A light oil product ultra-deep desulfurization refining catalyst, a preparation method and application thereof

Abstract

The application discloses a light oil super-deep desulfurization catalyst, a preparation method and application thereof. The catalyst comprises nanometer microcrystal composite metal oxide and zero-valence metal active components; the nanometer microcrystal composite metal oxide comprises aluminum oxide, silicon dioxide, titanium dioxide, magnesium oxide, calcium oxide, molybdenum trioxide, rare earth element oxide, nickel oxide and copper oxide; and the zero-valence metal active components comprise elemental nickel and copper. The desulfurizer has excellent desulfurization performance, good arsenic and chlorine removal performance, good catalyst stability and long service life.

Description

Technical Field

[0001] This invention relates to the field of desulfurization and refining catalysts, and particularly to a catalyst for ultra-deep desulfurization and refining of light oil products, its preparation method, and its application. Background Technology

[0002] Catalytic reforming is one of the important production processes in oil refining and petrochemicals. It refers to the process in which light gasoline fractions (or naphtha) obtained from crude oil distillation are converted into high-octane gasoline (reformed gasoline) rich in aromatics under the action of a catalyst, and liquefied petroleum gas and hydrogen are produced as byproducts.

[0003] Early catalytic reforming used single-platinum catalysts. Later, to improve aromatic yield, gasoline octane number, hydrogen production, and extend operating cycles, a series of highly efficient bimetallic reforming catalysts were developed. These catalysts, in addition to platinum, also incorporate rhenium, iridium, or tin as co-catalysts. Trace amounts of hydrogen sulfide, small amounts of organic sulfur, and arsenic and chlorine impurities in reforming feedstocks can adversely affect reforming catalysts. If these components are not removed, they can corrode equipment and pipelines, and even lead to catalyst poisoning or deactivation. The stringent requirements for sulfur content and arsenic and chlorine impurity content in reforming feedstocks have spurred the development of desulfurization and refining technologies for feedstocks.

[0004] There are many methods for oil desulfurization. Traditional and mature methods include hydrodesulfurization (HDS). However, to achieve ultra-deep desulfurization, the hydrogenation reaction must be carried out under high temperature and pressure, accompanied by the use of highly active catalysts. This results in high investment and operating costs for the equipment, and also leads to a significant decrease in octane number. Therefore, many scholars have researched non-hydrodesulfurization methods such as adsorption desulfurization, oxidative desulfurization, and extraction desulfurization, which are convenient to operate and have lower costs. Among these, adsorption desulfurization technology has become a research hotspot both domestically and internationally. Compared with other methods, adsorption desulfurization technology has mild operating conditions, low investment and operating costs, good desulfurization effect, and less environmental pollution. Furthermore, it does not reduce the effective components in the oil and has no impact on the octane number. The active components of adsorption desulfurizing agents are mostly one or more oxides of zinc, nickel, molybdenum, manganese, and iron metals, using oxides of Al, Si, Ti, and Zr, molecular sieves, activated carbon, or clay as carriers. Currently, the most commonly used desulfurizing agents for reforming feedstocks mainly use nickel, nickel-molybdenum-platinum, or nickel-zinc as active components, and silica or alumina as carriers, to reduce the sulfur content in the feedstock to about 0.5 ppm. However, these catalysts are mostly prepared by directly mixing metal oxides, which has disadvantages such as low radial crushing strength, narrow operating temperature range, poor stability, and short lifespan. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a catalyst for ultra-deep desulfurization and refining of light oil products, its preparation method, and its application. This invention prepares a nanocrystalline composite metal oxide precursor via an external field-assisted multi-metal homogeneous precipitation method. The precursor is then mixed with a molding aid and kneaded before reduction passivation to obtain a high-performance desulfurization and refining catalyst in which high-valence and zero-valence metal elements coexist synergistically. This catalyst has widely available raw materials, a simple preparation process, and low production costs.

[0006] In a first aspect, the present invention provides a catalyst for ultra-deep desulfurization and refining of light oil products, which is achieved by the following technical solution.

