Molecular sieve-based support, method for preparing the same, and hydro-upgrading catalyst comprising the same

Abstract

The application discloses a molecular sieve-based carrier and a preparation method thereof, and a hydro-upgrading catalyst containing the molecular sieve-based carrier. The molecular sieve-based carrier comprises 45-90 wt% of a molecular sieve, 0.1-5 wt% of a cobalt-manganese solid solution and the balance of alumina, based on 100% of the weight of the molecular sieve-based carrier. The hydro-upgrading catalyst prepared by using the molecular sieve-based carrier can realize olefin reduction through olefin isomerization / aromatization reaction while efficiently removing sulfur, and can inhibit the occurrence of high-temperature cracking side reactions, thereby improving the yield of gasoline liquid-phase products.

Description

Technical Field

[0001] This invention relates to a support and a hydrotreating catalyst comprising the support, specifically to a molecular sieve-based support and its preparation method, and a hydrotreating catalyst comprising the molecular sieve-based support. Background Technology

[0002] Currently, high-sulfur, high-olefin, and low-octane catalytic gasoline accounts for more than 60% of the gasoline pool in China, while the proportion of low-sulfur, low-olefin, and high-octane alkylate, isomerized, and reformate is relatively low. Therefore, the core of gasoline clean technology focuses on the clean production of catalytic cracking (FCC) gasoline, which simultaneously achieves the triple goals of ultra-deep desulfurization, significant reduction in olefins, and maintenance of octane number.

[0003] In recent years, with increasingly stringent requirements for olefin indicators in petroleum products, the technical contradiction between significantly reducing olefins and maintaining octane number has become increasingly prominent. Precisely because of this, hydrotreating (or hydrodesulfurization-octane number restoration) technology has stood out among numerous technologies for cleaner gasoline production in the FCC, and has even become one of the mainstream technologies, with broad future application prospects. Therefore, developing a hydrotreating catalyst with excellent comprehensive performance is key to the development of this process.

[0004] CN1743425A discloses a catalytic cracking gasoline hydrotreating process, in which full-fraction FCC gasoline (sulfur content 100 mg / kg, olefin content 45 wt%) is passed sequentially through three reactors—feed pretreatment, hydrotreating, and supplementary hydrotreating—without passing through a cut-off tower, achieving a 78% desulfurization rate. The product olefin content is reduced to 35 wt%, RON loss is 1.0 unit, and the product liquid yield is approximately 98.5 wt%. The method provided by this patent is mainly applicable to low-sulfur FCC gasoline feedstocks, and the corresponding catalyst has relatively low hydrodesulfurization activity, making it difficult for the obtained product to meet the production requirements of high-standard clean gasoline.

[0005] CN102167985A discloses a method for upgrading inferior gasoline through hydrodesulfurization, olefin reduction, and octane number restoration. This method employs a two-agent, two-reactor series process. The inferior gasoline does not require pre-fractionation and passes sequentially through a first-stage reactor equipped with a selective hydrodesulfurization catalyst and a second-stage reactor equipped with an octane number restoration catalyst. It can reduce the total sulfur content of catalytic gasoline from 400 mg / kg to less than 30 mg / kg, and the olefin content from 45 vol% to 25 vol%, with a liquid yield greater than 98.5%. The method disclosed in this invention does not pre-treat the catalytic gasoline but directly performs hydrodesulfurization and octane number restoration reactions. The hydrodesulfurization reaction occurs first, resulting in a significant loss of octane number in the product, thus affecting the overall economic viability of the technology.

[0006] CN101885985A discloses a method for producing ultra-low sulfur and high-octane gasoline. This method first introduces inferior full-fraction FCC gasoline into a catalytic distillation reactor, where it contacts a sulfur transfer catalyst, undergoes a sulfide reaction, and is fractionated. The light fraction is then contacted with a hydrocarbon multi-branched isomerization catalyst; the heavy fraction is sequentially contacted with a selective hydrodesulfurization catalyst and a supplementary desulfurization-hydrocarbon isomerization / aromatication catalyst disclosed in patent CN101081370A; finally, the treated light and heavy fractions are blended to obtain ultra-low sulfur and high-octane gasoline. While the method and catalyst disclosed in the aforementioned patent exhibit good desulfurization activity and olefin conversion performance, they employ catalytic distillation technology, which has relatively high requirements for raw materials. If the raw material fluctuates significantly, the product performance becomes unstable, thus limiting the industrialization of this technology.

[0007] The above patents effectively integrate reforming technology into the traditional hydrodesulfurization process, achieving deep desulfurization, significant olefin reduction, and octane number maintenance through a combination of "hydrodesulfurization followed by reforming" or "hydroreform followed by desulfurization." However, despite this, due to the inherent limitations of the catalyst, the performance of the gasoline product after the combined process is still inferior to that of the catalytic feedstock. For example, the hydrodesulfurization activity is relatively low, the octane number loss is still significant despite ensuring olefin reduction, and the yield of gasoline liquid phase products is relatively low.

