A triflic acid rare earth solid carrier catalyst, a preparation method and application thereof

Abstract

The application discloses a trifluoromethanesulfonic acid rare earth solid carrier catalyst and a preparation method and application thereof, and belongs to the technical field of hydrofining catalyst preparation. The technical problems to be solved are that the reaction rate of a hydrofining catalyst system in a refining process is easily affected, PAHs are competitively adsorbed, and the catalyst is deactivated by initial carbon deposition. The technical solution is that a trifluoromethanesulfonic acid type rare earth complex is introduced into a Ni-Mo / Al2O3 metal system, so that the rare earth element and the metal precursor form a stable and highly dispersed composite system in a solution, and cooperatively participate in the structural evolution of a NiMoS active phase in a continuous process of impregnation, calcination and sulfidation, a solid carrier catalyst is prepared, and a rare earth reinforced NiMoS composite system with high metal dispersion, strong electronic regulation capacity and low deactivation kinetic constant is constructed, so that the deep hydrofining effect, the aromatic hydrocarbon saturation degree, the HDS efficiency and the operation stability are improved, and the application value is important.

Description

Technical Field

[0001] This invention relates to the field of hydrorefining catalyst preparation technology, and more specifically, to a rare earth supported catalyst for trifluoromethanesulfonic acid, its preparation method, and its application. Background Technology

[0002] The petrochemical industry is a vital pillar of the national economy and a major emitter of carbon dioxide. Currently, China's refining industry faces a development dilemma of overcapacity in low-end products and insufficient capacity in high-end products. Driven by the "dual carbon" target (carbon reduction and emission reduction), product structure adjustment in refineries is imperative. With global industrialization, the demand for clean middle distillate fuels is increasing worldwide. Hydrorefining technology is one of the core steps in modern refining processes. Its purpose is to remove sulfur, nitrogen, and metallic impurities from diesel and other middle distillates, and to hydrogenate and saturate polycyclic aromatic hydrocarbons, thereby significantly improving the cetane number and combustion quality of the fuel, reducing sulfur content, improving combustion performance, and reducing exhaust pollution. Due to its excellent hydrodesulfurization (HDS) behavior after sulfidation, bimetallic Ni-Mo / γ-Al2O3 catalysts have been widely used in diesel hydrorefining processes since the 1940s. Ni-Mo catalysts mainly consist of a γ-Al2O3 support and the supported sulfidated active metals Ni and Mo. Typically, industrially widely used hydrorefining catalysts utilize γ-Al₂O₃ as a support, loaded with approximately 20% Ni-Mo or Co-Mo active metal components by mass. γ-Al₂O₃ is considered an excellent hydrorefining catalyst support due to its large specific surface area, pore volume, and suitable acidic sites. The metal is calcined to form an oxidized precursor, which is then subjected to sulfidation to generate NiMoS or CoMoS lamellar structures with high hydrorefining reactivity. The edge sulfidation sites are considered the main active centers for hydrodesulfurization, hydrodenitrogenation, and aromatic saturation reactions. Hydrorefining kinetic studies from the literature indicate that aromatic hydrogenation is a typical reversible reaction, and its reaction rate is influenced by hydrogen partial pressure, temperature, liquid hourly space velocity, and competitive adsorption of multiple components. Especially when the blending ratio of heavy diesel or FCC diesel is high, the competitive adsorption of PAHs inhibits the smooth progress of the hydrogenation reaction and accelerates the initial deactivation of the catalyst due to carbon deposition.

[0003] With the increasing stringent quality standards for diesel fuel, such as the strict limits on aromatic and sulfur content imposed by China's National VI and Euro VI standards, the performance of traditional Ni-Mo hydrorefining catalysts is facing multiple challenges: high concentrations of PAHs make it difficult for the hydrogenation reaction to proceed completely; competitive adsorption between aromatics and sulfides delays the complete formation of the metal sulfide phase; and the large amount of carbon deposits in the early stages of the reaction leads to a rapid reduction in the active edge sites of NiMoS. In liquid-phase diesel systems, the aromatic hydrogenation capacity of Ni-Mo catalysts is closely related to the degree of metal sulfidation, metal dispersion, and pore diffusion characteristics. The rapid deactivation of the catalyst in the first 10–30 hours of the reaction is mostly due to the polymerization and carbonization of PAHs, pore narrowing, and the covering of edge sites.

