A hydrodesulfurization catalyst and its preparation method

Abstract

This invention provides a hydrodesulfurization catalyst and its preparation method. The hydrodesulfurization catalyst of this invention comprises a support and an active component, preferably including an auxiliary agent. The support comprises a silicon-modified nickel-aluminum alloy, the active component is an organomolybdenum, preferably alkyl dithiophosphate molybdenum and / or alkyl dithiocarbamate molybdenum, and the auxiliary agent is an organozinc, preferably alkyl dithiophosphate zinc and / or alkyl dithiocarbamate zinc. This hydrodesulfurization catalyst exhibits strong hydrodesulfurization capability for inferior feedstocks with high aromatic hydrocarbon and high residual carbon content.

Description

Technical Field

[0001] This invention relates to a hydrogenation catalyst, specifically to a hydrodesulfurization catalyst and its preparation method. Background Technology

[0002] Traditional alumina-nickel-molybdenum hydrogenation catalysts have a limited nickel content for hydrogenation, which limits their hydrogenation activity when processing feedstocks with high aromatic content. In addition, traditional hydrogenation catalysts not only require high temperature and high pressure, but are also prone to problems such as coking and carbon deposition.

[0003] CN103285914A discloses a method for preparing a hydrogenation pretreatment catalyst containing a silica-alumina-phosphorus-alumina composite molecular sieve. The method uses a silica-alumina-phosphorus-alumina composite molecular sieve, macroporous alumina, and modified alumina as a support. One or more Group VIB and Group VIII metals are used as active components, and P2O5 is used as a promoter. The catalyst exhibits excellent aromatic ring hydrogenation saturation performance and CN bond cleavage ability during the hydrogenation treatment of inferior wax oil, thereby improving the catalyst's hydrogenation dearomatization and hydrogenation denitrogenation performance. However, the strongly acidic support has a significant negative impact on the long-term stability of the catalyst.

[0004] CN111715232A discloses a supported hydrotreating catalyst and its preparation method. The method involves dissolving a salt of an active metal component in water to obtain an impregnation solution, which is then used to impregnate a support. The resulting mixture is then subjected to pressure treatment at 110-300°C under pressure of 0.2-20 MPa for 1-20 hours. The resulting solid is dried and calcined to obtain the supported hydrotreating catalyst. This catalyst exhibits excellent hydrodesulfurization performance even with extremely low active metal content, and the preparation method is simple and inexpensive. However, this catalyst shows poor activity at higher metal contents, making it unsuitable for deep hydrotreating of oil products.

[0005] CN102302935A discloses a catalyst for the hydrodearomatization of petroleum products and its preparation method. The catalyst is prepared by loading a certain amount of active component Ni or Cu onto an Al2O3-TiO2-ZnO composite oxide support. This catalyst can be used for the hydrodearomatization of solvent oils and gasoline, exhibiting good low-temperature catalytic activity and resistance to sulfur and arsenic poisoning. However, this catalyst contains many small pores, resulting in poor hydrotreating effect on distillate oils with larger molecular weights. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a hydrodesulfurization catalyst and its preparation method. This hydrodesulfurization catalyst exhibits strong hydrodesulfurization capability for inferior feedstocks with high aromatic hydrocarbon and high residual carbon content.

[0007] The first aspect of the present invention provides a hydrodesulfurization catalyst, the hydrodesulfurization catalyst comprising a support and an active component, preferably including an auxiliary agent, the support comprising a silicon-modified nickel-aluminum alloy, the active component being an organomolybdenum, preferably alkyl dithiophosphate molybdenum and / or alkyl dithiocarbamate molybdenum, and the auxiliary agent being an organozinc, preferably alkyl dithiophosphate zinc and / or alkyl dithiocarbamate zinc.

[0008] Further, the alkyl molybdenum dithiophosphate is selected from one or more of diisopropyl molybdenum dithiophosphate, dibutyl molybdenum dithiophosphate oxysulfide, and diisooctyl molybdenum dithiophosphate. The alkyl molybdenum dithiocarbamate is selected from one or more of dibutyl molybdenum dithiocarbamate and diisopropyl molybdenum dithiocarbamate.

[0009] Further, the alkyl dithiophosphate zinc is selected from one or more of dibutyl dithiophosphate zinc, isodecyl dithiophosphate zinc, diisooctyl dithiophosphate zinc, and di(tetradecyl)alkyl dithiophosphate zinc. The alkyl dithiocarbamate zinc is selected from one or more of diethyl dithiocarbamate zinc, ethylphenyl dithiocarbamate zinc, and dibutyl dithiocarbamate zinc.

