Catalytic diesel hydroprocessing catalyst and method for making same

Abstract

The application discloses a catalytic diesel oil hydrogenation catalyst and a preparation method thereof. The preparation method comprises the following steps: (1) preparing a carrier precursor; (2) preparing a pretreatment solution; (3) preparing a carrier; and (4) preparing a catalyst. The application further provides a catalytic diesel oil hydrogenation catalyst, which comprises a carrier, an active metal component supported on the carrier and an optional additive. The carrier is a composite carrier containing a molecular sieve and alumina. The active metal component comprises at least one of a group VIB metal element and at least one of a group VIII metal element, and the additive is phosphorus pentoxide. The catalyst not only has high hydrogenation activity and impurity removal capacity, but also has high cracking performance, and can realize gradual reactions of hydrogenation and cracking on one catalyst, so that the hydrogenation activity and the cracking activity can be effectively matched, and the catalyst is especially suitable for a catalytic diesel oil hydrogenation conversion process.

Description

Technical Field

[0001] This invention belongs to the field of oil refining and chemical technology, and relates to a hydrogenation catalyst and its preparation method, particularly to a catalytic diesel hydrogenation catalyst and its preparation method. Background Technology

[0002] In recent years, with the development of my country's economy, the demand structure for oil products has changed. The demand for gasoline and jet fuel has increased, while the growth rate of diesel demand has decreased or even turned negative. Since 2006, the diesel-to-gasoline ratio in my country's consumption has shown a gradual downward trend. On the other hand, with the increasing awareness of environmental protection, the requirements for oil quality are becoming increasingly stringent. From 2015 to 2019, fuel oil standards were upgraded from National IV to National VI. For diesel, the significant changes were the increasingly stringent requirements for indicators such as sulfur content, cetane number, and polycyclic aromatic hydrocarbons. However, with the increasing quality of crude oil processed domestically, the feedstock for catalytic cracking is also becoming increasingly heavy and of lower quality. Furthermore, many enterprises have modified or increased the operational severity of catalytic cracking units to improve gasoline quality or increase propylene production, leading to a further deterioration in the quality of catalytic cracking products, especially catalytic diesel. Therefore, research on the efficient conversion of catalytic diesel into high-value products needed by the market has attracted widespread attention from refineries.

[0003] Catalytic diesel fuel mainly contains short-chain bicyclic aromatics, with a small amount of short-chain tricyclic aromatics. Based on the conversion process of bicyclic and tricyclic aromatics, hydrocracking technology can convert low-value polycyclic aromatics into high-value monocyclic aromatics such as alkylbenzenes and BTX, which is an ideal way to solve the current overcapacity of diesel fuel and the shortage of low-carbon aromatics.

[0004] The core of catalytic diesel hydroconversion technology is the catalyst. Existing hydrocracking catalysts and hydrorefining catalysts cannot simultaneously meet the requirements of catalytic diesel hydrocracking, cracking and aromatics-oriented conversion performance. Generally, catalyst gradation is used to achieve catalytic diesel hydrorefining and hydrocracking. How to achieve the function of hydrorefining followed by hydrocracking on a single catalyst and improve the yield of the target product has always been the goal pursued by researchers.

[0005] CN200710158784.0 This invention discloses a hydrocracking catalyst for high heavy naphtha production and its preparation method. The catalyst contains a hydrocracking active metal and a support composed of a modified Y-type molecular sieve and alumina. The Y-type molecular sieve is obtained by hydrothermal treatment with a mixed aqueous solution of aluminum salt and acid. The modified Y-type molecular sieve has the following properties: specific surface area 750 μm. 2 / g~850m 2The catalyst exhibits the following characteristics: total pore volume 0.35 ml / g–0.48 ml / g; relative crystallinity 90%–130%; cell parameter 2.437–2.445 nm; silicon-aluminum molar ratio 15–70; infrared acidity 0.5–1.0 mmol / g; Brønsted acid / Low acid ratio greater than 7.0; and sodium oxide content ≤0.05 wt%. This hydrocracking catalyst demonstrates good catalytic activity, high selectivity and yield of heavy naphtha, and high aromatic hydrocarbon potential in heavy naphtha.

[0006] CN201811264077.4 discloses a catalytic diesel hydroconversion catalyst, its preparation method, and its application. The hydroconversion catalyst, based on its total weight, contains 30-70% modified Y-type molecular sieve and 0.01-0.1% carbon. The ratio of the total pyridine infrared acidity to the total n-butylpyridine infrared acidity in the modified Y-type molecular sieve is 1-1.2, and the total pyridine infrared acidity is 0.1-1.2 mmol / g. Based on the total amount of the modified Y-type molecular sieve, it contains 0.5-2.0% Na₂O. The hydroconversion catalyst is prepared by a kneading method or an impregnation method, preferably using the following method. This catalyst exhibits excellent selective ring-opening conversion ability of polycyclic hydrocarbons and good reaction selectivity, which can significantly improve the quality of gasoline and diesel products from catalytic diesel hydroconversion. Simultaneously, the yield of the reaction liquid products is high. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, the main objective of this invention is to provide a catalytic diesel hydrotreating catalyst, its preparation method, and its application. The catalyst not only possesses high hydrogenation activity and impurity removal capability but also high cracking performance, enabling a gradual reaction of hydrogenation followed by cracking on a single catalyst. The hydrogenation activity and cracking activity are effectively matched, making it particularly suitable for catalytic diesel hydroconversion processes.