[0007] A catalyst for ultra-deep desulfurization and refining of light oil products includes nanocrystalline composite metal oxides and zero-valent metal active components; the nanocrystalline composite metal oxides include aluminum oxide, silicon dioxide, titanium dioxide, magnesium oxide, calcium oxide, molybdenum trioxide, rare earth element oxides, nickel oxide, and copper oxide; the zero-valent metal active components include elemental nickel and copper.

[0008] Furthermore, a catalyst for ultra-deep desulfurization and refining of light oil products comprises the following components by mass percentage: 35-45% aluminum oxide, 4.0-15.0% silicon dioxide, 0.1-2.0% titanium dioxide, 0.5-2.5% magnesium oxide, 0.5-2.0% calcium oxide, 0.1-0.5% molybdenum trioxide, 10.0-25.0% nickel oxide, 9.0-24.0% copper oxide, 3.0-15.0% zero-valent nickel, 4.0-16.0% zero-valent copper, and 0.1-0.5% rare earth element oxides.

[0009] Furthermore, the rare earth element is selected from at least one of lanthanum, cerium, and praseodymium.

[0010] Secondly, the present invention provides a method for preparing a catalyst for ultra-deep desulfurization and refining of light oil products, which is achieved by the following technical solution.

[0011] A method for preparing the above-mentioned ultra-deep desulfurization and refining catalyst for light oil products includes the following steps: S1. Preparation of nanocrystalline composite metal oxide precursors by external field-assisted homogeneous precipitation of multimetals; S2. After evaporating some of the water from the nanocrystalline composite metal oxide precursor, add appropriate amounts of binder, lubricant, molding aid, and molding coupling agent, knead into a ball, mature, extrude granulation or press into tablets, and dry and calcine to obtain the catalyst precursor. S3. The catalyst precursor is reduced and passivated to obtain the finished catalyst.

[0012] Specifically, a method for preparing a catalyst for ultra-deep desulfurization and refining of light oil products includes the following steps: S1. Preparation of nanocrystalline composite metal oxide precursors Solution I is prepared by dissolving nickel salt, copper salt, aluminum salt, molybdate, magnesium salt, calcium salt, and rare earth element salt; Solution II is prepared by preparing an alkaline precipitant and silicate; and a reaction base solution is prepared by preparing a dispersant and water. The reaction base solution is heated to 40-65°C, and then Solutions I and II are added to the reaction base solution under high-speed stirring. After reacting for a period of time, the external field auxiliary system is turned on, and the reactants are heated to 70-140°C and the pH is controlled at 6.5-9.0. The reaction solution is aged for 3.0-24.0 hours. The slurry is filtered, washed, and dried to a dry basis content of 60-90% to obtain the nanocrystalline composite metal oxide precursor. S2. Catalyst precursor preparation Lubricant, binder, molding aid and molding coupling agent are added to the nanocrystalline composite metal oxide precursor, kneaded into agglomerates, and then allowed to stand and mature at 30~40℃ for 2.0~24h. The precursor is then extruded into granules or pressed into tablets. The shaped catalyst is dried and calcined to obtain the catalyst precursor. S3. Catalyst reduction passivation The catalyst precursor is subjected to a reduction reaction under conditions of 400~600℃ by passing a mixture of N2 and H2 gas; then a passivation reaction is carried out by passing a mixture of O2, CO2 and N2 or a mixture of O2 and Ar gas. After the reaction is completed, the catalyst product is obtained.

[0013] Furthermore, in step S1, solution I is an aqueous solution containing nickel salt, copper salt, aluminum salt, molybdate, magnesium salt, calcium salt, and rare earth element salts.

[0014] Furthermore, in step S1, the metal salt is selected from metal nitrates, sulfates, oxalates, chlorides, or carbonates, and the molybdate is selected from ammonium molybdate or sodium molybdate.

[0015] Furthermore, in step S1, the alkaline precipitant is selected from urea, hexamethylenetetramine, and at least one of sodium carbonate, sodium hydroxide, ammonia, and triethanolamine. The amount of alkaline precipitant used is 1.0 to 1.5 times the total number of moles of metal salts in solution I.

