Preparation method of catalyst with hydrodesulfurization, denitrification and aromatic hydrocarbon saturation performance

Abstract

The invention discloses a preparation method of a catalyst with hydrodesulfurization, denitrification and aromatic hydrocarbon saturation performance, which comprises the following steps: taking gamma-Al2O3 or auxiliary agent modified gamma-Al2O3 as a carrier, impregnating in a first-stage impregnation liquid containing heteropolyacid salt, drying to obtain a first-stage catalyst semi-finished product, impregnating in a second-stage impregnation liquid containing active metal, and drying to obtain a second-stage catalyst semi-finished product. The heteropolyacid salt is Ni6 [WM3 (H2O) 2 (MW9O36) 2], and M is one or more of Fe, Zn, Cu and Co. The catalyst prepared by the method is beneficial to improvement of adsorption and reaction of non-hydrocarbon compounds, and desulfurization, denitrification and aromatic hydrocarbon saturation activity of the catalyst is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrofining catalysts, and relates to a preparation method of a catalyst having hydrodesulfurization, denitrification, and aromatics saturation performance. Background Art

[0002] With the accelerating trend of crude oil deterioration and heavyweight, in the hydrofining process of aviation kerosene and diesel, the sulfur, nitrogen, and aromatics contents of the feedstock oil are continuously increasing.

[0003] Sulfides are common non-hydrocarbons with relatively high contents in the kerosene fraction. When their contents are too high, they have a negative impact on the cleanliness of the engine combustion chamber. Mercaptan is an active sulfide, which is corrosive to aircraft parts and makes the oil smell bad. Therefore, there are limits on the total sulfur and mercaptan sulfur contents in the national standard of No. 3 jet fuel. The sulfides in the kerosene fraction mainly include mercaptans, sulfides, disulfides, tetrahydrothiophene, and thiophene, etc. The hydrogenation reaction activities of different types of sulfur-containing compounds increase in the following order: thiophene < tetrahydrothiophene ≈ sulfide < disulfide < mercaptan.

[0004] The content of nitrogen compounds in the kerosene fraction is generally low. Basic nitrogen compounds are the most direct cause of the color and stability problems of jet fuel. Trace amounts of basic nitrogen compounds, such as pyridine and quinoline, and phenolic substances can act synergistically to cause a decrease in color stability. Generally, when the basic nitrogen content is less than 3 μg / g, the color stability of the oil can be ensured.

[0005] The aromatics in petroleum fractions mainly include the following four categories: (1) monocyclic aromatics, including benzene, alkylbenzenes, benzocycloalkanes, etc.; (2) bicyclic aromatics, including naphthalene, alkylnaphthalenes, biphenyls, naphthocycloalkanes, etc.; (3) tricyclic aromatics, including anthracene, phenanthrene, fluorene, and their alkyl derivatives, etc.; (4) polycyclic aromatics, such as pyrene and fluoranthene, etc.

[0006] The aromatic nucleus in aromatic hydrocarbons is very stable and it is difficult to directly break the ring. The condensed and polycyclic rings of large molecules can only be ring-opened and further cracked after the aromatic rings are hydrogenated and saturated. Research shows that the aromatic hydrocarbon hydrogenation reaction has the following rules: ① The equilibrium constant of the aromatic hydrocarbon hydrogenation reaction decreases with the increase of the reaction temperature; ② In the range of 600K - 700K, the lgKp value of the equilibrium constant of the complete hydrogenation and saturation reaction of aromatic hydrocarbons decreases with the increase of the number of rings in the molecule; ③ In the range of 600K - 700K, the equilibrium constant of the hydrogenation and saturation reaction of the first ring in condensed aromatic hydrocarbons is the largest, and the equilibrium constants of the hydrogenation and saturation reactions of the second and third rings decrease in turn; ④ When the temperature exceeds 600K, the equilibrium constants of the aromatic hydrocarbon hydrogenation and saturation reactions are relatively small, so it is necessary to have a higher pressure to be beneficial to improving the equilibrium conversion rate; ⑤ The hydrogenation and saturation of the first aromatic ring in condensed aromatic hydrocarbons is relatively easy, and its relative reaction rate constant is 1.38, which is 10 times that of benzene hydrogenation, while the hydrogenation and saturation of the last remaining aromatic ring is relatively difficult, and its reaction rate is close to that of benzene.