[0008] The technical solution of the present invention includes the following aspects, as detailed below:

[0009] I. A method for preparing a catalytic diesel hydrogenation catalyst, comprising the following steps:

[0010] (1) Preparation of carrier precursor: Mix molecular sieve and an aqueous solution of organic polymer that has been heated, and then obtain the carrier precursor by spheroidizing process;

[0011] (2) Preparation of pretreatment solution: Under contact conditions, organic polymer, organic acid and water are mixed and heated to obtain pretreatment solution;

[0012] (3) Preparation of carrier: The carrier precursor obtained in step (1) is placed in a ball rolling machine. During the rolling process, pseudo-boehmite powder, the pretreatment solution obtained in step (2), and the aqueous solution of the organic polymer after heat treatment are uniformly introduced. Then, the carrier is obtained by first drying and first calcination.

[0013] (4) Preparation of catalyst: Under contact conditions, the support obtained in step (3) is mixed with an impregnation solution containing a Group VIII metal compound, a Group VIB metal compound, and an optional phosphorus-containing compound, and then subjected to a second drying and a second calcination to obtain a catalytic diesel hydrogenation catalyst.

[0014] Furthermore, according to a preferred embodiment of the present invention, the molecular sieve mentioned in step (1) is one or more of Y-type molecular sieve, β molecular sieve, ZSM-5 molecular sieve, SAPO molecular sieve, and MCM-41 molecular sieve. The particle size of the molecular sieve is greater than 200 mesh. When used, the molecular sieve can be processed by a ball mill or other processing device to obtain a molecular sieve sample with the required particle size. Furthermore, the molecular sieve can also be appropriately modified. The modification method can be any of the existing molecular sieve modification methods.

[0015] Furthermore, according to a preferred embodiment of the present invention, the molecular sieve mentioned in step (1) is a Y-type molecular sieve, and more specifically, the properties of the Y-type molecular sieve are as follows: pore volume of 0.30~0.60cm³. 3 / g, specific surface area of ​​700-1000m² 2 / g, total acidity in infrared is 0.5-1.1 mmol / g, relative crystallinity is 90%-120%, SiO2 / Al2O3 molar ratio is 10-30, and cell parameter is 2.436-2.450 nm.

[0016] Furthermore, according to a preferred embodiment of the present invention, the mass fraction of the aqueous solution of the heat-treated organic polymer in steps (1) and (3) is 0.5wt% to 8.0wt%, preferably 1.0wt% to 5.0wt%. The preparation process of the aqueous solution of the heat-treated organic polymer is as follows: the mixture of organic polymer and water is heated at 60 to 100°C until the organic polymer is completely dissolved to obtain the aqueous solution of the heat-treated organic polymer. The heating time is 10 to 40 minutes.

[0017] Furthermore, according to a preferred embodiment of the present invention, the weight ratio of the aqueous solution of the organic polymer to the molecular sieve in step (1) is 0.5 to 1.5.

[0018] Furthermore, according to a preferred embodiment of the present invention, the spherical forming in step (1) can be any of the existing spherical forming methods in the art, specifically one or more of extrusion ball-throwing forming and roll forming.

[0019] Furthermore, according to a preferred embodiment of the present invention, the organic acid in step (2) may be selected from one or more of citric acid, acetic acid, lactic acid, malic acid, and tartaric acid, preferably citric acid.

[0020] Furthermore, according to a preferred embodiment of the present invention, the organic polymer is one or more of starch, cellulose ether, and flour, preferably starch. More specifically, the starch is one or more of mung bean starch, tapioca starch, sweet potato starch, potato starch, wheat starch, water chestnut starch, lotus root starch, and corn starch, preferably corn starch and / or potato starch; the cellulose ether can be at least one of methylcellulose, hydroxyethyl methylcellulose, carboxymethyl cellulose, ethylcellulose, benzylcellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, cyanoethylcellulose, benzyl cyanoethylcellulose, carboxymethyl hydroxyethyl cellulose, and phenylcellulose, preferably methylcellulose.

[0021] Furthermore, according to a preferred embodiment of the present invention, the mass ratio of the organic polymer to water in step (2) is 0.1 to 0.5, and the mass ratio of the organic polymer to the organic acid is 1:0.1 to 1:4.

[0022] Furthermore, according to a preferred embodiment of the present invention, the heating temperature in step (2) is 30-50°C and the treatment time is 2-6 hours.

[0023] Furthermore, according to a preferred embodiment of the present invention, the amount of organic polymer added in step (2) is 5wt% to 25wt% of the dry basis mass of the boehmite powder, preferably 10wt% to 20wt%.

[0024] Furthermore, according to a preferred embodiment of the present invention, the pseudoboehmite powder mentioned in step (3) can be a commercially available product that meets the product properties, or it can be prepared using methods disclosed in existing patents or literature. More preferably, the pseudoboehmite powder, after calcination at 600°C, has the following properties: specific surface area greater than 300 m². 2 / g, preferably 330-370m 2 / g, with a pore volume of 0.5 to 0.9 mL / g, preferably 0.55 to 0.85 mL / g.

[0025] Furthermore, according to a preferred embodiment of the present invention, the content of organic polymer in the pretreatment solution obtained in step (2) of step (3) is 10wt% to 20wt% of the dry basis mass of boehmite powder in step (3).

