second active metal Mo is further introduced into the catalyst by saturated impregnation. The active metal of the second impregnation makes the catalyst still have 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, and the purpose of the second impregnation is to further regulate the hydrogenation activity of the catalyst surface. The present invention introduces active metals twice, 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; while improving the overall performance of the catalyst, it is beneficial to extend the operating cycle of the device.

[0053] Conventional active metal loading is a single impregnation process, and most of the active metal is distributed on the surface of the catalyst, resulting in a violent reaction on the catalyst surface. It is difficult for macromolecular reactants to enter the interior of the demetallization catalyst, which limits the utilization rate of the active metal. In addition, during the sulfurization process, the aggregated active metal has a low degree of sulfurization of the main metal due to the aggregation of the metal, and the hydrogenation capacity of the active metal is limited. The present invention introduces the active metal by two impregnations. In order to further weaken the interaction between the auxiliary metal nickel and the dry powder during the grinding and kneading process, the auxiliary metal nickel is first loaded on the activated carbon in the form of an impregnation. During this process, a dispersing aid is introduced to prevent the metal from aggregating during the roasting process of the nickel-containing activated carbon, allowing the metal to be evenly distributed on the activated carbon first. Secondly, during the grinding process, the alkaline additive introduced on the activated carbon will form a "protective film" during the kneading and molding process, reducing the interaction between nickel and alumina. Then, a carbon film treatment is performed on the support containing the auxiliary metal. After the carbon film is formed, it can ensure that the main metal molybdenum does not contact the auxiliary metal nickel and the support during the subsequent impregnation process, and the main metal molybdenum can be evenly dispersed on the carbon film. Finally, during calcination in a mixed atmosphere, the air removes the carbon film, leaving the primary metal, molybdenum, evenly dispersed on the carrier. This method not only further weakens the interaction between the metal and the carrier, but also effectively avoids the uneven distribution of the active metal due to competitive adsorption on the carrier surface during mixed impregnation of the two metals. Furthermore, a carbon coating treatment is performed on the carrier C, followed by calcination with an inert gas. The water gradually evaporates, and the latex particles are gradually squeezed to form a thin film. The structure contains crosslinkable groups, which crosslink to form a three-dimensional network film. This film temporarily provides a loading site for the second active metal. After the catalyst is calcined, the film disappears, and the second active metal is evenly dispersed on the carrier, cooperating with the first active metal, thereby improving the activity and stability of the hydrodemetallization process. During calcination in a mixed atmosphere, the air removes the carbon layer, allowing the primary active metal to be evenly loaded, while the water vapor ensures that the catalyst's pores are further unobstructed.

[0054] In summary, the method of the present invention achieves significant improvements in the activity and stability of the residue hydrodemetallization catalyst obtained through comprehensive coordination of various steps. DETAILED DESCRIPTION

[0055] The technical solutions and effects of the present invention are further described below with reference to the following embodiments, but are not limited to the following embodiments.

[0056] In the present invention, the ASAP-2420 physical adsorption instrument produced by Michael Company is used to characterize the pore structure and specific surface area of ​​the catalyst.

[0057] Example 1

[0058] (1) 54.09 g of a first active metal nickel (nickel nitrate), a dispersing agent (42.0 g of 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 with the solution. The first active metal impregnation solution had a nickel content of 3.60% by mass as oxide and a dispersing agent content of 3.72% by mass as silica. After impregnation, the solution 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 3.5 g of an alkaline additive (NaOH), ground (to a particle size of 5.0 μm), and dried at 140° C. for 5 h to obtain modified activated carbon B;

[0060] (3) 364.6 g of pseudo-boehmite (alumina content of 72.0% by mass), 37.5 g of modified activated carbon B, 5.47 g of nitric acid, 8.0 g of sesbania powder, and 360.0 g of deionized water were mixed and kneaded, and then extruded into a four-leaf clover shape. The mixture was then dried at 150°C for 5 h and calcined at 700°C for 4 h to obtain support C.