[0004] Since all hydrorefining reactions occur on the catalyst surface, the catalyst constitutes the core of the process. Developing efficient and suitable catalysts is the key to solving the problem. Research mainly focuses on catalyst support structure, acidity regulation, and the stability of metal sulfide phases. The field of hydrorefining catalysis is constantly evolving and developing.

[0005] Currently, in the field of catalyst support research, the use of TiO2-modified γ-Al2O3 as a support for Ni-Mo hydrogenation catalysts has been proven to significantly improve the surface properties, low-temperature sulfidation performance, and hydrogenation activity of the catalyst. Beyond traditional techniques, rare earth elements, due to their unique 4f electron structure, redox buffering capacity, and electronic modulation effect on metal centers, have begun to be used to improve the stability of the metal sulfide phase and resistance to carbon deposition in hydrogenation catalytic systems. Studies have shown that rare earth elements can enhance the hydrogenation saturation capacity of aromatics by adjusting the electron density of metal sulfides, thus facilitating the dissociation and adsorption activation processes of hydrogen molecules. Simultaneously, rare earth oxides often exhibit moderate Lewis acidity, which helps to suppress excessive cracking caused by overly acidic supports, making the hydrogenation reaction more selective and efficient.

[0006] Relevant patent documents retrieved: This document, published in China (CN110404527A) on November 5, 2019, discloses a hydrodesulfurization catalyst, its preparation method, and its application. The hydrodesulfurization catalyst prepared in this document comprises a modified catalyst support and a supported active metal. The modified catalyst support is either a rare-earth element-modified γ-Al₂O₃ support, or a composite support prepared by calcining γ-Al₂O₃ and acidic molecular sieves with a binder, followed by rare-earth element modification. The hydrodesulfurization catalyst prepared in this document can achieve deep desulfurization of high-sulfur catalytic cracking gasoline under relatively mild conditions. However, this document is primarily intended for deep desulfurization of high-sulfur gasoline to ensure minimal loss of octane number and is not suitable for refining diesel fuel with high boiling points, high levels of metallic impurities, high nitrogen content, and high levels of polycyclic aromatic hydrocarbons.

[0007] This document, published in China (CN104117362A) on March 6, 2018, discloses a catalyst and its preparation method for improving the hydrogenation activity of a NiMo diesel hydrorefining catalyst. It utilizes an alumina support, a metal component with diesel hydrodesulfurization activity, an organic chelate, and a certain amount of water, and prepares the catalyst through heating, air drying, calcination, and pre-sulfurization treatment. The document improves the hydrogenation activity of the catalyst by controlling the catalyst preparation process and parameters, particularly the preparation process of the citric acid bimetallic complex precursor solution.

[0008] In solving the above problems or overcoming the above defects, the present invention encountered the following difficulties and obstacles: In the process of improving the existing Ni-Mo hydrorefining catalyst system, simply increasing the metal loading and changing the calcination or sulfidation conditions cannot fundamentally solve the problem of competitive adsorption of polycyclic aromatic hydrocarbons and nitrogen-containing compounds on active sites in the early stage of the reaction. In addition, it is easy to cause metal species agglomeration or damage to the pore structure of the support, which leads to a decrease in catalyst stability.

[0009] When attempting to introduce rare earth elements to improve catalyst performance, problems arise such as the limited solubility of rare earth precursors in aqueous or mixed solvent systems, and their susceptibility to hydrolysis or precipitation. This leads to uneven distribution of rare earth species on the support surface, making it difficult to form a stable synergistic relationship with Ni and Mo precursors. Furthermore, if rare earth species participate improperly during calcination and sulfidation, they may interfere with the normal formation of the NiMoS active phase, thereby weakening hydrogenation activity.

[0010] Therefore, in the preparation of hydrorefining catalysts, ensuring high dispersion of Ni and Mo precursors while effectively controlling the electronic structure of the metal sulfide phase and the acidity of the support by rare earth elements is a key technical challenge. If the metal complex system lacks stability, component migration or local enrichment can easily occur during impregnation and drying, thus affecting the evolution of the active phase structure in the subsequent sulfidation process. Since hydrorefining reactions are typically carried out at high temperatures and hydrogen partial pressures, the catalyst is highly susceptible to carbon deposition and deactivation in the early stages of the reaction. Improving the catalyst's resistance to carbon deposition and initial operational stability without significantly increasing process complexity and cost is a crucial practical engineering obstacle that this invention needs to overcome in its implementation. Summary of the Invention

[0011] The purpose of this invention is to provide: A rare earth supported catalyst for trifluoromethanesulfonic acid, its preparation method and application, and related technologies, to solve technical problems such as the susceptibility of reaction rate to adverse effects in hydrorefining catalyst systems during oil refining processes, competitive adsorption of PAHs, and initial deactivation of catalysts due to carbon deposition, or combinations thereof.

