CN119236912A - A catalyst for hydrodemetallization of low-quality residual oil and preparation method thereof - Google Patents

Abstract

The invention discloses a preparation method of a catalyst for hydrogenating and demetallizing low-quality residual oil, comprising: mixing hydrated alumina, phenolic resin and a binder, adding an aqueous solution containing low-carbon alcohol, kneading, molding, drying and calcining to obtain an alumina carrier; dissolving a metal compound by using an organic acid and hydrogen peroxide, adding a composite complexing agent, and preparing a metal impregnation solution; wherein the active metal compound includes metals of Group VIII and Group VIB; the specific surface area of the catalyst for hydrogenating and demetallizing low-quality residual oil is ^80-180m2 /g, the pore volume is ^0.5-1.1cm3 /g, and the proportion of the pore volume corresponding to the pores with a pore diameter greater than 100nm to the total pore volume is ≮10%. The invention uses phenolic resin as a pore-enlarging agent, partially dissolves under the action of low-carbon alcohol, and forms a macroporous diffusion channel with a diameter of more than 100nm in the alumina carrier after extension and cross-linking, has low cost, has both thermoplasticity and thermosetting properties, is easy to mold, and has high carrier strength.

Description

Poor-quality residual oil hydrodemetallization catalyst and preparation method thereof

Technical Field

The invention relates to a poor-quality residuum hydrodemetallization catalyst and a preparation method thereof, in particular to a residuum hydrodemetallization catalyst with a bimodal pore structure, good activity stability and high metal capacity and a preparation method thereof, which are suitable for the hydrotreatment process of heavy poor-quality residuum with high metal content.

Background

Currently, the world's oil refining industry is facing serious challenges in increasing the heaviness and inferior quality of crude oil resources. The residual oil accounts for 45-75% of the crude oil, and the property of the residual oil is obviously inferior to that of the fraction of gas oil with lower boiling range, so that the key of the deep processing of the crude oil to maximize the production of light products and chemical raw materials is the efficient conversion and utilization of the residual oil.

The residual oil hydrogenation is the most effective heavy and residual oil raw material processing technology, and most of impurities such as metal, sulfur, nitrogen and the like in the residual oil are removed through hydrogenation, so that the carbon residue value is reduced, and the further efficient processing and conversion are facilitated. The technical combination of residuum hydrotreatment and residuum catalytic cracking (RFCC) has become a key technical path for improving economic benefit for processing poor crude oil refining enterprises. The combination of the technology of the hydrotreatment of the residual oil and the catalytic cracking of the residual oil not only can maximally convert the residual oil which has low utilization value and is easy to cause environmental pollution and greatly improve the light oil yield, but also can obtain clean oil products with high added value and superior quality. In a certain sense, the crude oil is converted by 100 percent, and the wish of completely eating and squeezing the crude oil in the petroleum refining process is realized. The technology combination becomes a core technology for improving economic benefit of sulfur-containing crude oil refining enterprises.

The catalyst is the core of the residual oil hydrogenation technology and plays a decisive role in the stable and efficient operation of a residual oil hydrogenation device. The residual oil hydrotreating process is different from distillate oil hydrotreating, the running space velocity and the running period are far smaller than those of the distillate oil hydrotreating process, the catalyst loading is large, the deactivation is fast, and the statistical data show that about 40-50% of all types of hydrogenation catalysts are used in the residual oil hydrotreating process.

Residual oil is the heaviest and the worst component in petroleum, contains a large amount of colloid and asphaltene, has large molecular weight, large density, high viscosity, strong polarity and high content of sulfur and carbon residue, and enriches almost all metal impurities in petroleum. In the process of hydrotreating residual oil, the catalyst is permanently poisoned by metal such as Na, ca, ni, V in the residual oil deposited on the hydrogenation catalyst, and is a core factor to be considered in the heavy and poor residual oil hydrogenation process. Hydrodemetallization (HDM) catalysts are one of key technologies in heavy oil hydrotreating processes, and mainly serve to remove most of Ni, V and other metal impurities in raw materials, protect downstream desulfurization (HDS) and denitrification (HDN) catalysts, and have certain desulfurization capacity. The catalyst is required to have not only good metal removal capability but also higher metal impurity containing capability. Since most of the metal impurities in the residuum are present in colloid and asphaltene, the diffusion resistance is large. The demetallization agent is limited by the mass transfer and diffusion efficiency of the carrier, is easy to cause orifice blockage, has serious uneven deposition distribution of the removed impurities, and has limited metal holding capacity. All the above causes serious waste of the internal space of the catalyst, and the efficiency of the catalyst cannot be fully exerted. Therefore, the catalyst has larger pore volume, pore diameter and good pore channel permeability, so as to be beneficial to diffusion, reaction and deposition of macromolecular substances such as asphaltene and the like containing metal impurities in the residual oil raw material. One of the solutions is to use a carrier with a bimodal pore structure, wherein in the reaction process, macropores with pore diameters of more than 100nm provide channels for the diffusion of macromolecular reaction substances, so as to promote the diffusion and deposition of impurities to the internal pore channels of the catalyst, and pore channels with pore diameters of less than 50nm provide reaction surfaces and deposition places for the impurities. The two pore channels cooperate to enable the catalyst to have high demetallization activity and high impurity capacity.