[0010] Furthermore, in this invention, the range of choices for the nickel-aluminum alloy is quite wide. The nickel-aluminum alloy has its conventional meaning in the art, and its source is not particularly limited; it can be commercially purchased or self-made, and self-making can be carried out using any feasible method.

[0011] Furthermore, in this invention, the range of nickel and aluminum content in the nickel-aluminum alloy is relatively wide. Preferably, based on the total amount of the nickel-aluminum alloy, the aluminum content (based on elemental concentration) is 50 wt% to 95 wt%, and the nickel content (based on elemental concentration) is 5 wt% to 50 wt%. More preferably, based on the total amount of the nickel-aluminum alloy, the aluminum content (based on elemental concentration) is 70 wt% to 90 wt%, and the nickel content (based on elemental concentration) is 10 wt% to 30 wt%. This preferred embodiment not only allows nickel to effectively combine with sulfur-containing organomolybdenum compounds to improve the hydrogenation performance of the catalyst, but also prevents the nickel content in the nickel-aluminum alloy from becoming too high.

[0012] Further, the silicon-modified nickel-aluminum alloy is an organosilicon-modified nickel-aluminum alloy, specifically an alkoxysilane. More preferably, the alkoxysilane is selected from at least one of methyltrimethoxysilane, triethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, butyltriethoxysilane, and octyltriethoxysilane. Preferably, based on the dry weight of the hydrodesulfurization catalyst, the content of organosilicon compounds in the hydrogenation catalyst, calculated as SiO2, is 0.2%–3%, preferably 0.5%–2%. Using this preferred embodiment, the modified nickel-aluminum alloy as the catalytic substrate in the catalyst can provide a large amount of activated hydrogen, providing conditions for hydrogen transfer. Combined with organomolybdenum, especially dialkyldithiophosphate molybdenum and / or alkyldithiocarbamate molybdenum, as active components, the sulfur-containing molybdenum species combine with nickel to form more Ni-Mo-S active sites, providing hydrogenation centers and further improving the utilization rate of molybdenum and the hydrogenation activity of the catalyst.

[0013] Furthermore, based on the dry weight of the hydrogenated sulfur catalyst, the content of Al (calculated as aluminum oxide) is 62%–84%, preferably 68%–80%; the content of Ni (calculated as nickel oxide) is 8%–18%, preferably 9%–15%; the content of molybdenum (calculated as molybdenum trioxide) is 6%–18%, preferably 8%–17%; the content of silicon (calculated as silicon dioxide) is 0.2%–3%, preferably 0.5%–2%; and the content of additives (calculated as metal oxides) is 1.5%–7%, preferably 2%–5.5%.

[0014] Furthermore, in this invention, the dry basis measurement method of the hydrodesulfurization catalyst is as follows: in an air atmosphere, the catalyst is heated from 120°C to 420°C at a rate of 3.0°C per minute, and then calcined for 4.0 hours at 550°C for 2.0 hours at a rate of 3.0°C per minute. The resulting material is analyzed in a dry environment.

[0015] Furthermore, the content of each component in the dry basis can be determined using atomic emission spectrometry (ICP-AES), specifically using an OPTIMA 7000DV atomic emission spectrometer manufactured by PE Corporation. In a typical solution preparation process, 0.1 g of sample is dissolved in a mixed solution with a volume ratio of 3HCl:1HNO3:0.5HF. The mixed solution is then diluted with deionized water to a certain volume, ensuring that the content of the analyte element in the solution is between 1 and 10 ppm, thereby increasing the accuracy of the measurement data.

[0016] Furthermore, the analysis of organometallic compounds in the catalyst can be performed using XPS. The XPS testing conditions include: light source: Mg Kα, energy step: 0.05 eV, scan range: 200-250 eV (molybdenum), 280-300 eV (carbon). When analyzing the valence state of molybdenum, molybdenum species with a 3d5 / 2 orbital binding energy of 227-228 eV are considered to have a valence of 0; those with a valence between 228-229 eV are considered to have a valence of +2; those with a valence between 229-231 eV are considered to have a valence of +4; and those with a valence greater than 231 eV are considered to have a valence of +5 or +6.

