A catalyst for hydrodemetallization of residue oil and its preparation method

Abstract

This invention discloses a catalyst for hydrodemetallization of heavy and residual oils and its preparation method. The catalyst comprises an alumina support and a second active metal component. The alumina support contains a first active metal component, which is dispersed within the bulk phase of the alumina support. The mass ratio of the first active metal component (based on oxides) to the alumina support is 0.01–0.10:1. When used in the hydrodemetallization reaction of heavy and residual oils, this catalyst significantly improves its resistance to carbon deposition, demetallization activity, and metal-containing capacity, ensuring long-term stable operation of the unit.

Description

Technical Field

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

[0002] With the increasing severity and deterioration of crude oil quality, coupled with the growing market demand for light oil products, heavy oil hydrotreating technology has gradually become a focus of attention in the petrochemical industry. Fixed-bed residue hydrotreating technology, with its advanced technology and wide range of applications, is an important means to achieve clean and efficient utilization of vacuum residue. However, due to the presence of metals and other heteroatoms in the residue, the hydrotreating catalyst is prone to deactivation during the reaction process due to the deposition of metals and carbon deposits. Since the demetallization catalyst occupies a relatively prominent position in the fixed-bed residue hydrotreating catalyst gradation system and bears a significant reaction load, developing a hydrotreating catalyst with a longer lifespan and better hydrotreating performance, especially a hydrodemetallization catalyst, is particularly important.

[0003] Currently, research on hydrogenation demetallization catalysts mainly focuses on the pore size of the support, such as introducing pore-expanding agents and acid treatment during the support preparation process. However, the acidity distribution on the surface of the support prepared by these methods is uneven, and the introduction of additives destroys the original pores of the support, which is not conducive to the dispersion of active metals in the subsequent impregnation process. As a result, the catalyst has poor hydrogenation performance, poor resistance to metal deposition, and poor resistance to carbon buildup.

[0004] CN104549331A discloses a method for preparing a hydrogenation demetallization catalyst, comprising the following steps: (1) preparing a mixture of alumina dry adhesive powder and water; (2) treating the material obtained in step (1) with dual-frequency microwaves at a temperature of 100-300℃, preferably 150-250℃, for a time of 1-6h, preferably 2-4h, with a frequency difference of 1-50kHz, preferably 5-35kHz, and filtering and drying after treatment; (3) mixing the material obtained in step (2) with a salt solution containing active metal, and then drying and calcining to obtain the hydrogenation demetallization catalyst.

[0005] CN104646007A discloses a residue oil hydrodemetallization catalyst and its preparation and application. First, an activated carbon support undergoes two pretreatment processes: hydrochloric acid washing and nitric acid oxidation. Then, a composite additive, activated carbon, and alumina are mixed and extruded to prepare an activated carbon / alumina composite. Finally, metal is loaded onto the support using a hydrotalcite method, i.e., an equal volume of a mixed solution of terephthalic acid, nickel nitrate, urea, and ammonium nitrate in a molar ratio of 2:1:(2.5-5):(1-5) is impregnated, crystallized, washed several times, and dried to obtain nickel salt talc microcrystals. These microcrystals are then placed in a Mo salt solution for complete displacement, filtered, washed, and dried to obtain green solid particles, which are then calcined to obtain the residue oil hydrodemetallization catalyst.

[0006] 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.

[0007] The hydrogenation activity and stability of the hydrogenation demetallization catalyst prepared by the above method need to be further improved. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a catalyst for the hydrodemetallization of heavy and residual oils and its preparation method. When used in the hydrodemetallization reaction of heavy and residual oils, this catalyst exhibits strong hydrogenation activity, significantly improved anti-carbon deposition performance, demetallization activity, and metal-containing capacity, ensuring long-term stable operation of the equipment.

[0009] The first aspect of the present invention provides a residue oil hydrodemetallization catalyst, the catalyst comprising an alumina support and a second active metal component, wherein the alumina support contains a first active metal component, the first active metal component being dispersed in the bulk phase of the alumina support; the mass ratio of the first active metal component, calculated as oxide, to the mass of the alumina support is 0.01 to 0.10:1.