[0012] Terminology Explanation: Unless otherwise defined, all technical terms in this document have the same meanings as commonly understood by one of ordinary skill in the art to which the subject matter of the claims pertains. Unless otherwise stated, all patents, patent inventions, and publications cited in this document are incorporated herein by reference in their entirety. If multiple definitions exist for terms in this document, the definitions in this chapter shall prevail.

[0013] It should be understood that the above brief description and the following detailed description are exemplary and for illustrative purposes only, and do not limit the subject matter of the invention in any way. In this invention, the singular is used in conjunction with the plural unless otherwise specifically stated. It should also be noted that, unless otherwise stated, the use of “or” or “or” means “and / or”. Furthermore, the use of the term “comprising” and other forms such as “including,” “containing,” and “contains” are not limiting.

[0014] Unless otherwise stated, conventional methods within the scope of the art, such as diesel hydrorefining microreactor test and heavy VGO hydrorefining test, shall be used.

[0015] Unless specifically defined herein, the use of all commercially available products herein employs standard techniques. For example, it may be carried out using the manufacturer's instructions for use with the kit, or in accordance with methods known in the art or the description of this invention. The techniques and methods described herein can generally be implemented according to conventional methods well known in the art, based on the descriptions in the various summary and more specific documents cited and discussed in this specification.

[0016] The term "hydrorefining" used in this article refers to a core process in the petroleum refining and chemical industry that deeply enhances the quality of various petroleum products or chemical feedstocks, such as gasoline, diesel, and vacuum gas oil (VGO), under high temperature and hydrogen partial pressure and the action of transition metal supported catalysts such as Co-Mo / Ni-Mo. The core principle is to remove harmful impurities such as sulfur, nitrogen, and oxygen from the feedstock through a series of catalytic hydrogenation reactions (converting them to H2S, NH3, and H2O, respectively), unsaturated bonds such as saturated olefins and aromatics (converting them to alkanes and cycloalkanes), and trace metal impurities (such as Ni and V in VGO) and gums. Ultimately, this achieves the goal of "reducing impurities, improving stability, and optimizing performance"—meeting environmental regulations' requirements for low sulfur and low nitrogen content, avoiding equipment corrosion, downstream catalyst poisoning, and pollutant emissions caused by impurities, while also improving product performance (such as diesel cetane number and gasoline stability). This provides high-quality feedstocks / products for subsequent processing or direct use, and is a crucial step in the production of clean fuels, high-end chemical feedstocks, and lubricating oil base oils.

[0017] The term "vacuum gas oil (VGO)" used in this article refers to Vacuum Gas Oil, abbreviated as VGO. It is a heavy middle distillate oil obtained by distilling the remaining atmospheric residue oil under reduced pressure (1-5 kPa) after separating light fractions such as gasoline and diesel through atmospheric distillation in crude oil atmospheric vacuum distillation unit, in order to avoid high-temperature cracking or coking. Its distillation range is about 350-550℃, and the molecular carbon number is mostly C18-C30. It is mainly composed of long-chain alkanes, cycloalkanes and bicyclic / polycyclic aromatic hydrocarbons. It has a high gum content and contains a certain amount of sulfur and nitrogen impurities and trace metals (Ni, V). At room temperature, it is a dark brown viscous liquid. As a core intermediate raw material in the petroleum refining industry chain, VGO is mainly used in deep processing processes such as hydrocracking and catalytic cracking to be converted into high-quality diesel, aviation kerosene, gasoline blending components and chemical raw materials (such as naphtha). Some high-quality VGO can also be used as heavy diesel blending components or high-grade lubricating oil base oil raw materials after hydrorefining or isomerization and dewaxing. It is a key link connecting crude oil primary processing with the production of clean fuels and high-end chemical products.

[0018] The term "hydrodesulfurization" used in this article refers to Hydrodesulfurization, abbreviated as HDS. HDS is a deep desulfurization process used in the petroleum refining and chemical industries. Under high temperature and pressure, in a hydrogen atmosphere, and with the action of a transition metal supported catalyst, sulfur-containing compounds (such as thiophene, dibenzothiophene, thiols, sulfides, etc.) in the feedstock undergo a catalytic reaction with hydrogen, converting sulfur atoms into hydrogen sulfide (H2S) while retaining or converting the hydrocarbon skeleton into the corresponding alkanes / cycloalkanes. Its core purpose is to remove harmful sulfur impurities from the feedstock, reduce the sulfur content of the product to meet environmental regulations, and simultaneously avoid sulfur corrosion of downstream equipment, catalyst poisoning, and sulfur dioxide emissions during combustion. HDS is widely used in the refining of various oil products such as gasoline, diesel, and vacuum gas oil (VGO), and is one of the key technologies for producing clean fuels and high-end chemical raw materials.

