A Mg-modified hydrogenation catalyst and its preparation method

Abstract

This invention discloses a Mg-modified hydrogenation catalyst and its preparation method. The Mg-modified hydrogenation catalyst is a sulfide-state catalyst, comprising a support, active metals Mo and Ni, and Mg. Characterized by TEM-EDS, the Mg content distributed in the Ni-Mo-S active phase region accounts for 65%-90% of the total Mg content. The modified hydrogenation catalyst of this invention can be used to treat low-quality secondary processed heavy oils, exhibiting good processing capacity and stability, especially for feedstocks with high olefin content.

Description

Technical Field

[0001] This invention relates to a method for preparing a hydrogenation catalyst, and more particularly to a Mg-modified hydrogenation catalyst and its preparation method. Background Technology

[0002] Secondary processed heavy oil mainly refers to high-boiling-point components byproducts of certain petroleum fractions after processing (primarily destructive processing), such as cracked tar, thermal cracking residue, lubricating oil refining extract, and catalytic cracking heavy oil. Secondary processed heavy oil contains a large amount of unstable hydrocarbons such as olefins, dienes, and polycyclic aromatic hydrocarbons. These hydrocarbons easily form coke deposits at the acid sites and hydrogenation active sites of the catalyst. To prevent this, it is necessary to reduce the acidity of the support and the relative adsorption capacity of the hydrogenation activity towards hydrocarbons. However, a paradox arises: weakening the acidity of the support weakens the interaction between the support and the metal, leading to the aggregation of active metals during hydrogenation, which is also detrimental to maintaining catalyst activity.

[0003] CN1712134A discloses a method for preparing a hydrogenation catalyst. The catalyst support is composed of amorphous silica-alumina, modified β-zeolite, and alumina, among which the modified β-zeolite possesses high silica content, high crystallinity, small crystallites, a unique pore structure, and acidic properties. This catalyst improves its activity by incorporating a small amount of modified β-zeolite into the amorphous components, while also providing excellent selective ring-opening of cycloalkanes, isomerization of alkanes, moderate hydrocracking of heavy fractions, aromatic saturation, and heteroatom removal performance. However, the introduction of a strongly acidic zeolite as a support in this catalyst can lead to accelerated coking and carbon deposition rates when processing feedstocks with high olefin and diene content, which is detrimental to the long-term operation of the catalyst.

[0004] CN111282560A discloses a coking wax oil hydrogenation catalyst, its preparation method, and its application. The catalyst uses a titanium-aluminum composite oxide as its support, which possesses a high specific surface area and large pore volume, resulting in strong selectivity for hydrodenitrification. However, using a titanium-aluminum composite material with a large specific surface area as the support can lead to increased sensitivity to carbon deposition due to excessively high acid content and overly dispersed metals, resulting in rapid catalyst deactivation.

[0005] CN1896192A discloses a combined process of wax oil hydrotreating and catalytic cracking. This method involves feeding wax oil, catalytic cracking heavy cycle oil, and catalytic cracking diesel oil together into a hydrotreating unit. Hydrotreating occurs in the presence of hydrogen and a hydrotreating catalyst, and the reaction products are separated to obtain gas, hydrotreated naphtha, hydrotreated diesel oil, and hydrotreated tail oil. While this processing method improves the liquid yield of the oil, it consumes a large amount of hydrogen, and the lifespan of the hydrotreating catalyst is significantly shorter than that of conventional fixed-bed hydrotreating catalysts. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a Mg-modified hydrogenation catalyst and its preparation method. The modified hydrogenation catalyst of this invention can be used to treat low-quality secondary processed heavy oils, exhibiting good processing capacity and stability, especially for feedstocks with high olefin content.

[0007] The first aspect of the present invention provides a Mg-modified hydrogenation catalyst, wherein the Mg-modified hydrogenation catalyst is a sulfide-state catalyst, comprising a support, active metals Mo and Ni, and Mg, wherein, characterized by TEM-EDS, the Mg content distributed in the Ni-Mo-S active phase region accounts for 65%-90% of the total Mg content, preferably 70%-88%.

[0008] Furthermore, in the Mg-modified hydrogenation catalyst, the sulfur content at the corner sites of the Ni-Mo-S active phase, characterized by TEM-EDS, is less than 8.0% of the total sulfur content in the Ni-Mo-S active phase, and more specifically, 2.0%-6.0%.

[0009] Furthermore, the Mg-modified hydrogenation catalyst, based on the mass of the Mg-modified hydrogenation catalyst, has a molybdenum content (Mo) of 6.5%-12%, preferably 8.0-10.5%, and a nickel content (Ni) of 1.0%-4.0%, preferably 1.5%-3.5%.