[0007] The aromatic hydrocarbon content has a direct relationship with the smoke point of jet fuel. In the specification of No. 3 jet fuel, the volume content of aromatic hydrocarbons is required not to be greater than 20.0%, and the smoke point is not less than 25.0mm. For straight-run kerosene fractions, they mainly contain single-ring and double-ring aromatic hydrocarbons and basically do not contain aromatic hydrocarbons with three or more rings. The single-ring aromatic hydrocarbons mainly include alkylbenzenes, indanes, tetrahydronaphthalenes, indenes, and the double-ring aromatic hydrocarbons mainly include naphthalene and naphthalene derivatives. The hydrogenation and removal of single-ring and double-ring aromatic hydrocarbons is more difficult than that of polycyclic aromatic hydrocarbons. Therefore, developing a catalyst with higher aromatic hydrocarbon removal activity is of great significance for producing No. 3 jet fuel from low-smoke-point kerosene as the raw material.

[0008] In industry, the aromatic hydrocarbon saturation catalysts for distillate oils mainly include supported metal sulfide catalysts and supported noble metal catalysts. When the sulfur and nitrogen contents in the feedstock oil are relatively high, usually γ-Al 2 O 3 supported sulfided NiMo, NiW, CoMo catalysts are used. When the sulfur and nitrogen contents in the feedstock oil are low enough, using highly active supported noble metal catalysts has better effects.

[0009] The advantage of supported metal sulfide catalysts is that they are not affected by poisons in the raw materials to be treated; their disadvantage is that their hydrogenation activity is not high, and the reaction rate is very slow under normal hydrotreating conditions. To achieve a higher aromatic hydrocarbon removal depth, usually harsh reaction conditions (360 - 425°C) are required, and there are also thermodynamic equilibrium limitations on the aromatic hydrocarbon hydrogenation depth at high temperatures.

[0010] Supported noble metal catalysts are mainly used in the two-stage process where desulfurization and dearomatization are carried out separately. In the first stage, a traditional sulfide catalyst is used to reduce the sulfur content through severe hydrotreating. In the second stage, a noble metal catalyst is used for aromatic saturation. Its advantages are that it can deeply remove aromatics and the reaction conditions are relatively mild (150 - 350 °C); its disadvantage is that the catalyst in the second stage is very sensitive to sulfides in the raw materials, requiring the sulfur content in the product after the first-stage refining to be reduced to the ppm level.

[0011] Currently, there are mainly three types of dearomatization catalysts that have been studied extensively:

[0012] (1) Non-noble metal sulfided catalysts. The advantage of this type of catalyst is that it is not sensitive to the poisoning effect of sulfide species in the raw materials and has strong adaptability. It is also the most widely used in industry at present, but generally has the problem of low hydrogenation activity;

[0013] (2) Noble metal catalysts. This type of catalyst has high hydrogenation activity and can achieve deep saturation of aromatics under relatively mild conditions. However, when the raw materials contain high levels of sulfides, it is extremely easy to cause catalyst poisoning and inactivation, and the production cost is relatively high;

[0014] (3) Other types of catalysts, mainly including amorphous alloy catalysts, transition metal carbon or nitride catalysts, etc. However, the preparation conditions of these catalysts are harsh, the stability is poor, and the production cost is high, which limits their large-scale application.

[0015] Patent CN101099934A discloses a metal nitride catalyst for aromatic saturation hydrogenation. Nickel-molybdenum bimetallic nitride is supported on alumina. After stirring and impregnating at room temperature for 2 - 4 hours, it is filtered, fully dried in the air, vacuum dried at 60 - 100 °C for 5 - 8 h, tableted, sieved, and directly heated for calcination. The process is as follows: in an Ar gas stream, it is heated from room temperature to 650 - 680 °C at a rate of 10 °C / min and held for 2 h. The Ar gas space velocity is 500 - 1500 h -1 ; Switch to H 2 gas stream, hold for 2 h, and then cool to room temperature in H 2 gas. The H 2 space velocity is 500 - 1500 h -1 ; Finally, it is passivated in N 2 gas containing 1% O 2 for 4 h and is used for the saturation hydrogenation reaction of monocyclic and bicyclic aromatics, having relatively high catalytic activity. The calcination process of the catalyst prepared by this method is relatively cumbersome, the production cost is high, and it is not very economical.

