Residue hydrodenitrogenation catalyst, method of making and use

Abstract

The application discloses a residual oil hydrodenitrogenation catalyst, a preparation method and application thereof. The catalyst comprises a carrier, a hydrogenation active metal component and an additive, wherein the hydrogenation active metal component comprises tungsten sulfide, molybdenum sulfide and nickel sulfide; the additive is gallium; the catalyst is characterized by a TEM-EDS method, and the atomic ratio of W to Mo in the active phase center is 2-60 times of the atomic ratio of W to Mo in the active phase edge. The catalyst can obviously improve the hydrodenitrogenation activity and stability in the process of residual oil hydrodenitrogenation.

Description

Technical Field

[0001] This invention belongs to the field of hydrogenation technology, and specifically relates to a hydrogenation denitrification catalyst and its preparation method, as well as its application in the hydrogenation treatment of residual oil. Background Technology

[0002] Currently, the active phases of commonly used hydrogenation catalysts in the field of residue hydrotreating technology are mainly of two types: Ni-Mo-S and Ni-WS. The former is dominated by a MoS2 crystal structure, while the latter is dominated by a WS2 crystal structure. Each of these active phases has its advantages. The advantage of the MoS2-dominated active phase is its high surface sulfidation degree and relatively high hydrogenation activity. The disadvantage is that MoS2 itself has poor stability and is prone to aggregation. The WS2-dominated active phase has good stability and dispersibility, but its surface sulfidation degree is slightly lower, resulting in the hydrogenation activity of the Ni-WS active phase being generally slightly lower than that of the Ni-Mo-W active phase. Modification and optimization of the active phase is also one of the key research focuses in this field.

[0003] CN107899586A discloses a rare-earth-containing residue oil hydrotreating catalyst. The catalyst is made from the following raw materials: diatomaceous earth, rare earth compounds, iron oxide, methylcellulose, activated carbon, magnesium oxide, silicon dioxide, zirconium oxide, and molybdenum dioxide. This rare-earth-containing residue oil hydrotreating catalyst can be used to treat asphalt and low-quality residue oil with high metal content, as well as extra-heavy oil. However, this catalyst does not contain nickel and cannot form a conventional active phase, resulting in significantly insufficient hydrotreating performance.

[0004] CN1448486A discloses a novel catalyst for the hydrotreating of residual oil. This hydrotreating catalyst contains a molybdenum and / or tungsten-containing oil colloid, wherein the average particle size of MoS2 and WS2 is below 500 nanometers. This catalyst is suitable for use in slurry-bed hydrocracking processes. In use, the catalyst is first uniformly dispersed in heavy residual oil, and then, in the presence of hydrogen, the low-quality heavy residual oil containing the catalyst undergoes a hydrotreating reaction. This highly dispersible catalyst exhibits excellent dispersion with the oil, but its catalytic performance still needs further improvement due to its relatively low overall activity.

[0005] CN104096584A discloses a residue oil hydrotreating catalyst and its preparation method. The catalyst uses an alumina and activated carbon mixture as a support, and the active components are Ni₂P, MoO₃ and / or WO₃, CoO and / or NiO. This catalyst has the ability to remove impurities such as sulfur dioxide and residual carbon; however, the low-valence phosphorus contained in the catalyst is easily converted into PH₃ gas and lost during use, leading to a decrease in catalyst stability. Summary of the Invention

[0006] To address the inherent challenge of balancing activity and stability in existing residue hydrotreating catalysts, this invention provides a residue hydrodenitrogenation catalyst, its preparation method, and its application. The catalyst of this invention, when used in the residue hydrodenitrogenation process, significantly improves both hydrodenitrogenation activity and stability.

[0007] The first aspect of the present invention provides a hydrodenitrification catalyst for residual oil, comprising a support, a hydrotreating active metal component, and an additive, wherein the hydrotreating active metal component comprises tungsten sulfide, molybdenum sulfide, and nickel sulfide; the additive is gallium; 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 that at the active phase edge, preferably 5-40 times.