[0019] The term "sulfidation treatment" as used in this article refers to the process of treating hydrogenation catalysts (such as Co-Mo / Al2O3, Ni-Mo / Al2O3) in a mixed atmosphere of sulfur-containing media (such as H2S, carbon disulfide, sodium thiosulfate solution) and hydrogen under specific temperature (usually 200-400℃) and pressure conditions before use or during the reaction. Its core purpose is to convert the oxidized active metals (such as CoO, MoO3) in the catalyst into catalytically active sulfide species (such as MoS2, Co9S8) to meet the catalytic requirements of hydrogenation reactions such as hydrodesulfurization and hydrodenitrogenation.

[0020] The term "deep cracking reaction" used in this article refers to a reaction process in which, under catalytic or thermal conversion conditions, the C-C bonds of heavy hydrocarbons (such as vacuum gas oil and residual oil) break, generating hydrocarbon products with smaller molecular weights and lighter distillation ranges (such as gasoline, diesel, and liquefied petroleum gas), and the cracking depth is higher than that of conventional light cracking. Its characteristics include high conversion rate (usually >50%), a significantly increased proportion of light fractions in the products, and possible secondary reactions such as cycloalkanes ring opening and aromatic side chain breaking.

[0021] The term "anti-coking effect" used in this article refers to the ability of a catalyst to inhibit the adsorption and deposition of coke (mainly insoluble carbon deposits formed by the polymerization and dehydrogenation of unsaturated hydrocarbons) on the catalyst surface during catalytic reactions (especially reactions that easily produce coke, such as hydrocarbon conversion and hydrorefining). This is achieved through the regulation of the catalyst's own structural characteristics (such as suitable pore size, acid center strength and distribution) or active components, thereby maintaining the exposure of the catalyst's active sites and long-term catalytic stability, and reducing catalyst deactivation caused by coking.

[0022] The term "stepwise impregnation method" used in this article refers to a preparation method in which a support (such as γ-Al2O3 or mesoporous SiO2) is contacted, adsorbed, dried, and calcined with impregnation solutions (such as metal salt solutions) containing different active components in multiple steps during the preparation of supported catalysts. Each impregnation loads only one or a portion of the active components. By controlling parameters such as concentration, time, and pH value of each impregnation step, the uniform dispersion and precise control of multiple active components on the surface of the support can be achieved, avoiding the agglomeration or uneven distribution of active components caused by a single impregnation.

[0023] The term "weak Lewis acid center" used in this article refers to an active site on the catalyst surface that has the ability to accept electron pairs but has relatively weak acid strength (usually determined by characterization methods such as NH3-TPD and Py-IR, corresponding to an NH3 desorption peak temperature <300℃ or a Py-IR peak temperature of 1450 cm⁻¹). - ¹The intensity of the characteristic peaks near the catalyst is relatively weak. Their formation is related to the interaction between unsaturated coordinated metal ions, defect sites, or metal-support on the catalyst surface. In the catalytic reaction, they mainly participate in the adsorption, polarization, and mild electron transfer processes of weakly polar molecules. They can improve the selectivity of the reaction while inhibiting side reactions such as excessive cracking and carbon deposition.

[0024] The term "mixing" as used in this article refers to the process of combining two or more different substances (which may be solid, liquid, gas, or a combination of different states) through physical or mechanical means to form a macroscopically homogeneous or relatively homogeneous dispersion system.

[0025] The term "stirring" as used in this article refers to the operation of mixing multiple substances evenly by means of machinery or manual agitation. Specifically, it refers to the process of creating flow in a container with the help of external forces (such as rotating blades, stirring rods, airflow, etc.) to achieve uniform mixing of solids, liquids, or gases.

[0026] As used in this article, the term “selected from” means: one or more elements from the groups listed below, selected independently, and may include combinations of two or more elements.