On the other hand, the residual oil hydrotreating catalyst should have good hydrodeimpurity activity and operation stability is important. The activity stability of the residuum hydrotreating catalyst is closely related to the active phase structure thereof, and the active metal needs to be highly dispersed on the surface of the carrier. In general, the shorter the active metal platelet size, the fewer the number of layers, the better the dispersibility and the better the catalyst activity stability. Through developing a novel active metal solution system which is simple to operate, environment-friendly and excellent in stability, the interaction between a carrier and active metal is reduced, the dispersity of active metal of a residual oil hydrotreating catalyst is improved, the lengths and the number of platelet layers of MoS ₂ are reduced, and 1-2 layers of MoS ₂ wafers with more proportion are generated, so that the activity and the stability of the catalyst are improved, the processing adaptability of poor raw materials is improved during hydrogenation reaction, the running period is prolonged, and the running benefit is improved.

In the existing alumina carrier preparation technology, acidic substances such as nitric acid, acetic acid, aluminum nitrate and the like are mostly required to be added as peptizers during the molding of the alumina, and the addition of the acidic substances can damage the particle structure of the alumina, so that the pore volume and the pore diameter of the carrier are reduced. The organic binder is used for replacing peptizing acid to form the carrier, so that the pore volume and the pore diameter of the carrier can be increased to a certain extent, but the effect is limited. The existing method simply increases the pore-enlarging agent when increasing the macropore proportion of the carrier, and the problems of increased cost, difficult molding, reduced strength and the like are faced when preparing the carrier with the high macropore proportion and the catalyst with the bimodal pore structure.

In the preparation method of the residual oil hydrotreating catalyst, the traditional ammonia-containing alkaline metal impregnating solution system uses a large amount of ammonia water, so that the problem of environmental pollution is caused, and the ammonia gas overflows in a large amount in the production and preparation process, so that the odor is large and the environment is not friendly. In order to solve the problem of ammonia pollution, phosphoric acid and the like are adopted to prepare active metal impregnating solution in the prior art, but the catalyst prepared by the phosphoric acid has poor active metal dispersibility, and the catalyst has too high acidity due to too high phosphorus content, so that the catalyst is easy to coke and deactivate in the hydrotreating process, has insufficient stability and cannot meet the hydrotreating requirement of inferior heavy residual oil.

Disclosure of Invention

Aiming at the problems of poor pore structure, large pollution in the preparation process, environment unfriendly property, insufficient stability caused by poor dispersibility of active metal and the like of the existing residual oil hydrodemetallization catalyst, the invention provides the residual oil hydrodemetallization catalyst with a bimodal pore structure, large pore volume and pore diameter, excellent stability and green and environment-friendly preparation process and the preparation method by developing a novel carrier preparation and active metal loading method.

Aiming at the problems existing in the prior art, the invention provides a preparation method of a poor-quality residual oil hydrodemetallization catalyst, which uses phenolic resin as a pore-enlarging agent to prepare a macroporous alumina carrier with a bimodal pore structure, solves the problem of diffusion of a poor-quality residual oil macromolecular metal compound and asphaltene, and effectively reduces the emission of pollutants such as ammonia in the production process by developing an environment-friendly novel active metal solution system and a corresponding loading technology, so that the catalyst production is clean, and meanwhile, the active metal high-dispersion loading is realized to obtain the high-performance residual oil hydrodemetallization catalyst. The catalyst has an excellent bimodal pore structure, large pore volume and pore diameter, environment-friendly production process, no pollution and good state of high dispersion, low stacking and short platelet of active metal on the catalyst, and has excellent hydrogenation reaction performance when the catalyst is used in the residual oil hydrotreating process.

The basic technical scheme for solving the problems is as follows:

The preparation method of the catalyst for hydrodemetallization of the inferior residuum comprises the following steps:

(1) Mixing hydrated alumina, phenolic resin and adhesive, adding water solution containing low-carbon alcohol, kneading, forming, drying and roasting to obtain alumina carrier

(2) Dissolving a metal compound by using organic acid and hydrogen peroxide, adding a composite complexing agent to prepare a metal impregnating solution, impregnating the carrier in the step (1), and carrying out health maintenance, drying and roasting to obtain the catalyst.

The preferable technical scheme of the invention is as follows:

The hydrated alumina is selected from one or more of gibbsite, boehmite, pseudo-boehmite and amorphous aluminum hydroxide, preferably pseudo-boehmite. They may be commercially available or prepared by any of the methods known in the art, such as pseudo-boehmite prepared by the aluminum sulfate-sodium metaaluminate method;

the phenolic resin is polycondensate of phenol and formaldehyde, can be thermosetting or thermoplastic or a mixture of the thermosetting and the thermoplastic, has a particle size of 80-3000 meshes, preferably 120-2000 meshes, and is added in an amount of 2-25wt%, preferably 5-20wt%, calculated as aluminum oxide;

The adhesive is synthetic cellulose, is one or more selected from methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose and hydroxyethyl methyl cellulose, preferably hydroxypropyl methyl cellulose, and is added in an amount of 1-5wt% based on aluminum oxide;

The viscosity of the 2% mass concentration aqueous solution of the synthetic cellulose at 20 ℃ is not lower than 50000 mPa.s;