[0017] Among them, the 3d5 / 2 orbital of the organometallic molybdenum is between 227 and 229 eV, belonging to molybdenum species with valences between 0 and +2. Other organometallic compounds, such as Ga, were tested using methods similar to those for molybdenum. Analysis revealed that the valence states of these metal additives belonged to organic species with valences between 0 and +1, proving the existence of sulfur-containing organomolybdenum compounds.

[0018] Furthermore, in the catalyst provided by this invention, when using an organometallic zinc compound, since the organometallic zinc compound and the sulfur-containing organomolybdenum compound have similar physicochemical properties, their distribution patterns on the surface of the nickel-aluminum alloy support are similar, and their distribution positions are close, the phase separation of zinc and molybdenum is avoided, making the hydrogenation effect, especially the hydrogenation desulfurization effect, more obvious.

[0019] Furthermore, the present invention allows for a wide range of pore volume selection for the hydrodesulfurization catalyst; preferably, the pore volume of the hydrodenitrogenation catalyst is 0.1–1 cm³. 3 / g, preferably 0.15~0.6cm 3 / g.

[0020] Furthermore, according to a preferred embodiment of the present invention, the average pore size of the hydrodesulfurization catalyst is 4-15 nm, preferably 6-12 nm.

[0021] Furthermore, according to a preferred embodiment of the present invention, in the hydrodesulfurization catalyst, the pore volume of 0-3 nm pores accounts for 1%-10% of the total pore volume, preferably 2%-5%. Using the catalyst under the preferred embodiment is more conducive to the mass transfer and diffusion of reactant molecules.

[0022] Furthermore, according to some embodiments of the present invention, the pore volume of the catalyst in the 0-3 nm range and the total pore volume are determined by nitrogen isothermal adsorption-desorption method.

[0023] A second aspect of the present invention provides a method for preparing the above-mentioned hydrodesulfurization catalyst, comprising:

[0024] An impregnation solution containing organic molybdenum and optional organic zinc is prepared and then impregnated onto a silicon-modified nickel-aluminum alloy support. After drying, a hydrodesulfurization catalyst is obtained.

[0025] Furthermore, the silicon-modified nickel-aluminum alloy carrier is an organosilicon-modified nickel-aluminum alloy carrier, and the method for modifying the organosilicon-modified nickel-aluminum alloy carrier includes: contacting the nickel-aluminum alloy with an alkoxysilane gas to perform silicon modification. Preferably, the method further includes a vacuum treatment of the nickel-aluminum alloy before the organosilicon modification and a displacement treatment after the silicon modification. This approach is more conducive to the deposition of alkoxysilanes on the pores of the nickel-aluminum alloy carrier.

[0026] Furthermore, a preferred preparation method for the hydrodesulfurization catalyst of the present invention includes:

[0027] (a) Vacuum treatment of the nickel-aluminum alloy carrier;

[0028] (b) Introduce alkoxysilane gas into the carrier treated in step (a) for modification treatment;

[0029] (c) Replace the alkoxysilane gas described in step (b) with nitrogen and / or an inert gas to obtain a modified nickel-aluminum alloy carrier;

[0030] (d) Prepare an impregnation solution containing organic molybdenum and organic zinc, then impregnate it onto the modified nickel-aluminum alloy support obtained in step (c), and dry it to obtain a hydrodesulfurization catalyst.

[0031] Further, in step (a), the pore volume of the nickel-aluminum alloy carrier is 0.4–1.0 cm³. 3 / g, preferably with a pore volume of 0.5–0.9 cm³. 3 / g, with an average pore size of 4-12nm, preferably 6-10nm, wherein the volume ratio of pores smaller than 3.0nm is not higher than 20%, preferably 5-10%.

[0032] Furthermore, the present invention provides a wide range of particle size selection for the nickel-aluminum alloy carrier, which can be adapted to the actual application environment. Preferably, the average particle size of the nickel-aluminum alloy carrier is 1-8 mm, and more preferably 2-5 mm.

[0033] Further, in step (a), the conditions for the vacuuming process are: a vacuum degree of 0.05-1.0 torr, preferably 0.1-0.5 torr, a processing time of 2-10 hours, preferably 4-8 hours, and a temperature of 50-140℃, preferably 60-120℃.