[0010] In this invention, the first active metal is at least one of Group VIII metals, preferably nickel. The second active metal component includes molybdenum and at least one selected from Group VIII metals, preferably nickel.

[0011] In this invention, based on the mass of the catalyst, the content of MoO3 is 10.0% to 28.0%, and the content of Group VIII metal oxides is 2.0% to 20.0%. The mass ratio of Group VIII metal oxides in the first active metal component to that in the second active metal component is 0.5 to 1.5:1.

[0012] In this invention, the catalyst has a specific surface area of ​​160–210 m². 2 / g, with a pore volume of 0.50–0.90 mL / g; preferably, the catalyst has a specific surface area of ​​160–190 m² / g. 2 / g, with a pore volume of 0.60~0.80mL / 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. Further, based on the mass of the catalyst, the content of the auxiliary component, calculated as oxides, is 1.0% to 6.0%.

[0014] A second aspect of this invention provides a method for preparing a residue oil hydrodemetallization catalyst, comprising the following steps:

[0015] (1) Mix boehmite, first active metal, alkaline additive and deionized water, grind and filter to obtain solid material A;

[0016] (2) The solid material A obtained in step (1) is mixed with an adhesive, shaped, dried and calcined to obtain a pre-carrier containing the first active metal.

[0017] (3) The pre-carrier obtained in step (2) is subjected to surface carbon coating treatment and calcined to obtain carrier B with surface carbon coating film;

[0018] (4) Impregnate the carrier B obtained in step (3) with the second active metal impregnation solution to obtain carrier C;

[0019] (5) The support C obtained in step (4) is dried and calcined to obtain the catalyst.

[0020] In step (1), the pseudoboehmite is prepared using conventional methods, such as the aluminum sulfate method, the aluminum alkoxide method, and the sol-gel method. The alumina content in the pseudoboehmite is 60.0%–75.0% by mass.

[0021] In step (1), the alkaline auxiliary agent is one or more alkaline compounds such as sodium hydroxide, potassium hydroxide, and sodium carboxylate (e.g., sodium acetate, sodium formate).

[0022] In step (1), the first active metal is at least one of Group VIII metals. Preferably, the Group VIII metal is Ni, and the Ni source is selected from at least one of basic nickel carbonate, nickel sulfate, nickel nitrate, etc.

[0023] In step (1), the mass ratio of pseudoboehmite (calculated as alumina), first active metal (calculated as oxide), alkaline additive, and water is 200-240: 1.0-8.0: 6.0-15.0: 120-180.

[0024] In step (1), the grinding can be performed using methods such as ball milling or sand milling. 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. The filtration process is a standard operation in the field. After grinding, a ground sample with an average particle size of 2.0–10.0 μm is obtained.

[0025] In step (1), the first active metal 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.

[0026] In step (2), the adhesive can be an organic acid and / or an inorganic 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.

[0027] In step (2), the mass of the adhesive is 0.5% to 5.0% of the mass of boehmite in step (1) based on alumina.

[0028] In step (2), the forming method can be at least one of extrusion, sheet forming, and ball forming. The formed shape can be clover-shaped, four-leaf clover-shaped, butterfly-shaped, cylindrical, spherical, or strip-shaped, etc.

[0029] In step (2), 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 mass of boehmite (based on alumina). The amount of deionized water used can be 80% to 120% of the mass of boehmite (based on alumina) in step (1).

[0030] In step (2), the drying temperature is 120-200℃ and the drying time is 2-12h.

[0031] In step (2), the roasting process employs a two-stage roasting process. 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 150–300℃ higher than the first stage roasting temperature.

[0032] In step (3), 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 5.0% to 15.0%, and the water-soluble cellulose has a mass content of 0.5% to 3.0%.

[0033] In step (3), the polymer compound is one or more of polyimide, polyfurfuryl alcohol, phenolic resin, etc.

