Residual oil hydrodenitrification catalyst as well as preparation method and application thereof

Abstract

The invention discloses a residual oil hydrodenitrification catalyst as well as a preparation method and application thereof. The catalyst comprises a carrier, hydrogenation active metal components and an auxiliary agent, wherein the hydrogenation active metal components comprise tungsten sulfide, molybdenum sulfide and nickel sulfide; the catalyst is characterized by adopting a TEM-EDS method, and the atomic ratio of W to Mo at the center of an active phase is 2-60 times of the atomic ratio of W to Mo at the edge of the active phase. The catalyst is used in a residual oil hydrodenitrification process, and the hydrodenitrification activity and stability can be obviously improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogenation, and particularly relates to a hydrodenitrogenation catalyst, a preparation method thereof, and an application thereof in residue hydroprocessing. Background Art

[0002] At present, the active phases of the commonly used hydrogenation catalysts in the field of residue hydrogenation technology are mainly of two types: Ni-Mo-S type and Ni-W-S type. The former is mainly based on the MoS 2 crystal structure, and the latter is mainly based on the WS 2 crystal structure. Each of these two active phases has its own advantages. The active phase based on MoS 2 has the advantages of high surface sulfidation degree and relatively high hydrogenation activity, but the disadvantage is that MoS 2 itself has poor stability and is prone to aggregation. The WS 2 -based active phase has good stability and dispersibility, but the surface sulfidation degree is slightly lower, resulting in the hydrogenation activity of the Ni-W-S active phase being generally slightly lower than that of the Ni-Mo-W active phase. The modification and optimization of the active phase are also one of the key research points in this field.

[0003] CN107899586A discloses a residue hydrogenation catalyst containing rare earth. The catalyst is made from raw materials: diatomite, rare earth compound, iron oxide, methyl cellulose, activated carbon, magnesium oxide, silicon dioxide, zirconium dioxide, molybdenum dioxide. The residue hydrogenation catalyst containing rare earth can be used to process inferior residues such as asphalt and high-metal-content residues, extra-heavy oil, etc. This catalyst does not contain nickel element and cannot form a conventional active phase, and its hydrogenation performance is significantly insufficient.

[0004] CN1448486A discloses a novel catalyst for residue hydro-upgrading. The hydrogenation catalyst contains an oil agent colloid of molybdenum and / or tungsten, wherein the average particle size of MoS 2 and WS 2 is below 500 nanometers. This catalyst is suitable for the suspension bed hydrocracking process. When in use, the catalyst is first uniformly dispersed in heavy residue oil, and in the presence of hydrogen, the inferior heavy residue oil containing the catalyst undergoes a hydrogenation reaction. This highly dispersed catalyst has a good dispersion effect with the oil product, but due to the limitation of the overall low activity, its catalytic performance still needs to be further improved.

[0005] CN104096584A discloses a residue hydrogenation catalyst and a preparation method thereof. The catalyst uses an alumina and activated carbon kneaded body as the carrier, and the active components are Ni 2 P, MoO 3 and / or WO 3 , CoO and / or NiO. This catalyst has the ability to remove impurities such as desulfurization and decarbonization, but the low-valent phosphorus contained in the catalyst is prone to become PH during use.3 Gas loss leads to a decrease in catalyst stability. Summary of the Invention

[0006] In order to solve the contradiction that it is difficult to balance the activity and stability of residue hydrotreating catalysts in the prior art, the present invention provides a residue hydrodenitrogenation catalyst, a preparation method thereof, and an application. The catalyst of the present invention can significantly improve the hydrodenitrogenation activity and stability during the residue hydrodenitrogenation process.

[0007] In the first aspect of the present invention, a residue hydrodenitrogenation catalyst is provided, which includes a carrier, a hydrogenation active metal component, and an additive. The hydrogenation active metal component includes tungsten sulfide, molybdenum sulfide, and nickel sulfide; the additive is gallium. The catalyst is characterized by TEM-EDS method, and the ratio of W to Mo atoms at the active phase center is 2 - 60 times, preferably 5 - 40 times, that of W to Mo atoms at the active phase edge.

[0008] Furthermore, the catalyst is characterized by TEM-EDS method, and the ratio of W to Mo atoms at the active phase center is 2 - 60 times, preferably 5 - 40 times, that of W to Mo atoms at the active phase edge. For example, but not limited to, 2 times, 5 times, 10 times, 15 times, 20 times, 25 times, 30 times, 32 times, 35 times, 38 times, 40 times, 42 times, 45 times, 50 times, 55 times, 60 times, etc., and any value within the range formed by any two of these values.

[0009] Furthermore, the catalyst is characterized by TEM-EDS method. Tungsten sulfide is mainly distributed at the center of the active phase, and molybdenum sulfide is mainly distributed at the edge of the active phase. Among them, the active phase center is more than 3.0 nm away from the end point of the active phase edge, and the active phase edge refers to the area 0 - 2 nm away from the end point of the active phase edge.