[0061] (4) Carrier C was subjected to surface carbon coating treatment using an aqueous emulsion containing polyimide and hydroxymethyl cellulose, wherein the mass content of polyimide in the aqueous emulsion was 9.0% and the mass content of hydroxymethyl cellulose was 1.5%. The amount of aqueous emulsion (by volume mL) to carrier C (by mass g) was 1.5 mL / g. After drying at 180°C for 6 h, the carrier was calcined at 650°C for 5 h under a nitrogen atmosphere. After calcination, a thin film with a three-dimensional network structure was formed on the surface of carrier C, obtaining carrier D.

[0062] (5) impregnating the support D with a second active metal impregnation solution by saturation impregnation, wherein the content of MoO3 in the second active metal impregnation solution is 16.86 g / 100 mL, the content of NiO is 3.42 g / 100 mL, the content of phosphoric acid is 8.11 g / 100 mL, and the content of polyacrylamide is 0.50 g / 100 mL. After standing for 24 hours, a catalyst precursor is obtained;

[0063] (6) The catalyst precursor obtained in step (5) was dried at 120°C for 6 hours and calcined in a two-stage process. The first stage was calcined at 400°C for 4 hours in an air atmosphere; the second stage was calcined at 650°C for 6 hours in a nitrogen atmosphere. Finally, the hydrodemetallization 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), a dispersing agent (27.9 g of silica sol, with a silicon dioxide content of 30% by mass), and water are prepared into an impregnation solution, and 297.0 g of high-temperature activated carbon is saturated with the solution. The nickel content in the first active metal impregnation solution is 2.40% by mass, and the dispersant content in the form of silicon dioxide is 2.47% by mass. In step (5), the second active metal impregnation solution has a MoO3 content of 16.71 g / 100 mL, a NiO content of 4.71 g / 100 mL, a phosphoric acid content of 8.01 g / 100 mL, and a polyacrylamide content of 0.50 g / 100 mL, and the carrier D is saturated with the solution. Finally, a hydrodemetallization catalyst CAT-2 is prepared. 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 surface of Carrier C is carbon-coated using an aqueous emulsion containing polyimide and hydroxymethyl cellulose, with the polyimide content being 12.0% by mass and the hydroxymethyl cellulose content being 2.5% by mass. The amount of aqueous emulsion (by volume, mL) to Carrier C (by mass, g) is 1.2 mL / g. The calcination conditions are: calcination at 550°C for 6 h under a nitrogen atmosphere. After calcination, a thin film with a three-dimensional network structure is formed on the surface of Carrier C, yielding Carrier D. Finally, the hydrodemetallization catalyst CAT-3 is prepared. 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 pseudo-boehmite (alumina content of 72.0% by mass), 33.3 g of modified activated carbon B, 6.25 g of nitric acid, 6.0 g of sesbania powder, and 340.0 g of deionized water are mixed and kneaded, and then extruded into a four-leaf clover shape. The mixture is then dried at 120°C for 8 h and calcined at 650°C for 6 h to obtain carrier C. Finally, hydrodemetallization catalyst CAT-4 is prepared. 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 adopt a step-by-step calcination process. The calcination temperature is 500°C, the calcination time is 3 hours, and the calcination atmosphere is air. Finally, the hydrodemetallization catalyst DAT-1 is prepared. Other physicochemical properties and composition of the catalyst are shown in Table 2.