[0008] Furthermore, the catalyst is characterized by TEM-EDS, and the ratio of W to Mo atoms at the active phase center is 2-60 times that at the active phase edge, preferably 5-40 times, 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 was characterized using TEM-EDS. Tungsten sulfide was mainly distributed at the center of the active phase, while molybdenum sulfide was mainly distributed at the edge of the active phase. The center of the active phase is defined as a location at least 3.0 nm from the endpoint of the active phase edge, while the active phase edge is defined as a location 0-2 nm from the endpoint of the active phase edge.

[0010] Furthermore, the support can be a conventional support for residue hydrotreating catalysts, preferably a support for residue hydrodenitrification catalysts. The support is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxides, and titanium-silicon composite oxides, preferably alumina, and more preferably γ-alumina. The support may also contain one or more conventional additives, such as phosphorus and boron. The conventional additives in the support, by mass, account for less than 15% of the total content (based on elemental composition).

[0011] Furthermore, the carrier has the following properties: specific surface area of ​​160-380 m². 2 / g, preferably 200-320m 2 / g, pore volume 0.6-1.2m 3 / g, preferably 0.7-1.1m 3 / g.

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

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

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

[0015] (1) Impregnate the support with a tungsten-containing impregnation solution, dry and calcine to obtain a catalyst intermediate containing tungsten oxide;

[0016] (2) Sulfide the catalyst intermediate from step (1) to obtain sulfidated catalyst intermediate I;

[0017] (3) The sulfidated catalyst intermediate I obtained in step (2) is mixed with an organic solution containing sulfur and organic molybdenum and reacted in the presence of hydrogen to obtain the sulfidated catalyst intermediate II.

[0018] (4) The sulfidated catalyst intermediate II obtained in step (3) is mixed with an organic solution containing sulfur, organonitrile and organogallium, and reacted in the presence of hydrogen to obtain the catalyst.

[0019] Further, in step (1), the support can be a conventional support for residue hydrotreating catalysts, preferably a support for residue hydrodenitrification catalysts. The support is selected from at least one of alumina, silica, amorphous silica-alumina, titanium-aluminum composite oxides, and titanium-silicon composite oxides, preferably alumina, and more preferably γ-alumina. The support may also contain conventional additives, such as one or more of phosphorus and boron. The conventional additives in the support, by mass, account for less than 15% of the total mass. Preferably, the support has the following properties: a specific surface area of ​​160-380 m². 2 / g, preferably 200-320m 2 / g, pore volume 0.6-1.2m 3 / g, preferably 0.7-1.1m 3 / g.

[0020] Further, in step (1), the tungsten source in the tungsten-containing impregnation solution 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. The concentration of tungsten in the tungsten-containing impregnation solution is 0.1-2.0 mol / L, preferably 0.2-1.5 mol / L.

[0021] Furthermore, the impregnation in step (1) can be carried out using conventional impregnation methods, preferably equal-volume impregnation methods.

[0022] Further, in step (1), the drying conditions after impregnation are as follows: the drying temperature is 100-180℃, preferably 120-160℃, and 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℃, preferably 400-500℃, and 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, calculated as an element, is 6%-18%, preferably 7%-15%.

[0024] Furthermore, in step (2), the sulfidation is carried out using conventional sulfidation methods in the art. The present invention does not have any particular limitations, but preferably the sulfidation is to fully sulfidate the active metal tungsten.