[0010] Furthermore, the carrier can be a conventional carrier for residue hydrotreating catalysts, preferably a carrier for residue hydrodenitrogenation catalysts. The carrier is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxide, titanium-silicon composite oxide, etc., preferably alumina, and further preferably γ-alumina. In the carrier, conventional additives such as phosphorus, boron, etc. can also be contained. In the carrier, the mass content of the conventional additive in terms of elements accounts for less than 15%.

[0011] Furthermore, the properties of the carrier are as follows: the specific surface area is 160 - 380 m 2 / g, preferably 200 - 320 m 2 / g, the pore volume is 0.6 - 1.2 m 3 / g, preferably 0.7 - 1.1 m 3 / g.

[0012] Further, based on the mass of the catalyst, the mass content of the carrier is 55%-85%, preferably 60%-80%.

[0013] Further, based on the mass of the catalyst, the mass content of tungsten in terms of the element is 5%-15%, preferably 6%-12%, the mass content of molybdenum in terms of the element is 3%-15%, preferably 4%-12%, the mass content of nickel in terms of the element is 1%-5%, preferably 2%-4%, and the mass content of gallium in terms of the element is 0.3%-3.0%, preferably 0.5%-2.5%.

[0014] The second aspect of the present invention provides a method for preparing a residue hydrodenitrogenation catalyst, comprising:

[0015] (1) Impregnating a carrier with a tungsten-containing impregnating solution, drying, and calcining to obtain a catalyst intermediate containing tungsten oxide;

[0016] (2) Sulfurizing the catalyst intermediate obtained in step (1) to obtain a sulfided catalyst intermediate I;

[0017] (3) Mixing the sulfided catalyst intermediate I obtained in step (2) with an organic solution containing sulfur and organic molybdenum, and reacting in the presence of hydrogen to obtain a sulfided catalyst intermediate II;

[0018] (4) Mixing the sulfided catalyst intermediate II obtained in step (3) with an organic solution containing sulfur, organic nickel, and organic gallium, and reacting in the presence of hydrogen to obtain the catalyst.

[0019] Further, in step (1), the carrier can be a carrier for conventional residue hydrotreating catalysts, preferably a carrier for residue hydrodenitrogenation catalysts. The carrier is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxide, titanium-silicon composite oxide, etc., preferably alumina, and further preferably γ-alumina. In the carrier, conventional additives can also be contained, such as one or more of phosphorus, boron, etc. In the carrier, the mass content of the conventional additives in terms of the element accounts for less than 15%. Preferably, the properties of the carrier are as follows: the specific surface area is 160-380 m 2 / g, preferably 200-320 m 2 / g, the pore volume is 0.6-1.2 m 3 / g, preferably 0.7-1.1 m 3 / g.

[0020] Further, in step (1), in the tungsten-containing impregnating solution, the tungsten source can be a commonly used tungsten-containing compound, such as a soluble tungsten source, selected from at least one of ammonium tungstate, ammonium metatungstate, and ammonium paratungstate. In the tungsten-containing impregnating solution, the concentration of tungsten is 0.1-2.0 mol / L, preferably 0.2-1.5 mol / L.

[0021] Further, the impregnation in step (1) can be carried out by a conventional impregnation method, preferably the equal-volume impregnation method.

[0022] Further, in step (1), the drying conditions after impregnation are as follows: the drying temperature is 100 - 180 °C, preferably 120 - 160 °C, the drying time is 2 - 10 hours, preferably 4.0 - 8.0 hours; the calcination conditions are as follows: the calcination temperature is 350 - 550 °C, preferably 400 - 500 °C, the calcination time is 2.0 - 10.0 hours, preferably 4.0 - 8.0 hours.

[0023] In step (1), based on the mass of the catalyst intermediate, the mass content of tungsten in terms of the element is 6% - 18%, preferably 7% - 15%.

[0024] Further, in step (2), the sulfidation is carried out by a conventional sulfidation method in the art, and the present invention has no particular limitation. Preferably, the sulfidation is to fully sulfide the active metal tungsten.

[0025] Further, in step (2), the sulfidation is preferably wet sulfidation. The sulfidation solution used is composed of a sulfiding agent and a solvent. The sulfiding agent is one or more of carbon disulfide, dimethyl disulfide, diallyl trisulfide (DATS), and diallyl disulfide (DADS), and the solvent is one or more of cyclohexane, n-heptane, toluene, tetralin, decalin, industrial white oil, refined diesel, and refined aviation kerosene. The mass content of the sulfiding agent in the sulfidation solution is preferably 1% - 10%. Preferably, the wet sulfidation is carried out in the presence of hydrogen, and the catalyst intermediate obtained in step (1) is contacted with the sulfidation solution for a sulfidation reaction. Among them, the flow rate of the sulfidation solution is 0.5 - 5.0 ml / h·g 催化剂 , the sulfidation temperature is 280 - 380 °C, preferably 300 - 360 °C, the sulfidation time is 4.0 - 12.0 hours, preferably 6.0 - 10.0 hours, the hydrogen pressure is 1.0 - 10.0 MPa, preferably 2.0 - 8.0 MPa, and the flow rate of hydrogen is 10 - 30 Nml / min·g 催化剂。