[0034] Further, in step (b), before introducing the alkoxysilane gas, a heating operation is performed according to the boiling point of the alkoxysilane used, so that the alkoxysilane is in a gaseous state. The alkoxysilane gas is preferably one or more of methyltrimethoxysilane, triethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, isobutyltriethoxysilane, and n-octyltriethoxysilane.

[0035] Further, in step (b), at least one of nitrogen and / or an inert gas is introduced as a carrier gas simultaneously with the alkoxysilane gas. The partial pressure of the alkoxysilane gas is 0.02-1.0 MPa, preferably 0.05-0.5 MPa; the modification treatment temperature is 200-450°C, preferably 250-400°C; the treatment time is 1.0-10.0 hours, preferably 2.0-8.0 hours; and the flow rate of the alkoxysilane gas is 1.0-20.0 mL / min·g. -1 Nickel-aluminum alloy carrier, preferably 3.0-15 mL / min·g -1 Nickel-aluminum alloy carrier.

[0036] Furthermore, in this invention, the inert gas is preferably one or a mixture of several of argon and neon.

[0037] Further, in step (c), the conditions for the displacement include: the inert gas introduction rate is 0.5-5 mL / min·g. -1 Nickel-aluminum alloy carrier, preferably 1-4 mL / min·g -1 The nickel-aluminum alloy carrier has a replacement time of 0.5-8.0 hours, preferably 1.0-4.0 hours, and a temperature of 100-400℃, preferably 150-350℃.

[0038] Further, in step (d), the organomolybdenum source and the organozinc source are mixed with a solvent to prepare an impregnation solution. The organomolybdenum source is one or more of alkyl molybdenum dithiophosphate and / or alkyl molybdenum dithiocarbamate. The organozinc source is one or more of alkyl zinc dithiophosphate and / or alkyl molybdenum dithiocarbamate. The solvent is one or a mixture of n-hexane, n-heptane, n-octane, or n-nonane. In the impregnation solution, the concentrations of the organomolybdenum and organozinc sources are each independently 0.1–3 mol / L.

[0039] Furthermore, in step (d), the impregnation can be performed using at least one of the conventional methods in the art, such as equal-volume impregnation or supersaturated impregnation.

[0040] Further, in step (d), the drying is vacuum drying, with a vacuum degree of 0.5-5.0 torr, preferably 1.0-3.0 torr, a drying temperature of 60-150℃, preferably 70-120℃, and a drying time of 2.0-12.0h, preferably 4.0-8.0h.

[0041] Furthermore, the hydrodesulfurization catalyst needs to be activated before use. The activation conditions include: hydrogen pressure of 0.1-1.0 MPa, preferably 0.2-0.8 MPa; activation temperature of 80-250℃, preferably 120-200℃; activation time of 0.5-5.0 h, preferably 1.0-3.0 h; and hydrogen flow rate of 3.0-15.0 mL / h·g. -1 The preferred hydrodesulfurization catalyst is 5.0-10.0 mL / h·g. -1 Hydrodesulfurization catalyst.

[0042] A third aspect of the present invention provides the application of the aforementioned hydrodesulfurization catalyst in the hydrodesulfurization of secondary processed oil.

[0043] The application conditions include: a reaction temperature of 320-420℃, preferably 340-400℃; a hydrogen pressure of 4.0-20.0 MPa, preferably 8.0-18.0 MPa; a hydrogen-to-oil volume ratio of 400:1-1500:1, preferably 600:1-1200:1; and a volume hourly space velocity of 0.2-2.0 h⁻¹. -1 Preferably 0.3-1.2h -1 .

[0044] The properties of the secondary processed oil are as follows: aromatic content of 30wt% to 80wt%, further 50wt% to 70wt%, and sulfur content of 2000 to 15000 μg·g. -1 The nitrogen content is 500–3000 μg·g -1 。

[0045] Compared with the prior art, the present invention has the following advantages:

[0046] 1. The hydrodesulfurization catalyst of this invention uses alkyl molybdenum dithiophosphate (and / or alkyl molybdenum dithiocarbamate) as the molybdenum source. Due to the steric hindrance effect of alkyl substitution on the surface of the nickel-aluminum alloy, the molybdenum sulfide species are highly dispersed. After mild hydrogen treatment, the resulting Ni-Mo-S active phase has more active centers than the molybdenum species obtained from the oxidized state after sulfidation and unsupported MoS2 particles, thus improving the utilization rate of molybdenum and the hydrogenation activity of the catalyst.