[0034] In step (3), the water-soluble cellulose is one or more of hydroxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, etc.

[0035] In step (3), the ratio of the amount of the aqueous emulsion (in mL) to the amount of the pre-carrier (in g) is 0.8 to 1.5 mL / g.

[0036] In step (3), after the surface carbon coating treatment is completed, it is first filtered, washed, and dried in a conventional manner. The drying temperature is 120-200℃, and the drying time is 2.0-12.0h. The calcination conditions are: temperature 500-700℃, time 2.0-8.0h, and the calcination atmosphere is an inert atmosphere, preferably one or more of nitrogen and argon.

[0037] In step (4), the second active metal includes Mo and at least one selected from Group VIII metals (preferably Ni). Further, in the second active metal impregnation solution, the Mo source can be one or both of molybdenum oxide and ammonium heptamolybdate, and the Ni source can be one or both of basic nickel carbonate and nickel nitrate. Further, in the second active metal impregnation solution, the content of Mo as MoO3 is 10.0–50.0 g / 100 mL, and the content of Group VIII metal as oxide is 3.0–20.0 g / 100 mL. The mass of Group VIII metal as oxide introduced into the catalyst by the second active metal impregnation solution accounts for 50.0%–80.0% of the total Group VIII metal oxide loading in the catalyst.

[0038] In step (4), at least one additive containing fluorine, phosphorus, silicon or boron may be introduced into the second active metal impregnation solution, and the content of the additive in the second active metal impregnation solution is 3.0 to 18.0 g / 100 mL.

[0039] In step (4), preferably, the second active metal impregnation solution 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 0.5–2.5 g / 100 mL.

[0040] In step (4), the impregnation method is saturated impregnation.

[0041] In step (5), the drying temperature is 120-200℃ and the drying time is 2-12h.

[0042] In step (5), the roasting process is carried out at a temperature of 550 to 750°C and a roasting time of 2 to 10 hours. The roasting is carried out in a mixed atmosphere of air and water vapor, wherein the volume ratio of air to water vapor is 0.1 to 5.0:1.0.

[0043] In step (5), the catalyst, based on catalyst mass, has a MoO3 content of 10.0% to 28.0% and a group VIII metal oxide content of 2.0% to 20.0%.

[0044] In step (5), the mass ratio of the first active metal component introduced into the catalyst as an oxide of a Group VIII metal to the second active metal component introduced into the catalyst as an oxide of a Group VIII metal is 0.5 to 1.5:1.

[0045] In step (5), preferably, the content of the additive, calculated as oxide, in the catalyst is 1.0% to 6.0% based on the mass of the catalyst.

[0046] The third aspect of this invention provides the application of the above-mentioned catalyst in the hydrotreating of heavy oil and residual oil.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] Conventional active metal loading involves a single impregnation, resulting in most active metals being distributed on the catalyst surface. This leads to intense surface reactions and hinders the penetration of large molecular reactants into the hydrogenation demetallization catalyst, limiting the utilization rate of the active metal. Furthermore, the aggregated active metals exhibit low sulfidation during the sulfidation process, further limiting their hydrogenation capacity. This invention introduces a portion of the active metal during the support preparation process, dispersing it within the alumina support bulk phase. This portion of the active metal forms a state where it is more abundant inside the alumina support than outside. During the reaction, this reduces the reaction intensity on the catalyst surface, increasing the ability of large molecules to penetrate further into the catalyst. It also improves the final sulfidation degree of the active metal on the catalyst, thereby enhancing its hydrogenation capacity. Adding a first active metal (co-active metal) during grinding ensures more uniform dispersion, and the protective film formed by the introduced alkaline additive weakens the interaction between nickel and alumina during support formation. Then, the aforementioned support is coated with a carbon film. The carbon film ensures that the Mo (the primary active metal) does not come into contact with the already loaded and dispersed first active metal (co-active metal) during the impregnation process, while the primary active metal is uniformly dispersed on the carbon film. Finally, after calcination in a mixed atmosphere, air is introduced to remove the carbon film, leaving the primary active metal uniformly dispersed on the support. This method 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 on the pre-support containing the first active metal, followed by calcination in an inert gas atmosphere, gradually evaporates moisture, 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 pre-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 primary active metal, while water vapor ensures further unobstructed pores in the catalyst.

