A reforming oil hydrogenation de-olefin catalyst, a preparation method and application thereof

Abstract

A reformate hydrodeolefin catalyst comprising a sulfato-containing alumina carrier and an active component comprising Pd 0.22-0.40 mass%, Pt 0.07-0.18 mass%, chlorine 0.4-3.0 mass%, and the sulfato content in the sulfato-containing alumina carrier is 0.3-3.0 mass% based on alumina. The catalyst can effectively remove olefins in reformate with bromine index higher than 4000 mgBr / 100g oil, and no pre-sulfurization is needed before use. The deolefin product with bromine index less than 50 mgBr / 100g oil and aromatic loss less than 0.5 mass% can be obtained.

Description

Technical Field

[0001] This invention relates to a catalyst for selective hydrogenation of hydrocarbon components to remove olefins, its preparation method, and its application. Specifically, it relates to a catalyst for selective hydrogenation of reformed oil to remove olefins, its preparation method, and its application. Background Technology

[0002] Catalytic reforming is one of the cornerstone technologies of modern petroleum refining and petrochemicals. It involves the rearrangement of hydrocarbon molecules in naphtha under specific temperature, pressure, hydrogen-rich conditions, and the presence of a catalyst, transforming it into a reformate rich in aromatics and producing hydrogen as a byproduct. The reformate is not only rich in aromatics but also contains small amounts of olefins. These olefins can polymerize in the extraction solvent, contaminating it, and also affecting the performance of downstream equipment, adsorbents, and catalysts to varying degrees. Furthermore, olefins, especially dienes, are highly reactive and readily form gums and other byproducts, which can contaminate the heat transfer surfaces of operating equipment, thus reducing its efficiency. With the increasing severity of reforming, especially continuous reforming units, the olefin content in reformate is showing a significant upward trend. Therefore, removing olefins from reformate is a pressing industrial challenge.

[0003] Olefins in reformate can be removed using three processes: clay adsorption, molecular sieve catalytic refining, and selective hydrogenation. Clay adsorption and molecular sieve catalytic refining are non-hydrogenation processes, limited to removing olefins from reformate or mixed aromatic hydrocarbons with a bromine index below 1500 mgBr / 100g oil. For removing olefins from reformate with a bromine index above 2000 mgBr / 100g oil, a hydrorefining process is required.

[0004] Selective hydrotreating refers to the selective hydrogenation of reformate and raffinate oils to remove olefins under hydrogen-exposed conditions, achieving deep hydrogenation removal of olefins without saturating aromatics. The catalysts used mainly contain non-precious metals (such as Co-Mo or Ni-Mo) and precious metals (including Pt, Pd, etc.). Conventional sulfide-state non-precious metal Co-Mo or Ni-Mo hydrorefining catalysts are employed at relatively high reaction temperatures (300–350 °C) and relatively low space velocities (2.0–3.0 h⁻¹). -1Operating at these temperatures makes it difficult to achieve deep de-olefinization (bromine index less than 100 mgBr / 100 g oil) and ensure that aromatic hydrocarbon loss during hydrogenation is less than 0.5 wt%. Furthermore, since reformate and reformed hydrogen do not contain sulfur, sulfide-containing non-precious metal Co-Mo or Ni-Mo hydrorefining catalysts are prone to desulfurization and deactivation. Moreover, the sulfur released during the regeneration of Co-Mo or Ni-Mo hydrorefining catalysts severely contaminates the platinum-based catalysts in the reforming reactor. In contrast, catalysts containing precious metals such as Pt and Pd can operate at lower reaction temperatures (100–250 °C) and higher space velocities (5.0–15.0 h⁻¹). -1 Under these conditions, olefins in the reformed oil are deeply removed, the product has a low bromine index, and the loss of aromatics during hydrogenation is minimal.

[0005] CN200710177193.8 discloses a reforming oil hydrogenation catalyst and its preparation method. The catalyst consists of three parts: a main active component, an additive, and a support. The main active component is a dual noble metal component, with Pd as one of the main active components and one of Au, Ag, Pt, Rh, and Ir as the other main active component. The additive is one of Sn, Pb, Sb, and Bi. Inorganic or organic acids are used as competitive adsorbents. By adjusting the pH of the impregnation solution to 4-5, the dual active components are distributed in a shallow, eggshell-shaped layer within the support.