[0008] CN 1488724A discloses a process and catalyst for producing low-sulfur, low-olefin clean gasoline from FCC gasoline. This process employs a hydrorefining combined aromatization technical route. The accompanying aromatization catalyst includes small-crystal hydrogen-type molecular sieves (HZSM-5, Hβ, HSAPO-11, etc.) of Group IA metals (lithium, sodium, potassium), transition metals (zinc, iron, manganese, nickel, cobalt, molybdenum, tungsten), and lanthanide rare earth metals (lanthanum, cerium). The molecular sieve crystals range from 20 to 800 nm, with the metal oxide content at 1-10 wt% and the molecular sieve content at 50-90 wt%. The catalyst's acidity is adjusted by the combined use of alkali metals and rare earth metals, reducing the amount of strong acid. While the aromatization catalyst provided by this invention effectively solves the problems of reducing olefins and maintaining octane number, it primarily converts olefins into aromatics, which does not meet the current gasoline quality continuous upgrading standards' restrictions on aromatic content. Furthermore, due to the high reaction temperature, the yield of the gasoline liquid phase product is ≤95%.

[0009] CN 1743428A discloses an FCC gasoline hydrotreating catalyst and its preparation method. The key feature of this invention is that the active component of the catalyst comprises oxides from Group VIB or Group VIIIB (molybdenum, tungsten, cobalt, nickel), and is supported on a carrier (Al₂O₃, ZSM-5, β-zeolite, SAPO zeolite, etc.) using Group IIB (zinc, cadmium) or lanthanide metals (lanthanum, cerium) as promoters. The active component content is 5-25%, the promoter content is 1-10%, and the carrier content is 74-94%. This catalyst, by introducing lanthanide elements, ensures a gasoline liquid yield greater than 98.5%; by introducing Group IIB elements, it promotes the isomerization and aromatization functions of the catalyst, reducing the olefin content from 46 vol% to below 35 vol% and the RON loss to less than 1 unit.

[0010] CN101081371A discloses a comprehensively modified HZSM-5 zeolite catalyst. The catalyst is prepared by mixing HZSM-5 with a binder at a weight ratio of 1-4:1, adding guar gum powder (1-3 wt%) and an aqueous solution of HNO3 (2-5% concentration), and then extruding the mixture into strips to obtain a support intermediate. This intermediate is then subjected to hydrothermal modification (400-500℃, space velocity 1-5 h⁻¹). -1 After treatment with steam for 3-6 hours and with organic acids (citric acid, acetic acid, oxalic acid) for 4-8 hours (at 70-90℃), the catalyst support is obtained. The modified support has suitable acidity and pore structure distribution, and exhibits good desulfurization, olefin reduction, and isomerization / aromatization capabilities. When used in FCC gasoline hydrotreating, the olefin content of the product is reduced by 15% v%, and the RON loss is less than 1 unit, but the liquid yield is low, only 98%.

[0011] CN 1183229C discloses a method for effectively reducing octane number and restoring catalyst acidity. This method involves impregnating an active metal nickel oxide onto a zeolite support, followed by modification, to effectively reduce the acid content. The catalyst is characterized by nickel oxide / ZSM-5+β molecular sieve as its main component, with a total acid content of 0.31 mmol / g to 0.65 mmol / g, of which L-acid content is 0.30 mmol / g to 0.60 mmol / g and Brønsted acid content is 0.03 mmol / g to 0.06 mmol / g. The addition of nickel oxide and the reduction in acid content give the catalyst a strong ability to resist carbon deposits. Comparing the catalyst before and after modification, the carbon deposit content decreases by approximately 5 wt% after the reaction. Simultaneously, the liquid yield of gasoline products improves, increasing from over 95% before modification to over 98% after modification, while the octane number loss remains unchanged, essentially remaining below 1 unit.

[0012] In summary, while existing hydroretrograding catalysts exhibit certain hydrodesulfurization and olefin isomerization / aromatic conversion activities, the introduction of molecular sieves into the catalyst, due to the strong acidity and high acid content of these materials, significantly exacerbates the high-temperature cracking activity of the catalyst, thus affecting the liquid-phase yield of gasoline products. Therefore, conducting research on hydroretrograding catalysts, including adjusting the acidity of the support, optimizing the pore structure, and improving the dispersion of active metals on the catalyst surface, is beneficial for improving the overall performance of the catalyst. This is of great significance for effectively overcoming the technical challenges of significantly reducing olefins and maintaining octane number in current gasoline quality upgrades, as well as improving the overall research level of clean catalytic gasoline production technology. Summary of the Invention

[0013] The purpose of this invention is to address the problems existing in the prior art by providing a molecular sieve-based support and its preparation method, as well as a hydrotreating catalyst containing the molecular sieve-based support. This hydrotreating catalyst can efficiently desulfurize while simultaneously reducing olefins through olefin isomerization / aromatization reactions, and inhibiting the occurrence of high-temperature cracking side reactions, thereby improving the yield of gasoline liquid-phase products.