[0025] Further, in step (2), the sulfidation is preferably wet sulfidation. The sulfidation liquid used consists 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). The solvent is one or more of cyclohexane, n-heptane, toluene, tetrahydronaphthalene, decahydronaphthalene, industrial white oil, refined diesel oil, and refined jet fuel. The mass content of the sulfiding agent in the sulfidation liquid is preferably 1%-10%. Preferably, the wet sulfidation is carried out in the presence of hydrogen, where the catalyst intermediate obtained in step (1) is contacted with the sulfidation liquid to carry out the sulfidation reaction, wherein the flow rate of the sulfidation liquid is 0.5-5.0 ml / h·g. 催化剂 The vulcanization temperature is 280-380℃, preferably 300-360℃; the vulcanization 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 hydrogen flow rate 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 vulcanizing agent, and an organic solvent. The organic molybdenum is one or more of dialkyl dithiophosphate molybdenum, dialkyl dithiocarbamate molybdenum, dithiocarbamate molybdenum, naphthenic acid molybdenum, alkyl salicylate molybdenum, and carbonyl molybdenum. The alkyl group has 3-20 carbon atoms, preferably 4-15. The vulcanizing 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 jet fuel, and industrial white oil. 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 vulcanizing agent is 0.5%-5.0%, preferably 1.0%-3.0%.

[0027] Further, in step (3), the mass ratio of the sulfidated 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 at 0.5-10.0 MPa, preferably 1.0-6.0 MPa, the temperature is 200-320℃, preferably 220-280℃, 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℃, preferably 280-360℃, 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, organonitrile, and organogallium includes a sulfiding agent, organonitrile, organogallium, and an organic solvent. The organonitrile is one or more of nickel benzoate, nickel acetylacetonate, nickel salicylate, alkylphenyl salicylate, nickel citrate, nickel carbonyl, and nickel stearate. The alkyl group has 3-20 carbon atoms, preferably 4-15. The organogallium is one or more of trimethylaminogallium, trimethylgallium, maltol gallium, isopropoxide gallium, triisopropylgallium, triethylgallium, ethoxygallium, and gallium acetylacetonate. The sulfiding agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide (DATS), and diallyl disulfide (DADS). In the organic solution containing sulfur, organonitrile, and organogallium, the organonitrile has a mass content of 0.1%-4.0%, preferably 0.2%-3.0%, the organogallium has a mass content of 0.05%-2.0%, preferably 0.1%-1.0%, and the sulfiding agent has a mass content of 0.5%-5.0%, preferably 1.0%-3.0%.

[0030] Further, in step (4), the mass ratio of the organic solution containing sulfur, organonitrile and organogallium to the sulfide 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 at 0.5-10.0 MPa, preferably 1.0-6.0 MPa, the temperature is 200-320℃, preferably 220-280℃, 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℃, preferably 280-360℃, and the reaction time is 2.0-8.0 hours, preferably 3.0-6.0 hours.

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

[0033] Furthermore, the catalyst is characterized by TEM-EDS, and the ratio of W to Mo atoms at the active phase center is 2-60 times that at the active phase edge, preferably 5-40 times, 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.

[0034] Furthermore, the catalyst was characterized using TEM-EDS. Tungsten sulfide was mainly distributed at the center of the active phase, while molybdenum sulfide was mainly distributed at the edge of the active phase. The center of the active phase is defined as a location at least 3.0 nm from the endpoint of the active phase edge, while the active phase edge is defined as a location 0-2 nm from the endpoint of the active phase edge.

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

[0036] The fourth aspect of this invention provides the application of the above-mentioned catalyst in the hydrotreating of residual oil.

[0037] Furthermore, in the aforementioned application, the catalyst is used as a hydrodenitrification catalyst.

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

[0039] Furthermore, the hydrogenation treatment conditions are as follows: reaction temperature 300-450℃, preferably 350-420℃; reaction pressure 12-25MPa, preferably 15-22MPa; hydrogen-to-oil volume ratio 500-2000; and liquid hourly space velocity 0.05-0.6h⁻¹. -1 Preferably 0.1-0.4h -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. Studies have found that Mo and W have almost the same atomic radius and completely identical coordination. Under fully sulfided conditions, molybdenum and tungsten, as six-coordinate elements, can substitute for each other in any proportion within the Ni-Mo(W)-S active phase while maintaining the structural stability of the active phase. This invention proposes a coated active phase with a WS2 crystal structure as the core support, MoS2 as the outer layer, and a surface modified with low-coordinate element A (such as nickel or gallium). This active phase possesses both the stability and dispersibility of WS2 and the high surface activity of MoS2. Further surface modification with low-coordinate heteroatoms can further enhance the hydrodenitrification function of the catalyst. Therefore, the catalyst of this invention not only combines the advantages of both MoS2 and WS2 active phases but also significantly improves the activity and stability of the hydrodenitrification catalyst.