[0016] Patent CN105521797B discloses a supported bimetallic component catalyst and its preparation method, including impregnating a carrier with a compound containing a first active metal component and a compound containing a second active metal component, reducing and activating the carrier, and impregnating the reduced and activated product with a solution containing a second metal active component in a reducing or inert atmosphere. The prepared catalyst has significantly higher aromatics saturation activity. The catalyst prepared by this method requires the use of precious metals, resulting in a relatively high economic cost.

[0017] Patent CN106582707B discloses a supported alloy-type aromatics saturation catalyst and its preparation method, which mainly solves the problem of low hydrogenation saturation of polycyclic aromatics in the prior art. By using a catalyst with at least one selected from alumina, silica, titanium oxide, or amorphous silica-alumina as the carrier and an alloy formed by precious metals and non-precious metals as the active component, it has the characteristic of high hydrogenation saturation activity. The catalyst prepared by this method requires the use of precious metals, resulting in a relatively high economic cost.

[0018] Patent US5308814 discloses various carrier materials for a precious metal de-aromatization catalyst composition. The carrier is prepared with Y and high-temperature resistant inorganic oxides (such as silica, alumina, or silica and alumina), and platinum and palladium are loaded. The proportion of Y zeolite in the carrier is 10 - 90%. This method uses precious metals and molecular sieves, resulting in a high production cost.

[0019] Patent CN109794299A discloses a preparation method of a hydrogenation catalyst, using molecular sieve, γ-Al 2 O 3 as the carrier and impregnating with a heteropolyacid solution to load tungsten and nickel. In order to improve the hydrogenation activity of the catalyst prepared by this method, it is necessary to introduce molecular sieve in the carrier preparation process, increasing the preparation process and cost of the catalyst. Since the hydrogenation active phase constructed by this catalyst is a traditional type II active phase and does not form a stacked structure with a specific morphology, the hydrogenation conversion effect on polar substances such as aromatics is not ideal enough, and its hydrogenation activity has limited progress compared with the mainstream catalysts on the current market, and there is still a large room for improvement. Summary of the Invention

[0020] The object of the present invention is to provide a preparation method of a catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance. The catalyst prepared by this method is beneficial to improving the adsorption and reaction of non-hydrocarbon compounds and enhancing the hydrodesulfurization, denitrification, and aromatics saturation activities of the catalyst.

[0021] To achieve the above object, the present invention provides a preparation method of a catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance, including: using γ-Al 2 O 3 or γ-Al modified with an additive 2O 3 Using [carrier] as the carrier, impregnate it with the first impregnation solution containing heteropolyacid salt, and obtain a semi-finished catalyst after drying. Then impregnate it with the second impregnation solution containing active metal, and obtain the finished catalyst after drying and calcination. The heteropolyacid salt is Ni 6 [WM 3 (H 2 O) 2 (MW 9 O 36 ) 2 , where M is one or more of Fe, Zn, Cu, and Co.

[0022] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The second impregnation solution is a stable solution containing two active metals, W and Ni. The tungsten source can be ammonium metatungstate, and the nickel source can be nickel nitrate.

[0023] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The second impregnation solution also contains one or more of citric acid, tartaric acid, and oxalic acid.

[0024] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The first impregnation solution also contains one or more of C1-C8 alcohols, which can reduce the surface tension of the solution and promote the migration of active metals in the carrier pores.

[0025] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The C1-C8 alcohols are methanol, ethanol, ethylene glycol, propanol, glycerol, butanol, butanediol, pentanol, hexanol, octanol, and methylcyclohexanol.

[0026] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The mass ratio of heteropolyacid salt to C1-C8 alcohol in the first impregnation solution is (78-95):(5-22), preferably (82-93):(7-18).

[0027] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The calcination conditions are calcination at 300°C to 600°C for 2h to 20h, preferably calcination at 380°C to 560°C for 3h to 10h.

[0028] The preparation method of the catalyst with hydrodesulfurization, denitrification, and aromatics saturation performance described in the present invention. The γ-Al 2 O 3 modified by the promoter is γ-Al 2 O 3 modified by Si and Ti.