[0026] Further, in step (3), the organic solution containing sulfur and organic molybdenum includes organic molybdenum, a sulfurizing agent, and an organic solvent. The organic molybdenum is one or more of molybdenum dialkyldithiophosphate, molybdenum dialkyldithiocarbamate, molybdenum dithiocarbamate, molybdenum naphthenate, molybdenum alkylsalicylate, and molybdenum carbonyl. The alkyl has 3 to 20 carbon atoms, preferably 4 to 15 carbon atoms. The sulfurizing agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide (DATS), and diallyl disulfide (DADS), and the organic solvent is at least one of n-hexadecane, hydrotreated diesel, refined aviation kerosene, industrial white oil, etc. In the organic solution containing sulfur and organic molybdenum, the mass content of organic molybdenum is 0.1% - 10.0%, preferably 0.5% - 8.0%, and the mass content of the sulfurizing agent is 0.5% - 5.0%, preferably 1.0% - 3.0%.

[0027] Further, in step (3), the mass ratio of the sulfurized catalyst intermediate I obtained in step (2) to the organic solution containing sulfur and organic molybdenum is 1:3 - 1:30, preferably 1:5 - 1:20.

[0028] Further, in step (3), the reaction process is divided into two stages: In the first stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 200 - 320 °C, preferably 220 - 280 °C, and the reaction time is 1.0 - 6.0 hours, preferably 2.0 - 4.0 hours; in the second stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 260 - 380 °C, preferably 280 - 360 °C, and the reaction time is 2.0 - 8.0 hours, preferably 3.0 - 6.0 hours.

[0029] Further, in step (4), the organic solution containing sulfur, organic nickel, and organic gallium includes a sulfurizing agent, organic nickel, organic gallium, and an organic solvent. The organic nickel is one or more of nickel benzoate, nickel acetylacetonate, nickel salicylate, nickel alkylphenylsalicylate, nickel citrate, nickel carbonyl, and nickel stearate. The alkyl has 3 to 20 carbon atoms, preferably 4 to 15 carbon atoms. The organic gallium is one or more of trimethylaminogallium, trimethylgallium, maltol gallium, gallium isopropoxide, triisopropylgallium, triethylgallium, ethoxygallium, and gallium acetylacetonate. The sulfurizing agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide (DATS), and diallyl disulfide (DADS). In the organic solution containing sulfur, organic nickel, and organic gallium, the mass content of organic nickel is 0.1% - 4.0%, preferably 0.2% - 3.0%, the mass content of organic gallium is 0.05% - 2.0%, preferably 0.1% - 1.0%, and the mass content of the sulfurizing agent is 0.5% - 5.0%, preferably 1.0% - 3.0%.

[0030] Further, in step (4), the mass ratio of the organic solution containing sulfur, organic nickel, and organic gallium to the sulfided catalyst intermediate II obtained in step (3) is 30:1 - 3:1, preferably 20:1 - 5:1.

[0031] Further, in step (4), the reaction process is divided into two stages: in the first stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 200 - 320 °C, preferably 220 - 280 °C, and the reaction time is 1.0 - 6.0 hours, preferably 2.0 - 4.0 hours; in the second stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 260 - 380 °C, preferably 280 - 360 °C, and the reaction time is 2.0 - 8.0 hours, preferably 3.0 - 6.0 hours.

[0032] Further, in the catalyst obtained in step (4), based on the mass of the catalyst, the mass content of tungsten in terms of the element is 5% - 15%, preferably 6% - 12%, the mass content of molybdenum in terms of the element is 3% - 15%, preferably 4% - 12%, the mass content of nickel in terms of the element is 1% - 5%, preferably 2% - 4%, and the mass content of gallium in terms of the element is 0.3% - 3.0%, preferably 0.5% - 2.5%.

[0033] Further, the catalyst is characterized by the TEM - EDS method, and the ratio of W to Mo atoms at the active phase center is 2 - 60 times, preferably 5 - 40 times, the ratio of W to Mo atoms at the active phase edge, such as but not limited to 2 times, 5 times, 10 times, 15 times, 20 times, 25 times, 30 times, 32 times, 35 times, 38 times, 40 times, 42 times, 45 times, 50 times, 55 times, 60 times, etc., and any value within the range formed by any two of these values.

[0034] Further, the catalyst is characterized by the TEM - EDS method, and tungsten sulfide is mainly distributed at the center of the active phase, and molybdenum sulfide is mainly distributed at the edge of the active phase. Among them, the active phase center is more than 3.0 nm from the end point of the active phase edge, and the active phase edge refers to the range from 0 - 2 nm from the end point of the active phase edge.

[0035] The third aspect of the present invention provides the catalyst prepared by the above method.

[0036] The fourth aspect of the present invention provides the application of the above catalyst in residue hydrotreating.

[0037] Further, in the above application, the catalyst is used as a hydrodenitrogenation catalyst.

[0038] Further, the residue feedstock can be at least one of atmospheric residue, vacuum residue, or deasphalted oil.