[0049] In summary, the method of this invention, through the comprehensive coordination of each step, finally produces a heavy and residual oil hydrodemetallization catalyst with significantly improved anti-carbon deposition performance, demetallization activity, and metal-containing capacity, which can ensure the long-term stable operation of the equipment. Detailed Implementation

[0050] 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.

[0051] In this invention, the pore structure and specific surface area of ​​the catalyst are characterized using the Mack ASAP-2420 physical adsorption instrument.

[0052] Example 1

[0053] (1) Mix 300g of boehmite (alumina content 74.0%), 9.8g of basic nickel carbonate (nickel oxide content 52.0%), 10.5g of alkaline additive NaOH, and 150g of deionized water, grind (the average particle size of the sample after grinding is 5.0μm), filter, and obtain solid material A;

[0054] (2) The solid material A obtained in step (1) is mixed with 9.4g of nitric acid, 6.0g of guar gum powder and 200g of deionized water, and then extruded into a four-leaf clover shape. After drying and calcining (drying temperature is 120℃, drying time is 6h. The calcination process adopts two stages of calcination. The first stage of calcination temperature is 400℃, calcination time is 3h, and the calcination atmosphere is air; the second stage of calcination temperature is 650℃, calcination time is 3h, and the calcination atmosphere is nitrogen), a pre-carrier containing part of the active metal Ni is obtained.

[0055] (3) The pre-carrier was subjected to surface carbon coating treatment using an aqueous emulsion containing polyimide and hydroxymethyl cellulose. The mass content of polyimide in the aqueous emulsion was 8.0%, and the mass content of hydroxymethyl cellulose was 0.8%. The ratio of the aqueous emulsion (by volume mL) to the pre-carrier (by mass g) was 1.0 mL / g. After drying and calcination, the drying temperature was 150℃ and the drying time was 8 h. Calcination was carried out under a nitrogen atmosphere at a temperature of 650℃ for 5 h. After calcination, a three-dimensional network structure film was formed on the surface of the pre-carrier, resulting in carrier B.

[0056] (4) The carrier B obtained in step (3) is impregnated with the impregnation solution containing the second active metal in a saturated impregnation manner. The impregnation solution containing the second active metal contains 14.7 g / 100 mL of MoO3, 3.17 g / 100 mL of NiO, 9.16 g / 100 mL of phosphoric acid, and 2.0 g / 100 mL of polyacrylamide to obtain carrier C;

[0057] (5) The carrier C obtained in step (4) is dried at a temperature of 150°C for 4 hours and then calcined at 600°C for 4 hours. The calcination process is carried out in a mixed atmosphere with a volume ratio of air to water vapor of 1:2. Finally, the hydrogenation demetallization catalyst CAT-1 is obtained. The physicochemical properties and composition of the catalyst are shown in Table 1.

[0058] Example 2

[0059] Compared with Example 1, the difference is that in step (3), the pre-support 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 10.0%, and the mass content of hydroxymethyl cellulose is 1.2%. The ratio of the aqueous emulsion (by volume mL) to the pre-support (by mass g) is 1.3 mL / g. The calcination conditions are: calcination at 600℃ for 4 hours under a nitrogen atmosphere. After calcination, a three-dimensional network structure film can be formed on the surface of the pre-support, resulting in support B. Finally, the hydrogenation demetallization catalyst CAT-2 is obtained. The physicochemical properties and composition of the catalyst are shown in Table 1.