[0010] Furthermore, the Mg-modified hydrogenation catalyst, based on the mass of the Mg-modified hydrogenation catalyst, has a Mg element content of 0.5%-3.0%, preferably 1.0%-2.0%.

[0011] Furthermore, the Mg-modified hydrogenation catalyst, based on the mass of the Mg-modified hydrogenation catalyst, has a sulfur content of 3.0%-8.0%, preferably 4.0-6.0%.

[0012] Furthermore, the Mg-modified hydrogenation catalyst, based on the mass of the Mg-modified hydrogenation catalyst, has a support content of 73%-90%, preferably 73%-85%.

[0013] Further, the carrier is at least one selected from alumina, silicon oxide, and amorphous aluminum silicate. The specific surface area of ​​the carrier is 200-500 m² / g. 2 / g, preferably 250-400m 2 / g, the pore volume of the carrier is 0.4-1.0 cm³. 3 / g, preferably 0.6-0.8cm 3 / g. The carrier may be doped with one or more modifying elements such as phosphorus, silicon, boron, fluorine, and sodium. The modifying element accounts for less than 6.0% of the carrier mass, preferably 0.5%-6.0% of the carrier mass.

[0014] A second aspect of this invention provides a method for preparing a Mg-modified hydrogenation catalyst, the method comprising:

[0015] (1) Sulfide the oxidized hydrogenation catalyst to obtain the sulfide hydrogenation catalyst;

[0016] (2) The sulfurized hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment;

[0017] (3) Pass an organic solution containing Mg into the catalyst treated in step (2) to carry out the reaction and obtain the Mg-modified hydrogenation catalyst.

[0018] Further, in step (1), the oxidized hydrogenation catalyst comprises: a support, active metal components molybdenum and nickel. Based on the mass of the oxidized hydrogenation catalyst, the content of the support is 60%-80%, the content of molybdenum as oxide is 15%-30%, and the content of nickel as oxide is 2%-23%.

[0019] Further, in step (1), the support in the oxidized hydrogenation catalyst is at least one of alumina, silicon oxide, or amorphous silica-alumina. The specific surface area of ​​the support is 200-500 m². 2 / g, preferably 250-400m 2 / g, the pore volume of the carrier is 0.4-1.0 cm³. 3 / g, preferably 0.6-0.8cm 3 / g. The carrier may be doped with one or more modifying elements such as phosphorus, silicon, boron, fluorine, and sodium. The amount of the modifying element added is conventional, preferably 0.5%-6.0% of the carrier mass.

[0020] Furthermore, in step (1), the oxidized hydrogenation catalyst is a catalyst with heavy oil hydrogenation function, which can be prepared by conventional methods in the art or a commercially available catalyst can be purchased.

[0021] Furthermore, in step (1), the sulfidation is full sulfidation, meaning the active metal in the oxidized hydrogenation catalyst reaches a state of complete sulfidation, which can be achieved using a known sulfidation method. For example, the sulfidation conditions are as follows: temperature 240-400℃, preferably 280-380℃; sulfidation time 3-8h; during sulfidation, hydrogen pressure 2.0-12.0MPa, preferably 3.0-10.0MPa; and hydrogen flow rate 2.0-15.0mL·min. -1 ·g-1 Oxidized hydrogenation catalyst, preferably 3.0-10.0 mL·min -1 ·g -1 Oxidized hydrogenation catalyst.

[0022] Further, in step (1), the sulfidation liquid used in the sulfidation treatment comprises a sulfur-containing compound and an organic solvent, wherein the sulfur-containing compound is at least one selected from dimethyl disulfide, carbon disulfide, diethyl sulfide, ethanethiol, n-butanethiol, di-tert-methyl polysulfide, and dimethyl sulfoxide, and the organic solvent is at least one selected from cyclohexane, n-heptane, aviation kerosene, and diesel oil. The mass fraction of the sulfur-containing compound in the sulfidation liquid is 2%-6%, preferably 4%-6%. The flow rate of the sulfidation liquid is 0.5-4.0 mL·h. -1 ·g -1 Oxidized hydrogenation catalyst, preferably 1.0-4.0 mL·h -1 ·g -1 Oxidized hydrogenation catalyst.

[0023] Furthermore, in step (2), the desulfurization treatment is a mild desulfurization treatment, carried out in at least one of the following ways:

[0024] (a) The sulfided hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment using hydrogen gas containing hydrogen sulfide;

[0025] (b) In the presence of hydrogen, the sulfurized hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment with a sulfurized liquid.

[0026] Further, in step (2), the temperature of the desulfurization treatment is 180-370℃, preferably 200-300℃, the treatment time is 4-24 hours, preferably 6-16 hours, and the total pressure is 2.0-18.0MPa, preferably 4.0-15.0MPa.