[0029] Currently commonly used hydrogenation catalysts, typical carrier materials generally include Al 2 O 3 or modified Al 2 O 3 and the active metal components are usually supported W-Ni, Co-Mo, Mo-Ni, Co-Mo-Ni, W-Mo-Ni, etc. In the traditional loading method, the active metal is evenly dispersed on the surface of the carrier, achieving the effect of improving the utilization rate of the active metal. However, research shows that the appropriate aggregation of the active metal on the surface of the carrier, especially when the active metal forms a stacked structure with a specific morphology on the surface of the carrier, can better eliminate the steric hindrance effect, facilitate the adsorption and reaction of sulfur-containing, nitrogen-containing, and aromatic hydrocarbon molecules, and thus improve the hydrofining activity of the catalyst.

[0030] The catalyst prepared by the preparation method provided by the present invention contains two elements, Ni and W, in the active metal component. During the catalyst preparation process, by first loading an active heteropolyacid salt solution added with C1-C8 alcohols, a first-stage catalyst semi-finished product with a certain stacked morphology characteristic is formed on the carrier. The active metal loaded on the first-stage catalyst semi-finished product plays a role similar to a seed for the subsequent loaded active metal, inducing the directional loading of the subsequent active metal, and enabling the active metal to form a stacked structure with a specific morphology on the surface of the carrier. The prepared catalyst can effectively promote the adsorption and reaction of non-hydrocarbon compounds, thereby significantly improving the desulfurization, denitrification, and aromatic hydrocarbon saturation activities of the catalyst. Description of the Drawings

[0031] Figure 1 TEM photograph of the first-stage semi-finished catalyst prepared in Example 1.

[0032] Figure 2 TEM photograph of the finished catalyst prepared in Example 1.

[0033] Figure 3 TEM photograph of the first-stage semi-finished catalyst prepared in Example 2.

[0034] Figure 4 TEM photograph of the finished catalyst prepared in Example 2.

[0035] Figure 5 TEM photograph of the first-stage semi-finished catalyst prepared in Example 3.

[0036] Figure 6 TEM photograph of the finished catalyst prepared in Example 3.

[0037] Figure 7 TEM photograph of the first-stage semi-finished catalyst prepared in Example 4.

[0038] Figure 8 Transmission electron microscopy (TEM) photograph of the finished catalyst prepared in Example 4.

[0039] Figure 9 Transmission electron microscopy (TEM) photograph of the finished catalyst prepared in Comparative Example 1.

[0040] Figure 10 Transmission electron microscopy (TEM) photograph of the finished catalyst prepared in Comparative Example 2. Detailed Description of the Invention

[0041] The present invention will be specifically described below through examples. It is necessary to point out here that the following examples are only used to further illustrate the present invention and should not be construed as limiting the protection scope of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above content of the present invention.

[0042] Example 1:

[0043] Weigh 1000 g of pseudo-boehmite powder, 53 g of sesbania powder, 22 g of citric acid, and 650 ml of 3 - 5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 110 °C for 10 h, and calcine at 560 °C in an air atmosphere to obtain a γ-Al 2 O 3 support. Weigh 100 g of the prepared support, and then weigh 9.1 g and 0.9 g of Ni 6 [WCo 3 (H 2 O) 2 (CoW 9 O 36 ) 2 and ethylene glycol, add 41 g of deionized water, prepare an impregnation solution for equal-volume impregnation, and vacuum dry to prepare a first-stage catalyst. Prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, perform equal-volume impregnation on the semi-finished first-stage catalyst, and obtain the finished catalyst after vacuum drying and calcination at 400 °C for 7 h.

[0044] Example 2:

[0045] Weigh 950 g of pseudo-boehmite powder, 50 g of metatitanic acid, 45 g of sesbania powder, 22 g of citric acid, and 660 ml of 3 - 5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 120 °C for 10 h, and calcine at 540 °C in an air atmosphere to obtain a Ti-containing γ-Al 2 O 3 support. Weigh 100 g of the prepared support, and then weigh 8.2 g and 1.8 g of Ni 6 [WFe 3 (H 2 O) 2(FeW 9 O 36 ) 2 and 1,4-butanediol, add 43 g of deionized water, prepare an impregnation solution for equal-volume impregnation, and perform vacuum drying to prepare a section of catalyst. Prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, perform equal-volume impregnation on a semi-finished catalyst section, and obtain the finished catalyst after vacuum drying and calcination at 450 °C for 8 h.