[0006] CN200910056812.7 discloses a catalyst for deolefin removal from reforming oil under hydrothermal conditions, comprising 0.01–6.0 parts of a metal or oxide selected from Pt, Pd, Ru, or Ni; 0.1–5.0 parts of a metal or oxide selected from K, Mg, Ca, or Ba; 0.01–2.0 parts of a metal or oxide selected from lanthanide rare earth elements; and 90–100 parts of a support selected from at least one of SiO2, Al2O3, TiO2, or ZnO. This catalyst can be used in the process of deolefin removal from reforming oil under hydrothermal conditions. It mainly addresses the problems of low catalyst activity, short lifespan, large aromatic hydrocarbon loss, complex preparation process, and large amounts of precious metals in existing technologies. However, this catalyst is only suitable for removing olefins from reforming oil with a bromine index below 1000 mgBr / 100g oil.

[0007] CN201310345192.5 discloses a method for hydrodeolefination of reformed oil. The active component of the catalyst used is at least one of Pt and Pd, with a content of 0.05–0.5 wt%. The promoter is one or both of Sn and Pb, with a content of 0.5–10 wt%, and the remainder is an alumina support. The noble metal is distributed in a thin eggshell pattern on the support, with a shell thickness of 0.05–1 mm. The specific surface area of ​​the catalyst is 50–400 m². 2 / g, pore volume 0.2~1.2cm³ 3 / g, of which pores with a diameter of 5-50nm account for 50-80% of the total pores. The catalyst in this method distributes precious metals in a thin eggshell pattern on the support, with an eggshell thickness of 0.05-1mm, thereby reducing the amount of precious metals used and improving the utilization rate of precious metals. The initial activity of the catalyst is suppressed by adding inorganic metal additives, effectively avoiding the toxicity of organic sulfides to operators and the pollution to the environment. The bromine index of the treated feedstock is less than 10mgBr / 100g oil.

[0008] CN201410254989.9 discloses a selective hydrodeolefinization catalyst for reformed oil, its preparation method, and its application. The catalyst comprises 0.05-0.5 wt% of an active component oxide, 0.5-10 wt% of an auxiliary oxide, and a support. The active component oxide is at least one of the noble metals Pt, Pd, and Ru oxides, and the auxiliary oxide is one or two of the oxides of Na, K, Mg, Ca, Co, Fe, Ni, Mo, and Cu. The support is alumina. The active component of this catalyst exhibits an eggshell-like distribution on the support. The catalyst is passivated with an auxiliary agent, allowing for direct use without organosulfur passivation. The bromine index of the treated feedstock is also below 10 mg Br / 100 g oil. Summary of the Invention

[0009] The purpose of this invention is to provide a catalyst for the selective hydrogenation of reforming oil to remove olefins, its preparation method, and its application. The catalyst is used for the selective hydrogenation of reforming oil to remove olefins, and can effectively remove olefins from the reforming oil. Furthermore, the catalyst does not need to be pre-sulfurized before use.

[0010] The reforming oil hydrodeolefins catalyst provided by this invention comprises a sulfate-containing alumina support and active components in the following amounts calculated based on alumina:

[0011] Pd 0.22–0.40% by mass

[0012] Pt 0.07~0.18% by mass

[0013] Chlorine 0.4–3.0% by mass

[0014] The sulfate content in the sulfate-containing alumina carrier is calculated based on alumina and is 0.3–3.0% by mass.

[0015] This invention uses alumina containing an appropriate amount of sulfate as a support, and then loads an appropriate amount of active components to prepare a catalyst for the hydrodeolefination reaction of reformed oil. It can effectively remove olefins from reformed oil with a bromine index higher than 4000 mgBr / 100g oil, with good selective deolefination effect and low aromatic loss. Detailed Implementation

[0016] This invention uses sulfate-containing alumina as a support. Pd and Pt are introduced into the molded support while maintaining suitable content. After calcination, reduction with hydrogen yields a sulfidated catalyst. This catalyst is used for the selective hydrodeolefins of reformate oils. Pre-sulfurization is not required before use. It effectively removes olefins from reformate oils with high olefin content and a bromine index higher than 4000 mgBr / 100g oil, resulting in a bromine index of less than 50 mgBr / 100g oil and an aromatic loss of less than 0.5% by mass.