[0027] Furthermore, the temperature of the desulfurization treatment in step (2) is 50-100°C lower than the temperature of the sulfurization treatment in step (1).

[0028] Further, in method (a), the volume ratio of hydrogen sulfide to hydrogen is 200:1-800:1, preferably 300:1-600:1, and the total gas flow rate is 5-30 mL·min. -1 ·g -1 Oxidized hydrogenation catalyst, preferably 10-20 mL·min -1 ·g -1 Oxidized hydrogenation catalyst.

[0029] Further, in method (b), the sulfiding liquid includes a sulfur-containing compound and an organic solvent, wherein the sulfur-containing compound is at least one selected from dimethyl disulfide, carbon disulfide, diethyl sulfide, ethanethiol, n-butanethiol, di-tert-methyl polysulfide, and dimethyl sulfoxide; and the organic solvent is at least one selected from cyclohexane, n-heptane, aviation kerosene, and diesel oil. The mass fraction of the sulfur-containing compound in the sulfiding liquid is 0.1%-0.6%. During the desulfurization process, the flow rate of the sulfiding liquid is 0.2-2.0 mL·h. -1 ·g -1 Oxidized hydrogenation catalyst, preferably 0.4-1.5 mL·h -1 ·g -1 Oxidized hydrogenation catalyst, hydrogen flow rate 5-30 mL·min -1 ·g -1 Oxidized hydrogenation catalyst, preferably 10-20 mL·min -1 ·g -1 Oxidized hydrogenation catalyst.

[0030] Further, in step (3), the solvent in the organic solution containing Mg is one or more of toluene, cyclohexane, decahydronaphthalene, tetrahydronaphthalene, n-heptane, etc., and the Mg-containing compound is one or more of magnesium stearate, dibutylmagnesium, magnesium pyruvate, L-aspartic acid magnesium, tetraphenylporphyrin magnesium. The Mg-containing organic solution contains 0.2%-2.0% by mass, preferably 0.5%-1.5%.

[0031] Further, in step (3), the reaction temperature is 80-200℃, preferably 100-160℃, the pressure is 0.2-4.0MPa, preferably 0.5-2.0MPa, and the reaction time is 2-12 hours, preferably 4-10 hours. The hydrogen flow rate is 2-20mL·min. -1 ·g -1 Oxidized hydrogenation catalyst, preferably 5-15 mL·min -1 ·g -1 Oxidized hydrogenation catalyst. The flow rate of the organic solution containing Mg is 2-10 mL / h. -1 ·g -1 Oxidized hydrogenation catalyst, preferably 3-8 mL·h -1 ·g -1 Oxidized hydrogenation catalyst.

[0032] A third aspect of the present invention provides the application of the above-mentioned Mg-modified hydrogenation catalyst in the hydrogenation of secondary processing feedstock oil.

[0033] Furthermore, the application is that the Mg-modified hydrogenation catalyst is used to treat secondary processing feedstock oil with an olefin content of not less than 10% by mass. The secondary processing feedstock oil can be at least one of coal-derived synthetic oil, coal tar, fluidized bed residue hydrogenation tail oil, ethylene tar, etc.

[0034] Furthermore, the operating conditions for the application are as follows: a processing temperature of 200-350℃, preferably 250-300℃; a reaction pressure of 4.0-16.0 MPa, preferably 6.0-12.0 MPa; and a liquid hourly space velocity of 0.5-3.0 h⁻¹. -1 Preferably 1.0-2.0h -1 The hydrogen-to-oil volume ratio is 400:1-1600:1, preferably 600:1-1200:1.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] The catalyst of this invention has the advantages of stable hydrogenation activity and low carbon deposition, and is particularly suitable for processing secondary processing feedstocks containing a large amount of olefins and dienes.

[0037] The preparation method of this invention first subjectes the oxidized hydrogenation catalyst to initial sulfidation and specific desulfurization, so that the metal active phase to be modified is in a highly active state with slight desulfurization. The outer layer of the active phase edge is exposed active metal, while effectively preserving the tricoordinated sulfur atoms and stable Ni-Mo-S crystal structure inside the hydrogenation active phase. This allows magnesium to contact the outer metal phase of the active phase more effectively, so that in the obtained modified hydrogenation catalyst, Mg forms a Mg-Ni-Mo-S combined mixed active phase with Ni, Mo and S. At the same time, it weakens the strength of acid centers on the catalyst support surface that are not covered by metal, thereby weakening the strong interaction between the metal and unsaturated hydrocarbons and reducing the acidity of the catalyst. Detailed Implementation

[0038] 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.