[0039] Further, the hydrotreating conditions are as follows: the reaction temperature is 300 - 450 °C, preferably 350 - 420 °C, the reaction pressure is 12 - 25 MPa, preferably 15 - 22 MPa, the hydrogen-to-oil volume ratio is 500 - 2000, and the liquid hourly space velocity is 0.05 - 0.6 h -1 , preferably 0.1 - 0.4 h -1 .

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] 1. Mo and W belong to the same group VIB elements. It has been found that the atomic radii of Mo and W are almost the same and the coordination situations are completely consistent. In the fully sulfided state, molybdenum and tungsten, as six-coordinate elements, can replace each other in any proportion inside the Ni-Mo(W)-S active phase while still maintaining the structural stability of the active phase. The present invention proposes a coated active phase with a WS 2 crystal structure as the inner core support, MoS 2 as the outer layer, and the surface is modified with low-coordination elements A (such as nickel and gallium). This active phase not only has the stability and dispersibility of WS 2 , but also has the high surface activity of MoS 2 . By further modifying the surface with low-coordination heteroatoms, the hydrodenitrogenation function of the catalyst can be further improved. Therefore, the catalyst of the present invention can not only take into account the advantages of the MoS 2 and WS 2 active phases, but also can significantly improve the activity and stability of the hydrodenitrogenation catalyst.

[0042] 2. During the preparation of the catalyst of the present invention, the supported tungsten species are first sulfided to form highly dispersed WS 2 platelets, which have a certain adsorption capacity and hydrogenation capacity for organic molybdenum, and can deposit molybdenum species in the form of metal on the edges of the WS 2 platelets. Then the molybdenum species are sulfided, and a coated active phase in which molybdenum sulfide species wrap tungsten sulfide species is formed. The active phase is then modified with low-coordination metals such as nickel and gallium. The catalyst prepared in this way can not only take into account the advantages of the MoS 2 and WS 2 active phases, but also can significantly improve the activity and stability of the hydrodenitrogenation catalyst. Detailed implementation manners

[0043] The present invention will be further described below in conjunction with embodiments, but it should be understood that the protection scope of the present invention is not limited by the embodiments. In the present invention, unless otherwise clearly stated, percentages and percentage contents are by mass.

[0044] In the present invention, the characterization of the active phase is obtained by the TEM-EDS (transmission electron microscopy - energy dispersive X-ray spectroscopy) method. The instrument model used is the JEOL JEM2200FS emission transmission electron microscope from Japan, equipped with a scanning transmission attachment and an X-ray energy spectrum attachment from EDAX Company in the United States. The accelerating voltage of the electron microscope is 200 kV. In the STEM mode, the condenser aperture is set to 2, and the spot size is 0.5 nm. The measurement process is as follows: The catalyst particles are ground, and the sample is prepared by the suspension method. 0.1 g of the catalyst sample is placed in a 2 mL container, ultrasonically dispersed with anhydrous ethanol, and the supernatant is taken. Two or three drops are taken with a dropper and dropped on a sample grid with a diameter of 3 mm. After drying, the sample to be measured is obtained. Then, the sample to be measured is observed and analyzed by TEM, and then combined with EDS to statistically analyze the content distribution of W and Mo in the active phase region observed by TEM. In the present invention, the region 0-2 nm from the edge endpoint of the active phase is defined as the active phase edge, and the position more than 3 nm from the edge is called the active phase center. Based on the peak area, the atomic ratio of W and Wo in the active phase center and edge is obtained. The present invention is obtained by averaging the data obtained by combining 40 TEM images with EDS analysis.

[0045] In the present invention, the specific surface area and pore volume are measured by using a Micromeritics TriStar II 2020 porosimeter from Micromeritics Instruments Corporation in the United States at -196 °C through N 2 adsorption and desorption to measure the pore structure characteristics of the catalytic material.

[0046] In the following examples and comparative examples of the present invention, the unmodified alumina support S-0 is prepared by the following method:

[0047] Weigh 2000.0 g of alumina dry gel powder, add 30.0 g of acetic acid, 25.0 g of citric acid, 30.0 g of sesbania powder, and 20.0 g of cellulose. After mixing evenly, add 1800.0 g of an aqueous solution containing 1.5% by mass of nitric acid, roll for 20.0 min, and extrude with a clover-shaped orifice plate with a diameter of 1.6 mm. After drying at 140 °C for 4.0 h, it is calcined at 600 °C for 4.0 h. The calcined support is denoted as S-0. The pore properties of the S-0 support are as follows: the specific surface area is 261 m 2 / g, and the pore volume is 0.92 cm 3 / g.

[0048] Example 1

[0049] Weigh 15.0 g of ammonium tungstate and dissolve it in 110 ml of deionized water to prepare a solution designated as WQ-1.

[0050] Weigh 100.0 g of support S-0, impregnate S-0 with WQ-1, let it stand for 12 hours, dry it at 120 °C for 4.0 h and then calcine it at 450 °C for 4.0 h. The obtained intermediate is denoted as OW-1.

[0051] Take 100.0 g of DMDS and 3000 g of cyclohexane to prepare a sulfiding solution, denoted as SQ-1.