[0042] 2. In the catalyst preparation process of this invention, the supported tungsten species are first sulfided to form highly dispersed WS2 lamellar crystals, which have a certain adsorption and hydrogenation capacity for organomolybdenum. This allows molybdenum species to be deposited in metallic form at the edges of the WS2 lamellar crystals. Further sulfidation of the molybdenum species results in a coated active phase where molybdenum sulfide species encapsulate tungsten sulfide species. The active phase is then modified with low-coordination metals such as nickel and gallium. The catalyst prepared in this way not only combines the advantages of both MoS2 and WS2 active phases but also significantly improves the activity and stability of the hydrodenitrification catalyst. Detailed Implementation

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

[0044] In this invention, the active phase is characterized by TEM-EDS (Transmission Electron Microscopy-Energy Dispersion X-ray Spectroscopy). The instrument used is a JEOL JEM2200FS emission transmission electron microscope (Japan), equipped with a scanning transmission accessory and an EDAX X-ray energy dispersion accessory (USA). The electron microscope accelerating voltage is 200 kV, in STEM mode, the condenser aperture is set to 2, and the spectrophotometer size is 0.5 nm. The measurement process is as follows: The catalyst particles are ground and the sample is prepared by suspension method. 0.1 g of the catalyst sample is placed in a 2 mL container and ultrasonically dispersed with anhydrous ethanol. The supernatant is collected, and two to three drops are taken with a dropper and dropped onto a 3 mm diameter sample grid. After drying, the sample to be tested is obtained. Then, the sample to be tested is observed and analyzed by TEM. Then, the content distribution of W and Mo in the active phase region observed by TEM is statistically analyzed in combination with EDS. In this invention, the active phase edge is defined as 0-2 nm away from the edge endpoint, and the active phase center is defined as the position more than 3 nm away from the edge. The atomic ratio of W to Wo distributed in the center and edge of the active phase is obtained based on peak area. This invention uses the average value of data obtained from 40 TEM images combined with EDS analysis.

[0045] In this invention, the specific surface area and pore volume are measured using a Micromeritics TriStar II 2020 porosimeter at -196°C by N2 adsorption and desorption to determine the pore structure characteristics of the catalytic material.

[0046] The unmodified alumina support S-0 used in the following embodiments and comparative examples of this invention was prepared by the following method:

[0047] Weigh 2000.0g of alumina dry adhesive powder, add 30.0g of acetic acid, 25.0g of citric acid, 30.0g of guar gum powder, and 20.0g of cellulose, mix well, then add 1800.0g of an aqueous solution containing 1.5% nitric acid. After rolling for 20.0min, extrude the mixture using a 1.6mm diameter clover-shaped perforated plate. Dry at 140℃ for 4.0h, then calcine at 600℃ for 4.0h. The calcined carrier is designated S-0. The pore properties of the S-0 carrier are as follows: specific surface area is 261m². 2 / g, pore volume 0.92cm 3 / g.

[0048] Example 1

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

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

[0051] Prepare a sulfidation solution by mixing 100.0g of DMDS with 3000g of cyclohexane, denoted as SQ-1.

[0052] OW-1 was loaded into a tubular reactor for sulfidation. The flow rate of SQ-1 was 200 ml / h, the reaction temperature was 320℃, the hydrogen pressure in the reaction tube was controlled at 4.0 MPa, and the reaction time was 6.0 hours. After cooling, the intermediate was taken out, and the sulfidated catalyst intermediate I was obtained, which was denoted as SW-1.

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

[0054] SW-1 and MQ-1 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was carried out for another 6.0 hours. The resulting sulfidated catalyst intermediate II was designated as SMW-1.