[0016] Furthermore, in step S1, solution II is an aqueous solution containing an alkaline precipitant and silicates.

[0017] Furthermore, in step S1, polyethylene glycol is selected as the dispersant, and the amount of dispersant used is 0.1~1.0% of the mass of the final catalyst.

[0018] Furthermore, in step S1, after adding solution I and solution II to the reaction substrate, the pH of the system is controlled at 4.0~6.0, and the reaction is carried out for 0.5~3.0 hours.

[0019] Furthermore, in step S1, the external field auxiliary system is selected from at least one of magnetic field, electric field, ultrasonic field, and microwave field.

[0020] Furthermore, in step S2, the lubricant is selected from at least one of methylcellulose, guar gum powder, and graphite, and the amount of lubricant used is 3-8.0% of the mass of the nanocrystalline composite metal oxide precursor; the binder is selected from silica sol or dilute acid, the silica sol has a silicon oxide content of 30-40%, and the amount of silica sol used is 17-20% of the mass of the nanocrystalline composite metal oxide precursor; the dilute acid is selected from one or more of nitric acid, citric acid, acetic acid, and propionic acid, and the concentration of the acid is controlled at 0.5-10.0%, preferably 3.0-8.0%, and the amount of dilute acid used is 2.0-7.5% of the mass of the nanocrystalline composite metal oxide precursor; the molding aid is selected from at least one of starch, glucose, and chitosan, and the amount used is 5-7% of the mass of the nanocrystalline composite metal oxide precursor; the molding coupling agent is selected from organic titanate.

[0021] Furthermore, in step S2, knead for 20-60 minutes until a dough forms.

[0022] Furthermore, in step S3, the reduction reaction time is 2 to 72 hours.

[0023] Furthermore, in step S3, the passivation process uses a mixture of O2, CO2, and N2 or a mixture of O2 and Ar, with the oxygen content in the mixture controlled at 0.1~10.0%, preferably 0.1~2.0%; the temperature controlled at 30~60℃, the bed temperature rise controlled below 30℃, the pressure controlled at 0.2~1.0MPa, preferably 0.4~0.6MPa; and the reaction time is 12~72 hours, preferably 24~36 hours.

[0024] Thirdly, the present invention provides the use of a catalyst for ultra-deep desulfurization and refining of light oil products, which is achieved by the following technical solution.

[0025] Application of the above-mentioned catalyst in the ultra-deep desulfurization reaction of light oil products.

[0026] This application has the following beneficial effects.

[0027] 1. This invention uses an external field-assisted multi-metal homogeneous precipitation method to prepare nanocrystalline composite metal oxide precursors. The precursor grain size is controllable and the particle size distribution is concentrated. The particle size of the metal oxide precursor is D90=8~20μm. The catalyst active components obtained by subsequent processes are uniformly dispersed and have small particle size. During the reaction process, more active sites can be exposed to contact with the reactants, resulting in high catalyst activity. 2. The molding and kneading process adds a curing process compared to the traditional molding process, which allows the lubricant, binder, molding aid, and molding coupling agent to react fully, effectively improving the strength of the high metal content catalyst after molding, reducing wear during catalyst use, reducing loss of active components, and extending the service life of the catalyst. 3. By adjusting the reduction and passivation processes, the high-valence and zero-valence states of metal elements in the catalyst can coexist synergistically, effectively improving catalyst stability, reducing sintering during use, and extending catalyst lifespan. This facilitates transportation and storage after industrial production, preventing spontaneous combustion or oxidation deactivation of the catalyst upon contact with air. The catalyst does not require hydrogen activation during use; after loading, it can be put into operation after a simple purging, saving start-up time and reducing energy consumption. 4. The catalyst prepared by the method of this invention has a wider operating temperature range, and the total sulfur content is 100 μg·g⁻¹ under higher space velocities. -1 Arsenic content: 0.1 μg·g -1 Chlorine content 100 μg·g -1 After processing, the sulfur, arsenic, and chlorine impurities in the feedstock oil can be reduced to 0.1 μg·g⁻¹. -1 1ng·g -1 and 0.5 μg·g -1 It is capable of stable operation for long periods of time, with strong processing power and excellent performance. 5. The catalyst precursor of this invention utilizes external field-assisted homogeneous precipitation of multiple metals, enabling the one-step addition of various active components and additives, avoiding the cumbersome processes of stepwise impregnation or precipitation. The molding process only requires evaporating a portion of the moisture in the precursor before direct mixing and molding, eliminating the drying and calcination steps, reducing energy consumption, and simplifying the process flow. The entire catalyst production process is safe and easy to operate, requires minimal investment in production equipment, and has low catalyst production costs, making it suitable for large-scale industrial production. Attached Figure Description