[0026] Furthermore, according to a preferred embodiment of the present invention, the amount of the aqueous solution of the heat-treated organic polymer added in step (3) is 0.1 to 1.0 of the mass of the boehmite powder.

[0027] Furthermore, according to a preferred embodiment of the present invention, the first drying temperature in step (3) is 70-120°C; the first drying time is 8-12h.

[0028] Furthermore, according to a preferred embodiment of the present invention, the first calcination in step (3) is carried out in the presence of an inert atmosphere, which is nitrogen and / or an inert gas, which may be one or more of helium, neon, argon, krypton, and xenon; preferably nitrogen; the first calcination temperature is 550 to 700°C, and the first calcination time is 1 to 5 hours.

[0029] Furthermore, according to a preferred embodiment of the present invention, the particle size of the carrier in step (3) is 0.3 to 2.0 mm, preferably 0.5 to 1.8 mm.

[0030] Furthermore, according to a preferred embodiment of the present invention, the Group VIB metal in step (4) is generally Mo and / or W, and the Group VIII metal is generally Ni and / or Co.

[0031] Furthermore, according to a preferred embodiment of the present invention, the group VIB metal compound in step (4) may be derived from one or more of the molybdenum-containing compounds and tungsten-containing compounds; more specifically, the molybdenum-containing compound may be molybdenum oxide and / or ammonium heptamolybdate; the tungsten-containing compound may be ammonium metatungstate.

[0032] Furthermore, according to a preferred embodiment of the present invention, the group VIII metal compound in step (4) may be derived from one or more of nickel-containing compounds and cobalt-containing compounds; the nickel-containing compound may be basic nickel carbonate and / or nickel nitrate; the cobalt-containing compound may be basic cobalt carbonate and / or cobalt nitrate.

[0033] Furthermore, according to a preferred embodiment of the present invention, the phosphorus-containing compound in step (4) may be one or more of phosphoric acid, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate.

[0034] Furthermore, according to a preferred embodiment of the present invention, the second drying operation conditions in step (4) are as follows: the second drying temperature is 80-120°C, and the second drying time is 4-12h.

[0035] Furthermore, according to a preferred embodiment of the present invention, the second calcination operation conditions in step (4) are as follows: the second calcination temperature is 400-600°C, and the second calcination time is 1-5 hours. The second calcination is generally carried out under air and oxygen atmosphere conditions.

[0036] Furthermore, according to a preferred embodiment of the present invention, the process of preparing the catalyst in step (4) is as follows: first, a group VIII metal compound, a group VIB metal compound, and an optional phosphorus-containing compound are mixed and mixed evenly to obtain an impregnation solution. The concentration of the metal (group VIII metal and group VIB metal) component in the impregnation solution is 0.05 to 1.0 g / mL (calculated as metal oxide), and the concentration of P is 0 to 0.1 g / mL. Then, the support obtained in step (3) is mixed with the impregnation solution and subjected to a second drying and a second calcination to obtain a catalytic diesel hydrogenation catalyst.

[0037] A second aspect of the present invention provides a catalytic diesel hydrogenation catalyst, which is obtained by the preparation method provided in the first aspect of the present invention as described above.

[0038] Furthermore, according to a preferred embodiment of the present invention, the catalytic diesel hydrotreating catalyst includes a support, an active metal component supported on the support, and optional additives; the support is a composite support containing molecular sieves and alumina; the active metal component includes at least one group VIB metal element and at least one group VIII metal element, and the additive is phosphorus pentoxide.

[0039] Furthermore, according to a preferred embodiment of the present invention, the support for the catalytic diesel hydrotreating catalyst is spherical and has a core-shell structure, with molecular sieve as the core layer and alumina as the shell layer. Based on the weight of the support, the molecular sieve content is 30%–75%; the alumina content is 25%–70%.

[0040] Furthermore, according to a preferred embodiment of the present invention, the catalytic diesel hydrotreating catalyst has the following properties: a specific surface area of ​​150–250 m². 2 The pore volume is 0.40–0.70 mL / g, with mesopores of 10–50 nm accounting for 50%–85% of the total pore volume. The total acid value is 0.40–0.70 mmol / g, and the lateral compressive strength is greater than 15 N / mm.

[0041] Furthermore, according to a preferred embodiment of the present invention, in the above-mentioned catalytic diesel hydrogenation catalyst support, the diameter of the support particles is 0.3 to 2.0 mm, preferably 0.5 to 1.8 mm.

[0042] Furthermore, according to a preferred embodiment of the present invention, during the preparation process, the amounts of each component are such that, based on the final catalyst and calculated as oxides, the content of the Group VIB metal component is 10wt% to 25wt%; the content of the Group VIII metal component is 2wt% to 7wt%; and the content of the auxiliary agent phosphorus pentoxide is 2.0wt% to 6.0wt%.

[0043] Furthermore, according to a preferred embodiment of the present invention, in the active metal component, the Group VIB metal element is preferably selected from Mo and / or W, and the Group VIII metal element is preferably selected from Ni and / or Co. Even further, the active metal component is more preferably Mo and Ni.

[0044] A third aspect of the present invention provides a catalytic diesel hydrotreating process, wherein, under hydrotreating process conditions, catalytic diesel feedstock and hydrogen are contacted with the catalytic diesel hydrotreating catalyst provided in the second aspect above to react.