[0014] To achieve the above objectives, the present invention provides a molecular sieve-based support, wherein, based on 100% by weight of the molecular sieve-based support, the molecular sieve-based support comprises 45-90 wt% molecular sieve, 0.1-5 wt% cobalt-manganese solid solution, and the balance alumina.

[0015] Preferably, the molecular sieve-based carrier of the present invention comprises, based on 100% by weight of molecular sieve-based carrier, 55-85 wt% of molecular sieve, 0.3-3 wt% of cobalt-manganese solid solution, and the balance alumina.

[0016] The molecular sieve-based support of the present invention is selected from one or more of ZSM-5, ZSM-22, ZSM-35, SAPO-11, mordenite, Y molecular sieve and beta molecular sieve, with ZSM-5 being preferred.

[0017] The molecular sieve-based support of the present invention, wherein the cobalt-manganese solid solution is (Co x Mn y O4) n Where n is an integer from 1 to 10, 0 < x < 5, 0 < y < 5; preferably, n is an integer from 1 to 5, 0.5 < x < 2, 0.5 < y < 3, and the cobalt-manganese solid solution has crystalline phase characteristics. The crystalline phase characteristics refer to the ability of the cobalt-manganese solid solution to exhibit typical crystalline phase characteristic peaks, including CoMn2O4, Co2MnO4, CoMnO3, and Co2Mn3O8, when subjected to X-ray diffraction testing and compared with an X-ray standard card library.

[0018] The molecular sieve-based support of the present invention preferably contains cubic Co2MnO4 in the cobalt-manganese solid solution. The crystal lattice type of Co2MnO4 belongs to the cubic crystal system and has characteristic diffraction peaks at 2θ = 18.6°, 30.7°, 36.2°, 44.1°, 54.6°, 58.4°, 64.2° and 92.1°.

[0019] In the molecular sieve-based support of the present invention, the content of the cobalt-manganese solid solution should be controlled within the protection range of the present invention. It should not be too low, otherwise it will not achieve the desired effect; nor should it be too high, as it will affect the overall pore distribution of the support and increase the amount of metal used in the hydrogenation catalyst, thereby increasing the production cost of the catalyst, which is not economical and reasonable.

[0020] The molecular sieve-based support of the present invention, wherein the crystal phase composition of the cobalt-manganese solid solution is mainly controlled by the synthesis process, including factors such as composition ratio and high-temperature heat treatment. The cobalt-manganese solid solution can be prepared by: preparing a solution using cobalt nitrate and manganese nitrate as raw materials, adding citric acid and mixing thoroughly. This solution is then placed in a 60°C water bath to slowly evaporate water, gradually forming a sol, which then transforms into a gel. This gel is dried in air at 110°C for 4 hours, and then heat-treated at different temperatures to obtain cobalt-manganese solid solutions of different particle sizes. Alternatively, the cobalt-manganese solid solution can be prepared by: adding citric acid or a mixture of citric acid and acetylacetone as an organic ligand to an aqueous solution of cobalt nitrate and manganese nitrate, adjusting the pH to 0 to 1.5, forming a gel at 50 to 70°C, drying, and calcining to obtain nano-sized cobalt-manganese spinel.

[0021] More preferably, the cobalt-manganese solid solution preparation method recommended by the present invention is as follows: ammonia water is added dropwise to a cobalt-manganese nitric acid mixed solution while stirring, and the pH value of the solution is adjusted to 8-11 to obtain a precipitate; the precipitate is filtered, washed with water, dried at 80-150℃ for 2-10 hours, and calcined at 500-1100℃ for 2-6 hours to obtain the cobalt-manganese solid solution.

[0022] In the preparation of cobalt-manganese solid solution, the molecular sieve-based support of the present invention may be provided in the form of at least one of its nitrates, halides, etc., but the present invention is not specifically limited to this.

[0023] The molecular sieve-based support of the present invention, wherein the alumina is selected from one or more of sodium aluminate, boehmite and alumina sol, preferably boehmite.

[0024] This invention also provides a method for preparing a molecular sieve-based support, specifically comprising the following steps:

[0025] (1) Pretreatment of powder: Cobalt-manganese solid solution with a particle size of less than 10 μm, molecular sieve and alumina powder are mixed, water is added and stirred to prepare slurry, and then the particle size of the slurry is controlled to be below 5 μm by dispersion technology; the slurry is separated into liquid and solid, and the solid is dried to obtain mixed powder containing cobalt-manganese solid solution;

[0026] (2) Carrier molding: The mixed powder obtained in step (1) and the extrusion aid are dry mixed, then kneaded with adhesive and water and extruded into shape.