[0028] Figure 1 Particle size distribution diagram of the metal oxide precursor for ultra-deep desulfurization and refining catalyst prepared in Example 3 of this invention; Figure 2 XRD characteristic spectrum of the ultra-deep desulfurization and refining catalyst prepared in Example 3 of this invention; Figure 3 Figure 1 shows the experimental results of the desulfurization reaction life of the ultra-deep desulfurization refining catalyst prepared in Example 3 of this invention and the commercially available desulfurization catalyst. Detailed Implementation

[0029] The present patent application will be further described below with reference to the embodiments.

[0030] Unless otherwise specified, the experimental methods used in the following preparation examples and embodiments are conventional methods; the materials and reagents used in the following preparation examples and embodiments are commercially available unless otherwise specified.

[0031] Example 1

[0032] A method for preparing a catalyst for ultra-deep desulfurization and refining of light oil products includes the following steps: 1) Preparation of catalyst precursor Combine 294.22gAl(NO3)3 •9H2O, 16.03gMg(NO3)2 • 6H2O, 4.86Ca(NO3)2 • 4H2O, 4.5g(NH4)6Mo7O 24 97.33g Ni(NO3)2 •6H2O, 67.70g Cu(NO3)2 •3H2O, and 0.54g La(NO3)3 •6H2O were dissolved in deionized water to prepare 1500mL solution I. 166.4g Na2CO3, 188.60g urea, and 65.40g NaSiO2 •9H2O were dissolved in deionized water to prepare 1500mL solution II. 4.0g triethanolamine was added to the reactor to prepare 500mL of reaction base solution. The reaction base solution was heated to 60℃, and stirring was started. Solutions I and II were added to the reactor in a parallel flow for 1.0 hour. The reactor temperature was then raised to 120℃, and the ultrasonic system was turned on at 60W to begin precipitation. The reaction lasted for 12.0 hours. After centrifugation, the slurry was separated and then washed and separated three times. The filter cake was dried to a dry basis content of 90% to obtain the metal oxide precursor.

[0033] 2) Catalyst precursor mixing and molding The above-mentioned metal oxide precursor was mixed with 4.0 g of carboxymethyl cellulose, 4.0 g of graphite powder, 20 mL of 3% citric acid, 80 mL of 3% propionic acid, 10 g of starch, and 20 g of organic titanate as a molding coupling agent. The mixture was kneaded for 20 minutes to form a pellet, and then allowed to stand at 30°C for 12 hours to mature. After maturation, the mixed raw materials were extruded and granulated into pentagonal toothed spherical particles with a diameter of Φ2.0 mm. After molding, the pellets were dried at 110°C and calcined at 600°C for 4 hours to obtain the catalyst precursor.

[0034] 3) Catalyst reduction passivation The calcined catalyst precursor was loaded into a reduction and passivation device and reduced at 350°C by a mixture of N2 and H2 (N2:H2 volume ratio 3:1). After 4 hours, the temperature was slowly lowered to 30°C. Then, a mixture of oxygen, carbon dioxide, and nitrogen was introduced to passivate the catalyst. The oxygen mass percentage was controlled at 2%, the temperature at 30°C, the bed temperature rise below 30°C, and the pressure at 0.6 MPa. After 36 hours of passivation, the oxygen mass percentage was slowly increased to 10% until no temperature rise occurred, indicating that passivation was complete.

[0035] After passivation, the material is unloaded, sealed, and stored to obtain a catalyst for ultra-deep desulfurization and refining of light oil products.