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

[0056] SMW-1 and NQ-1 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was continued for another 6.0 hours to obtain the catalyst, which was designated CAT-1.

[0057] Example 2

[0058] Weigh 15.0g of ammonium metatungstate and dissolve it in 110ml of deionized water to prepare solution WQ-2.

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

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

[0061] OW-2 was loaded into a tubular reactor for sulfidation. The flow rate of the sulfidation liquid SQ-2 was 200 ml / h, the reaction temperature was 320℃, the hydrogen pressure in the reaction tube was controlled at 4.0 MPa, and the reaction time was 6.0 hours. After cooling, the intermediate was taken out, and the sulfidated catalyst intermediate I was obtained, which was denoted as SW-2.

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

[0063] SW-2 and MQ-2 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 5.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 250℃ for 4.0 hours. Then the temperature was increased to 320℃ and the reaction was carried out for another 6.0 hours to obtain the sulfidated catalyst intermediate II, denoted as SMW-2.

[0064] Weigh 20.0g of nickel benzoate, 6.0g of triisopropyl gallium, and 20.0g of carbon disulfide, and dissolve them in 1000.0g of refined diesel oil. The resulting solution is denoted as NQ-2.

[0065] SMW-2 and NQ-2 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 5.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 250℃ for 4.0 hours. Then the temperature was increased to 320℃ and the reaction was continued for 6.0 hours to obtain the catalyst, which was designated as CAT-2.

[0066] Example 3

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

[0068] Weigh 100.0g of carrier S-0, impregnate S-0 with WQ-3, let stand for 12 hours, dry at 120℃ for 4.0h and calcine at 450℃ for 4.0h. The intermediate obtained is denoted as OW-3.

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

[0070] OW-3 was loaded into a tubular reactor for sulfidation. The flow rate of the sulfidation liquid SQ-3 was 200 ml / h, the reaction temperature was 320℃, the hydrogen pressure in the reaction tube was controlled at 4.0 MPa, and the reaction time was 6.0 hours. After cooling, the intermediate was taken out, and the sulfidated catalyst intermediate I was obtained, which was denoted as SW-3.

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

[0072] SW-3 and MQ-3 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was carried out for another 6.0 hours to obtain the sulfidated catalyst intermediate II, denoted as SMW-3.

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

[0074] SMW-3 and NQ-3 were loaded together into a high-pressure reactor, sealed, and stirred. The reaction pressure was controlled at 6.0 MPa using hydrogen gas. The reactor was heated to 270°C for 3.0 hours, and then the temperature was increased to 340°C for another 6.0 hours. The resulting catalyst was designated CAT-3.

[0075] Comparative Example 1

[0076] Weigh out 15.0g of ammonium tungstate, 15.0g of ammonium heptamolybdate tetrahydrate, 18.0g of nickel nitrate hexahydrate, and 6.0g of gallium nitrate hydrate, dissolve them in 110ml of deionized water, and prepare a solution labeled DQ-1.

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

[0078] The catalyst DOCT-1 was placed in a reaction tube, and a cyclohexane solution containing 4.0 wt% DMDS was used as the sulfiding liquid to sulfide the catalyst. During sulfidation, the hydrogen pressure was 6.0 MPa and the liquid hourly space velocity (LHSV) was 1.0 h⁻¹. -1 The catalyst obtained after sulfidation at 350°C for 8.0 hours with a hydrogen-to-oil volume ratio of 300:1 is designated as DCT-1.

[0079] Comparative Example 2

[0080] Weigh 30.0g of ammonium tungstate and dissolve it in 110ml of deionized water to prepare a solution called DWQ-2.

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

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

[0083] DOW-2 and DNQ-2 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was carried out for another 6.0 hours to obtain the catalyst, which was designated as DCT-2.

[0084] Comparative Example 3

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

[0086] 100.0 g of S-0 support and DMQ-3 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa using hydrogen gas. The reactor was heated to 270 °C for 3.0 hours, and then the temperature was increased to 340 °C for another 6.0 hours. The resulting sulfidized catalyst intermediate was designated DM-3.