[0039] In this invention, the Mg-modified hydrogenation catalyst was characterized by TEM-EDS (transmission electron microscopy-energy dispersive X-ray spectroscopy) using an instrument of model JY / T 011-1996, JEM-1400Flash. The determination process is as follows: the catalyst particles were ground and the sample was prepared by suspension method. 0.1g of the catalyst sample was placed in a 2mL container and ultrasonically dispersed with anhydrous ethanol. The supernatant was collected, and two to three drops were taken with a dropper and dropped onto a 3mm diameter sample mesh. After drying, the sample to be tested was obtained. Then, the sample to be tested was observed and analyzed by TEM, and the Mg content distribution was statistically analyzed by EDS. The ratio of Mg content distributed in the Ni-Mo-S active phase region to the total Mg content (Mg-Ni-Mo-S / Mg) was obtained based on the corresponding peak area of ​​Mg. 总 (This is an example of how the present invention uses the average value obtained by combining 20 TEM images with EDS analysis.)

[0040] In this invention, the sulfur content at the corner sites of the Ni-Mo-S active phase relative to the total sulfur content in the Ni-Mo-S active phase is characterized using the TEM-EDS method. The instrument used is JY / T 011-1996, JEM-1400Flash. The determination process is as follows: The catalyst particles are ground and the sample is prepared using the suspension method. 0.1g of the catalyst sample is placed in a 2mL 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 3mm diameter sample mesh. After drying, the sample to be tested is obtained. Then, the sample to be tested is observed and analyzed using TEM. Any active phase observed under a TEM microscope is selected, and combined with EDS, the sulfur content at the edge of the active phase (which can be considered the corner sites of the active phase) and the sulfur content in the active phase are statistically analyzed. The sulfur content at the corner sites of the Ni-Mo-S active phase relative to the total sulfur content in the Ni-Mo-S active phase is obtained based on the corresponding peak area of ​​sulfur. (Using S...) 边角位 / S 总 (Represented). This invention uses the average value obtained from 20 TEM images combined with EDS analysis.

[0041] The oxidized hydrogenation catalysts used in the following embodiments and comparative examples of this invention were all prepared by the following methods:

[0042] Weigh 1000.0g of alumina dry adhesive powder, add 10.0g of citric acid and 50.0g of guar gum powder, mix well, then add 900.0g of an aqueous solution containing 1.0% acetic acid, knead for 20.0min, and then extrude into strips using a 2.4mm diameter clover-shaped perforated plate. After drying at 120℃ for 6.0h, calcine at 750℃ for 6.0h. The calcined carrier is designated S-0 (analysis showed the specific surface area of ​​the carrier to be 322m²). 2 / g, the pore volume of the carrier is 0.9cm³. 3Weigh 40.0 g of ammonium heptamolybdate tetrahydrate, 25.0 g of nickel nitrate hexahydrate, and 150.0 g of deionized water. Stir thoroughly at 80 °C for 30 min, cool to room temperature, and then dilute to 210.0 mL with deionized water. The resulting solution is denoted as Q-0.

[0043] Take 200g of support S-0, impregnate it with Q-0, air dry it naturally for 24 hours, then dry it at 120℃ for 4 hours, and then calcine it at 420℃ for 4.0 hours. The resulting oxidized hydrogenation catalyst is denoted as CT-0 (by weight of catalyst, the content of support is 84.1%, the content of molybdenum as oxide is 13.2%, and the content of nickel as oxide is 2.7%).

[0044] Example 1

[0045] Take 1000g of cyclohexane and 50.0g of dimethyl disulfide, and the resulting sulfidation solution is denoted as SQ-0.

[0046] Take 1000g of cyclohexane and 2.0g of dimethyl disulfide, and the resulting sulfidation solution is denoted as TQ-1.

[0047] Take 2000g of toluene and 35.0g of tetraphenylporphyrin magnesium, and prepare an organic solution containing magnesium, denoted as MQ-1.

[0048] Take 20.0g of CT-0 and put it into a reaction tube. Use SQ-0 for sulfidation. During the sulfidation process, the hydrogen pressure is 6.0MPa, the hydrogen flow rate is 300.0mL / min, the flow rate of the sulfidation liquid SQ-0 is 40.0mL / h, the sulfidation temperature is 350℃, and the sulfidation time is 6 hours. The sulfidated catalyst is denoted as SCT-0.

[0049] The reaction tube temperature was lowered to 260℃, the hydrogen pressure was adjusted to 5.0 MPa, and the hydrogen flow rate was 200.0 mL / min. TQ-1 was introduced into the reaction tube at a flow rate of 30.0 mL / h, and the treatment time was 9 hours. The obtained catalyst was designated TCT-1.

[0050] The reaction tube temperature was lowered to 110℃, the hydrogen pressure was adjusted to 0.4 MPa, the gas flow rate was 100.0 mL / min, and MQ-1 was introduced into the reaction tube at a flow rate of 80.0 mL / h for 10.0 hours. The resulting catalyst was designated ECT-1.