[0045] Furthermore, according to a preferred embodiment of the present invention, the catalytic diesel oil generally has the following properties: density (20°C) of 0.88–0.98 g / cm³. 3 The dry point is generally 360-400℃, the aromatic content is generally 50wt%-90wt%, the sulfur content is 0.2wt%-2.0wt%, and the nitrogen content is 500-2100 μg / g.

[0046] Furthermore, according to a preferred embodiment of the present invention, the hydrogenation process conditions are generally as follows: reaction pressure of 5–12 MPa, reaction temperature of 360–430 °C, and liquid hourly space velocity of 0.3–3.0 h⁻¹. -1 The hydrogen-to-oil volume ratio is 100–1000.

[0047] Furthermore, according to a preferred embodiment of the present invention, the catalytic diesel hydrotreating process can employ a fluidized bed hydrotreating process and / or a fixed bed hydrotreating process.

[0048] Compared with the prior art, the catalytic diesel hydrogenation catalyst and its preparation method provided by the present invention have the following advantages:

[0049] 1. In the preparation method of the catalytic diesel hydrogenation catalyst of this invention, the organic polymer is heated and decomposed into small molecules in water, giving the aqueous solution high adhesiveness. During the pelleting process, this enables strong interactions between molecular sieves, overcoming the poor adhesiveness of molecular sieves. Simultaneously, it also enhances the interaction between the molecular sieves and alumina, improving the strength and wear resistance of the support. Furthermore, the organic polymer is modified with organic acids, reducing its molecular size and viscosity. When mixed with boehmite powder, it increases the mesopore ratio of the alumina support, thus expanding the pores.

[0050] 2. In the preparation method of the catalytic diesel hydrogenation catalyst of the present invention, the organic acid modified by the organic polymer interacts with the basic sites on the alumina and is adsorbed. Calcination under an inert atmosphere or a nitrogen atmosphere causes the organic acid to generate carbon in situ at the basic sites of the alumina support. On the one hand, this can act as a barrier to the active metal, preventing the active metal from migrating and agglomerating during low-temperature calcination, which is beneficial to improving the dispersion of the active metal on the support. On the other hand, it can avoid strong interaction between the active metal and the basic sites of the support during calcination, making the active metal on the catalyst easier to sulfide. Finally, calcination in an oxygen-containing atmosphere burns off the carbon, restoring the basic sites of the alumina.

[0051] 3. In the preparation method of the catalytic diesel hydrogenation catalyst of the present invention, the carbon material generated by the organic acid-modified organic polymer on the alumina support is completely burned off during the catalyst calcination process, which increases the number of mesopores in the alumina support and plays a role in expanding the pores of the alumina support. This gives the catalyst more reactant diffusion and reaction channels, allowing impurities in the catalytic diesel to be better removed. It also protects the molecular sieve catalyst in the core and ensures the long-term stability of the catalyst.

[0052] 4. In the preparation method of the catalytic diesel hydrogenation catalyst of the present invention, a spherical catalytic diesel hydrogenation catalyst with a core-shell structure is provided. The catalyst has a molecular sieve as the core layer and an alumina as the shell layer. The catalyst can realize the gradual reaction of catalytic diesel hydrogenation followed by cracking. The catalyst has high activity and stability and can realize the catalytic diesel hydrogenation conversion to produce gasoline high octane blending components or BTX, supporting the transformation of oil refining to chemical industry. Detailed Implementation

[0053] The technical solution and effects of the present invention are further illustrated below through specific embodiments. In the present invention, wt% is the mass fraction.

[0054] The analytical methods of this invention are as follows: Specific surface area, pore volume, external specific surface area, and pore distribution were measured using the cryogenic liquid nitrogen physical adsorption method, with the instrument being an ASAP2420 physical adsorption instrument manufactured by a US company. Infrared acidity was measured using pyridine adsorption infrared spectroscopy, with a NICOLET 6700 Fourier transform infrared spectrometer. The wear index of microsphere carriers <0.8 mm was tested using the high-speed air jet method (see ASTM D5757-00), and the wear index of microsphere carriers >0.8 mm was measured using the drum method, with a KM-ZV abrasion tester. Lateral compressive strength was measured using a ZQJ-II intelligent particle strength testing machine.

[0055] Example 1

[0056] (1) Carrier preparation

[0057] The material with a pore volume of 0.45 mL / g and a specific surface area of ​​810 m² was milled using a ball mill. 2 Y-type molecular sieves with a relative crystallinity of 98%, a SiO2 / Al2O3 molar ratio of 12, a cell parameter of 2.446 nm, and an infrared total acidity of 0.8 mmol / g were ground to a particle size of 1.5 μm. 80 g of corn starch was added to 2000 g of water and heated at 70 °C for 20 min to obtain a heat-treated aqueous solution of the organic polymer. 400 g of Y-type molecular sieve was mixed with 320 g of the heat-treated organic polymer aqueous solution, and then spheroidized to obtain a carrier precursor. 42 g of corn starch, 42 g of citric acid, and 140 g of water were mixed thoroughly and heated to 40 °C for 3 h to obtain a pretreated solution. The prepared carrier precursor was placed in a ball rolling mill, and 600 g of pseudoboehmite powder (specific surface area 350 μm) was uniformly introduced during the rolling process. 2 The mixture of a pretreated solution (containing 0.8 mL / g of organic polymer with a pore volume of 0.8 mL / g) and 400 g of an aqueous solution of a heat-treated organic polymer was dried at 90 °C for 10 h, and then calcined at 600 °C for 3 h under a nitrogen atmosphere to obtain spherical carriers with a diameter of 0.5-0.8 mm. The carrier yield and wear data are shown in Table 1.