[0047] 2. The hydrodesulfurization catalyst of the present invention uses alkyl dithiophosphate zinc and / or alkyl dithiocarbamate zinc as an additive. Since alkyl dithiophosphate zinc and / or alkyl dithiocarbamate zinc have similar physicochemical properties to specific active components, their distribution patterns on the surface of the modified nickel-aluminum alloy carrier are similar and their distribution positions are close, avoiding the phase separation of zinc and molybdenum, thus making the effect of the additive more obvious.

[0048] 3. This invention employs an alkoxysilane-vapor phase deposition method to ensure that alkoxysilane preferentially seals the pores of the catalyst, thereby optimizing the pore structure of the nickel-aluminum alloy catalyst and preventing subsequent deposition of molybdenum metal in the pores. At the same time, the silicon on the surface of the nickel-aluminum alloy can effectively divide the nickel surface, preventing the accumulation of molybdenum species on the nickel surface. Detailed Implementation

[0049] The present invention will be further described below with reference to the embodiments, but the following embodiments do not constitute a limitation of the present invention. Unless otherwise specified, the percentage content of the materials mentioned herein is a mass percentage content.

[0050] The nickel-aluminum alloy particles used in the embodiments and comparative examples of this invention have the following properties: average particle size 4.1 mm, pore volume 0.72 cm³. 3 / g, the average pore size of the carrier is 8.3 nm, the volume of pores smaller than 3 nm is 7.6%, the mass fraction of Al is 83.6%, and the mass fraction of Ni is 16.4%.

[0051] Example 1

[0052] 100.0g of nickel-aluminum alloy particles were placed in a vacuum drying oven, with the vacuum level controlled at 0.2 torr, the temperature at 80℃, and the processing time at 4.0 hours.

[0053] The temperature of the vacuum drying oven was raised to 220℃, and nitrogen and methyltrimethoxysilane gas were introduced into it. The partial pressure of methyltrimethoxysilane gas was 0.1 MPa, the gas flow rate was 400 mL / min, and the gas introduction time was 3.0 hours.

[0054] The temperature of the drying oven was adjusted to 160℃, and the drying oven was purged with nitrogen at a rate of 200 mL / min for 1 hour. The resulting modified nickel-aluminum alloy carrier was denoted as L-1.

[0055] Prepare impregnation solution Q-1 by taking 20.0g of molybdenum diisopropyl dithiophosphate, 6.0g of zinc dibutyl dithiophosphate, and 70.0g of n-heptane.

[0056] L-1 was impregnated with Q-1, and then vacuum dried at 70°C with a vacuum degree of 1.0 torr for 4.0 hours. The resulting catalyst is designated Cat-1.

[0057] Example 2

[0058] 100.0g of nickel-aluminum alloy particles were placed in a vacuum drying oven, with the vacuum level controlled at 0.4 torr, the temperature at 100℃, and the processing time at 5.0 hours.

[0059] The temperature of the vacuum drying oven was raised to 240℃, and nitrogen and triethoxysilane were introduced into it. The partial pressure of the triethoxysilane was 0.1 MPa, the gas flow rate was 450 mL / min, and the gas introduction time was 4.0 hours.

[0060] The temperature of the drying oven was adjusted to 170℃, and the drying oven was purged with nitrogen at a rate of 200 mL / min for 1.5 hours. The resulting modified nickel-aluminum alloy carrier was denoted as L-2.

[0061] Prepare impregnation solution Q-2 by taking 25.0g of dibutyl dithiophosphate molybdenum sulfide, 8.0g of diisooctyl dithiophosphate zinc, and 70.0g of n-octane.

[0062] L-2 was impregnated with Q-2, and then vacuum dried at 90°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst is designated Cat-2.

[0063] Example 3

[0064] 100.0g of nickel-aluminum alloy particles were placed in a vacuum drying oven, with the vacuum level controlled at 0.5 torr, the temperature at 120℃, and the processing time at 5.0 hours.

[0065] The temperature of the vacuum drying oven was raised to 270℃, and nitrogen and isobutyltriethoxysilane were introduced into it. The partial pressure of isobutyltriethoxysilane was 0.1 MPa, the gas flow rate was 500 mL / min, and the gas introduction time was 5.0 hours.

[0066] The temperature of the drying oven was adjusted to 200℃, and the drying oven was purged with nitrogen at a rate of 200 mL / min for 2.0 hours. The resulting modified nickel-aluminum alloy carrier was designated L-3.