[0051] Example 2

[0052] The preparation processes of support S-0, solution Q-0, oxidized hydrogenation catalyst CT-0, sulfidation liquid SQ-0, and sulfidation catalyst SCT-0 are the same as in Example 1.

[0053] Take 1000g of cyclohexane and 3.0g of dimethyl disulfide, and the resulting sulfidation solution is denoted as TQ-2.

[0054] Take 1000g of cyclohexane and 2.0g of dimethyl disulfide, and the resulting sulfidation solution is denoted as TQ-2.

[0055] Take 2000g of toluene and 16.0g of L-aspartic acid magnesium, and prepare an organic solution containing magnesium, denoted as MQ-2.

[0056] The reaction tube temperature was lowered to 280℃, the hydrogen pressure was adjusted to 6.0 MPa, and the hydrogen flow rate was 300.0 mL / min. TQ-2 was introduced into the reaction tube at a flow rate of 40.0 mL / h, and the treatment time was 12 hours. The obtained catalyst was designated TCT-2.

[0057] The reaction tube temperature was lowered to 130℃, the pressure adjusted to 0.6 MPa, the gas flow rate was 120.0 mL / min, and MQ-2 was introduced into the reaction tube at a flow rate of 100.0 mL / h for 12.0 hours. The resulting catalyst was designated ECT-2.

[0058] Example 3

[0059] The preparation processes of support S-0, solution Q-0, oxidized hydrogenation catalyst CT-0, sulfidation liquid SQ-0, and sulfidation catalyst SCT-0 are the same as in Example 1.

[0060] Take 1000g of cyclohexane and 4.0g of dimethyl disulfide, and the resulting sulfidation solution is designated as TQ-3.

[0061] Take 2000g of cyclohexane and 7.0g of di-n-butylmagnesium, and prepare an organic solution containing magnesium, denoted as MQ-3.

[0062] The reaction tube temperature was lowered to 300℃, the hydrogen pressure was adjusted to 8.0 MPa, and the hydrogen flow rate was 400.0 mL / min. TQ-3 was introduced into the reaction tube at a flow rate of 40.0 mL / h, and the treatment time was 12 hours. The obtained catalyst was designated TCT-3.

[0063] The reaction tube temperature was lowered to 150℃, the pressure adjusted to 0.8 MPa, the gas flow rate was 140.0 mL / min, and MQ-3 was introduced into the reaction tube at a flow rate of 120.0 mL / h for 14.0 hours. The resulting catalyst was designated ECT-3.

[0064] Example 4

[0065] The preparation process of the sulfidation catalyst SCT-0 is the same as in Example 1.

[0066] The reaction tube temperature was lowered to 280℃, the reaction pressure was adjusted to 6.0 MPa, and a mixture of hydrogen and hydrogen sulfide was introduced into the reaction tube at a volume ratio of 350:1. The total flow rate of the mixed gas was 350 mL / min, and the treatment time was 12 hours. The resulting catalyst was designated TCT-4.

[0067] Take 2000.0g of toluene and 10.0g of magnesium pyruvate to prepare an organic solution containing magnesium, denoted as MQ-4.

[0068] The reaction tube temperature was lowered to 140℃, the pressure adjusted to 0.6 MPa, the gas flow rate was 130.0 mL / min, and MQ-4 was introduced into the reaction tube at a flow rate of 120.0 mL / h for 14.0 hours. The resulting catalyst was designated ECT-4.

[0069] Example 5

[0070] The preparation process of the sulfidation catalyst SCT-0 is the same as in Example 1.

[0071] The reaction tube temperature was lowered to 300℃, the reaction pressure was adjusted to 6.0 MPa, and a mixture of hydrogen and hydrogen sulfide was introduced into the reaction tube at a volume ratio of 550:1. The total flow rate of the mixed gas was 450 mL / min, and the treatment time was 12 hours. The resulting catalyst was designated TCT-5.

[0072] Take 2000.0g of n-octane and 30.0g of magnesium stearate to prepare an organic solution containing magnesium, denoted as MQ-5.

[0073] The reaction tube temperature was lowered to 150℃, the pressure adjusted to 0.6 MPa, the gas flow rate was 130.0 mL / min, and MQ-4 was introduced into the reaction tube at a flow rate of 120.0 mL / h for 14.0 hours. The resulting catalyst was designated ECT-5.

[0074] Comparative Example 1

[0075] 20.0g of CT-0 was loaded into a reaction tube and sulfided using SQ-0. During the sulfidation process, the hydrogen pressure was 6.0MPa, the hydrogen flow rate was 300.0mL / min, the flow rate of the sulfidation liquid SQ-0 was 40.0mL / h, the sulfidation temperature was 350℃, and the sulfidation time was 6.0 hours. The catalyst after sulfidation was designated as DCT-1.