[0052] Load OW-1 into a tubular reactor for sulfiding. The flow rate of SQ-1 introduced is 200 ml / h, the reaction temperature is 320 °C, control the hydrogen pressure in the reaction tube to be 4.0 MPa, after the reaction time of 6.0 hours, cool down, take out the intermediate, and obtain the sulfided catalyst intermediate I denoted as SW-1.

[0053] Weigh 22.0 g of molybdenum carbonyl and 20.0 g of carbon disulfide, dissolve them in 1000.0 g of industrial white oil, and the prepared solution is denoted as MQ-1.

[0054] Load SW-1 and MQ-1 into an autoclave together, seal it, stir, control the reaction pressure with hydrogen to be 6.0 MPa, heat the autoclave, control the reaction temperature to be 270 °C, the reaction time is 3.0 hours, then raise the temperature to 340 °C and react for another 6.0 hours. The obtained sulfided catalyst intermediate II is denoted as SMW-1.

[0055] Weigh 15.0 g of nickel acetylacetonate, 8.0 g of gallium acetylacetonate, and 20.0 g of carbon disulfide, dissolve them in 1000.0 g of refined diesel, and the prepared solution is denoted as NQ-1.

[0056] Load SMW-1 and NQ-1 into an autoclave together, seal it, stir, control the reaction pressure with hydrogen to be 6.0 MPa, heat the autoclave, control the reaction temperature to be 270 °C, the reaction time is 3.0 hours, then raise the temperature to 340 °C and react for another 6.0 hours to obtain the catalyst denoted as CAT-1.

[0057] Example 2

[0058] Weigh 15.0 g of ammonium metatungstate, dissolve it in 110 ml of deionized water, and the prepared solution is WQ-2.

[0059] Weigh 100.0 g of support S-0, impregnate S-0 with WQ-2, let it stand for 12 hours, dry it at 120 °C for 4.0 h and then calcine it at 450 °C for 4.0 h. The obtained intermediate is denoted as OW-2.

[0060] Take 100.0 g of carbon disulfide and 3000 g of cyclohexane to prepare a sulfiding solution, denoted as SQ-2.

[0061] Charge OW-2 into a tubular reactor for sulfidation. The flow rate of the sulfidation liquid SQ-2 is 200 ml / h, the reaction temperature is 320 °C, the hydrogen pressure in the reaction tube is controlled at 4.0 MPa, and after a reaction time of 6.0 hours, cool down and take out the intermediate to obtain the sulfided catalyst intermediate I denoted as SW-2.

[0062] Weigh 60.0 g of molybdenum dodecylsalicylate and 20.0 g of DMDS, dissolve them in 1000.0 g of industrial white oil, and the prepared solution is denoted as MQ-2.

[0063] Charge SW-2 and MQ-2 together into an autoclave, seal it, stir, control the reaction pressure with hydrogen at 5.0 MPa, heat the autoclave, control the reaction temperature at 250 °C, react for 4.0 hours, then raise the temperature to 320 °C and react for another 6.0 hours to obtain the sulfided catalyst intermediate II denoted as SMW-2.

[0064] Weigh 20.0 g of nickel benzoate, 6.0 g of triisopropylgallium, and 20.0 g of carbon disulfide, dissolve them in 1000.0 g of refined diesel, and the prepared solution is denoted as NQ-2.

[0065] Charge SMW-2 and NQ-2 together into an autoclave, seal it, stir, control the reaction pressure with hydrogen at 5.0 MPa, heat the autoclave, control the reaction temperature at 250 °C, react for 4.0 hours, then raise the temperature to 320 °C and react for another 6.0 hours to obtain the catalyst denoted as CAT-2.

[0066] Example 3

[0067] Weigh 15.0 g of ammonium paratungstate and dissolve it in 110 ml of deionized water to make a solution denoted as WQ-3.

[0068] Weigh 100.0 g of the support S-0, impregnate S-0 with WQ-3, let it stand for 12 hours, then dry it at 120 °C for 4.0 h and calcine it at 450 °C for 4.0 h to obtain the intermediate denoted as OW-3.

[0069] Take 150.0 g of diallyl disulfide and 3000 g of cyclohexane to prepare a sulfidation liquid denoted as SQ-3.

[0070] Charge OW-3 into a tubular reactor for sulfidation. The flow rate of the sulfidation liquid SQ-3 is 200 ml / h, the reaction temperature is 320 °C, the hydrogen pressure in the reaction tube is controlled at 4.0 MPa, and after a reaction time of 6.0 hours, cool down and take out the intermediate to obtain the sulfided catalyst intermediate I denoted as SW-3.

[0071] Weigh 30.0 g of molybdenum dithiocarbamate, 20.0 g of diallyl disulfide, dissolve them in 1000.0 g of industrial white oil, and the prepared solution is denoted as MQ-3.

[0072] Load SW-3 and MQ-3 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and the reaction time at 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours to obtain the sulfided catalyst intermediate II, denoted as SMW-3.

[0073] Weigh 30.0 g of nickel citrate monohydrate, 4.0 g of triethoxy gallium, and 20.0 g of diallyl disulfide, dissolve them in 1000.0 g of refined diesel, and the prepared solution is denoted as NQ-3.