[0046] Example 3:

[0047] Weigh 950 g of pseudo-boehmite powder, 50 g of silica sol, 44 g of sesbania powder, 22 g of citric acid, and 660 ml of 3-5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 120 °C for 10 h, and calcine under an air atmosphere at 540 °C to obtain γ-Al 2 O 3 support. Weigh 100 g of the prepared support, and then weigh 9.5 g and 0.5 g of Ni 6 [WZn 3 (H 2 O) 2 (ZnW 9 O 36 ) 2 and ethanol, add 42 g of deionized water, prepare an impregnation solution for equal-volume impregnation, and perform vacuum drying to prepare a section of catalyst. Prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, perform equal-volume impregnation on a semi-finished catalyst section, and obtain the finished catalyst after vacuum drying and calcination at 470 °C for 10 h.

[0048] Example 4:

[0049] Weigh 1000 g of pseudo-boehmite powder, 53 g of sesbania powder, 22 g of citric acid, and 650 ml of 3-5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 110 °C for 10 h, and calcine under an air atmosphere at 560 °C to obtain γ-Al 2 O 3 support. Weigh 100 g of the prepared support, and then weigh 8.9 g and 1.1 g of Ni 6 [WCu 3 (H 2 O) 2 (CuW 9 O 36 ) 2And methylcyclohexanol, add 41 g of deionized water, prepare an impregnation solution for equal-volume impregnation, and conduct vacuum drying to prepare a section of catalyst. Prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, conduct equal-volume impregnation on a semi-finished catalyst section, and obtain the finished catalyst after vacuum drying and calcination at 550 °C for 2 h.

[0050] Comparative Example 1:

[0051] Weigh 1000 g of pseudo-boehmite powder, 53 g of sesbania powder, 22 g of citric acid, and 650 ml of 3-5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 110 °C for 10 h, and conduct calcination treatment at 560 °C in an air atmosphere to obtain γ-Al 2 O 3 support. Weigh 100 g of the prepared support, prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, conduct equal-volume impregnation on the support, and obtain the finished catalyst after vacuum drying and calcination at 400 °C for 7 h.

[0052] Comparative Example 2:

[0053] Weigh 950 g of pseudo-boehmite powder, 50 g of metatitanic acid, 45 g of sesbania powder, 22 g of citric acid, and 660 ml of 3-5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 120 °C for 10 h, and conduct calcination treatment at 540 °C in an air atmosphere to obtain γ-Al containing Ti 2 O 3 support. Weigh 100 g of the prepared support, prepare an impregnation solution containing active metals W and Ni by mixing 12 g of ammonium metatungstate and 8.6 g of nickel nitrate, conduct equal-volume impregnation on the support, and obtain the finished catalyst after vacuum drying and calcination at 450 °C for 8 h.

[0054] Comparative Example 3

[0055] Weigh 950 g of pseudo-boehmite powder, 50 g of silica sol, 44 g of sesbania powder, 22 g of citric acid, and 660 ml of 3-5% dilute nitric acid, mix them evenly, extrude them into shape with an extruder, dry at 120 °C for 10 h, and conduct calcination treatment at 540 °C in an air atmosphere to obtain γ-Al containing Si 2 O 3 support. Weigh 100 g of the prepared support, and then weigh 17.6 g and 1.4 g of Ni respectively 6 [WZn 3 (H 2 O) 2 (ZnW 9 O 36 ) 2and ethanol, 55 g of deionized water was added, and the impregnation solution was prepared for equal-volume impregnation, followed by vacuum drying and calcination at 470 °C for 10 h to obtain the finished catalyst.

[0056] The transmission electron microscope photos of the catalysts prepared above are as Figures 1 to 10 . It can be seen from the figure that the prepared semi-finished catalyst of the first stage according to the present invention shows a relatively obvious stacking structure, and the surface of the finished catalyst has an obvious stacking structure, while this structure is not found on the surface of the catalyst prepared by the conventional method.