[0017] The preferred content of the active component in the catalyst of the present invention is as follows:

[0018] Pd 0.22–0.30% by mass

[0019] Pt 0.07~0.15% by mass

[0020] Chlorine 0.4–2.0% by mass

[0021] The sulfate content in the sulfate-containing alumina carrier is preferably 0.4 to 2.0% by mass, calculated based on alumina. The alumina is preferably γ-alumina.

[0022] The mass ratio of Pd / Pt in the catalyst is preferably 1.5 to 6.0:1, more preferably 2.2 to 3.5:1.

[0023] The Pd and Pt in the catalyst are uniformly dispersed in the support, and the sodium content in the catalyst is not higher than 0.05% by mass, with the sodium content calculated based on alumina.

[0024] The specific surface area of ​​the sulfate-containing alumina carrier is preferably 180–300 m². 2 / g, with a preferred pore volume of 0.50–1.20 mL / g.

[0025] The method for preparing the catalyst of the present invention includes impregnating an alumina support containing sulfate with a solution containing palladium compound, platinum compound and chlorine compound, drying the impregnated solid, activating it in air at 400-650°C, and then reducing it with hydrogen at 350-550°C.

[0026] The sulfate-containing alumina support described above can be prepared in two ways: one is to prepare the sulfate-containing alumina support by molding a sulfate-containing alumina precursor, and the other is to prepare a molded alumina support by using boehmite or high-purity boehmite, and then introduce sulfate into the molded support.

[0027] The sulfate-containing alumina precursor is preferably sulfate-containing boehmite. The boehmite can be prepared using sodium aluminate solution as raw material. The pH of the solution is adjusted to 7.0–7.5 by adding aluminum sulfate, followed by adding sodium carbonate to adjust the pH to 8.0–9.0. The solution is then aged. The resulting solid is washed with water to achieve the desired sulfate content and dried to obtain sulfate-containing boehmite. The preferred aging temperature is 40–95°C.

[0028] For sulfate-containing alumina supports obtained by introducing sulfate ions into a shaped alumina support, the shaped alumina support is prepared using sulfate-free boehmite. The sulfate-free boehmite can be prepared using sodium aluminate solution as raw material, by neutralizing the pH of the slurry to 9-11 by introducing CO2, followed by aging. The resulting solid is then washed with water and dried to obtain the boehmite. The preferred aging temperature is 40-95℃.

[0029] Sulfate-free boehmite can also be prepared as high-purity boehmite by hydrolysis of alkoxyaluminum.

[0030] The method for forming the alumina carrier according to the present invention is as follows: Boehmite or sulfate-containing boehmite is mixed with an extrusion aid and a binder, kneaded until homogeneous, extruded into strips, and then dried and calcined. The extrusion aid is preferably guar gum powder, and the binder can be one or more of nitric acid, acetic acid, and citric acid. The drying temperature is preferably 100–130°C, and the drying time is preferably 6–20 hours; the calcination temperature is preferably 500–700°C, and the calcination time is preferably 2–10 hours.

[0031] In the above molding method, if a sulfate-free boehmite is used to prepare the carrier, the calcined alumina carrier needs to be impregnated with a sulfate-containing compound solution, and then dried and calcined to obtain a sulfate-containing alumina carrier.

[0032] The sulfate ions in the sulfate-containing alumina precursor, or those introduced into the molded carrier, are preferably derived from sulfuric acid, sulfurous acid, sulfates, hydroxylamine sulfate, hydrazine sulfate, pyrosulfuric acid, or ammonium persulfate. The sulfates are preferably aluminum sulfate, ammonium sulfate, or ammonium aluminum sulfate.

[0033] Preferably, the alumina support containing sulfate ions prepared from boehmite or the alumina support prepared from boehmite is treated with steam at 400–700°C for 0.5–120 hours. The steam treatment is preferably carried out in a processor, and the steam introduced into it is preferably saturated or supersaturated steam at 40–150°C. The mass ratio of steam to support used in the steam treatment is 0.2–10, preferably 0.3–5.

[0034] For alumina supports containing sulfate, the supports treated with steam are impregnated with solutions containing palladium, platinum and chlorine compounds, dried and activated, and then reduced with hydrogen.