[0058] (2) Catalyst preparation

[0059] Dissolve 10.18 g of phosphoric acid H3PO4 (concentration 85 wt%) in 80 mL of water, then add 27.62 g of molybdenum trioxide and 12.14 g of basic nickel carbonate, heat to 100 °C and stir under reflux for 2.0 h, filter and bring the volume to 85 mL to obtain the Mo-Ni-P aqueous solution.

[0060] The entire Mo-Ni-P aqueous solution was added to 100g of the prepared support, mixed thoroughly, and allowed to stand for 2h. Then, it was dried at 110℃ for 8h and calcined at 550℃ for 3h to obtain the catalyst, which contained 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0061] (3) Catalyst evaluation

[0062] The catalyst was evaluated over a long period using a CSTR hydrogenation evaluation system, with an operating time of 1500 hours. The evaluation conditions were: reaction temperature 390℃, reaction pressure 10.0 MPa, and volume hourly space velocity (VHSV) 0.4 h⁻¹. -1 The hydrogen-to-oil volume ratio was 600:1. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0063] Example 2

[0064] (1) Carrier preparation

[0065] The material with a pore volume of 0.45 mL / g and a specific surface area of ​​810 m² was milled using a ball mill. 2 Y-type molecular sieves with a relative crystallinity of 98%, a SiO2 / Al2O3 molar ratio of 12, a cell parameter of 2.446 nm, and an infrared total acidity of 0.8 mmol / g were ground to a particle size of 1.5 μm. 80 g of corn starch was added to 2000 g of water and heated at 70 °C for 20 min to obtain a heat-treated aqueous solution of the organic polymer. 500 g of Y-type molecular sieve was mixed with 400 g of the heat-treated organic polymer aqueous solution, and then spheroidized to obtain a carrier precursor. 52.5 g of corn starch, 52.5 g of citric acid, and 175 g of water were mixed, heated to 40 °C for 3 h to obtain a pretreated solution. The prepared carrier precursor was placed in a ball rolling mill, and 500 g of pseudoboehmite powder (specific surface area 350 μm) was uniformly introduced during the rolling process. 2 The mixture of a pretreated solution (containing 0.8 mL / g of organic polymer with a pore volume of 0.8 mL / g) and 280 g of an aqueous solution of a heat-treated organic polymer was dried at 90 °C for 10 h, and then calcined at 650 °C for 3 h under a nitrogen atmosphere to obtain spherical carriers with a diameter of 0.5-0.8 mm. The carrier yield and wear data are shown in Table 1.

[0066] (2) Catalyst preparation

[0067] Dissolve 10.18 g of phosphoric acid H3PO4 (concentration 85 wt%) in 80 mL of water, then add 27.62 g of molybdenum trioxide and 12.14 g of basic nickel carbonate, heat to 100 °C and stir under reflux for 2.0 h, filter and bring the volume to 85 mL to obtain the Mo-Ni-P aqueous solution.

[0068] The entire Mo-Ni-P aqueous solution was added to 100g of the prepared support, mixed thoroughly, and allowed to stand for 2h. Then, it was dried at 110℃ for 8h and calcined at 550℃ for 3h to obtain the catalyst, which contained 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0069] (3) Catalyst evaluation

[0070] The catalyst was evaluated over a long period using a CSTR hydrogenation evaluation system, with an operating time of 1500 hours. The evaluation conditions were: reaction temperature 390℃, reaction pressure 10.0 MPa, and volume hourly space velocity (VHSV) 0.4 h⁻¹. -1 The hydrogen-to-oil volume ratio was 600:1. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0071] Example 3

[0072] (1) Carrier preparation

[0073] The material with a pore volume of 0.45 mL / g and a specific surface area of ​​810 m² was milled using a ball mill. 2 Y-type molecular sieves with a relative crystallinity of 98%, a SiO2 / Al2O3 molar ratio of 12, a cell parameter of 2.446 nm, and an infrared total acidity of 0.8 mmol / g were ground to a particle size of 1.5 μm. 80 g of corn starch was added to 2000 g of water and heated at 70 °C for 20 min to obtain a heat-treated aqueous solution of the organic polymer. 600 g of Y-type molecular sieve was mixed with 480 g of the heat-treated organic polymer aqueous solution, and then spheroidized to obtain a carrier precursor. 56 g of corn starch, 56 g of citric acid, and 190 g of water were mixed, heated to 40 °C for 3 h, and a pretreated solution was obtained. The prepared carrier precursor was placed in a ball rolling mill, and 400 g of pseudoboehmite powder (specific surface area 350 μm) was uniformly introduced during the rolling process. 2 The mixture of a pretreated solution (containing 0.8 mL / g of organic polymer with a pore volume of 0.8 mL / g) and an aqueous solution of 170 g of heat-treated organic polymer was dried at 90 °C for 10 h, and then calcined at 700 °C for 3 h under a nitrogen atmosphere to obtain spherical carriers with a diameter of 0.5-0.8 mm. The carrier yield and wear data are shown in Table 1.