[0060] Example 3

[0061] Compared with Example 1, the difference is that in step (1), 300g of boehmite (alumina content 74.0%), 8.5g of alkaline additive NaOH, and 180g of deionized water were mixed; in step (2), 8.8g of nitric acid, 6.6g of guar gum powder, and 240g of deionized water were extruded into a four-leaf clover shape, and then dried at 120℃ for 6h. The first stage of calcination was at 450℃ for 4h in an air atmosphere; the second stage of calcination was at 650℃ for 4h in a nitrogen atmosphere. Finally, the hydrogenation demetallization catalyst CAT-3 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0062] Example 4

[0063] Compared with Example 1, the difference is that in step (3), the pre-support is subjected to surface carbon coating treatment, and an aqueous emulsion containing polyimide and hydroxymethyl cellulose is used. The mass content of polyimide in the aqueous emulsion is 12.0%, and the mass content of hydroxymethyl cellulose is 1.5%. The ratio of aqueous emulsion (by volume mL) to pre-support (by mass g) is 0.8 mL / g; the ratio of air to water vapor in the calcination atmosphere in step (5) is 2:1. Finally, the hydrodemetallization catalyst CAT-4 is obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0064] Example 5

[0065] Compared with Example 1, the difference is that in step (1), the first active metal, basic nickel carbonate, is 12.2 g (nickel oxide mass fraction is 52.0%); in step (4), the impregnation solution containing the second active metal has a MoO3 content of 14.7 g / 100 mL, a NiO content of 2.60 g / 100 mL, a phosphoric acid content of 9.16 g / 100 mL, and a polyacrylamide content of 2.0 g / 100 mL, and the support B obtained in step (3) is impregnated by saturation impregnation. Finally, the hydrodemetallization catalyst CAT-5 is obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0066] Example 6

[0067] Compared with Example 1, the difference is that the calcination process in step (2) adopts a two-stage step-by-step calcination. The first stage calcination temperature is 400℃, the calcination time is 5h, and the calcination atmosphere is air; the second stage calcination temperature is 700℃, the calcination time is 5h, and the calcination atmosphere is nitrogen, resulting in a pre-support containing some active metal Ni. Finally, the hydrogenation demetallization catalyst CAT-6 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 1.

[0068] Comparative Example 1

[0069] Compared with Example 1, the difference is that the calcination process in step (5) does not use a mixed atmosphere for 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. The physicochemical properties and composition of the catalyst are shown in Table 2.

[0070] Comparative Example 2

[0071] Compared with Example 1, the difference is that the solution used in the carbon coating process in step (3) is changed to a glucose aqueous solution with a mass percentage of 8.8%, and the ratio of glucose aqueous solution (volume in mL) to the pre-support (mass in g) is 1.0 mL / g. Finally, the hydrodemetallization catalyst DAT-2 was prepared, and the physicochemical properties and composition of the catalyst are shown in Table 2.

[0072] Comparative Example 3

[0073] Compared with Example 1, the difference lies in the forming process, that is, all nickel is introduced in step (1), and only metallic Mo and auxiliary agent P are introduced into the second impregnation solution. Finally, the hydrodemetallization catalyst DAT-3 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 2.

[0074] Comparative Example 4

[0075] Compared with Example 1, the difference is that the first active metal Ni is not added in step (1), and the amount of MoO3 introduced into the catalyst by the second impregnation liquid in step (4) is 100% of the total MoO3 loading in the catalyst, and the amount of NiO introduced into the catalyst by the second impregnation liquid is 100% of the total NiO loading in the catalyst. Finally, the hydrodemetallization catalyst DAT-4 was obtained, and the physicochemical properties and composition of the catalyst are shown in Table 2.

[0076] Comparative Example 5

[0077] Compared with Example 1, the difference is that no alkaline additive is introduced in the preparation of solid material A in step (1). The final hydrogenation demetallization catalyst DAT-5 is obtained, and its physicochemical properties and composition are shown in Table 2.

[0078] Comparative Example 6

[0079] Compared with Example 1, the difference is that step (3) is omitted, that is, the surface carbonization treatment is not performed, and instead the second active metal is directly impregnated. Finally, the hydrodemetallization catalyst DAT-6 was prepared, and the physicochemical properties and composition of the catalyst are shown in Table 2.