[0027] In a first aspect, the present invention provides: a method for preparing a rare earth trifluoromethanesulfonic acid supported catalyst, characterized in that a rare earth trifluoromethanesulfonic acid complex is directly introduced into a Ni-Mo system to obtain a metal complex system solution, then the catalyst support is modified by the metal complex system, and then a solid precursor powder is obtained by depressurization and drying, so that the rare earth-Ni-Mo composite precursor is successfully loaded on the catalyst support, and finally the solid precursor powder is calcined and sulfided to prepare a rare earth trifluoromethanesulfonic acid supported catalyst. The rare earth trifluoromethanesulfonate complexes are selected from lanthanum trifluoromethanesulfonate, cerium trifluoromethanesulfonate, lutetium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, or samarium trifluoromethanesulfonate. The mass ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complex is 1-3:25-50.

[0028] Preferably, the rare earth trifluoromethanesulfonate complex is lanthanum trifluoromethanesulfonate or cerium trifluoromethanesulfonate.

[0029] Preferably, the catalyst support is γ-Al2O3.

[0030] Preferably, the mass ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complex is selected from any value or range between 1-3:25-50; More preferably, the mass ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complex is selected from any value or range between 1-3:25-50, specifically from: 1:25, 1:35, 1:45, 1:50, 2:25, 2:35, 3:45, 3:50 or any two of them; More preferably, the mass ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complex is selected from any value or range between 1-3:25-50, specifically from: 1:25, 3:50, 1:50 or any two of them; More preferably, the mass ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complex is 3:50.

[0031] As a preferred embodiment, the method for preparing the metal complex system solution includes the following steps: (1.1) Weigh out the rare earth trifluoromethanesulfonic acid complex and add it to ethanol. Stir and dissolve to obtain solution 1; (1.2) Weigh out ammonium heptamolybdate and nickel nitrate hexahydrate, dissolve them in water, and then add citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 to form a metal complex system solution.

[0032] Preferably, the ethanol mentioned in step (1.1) is anhydrous ethanol.

[0033] Preferably, the mass and volume of the trifluoromethanesulfonic acid rare earth complex and ethanol in step (1.1) are selected from any value or range between 1g:50-100mL; More preferably, the mass and volume of the trifluoromethanesulfonic acid rare earth complex and ethanol in step (1.1) are selected from any value or range between 1g:50-70mL, specifically from: 1g:50mL, 1g:55mL, 1g:60mL, 1g:65mL, 1g:70mL, 1g:75mL, 1g:80mL, 1g:85mL, 1g:90mL, 1g:1000mL or any range between two of them; More preferably, the mass and volume of the trifluoromethanesulfonic acid rare earth complex and ethanol in step (1.1) are selected from any value or range between 1g:50-70mL, specifically from: 1g:50mL, 1g:100mL, or any range between the two. More preferably, the mass-volume ratio of the trifluoromethanesulfonic acid rare earth complex and ethanol in step (1.1) is 1 g: 30 mL.

[0034] Preferably, the specific operation of stirring and dissolving in step (1.1) is to completely dissolve the trifluoromethanesulfonic acid rare earth complex in anhydrous ethanol until a transparent solution is obtained.

[0035] Preferably, the mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is selected from any value or range between 1.5-2.5:0.8-1.5; More preferably, the mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is selected from any value or range between 1.8-2.4:0.9-1.2.

[0036] Preferably, the mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is selected from any value or range between 1.8-2.4:0.9-1.2, specifically from: 1.8:0.9, 2.0:1.0, 2.2:1.1, 2.4:1.2 or any two of them; More preferably, the mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is selected from any value or range between 1.8-2.4:0.9-1.2, specifically from: 2.40:1.2, 1.8:0.9 or any two of them; More preferably, the mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is 1.8:0.9.

[0037] Preferably, the water in step (1.2) is deionized water.

[0038] Preferably, the volume of deionized water added in step (1.2) is 30 mL.

[0039] Preferably, the amount of citric acid added in step (1.2) is 1.2-1.8 times the total molar amount of metal.

[0040] Preferably, the stirring time in step (1.3) is selected from any value or range between 20 and 30 minutes; More preferably, the stirring time in step (1.3) is selected from any value or range between 20 and 30 min, specifically from: 20 min, 25 min, 30 min or any two of them; More preferably, the stirring time in step (1.3) is 20 minutes.

[0041] As the most preferred embodiment, the method for preparing the metal complex system solution includes the following steps: (1.1) Weigh 0.60 g of lanthanum trifluoromethanesulfonate and add it to 30 mL of anhydrous ethanol and stir until completely dissolved to obtain solution 1; (1.2) Weigh 3.6g of ammonium heptamolybdate and 1.8g of nickel nitrate hexahydrate and dissolve them in 45mL of deionized water, then add 1.8g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 20 minutes to obtain the metal complex system solution.