[0072] Comparative Example 2

[0073] Compared with Example 1, the difference is that the amount of the first active metal nickel (nickel nitrate) in step (1) is changed to 69.78 g, and an impregnation solution is prepared to saturate 297.0 g of high-temperature activated carbon. The mass content of nickel in the first active metal impregnation solution as oxide is 4.64%, and the mass content of the dispersing agent as silicon dioxide is 3.72%. The second active metal impregnation solution in step (5) does not contain nickel. Finally, the hydrodemetallization catalyst DAT-2 is prepared. 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 in step (5), the carrier D is impregnated with the second active metal impregnation solution by saturation impregnation. The second active metal impregnation solution has a MoO3 content of 16.69 g / 100 mL, a NiO content of 7.40 g / 100 mL, and an amount of phosphoric acid added of 8.11 g / 100 mL. 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 prepared. 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 dispersing agent is added in step (1). No alkaline agent is added in step (2). Finally, the hydrodemetallization catalyst DAT-4 is prepared. 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 10.5% by weight glucose aqueous solution, and the amount 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. 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, that is, the surface carbon coating treatment is not performed. Finally, the hydrodemetallization catalyst DAT-6 is prepared. 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 No. 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] The activity stability tests of Examples 1 to 4 and Comparative Examples 1 to 6 were carried out on a 200 mL fixed bed hydrogenation test apparatus. The raw oil was residual oil with a density of 987.3 g / m 3 (20°C), S content 2.20 wt%, Ni and V contents 31.7 μg / g and 62.9 μg / g, respectively, CCR content 12.2 wt%. The demetallization rate after 2000 h of operation in Example 1 is 100%, and all other values ​​are relative demetallization rates. Specific test conditions are shown in Table 3, and test results are shown in Tables 4 and 5.

[0089] Table 3 Test conditions

[0090]

[0091]

[0092] Table 4 Test results of hydrodemetallization catalysts of various embodiments

[0093]

[0094] Table 5 Test results of the hydrodemetallization catalysts of the comparative examples

[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, and has high hydrogenation activity and stability, and can well meet the requirements of the residue hydrodemetallization process.

Claims

1. A hydrodemetallization catalyst, comprising a carrier and a second active metal, wherein the carrier comprises alumina, activated carbon and a first active metal, wherein: The mass ratio of aluminum oxide to activated carbon is 4 to 12:1, preferably 6 to 9:

1.

2. The catalyst according to claim 1, characterized in that: The first active metal is at least one of the Group VIII metals, preferably nickel; the second active metal includes molybdenum and at least one selected from the Group VIII metals, wherein the Group VIII metal is preferably nickel.

3. The catalyst according to claim 1, characterized in that: Based on the mass of the catalyst, the content of MoO3 is 9.0% to 35.0%, and the content of the Group VIII metal oxide is 5.0% to 16.0%.

4. The catalyst according to claim 2 or 3, characterized in that: The content of the Group VIII metal in the first active metal as oxide is 30.0% to 60.0% of the total Group VIII metal loading in the catalyst as oxide, and the content of the Group VIII metal in the second active metal as oxide is 40.0% to 70.0% of the total Group VIII metal loading in the catalyst as oxide.

5. The catalyst according to claim 1, characterized in that: The specific surface area of ​​the catalyst is 140 to 210 m 2 / g, pore volume is 0.50~1.25mL / g; Preferably, the specific surface area of ​​the catalyst is 150 to 180 m 2 / g, and the pore volume is 0.70~1.00mL / g.

6. The catalyst according to claim 1, characterized in that: The catalyst includes an auxiliary component, which is selected from at least one of fluorine, phosphorus, silicon or boron, preferably phosphorus; And / or, in the catalyst, the content of the auxiliary component in terms of oxide is 2.0% to 11.0% based on the mass of the catalyst.

7. A method for preparing the catalyst according to any one of claims 1 to 5, comprising the steps of: (1) impregnating 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 auxiliary agent, grinding, and drying to obtain modified activated carbon B; (3) Pseudo-boehmite, the modified activated carbon B obtained in step (2), and an adhesive are mixed, molded, dried, and calcined to obtain a carrier C; (4) Carrier C is subjected to surface carbon coating treatment, and then dried and calcined to obtain carrier D; (5) impregnating the support D obtained in step (4) with the second active metal impregnation solution and allowing to stand to obtain a catalyst precursor; (6) The catalyst precursor obtained in step (5) is dried and calcined to obtain the hydrodemetallization catalyst.

8. The preparation method according to claim 7, characterized in that: In step (1), the dispersing aid is silica sol, and preferably, the mass content of silicon dioxide in the silica sol is 20.0% to 50.0%; And / or, in step (2), the alkaline auxiliary agents are independently selected from one or more of sodium hydroxide, potassium hydroxide, and sodium carboxylate; And / or, in step (3), the adhesive 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.