[0074] Load SMW-3 and NQ-3 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and the reaction time at 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours. The obtained catalyst is denoted as CAT-3.

[0075] Comparative Example 1

[0076] Weigh 15.0 g of ammonium tungstate, 15.0 g of ammonium heptamolybdate tetrahydrate, 18.0 g of nickel nitrate hexahydrate, and 6.0 g of gallium nitrate hydrate, dissolve them in 110 ml of deionized water, and the prepared solution is denoted as DQ-1.

[0077] Weigh 100 g of S-0 support, impregnate it with DQ-1, let it stand for 12 hours, dry it at 120 °C for 4.0 hours, and then calcine it at 480 °C for 4.0 hours. The obtained catalyst is denoted as DOCT-1.

[0078] Put the catalyst DOCT-1 into a reaction tube, use a cyclohexane solution containing 4.0 wt% of DMDS as the sulfiding solution to sulfide the catalyst. During sulfiding, the hydrogen pressure is 6.0 MPa, the volume space velocity of the sulfiding solution is 1.0 h -1 , and the hydrogen-oil volume ratio is 300:1. After sulfiding at 350 °C for 8.0 hours, the obtained catalyst is denoted as DCT-1.

[0079] Comparative Example 2

[0080] Weigh 30.0 g of ammonium tungstate, dissolve it in 110 ml of deionized water, and the prepared solution is DWQ-2.

[0081] Weigh 100.0 g of support S-0, impregnate S-0 with DWQ-2, let it stand for 12 hours, dry it at 120 °C for 4.0 h, and then calcine it at 450 °C for 4.0 h. The obtained intermediate is denoted as DOW-2.

[0082] Weigh 15.0 g of nickel acetylacetonate and 8.0 g of gallium acetylacetonate, and dissolve them in 30.0 g of carbon disulfide and 1000.0 g of refined diesel oil. The prepared solution is denoted as DNQ-2.

[0083] Load DOW-2 and DNQ-2 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and react for 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours to obtain a catalyst denoted as DCT-2.

[0084] Comparative Example 3

[0085] Weigh 60.0 g of molybdenum dithiocarbamate and 50.0 g of diallyl disulfide, and dissolve them in 1000.0 g of industrial white oil. The prepared solution is denoted as DMQ-3.

[0086] Load 100.0 g of S-0 support and DMQ-3 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and react for 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours to obtain a sulfided catalyst intermediate denoted as DM-3.

[0087] Weigh 30.0 g of nickel citrate monohydrate, 4.0 g of triethoxy gallium, and 20.0 g of diallyl disulfide, and dissolve them in 1000.0 g of refined diesel oil. The prepared solution is denoted as DNQ-3.

[0088] Load DM-3 and DNQ-3 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and react for 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours to obtain a catalyst denoted as DCT-3.

[0089] Comparative Example 4

[0090] The preparation of the sulfided catalyst intermediate SMW-1 is the same as that in Example 1.

[0091] Weigh 15.0 g of nickel acetylacetonate and 20.0 g of carbon disulfide, and dissolve them in 1000.0 g of refined diesel oil. The prepared solution is denoted as DNQ-4.

[0092] Load SMW-1 and DNQ-4 into an autoclave together, seal it, stir, control the reaction pressure at 6.0 MPa with hydrogen, heat the autoclave, control the reaction temperature at 270 °C, and the reaction time at 3.0 hours. Then raise the temperature to 340 °C and react for another 6.0 hours to obtain a catalyst denoted as DCT-4.

[0093] Table 1 conducts elemental analysis on the catalysts obtained in each example

[0094] Catalyst Number W / wt% Mo / wt% Ni / wt% Ga / wt% CAT-1 7.9 6.2 2.6 1.1 CAT-2 8.4 5.9 2.9 1.2 CAT-3 8.2 5.9 2.4 1.3 DCT-1 7.8 6.2 2.8 1.2 DCT-2 17.2 0 2.5 1.1 DCT-3 0 11.6 2.7 1.4 DCT-4 7.9 6.2 2.7 0

[0095] Conduct TEM-EDS analysis on the catalyst. The ratio of the average W / Mo atomic ratio at the active phase center of the catalyst to the average W / Mo atomic ratio at the edge is shown in Table 2.

[0096] Table 2 Metal distribution on the active phase of the catalysts obtained in each example

[0097] Catalyst Number Ratio of W / Mo at the center to W / Mo at the edge CAT-1 39.5 CAT-2 25.5 CAT-3 24.0 DCT-1 1.07 DCT-2 - DCT-3 - DCT-4 35.6

[0098] Examples 4-6

[0099] Select vacuum residue as the raw material and adopt a fixed-bed hydrogenation process to conduct hydrogenation evaluation experiments on the catalysts obtained in Examples 1-3 above. The properties of the vacuum residue are shown in Table 3.