[0076] Comparative Example 2

[0077] The preparation process of catalyst DCT-1 is the same as that of comparative example 1.

[0078] The reaction tube containing DCT-1 was cooled to 260℃, the hydrogen pressure was adjusted to 5.0 MPa, and the hydrogen flow rate was 200.0 mL / min. TQ-1 was then introduced into the reaction tube at a flow rate of 30.0 mL / h for 9 hours. The resulting catalyst was designated DCT-2.

[0079] Comparative Example 3

[0080] The preparation process of the sulfurized hydrogenation catalyst SCT-0 is the same as in Example 1.

[0081] Take 2000g of toluene and 35.0g of tetraphenylporphyrin magnesium, and prepare an organic solution containing magnesium, denoted as DGQ-3.

[0082] The reaction tube containing SCT-0 was cooled to 110℃, the pressure was adjusted to 0.4MPa, and the gas flow rate was 100.0mL / min. DGQ-3 was then introduced into the reaction tube at a flow rate of 80.0mL / h for 10.0 hours. The resulting catalyst was designated DCT-3.

[0083] Comparative Example 4

[0084] The preparation process of catalyst DCT-1 is the same as that of comparative example 1.

[0085] Take 2000g of toluene and 35.0g of tetraphenylporphyrin magnesium, and prepare an organic solution containing magnesium, denoted as DGQ-4.

[0086] The reaction tube containing DCT-1 was cooled to 260°C, the hydrogen pressure was adjusted to 5.0 MPa, the hydrogen flow rate was 200.0 mL / min, and the treatment time was 9 hours. The resulting catalyst was designated DTCT-4.

[0087] The reaction tube temperature was lowered to 110℃, the pressure adjusted to 0.4 MPa, the gas flow rate was 100.0 mL / min, and DGQ-4 was introduced into the reaction tube at a flow rate of 80.0 mL / h for 10.0 hours. The resulting catalyst was designated DCT-4.

[0088] Comparative Example 5

[0089] The preparation process of carrier S-0 is the same as in Example 1.

[0090] Weigh out 40.0g ammonium heptamolybdate tetrahydrate, 25.0g nickel nitrate hexahydrate, 15.0g anhydrous magnesium nitrate, and 150.0g deionized water. Stir thoroughly at 80℃ for 30 minutes, cool to room temperature, and then dilute to 210.0mL with deionized water. The resulting solution is denoted as DQ-5.

[0091] Take 200g of carrier S-0, impregnate it with DQ-5, air dry it naturally for 24 hours, then dry it at 120℃ for 4 hours, and then calcine it at 420℃ for 4.0 hours. The resulting oxidized hydrogenation catalyst is denoted as DCT-0.

[0092] 20.0g of DCT-0 was loaded into a reaction tube and sulfided using SQ-0 (same as in Example 1). During the sulfidation process, the hydrogen pressure was 6.0MPa, the hydrogen flow rate was 300.0mL / min, the flow rate of the sulfidation liquid SQ-0 was 40.0mL / h, the sulfidation temperature was 350℃, and the sulfidation time was 6 hours. The resulting sulfided hydrogenation catalyst was designated as DCT-5.

[0093] Table 1 shows the physicochemical composition of the catalysts obtained in each example.

[0094]

[0095]

[0096] The Mg-modified hydrogenation catalyst was characterized by TEM-EDS to obtain the percentage of Mg content distributed in the Ni-Mo-S active phase region and the percentage of sulfur content at the corner sites of the Ni-Mo-S active phase. See Table 2 for details.

[0097] Table 2

[0098] Catalyst number ECT-1 ECT-2 ECT-3 ECT-4 ECT-5 DCT-1 DCT-2 DCT-3 DCT-4 DCT-5 <![CDATA[Mg-Ni-Mo-S / Mg 总 ,%]]> 79 77 73 79 76 - - 16 48 19 <![CDATA[S 边角位 / S 总 ,%]]> 4.0 4.3 4.5 4.0 3.9 12.6 3.8 11.9 8.6 12.2

[0099] Examples 6-10

[0100] The catalysts obtained in Examples 1-5 were evaluated for activity. The properties of the feedstock oil are shown in Table 3. The hydrogenation of the feedstock was evaluated under the following conditions: reaction temperature 320℃, reaction pressure 8.0 MPa, and liquid hourly space velocity 2.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 800:1, the catalyst was evaluated for 1000 hours, and the evaluation results are shown in Table 4.