[0035] For alumina carriers prepared using boehmite, after steam treatment, they need to be impregnated to introduce sulfate ions, then impregnated with solutions containing palladium compounds, platinum compounds, and chlorine compounds, dried, activated, and then reduced with hydrogen.

[0036] In the above method, active components can be introduced into the sulfate-containing alumina support or the aforementioned support after steam treatment using either partial impregnation or co-impregnation methods. Both partial and co-impregnation can be carried out using saturated or supersaturated impregnation methods. During impregnation, the liquid / solid volume ratio of the impregnating solution to the support is 0.4–4.0, preferably 0.8–4.0. A suitable impregnation temperature is 15–40°C, preferably 20–35°C. The prepared impregnating solution should also contain hydrochloric acid to introduce the chlorine component and ensure uniform distribution of the metal component throughout the support. Excess impregnating solution after supersaturated impregnation is removed by filtration or vacuum evaporation of the solvent.

[0037] Preferably, the introduction of active components through impregnation can be carried out using a rotary vacuum evaporator. The specific operation method is as follows: a water-soluble compound containing each active component is prepared as an impregnation solution, which is then used to impregnate an alumina support under conditions of 0.001–0.10 MPa and rotation. The liquid / solid volume ratio of the impregnation solution to the support is 1.1–3.0, and the rotational linear velocity is 0.01–2.0 m / s. After impregnation, drying and calcination activation are performed. The pressure for vacuum rotary impregnation is preferably 0.001–0.08 MPa. Heating and rotation are performed simultaneously during impregnation. The heating temperature, i.e., the impregnation temperature, is preferably 20–90°C, and the rotation speed should not be too fast; the preferred rotational linear velocity is 0.02–0.8 m / s. The impregnation time is preferably 1–8 hours, more preferably 2–4 hours. After vacuum rotary impregnation, the water in the impregnation solution has essentially evaporated, and the catalyst is in a dry state. At this point, the support can be directly removed for drying and activation.

[0038] The present invention prepares an alumina support containing sulfate ions. Sulfate ions can also be introduced into the alumina support by impregnation using the above-mentioned rotary vacuum evaporation method, that is, by impregnation using a rotary vacuum evaporator.

[0039] The palladium-containing compound used to prepare the impregnation solution is preferably palladium chloride, palladium nitrate, palladium acetate, sodium tetrachloropalladium, dichlorotetraamminepalladium, palladium trifluoroacetate, palladium diacetylacetone, or palladium hexafluoroacetylacetone. The platinum-containing compound is preferably chloroplatinic acid, dichlorotetraammineplatinum, ammonium chloroplatinate, platinum trichloride, platinum tetrachloride, dicarbonylplatinum dichloride, dinitrodiaminoplatinum, or sodium tetranitroplatinate. The chlorine-containing compound is preferably hydrochloric acid.

[0040] After the solid impregnated with the active component is dried, it is activated in air. The suitable gas / agent volume ratio for activation is 500–1000:1, and the activation time is preferably 2–8 hours. The activated catalyst needs to be reduced with hydrogen. The suitable reduction temperature is 400–550°C, preferably 430–500°C, the preferred gas / agent volume ratio is 400–1400:1, and the preferred reduction time is 2–6 hours. The catalyst of this invention no longer requires pre-sulfurization before use.

[0041] The present invention provides a method for selective hydrodeolefination of reformate, comprising hydrotreating the reformate at 50–300°C, 0.5–5.0 MPa, and a volume hourly space velocity (VHSV) of 2.0–30.0 h⁻¹. -1 The catalyst is reacted with the hydrodeolefination catalyst described in this invention under hydrogenation conditions with a hydrogen / oil volume ratio of 2 to 500.

[0042] The preferred temperature for the hydrodeolefination reaction of the reformed oil is 100–250°C, the preferred pressure is 1.0–3.0 MPa, and the preferred feed volume hourly space velocity is 4.0–25.0 h⁻¹. -1 The preferred hydrogen / oil volume ratio is 10 to 300.

[0043] The reformed oil is naphtha reformed oil, which can be full-fraction reformed oil, or benzene fraction, BTX (benzene, toluene, xylene) fraction, or reformed residue obtained after aromatic extraction of reformed oil.