[0036] Example 2

[0037] In the metal oxide precursor preparation process of Example 1, the amount of Mg(NO3)2 • 6H2O added to solution I was increased to 32.06g and Ca(NO3)2 • 4H2O added to 9.72g; in solution II, the amount of NaSiO2 • 9H2O added was increased to 85.26g.

[0038] During the mixing and molding process of the catalyst precursor, the concentration of citric acid was increased to 5%, and 20 mL of 5% nitric acid was added simultaneously. The aging time was extended to 24 h. After aging, the mixed raw materials were extruded and granulated into pentagonal toothed spherical particles with a diameter of Φ2.5 mm. After molding, the particles were dried at 110 °C and calcined at 600 °C for 4 hours to obtain the catalyst precursor.

[0039] During the catalyst reduction passivation process, the reduction temperature was increased to 400℃ and the reduction time was extended to 6 hours.

[0040] Example 3

[0041] In the preparation process of the catalyst precursor in Example 1, Ni(NO3)2•6H2O in solution I was increased to 105.2 g, and the rare earth element addition was changed to 1.86 g Ce(NO3)3•6H2O. After the precipitation reaction, the crystallization process was initiated by raising the reactor temperature to 140°C and continuing to stir the reaction solution for 24.0 hours to complete the crystallization.

[0042] During the catalyst precursor mixing and molding process, 4.0g of carboxymethyl cellulose and 6.0g of guar gum powder were added, the citric acid concentration was increased to 5%, 30mL of 6% nitric acid was added, the amount of organic titanate added was reduced to 10g, the curing time was extended to 36h, and other conditions were the same as in Example 2.

[0043] During the catalyst reduction and passivation process, a mixture of N2 and H2 gas was passed through at 450℃ for 6.0 h for reduction.

[0044] Comparative Example A commercially available nickel-copper based desulfurization catalyst has the following composition: nickel oxide content 25.3% wt, copper oxide content 21.2% wt, and the content of the main active component is comparable to that in Example 3.

[0045] Performance testing 1. Performance evaluation tests of the catalyst were conducted in a fixed-bed reactor. Take 40 mL of the catalyst from Examples 1-3 and the comparative example, and pack it into the central isothermal zone of a fixed-bed reactor with dimensions of Φ40 mm × 600 mm (diameter × length). Then, fill both ends of the reactor with inert ceramic balls of Φ3 mm and Φ6 mm. After the catalyst is packed, purge with nitrogen gas at a flow rate of 10 L / h at room temperature for 2 h. Then, raise the temperature to the required reaction temperature at a rate of 20 °C / h, and adjust the process parameters according to the reaction requirements to evaluate the catalyst.

[0046] 1) Experimental raw materials: Heavy naphtha raw material was prepared and mixed with a certain amount of hydrogen sulfide, methanethiol, methyl ethyl sulfide, arsenic-containing compounds, and chlorine-containing compounds. The raw material composition was 50.0 μg / g hydrogen sulfide. -1 35.0 μg·g of methanethiol -1 15.0 μg·g of methyl ethyl sulfide -1 The total sulfur content is 100 μg·g -1 Arsenic content: 0.1 μg·g -1 ; Chlorine content 100 μg·g -1 .

[0047] 2) Evaluation of process conditions: After stabilizing at 100℃~180℃ and 0.15MPa~0.25MPa for 48 hours, product samples were collected for sulfur, chlorine, and arsenic content analysis. The total sulfur content at the reactor outlet was compared after 168 hours with different catalysts. Continuous operation was continued until the sulfur content at the reactor outlet reached 0.5 μg·g⁻¹. -1 If the catalyst is considered to have broken through, the reaction is stopped, the used catalyst is removed, and its sulfur capacity is analyzed.

[0048] The catalyst compressive strength was determined according to HG / T 2782. The total sulfur content of the raw materials and products was analyzed using a sulfur-nitrogen analyzer; sulfur type analysis was performed using an Agilent liquid chromatography sulfur analyzer, and the sulfur capacity detection method followed industry standard HG / T 2513; chlorine content was determined using a microcoulometric chlorine analyzer; arsenic content was determined using atomic fluorescence spectrometry, following standard GB / T 7686. The reaction results are shown in Table 1.