The low-carbon alcohol is selected from one or more of methanol, ethanol, glycol, propanol, isopropanol and glycerin, preferably methanol or ethanol, and the addition amount is 0.5-5wt% calculated by alumina;

The aqueous solution containing the lower alcohol has a temperature of 30-100 ℃, preferably 40-80 ℃;

The drying temperature of the alumina carrier is 100-180 ℃, preferably 120-160 ℃, the roasting temperature of the carrier is 500-1200 ℃, preferably 700-1000 ℃, and the roasting time is 1-4 hours;

the shape of the alumina carrier can be changed according to the need, including but not limited to a bar shape, a sphere shape, a Raschig ring, a tooth ball, a honeycomb shape, an impeller and the like, wherein the bar shape includes but not limited to a cylinder, clover, a butterfly shape and the like;

the alumina carrier can be added with various auxiliary agents according to the requirement, wherein the auxiliary agents comprise one or more of silicon, phosphorus, boron, titanium, zirconium, chlorine, fluorine and the like. The alumina carrier can be added with various molecular sieves according to the requirements, wherein the molecular sieves comprise one or more of X, Y, ZSM-5, beta, phosphorus aluminum, titanium silicon, ZSM-41, SBA-15 and the like;

The specific surface area of the alumina carrier is 80-240m ²/g, preferably 100-200m ²/g, the pore volume is 0.5-1.5cm ³/g, preferably 0.6-1.2cm ³/g, and the proportion of the pore volume corresponding to the pore channel with the pore diameter larger than 100nm to the total pore volume is less than 10%.

In the invention, the preparation steps of the metal impregnating solution in the step (2) are as follows:

(A) Mixing an active metal compound, organic acid, hydrogen peroxide and purified water to prepare an active metal aqueous solution;

(B) And (3) adding a composite complexing agent into the aqueous solution in the step (A) to obtain the active metal impregnating solution.

The active metal compound of step (a) comprises at least one metal selected from group VIII, preferably nickel and/or cobalt, most preferably nickel, and one metal selected from group VIB, preferably molybdenum and/or tungsten, most preferably molybdenum. The group VIII metal nickel is one or more of basic nickel carbonate, nickel sulfate, nickel nitrate, nickel acetate and nickel chloride, preferably nickel nitrate and nickel acetate. The group VIB metal molybdenum raw material is one or more of molybdenum trioxide, ammonium heptamolybdate (ammonium molybdate tetrahydrate), ammonium tetramolybdate, ammonium orthomolybdate, ammonium octamolybdate and ammonium dodecamolybdate, and is preferably molybdenum trioxide and ammonium heptamolybdate.

The organic acid in the step (A) at least comprises one or more of tartaric acid, oxalic acid, malic acid, citric acid, succinic acid and maleic acid, preferably oxalic acid, and the adding amount is 1.0-12.0g/100cm ³.

The hydrogen peroxide in the step (A) is added in an amount of 0.1-3.0g/100cm ³ calculated by H ₂O₂.

The specific preparation process of the active metal aqueous solution in the step (A) is as follows:

a) Mixing a group VIB metal raw material and an organic acid in a container, adding deionized water, heating at 60-100 ℃ and stirring to completely dissolve the raw material;

b) Adding a group VIII metal raw material into the solution obtained in the step a), stirring and dissolving, and heating appropriately if necessary to obtain an active metal mixture solution;

c) Adding hydrogen peroxide into the solution obtained in the step b) to obtain an active metal aqueous solution.

The compound complexing agent in the step (B) is a combination of a polycarboxylic acid scale inhibitor and an organic phosphorus-containing compound. The polycarboxylic acid scale inhibitor at least comprises one or more of polyepoxysuccinic acid, polyacrylic acid, hydrolyzed polymaleic anhydride, maleic acid-acrylic acid copolymer, polyaspartic acid, acrylic acid-hydroxypropyl acrylate copolymer (T-225) and acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, and the addition amount is 0.5-15.0g/100cm ³. The organic phosphorus-containing compound at least comprises one or more of amino trimethylene phosphonic acid, diethylene triamine pentamethylene phosphonic acid, hydroxy ethylene diphosphonic acid and ethylenediamine tetramethylene phosphonic acid, and the addition amount is 0.5-10.0g/100cm ³.

The impregnation method in the step (2) can be an equal-volume impregnation method, a supersaturation impregnation method and the like, the impregnation method can spray the solution on the surface of the carrier or submerge the carrier in the solution, the impregnation process can carry out vacuumizing treatment on the carrier or directly impregnate the carrier, the impregnation process can heat the carrier or carry out the impregnation under the normal temperature condition, and the impregnation process can adopt auxiliary technologies such as ultrasonic waves or microwaves.

In the step (2), the immersed sample is subjected to health care treatment under a closed condition at a temperature of 20-100 ℃, preferably 20-60 ℃ and a holding time of 0.5-6 hours, preferably 1.0-4 hours, and the drying condition is 80-180 ℃, preferably 100-140 ℃ and the drying time is 1-6 hours, preferably 2-4 hours.

In the step (2), the roasting temperature is 400-700 ℃, preferably 420-600 ℃, and the roasting time is 0.5-6 hours, preferably 1-4 hours.