[0044] The invention is further illustrated by the following examples, but the invention is not limited thereto.

[0045] Example 1

[0046] Prepare γ-Al2O3 support containing sulfate.

[0047] (1) Preparation of sulfate-containing pseudoboehmite powder

[0048] Take 500 mL of sodium aluminate solution with a concentration of 210 mL / g, add a certain amount of aluminum sulfate solution with a concentration of 55 mL / g, adjust the pH of the slurry to 7.3, heat to 65℃, and react for 60 min with thorough stirring. Add sodium carbonate solution to adjust the pH of the system to 8.4, continue stirring for 60 min, and then heat to 90℃ for aging for 7 h. Wash the filtered cake with 500 mL of deionized water at 90℃ for a total of 10 washes. Dry the filter cake obtained from the last wash at 120℃ for 12 hours to obtain sulfate-containing pseudoboehmite powder.

[0049] (2) Preparation of carrier

[0050] The above-mentioned boehmite powder was mixed evenly in a mass ratio of boehmite powder: guar gum powder: nitric acid: acetic acid: citric acid: water = 50:1:2:3:3:40. The mixture was then extruded into strips, and the wet strips were dried at 120℃ for 12 hours, calcined at 650℃ for 4 hours, and then treated at 650℃ for 4 hours with saturated steam at 100℃ (saturated steam pressure 0.1MPa). The volume ratio of air containing water vapor to carrier was 700 / 1, and the mass ratio of water vapor to carrier was 0.7. This yielded γ-Al2O3 carrier ZT-1 containing sulfate, with a sulfate content of 0.7% by mass and a Na content of 0.01% by mass of dry alumina. The physicochemical properties of the carrier and the sulfate content are shown in Table 1.

[0051] Example 2

[0052] Prepare γ-Al2O3 support containing sulfate.

[0053] Take 500 mL of sodium aluminate solution with a concentration of 210 mL / g, add a certain amount of aluminum sulfate solution with a concentration of 74 mL / g, adjust the pH of the slurry to 7.3, heat to 65℃, and react for 60 min with thorough stirring. Add sodium carbonate solution to adjust the pH of the system to 8.3, continue stirring at high speed for 60 min, and then heat to 90℃ for aging for 2 h. Wash the filtered cake with 500 mL of deionized water at 90℃ for a total of 6 washes. Dry the filter cake obtained from the last wash at 120℃ for 12 hours to obtain sulfate-containing pseudoboehmite powder.

[0054] Take the above-mentioned boehmite powder, extrude it into strips according to the method of step 1(2) in Example, dry and calcine it, and then treat it with water vapor to obtain γ-Al2O3 carrier ZT-2, in which the sulfate content is 1.3% by mass and the Na content is 0.025% by mass of dry alumina. The physicochemical properties of the carrier and the sulfate content are shown in Table 1.

[0055] Example 3

[0056] Prepare γ-Al2O3 support containing sulfate.

[0057] Take 500 mL of sodium aluminate solution with a concentration of 210 mL / g, add a certain amount of aluminum sulfate solution with a concentration of 55 mL / g, adjust the pH of the slurry to 7.2, heat to 65℃, and react for 60 min with thorough stirring. Add sodium carbonate solution to adjust the pH of the system to 8.7, continue stirring for 60 min, and then heat to 90℃ for aging for 72 h. Wash the filtered cake with 500 mL of deionized water at 90℃ for a total of 20 washes. Dry the filter cake obtained from the last wash at 120℃ for 12 hours to obtain sulfate-containing pseudoboehmite powder.

[0058] Take the above-mentioned pseudo-boehmite powder, extrude it into strips according to the method of step 1(2) in Example, dry and calcine it, and then treat it with water vapor to obtain γ-Al2O3 carrier ZT-3, in which the sulfate content is 0.4% by mass and the Na content is 0.008% by mass of dry alumina. The physicochemical properties of the carrier and the sulfate content are shown in Table 1.

[0059] Example 4

[0060] Prepare γ-Al2O3 support containing sulfate.