[0049] Process conditions 1: reaction temperature 100℃, reaction pressure 0.15 MPa, liquid hourly space velocity 6.0 h⁻¹ -1 .

[0050] Process conditions 2: Increase the reaction temperature to 120℃, the reaction pressure to 0.20 MPa, and the liquid hourly space velocity to 8.0 h⁻¹. -1 .

[0051] Process condition 3: Increase the reaction temperature to 140℃, adjust the reaction pressure to 0.25 MPa, and set the liquid hourly space velocity to 10.0 h⁻¹. -1 .

[0052] Process condition 4: Increase the reaction temperature to 180℃, adjust the reaction pressure to 0.25MPa, and increase the liquid hourly space velocity to 16.0 h⁻¹. -1 .

[0053] Table 1 Evaluation results of catalyst desulfurization, dechlorination, and arsenic removal performance

[0054] As can be seen from the performance evaluation results in Table 1, the catalyst prepared in this invention has higher strength and is more suitable for industrial applications. Under conditions of higher reaction temperature, higher space velocity, and higher pressure, the catalyst still exhibits strong removal capabilities for sulfides such as hydrogen sulfide, thiols, and thioethers, except for a slight decrease in sulfur capacity, and the total sulfur at the outlet can reach 0.1 μg·g⁻¹. -1 The following values ​​far exceed the total sulfur content of heavy naphtha exports, which should be <0.5 μg·g. -1 The catalyst exhibits superior performance in terms of arsenic and chlorine removal compared to commercially available comparative catalysts. Therefore, the catalyst prepared in this invention demonstrates technical advantages such as high space velocity, high activity, and high performance, and has significant potential for widespread application.

[0055] 2. Catalyst lifetime assessment experiment Appropriate amounts of the catalyst prepared in Example 3 and the commercially available nickel-copper-based desulfurization catalyst from the comparative example were respectively loaded into a fixed-bed reactor. The catalyst performance was evaluated under relatively stringent reaction conditions 4, and the reactor was run for over 1000 hours, with samples taken for analysis every 12 hours. The results are shown below. Figure 3 .

[0056] The total sulfur content at the reactor outlet of commercially available nickel-copper based desulfurization catalysts gradually increased, while the desulfurization rate gradually decreased to 99.2%. The catalyst prepared in Example 3, after a lifespan test of over 1000 hours, still maintained a total sulfur content of 0.1 μg·g at the reactor outlet. -1 The total sulfur removal rate remains above 99.9%, indicating stable catalyst performance.

[0057] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A catalyst for ultra-deep desulfurization and refining of light oil products, characterized in that: It includes nanocrystalline composite metal oxides and zero-valent metal active components; the nanocrystalline composite metal oxides include aluminum oxide, silicon dioxide, titanium dioxide, magnesium oxide, calcium oxide, molybdenum trioxide, rare earth element oxides, nickel oxide, and copper oxide; the zero-valent metal active components include elemental nickel and copper.

2. The catalyst for ultra-deep desulfurization and refining of light oil products according to claim 1, characterized in that: It comprises the following components by mass percentage: 35-45% aluminum oxide, 4.0-15.0% silicon dioxide, 0.1-2.0% titanium dioxide, 0.5-2.5% magnesium oxide, 0.5-2.0% calcium oxide, 0.1-0.5% molybdenum trioxide, 10.0-25.0% nickel oxide, 9.0-24.0% copper oxide, 3.0-15.0% zero-valent nickel, 4.0-16.0% zero-valent copper, and 0.1-0.5% rare earth element oxides.

3. The catalyst for ultra-deep desulfurization and refining of light oil products according to claim 1 or 2, characterized in that: The rare earth element is selected from at least one of lanthanum, cerium, and praseodymium.