The poor residuum hydrodemetallization catalyst comprises 2-12% of VIB metal and 0.4-3% of VIII metal based on the total weight of the catalyst, wherein the VIB metal accounts for the total weight of the catalyst.

The catalyst has a specific surface area of 80-180m ²/g, a pore volume of 0.5-1.1cm ³/g, and pore volume corresponding to pore channels with a pore diameter of more than 100nm accounts for less than 10% of the total pore volume.

The catalyst for hydrodemetallization of inferior residuum prepared by the method.

Compared with the prior art, the catalyst for hydrodemetallization of inferior residuum and the preparation method thereof have the following advantages:

(1) Phenolic resin is used as a pore-expanding agent, is partially dissolved under the action of low-carbon alcohol, and forms a macroporous diffusion channel of more than 100nm in an alumina carrier after extension and cross-linking, so that the preparation method has the advantages of low cost, thermoplasticity and thermosetting property, easy molding and high carrier strength.

(2) The metal solution system is prepared by using organic acid, wherein organic acid radical ions have coordination sites which can form coordination bonds with metal ions, and the organic acid radical ions can form stable complexes with the active metal ions through coordination with the active metal ions. The organic acid has weak acidity, so that the corrosion loss of the carrier can be reduced. The addition of hydrogen peroxide can generate oxidation-reduction reaction under acidic condition, promote the formation of relatively stable oxidation product of active metal, weaken the interaction of active component and alumina carrier, and can produce positive effect on the activity stability of final residuum hydrotreating catalyst. The preparation process of the metal impregnating solution does not use volatile ammonia, the solution system is environment-friendly, and the production process is environment-friendly.

(3) The complex complexing agent is adopted, so that the complex complexing agent has strong complexing capacity and good solution stability. Through efficient complexation, the length of a metal active phase wafer is shortened, the number of layers of the wafer is reduced, a 1-2-layer wafer structure with more proportion is generated, high-dispersion loading of active metal is realized, and the activity and stability of the catalyst are improved. The organic phosphorus-containing compound in the compound complexing agent is used for introducing a proper amount of phosphorus into an acidic active metal solution system, so that the strong interaction between an active component and a carrier can be effectively weakened, and the metal active phase structure is optimized, thereby improving the dispersion degree of active metal of the residual oil hydrotreating catalyst. Meanwhile, the problems of excessive phosphorus, over-strong acidity, aggregation of metal components and the like caused by preparing an acidic system of an active metal solution by using phosphoric acid are avoided, the increase of the number of sheets and the length of active phases of the catalyst is prevented, the stability reduction in the hydrogenation reaction process of the catalyst is avoided, and the processing adaptability of inferior residual oil is stronger.

Drawings

FIG. 1 is a TEM transmission electron micrograph of catalyst B of example 2.

FIG. 2 is a TEM transmission electron micrograph of catalyst D of example 4.

FIG. 3 is a TEM transmission electron micrograph of comparative example 1 catalyst G.

FIG. 4 is a graph of mercury intrusion pore size distribution of catalyst A of example 1.

Detailed Description

The present invention will be specifically described below by way of examples. It is noted herein that the following examples are given solely for the purpose of illustration and are not to be construed as limiting the scope of the invention, as many insubstantial modifications and variations of the invention will become apparent to those skilled in the art in light of the above disclosure.

Example 1:

500g of PN-2 type macroporous pseudo-boehmite dry powder (dry basis content is 71.5 wt%) produced by the Confucius polyinnovation materials limited company is weighed, 35.8g of phenolic resin powder with the granularity of 1000 meshes and 10.7g of hydroxypropyl methylcellulose with the viscosity of 15 ten thousand mPas (namely the viscosity of 2% aqueous solution at 20 ℃) are added, the mixture is uniformly mixed, 10g of ethanol is dissolved in 607.8g of purified water, heated to 60 ℃, slowly added into the materials, kneaded into a plastic body, extruded into clover shape with the diameter of 1.6mm on a single screw extruder, dried for 2.0 hours at 140 ℃, then placed into a high-temperature roasting furnace, and the temperature of 900 ℃ is kept constant for 3 hours, so that a carrier a is obtained, and the physical and chemical properties of the carrier a are shown in a table 1.

Respectively weighing 2.0g of molybdenum trioxide and 1.0g of oxalic acid, placing into a beaker, adding 60g of deionized water, heating and stirring at 95 ℃ to dissolve, weighing 2.08g of nickel nitrate, adding, stirring and dissolving, cooling the solution to room temperature, adding 0.5g of 20% hydrogen peroxide under stirring, adding 0.5g of polyacrylic acid and 0.5g of diethylenetriamine pentamethylene phosphonic acid, stirring and dissolving, and calibrating to 100cm ³ to obtain an active metal impregnating solution. Weighing 50g of carrier a, soaking the carrier a with the soaking liquid in an equal volume soaking method in a spraying mode, carrying out health preservation treatment on the soaked sample for 1 hour under a closed condition of 20 ℃, drying for 2 hours under a condition of 110 ℃, and roasting the dried sample at a constant temperature of 550 ℃ for 4 hours to obtain the residual oil hydrotreating catalyst A. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 2:

500g of PN-2 type macroporous pseudo-boehmite dry powder (dry basis content is 71.5 wt%) produced by the Confucius polyinnovation materials limited company is weighed, 71.5g of phenolic resin powder with the granularity of 120 meshes and 17.9g of hydroxypropyl methylcellulose with the viscosity of 5 ten thousand mPas (the viscosity of 2% mass concentration aqueous solution at 20 ℃) are added, the mixture is uniformly mixed, 17.9g of ethanol is dissolved in 607.8g of purified water, the mixture is heated to 80 ℃, slowly added into the materials, kneaded into a plastic body, then the plastic body is extruded into clover with the diameter of 1.6mm on a single screw extruder, the clover is dried at 160 ℃ for 1.0 hour, and then the mixture is put into a high-temperature roasting furnace for 4 hours at the constant temperature of 700 ℃ to obtain a carrier b, wherein the physical and chemical properties of the carrier b are shown in table 1.