[0027] (3) Heat treatment of the carrier: The carrier formed by extrusion is dried and calcined to obtain the molecular sieve-based carrier.

[0028] In the preparation method of the molecular sieve-based support of the present invention, in step (3), the drying temperature is not limited to 100-150°C, and the drying time is not limited to 3-8 hours; the calcination temperature is not limited to 500-700°C, and the calcination time is not limited to 3-10 hours.

[0029] The method for preparing the molecular sieve-based support of the present invention includes, but is not limited to, boehmite as the alumina powder.

[0030] The method for preparing the molecular sieve-based carrier of the present invention can be described as follows: the molecular sieve can be added during the mixing process of cobalt-manganese solid solution and alumina powder, and then slurryed; alternatively, the molecular sieve can be added directly as dry powder during the dry mixing process in step (2).

[0031] The method for preparing the molecular sieve-based support of the present invention includes, but is not limited to, ball milling dispersion, ultrasonic dispersion, etc., as long as the effect can meet the particle size requirements of the present invention.

[0032] The method for preparing the molecular sieve-based support of the present invention uses an acid as the solvent, which can be an organic or inorganic acid, preferably at least one selected from oxalic acid, citric acid, nitric acid, and hydrochloric acid. The amount of the solvent used is 1-10% of the mass of the molecular sieve-based support, preferably 1-5%.

[0033] The method for preparing the molecular sieve-based carrier of the present invention may further include adding an extrusion aid during the carrier forming process; the extrusion aid includes, but is not limited to, at least one of guar gum powder, starch, and methylcellulose, preferably guar gum powder, and its amount is 2 to 10% of the mass of the molecular sieve-based carrier, preferably 3 to 7%.

[0034] The present invention also discloses a hydrotreating catalyst, wherein the catalyst comprises a Group VIB metal, a Group VIII metal, and a molecular sieve-based support. Based on 100 parts by weight of the catalyst components, the Group VIB metal is used in an amount of 0.5–10 parts by weight (based on its oxide), the Group VIII metal is used in an amount of 0.1–5 parts by weight (based on its oxide), and the molecular sieve-based support is used in an amount of 85–98 parts by weight. The Group VIII metal includes cobalt, and the mass content of cobalt oxide in the molecular sieve-based support is lower than the mass content of cobalt oxide supported on the catalyst.

[0035] In a further preferred embodiment of the hydrogenation catalyst of the present invention, the amount of the group VIB metal oxide is 1 to 5 parts; the amount of the group VIII metal oxide is 0.2 to 3 parts; and the amount of the molecular sieve-based support is 88 to 95 parts.

[0036] In a further preferred embodiment of the hydrogenation catalyst of the present invention, the group VIB metal is tungsten and / or molybdenum; the group VIII metal includes nickel in addition to cobalt.

[0037] The group VIB and group VIII metals introduced into the hydrogenation catalyst of the present invention during the preparation process can exist in any decomposable form such as oxides, halides or salts.

[0038] The hydrogenation catalyst of the present invention may further be supplemented with alkali metals or alkaline earth metals, wherein the alkali metals or alkaline earth metals are selected from at least one of Li, Na, K, Mg, and Ca, and the alkali metals or alkaline earth metals may be added in the form of oxides, chlorides, or salts.

[0039] The alkali metal or alkaline earth metal added in this invention is based on 100 parts by weight of catalyst components, and the amount of the alkali metal or alkaline earth metal, based on its oxide, is 0.5 to 5 parts.

[0040] The preparation method of the hydrogenation reforming catalyst of the present invention is not particularly limited. The following method can be used: preparing a precursor salt of group VIB metal and group VIII metal into an impregnation solution and supporting it on the surface of a molecular sieve-based support to obtain a catalyst precursor; drying and calcining the catalyst precursor to obtain the hydrogenation reforming catalyst.

[0041] The preparation method of the hydrogenation reforming catalyst of the present invention, wherein the supporting method is, for example, but not limited to, at least one of the following: equal volume impregnation method, spraying method and excess impregnation method; preferably the spraying method, wherein the spraying method includes, but is not limited to: spraying the precursor salt impregnation solution onto the molecular sieve-based support in a rotating drum environment.

[0042] The preparation method of the hydrogenation reforming catalyst of the present invention includes, for example but not limited to, the preparation method of the precursor salt solution of Group VIB and Group VIII metals as follows: First, weigh an appropriate amount of precursor salt of Group VIB and Group VIII metals according to the catalyst formula, and determine the amount of dissolved water of the precursor salt by testing the saturated water absorption rate of the molecular sieve-based support used in the catalyst; then, add the precursor salt to deionized water in sequence, and adjust the pH value by adding concentrated ammonia water, for example, 25% by mass, so that the precursor salt is completely dissolved into a stable mixed solution.