[0042] As a preferred embodiment, the method for preparing the solid precursor powder includes the following steps: (2.1) After drying the catalyst support, store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in step (1.3) into the catalyst support prepared in step (2.1), let it stand, and obtain material 1; (2.3) Reduce the pressure and dry the material 1 to obtain solid precursor powder.

[0043] Preferably, the drying temperature in step (2.1) is 120°C.

[0044] Preferably, the drying time in step (2.1) is 4 hours.

[0045] Preferably, the specific operation described in step (2.2) is as follows: the metal complex system solution prepared in step (1.3) is slowly immersed into γ-Al2O3 using the equal volume impregnation method, so that the pores of the support are completely wetted and kept still, so that Ni, Mo and La can fully enter the pores of the catalyst support and be uniformly adsorbed on the surface.

[0046] Preferably, the settling time in step (2.2) is selected from any value or range between 30 and 60 minutes; More preferably, the settling time in step (2.2) is selected from any value or range between 30 and 60 minutes, specifically from: 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes or any two of them; More preferably, the settling time in step (2.2) is selected from any value or range between 30 and 60 minutes, specifically from 40 minutes, 45 minutes, 60 minutes or any two of them; More preferably, the settling time in step (2.2) is 60 minutes.

[0047] Preferably, the temperature for decompression in step (2.3) is selected from any value or range between 50-70°C; More preferably, the decompression temperature in step (2.3) is selected from any value or range between 50-70℃, specifically from: 50℃, 55℃, 60℃, 65℃, 70℃ or any two of them; More preferably, the temperature for decompression in step (2.3) is selected from any value or range between 50-70°C, specifically from: 50°C, 60°C, 70°C or any two of them; More preferably, the decompression temperature in step (2.3) is 50°C.

[0048] Preferably, the decompression time in step (2.3) is 30-60 minutes.

[0049] Preferably, the drying in step (2.3) consists of a first drying and a second drying.

[0050] Preferably, the temperature for the first drying step (2.3) is selected from any value or range between 80-90°C; More preferably, the temperature of the first drying step (2.3) is selected from any value or range between 80-90℃, specifically from: 80℃, 81℃, 82℃, 83℃, 84℃, 85℃, 86℃, 87℃, 88℃, 89℃, 90℃ or any two of them; More preferably, the temperature of the first drying step (2.3) is selected from any value or range between 80-90℃, specifically from: 80℃, 90℃ or any range between the two; More preferably, the temperature of the first drying step (2.3) is 90°C.

[0051] Preferably, the drying time for the first drying step (2.3) is selected from any value or range between 10 and 12 hours; More preferably, the first drying time in step (2.3) is selected from any value or range between 10-12h, specifically from 10h, 10.5h, 11h, 11.5h, 12h or any two of them; More preferably, the first drying time in step (2.3) is selected from any value or range between 10-12h, specifically from 10h, 12h or any range between the two; More preferably, the first drying time in step (2.3) is 10 hours.

[0052] Preferably, the temperature for the second drying step (2.3) is selected from any value or range between 110-120°C; More preferably, the temperature of the second drying in step (2.3) is selected from any value or range between 110-120℃, specifically from: 110℃, 111℃, 112℃, 113℃, 114℃, 115℃, 116℃, 117℃, 118℃, 119℃, 120℃ or any two of them; More preferably, the temperature of the second drying in step (2.3) is selected from any value or range between 110-120℃, specifically from: 110℃, 120℃ or any range between the two; More preferably, the temperature of the second drying in step (2.3) is 110°C.

[0053] Preferably, the second drying time in step (2.3) is selected from any value or range between 4 and 5 hours; More preferably, the second drying time in step (2.3) is selected from any value or range between 4 and 5 hours, specifically from 4 hours, 5 hours or any two of them. More preferably, the second drying time in step (2.3) is 5 hours.

[0054] Preferably, the environment for the second drying in step (2.3) is a vacuum environment.

[0055] Preferably, the calcination is carried out at a temperature increase of 2°C / min.