7.68G of molybdenum trioxide and 4.0g of oxalic acid are weighed and placed in a beaker, 60g of deionized water is added, heating and stirring are carried out at 60 ℃ to dissolve the molybdenum trioxide and the oxalic acid, 5.54g of nickel nitrate is weighed and added, stirring is carried out to dissolve the nickel nitrate, the solution is cooled to room temperature, 6.0g of 20% hydrogen peroxide is added gradually under stirring, 4.0g of epoxy succinic acid and 3.0g of amino trimethylene phosphonic acid are added under stirring, stirring and dissolving are carried out at room temperature, and the solution is calibrated to 100cm ³. Weighing 50g of carrier B, soaking the above-mentioned soaking solution on the alumina carrier B by adopting an isovolumetric soaking method in a spraying mode, curing the soaked sample for 4 hours under the closed condition of 40 ℃, drying for 4 hours under the condition of 100 ℃, and roasting the dried sample for 2 hours under the constant temperature of 500 ℃ to obtain the residual oil hydrotreating catalyst B. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 3:

500g of PN-2 type macroporous pseudo-boehmite dry rubber powder (dry basis content is 71.5 wt%) produced by the Confucius polyinnovation materials limited company is weighed, 17.9g of phenolic resin powder with the granularity of 2000 meshes and 3.6g of hydroxypropyl methyl cellulose with the viscosity of 20 ten thousand mPa.s (the viscosity of 2% aqueous solution at 20 ℃) are added, the mixture is uniformly mixed, 1.8g of ethanol is dissolved in 607.8g of purified water, the mixture is heated to 40 ℃, slowly added into the materials, kneaded into a plastic body, then the plastic body is extruded into clover shape with the diameter of 1.6mm on a single screw extruder, the clover shape is dried for 3.0 hours at 120 ℃, the mixture is put into a high-temperature roasting furnace, the temperature of 1000 ℃ is kept for 1 hour, and the physical and chemical properties of the carrier C are shown in the table 1.

Weighing 11.53g of ammonium heptamolybdate and 6.0g of oxalic acid, placing into a beaker, adding 60g of deionized water, heating and stirring at 98 ℃ to dissolve, weighing 6.47g of nickel acetate, adding, stirring and dissolving, cooling the solution to room temperature, adding 7.5g of 20% hydrogen peroxide in a dropwise manner under stirring, adding 4.0g of hydrolyzed polymaleic anhydride and 10.0g of hydroxyethylidene diphosphonic acid under stirring, stirring and dissolving at normal temperature, and calibrating the solution to 100cm ³. Weighing 50g of carrier C, soaking the above-mentioned soaking solution on the alumina carrier C by adopting an isovolumetric soaking method in a spraying mode, curing the soaked sample for 2 hours under the closed condition of 45 ℃, drying for 2 hours under the condition of 120 ℃, and roasting the dried sample for 1 hour under the constant temperature of 600 ℃ to obtain the residual oil hydrotreating catalyst C. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 4:

Weighing 500g of pseudo-boehmite dry powder, adding 53.6g of phenolic resin powder with the granularity of 300 meshes, adding 10.7g of hydroxypropyl methylcellulose with the viscosity of 15 ten thousand mPa.s, uniformly mixing, dissolving 14.3g of methanol in 600.0g of purified water, heating to 50 ℃, slowly adding the mixture into the mixture, kneading the mixture into a plastic body, extruding the plastic body into clover with the diameter of 1.6mm on a single screw extruder, drying the plastic body at 130 ℃ for 3 hours, and then placing the plastic body into a high-temperature roasting furnace, wherein the physical and chemical properties of the carrier d are shown in a table 1, and keeping the temperature at 800 ℃ for 2 hours.

Weighing 11.81g of molybdenum trioxide and 8.0g of oxalic acid, placing into a beaker, adding 65g of deionized water, heating and stirring at 100 ℃ to dissolve, weighing 8.33g of nickel nitrate, stirring to dissolve, cooling the solution to room temperature, adding 9.0g of 20% hydrogen peroxide in a dropwise manner under stirring, adding 6.0g of hydrolyzed polymaleic anhydride and 4.0g of ethylenediamine tetramethylene phosphonic acid under stirring, stirring and dissolving at normal temperature, and calibrating the solution to 100cm ³. Weighing the carrier D50 g, soaking the soaking liquid on the alumina carrier D in a spraying mode by adopting an isovolumetric soaking method, carrying out health preserving treatment on the soaked sample under a 60 ℃ closed condition for 3 hours, drying the sample under a 140 ℃ condition for 2 hours, and roasting the dried sample under a 480 ℃ constant temperature for 2 hours to obtain the residual oil hydrotreating catalyst D. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 5:

Weighing 500g of pseudo-boehmite dry powder, adding 25.0g of phenolic resin powder with the granularity of 600 meshes, adding 10.7g of hydroxypropyl methylcellulose with the viscosity of 15 ten thousand mPa.s, uniformly mixing, dissolving 7.2g of ethanol and 7.2g of methanol in 603.0g of purified water, heating to 50 ℃, slowly adding the mixture into the materials, kneading into a plastic body, extruding the plastic body into clover with the diameter of 1.6mm on a single screw extruder, drying for 3 hours at 130 ℃, and then placing the mixture into a high-temperature roasting furnace, keeping the temperature at 950 ℃ for 3 hours to obtain a carrier e, wherein the physical and chemical properties of the carrier e are shown in a table 1.

Weighing 14.31g of molybdenum trioxide and 11.0g of oxalic acid, placing into a beaker, adding 65g of deionized water, heating and stirring at 85 ℃ to dissolve, weighing 8.73g of nickel nitrate, adding, stirring to dissolve, cooling the solution to room temperature, adding 12.0g of 20% hydrogen peroxide in a dropwise manner under stirring, adding 15.0g of polyacrylic acid and 6.0g of ethylenediamine tetramethylene phosphonic acid under stirring, stirring and dissolving at normal temperature, and calibrating the solution to 100cm ³. Weighing 50g of the carrier E, soaking the alumina carrier E with the soaking liquid in an equal volume soaking method in a spraying mode, carrying out health preservation treatment on the soaked sample for 4 hours under a 40 ℃ closed condition, drying for 3 hours under a 120 ℃ condition, and roasting the dried sample at a constant temperature of 460 ℃ for 3 hours to obtain the residual oil hydrotreating catalyst E. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 6:

Weighing 500g of pseudo-boehmite dry powder, adding 28.6g of phenolic resin powder with the granularity of 200 meshes, adding 10.7g of hydroxypropyl methylcellulose with the viscosity of 15 ten thousand mPa.s, uniformly mixing, dissolving 10.7g of ethanol in 600.0g of purified water, heating to 55 ℃, slowly adding the mixture into the mixture, kneading the mixture into a plastic body, extruding the plastic body into clover with the diameter of 1.6mm on a single screw extruder, drying the plastic body at 120 ℃ for 3 hours, and then placing the plastic body into a high-temperature roasting furnace, and keeping the temperature at 850 ℃ for 3 hours to obtain a carrier f, wherein the physical and chemical properties of the carrier f are shown in a table 1.

Weighing 18.0g of molybdenum trioxide and 12.0g of oxalic acid, placing into a beaker, adding 60g of deionized water, heating and stirring at 90 ℃ to dissolve, weighing 20.83g of nickel nitrate, adding, stirring to dissolve, cooling the solution to room temperature, adding 15.0g of 20% hydrogen peroxide in a dropwise manner under stirring, adding 8.0g of epoxy succinic acid and 5.0g of hydroxyethylidene diphosphonic acid under stirring, stirring and dissolving at normal temperature, and calibrating the solution to be 100cm ³. Weighing the carrier F50 g, soaking the soaking liquid on the alumina carrier F in a spraying mode by adopting an isovolumetric soaking method, carrying out health preserving treatment on the soaked sample for 2 hours under a 55 ℃ closed condition, drying for 3 hours under a 110 ℃ condition, and roasting the dried sample for 3 hours under a 420 ℃ constant temperature to obtain the residual oil hydrotreating catalyst F. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Comparative examples 1-3 illustrate prior art processes and residuum hydrotreating catalysts prepared by prior art processes.

Comparative example 1:

Comparative example 1 was an alumina support prepared by the method described with reference to CN105983443B, and the metal impregnation solution was formulated by the method provided with reference to CN114425354B, with the catalyst metal loading being the same as in example 2.

500G of macroporous pseudo-boehmite dry powder (dry basis content 71.5 wt%) produced by the tobacco stand Henghui chemical industry Co., ltd is weighed, 10.7g of hydroxypropyl methyl cellulose with the viscosity of 15 ten thousand mPa.s (the viscosity of 2% aqueous solution) and 17.9g of polyvinyl alcohol powder with the particle diameter of 90-150 mu m are added, evenly mixed, 14.3 g of boric acid is dissolved in 390g of purified water, slowly added into the materials, kneaded into a plastic body, and then extruded into clover with the diameter of 1.6mm on a front extrusion single screw extruder. Drying at 120deg.C for 2.0 hr, and placing into roasting furnace, and keeping at 800 deg.C for 3 hr to obtain carrier g, the physicochemical properties of which are shown in Table 1.