[0043] The preparation method of the hydrogenation reforming catalyst of the present invention includes the following specific drying conditions: drying at 120-150°C for 4-8 hours; and calcination conditions: high-temperature treatment at 550-650°C for 4-8 hours.

[0044] Compared with the prior art, the present invention has at least the following beneficial effects:

[0045] In this invention, some of the active metal cobalt is added to the molecular sieve-based support in the form of a cobalt-manganese solid solution. This not only regulates the dispersion of cobalt grains and avoids the rapid aggregation and growth of cobalt grains during the preparation of hydrogenation catalysts, which would otherwise affect their synergistic effect on the main active component, but also adjusts the total acid content and acid site density of the support.

[0046] The hydrotreating catalyst of this invention exhibits excellent desulfurization capabilities and also demonstrates good olefin conversion ability. The hydrotreating catalyst of this invention undergoes isomerization / aromatization reactions under high temperature and hydrogen-rich conditions, achieving efficient olefin conversion, reducing octane number loss, and resolving the contradiction that the high-temperature over-cracking caused by the isomerization / aromatization reaction during hydrotreating results in low yields of gasoline liquid-phase products. Attached Figure Description

[0047] Figure 1 The image shows the XRD pattern of the molecular sieve-based support sample containing cobalt-manganese solid solution prepared in Example 1. The XRD pattern reveals characteristic peaks for cobalt-manganese solid solution, γ-Al₂O₃, and ZSM-5, indicating that the support sample is a molecular sieve-based support material containing cobalt-manganese solid solution. Detailed Implementation

[0048] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0049] To further illustrate the effects of the method and catalyst used in this invention, examples are given using the hydrotreating catalyst containing cobalt-manganese solid solution prepared in this invention and the corresponding FCC full-fraction gasoline hydrotreating reaction. However, this invention is not limited to the following examples.

[0050] Sources of raw materials used in the preparation of the support and catalyst:

[0051] All raw materials and reagents used in this invention are commercially available products.

[0052] Sources of raw materials used in hydrogenation reforming reactions:

[0053] This invention uses Ningxia Petrochemical FCC full-fraction gasoline as raw material, with a sulfur content of 56.5 mg / kg, an olefin content of 40.71 v%, and a RON content of 91.4%.

[0054] The analytical methods for reactants and products during the hydrogenation reaction are as follows:

[0055] The sulfur content of the oil products described in this invention was analyzed using a TSN-2000 sulfur-nitrogen analyzer. The oil composition was analyzed using an Agilent 7890B gas chromatograph, and data processing was performed using an HW-2000PONA analytical chromatography workstation. The research octane number (RON) of the oil products was tested using an octane rating analyzer.

[0056] The product desulfurization rate, isomer / aromatic conversion rate, research octane number (RON) loss, and liquid yield are calculated using the following formulas:

[0057]

[0058]

[0059] Research Octane Number (RON) Loss = Research Octane Number of Reactants - Research Octane Number of Reactants

[0060]

[0061] Example 1

[0062] Preparation of Co2MnO4: Cobalt nitrate and manganese nitrate are dissolved in deionized water to prepare a cobalt-manganese mixed solution. Ammonia water is added dropwise to the solution while stirring, and the pH of the solution is adjusted to 8.8. This process will produce a precipitate, which is then filtered, washed with water, dried at 110℃ for 6 hours, and calcined at 720℃ for 6 hours to obtain the cobalt-manganese solid solution Co2MnO4.

[0063] Preparation of molecular sieve-based support: Co2MnO4, ZSM-5 / SAPO-11 molecular sieve powder, and pseudoboehmite were added to deionized water and stirred to obtain a homogeneous slurry. The slurry was then dispersed, centrifuged, and dried to obtain Co2MnO4-containing molecular sieve powder. The Co2MnO4-containing molecular sieve powder and methylcellulose were added to a mixer and mixed until homogeneous. Then, an aqueous solution of citric acid was introduced and kneaded to obtain agglomerated material. This material was extruded, dried at 100℃ for 6 hours, and calcined at 600℃ for 6 hours to finally obtain Co2MnO4-containing molecular sieve-based support A-1. The components and contents of molecular sieve-based support A-1 are shown in Table 1.

[0064] Ammonium heptamolybdate and cobalt acetate were dissolved in an ammonia solution to prepare a completely dissolved active component impregnation solution. At room temperature, an equal volume of the active component impregnation solution was impregnated onto a molecular sieve-based support A-1 to obtain a catalyst precursor. The precursor was aged at room temperature for 5 hours, dried at 140℃ for 3 hours, and calcined at 550℃ for 8 hours to obtain the hydrotreating catalyst C-1. The components and their contents in the hydrotreating catalyst C-1 are shown in Table 2.