[0061] (1) Preparation of pseudoboehmite powder

[0062] 1000 mL of a 60 g Al₂O₃ / L sodium aluminate solution was heated to 40 °C. A mixture of CO₂ and air (35% by volume) was introduced while continuously stirring to control the final pH of the slurry to 10.5. The solution was then heated to 90 °C and aged for 60 h. The filter cake was washed with 500 mL of deionized water four times. It was then washed with 500 mL of 0.05% ammonium nitrate solution four times. The filter cake obtained from the final wash was dried at 120 °C for 12 h to obtain boehmite powder.

[0063] (2) Preparation of carrier

[0064] Take the above-mentioned boehmite powder and mix it evenly according to the mass ratio of boehmite powder: guar gum powder: nitric acid: acetic acid: citric acid: water = 50:1:2:3:3:40. Then extrude the mixture into strips, dry the wet strips at 120℃ for 12h, calcine at 650℃ for 4h, and then treat them at 650℃ for 4h by introducing saturated water vapor at 100℃ (saturated steam pressure 0.1MPa). The volume ratio of air containing water vapor to carrier gas / agent is 700 / 1, and the mass ratio of water vapor to carrier is 0.7, thus obtaining γ-Al2O3 carrier.

[0065] (3) Preparation of sulfate-containing carriers

[0066] 100 g of the above-mentioned γ-Al₂O₃ support was used as the impregnation solution in 150 mL of an aqueous solution containing 0.85 g of ammonium sulfate. The γ-Al₂O₃ support was first placed in a rotary vacuum evaporator and vacuumed at 0.02 MPa for 0.5 h. After stopping the vacuum operation, the impregnation solution was introduced, and the support was impregnated at 30 °C for 3 h. Subsequently, the support was impregnated again at 70 °C and 0.02 MPa under rotary conditions, and the water was evaporated to make the solid dry. The solid was dried at 120 °C for 12 h and then calcined in dry air at 500 °C for 2 h to obtain the sulfate-containing γ-Al₂O₃ support ZT-4, in which the sulfate content was 0.7% by mass and the Na content was 0.016% by mass of dry alumina. The physicochemical properties of the support and the sulfate content are shown in Table 1.

[0067] Example 5

[0068] (1) Preparation of carrier

[0069] High-purity boehmite powder synthesized by alkoxyaluminum hydrolysis was mixed evenly with boehmite powder: guar gum powder: nitric acid: acetic acid: citric acid: water in a mass ratio of 50:1:2:3:3:40. The mixture was then extruded into strips, and the wet strips were dried at 120°C for 12 hours and calcined at 650°C for 4 hours to obtain γ-Al2O3 support.

[0070] (2) Preparation of sulfate-containing γ-Al2O3 support.

[0071] Take 100 g of the above γ-Al2O3 support and use 150 mL of an aqueous solution containing 1.56 g of ammonium sulfate as the impregnation solution. Then, following the method in step 4(3), sulfate ions are introduced by rotary vacuum impregnation. After drying and calcination, γ-Al2O3 support ZT-5 containing sulfate ions is obtained, wherein the sulfate content is 1.3% by mass and the Na content is 0.004% by mass of dry alumina. The physicochemical properties of the support and the sulfate content are shown in Table 1.

[0072] Comparative Example 1

[0073] The γ-Al2O3 support prepared in step 4(2) is denoted as DBZT-1, and its physicochemical properties are shown in Table 1.

[0074] Comparative Example 2

[0075] The support was prepared according to the method in Example 4, except that the impregnation solution was prepared using 0.52 g of ammonium sulfide and 150 mL of deionized water. The γ-Al₂O₃ support DBZT-2 was obtained, with an S content of 0.23% by mass of dry-basis alumina. The physicochemical properties of the support are shown in Table 1.

[0076] Comparative Example 3

[0077] The γ-Al2O3 support prepared in step 5(1) is denoted as DBZT-3, and its physicochemical properties are shown in Table 1.

[0078] Comparative Example 4

[0079] The support was prepared according to the method in Example 5, except that the impregnation solution was prepared using 0.52 g of ammonium sulfide and 150 mL of deionized water. The γ-Al₂O₃ support DBZT-4 was obtained, with an S content of 0.23% by mass of dry-basis alumina. The physicochemical properties of the support are shown in Table 1.

[0080] Examples 6-10

[0081] The catalyst of this invention was prepared.