[0056] Preferably, the calcination temperature is selected from any value or range between 480-500℃; More preferably, the roasting temperature is selected from any value or range between 480-500℃, specifically from: 480℃, 481℃, 482℃, 483℃, 484℃, 485℃, 486℃, 487℃, 488℃, 489℃, 490℃, 491℃, 492℃, 493℃, 494℃, 495℃, 496℃, 497℃, 498℃, 499℃, 500℃ or any two of them. More preferably, the roasting temperature is selected from any value or range between 480-500℃, specifically from: 480℃, 485℃, 489℃, 490℃, 491℃, 495℃, 499℃, 500℃ or any two of them; More preferably, the calcination temperature is selected from any value or range between 480-500℃, specifically from: 480℃, 490℃, 500℃ or any two of them; More preferably, the roasting temperature is 500°C.

[0057] Preferably, the roasting time is 4 hours.

[0058] Preferably, the hydrogen partial pressure of the sulfidation is selected from any value or range between 6.0 and 8.0 MPa; More preferably, the hydrogen partial pressure of the sulfidation is selected from any value or range between 6.0 and 8.0 MPa, specifically from: 6.0 MPa, 7.0 MPa, 8.0 MPa or any two of them; More preferably, the hydrogen partial pressure of the sulfidation is 7.0 MPa.

[0059] Preferably, the vulcanization time is 12 hours.

[0060] Secondly, the present invention provides a rare earth-supported trifluoromethanesulfonic acid catalyst prepared by the above preparation method.

[0061] Thirdly, the present invention provides the application of the above-mentioned trifluoromethanesulfonic acid rare earth supported catalyst in diesel processing, wherein the diesel processing is one or more of the following: reducing the sulfur / nitrogen content of diesel, increasing the cetane number, improving combustion performance, and causing hydrogenation saturation of polycyclic aromatic hydrocarbons.

[0062] Fourthly, the present invention provides the application of the above-mentioned trifluoromethanesulfonic acid rare earth supported catalyst in the processing of heavy distillate oil, wherein the processing of heavy distillate oil is one or more of the following: reducing the sulfur / nitrogen content of diesel oil, increasing the cetane number, improving combustion performance, and causing hydrogenation saturation of polycyclic aromatic hydrocarbons.

[0063] Based on further solutions to the technical problems of the present invention, or simultaneous solutions to multiple technical problems, the preferred solution in the technical solution provided in the first aspect of the present invention includes: The first preferred option is a method for preparing a rare earth supported catalyst for trifluoromethanesulfonic acid. This technical solution not only solves the technical problem of "poor desulfurization and denitrification efficiency", but also further solves the technical problems of "poor hydrogenation saturation and poor initial stability of polycyclic aromatic hydrocarbons".

[0064] The beneficial effects of this invention are as follows: The present invention has at least the following beneficial effects: 1. The rare earth trifluoromethanesulfonic acid complex forms a special electronic coupling and dispersion synergy with the Ni-Mo active phase, which makes the NiMoS structure exhibit higher edge sulfidation, faster hydrogenation reaction path initiation rate, and stronger anti-carbon deposition ability.

[0065] 2. Regardless of whether it is light diesel or heavy VGO feedstock, the catalyst prepared in this application can quickly reach a stable reaction state and maintain high selectivity and high conversion rate for a long time.

[0066] 3. The regulation effect of rare earth elements on the acidity of the support reduces excessive cracking, keeps the product yield stable, and keeps hydrogen consumption at a low level.

[0067] 4. The catalyst prepared by this invention can reduce the sulfur content to single digits ppm, which significantly exceeds the range achievable by traditional Ni-Mo catalysts; in the HDN reaction, its nitrogen removal capacity is also significantly enhanced, and rare earth elements have unique advantages in the electron-promoting effect of nitrogen species hydrogenation cracking process.

[0068] 5. This invention introduces a rare earth trifluoromethanesulfonic acid complex into the traditional Ni-Mo hydrorefining catalyst system, thereby constructing a rare earth-enhanced NiMoS composite system with higher metal dispersion, stronger electronic regulation capability, and lower loss of mobility. This significantly improves its performance in deep hydrorefining, aromatic saturation, HDS efficiency, and operational stability, and has great engineering application value.

[0069] Furthermore, based on the present invention: 1. Based on the comparison of Examples 1-6 and Comparative Examples 1-6, the present invention purposefully selects a narrow-range trifluoromethanesulfonic acid rare earth complex that is not mentioned in the prior art from the broad range of rare earth complexes disclosed in the prior art, and introduces it into the Ni-Mo system to obtain a metal complex system solution. The Ni and Mo precursors can be stably dispersed in the metal complex system solution, and the formation of a more uniform and highly dispersed NiMoS active phase is promoted during the calcination and sulfidation process, achieving unexpected technical effects. Attached Figure Description

[0070] Figure 1 The results are from the microreactor test of diesel hydrorefining in Example 1.