[0100] Table 3 Properties of vacuum residue

[0101] Item Value Item Value <![CDATA[Density / g·cm -3 > 0.982 Nitrogen content, μg / g 2745 Vanadium + nickel content, μg / g 40.48 H / C atomic ratio 1.54 Sulfur content, μg / g 33692 Conradson carbon residue, % 17.7

[0102] Load a hydrogenation protective agent (FZC-100B) and a hydrodemetallization catalyst (FZC-204A) in front of the above catalyst. The filling volume ratio of the protective agent, hydrodemetallization catalyst, and the catalyst obtained in the example is 1:2:4. The operating conditions are: reaction temperature 390 °C, reaction pressure 20.0 MPa, hydrogen-oil volume ratio 1500:1, and liquid hourly space velocity 0.15 h -1 -1. After 1000 h of reaction evaluation, analyze the nitrogen content, carbon residue value, and sulfur content in the fraction of the hydrogenated product oil with a boiling point not lower than 300 °C. The results are shown in Table 4.

[0103] Comparative Examples 5-8

[0104] The vacuum residue (see Table 3) was selected as the raw material, and the fixed-bed process was adopted to evaluate the activity of the catalysts obtained in Comparative Examples 1-4. A hydrogenation protective agent (FZC-100B) and a hydrodemetallization catalyst (FZC-204A) were loaded in front of the above-mentioned catalysts. The loading volume ratio of the protective agent, the hydrodemetallization catalyst, and the catalyst obtained in the comparative example was 1:2:4. The operating conditions were: reaction temperature 390 °C, reaction pressure 20.0 MPa, hydrogen-oil volume ratio 1500:1, and liquid hourly space velocity 0.15 h -1 . After 1000 h of reaction evaluation, the nitrogen content, carbon residue value, and sulfur content in the fraction of the hydrogenated product oil not lower than 300 °C were analyzed, and the results are shown in Table 4.

[0105] Table 4 Properties of the fixed-bed hydrogenated product oil obtained in each example

[0106] Number Catalyst Nitrogen content, μg / g Conradson carbon residue, % Sulfur content, μg / g Example 4 Cat-1 251 3.9 1650 Example 5 Cat-2 278 3.7 1566 Example 6 Cat-3 265 3.7 1473 Comparative Example 5 DCT-1 852 6.4 2391 Comparative Example 6 DCT-2 765 6.2 2108 Comparative Example 7 DCT-3 799 6.9 2547 Comparative Example 8 DCT-4 558 4.2 1859

[0107] It can be seen from the evaluation results in Table 4 that the catalyst of the present invention has good hydrodenitrogenation, hydrodesulfurization, and hydrodearbonization activities during the residue oil hydrotreating process.

Claims

1. A residue hydrodenitrogenation catalyst, comprising a support, a hydrogenation active metal component, and an auxiliary agent, wherein the hydrogenation active metal component includes tungsten sulfide, molybdenum sulfide, and nickel sulfide; the auxiliary agent is gallium, and the catalyst is characterized by TEM-EDS method, and the atomic ratio of W to Mo at the active phase center is 2-60 times, preferably 5-40 times, that of W to Mo at the active phase edge.

2. The catalyst according to claim 1, characterized in that, the support is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxide, and titanium-silicon composite oxide, preferably alumina; optionally, the support further contains a conventional auxiliary agent, preferably one or more of phosphorus and boron, and in the support, the mass content of the conventional auxiliary agent calculated as an element accounts for less than 15%.

3. The catalyst according to claim 1 or 2, characterized in that, The properties of the carrier are as follows: the specific surface area is 160 - 380 m 2 / g, preferably 200 - 320 m 2 / g, the pore volume is 0.6 - 1.2 m 3 / g, preferably 0.7 - 1.1 m 3 / g.

4. The catalyst according to claim 1 or 2, characterized in that, Based on the mass of the catalyst, the mass content of the support is 55%-85%, preferably 60%-80%.

5. The catalyst according to claim 1 or 4, characterized in that, Based on the mass of the catalyst, the mass content of tungsten calculated as an element is 5%-15%, preferably 6%-12%, the mass content of molybdenum calculated as an element is 3%-15%, preferably 4%-12%, the mass content of nickel calculated as an element is 1%-5%, preferably 2%-4%, and the mass content of gallium calculated as an element is 0.3%-3.0%, preferably 0.5%-2.5%.

6. A preparation method of a residue hydrodenitrogenation catalyst, comprising: (1) Impregnating the support with a tungsten-containing impregnating solution, drying, and calcining to obtain a catalyst intermediate containing tungsten oxide; (2) Sulfurizing the catalyst intermediate obtained in step (1) to obtain a sulfided catalyst intermediate I; (3) Mixing the sulfided catalyst intermediate I obtained in step (2) with an organic solution containing sulfur and organic molybdenum, and reacting in the presence of hydrogen to obtain a sulfided catalyst intermediate II; (4) Mixing the sulfided catalyst intermediate II obtained in step (3) with an organic solution containing sulfur, organic nickel, and organic gallium, and reacting in the presence of hydrogen to obtain the catalyst.