[0067] Prepare impregnation solution Q-3 by taking 20.0g of molybdenum diisopropyl dithiocarbamate, 4.0g of zinc diethyl dithiocarbamate, and 70.0g of n-nonane.

[0068] L-3 was impregnated with Q-3, and then vacuum dried at 120°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst is designated Cat-3.

[0069] Example 4

[0070] 100.0g of nickel-aluminum alloy particles were placed in a vacuum drying oven, with the vacuum level controlled at 0.5 torr, the temperature at 120℃, and the processing time at 5.0 hours.

[0071] The temperature of the vacuum drying oven was raised to 380℃, and nitrogen and n-octyltriethoxysilane were introduced into it. The partial pressure of n-octyltriethoxysilane was 0.1 MPa, the gas flow rate was 600 mL / min, and the gas introduction time was 5.0 hours.

[0072] The temperature of the drying oven was adjusted to 200℃, and the drying oven was purged with nitrogen at a rate of 200 mL / min for 2.0 hours. The resulting modified nickel-aluminum alloy carrier was designated L-4.

[0073] Prepare impregnation solution Q-4 by taking 25.0g of molybdenum dibutyldithiocarbamate, 6.0g of zinc dibutyldithiocarbamate, and 70.0g of n-decane.

[0074] L-4 was impregnated with Q-4, and then vacuum dried at 120°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst is designated Cat-4.

[0075] Comparative Example 1

[0076] 100.0g of nickel-aluminum alloy particles were placed in a vacuum drying oven, with the vacuum level controlled at 0.5 torr, the temperature at 120℃, and the processing time at 5.0 hours. The resulting nickel-aluminum alloy carrier is designated as DL-1.

[0077] Prepare impregnation solution DQ-1 by taking 20.0g of molybdenum diisopropyl dithiocarbamate, 4.0g of zinc diethyl dithiocarbamate, and 75.0g of n-octane.

[0078] DL-1 was impregnated with DQ-1, and then vacuum dried at 120°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst was designated DCT-1.

[0079] Comparative Example 2

[0080] The preparation method of the modified nickel-aluminum alloy carrier L-3 is the same as in Example 3.

[0081] Prepare solution DQ-2 by taking 20.0g of molybdenum carbonyl, 7.0g of zinc octanoate, and 70.0g of toluene.

[0082] L-3 was impregnated with DQ-2, and then vacuum dried at 120°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst was in its oxidized state.

[0083] Weigh 20.0g of the above-mentioned oxidized catalyst and place it in a tubular reactor for conventional sulfidation treatment. The treatment conditions are as follows: the sulfidation solution is a cyclohexane solution containing 5.0% dithiodimethyl, the sulfidation solution volume is 40.0g / h, the hydrogen pressure is 4.0MPa, the hydrogen flow rate is 200mL / min, the sulfidation temperature is 340℃, and the sulfidation time is 6.0 hours. The obtained catalyst is designated as DCT-2.

[0084] Comparative Example 3

[0085] The preparation method of the modified nickel-aluminum alloy carrier L-3 is the same as in Example 3.

[0086] Take 12.0g of molybdenum disulfide powder and 2.0g of zinc sulfide powder, dissolve them in a mixed solution of 40.0g of n-octane and 30.0g of DMDS, and prepare an impregnation solution labeled DQ-3.

[0087] L-3 was impregnated with DQ-3, and then vacuum dried at 120°C with the vacuum level controlled at 1.0 torr for 4.0 hours. The resulting catalyst was designated DCT-3.

[0088] Activation of catalyst

[0089] 20.0g of catalysts Cat-1, Cat-2, Cat-3, Cat-4, DCT-1, DCT-2, and DCT-3 were weighed and placed into a tubular reactor. The activation conditions were: temperature 120℃, hydrogen pressure 0.5MPa, hydrogen flow rate 150.0mL / min, and activation time 2.0 hours.

[0090] Examples 5-8

[0091] The effects of the activated catalysts Cat-1, Cat-2, Cat-3, and Cat-4 in each embodiment were evaluated. The properties of the feed oil are shown in Table 2.

[0092] 20.0 g of each activated catalyst was loaded into a fixed-bed reactor for hydrogenation evaluation experiments under the following conditions:

[0093] The reaction temperature was 360℃, the hydrogen pressure was 11.0 MPa, the hydrogen-to-oil ratio was 1000:1, and the volume hourly space velocity (VHSV) was 0.8 h⁻¹. -1 After reacting for 1000 hours, the sample analysis results are shown in Table 3.