[0074] (2) Catalyst preparation

[0075] Dissolve 10.18 g of phosphoric acid H3PO4 (concentration 85 wt%) in 80 mL of water, then add 27.62 g of molybdenum trioxide and 12.14 g of basic nickel carbonate, heat to 100 °C and stir under reflux for 2.0 h, filter and bring the volume to 85 mL to obtain the Mo-Ni-P aqueous solution.

[0076] The entire Mo-Ni-P aqueous solution was added to 100g of the prepared support, mixed thoroughly, and allowed to stand for 2h. Then, it was dried at 110℃ for 8h and calcined at 550℃ for 3h to obtain the catalyst, which contained 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0077] (3) Catalyst evaluation

[0078] The catalyst was evaluated over a long period using a CSTR hydrogenation evaluation system, with an operating time of 1500 hours. The evaluation conditions were: reaction temperature 390℃, reaction pressure 10.0 MPa, and volume hourly space velocity (VHSV) 0.4 h⁻¹. -1 The hydrogen-to-oil volume ratio was 600:1. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0079] Example 4

[0080] The preparation was essentially the same as in Example 3, except that corn starch was replaced with potato starch to obtain a spherical support with a particle size of 0.5~0.8 mm. The support yield and wear data are shown in Table 1. A catalyst was prepared, in which the content of MoO3 was 20.0 wt%, the content of NiO was 5.0 wt%, and the content of P was 2.0 wt%. The physicochemical properties of the catalyst are shown in Table 2.

[0081] The catalyst was evaluated in the same way as in Example 3. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0082] Example 5

[0083] The preparation was essentially the same as in Example 3, except that 80g of corn starch was replaced with 67.41g of methylcellulose and 56g of corn starch was replaced with 47.19g of methylcellulose, resulting in a spherical support with a particle size of 0.5~0.8mm. The support yield and wear data are shown in Table 1. A catalyst was prepared, containing 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0084] The catalyst was evaluated in the same way as in Example 3. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0085] Example 6

[0086] The preparation was essentially the same as in Example 3, except that the 0.5-0.8 mm spherical support was replaced with a 1.2-1.5 mm spherical support. Support yield and wear data are shown in Table 1. A catalyst was prepared, containing 20.0 wt% MoO3, 5.0 wt% NiO, and 2.0 wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0087] The catalyst was evaluated in the same way as in Example 3. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0088] Comparative Example 1

[0089] (1) Carrier preparation

[0090] The material with a pore volume of 0.45 mL / g and a specific surface area of ​​810 m² was milled using a ball mill. 2 Y-type molecular sieves with a relative crystallinity of 98%, a SiO2 / Al2O3 molar ratio of 12, a cell parameter of 2.446 nm, and an infrared total acidity of 0.8 mmol / g were ground into powder with a particle size of 1.5 μm. 400 g of Y-type molecular sieve, 12.8 g of corn starch, and 320 g of water were mixed and then spheroidized to obtain a carrier precursor. 42 g of corn starch, 42 g of citric acid, and 140 g of water were mixed, heated to 40 °C, and treated for 3 h to obtain a pretreated solution. The prepared carrier precursor was placed in a ball rolling mill, and 600 g of pseudoboehmite powder (specific surface area 350 μm) was uniformly introduced during the rolling process. 2 The mixture of 16 g corn starch and 400 g water (with a pore volume of 0.8 mL / g), a pretreatment solution, and 0.8 mL / g spherical carriers was prepared by drying the resulting material at 90 °C for 10 h and then calcining it at 600 °C for 3 h under a nitrogen atmosphere to obtain 0.5-0.8 mm spherical carriers. The carrier yield and abrasion data are shown in Table 1.

[0091] (2) Catalyst preparation

[0092] Dissolve 10.18 g of phosphoric acid H3PO4 (concentration 85 wt%) in 80 mL of water, then add 27.62 g of molybdenum trioxide and 12.14 g of basic nickel carbonate, heat to 100 °C and stir under reflux for 2.0 h, filter and bring the volume to 85 mL to obtain the Mo-Ni-P aqueous solution.

[0093] The entire Mo-Ni-P aqueous solution was added to 100g of the prepared support, mixed thoroughly, and allowed to stand for 2h. Then, it was dried at 110℃ for 8h and calcined at 550℃ for 3h to obtain the catalyst, which contained 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0094] (3) Catalyst evaluation

[0095] The catalyst was evaluated over a long period using a CSTR hydrogenation evaluation system, with an operating time of 1500 hours. The evaluation conditions were: reaction temperature 390℃, reaction pressure 10.0 MPa, and volume hourly space velocity (VHSV) 0.4 h⁻¹. -1 The hydrogen-to-oil volume ratio was 600:1. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0096] Comparative Example 2