9. The preparation method according to claim 7, characterized in that: In step (1), the first active metal is at least one of the Group VIII metals, preferably nickel; and / or, in the first active metal impregnation solution, the mass content of the first active metal oxide is 2.0% to 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% to 5.0%.

10. The preparation method according to claim 7, characterized in that: In step (2), the mass ratio of the alkaline auxiliary agent to the activated carbon used in step (1) is 0.01 to 0.10; And / or, in step (3), the mass of the adhesive is 0.5% to 5.0% of the total mass of the pseudo-boehmite calculated as alumina and the modified activated carbon B, Optionally, in step (3), an extrusion aid is added during the molding process; wherein the mass of the extrusion aid is 0.5% to 8.0% of the total mass of the pseudo-boehmite calculated as alumina and the modified activated carbon B; Preferably, in step (3), the extrusion aid is one or more of methyl cellulose, ethyl cellulose, sesbania powder, and starch.

11. The preparation method according to claim 7, characterized in that: In step (1), the calcination conditions are: temperature of 550-750° C., time of 3-8 hours, and calcination atmosphere of one or more of air, water vapor, and nitrogen; And / or, in step (3), the calcination conditions are: temperature of 550-750° C., time of 2-8 h, and calcination atmosphere of one or more of air, nitrogen, or water vapor, preferably air; And / or, in step (4), the calcination conditions are: temperature of 500-700°C, time of 2.0-8.0h, calcination atmosphere of inert atmosphere, wherein the inert atmosphere is one or more of nitrogen and argon.

12. The preparation method according to claim 7, characterized in that: In step (4), the carbon coating treatment uses an aqueous emulsion containing a polymer compound and water-soluble cellulose; the polymer compound is one or more of polyimide, polyfurfuryl alcohol, and phenolic resin; the water-soluble cellulose is one or more of hydroxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, and hydroxyethyl cellulose.

13. The preparation method according to claim 12, characterized in that: In the aqueous emulsion, the mass content of the polymer compound is 8.0% to 16.0%, and the mass content of the water-soluble cellulose is 0.5% to 3.5%; And / or, the amount of the aqueous emulsion in mL by volume and the carrier C in g by mass is 0.8 to 1.5 mL / g.

14. The preparation method according to claim 7, characterized in that: The second active metal impregnation solution is an impregnation solution containing Mo and at least one selected from Group VIII metals; Preferably, the second impregnation solution further includes at least one auxiliary agent selected from the group consisting of fluorine, phosphorus, silicon and boron; Preferably, the second impregnation liquid further contains a water-soluble polymer J, and the water-soluble polymer J is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylamide, methyl cellulose and the like.

15. The preparation method according to claim 14, characterized in that: The contents of MoO3 and Group VIII metal in the second active metal impregnation solution as oxides are 10.0-50.0 g / 100 mL and 2.0-20.0 g / 100 mL, respectively; and / or, the mass of the Group VIII metal introduced into the catalyst by the second active metal impregnation solution as oxide accounts for 40.0% to 70.0% of the total Group VIII metal loading as oxide in the catalyst; and / or, the amount of the additive added in the second impregnation solution in terms of oxide is 2.0 to 20.0 g / 100 ml, preferably 5.0 to 15.0 g / 100 ml; And / or, the content of the water-soluble polymer J in the second active metal impregnation solution is 0.5 to 3.5 g / 100 ml.

16. The preparation method according to claim 7, characterized in that: In step (6), the calcination adopts a two-stage calcination process, the first stage calcination temperature is 350-450° C., the calcination time is 2-6 hours, and the calcination atmosphere is one or more of air, nitrogen, or water vapor, preferably air; the second stage calcination temperature is 450-750° C., the calcination time is 2-8 hours, and the calcination atmosphere is one or more of air, nitrogen, or water vapor, preferably nitrogen; Preferably, the second stage roasting temperature is 150-250° C. higher than the first stage roasting temperature.

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