[0080] Table 1. Physicochemical properties and catalyst composition of each example of hydrodemetallization catalyst.

[0081]

[0082] Table 2 Physicochemical properties and catalyst composition of each comparative example of hydrogenation demetallization catalyst

[0083]

[0084]

[0085] Evaluation test

[0086] Activity stability tests were conducted on Examples 1-6 and Comparative Examples 1-6 using a 200mL fixed-bed hydrogenation test apparatus. The feedstock was residue oil with a density of 987.8 kg / m³. 3 (20℃), S content 2.35wt%, Ni and V contents 35.4μg / g and 64.1μg / g respectively, CCR content 12.6wt%, the demetallization rate was 100% after 2000h of operation in Example 1, and all other values ​​are relative demetallization rates. Specific experimental conditions are shown in Table 3, and experimental results are shown in Tables 4 and 5.

[0087] Table 3 Experimental conditions

[0088] Reaction temperature, °C 385 Reaction pressure, MPa 15.7 <![CDATA[Liquid hourly space velocity, h -1 > 1.0 Hydrogen-to-oil ratio, V / V 750

[0089] Table 4. Test results of the hydrogenation demetallization catalysts in each example.

[0090]

[0091] Table 5. Experimental results of hydrogenation demetallization catalysts in each comparative example.

[0092]

[0093] 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 heavy and residual oils.

Claims

1. A method for preparing a residue hydrodemetalization catalyst, the catalyst comprising an alumina carrier and a second active metal component, the alumina carrier containing a first active metal component dispersed in the bulk phase of the alumina carrier, the mass ratio of the first active metal component in terms of oxide to the mass of the alumina carrier being 0.01-0.10:1, the first active metal being at least one of Group VIII metals, the second active metal component comprising at least one of molybdenum and Group VIII metals, the method for preparing the catalyst comprising the following steps: (1) mixing pseudo-boehmite, the first active metal, an alkaline aid, deionized water, grinding, filtering to obtain a solid material A; (2) mixing the solid material A obtained in step (1) with a binder, shaping, drying, calcining to obtain a pre-carrier containing the first active metal; (3) performing a surface carbon coating treatment on the pre-carrier obtained in step (2), calcining to obtain a carrier B with a carbon coating film on the surface; (4) impregnating the carrier B obtained in step (3) with a second active metal impregnating solution to obtain a carrier C; (5) drying and calcining the carrier C obtained in step (4) to obtain the catalyst; in step (3), the carbon coating treatment uses an aqueous emulsion containing a high molecular compound and water-soluble cellulose; in step (5), the calcining uses a mixed gas atmosphere of air and water vapor. In step (1), the alkaline aid is one or more of sodium hydroxide, potassium hydroxide and sodium carboxylate; and / or, in step (2), the binder is an organic acid and / or an inorganic acid, the inorganic acid being one or more of nitric acid, sulfuric acid, boric acid and phosphoric acid, and the organic acid being one or more of tartaric acid, citric acid and oxalic acid; and / or, in step (3), the high molecular compound is one or more of polyimide, polyfurfuryl alcohol and phenolic resin, and the water-soluble cellulose is one or more of hydroxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose and hydroxyethyl cellulose. In the first active metal, the Group VIII metal is Ni, and the Ni source is selected from at least one of basic nickel carbonate, nickel sulfate and nickel nitrate. In step (1), the mass ratio of pseudo-boehmite in terms of alumina to the first active metal in terms of oxide to the alkaline aid to water is 200-240:1.0-8.0:6.0-15.0:120-180; and / or, in step (2), the mass of the binder is 0.5%-5.0% of the mass of pseudo-boehmite in terms of alumina in step (1); optionally, in step (2), an extrusion aid and deionized water are added during the shaping process, wherein the mass of the extrusion aid is 0.5%-8.0% of the mass of pseudo-boehmite in terms of alumina in step (1), and the amount of deionized water is 80%-120% of the mass of pseudo-boehmite in terms of alumina in step (1). The extrusion aid is one or more of methyl cellulose, ethyl cellulose, sesbania powder and starch. ​ ​ ​ ​ ​ ​ ​ 2. The method of claim 1, wherein: ​ ​ ​ 3. The method of claim 1, wherein: ​ 4. The method of claim 1, wherein: ​ ​ ​ 5. The method of claim 4, wherein: ​ 6. The method of claim 1, wherein: In step (2), the calcination adopts a two-stage calcination process, the first-stage calcination temperature is 350-450℃, the calcination time is 2-6h, and the calcination atmosphere is one or more of air, nitrogen, or water vapor; the second-stage calcination temperature is 450-750℃, the calcination time is 2-8h, and the calcination atmosphere is one or more of air, nitrogen, or water vapor.