[0057] From Figures 1 to 8 it can be seen that compared with the corresponding semi-finished catalyst, the stacking-like morphological structure of the finished catalyst is clearer and more obvious. This is mainly because the heteropolyacid salt structure substance supported on the first-stage catalyst plays a role in modifying the surface of the alumina support, reducing the number of hydroxyl groups on the surface of the alumina support and the isoelectric point of the support, weakening the interaction between the subsequently supported active metal and the support, and promoting its moderate aggregation and growth on the surface of the heteropolyacid salt substance. The organic acids such as citric acid, tartaric acid, and oxalic acid contained in the second-stage impregnation solution also modulate the adsorption behavior of the active metal species during the secondary impregnation, playing a role similar to "template guidance" and "structural restriction" on the active metal, thus forming a structure with a specific morphology.

[0058] The above-prepared six examples of catalysts were used for the hydrogenation activity evaluation on a 200 ml scale. The feedstock oil for the evaluation was the inferior kerosene of a certain petrochemical company. The properties of the feedstock oil and the evaluation results of the examples are shown in Table 1, and the evaluation results of the comparative examples are shown in Table 2. It can be seen from Table 1 and Table 2 that compared with the two comparative examples, the hydrogenation activity of the catalysts in the examples is significantly improved, manifested in higher desulfurization and denitrification rates, and greater increases in the aromatic saturation ratio and the smoke point.

[0059] Table 1 Activity evaluation results of the catalysts in the examples

[0060] Analysis item Raw material Example 1 Example 2 Example 3 Example 4 <![CDATA[Density, g / cm 3 (at 20 °C)]]> 0.8032 0.7945 0.7946 0.7942 0.7941 Distillation range, °C Initial boiling point 176 175 174 175 175 Final boiling point 245 244 244 242 244 Sulfur content, μg / g 4380 2.0 1.9 2.1 2.0 Nitrogen content, μg / g 19.0 0.5 0.4 0.5 0.5 Smoke point, mm 20.5 27.6 27.4 27.5 27.3 Total aromatics, v% 20.9 8.4 8.3 8.0 8.5

[0061] Table 2 Activity evaluation results of the catalysts in the comparative examples

[0062]

[0063]

[0064] Note: (1) Sulfiding conditions: The catalyst was first pre-sulfided for 20 h at 330 °C in a hydrogen atmosphere using kerosene containing 2 ω% carbon disulfide under a pressure of 7.0 MPa, and then the feedstock was introduced;

[0065] (2) Reaction conditions: reaction temperature 322 °C, pressure 6.0 MPa, space velocity (volume) 1.8 h -1 , hydrogen-oil (volume) ratio 300.

[0066] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention. However, these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties, characterized in that: include: The first stage impregnation liquid containing heteropoly acid salt is impregnated with γ-Al2O3 or γ-Al2O3 modified by an additive as a carrier, and a first stage catalyst semi-finished product is obtained after drying, and then impregnated with a second stage impregnation liquid containing active metal, and a finished catalyst is obtained after drying and roasting. The heteropoly acid salt is Ni6[WM3(H2O)2(MW9O 36 )2], M is one or more of Fe, Zn, Cu, and Co.

2. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 1, characterized in that: The second stage impregnation solution is a stable solution containing two active metals, W and Ni.

3. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 1, characterized in that: The second stage impregnation solution also contains one or more of citric acid, tartaric acid and oxalic acid.

4. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 1, characterized in that: The first stage impregnation solution also contains one or more of C1 to C8 alcohols.

5. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 4, characterized in that: The C1-C8 alcohols are methanol, ethanol, ethylene glycol, propanol, glycerol, butanol, butanediol, pentanol, hexanol, octanol and methylcyclohexanol.

6. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 4, characterized in that: The mass ratio of the heteropoly acid salt to the C1-C8 alcohol in the first stage impregnation solution is (78-95):(5-22).

7. The method for preparing a catalyst having hydrodesulfurization, denitrification and aromatic saturation performance according to claim 1, characterized in that: The calcination conditions are 300°C to 600°C for 2h to 20h.

8. The method for preparing a catalyst having hydrodesulfurization, denitrogenation and aromatic saturation properties according to claim 1, characterized in that: The additive-modified γ-Al2O3 is Si- and Ti-modified γ-Al2O3.

Images