7.68G of molybdenum trioxide and 2.61g of basic nickel carbonate are weighed, placed in a beaker, added with water and stirred, 3.76g of phosphoric acid is weighed, diluted with water and then slowly added into the beaker for reaction at normal temperature for 15 minutes, the temperature is raised to 95 ℃ and heated for 35 minutes, 3.0g of citric acid is weighed and added, the constant temperature heating is continued for 25 minutes until all raw materials are dissolved, the heating is closed and cooled to room temperature, 10.0g of triethanolamine and 3g of tween-80 are added under stirring, and the mixture is calibrated to 100cm ³ for standby after stirring and dissolution. The impregnation liquid is impregnated on the carrier G by adopting a spraying mode, and the impregnated sample is dried and then kept at the constant temperature of 500 ℃ for 2 hours to obtain the catalyst G. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Comparative example 2:

comparative example 2 an alumina support was prepared as described with reference to CN1103009a, and the metal impregnation solution was formulated as disclosed with reference to CN103007949B, with the catalyst metal loading being the same as in example 2.

34.1G of aluminum hydroxide dry rubber powder (containing 75% of aluminum oxide alkyl aluminum hydrolysate) and 39.3g of aluminum hydroxide powder prepared by an aluminum sulfate method are mixed, 4.7g of high wear-resistant carbon black, 3.5g of surfactant SA-20 and 2.1g of aluminum nitrate and 66 ml of water are added, fully ground and mixed, extruded into a clover shape with the diameter of 1.8 mm on a strip extruder, dried at 120 ℃ and baked at 600 ℃ for 4 hours, and a carrier h is obtained, wherein the physicochemical properties are shown in table 1.

Adding 30% hydrogen peroxide dropwise into 9.48g ammonium heptamolybdate, stirring for dissolving, adding 5.54g nickel nitrate, stirring for dissolving, adding 1.5g terephthalic acid, and calibrating to 100cm ³. The solution was dropped onto the support H, immersed at room temperature for 6 hours, dried at 110℃for 2 hours, and calcined at 500℃for 4 hours to obtain catalyst H. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Comparative example 3:

Comparative example 3 an alumina support was prepared as described in patent CN1647857a, and the preparation of the metal impregnation solution was carried out as disclosed in patent CN1230491C, with the catalyst metal loading being the same as in example 2.

500G of PN-2 type macroporous pseudo-boehmite dry powder (aluminum sulfate-sodium metaaluminate method, dry basis content of 71.5 wt%) produced by the Lizhou polyinnovation materials are weighed, 10.7g of polyethylene glycol with molecular weight of 2000 is added, water is added for pulping, 6 liters of slurry is finally obtained, then spray drying is carried out at the inlet temperature of 580 ℃ and the outlet temperature of 180 ℃, the obtained composition is extruded and dried, and the carrier i is obtained after roasting for 3 hours at 800 ℃, wherein the physicochemical properties are shown in Table 1.

And (3) placing ammonia water with the concentration of 75cm ³ and 18 percent in an ultrasonic transducer, controlling the emission power to be 350W and the frequency to be 25kHz, adding 9.48g of ammonium heptamolybdate and dissolving the ammonium heptamolybdate, adding 5.54g of nickel nitrate, completely dissolving metal salt, closing the ultrasonic transducer, adjusting the volume of the solution to 100cm ³ by using ammonia water, dripping the solution onto a carrier I, soaking for 4 hours at room temperature, drying for 2 hours at 120 ℃, and roasting for 3 hours at 500 ℃ to obtain the catalyst I. The results of the active phase Transmission Electron Microscope (TEM) analysis after the catalyst was sulfided are shown in Table 2.

Example 7:

This example is an activity evaluation test of the catalysts obtained in examples 1 to 6 and comparative examples 1 to 3, for comparing hydrogenation reaction performance of catalysts prepared by different methods.

And performing performance tests on the catalyst B, the catalyst G, the catalyst H and the catalyst I by adopting the same raw oil and process conditions on a fixed bed residual oil hydrogenation evaluation device. The properties and process conditions of the raw oil are shown in Table 3, and the evaluation results are shown in Table 4.

From the above, it can be seen from examples 1 to 7 and comparative examples 1 to 3:

(1) As shown by the physical property data of the carrier in the table 1, compared with the prior art, the carrier obtained by the invention has the characteristics of large pore volume and aperture, high macropore proportion of more than 100nm and good strength, and can be better suitable for the hydrodemetallization process of inferior residual oil;

(2) As shown by TEM characterization results in Table 2, the residual oil hydrotreating catalyst obtained by the invention has few platelet layers, mainly comprises single-layer and double-layer MoS ₂, has short platelet length and good active phase dispersibility, and has obvious characteristics of high dispersion, low stacking and short platelet, thus being more suitable for hydrotreating heavy and inferior residual oil, and the catalyst obtained by the comparative example has high proportion of more than 3 layers of platelet structures, large platelet length and poor active component dispersibility;

(3) As can be seen from the evaluation results in Table 4, compared with the catalyst of the comparative example, the catalyst prepared by the invention has better desulfurization, carbon residue removal and demetallization activities, good activity stability, stronger processing adaptability of inferior raw materials, and is beneficial to prolonging the running period of the device and improving the economic benefit.