[0094] Comparative Examples 4-6

[0095] 20.0g of each of the activated catalysts from Comparative Examples 1-3 were loaded into a fixed-bed reactor for hydrogenation evaluation experiments. The feedstock and reaction conditions were the same as in Example 5.

[0096] Table 1. Catalyst composition and properties

[0097]

[0098]

[0099] Table 2 Properties of Crude Oil

[0100]

[0101] Table 3 Catalyst Evaluation Results

[0102]

[0103]

[0104] The evaluation results show that the hydrodesulfurization catalyst of this invention has good hydrorefining effect and aromatic saturation effect on heavy secondary processed oil products.

Claims

1. A hydrodesulfurization catalyst, characterized in that, The hydrodesulfurization catalyst includes a support, an active component, and an auxiliary agent. The support includes an organosilicon-modified nickel-aluminum alloy. The active component is an organomolybdenum, wherein the organomolybdenum is alkyl dithiophosphate molybdenum and / or alkyl dithiocarbamate molybdenum. The auxiliary agent is an organozinc, wherein the organozinc is alkyl dithiophosphate zinc and / or alkyl dithiocarbamate zinc.

2. The hydrodesulfurization catalyst according to claim 1, characterized in that, The alkyl dithiophosphate molybdenum is selected from one or more of diisopropyl dithiophosphate molybdenum, dibutyl dithiophosphate molybdenum sulfide, and diisooctyl dithiophosphate molybdenum; the alkyl dithiocarbamate molybdenum is selected from one or more of dibutyl dithiocarbamate and diisopropyl dithiocarbamate.

3. The hydrodesulfurization catalyst according to claim 1, characterized in that, The alkyl dithiophosphate zinc is selected from one or more of dibutyl dithiophosphate zinc, isodel dithiophosphate zinc, diisooctyl dithiophosphate zinc, and di(tetria)alkyl dithiophosphate zinc; the alkyl dithiocarbamate zinc is selected from one or more of diethyl dithiocarbamate zinc, ethylphenyl dithiocarbamate zinc, and dibutyl dithiocarbamate zinc.

4. The hydrodesulfurization catalyst according to claim 1, characterized in that, The organosilicon is an alkoxysilane.

5. The hydrodesulfurization catalyst according to claim 4, characterized in that, The alkoxysilane is selected from at least one of methyltrimethoxysilane, triethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, butyltriethoxysilane, and octyltriethoxysilane.

6. The hydrodesulfurization catalyst according to claim 1, characterized in that, Based on the dry total weight of the hydrodesulfurization catalyst, the content of Al (calculated as aluminum oxide) is 62%~84%, the content of Ni (calculated as nickel oxide) is 8%~18%, the content of molybdenum (calculated as molybdenum trioxide) is 6%~18%, the content of silicon (calculated as silicon dioxide) is 0.2%~3%, and the content of additives (calculated as metal oxides) is 1.5%~7%.

7. The hydrodesulfurization catalyst according to claim 6, characterized in that, Based on the dry total weight of the hydrodesulfurization catalyst, the content of Al (calculated as aluminum oxide) is 68%~80%, the content of Ni (calculated as nickel oxide) is 9%~15%, the content of molybdenum (calculated as molybdenum trioxide) is 8%~17%, the content of silicon (calculated as silicon dioxide) is 0.5%~2%, and the content of additives (calculated as metal oxides) is 2%~5.5%.

8. The hydrodesulfurization catalyst according to claim 1, characterized in that, The properties of the hydrodesulfurization catalyst include: a pore volume of 0.1~1 cm³. 3 / g; average pore size is 4~15nm; pore volume of 0~3nm pores accounts for 1%~10% of the total pore volume.

9. The hydrodesulfurization catalyst according to claim 8, characterized in that, The properties of the hydrodesulfurization catalyst include: a pore volume of 0.15~0.6 cm³. 3 / g; average pore size is 6~12nm; pore volume of 0~3nm pores accounts for 2%~5% of the total pore volume.

10. The method for preparing the hydrodesulfurization catalyst according to any one of claims 1-9, characterized in that, include: An impregnation solution containing organic molybdenum and organic zinc was prepared and then impregnated onto an organosilicon-modified nickel-aluminum alloy carrier. After drying, a hydrodesulfurization catalyst was obtained.