[0065] Example 2

[0066] Preparation of Co2MnO4 / CoMn2O4: Cobalt acetate and manganese dichloride are dissolved in deionized water to prepare a cobalt-manganese mixed solution. Ammonia water is added dropwise to this solution while stirring, and the pH of the solution is adjusted to 10.7. This process will produce a precipitate, which is then filtered, washed with water, dried at 150℃ for 3.5h, and calcined at 1000℃ for 5h to obtain the cobalt-manganese solid solution Co2MnO4 / CoMn2O4.

[0067] Preparation of molecular sieve-based support: Co2MnO4 / CoMn2O4 and aluminum sol were added to deionized water and stirred to obtain a homogeneous slurry. The slurry was then dispersed, centrifuged, and dried to obtain alumina powder containing Co2MnO4 / CoMn2O4. The alumina powder containing Co2MnO4 / CoMn2O4, SAPO-11 molecular sieve, and methylcellulose were added to a mixer and mixed. After homogeneity, an aqueous solution of nitric acid and acetic acid was introduced and kneaded to obtain agglomerated material. This material was then extruded, dried at 120℃ for 6 hours, and calcined at 520℃ for 3 hours to finally obtain molecular sieve-based support A-2 containing Co2MnO4 / CoMn2O4. The components and contents of molecular sieve-based support A-2 are shown in Table 1.

[0068] Ammonium heptamolybdate, ammonium tungstate, and cobalt nitrate were dissolved in an ammonia solution to prepare a completely dissolved active component impregnation solution. At room temperature, the active component impregnation solution was sprayed onto a molecular sieve-based support A-2 in a rotating drum to obtain a catalyst precursor. After aging at room temperature for 3 hours, it was dried at 120℃ for 6 hours and calcined at 640℃ for 5 hours to obtain the hydrotreating catalyst C-2. The components and contents of the hydrotreating catalyst C-2 are shown in Table 2.

[0069] Example 3

[0070] Preparation of Co2Mn3O8: Cobalt chloride and manganese acetate are dissolved in deionized water to prepare a cobalt-manganese mixed solution. Ammonia water is added dropwise to the solution while stirring, and the pH of the solution is adjusted to 9.4. This process will produce a precipitate, which is then filtered, washed with water, dried at 90℃ for 8.5h, and calcined at 940℃ for 3h to obtain the cobalt-manganese solid solution Co2Mn3O8.

[0071] Preparation of molecular sieve-based support: Co2Mn3O8, ZSM-22 molecular sieve powder, and pseudoboehmite were added to deionized water and stirred to obtain a homogeneous slurry. The slurry was then dispersed, centrifuged, and dried to obtain Co2Mn3O8-containing molecular sieve powder. The Co2Mn3O8-containing molecular sieve powder and guar gum powder were added to a mixer and mixed. After homogeneity, an aqueous solution of nitric acid was introduced and kneaded to obtain agglomerated material. This material was then extruded, dried at 150℃ for 4 hours, and calcined at 510℃ for 8 hours to finally obtain Co2Mn3O8-containing molecular sieve-based support A-3. The components and contents of molecular sieve-based support A-3 are shown in Table 1.

[0072] Ammonium tungstate and cobalt chloride were dissolved in an ammonia solution to prepare a completely dissolved active component impregnation solution. This solution was then applied in excess to a molecular sieve-based support A-3 at room temperature to obtain a catalyst precursor. The precursor was aged at room temperature for 3 hours, dried at 130°C for 7 hours, and calcined at 650°C for 4 hours to obtain the hydrotreating catalyst C-3. The components and their contents in the hydrotreating catalyst C-3 are shown in Table 2.

[0073] Example 4

[0074] Preparation of CoMnO3: Cobalt nitrate and manganese nitrate are dissolved in deionized water to prepare a cobalt-manganese mixed solution. Ammonia water is added dropwise to the solution while stirring, and the pH of the solution is adjusted to 8.3. This process will produce a precipitate, which is then filtered, washed with water, dried at 130℃ for 5 hours, and calcined at 860℃ for 5 hours to obtain cobalt-manganese solid solution CoMnO3.

[0075] Preparation of molecular sieve-based support: CoMnO3, ZSM-5 / SAPO-11 molecular sieve powder, and alumina sol were added to deionized water and stirred to obtain a homogeneous slurry. The slurry was then dispersed, centrifuged, and dried to obtain CoMnO3-containing molecular sieve powder. The CoMnO3-containing molecular sieve powder and methylcellulose were added to a mixer and mixed until homogeneous. An aqueous solution of acetic acid was then introduced and kneaded to form a clump. This clump was extruded, dried at 140℃ for 3 hours, and calcined at 680℃ for 5 hours to finally obtain CoMnO3-containing molecular sieve-based support A-4. The components and contents of molecular sieve-based support A-4 are shown in Table 1.