TABLE 1 physicochemical Properties of the vector

TABLE 2 TEM characterization results of catalysts

Table 3 evaluation of test raw oil and process conditions

Nature of raw oil	Middle eastern residuum
		Density (20 ℃ C.)/g.cm -3	0.9884
Sulfur content, w%	4.478
		Carbon residue value, w%	13.20
Metal (Ni+V), μg.g -1	79.44
		Process conditions
Reaction temperature, °c	380
		Hydrogen partial pressure, MPa	16.0
Volume space velocity, h -1	1.0
		Hydrogen/oil ratio, V/V	700

Table 4 results of catalyst evaluation

Claims (10)

1. A method for preparing a catalyst for hydrodemetallization of low-quality residual oil, characterized in that it comprises the following steps: (1) mixing hydrated alumina, phenolic resin and a binder, adding an aqueous solution containing a low-carbon alcohol, kneading, forming, drying and calcining to obtain an alumina carrier; (2) dissolving the metal compound by using an organic acid and hydrogen peroxide, adding a complex complexing agent, and preparing a metal impregnation solution; impregnating the carrier in step (1), curing, drying, and calcining to obtain a catalyst; The active metal compound comprises at least one metal selected from Group VIII and one metal selected from Group VIB, and the metal of Group VIB accounts for 2-12% of the total weight of the catalyst and the metal of Group VIII accounts for 0.4-3% of the total weight of the catalyst in terms of oxide; The low-quality residue oil hydrodemetallization catalyst has a specific surface area of 80-180 m ² /g, a pore volume of 0.5-1.1 cm ³ /g, and a pore volume corresponding to pores with a pore diameter greater than 100 nm that accounts for ≮10% of the total pore volume. 2. The preparation method according to claim 1, characterized in that the step of preparing the metal impregnation solution in step (2) comprises: (A) mixing an active metal compound, an organic acid, hydrogen peroxide and purified water to prepare an active metal aqueous solution; (B) adding a composite complexing agent to the aqueous solution of step (A) to obtain an active metal impregnation solution; The organic acid includes at least one or more of tartaric acid, oxalic acid, malic acid, citric acid, succinic acid, and maleic acid; The composite complexing agent is a combination of a polycarboxylic acid scale inhibitor and an organic phosphorus-containing compound; The polycarboxylic acid scale inhibitor includes at least one or more of polyepoxysuccinic acid, polyacrylic acid, hydrolyzed polymaleic anhydride, maleic acid-acrylic acid copolymer, polyaspartic acid, acrylic acid-hydroxypropyl acrylate copolymer, acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer; The organic phosphorus-containing compound includes at least one or more of aminotrimethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, hydroxyethylenediphosphonic acid, and ethylenediaminetetramethylenephosphonic acid. 3. The preparation method according to claim 2, characterized in that: The specific preparation process of the active metal aqueous solution in step (A) is as follows: (a) Mixing a Group VIB metal raw material and an organic acid in a container, adding deionized water, heating at 60-100° C. and stirring to completely dissolve the mixture; (b) adding a Group VIII metal raw material to the solution obtained in step (a), stirring and dissolving, and heating appropriately if necessary, to obtain an active metal mixture solution; (c) adding hydrogen peroxide to the solution obtained in step (b) to obtain an active metal aqueous solution. 4. The preparation method according to claim 1, characterized in that in the step (2): The impregnated samples are cured in a closed environment at a temperature of 20-100°C for 0.5-6 hours; The drying condition is 80-180°C and the drying time is 1-6 hours; The calcination temperature is 400-700° C., and the calcination time is 0.5-6 hours. 5. The preparation method according to claim 1, characterized in that: The hydrated aluminum oxide is selected from one or a mixture of gibbsite, boehmite, pseudo-boehmite and amorphous aluminum hydroxide. 6. The preparation method according to claim 1, characterized in that: The phenolic resin is a condensation product of phenol and formaldehyde, and can be thermosetting or thermoplastic or a mixture of the two, and has a particle size of 80-3000 meshes; the addition amount is 2-25wt% based on alumina. 7. The preparation method according to claim 1, characterized in that: The binder is synthetic cellulose, selected from one or more of methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose and hydroxyethyl methyl cellulose, and the addition amount is 1-5wt% based on aluminum oxide; The viscosity of a 2% mass concentration aqueous solution of the synthetic cellulose at 20° C. is not less than 50,000 mPa·s. 8. The preparation method according to claim 1, characterized in that: The low-carbon alcohol is selected from one or more of methanol, ethanol, ethylene glycol, propanol, isopropanol and glycerol, and the added amount is 0.5-5wt% based on alumina; The temperature of the aqueous solution containing low-carbon alcohol is 30-100°C. 9. The preparation method according to claim 1, characterized in that: The drying temperature of the alumina carrier is 100-180°C; the calcination temperature of the alumina carrier is 500-1200°C, and the calcination time is 1-4 hours; The shape of the alumina carrier includes any one of a bar, a sphere, a Raschig ring, a toothed ball, a honeycomb, and an impeller; The auxiliary agent includes one or more of silicon, phosphorus, boron, titanium, zirconium, chlorine and fluorine; The molecular sieve added to the alumina carrier includes one or more of X, Y, ZSM-5, β, phosphorus aluminum, titanium silicon, ZSM-41, and SBA-15; The specific surface area of the alumina carrier is 80-240 m ² /g, the pore volume is 0.5-1.5 cm ³ /g, and the proportion of the pore volume corresponding to the pores with a pore diameter greater than 100 nm to the total pore volume is ≮10%. 10. A low-quality residue oil hydrodemetallization catalyst prepared according to the method for preparing a low-quality residue oil hydrodemetallization catalyst according to any one of claims 1 to 9.