7. The method of claim 6, wherein: The first-stage calcination atmosphere is air; and the second-stage calcination atmosphere is nitrogen.

8. The method of claim 6, wherein: The second-stage calcination temperature is 150-300℃ higher than the first-stage calcination temperature.

9. The method of claim 1, wherein: In step (3), the mass content of the high-molecular compound in the water emulsion is 5.0%-15.0%, and the mass content of the water-soluble cellulose is 0.5%-3.0%. And / or, in step (3), the water emulsion is used in an amount of 0.8-1.5mL / g based on the mass of the pre-supporting carrier.

10. The method of claim 1, wherein: In step (3), the calcination conditions are as follows: the temperature is 500-700℃, the time is 2.0-8.0h, and the calcination atmosphere is an inert atmosphere. And / or, in step (5), the calcination temperature is 550-750℃, the calcination time is 2-10h, and the volume ratio of air to water vapor in the mixed atmosphere is 0.1-5.0:1.

0.

11. The method of claim 10, wherein: The calcination atmosphere is one or more of nitrogen and argon.

12. The method of claim 1, wherein: In the second active metal, the Group VIII metal is Ni.

13. The method of claim 1, wherein: The second active metal impregnation solution contains at least one additive containing fluorine, phosphorus, silicon, or boron.

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

15. The method of claim 1, wherein: In the second active metal impregnation solution, the content of Mo as MoO3 is 10.0-50.0g / 100mL, and the content of the Group VIII metal as an oxide is 3.0-20.0g / 100mL. And / or, the mass of the Group VIII metal introduced into the catalyst from the second active metal impregnation solution as an oxide accounts for 50.0%-80.0% of the total Group VIII metal loading in the catalyst as an oxide. And / or, the content of the additive in the second active metal impregnation solution is 3.0-18.0g / 100mL. And / or, the content of the water-soluble high polymer J in the second active metal impregnation solution is 0.5-2.5g / 100mL.

16. The method of claim 15, wherein: The content of the additive in the second active metal impregnation solution is 5.0-15.0g / 100mL.

17. A residual oil hydrodemetallization catalyst prepared by the preparation method of any one of claims 1-16.

18. The catalyst of claim 17, wherein: In the catalyst, the content of MoO3 is 10.0%-28.0% based on the mass of the catalyst, and the content of the Group VIII metal oxide is 2.0%-20.0% based on the mass of the catalyst.

19. The catalyst of claim 18, wherein: In the catalyst, the mass ratio of the Group VIII metal introduced into the catalyst from the first active metal component as an oxide to the Group VIII metal introduced into the catalyst from the second active metal component as an oxide is 0.5-1.5:

1.

20. The catalyst of claim 18, wherein: In the catalyst, the content of the additive as an oxide is 1.0%-6.0% based on the mass of the catalyst.

21. The catalyst of claim 17, wherein: The specific surface area of the catalyst is 160 to 210 m 2 / g, and the pore volume is 0.50 to 0.90 mL / g.

22. The catalyst of claim 21, wherein: The specific surface area of the catalyst is 160 to 190 m 2 / g, and the pore volume is 0.60 to 0.80 mL / g.

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