4. A method for preparing the ultra-deep desulfurization and refining catalyst for light oil products according to any one of claims 1-3, characterized in that: Includes the following steps: S1. Preparation of nanocrystalline composite metal oxide precursors by external field-assisted homogeneous precipitation of multimetals; the external field is selected from at least one of magnetic field, electric field, ultrasonic field, and microwave field; S2. After evaporating some of the water from the nanocrystalline composite metal oxide precursor, add appropriate amounts of binder, lubricant, molding aid, and molding coupling agent, knead into a ball, mature, extrude granulation or press into tablets, and dry and calcine to obtain the catalyst precursor. S3. The catalyst precursor is reduced and passivated to obtain the finished catalyst.

5. The preparation method of a catalyst for ultra-deep desulfurization and refining of light oil products according to claim 4, characterized in that: Includes the following steps: S1. Preparation of nanocrystalline composite metal oxide precursors Solution I is prepared by dissolving nickel salt, copper salt, aluminum salt, molybdate, magnesium salt, calcium salt, and rare earth element salt; Solution II is prepared by preparing an alkaline precipitant and silicate; and a reaction base solution is prepared by preparing a dispersant and water. The reaction base solution is heated to 40-65°C, and then Solutions I and II are added to the reaction base solution under high-speed stirring. After reacting for a period of time, the external field auxiliary system is turned on, and the reactants are heated to 70-140°C and the pH is controlled at 6.5-9.

0. The reaction solution is aged for 3.0-24.0 hours. The slurry is filtered, washed, and dried to a dry basis content of 60-90% to obtain the nanocrystalline composite metal oxide precursor. S2. Catalyst precursor preparation Lubricant, binder, molding aid and molding coupling agent are added to the nanocrystalline composite metal oxide precursor, kneaded into agglomerate, and then allowed to stand and mature at 30~40℃ for 2.0~24h. The precursor is then extruded and granulated or pressed into tablets. The shaped catalyst is dried and calcined to obtain the catalyst precursor. The molding coupling agent is an organic titanate. S3. Catalyst reduction passivation The catalyst precursor is subjected to a reduction reaction under conditions of 400~600℃ by passing a mixture of N2 and H2 gas; then a passivation reaction is carried out by passing a mixture of O2, CO2 and N2 or a mixture of O2 and Ar gas. After the reaction is completed, the catalyst product is obtained.

6. The preparation method of a catalyst for ultra-deep desulfurization and refining of light oil products according to claim 5, characterized in that: In step S1, the alkaline precipitant is selected from urea, hexamethylenetetramine, and at least one of sodium carbonate, sodium hydroxide, ammonia, and triethanolamine. The amount of alkaline precipitant used is 1.0 to 1.5 times the total number of moles of metal salts in solution I.

7. The preparation method of a catalyst for ultra-deep desulfurization and refining of light oil products according to claim 5, characterized in that: In step S2, the lubricant is selected from at least one of methylcellulose, guar gum powder, and graphite, and the amount of lubricant used is 3-8.0% of the mass of the nanocrystalline composite metal oxide precursor; the binder is selected from silica sol or dilute acid, the silica sol has a silicon oxide content of 30-40%, and the amount of silica sol used is 17-20% of the mass of the nanocrystalline composite metal oxide precursor; the dilute acid is selected from one or more of nitric acid, citric acid, acetic acid, and propionic acid, the concentration of acid is controlled at 0.5-10.0%, and the amount of dilute acid used is 2.0-7.5% of the mass of the nanocrystalline composite metal oxide precursor; the molding aid is selected from at least one of starch, glucose, and chitosan, and the amount used is 5-7% of the mass of the nanocrystalline composite metal oxide precursor.

8. The preparation method of a catalyst for ultra-deep desulfurization and refining of light oil products according to claim 5, characterized in that: In step S3, the passivation process uses a mixture of O2, CO2, and N2 or a mixture of O2 and Ar. The oxygen content in the mixture is controlled at 0.1-10.0%, the temperature is controlled at 30-60℃, the bed temperature rise is controlled below 30℃, the pressure is controlled at 0.2-1.0MPa, and the reaction time is 12-72 hours.

9. The application of any one of the catalysts described in claims 1-3 in the ultra-deep desulfurization reaction of light oil products.

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