7. The preparation method according to claim 6, characterized in that, in step (1), the support is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxide, and titanium-silicon composite oxide, preferably alumina; optionally, in the support, there is also a conventional auxiliary agent, such as one or more of phosphorus and boron, and in the support, the mass content of the conventional auxiliary agent calculated as an element accounts for less than 15%; Preferably, the properties of the carrier are as follows: the specific surface area is 160 - 380 m 2 / g, preferably 200 - 320 m 2 / g, the pore volume is 0.6 - 1.2 m 3 / g, preferably 0.7 - 1.1 m 3 / g.

8. The preparation method according to claim 6, characterized in that, in step (1), based on the mass of the catalyst intermediate, the mass content of tungsten calculated as an element is 6%-18%, preferably 7%-15%.

9. The preparation method according to claim 6, characterized in that, in step (3), the organic solution containing sulfur and organic molybdenum includes organic molybdenum, a sulfurizing agent, and an organic solvent; Preferably, the organic molybdenum is one or more of molybdenum dialkyldithiophosphate, molybdenum dialkyldithiocarbamate, molybdenum dithiocarbamate, molybdenum naphthenate, molybdenum alkylsalicylate, and molybdenum carbonyl. The number of carbon atoms in the alkyl group is preferably 3-20, more preferably 4-15; and / or, the sulfurizing agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide, and diallyl disulfide; and / or, the organic solvent is at least one of n-hexadecane, hydrotreated diesel, refined aviation kerosene, and industrial white oil; Preferably, in the organic solution containing sulfur and organic molybdenum, the mass content of organic molybdenum is 0.1%-10.0%, preferably 0.5%-8.0%; and / or, the mass content of the sulfurizing agent is 0.5%-5.0%, preferably 1.0%-3.0%.

10. According to the preparation method described in claim 6, It is characterized in that In step (3), the mass ratio of the sulfurized catalyst intermediate I obtained in step (2) to the organic solution containing sulfur and organic molybdenum is 1:3 - 1:30, preferably 1:5 - 1:

20.

11. According to the preparation method described in claim 6, It is characterized in that In step (3), the reaction process is divided into two stages: In the first stage, the pressure is controlled at 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 200 - 320 °C, preferably 220 - 280 °C, and the reaction time is 1.0 - 6.0 hours, preferably 2.0 - 4.0 hours; in the second stage, the pressure is controlled at 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 260 - 380 °C, preferably 280 - 360 °C, and the reaction time is 2.0 - 8.0 hours, preferably 3.0 - 6.0 hours.

12. According to the preparation method described in claim 6, It is characterized in that In step (4), the organic solution containing sulfur, organic nickel, and organic gallium includes a sulfurizing agent, organic nickel, organic gallium, and an organic solvent; Preferably, the organic nickel is one or more of nickel benzoate, nickel acetylacetonate, nickel salicylate, nickel alkylphenylsalicylate, nickel citrate, nickel carbonyl, and nickel stearate. The number of carbon atoms in the alkyl group is preferably 3-20, more preferably 4-15; and / or, the organic gallium is one or more of trimethylaminogallium, trimethylgallium, maltol gallium, gallium isopropoxide, triisopropylgallium, triethylgallium, ethoxygallium, and gallium acetylacetonate; and / or, the sulfurizing agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide, and diallyl disulfide; Preferably, in the organic solution containing sulfur, organic nickel, and organic gallium, the mass content of organic nickel is 0.1%-4.0%, preferably 0.2%-3.0%; and / or, the mass content of organic gallium is 0.05%-2.0%, preferably 0.1%-1.0%; and / or, the mass content of the sulfurizing agent is 0.5%-5.0%, preferably 1.0%-3.0%.

13. According to the preparation method described in claim 6, It is characterized in that In step (4), the mass ratio of the organic solution containing sulfur, organic nickel and organic gallium to the sulfided catalyst intermediate II obtained in step (3) is 30:1 - 3:1, preferably 20:1 - 5:

1.

14. According to the preparation method described in claim 6, it is characterized in that in step (4), the reaction process is divided into two stages: in the first stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 200 - 320 °C, preferably 220 - 280 °C, and the reaction time is 1.0 - 6.0 hours, preferably 2.0 - 4.0 hours; in the second stage, the pressure is controlled to be 0.5 - 10.0 MPa, preferably 1.0 - 6.0 MPa, the temperature is 260 - 380 °C, preferably 280 - 360 °C, and the reaction time is 2.0 - 8.0 hours, preferably 3.0 - 6.0 hours.

15. According to the preparation method described in claim 6, it is characterized in that in step (4), for the obtained catalyst, based on the mass of the catalyst, the mass content of tungsten in terms of the element is 5% - 15%, preferably 6% - 12%, the mass content of molybdenum in terms of the element is 3% - 15%, preferably 4% - 12%, the mass content of nickel in terms of the element is 1% - 5%, preferably 2% - 4%, and the mass content of gallium in terms of the element is 0.3% - 3.0%, preferably 0.5% - 2.5%.

16. A catalyst prepared by the method according to any one of claims 6 - 15.

17. The application of the catalyst according to any one of claims 1 - 5 or the catalyst according to claim 16 in residue hydrotreating.