11. The method according to claim 10, characterized in that, The method for preparing the organosilicon-modified nickel-aluminum alloy carrier includes: contacting the nickel-aluminum alloy with alkoxysilane gas to perform organosilicon modification.

12. The method according to claim 11, characterized in that, The nickel-aluminum alloy was subjected to vacuum treatment before organosilicon modification and to displacement treatment after organosilicon modification.

13. The method according to claim 10 or 11, characterized in that, The preparation method of the hydrodesulfurization catalyst includes: (a) Vacuum treatment of the nickel-aluminum alloy carrier; (b) Introduce alkoxysilane gas into the carrier treated in step (a) for modification treatment; (c) Replace the alkoxysilane gas described in step (b) with nitrogen and / or an inert gas to obtain a modified nickel-aluminum alloy carrier; (d) Prepare an impregnation solution containing organic molybdenum and organic zinc, then impregnate it onto the modified nickel-aluminum alloy support obtained in step (c), and dry it to obtain a hydrodesulfurization catalyst.

14. The method according to claim 13, characterized in that, In step (a), based on the total amount of the nickel-aluminum alloy, the aluminum content is 50wt% to 95wt% and the nickel content is 5wt% to 50wt%.

15. The method according to claim 14, characterized in that, In step (a), based on the total amount of the nickel-aluminum alloy, the aluminum content is 70wt%~90wt% and the nickel content is 10wt%~30wt%.

16. The method according to claim 13, characterized in that, In step (a), the conditions for vacuuming are: vacuum degree of 0.05-1.0 torr, processing time of 2-10 hours, and temperature of 50-140℃.

17. The method according to claim 16, characterized in that, In step (a), the conditions for vacuuming are: vacuum degree of 0.1-0.5 torr, processing time of 4-8 hours, and temperature of 60-120℃.

18. The method according to claim 13, characterized in that, In step (b), the alkoxysilane gas is selected from one or more of methyltrimethoxysilane, triethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, isobutyltriethoxysilane, and n-octyltriethoxysilane.

19. The method according to claim 13, characterized in that, In step (b), at least one of nitrogen and / or an inert gas is introduced as a carrier gas simultaneously with the alkoxysilane gas; the partial pressure of the alkoxysilane gas is 0.02-1.0 MPa, the modification treatment temperature is 200-450℃, the time is 1.0-10.0 hours, and the flow rate of the alkoxysilane gas is 1.0-20.0 mL / min·g. -1 Nickel-aluminum alloy carrier.

20. The method according to claim 19, characterized in that, The partial pressure of the alkoxysilane gas is 0.05-0.5 MPa, the modification treatment temperature is 250-400℃, the time is 2.0-8.0 hours, and the flow rate of the alkoxysilane gas is 3.0-15 mL / min·g. -1 Nickel-aluminum alloy carrier.

21. The method according to claim 13, characterized in that, In step (c), the conditions for the displacement include: the inert gas introduction rate is 0.5-5 mL / min·g. -1 Nickel-aluminum alloy carrier, replacement time is 0.5-8.0 hours, temperature is 100-400℃.

22. The method according to claim 21, characterized in that, In step (c), the conditions for the displacement include: the inert gas introduction rate is 1-4 mL / min·g. -1 Nickel-aluminum alloy carrier, replacement time is 1.0-4.0 hours, temperature is 150-350℃.

23. The method according to claim 13, characterized in that, In step (d), the organomolybdenum source and the organozinc source are mixed with a solvent to prepare an impregnation solution; the solvent is one or a mixture of several of n-hexane, n-heptane, n-octane or n-nonane; in the impregnation solution, the concentrations of organomolybdenum and organozinc are each independently 0.1~3 mol / L.

24. The method according to claim 13, characterized in that, In step (d), the drying is vacuum drying, with a vacuum degree of 0.5-5.0 torr, a drying temperature of 60-150℃, and a drying time of 2.0-12.0 h.

25. The method according to claim 24, characterized in that, In step (d), the drying is vacuum drying, with a vacuum degree of 1.0-3.0 torr, a drying temperature of 70-120℃, and a drying time of 4.0-8.0 h.

26. The application of the hydrodesulfurization catalyst according to any one of claims 1-9 or the hydrodesulfurization catalyst prepared by any one of claims 10-25 in the hydrodesulfurization of secondary processed oil.

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