[0082] Take 50 g of alumina support and prepare an impregnation solution with chloroplatinic acid, palladium chloride, and hydrochloric acid, so that the impregnation solution contains 0.10% Pt, 0.25% Pd, and 1.0% Cl (relative to dry alumina mass), with a pH of 5 and a liquid / solid volume ratio of 1.5. Pour the support and impregnation solution into a 500 mL flask and impregnate it for 3 h at 30 °C, 0.08 MPa, and a rotational speed of 0.03 m / s on a rotary vacuum evaporator. Vacuum the solid at 70 °C to allow it to flow and dry. After removal, dry it at 120 °C for 12 h, activate it in dry air at 500 °C and a gas / agent volume ratio of 700 for 4 h, and then reduce it with H2 at 480 °C and a gas / agent volume ratio of 500 for 4 h to obtain the catalyst. The catalyst numbers, supports, and component contents of each example are shown in Table 2.

[0083] Example 11

[0084] The catalyst was prepared according to the method of Example 6, except that the impregnation solution contained 0.07% Pt, 0.28% Pd and 1.0% Cl (relative to dry alumina mass). The component contents of the obtained catalyst Cat-6 are shown in Table 2.

[0085] Example 12

[0086] The catalyst was prepared according to the method of Example 6, except that the impregnation solution contained 0.13% Pt, 0.22% Pd and 1.0% Cl (relative to dry alumina mass). The component contents of the obtained catalyst Cat-7 are shown in Table 2.

[0087] Comparative Example 5

[0088] The catalyst was prepared according to the method of Example 6, except that the support used was DBZT-1. After the catalyst was reduced, 0.12% (relative to the mass of the catalyst) of hydrogen sulfide was added to the catalyst at 425°C in a hydrogen stream to presulfurize the catalyst, and the catalyst was obtained as DBCat-1. The composition content is shown in Table 2, and the sulfur content is 0.10% by mass.

[0089] Comparative Example 6

[0090] The catalyst was prepared according to the method of Example 6, except that the support used was DBZT-2. The component contents of the resulting catalyst, DBCat-2, are shown in Table 2, with a sulfur content of 0.21% by mass.

[0091] Comparative Example 7

[0092] The catalyst was prepared according to the method in Example 6, except that the support used was DBZT-3. After the catalyst was reduced, 0.12% (relative to the mass of the catalyst) of hydrogen sulfide was added to the catalyst at 425°C in a hydrogen stream to pre-sulfurize the catalyst, and the catalyst was obtained as DBCat-3. The component contents are shown in Table 2, and the sulfur content is 0.09% by mass.

[0093] Comparative Example 8

[0094] The catalyst was prepared according to the method of Example 6, except that the support used was DBZT-4. The component contents of the resulting catalyst, DBCat-4, are shown in Table 2, with a sulfur content of 0.22% by mass.

[0095] Comparative Example 9

[0096] The catalyst was prepared according to the method of Example 6, except that the impregnation solution contained 0.05% Pt, 0.1% Pd and 1.0% Cl (relative to dry alumina mass). The component contents of the resulting catalyst DBCat-5 are shown in Table 2.

[0097] Comparative Example 10

[0098] The catalyst was prepared according to the method of Example 6, except that the impregnation solution contained 0.1% Pt, 0.7% Pd and 1.0% Cl (relative to dry alumina mass). The component contents of the resulting catalyst DBCat-6 are shown in Table 2.

[0099] Comparative Example 11

[0100] The catalyst was prepared according to the method of Example 6, except that the impregnation solution contained 0.1% Pt, 0.13% Pd and 1.0% Cl (relative to dry alumina mass). The component contents of the resulting catalyst DBCat-7 are shown in Table 2.

[0101] Example 13

[0102] A 10 mL catalyst was loaded into a high-pressure microreactor evaluation device, using the full-fraction reformed oil shown in Table 3 as feedstock, to evaluate the catalyst's reactivity. The evaluation conditions were: temperature 150℃, pressure 1.70 MPa, and feed mass hourly space velocity (WHSV) 17.5 h⁻¹. -1 The hydrogen / oil volume ratio was 20:1, and the reaction results for each catalyst are shown in Table 4.