[0101] Comparative Examples 6-10

[0102] The catalysts obtained in Comparative Examples 1-5 were evaluated for activity. The properties of the feedstock oil are shown in Table 3. The hydrogenation of the feedstock was evaluated under the following conditions: reaction temperature 320℃, reaction pressure 8.0 MPa, and liquid hourly space velocity 2.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 800:1, the catalyst was evaluated for 1000 hours, and the evaluation results are shown in Table 4.

[0103] Table 3 Properties of Coal-to-Synthetic Oils

[0104]

[0105]

[0106] Table 4 Evaluation Results

[0107]

[0108] As can be seen from the evaluation results in Table 4, the Mg-modified hydrogenation catalyst prepared by the method of the present invention not only has good hydrogenation activity, but also has excellent hydrogenation saturation performance for olefins, and the catalyst has good stability.

Claims

1. A Mg-modified hydrogenation catalyst, characterized in that: The Mg-modified hydrogenation catalyst is a sulfide-state catalyst, comprising a support, active metals Mo and Ni, and Mg. Characterized by TEM-EDS, the Mg content distributed in the Ni-Mo-S active phase region accounts for 65%-90% of the total Mg content. The Mg-modified hydrogenation catalyst is prepared by the following method, including: (1) Sulfide the oxidized hydrogenation catalyst to obtain the sulfide hydrogenation catalyst, wherein the sulfideing is a complete sulfideing; (2) The sulfurized hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment, wherein the desulfurization treatment is a mild desulfurization treatment; (3) Pass an organic solution containing Mg into the catalyst treated in step (2) to carry out the reaction and obtain Mg-modified hydrogenation catalyst.

2. The Mg-modified hydrogenation catalyst according to claim 1, characterized in that: Characterized by TEM-EDS, the Mg content distributed in the Ni-Mo-S active phase region accounts for 70%-88% of the total Mg content.

3. The Mg-modified hydrogenation catalyst according to claim 1, characterized in that: Characterized by TEM-EDS, the sulfur content at the corner sites of the Ni-Mo-S active phase accounts for less than 8.0% of the total sulfur content in the Ni-Mo-S active phase; the sulfur content at the corner sites refers to the sulfur content at the edge endpoint of the active phase, which is less than 1 nm away from the edge endpoint.

4. The Mg-modified hydrogenation catalyst according to claim 3, characterized in that: Characterized by TEM-EDS, the sulfur content at the corner sites of the Ni-Mo-S active phase accounts for 2.0%-6.0% of the total sulfur content in the Ni-Mo-S active phase.

5. The Mg-modified hydrogenation catalyst according to claim 1, characterized in that: Based on the mass of the Mg-modified hydrogenation catalyst, the molybdenum content (Mo) is 6.5%-12.0% and the nickel content (Ni) is 1.0%-4.0%.

6. The Mg-modified hydrogenation catalyst according to claim 5, characterized in that: Based on the mass of the Mg-modified hydrogenation catalyst, the molybdenum content (Mo) is 8.0-10.5% and the nickel content (Ni) is 1.5%-3.5%.

7. The Mg-modified hydrogenation catalyst according to claim 5, characterized in that: Based on the mass of the Mg-modified hydrogenation catalyst, the content of Mg element (calculated as Mg) is 0.5%-3.0%, the content of sulfur element (calculated as S) is 3.0%-8.0%, and the content of support is 73%-90%.

8. The Mg-modified hydrogenation catalyst according to claim 7, characterized in that: Based on the mass of the Mg-modified hydrogenation catalyst, the Mg content (calculated as Mg) is 1.0%-2.0%, the sulfur content (calculated as S) is 4.0%-6.0%, and the support content is 73%-85%.

9. The Mg-modified hydrogenation catalyst according to claim 1, characterized in that: The carrier is at least one of alumina, silicon oxide, and amorphous aluminum silicate; the specific surface area of ​​the carrier is 200-500 m². 2 / g, the pore volume of the carrier is 0.4-1.0 cm³. 3 / g.

10. The Mg-modified hydrogenation catalyst according to claim 9, characterized in that: The specific surface area of ​​the carrier is 250-400 m². 2 / g, the pore volume of the carrier is 0.6-0.8 cm³. 3 / g.

11. A method for preparing the Mg-modified hydrogenation catalyst according to claim 1, comprising: (1) Sulfide the oxidized hydrogenation catalyst to obtain the sulfide hydrogenation catalyst, wherein the sulfideing is a complete sulfideing; (2) The sulfurized hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment, wherein the desulfurization treatment is a mild desulfurization treatment; (3) Pass an organic solution containing Mg into the catalyst treated in step (2) to carry out the reaction and obtain Mg-modified hydrogenation catalyst.

12. The method according to claim 11, characterized in that: In step (1), the oxidized hydrogenation catalyst includes: a support, active metal components molybdenum and nickel; based on the mass of the oxidized hydrogenation catalyst, the content of the support is 60%-80%, the content of molybdenum as oxide is 15%-30%, and the content of nickel as oxide is 2%-23%.