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

[0088] DM-3 and DNQ-3 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was carried out for another 6.0 hours to obtain the catalyst, which was designated as DCT-3.

[0089] Comparative Example 4

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

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

[0092] SMW-1 and DNQ-4 were loaded into a high-pressure reactor, sealed, stirred, and the reaction pressure was controlled at 6.0 MPa with hydrogen. The reactor was heated and the reaction temperature was controlled at 270℃ for 3.0 hours. Then the temperature was increased to 340℃ and the reaction was carried out for another 6.0 hours to obtain the catalyst, which was designated as DCT-4.

[0093] Table 1 shows the elemental analysis of the catalysts obtained in each example.

[0094] 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] TEM-EDS analysis was performed on the catalyst, and the ratio of the average W / Mo atomic ratio at the center of the active phase to that 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] 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] Vacuum residue was selected as feedstock, and a fixed-bed hydrotreating process was used to evaluate the hydrogenation of the catalysts obtained in Examples 1-3. The properties of the vacuum residue are shown in Table 3.

[0100] Table 3 Properties of vacuum residue

[0101] <![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 Kang's carbon residue, % 17.7

[0102] A hydroprotective agent (FZC-100B) and a hydrodemetallization catalyst (FZC-204A) were loaded before the aforementioned catalyst. The volume ratio of the protective agent, the hydrodemetallization catalyst, and the catalyst obtained in the examples was 1:2:4. The operating conditions were: reaction temperature 390°C, reaction pressure 20.0 MPa, hydrogen-to-oil volume ratio 1500:1, and liquid hourly space velocity (LHSV) 0.15 h⁻¹. -1 After 1000 hours of reaction evaluation, the nitrogen content, carbon residue, and sulfur content of the hydrogenated oil fraction at temperatures not lower than 300°C were analyzed, and the results are shown in Table 4.

[0103] Comparative Examples 5-8

[0104] Vacuum residue (see Table 3) was selected as feedstock, and a fixed-bed process was used to evaluate the activity of the catalysts obtained in Comparative Examples 1-4. A hydrotreating protectant (FZC-100B) and a hydrodemetallization catalyst (FZC-204A) were loaded before the above catalysts. The loading volume ratio of the protectant, hydrodemetallization catalyst, and the catalysts obtained in the comparative examples was 1:2:4. The operating conditions were: reaction temperature 390℃, reaction pressure 20.0 MPa, hydrogen-to-oil volume ratio 1500:1, and liquid hourly space velocity (LISH) 0.15 h⁻¹. -1 After 1000 hours of reaction evaluation, the nitrogen content, carbon residue, and sulfur content of the hydrogenated oil fraction at temperatures not lower than 300°C were analyzed, and the results are shown in Table 4.

[0105] Table 4. Properties of the fixed-bed hydrogenation product oils obtained in each example.

[0106] 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] As can be seen from the evaluation results in Table 4, the catalyst of the present invention has good hydrodenitrification, hydrodecarbonization and desulfurization activities when used in the hydrotreating process of residual oil.

Claims

1. A residue oil hydrodenitrification catalyst, comprising a support, a hydrotreating active metal component, and an additive, wherein the hydrotreating active metal component comprises tungsten sulfide, molybdenum sulfide, and nickel sulfide; the additive is gallium; the catalyst is characterized by TEM-EDS, and the W to Mo atomic ratio at the active phase center is 2-60 times that at the active phase edge; in the catalyst, tungsten sulfide is mainly distributed at the active phase center, and molybdenum sulfide is mainly distributed at the active phase edge, wherein... The active phase center is located at a distance of more than 3.0 nm from the edge endpoint of the active phase, while the active phase edge refers to a distance of 0-2 nm from the edge endpoint of the active phase. The active phase in the catalyst is a coated active phase with a WS2 crystal structure as the core support, MoS2 as the outer layer, and low-coordination elements nickel and gallium modified on the surface.