[0103] As shown in Table 4, the catalyst of the present invention has a lower product bromine index and lower aromatic hydrocarbon loss compared with the comparative catalyst, indicating that the catalyst of the present invention has high activity and good stability.

[0104] Table 1

[0105]

[0106] Table 2

[0107]

[0108] Table 3

[0109]

[0110] Table 4

[0111]

Claims

1. A catalyst for the hydrodeolefination of reformed oil, comprising a sulfate-containing alumina support and an active component in the following amounts calculated based on alumina: Pd 0.22~0.40% by mass Pt 0.07~0.18% by mass Chlorine 0.4~3.0% by mass The sulfate content in the sulfate-containing alumina support is calculated based on alumina and is 0.3~3.0% by mass, and the Pd / Pt mass ratio in the catalyst is 2.2~6.0:

1.

2. The catalyst according to claim 1, characterized in that... The active component content of the catalyst is as follows: Pd 0.22~0.30% by mass Pt 0.07~0.15% by mass Chlorine 0.4~2.0% by mass The sulfate content in the sulfate-containing alumina carrier is calculated based on alumina and is 0.4~2.0 by mass.

3. The catalyst according to claim 1 or 2, characterized in that... In the catalyst, Pd and Pt are uniformly dispersed in the support, and the sodium content in the catalyst is not higher than 0.05% by mass.

4. The catalyst according to claim 1 or 2, characterized in that... The specific surface area of ​​sulfate-containing alumina supports is 180~300 m². 2 / g, with a pore volume of 0.50~1.20mL / g.

5. A method for preparing the catalyst according to claim 1, comprising impregnating an alumina support containing sulfate with a solution containing a palladium compound, a platinum compound and a chlorine compound, drying the impregnated solid, activating it in air at 400-650°C, and then reducing it with hydrogen at 350-550°C, wherein the mass ratio of Pd / Pt in the solution is 2.2-6.0:

1.

6. The method according to claim 5, characterized in that... The sulfate-containing alumina carrier is prepared by molding a sulfate-containing alumina precursor.

7. The method according to claim 5, characterized in that... The method for preparing the sulfate-containing alumina support involves first preparing a shaped alumina support using boehmite, and then introducing sulfate ions into the shaped support.

8. The method according to claim 5, characterized in that... The method for preparing the sulfate-containing alumina support is to first prepare a shaped alumina support using high-purity boehmite, and then introduce sulfate into the shaped support.

9. The method according to claim 6 or 7, characterized in that... The sulfate-containing alumina carrier or the shaped alumina carrier is treated with steam at 400~700℃ for 0.5~120 hours, and the mass ratio of steam to carrier is 0.2~10.

10. The method according to claim 6, 7 or 8, characterized in that... The sulfate ions in the sulfate-containing alumina precursor or the sulfate ions introduced into the formed alumina carrier are derived from sulfuric acid or sulfates.

11. The method according to claim 10, characterized in that... The sulfate is selected from aluminum sulfate, ammonium sulfate, or aluminum ammonium sulfate.

12. The method according to claim 5, characterized in that... The palladium-containing compound is selected from palladium chloride, palladium nitrate, palladium acetate, sodium tetrachloropalladate, dichlorotetraamminepalladium, palladium trifluoroacetate, palladium diacetylacetonate, or palladium hexafluoroacetylacetonate.

13. The method according to claim 5, characterized in that... The platinum-containing compound is selected from chloroplatinic acid, dichlorotetraammineplatinum, ammonium chloroplatinate, platinum trichloride, platinum tetrachloride, dicarbonylplatinum dichloride, dinitrodiaminoplatinum, or sodium tetranitroplatinate.

14. The method according to claim 5, characterized in that... The chlorine-containing compound is hydrochloric acid.

15. A method for selective hydrodeolefination of reformate, comprising hydrotreating the reformate at 50-300°C, 0.5-5.0 MPa, and a volumetric hourly space velocity (VHSV) of 2.0-30.0 h⁻¹. -1 The catalyst described in claim 1 is reacted with the hydrogenation deolefination catalyst under hydrogenation conditions with a hydrogen / oil volume ratio of 2 to 500.

16. The method according to claim 15, characterized in that... The reformed oil is naphtha reformed oil, or benzene fraction, BTX fraction, or reforming residue obtained after aromatic extraction of reformed oil.

Images