13. The method according to claim 11, characterized in that: In step (1), the sulfidation conditions are as follows: temperature is 240-400℃, sulfidation time is 3-8h, hydrogen pressure is 2.0-12.0MPa, and hydrogen flow rate is 2.0-15.0 mL·min. -1 ·g -1 Oxidized hydrogenation catalyst.

14. The method according to claim 11, characterized in that: In step (2), the desulfurization treatment is carried out in one of the following ways: (a) The sulfided hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment using hydrogen gas containing hydrogen sulfide; (b) In the presence of hydrogen, the sulfurized hydrogenation catalyst obtained in step (1) is subjected to desulfurization treatment with a sulfurized liquid.

15. The method according to claim 14, characterized in that: In step (2), the temperature of the desulfurization treatment is 180-370℃, the treatment time is 4-24 hours, and the total pressure is 2.0-18.0 MPa.

16. The method according to claim 15, characterized in that: In step (2), the temperature of the desulfurization treatment is 200-300℃, the treatment time is 6-16 hours, and the total pressure is 4.0-15.0 MPa.

17. The method according to claim 15, characterized in that: The temperature of the desulfurization treatment in step (2) is 50-100°C lower than the temperature of the sulfurization treatment in step (1).

18. The method according to claim 14, characterized in that: In method (a), the volume ratio of hydrogen sulfide to hydrogen is 200:1-800:1, and the total gas flow rate is 5-30 mL / min. -1 ·g -1 Oxidized hydrogenation catalyst.

19. The method according to claim 18, characterized in that: In method (a), the volume ratio of hydrogen sulfide to hydrogen is 300:1-600:1, and the total gas flow rate is 10-20 mL / min. -1 ·g -1 Oxidized hydrogenation catalyst.

20. The method according to claim 14, characterized in that: In method (b), the sulfiding liquid comprises a sulfur-containing compound and an organic solvent, wherein the sulfur-containing compound is at least one selected from dimethyl disulfide, carbon disulfide, diethyl sulfide, ethanethiol, n-butanethiol, di-tert-nonyl polysulfide, and dimethyl sulfoxide; the organic solvent is at least one selected from cyclohexane, n-heptane, aviation kerosene, and diesel oil; the mass fraction of the sulfur-containing compound in the sulfiding liquid is 0.1%-0.6%; and the flow rate of the sulfiding liquid during desulfurization is 0.2-2.0 mL·h. -1 ·g -1 Oxidized hydrogenation catalyst, hydrogen flow rate 5-30 mL·min -1 ·g -1 Oxidized hydrogenation catalyst.

21. The method according to claim 20, characterized in that: In method (b), during the desulfurization process, the flow rate of the sulfurizing liquid is 0.4-1.5 mL·h. -1 ·g -1 Oxidized hydrogenation catalyst, hydrogen flow rate 10-20 mL·min -1 ·g -1 Oxidized hydrogenation catalyst.

22. The method according to claim 11, characterized in that: In step (3), the organic solution containing Mg is a solvent of one or more of toluene, cyclohexane, decahydronaphthalene, tetrahydronaphthalene, and n-heptane, and the Mg-containing compound is a magnesium stearate, dibutylmagnesium, magnesium pyruvate, magnesium L-aspartate, and magnesium tetraphenylporphyrin; wherein the Mg-containing organic solution contains 0.2%-2.0% by mass of the Mg-containing compound.

23. The method according to claim 22, characterized in that: In step (3), the Mg-containing organic solution contains 0.5%-1.5% Mg compounds by mass.

24. The method according to claim 11, characterized in that: In step (3), the reaction temperature is 80-200℃, the pressure is 0.2-4.0 MPa, and the reaction time is 2-12 hours; the hydrogen flow rate is 2-20 mL·min. -1 ·g -1 Oxidized hydrogenation catalyst; flow rate of organic solution containing Mg: 2-10 mL·h -1 ·g -1 Oxidized hydrogenation catalyst.

25. The method according to claim 24, characterized in that: In step (3), the reaction temperature is 100-160℃, the pressure is 0.5-2.0 MPa, and the reaction time is 4-10 hours; the hydrogen flow rate is 5-15 mL·min. -1 ·g -1 Oxidized hydrogenation catalyst; flow rate of organic solution containing Mg: 3-8 mL·h -1 ·g -1 Oxidized hydrogenation catalyst.

26. The use of a Mg-modified hydrogenation catalyst according to any one of claims 1-10 or a Mg-modified hydrogenation catalyst prepared according to any one of claims 11-25 in the hydrogenation of secondary processing feedstock oil.

Images