2. The catalyst according to claim 1, characterized in that, Characterized by TEM-EDS, the ratio of W to Mo atoms at the active phase center is 5-40 times that at the active phase edge.

3. The catalyst according to claim 1, characterized in that, The carrier is selected from at least one of alumina, silicon oxide, amorphous silicon-aluminum, titanium-aluminum composite oxide, and titanium-silicon composite oxide.

4. The catalyst according to claim 3, characterized in that, The carrier is aluminum oxide.

5. The catalyst according to claim 3, characterized in that, The carrier also contains conventional additives, which are selected from one or more of phosphorus and boron. The mass content of the conventional additives in the carrier, calculated by element, is less than 15%.

6. The catalyst according to claim 1 or 3, characterized in that, The carrier has the following properties: specific surface area of ​​160-380 m² 2 / g, pore volume 0.6-1.2 m 3 / g.

7. The catalyst according to claim 6, characterized in that, The carrier has the following properties: specific surface area of ​​200-320 m². 2 / g, pore volume 0.7-1.1 m 3 / g.

8. The catalyst according to claim 1 or 3, characterized in that, Based on the quality of the catalyst, the mass content of the support is 55%-85%.

9. The catalyst according to claim 8, characterized in that, Based on the quality of the catalyst, the mass content of the support is 60%-80%.

10. The catalyst according to claim 1, characterized in that, Based on catalyst mass, the tungsten content is 5%-15% by mass, the molybdenum content is 3%-15% by mass, the nickel content is 1%-5% by mass, and the gallium content is 0.3%-3.0% by mass.

11. The catalyst according to claim 10, characterized in that, Based on catalyst mass, the tungsten content is 6%-12% by mass, the molybdenum content is 4%-12% by mass, the nickel content is 2%-4% by mass, and the gallium content is 0.5%-2.5% by mass.

12. A method for preparing the catalyst according to any one of claims 1-11, comprising: (1) Impregnate the support with a tungsten-containing impregnation solution, dry and calcine to obtain a catalyst intermediate containing tungsten oxide; (2) Sulfide the catalyst intermediate from step (1) to obtain sulfidated catalyst intermediate I; (3) The sulfidated catalyst intermediate I obtained in step (2) is mixed with an organic solution containing sulfur and organic molybdenum and reacted in the presence of hydrogen to obtain the sulfidated catalyst intermediate II. (4) The sulfide catalyst intermediate II obtained in step (3) is mixed with an organic solution containing sulfur, organonitrile and organogallium, and reacted in the presence of hydrogen to obtain the catalyst.

13. The preparation method according to claim 12, 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%.

14. The preparation method according to claim 13, characterized in that, In step (1), based on the mass of the catalyst intermediate, the mass content of tungsten, calculated as an element, is 7%-15%.

15. The preparation method according to claim 12, characterized in that, In step (3), the organic solution containing sulfur and organic molybdenum includes organic molybdenum, a sulfiding agent, and an organic solvent.

16. The preparation method according to claim 15, characterized in that, The organic molybdenum is one or more of dialkyl dithiophosphate molybdenum, dialkyl dithiocarbamate molybdenum, dithiocarbamate molybdenum, naphthenic acid molybdenum, alkyl salicylate molybdenum, and carbonyl molybdenum, wherein the alkyl carbon number is 3-20; and / or, the vulcanizing 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 jet fuel, and industrial white oil.

17. The preparation method according to claim 16, characterized in that, The alkyl group has 4-15 carbon atoms.

18. The preparation method according to claim 16, characterized in that, In the organic solution containing sulfur and organic molybdenum, the mass content of organic molybdenum is 0.1%-10.0%; and / or, the mass content of the vulcanizing agent is 0.5%-5.0%.

19. The preparation method according to claim 18, characterized in that, In the organic solution containing sulfur and organic molybdenum, the mass content of organic molybdenum is 0.5%-8.0%; and / or, the mass content of the vulcanizing agent is 1.0%-3.0%.