[0076] Ammonium heptamolybdate, cobalt nitrate, and nickel acetate were dissolved in an ammonia solution to prepare a completely dissolved active component impregnation solution. At room temperature, the active component impregnation solution was sprayed onto a molecular sieve-based support A-4 in a rotating drum to obtain a catalyst precursor. After aging at room temperature for 5 hours, it was dried at 150°C for 2 hours and calcined at 610°C for 6 hours to obtain the hydrotreating catalyst C-4. The components and their contents in the hydrotreating catalyst C-4 are shown in Table 2.

[0077] Example 5

[0078] Preparation of Co2MnO4: Cobalt nitrate and manganese nitrate are dissolved in deionized water to prepare a cobalt-manganese mixed solution. Ammonia water is added dropwise to the solution while stirring, and the pH of the solution is adjusted to 10.1. This process will produce a precipitate, which is then filtered, washed with water, dried at 120℃ for 4 hours, and calcined at 800℃ for 4 hours to obtain the cobalt-manganese solid solution Co2MnO4.

[0079] Preparation of molecular sieve-based support: Co2MnO4, ZSM-5 molecular sieve powder, and pseudoboehmite were added to deionized water and stirred to obtain a homogeneous slurry. The slurry was then dispersed, centrifuged, and dried to obtain Co2MnO4-containing molecular sieve powder. The Co2MnO4-containing molecular sieve powder and guar gum powder were added to a mixer and mixed until homogeneous. Then, an aqueous solution of nitric acid and citric acid was introduced and kneaded to obtain agglomerated material. This material was extruded, dried at 130℃ for 7 hours, and calcined at 560℃ for 4 hours to finally obtain Co2MnO4-containing molecular sieve-based support A-5. The components and contents of molecular sieve-based support A-5 are shown in Table 1.

[0080] Ammonium heptamolybdate, cobalt acetate, and magnesium nitrate were dissolved in an ammonia solution to prepare a completely dissolved active component impregnation solution. At room temperature, the active component impregnation solution was sprayed onto a molecular sieve-based support A-5 in a rotating drum to obtain a catalyst precursor. After aging at room temperature for 5 hours, it was dried at 120°C for 4 hours and calcined at 580°C for 4 hours to obtain the hydrotreating catalyst C-5. The components and contents of the hydrotreating catalyst C-5 are shown in Table 2.

[0081] Comparative Example 1

[0082] The difference from Example 1 is that no cobalt-manganese solid solution Co2MnO4 was added during the preparation of the molecular sieve-based support. Otherwise, the process was the same as in Example 1, resulting in molecular sieve-based support B-1 and hydrogenation-modified catalyst C-D1. The components and contents of molecular sieve-based support B-1 are shown in Table 1, and the components and contents of hydrogenation-modified catalyst C-D1 are shown in Table 2.

[0083] Comparative Example 2

[0084] The difference from Example 1 is that the mass content of CoO in the molecular sieve-based support is higher than the mass content of CoO supported on the hydroretrogenation catalyst. The components and contents of the obtained molecular sieve-based support B-2 are shown in Table 1, and the components and contents of the hydroretrogenation catalysts C-D2 are shown in Table 2.

[0085] Table 1. Composition and content of molecular sieve-based carriers

[0086]

[0087] Table 2 Composition and content of hydrotreating catalysts

[0088]

[0089]

[0090] Hydrogenation performance evaluation

[0091] The catalysts obtained in the examples and comparative examples were used to evaluate the performance of hydrogenation reactions. The hydrogenation reaction process conditions are as follows:

[0092] The catalyst was loaded into a 50 mL fixed isothermal bed reactor for reaction performance evaluation. Prior to evaluation, the hydrotreating catalyst underwent pre-sulfurization treatment using sulfurized oil. The treatment was conducted under a hydrogen-containing atmosphere, using straight-run gasoline as the sulfurized oil and dimethyl disulfide as the sulfurizing agent. During sulfurization, the catalyst bed temperature was increased at a rate of 20 °C / h and held at two temperature ranges of 230 °C and 280 °C for 8 hours. After the pre-sulfurization process was completed, the reaction operating conditions were adjusted to start-up conditions, and the sulfurized oil was switched to FCC full-range gasoline before entering the reaction stage. The reaction operating conditions were: inlet temperature 360 ​​°C, pressure 1.8 MPa, and volumetric hourly space velocity (VHSV) 2.5 h⁻¹. -1 The hydrogen-to-oil volume ratio is 400:1.

[0093] The hydrogenation reaction performance evaluation results of the catalysts obtained in the examples and comparative examples are shown in Table 3.

[0094] Table 3. Evaluation results of hydrogenation reaction performance of catalysts in the examples and comparative examples.