[0097] (1) Carrier preparation

[0098] The material with a pore volume of 0.45 mL / g and a specific surface area of ​​810 m² was milled using a ball mill. 2 Y-type molecular sieves with a relative crystallinity of 98%, a SiO2 / Al2O3 molar ratio of 12, a cell parameter of 2.446 nm, and an infrared total acidity of 0.8 mmol / g were ground to a particle size of 1.5 μm. 80 g of corn starch was added to 2000 g of water and heated at 70 °C for 20 min to obtain a heat-treated aqueous solution of the organic polymer. 400 g of Y-type molecular sieve was mixed with 320 g of the heat-treated aqueous solution of the organic polymer, and then spheroidized to obtain a carrier precursor. 42 g of corn starch and 140 g of water were mixed thoroughly and heated to 40 °C for 3 h to obtain a pretreated solution. The prepared carrier precursor was placed in a ball rolling mill, and 600 g of pseudoboehmite powder (specific surface area 350 μm) was uniformly introduced during the rolling process. 2 The mixture of a pretreated solution (containing 0.8 mL / g of organic polymer with a pore volume of 0.8 mL / g) and 400 g of an aqueous solution of a heat-treated organic polymer was dried at 90 °C for 10 h, and then calcined at 600 °C for 3 h under a nitrogen atmosphere to obtain spherical carriers with a diameter of 0.5-0.8 mm. The carrier yield and wear data are shown in Table 1.

[0099] (2) Catalyst preparation

[0100] Dissolve 10.18 g of phosphoric acid H3PO4 (concentration 85 wt%) in 80 mL of water, then add 27.62 g of molybdenum trioxide and 12.14 g of basic nickel carbonate, heat to 100 °C and stir under reflux for 2.0 h, filter and bring the volume to 85 mL to obtain the Mo-Ni-P aqueous solution.

[0101] The entire Mo-Ni-P aqueous solution was added to 100g of the prepared support, mixed thoroughly, and allowed to stand for 2h. Then, it was dried at 110℃ for 8h and calcined at 550℃ for 3h to obtain the catalyst, which contained 20.0wt% MoO3, 5.0wt% NiO, and 2.0wt% P. The physicochemical properties of the catalyst are shown in Table 2.

[0102] (3) Catalyst evaluation

[0103] The catalyst was evaluated over a long period using a CSTR hydrogenation evaluation system, with an operating time of 1500 hours. The evaluation conditions were: reaction temperature 390℃, reaction pressure 10.0 MPa, and volume hourly space velocity (VHSV) 0.4 h⁻¹. -1 The hydrogen-to-oil volume ratio was 600:1. The properties of the feedstock oil used are shown in Table 3, and the evaluation results are shown in Table 4.

[0104] Table 1 Carrier yield and wear

[0105]

[0106] Table 2 Physicochemical properties of catalysts

[0107]

[0108] Table 3 Properties of Feed Oil

[0109]

[0110] Table 4 Catalyst Evaluation Results

[0111]

[0112] The activity, <210℃ fraction yield, and C6-C9 light aromatic hydrocarbon content of Comparative Example 1 were all set to 100. Other evaluation results compared with the activity of the Comparative Example are shown in Table 4.

Claims

1. A method for preparing a catalytic diesel hydrogenation catalyst, comprising the following steps: (1) Preparation of carrier precursor: Mix molecular sieve and an aqueous solution of organic polymer that has been heated, and then obtain the carrier precursor by spheroidizing process; (2) Preparation of pretreatment solution: Under contact conditions, organic polymer, organic acid and water are mixed and heated to obtain pretreatment solution; (3) Preparation of carrier: The carrier precursor obtained in step (1) is placed in a ball rolling machine. During the rolling process, pseudo-boehmite powder, the pretreatment solution obtained in step (2), and the aqueous solution of the organic polymer after heat treatment are uniformly introduced. Then, the carrier is obtained by first drying and first calcination. (4) Preparation of catalyst: Under contact conditions, the support obtained in step (3) is mixed with an impregnation solution containing Group VIII metal compounds, Group VIB metal compounds and phosphorus-containing compounds, and then subjected to a second drying and a second calcination to obtain a catalytic diesel hydrogenation catalyst; the phosphorus-containing compound is one or more of phosphoric acid, ammonium dihydrogen phosphate and diammonium hydrogen phosphate. in, The organic polymer is one or more of starch, cellulose ether, and flour; The preparation process of the aqueous solution of the organic polymer after heat treatment in steps (1) and (3) is as follows: the mixture of organic polymer and water is heated at 60-100℃, and the aqueous solution of the organic polymer after heat treatment is obtained after the organic polymer is completely dissolved.

2. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The molecular sieve mentioned in step (1) is one or more of the following: Y-type molecular sieve, β-molecular sieve, ZSM-5 molecular sieve, SAPO molecular sieve, and MCM-41 molecular sieve.

3. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1 or 2, characterized in that: The molecular sieve mentioned in step (1) is a Y-type molecular sieve, and the properties of the Y-type molecular sieve are as follows: pore volume is 0.30~0.60cm³. 3 / g, specific surface area of ​​700-1000m² 2 / g, total acidity in infrared is 0.5-1.1 mmol / g, relative crystallinity is 90%-120%, SiO2 / Al2O3 molar ratio is 10-30, and cell parameter is 2.436-2.450 nm.

4. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The mass fraction of the aqueous solution of the heat-treated organic polymer in steps (1) and (3) is 0.5 wt% to 8.0 wt%.

5. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The mass fraction of the aqueous solution of the heat-treated organic polymer in steps (1) and (3) is 1.0 wt% to 5.0 wt%.

6. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (1), the ratio of the amount of the aqueous solution of the organic polymer added to the weight of the molecular sieve is 0.5 to 1.

5.

7. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The spherical forming process described in step (1) is one or both of extrusion spherical forming and roll forming.

8. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The organic acid in step (2) is selected from one or two of citric acid, acetic acid, lactic acid, malic acid, and tartaric acid.

9. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 8, characterized in that: The organic acid in step (2) is citric acid.

10. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The starch is one or more of the following: mung bean starch, tapioca starch, sweet potato starch, potato starch, wheat starch, water chestnut starch, lotus root starch, and corn starch; the cellulose ether is at least one of the following: methylcellulose, hydroxyethyl methylcellulose, carboxymethylcellulose, ethylcellulose, benzylcellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, cyanoethylcellulose, benzyl cyanoethylcellulose, carboxymethyl hydroxyethylcellulose, and phenylcellulose.

11. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The starch is corn starch and / or potato starch; the cellulose ether is methylcellulose.

12. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (2), the mass ratio of organic polymer to water is 0.1 to 0.5, and the mass ratio of organic polymer to organic acid is 1:0.1 to 1:

4.

13. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (2), the heating temperature is 30-50℃ and the treatment time is 2-6h.

14. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (2), the amount of organic polymer added is 5 wt% to 25 wt% of the dry basis mass of the boehmite powder.

15. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (2), the amount of organic polymer added is 10wt% to 20wt% of the dry basis mass of the boehmite powder.

16. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The properties of the pseudoboehmite powder mentioned in step (3) after calcination at 600℃ are as follows: specific surface area greater than 300m². 2 / g, with a pore volume of 0.5~0.9mL / g.

17. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The properties of the pseudoboehmite powder mentioned in step (3) after calcination at 600℃ are as follows: specific surface area is 330-370 m². 2 / g, with a pore volume of 0.55~0.85mL / g.

18. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The content of organic polymer in the pretreatment solution obtained in step (2) of step (3) is 10wt% to 20wt% of the dry basis mass of boehmite powder in step (3).

19. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The amount of the aqueous solution of the heated organic polymer added in step (3) is 0.1 to 1.0 of the mass of the pseudoboehmite powder.

20. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The first drying temperature in step (3) is 70-120℃; the first drying time is 8-12h.

21. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The first calcination in step (3) is carried out in the presence of an inert atmosphere, which is nitrogen and / or an inert gas; the first calcination temperature is 550-700℃ and the first calcination time is 1-5h.

22. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 21, characterized in that: The inert atmosphere is nitrogen.

23. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The particle size of the carrier mentioned in step (3) is 0.3 to 2.0 mm.

24. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The particle size of the carrier mentioned in step (3) is 0.5 to 1.8 mm.

25. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: In step (4), the group VIB metal compound is a molybdenum compound and / or a tungsten compound; the molybdenum compound is molybdenum oxide and / or ammonium heptamolybdate; the tungsten compound is ammonium metatungstate; the group VIII metal compound is a nickel compound and / or a cobalt compound; the nickel compound is basic nickel carbonate and / or nickel nitrate; and the cobalt compound is basic cobalt carbonate and / or cobalt nitrate.

26. The method for preparing the catalytic diesel hydrogenation catalyst according to claim 1, characterized in that: The second drying operation conditions in step (4) are as follows: the second drying temperature is 80-120℃ and the second drying time is 4-12h; the second calcination operation conditions in step (4) are as follows: the second calcination temperature is 400-600℃ and the second calcination time is 1-5h; the second calcination is carried out under air or oxygen atmosphere.

27. A catalytic diesel hydrogenation catalyst, wherein the catalytic diesel hydrogenation catalyst is obtained by the preparation method according to any one of claims 1-26.

28. The catalytic diesel hydrotreating catalyst according to claim 27, characterized in that: The catalytic diesel hydrotreating catalyst includes a support, an active metal component supported on the support, and an additive; the support is a composite support containing molecular sieves and alumina; the active metal component includes at least one metal element from Group VIB and at least one metal element from Group VIII, and the additive is phosphorus pentoxide.

29. The catalytic diesel hydrotreating catalyst according to claim 28, characterized in that: The support for the catalytic diesel hydrotreating catalyst is spherical with a core-shell structure, with molecular sieve as the core layer and alumina as the shell layer; based on the weight of the support, the molecular sieve content is 30% to 75% and the alumina content is 25% to 70%.

30. The catalytic diesel hydrotreating catalyst according to any one of claims 27-29, characterized in that: The properties of the catalytic diesel hydrotreating catalyst are as follows: specific surface area of ​​150–250 m². 2 / g, pore volume is 0.40~0.70mL / g, the proportion of mesopores with pore size of 10~50nm to the total pore volume is 50%~85%; total acid value is 0.40~0.70mmol / g, and lateral pressure strength is greater than 15N / mm.

31. The catalytic diesel hydrotreating catalyst according to any one of claims 27-29, characterized in that: Based on the final catalyst and calculated as oxides, the content of Group VIB metal components is 10 wt% to 25 wt%; the content of Group VIII metal components is 2 wt% to 7 wt%; and the content of the auxiliary agent phosphorus pentoxide is 2.0 wt% to 6.0 wt%.

32. A catalytic diesel hydrotreating process, wherein, under hydrotreating process conditions, catalytic diesel feedstock and hydrogen are contacted with the catalytic diesel hydrotreating catalyst described in any one of claims 27-31 to react.

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