20. The preparation method according to claim 12, characterized in that, In step (3), the mass ratio of the sulfidated catalyst intermediate I obtained in step (2) to the organic solution containing sulfur and organic molybdenum is 1:3-1:

30.

21. The preparation method according to claim 20, characterized in that, In step (3), the mass ratio of the sulfidated catalyst intermediate I obtained in step (2) to the organic solution containing sulfur and organic molybdenum is 1:5-1:

20.

22. The preparation method according to claim 12, 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, the temperature at 200-320℃, and the reaction time is 1.0-6.0 hours; in the second stage, the pressure is controlled at 0.5-10.0 MPa, the temperature at 260-380℃, and the reaction time is 2.0-8.0 hours.

23. The preparation method according to claim 22, characterized in that, In step (3), the reaction process is divided into two stages: in the first stage, the pressure is controlled at 1.0-6.0 MPa, the temperature is controlled at 220-280℃, and the reaction time is controlled at 2.0-4.0 hours; in the second stage, the pressure is controlled at 1.0-6.0 MPa, the temperature is controlled at 280-360℃, and the reaction time is controlled at 3.0-6.0 hours.

24. The preparation method according to claim 12, characterized in that, In step (4), the organic solution containing sulfur, organonickel and organogallium includes a sulfiding agent, organonickel, organogallium and an organic solvent.

25. The preparation method according to claim 24, characterized in that, The organonickel is one or more of nickel benzoate, nickel acetylacetonate, nickel salicylate, alkylphenyl salicylate, nickel citrate, nickel carbonyl, and nickel stearate, wherein the alkyl group has 3-20 carbon atoms; and / or, the organogallium is one or more of trimethylaminogallium, trimethylgallium, maltol gallium, isopropoxide gallium, triisopropylgallium, triethylgallium, ethoxygallium, and gallium acetylacetonate; and / or, the sulfiding agent is one or more of dimethyl disulfide, carbon disulfide, diallyl trisulfide, and diallyl disulfide.

26. The preparation method according to claim 25, characterized in that, The alkyl group has 4-15 carbon atoms.

27. The preparation method according to claim 24, characterized in that, In the organic solution containing sulfur, organonitrile and organogallium, the organonitrile has a mass content of 0.1%-4.0%; and / or, the organogallium has a mass content of 0.05%-2.0%; and / or, the sulfiding agent has a mass content of 0.5%-5.0%.

28. The preparation method according to claim 27, characterized in that, In the organic solution containing sulfur, organocniole and organogallium, the organocniole content is 0.2%-3.0% by mass; and / or, the organogallium content is 0.1%-1.0% by mass; and / or, the sulfiding agent content is 1.0%-3.0% by mass.

29. The preparation method according to claim 12, characterized in that, In step (4), the mass ratio of the organic solution containing sulfur, organonitrile and organogallium to the sulfide catalyst intermediate II obtained in step (3) is 30:1-3:

1.

30. The preparation method according to claim 12, characterized in that, In step (4), the mass ratio of the organic solution containing sulfur, organonitrile and organogallium to the sulfide catalyst intermediate II obtained in step (3) is 20:1-5:

1.

31. The preparation method according to claim 12, characterized in that, In step (4), the reaction process is divided into two stages: in the first stage, the pressure is controlled at 0.5-10.0 MPa, the temperature at 200-320℃, and the reaction time is 1.0-6.0 hours; in the second stage, the pressure is controlled at 0.5-10.0 MPa, the temperature at 260-380℃, and the reaction time is 2.0-8.0 hours.

32. The preparation method according to claim 31, characterized in that, In step (4), the reaction process is divided into two stages: in the first stage, the pressure is controlled at 1.0-6.0 MPa, the temperature is controlled at 220-280℃, and the reaction time is controlled at 2.0-4.0 hours; in the second stage, the pressure is controlled at 1.0-6.0 MPa, the temperature is controlled at 280-360℃, and the reaction time is controlled at 3.0-6.0 hours.

33. The use of the catalyst according to any one of claims 1-11 in the hydrotreating of residual oil.