[0095] Catalyst name Desulfurization rate, % Isomer / aromatic conversion rate, % RON loss Liquid yield, % C-1 72.35 37.52 0.7 99.3 C-2 71.43 35.41 0.7 99.1 C-3 71.02 38.01 0.8 98.9 C-4 72.87 36.89 0.6 99.0 C-5 74.39 39.67 0.5 99.7 C-D1 70.51 34.66 1 98.1 C-D2 69.76 35.07 0.9 98.5

[0096] As can be seen from the results of Example 1 and Comparative Examples 1 and 2, the addition of an appropriate amount of cobalt-manganese solid solution to the molecular sieve-based support of the present invention can improve the desulfurization function, isomerization / aromatization conversion rate and gasoline liquid phase product yield, and reduce octane number loss.

[0097] Of course, the present invention may have other embodiments and variations. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and variations according to the present invention, but these corresponding changes and variations should all fall within the protection scope of the claims of the present invention.

Claims

1. A molecular sieve-based support, characterized in that, The molecular sieve-based support comprises 45-90 wt% molecular sieve, 0.1-5 wt% cobalt-manganese solid solution, and the balance alumina, based on 100% of the molecular sieve-based support. The cobalt-manganese solid solution includes at least one of CoMn2O4, Co2MnO4, CoMnO3, and Co2Mn3O8.

2. The molecular sieve-based support according to claim 1, characterized in that, The molecular sieve-based support comprises 55–85 wt% molecular sieve, 0.3–3 wt% cobalt-manganese solid solution, and the balance alumina.

3. The molecular sieve-based support according to claim 1, characterized in that, The molecular sieve is selected from one or more of ZSM-5, ZSM-22, ZSM-35, SAPO-11, mordenite, Y molecular sieve, and beta molecular sieve.

4. The molecular sieve-based support according to claim 1, characterized in that, The cobalt-manganese solid solution contains cubic Co2MnO4.

5. A method for preparing a molecular sieve-based support according to any one of claims 1-4, characterized in that, Specifically, the following steps are included: (1) Pretreatment of powder: Take cobalt-manganese solid solution with a particle size of less than 10 μm, molecular sieve and alumina powder are mixed, water is added and stirred to prepare slurry, the slurry is dispersed so that the particle size of the slurry is controlled below 5 μm; the slurry is separated into liquid and solid, and the solid is dried to obtain mixed powder containing cobalt-manganese solid solution; (2) Carrier molding: The mixed powder obtained in step (1) and the extrusion aid are dry mixed, and then mixed with the adhesive solvent and water and extruded into shape. (3) Heat treatment of the carrier: The carrier formed by extrusion is dried and calcined to obtain the molecular sieve-based carrier.

6. The preparation method according to claim 5, characterized in that, In step (3), the drying temperature is 100-150℃ and the drying time is 3-8 hours; the calcination temperature is 500-700℃ and the calcination time is 3-10 hours.

7. The preparation method according to claim 5, characterized in that, The molecular sieve is introduced in the following ways: it is added together with the cobalt-manganese solid solution and alumina powder during the mixing process; or the molecular sieve is added by dry powder mixing during the dry mixing process in step (2).

8. The preparation method according to claim 5, characterized in that, The adhesive solvent is an organic acid or an inorganic acid.

9. The preparation method according to claim 5, characterized in that, The adhesive solvent is at least one of oxalic acid, citric acid, nitric acid, and hydrochloric acid.

10. The preparation method according to claim 5, characterized in that, The extrusion aid is at least one of guar gum powder, starch, and methylcellulose.

11. A hydrogenation reforming catalyst, characterized in that, The catalyst comprises a Group VIB metal, a Group VIII metal, and a molecular sieve-based support as described in any one of claims 1-4. Based on 100 parts by weight of the catalyst component, the Group VIB metal is used in an amount of 0.5 to 10 parts by weight based on its oxide, the Group VIII metal is used in an amount of 0.1 to 5 parts by weight based on its oxide, and the molecular sieve-based support is used in an amount of 85 to 98 parts by weight. The Group VIII metal includes cobalt, and the cobalt content in the molecular sieve-based support is lower than the cobalt oxide content supported on the catalyst.

12. The catalyst according to claim 11, characterized in that, The amount of the group VIB metal oxide is 1 to 5 parts; the amount of the group VIII metal oxide is 0.2 to 3 parts; and the amount of the molecular sieve-based support is 88 to 95 parts.

13. The catalyst according to claim 11, characterized in that, The group VIB metal is tungsten and / or molybdenum; the group VIII metal is cobalt, or cobalt and nickel.

14. The catalyst according to claim 11, characterized in that, It also includes alkali metals or alkaline earth metals, wherein the alkali metals or alkaline earth metals are selected from at least one of Li, Na, K, Mg, and Ca; and the amount of the alkali metals or alkaline earth metals, calculated as oxides, is 0.5 to 5 parts per 100 parts by weight of the catalyst component.

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