[0071] Figure 2 The results are from the hydrogenation purification test of heavy VGO in Example 6. Detailed Implementation

[0072] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection claimed by the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and such changes should also fall within the scope of protection claimed by the present invention.

[0073] The present invention will be further described below by way of specific embodiments. Unless otherwise specified, all instruments, devices, equipment, reagents, products, etc., used in the embodiments of the present invention are obtained through conventional commercial means.

[0074] Basic Example 1-1 Preparation of Metal Complex System Solution The preparation method is as follows: (1.1) Weigh 0.40 g of lanthanum trifluoromethanesulfonate and add it to 20 mL of anhydrous ethanol and stir until completely dissolved to obtain solution 1; (1.2) Weigh 2.40g of ammonium heptamolybdate and 1.20g of nickel nitrate hexahydrate and dissolve them in 30mL of deionized water, then add 1.20g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 20 minutes to obtain the metal complex system solution.

[0075] Preparation of metal complex system solutions in basic examples 1-2 The preparation method is as follows: (1.1) Weigh 0.60 g of lanthanum trifluoromethanesulfonate and add it to 30 mL of anhydrous ethanol and stir until completely dissolved to obtain solution 1; (1.2) Weigh 3.60g of ammonium heptamolybdate and 1.80g of nickel nitrate hexahydrate and dissolve them in 45mL of deionized water, then add 1.80g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 20 minutes to obtain the metal complex system solution.

[0076] Preparation of metal complex system solutions in basic examples 1-3 The preparation method is as follows: (1.1) Weigh 0.20 g of lanthanum trifluoromethanesulfonate and add it to 20 mL of anhydrous ethanol and stir until completely dissolved to obtain solution 1; (1.2) Weigh 1.20g of ammonium heptamolybdate and 0.60g of nickel nitrate hexahydrate and dissolve them in 20mL of deionized water, then add 0.60g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 20 minutes to obtain the metal complex system solution.

[0077] Preparation of metal complex system solutions in basic examples 1-4 The preparation method is as follows: (1.1) Weigh 0.40 g of cerium trifluoromethanesulfonate and add it to 20 mL of anhydrous ethanol. Stir until completely dissolved to obtain solution 1; (1.2) Weigh 2.40g of ammonium heptamolybdate and 1.20g of nickel nitrate hexahydrate and dissolve them in 30mL of deionized water, then add 1.20g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 30 minutes to obtain the metal complex system solution.

[0078] Preparation of metal complex system solutions in basic examples 1-5 The preparation method is as follows: (1.1) Weigh 0.60 g of cerium trifluoromethanesulfonate and add it to 30 mL of anhydrous ethanol. Stir until completely dissolved to obtain solution 1; (1.2) Weigh 3.60g of ammonium heptamolybdate and 1.80g of nickel nitrate hexahydrate and dissolve them in 45 mL of deionized water, then add 1.80g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 30 minutes to obtain the metal complex system solution.

[0079] Preparation of metal complex system solutions in Basic Examples 1-6 The preparation method is as follows: (1.1) Weigh 0.20 g of cerium trifluoromethanesulfonate and add it to 20 mL of anhydrous ethanol. Stir until completely dissolved to obtain solution 1; (1.2) Weigh 2.40g of ammonium heptamolybdate and 1.20g of nickel nitrate hexahydrate and dissolve them in 30mL of deionized water, then add 1.20g of citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 for 30 minutes to obtain the metal complex system solution.

[0080] Basic Comparative Example 1-1 The difference from the basic examples 1-2 is that the trifluoromethanesulfonic acid rare earth complex is not introduced, specifically step (1.1) is omitted, and the remaining steps are the same as those in the basic examples 1-2.

[0081] Basic Comparative Example 1-2 The difference from basic Examples 1-2 is that the mass of ammonium heptamolybdate and nickel nitrate hexahydrate is changed, wherein the mass of ammonium heptamolybdate is 1.40g and the mass of nickel nitrate hexahydrate is 1.60g, and the remaining steps are the same as those in basic Examples 1-2.

[0082] Basic Comparison Examples 1-3 The difference from basic Examples 1-2 is that the mass of ammonium heptamolybdate and nickel nitrate hexahydrate is changed, wherein the mass of ammonium heptamolybdate is 3.60g and the mass of nickel nitrate hexahydrate is 0.6g, and the remaining steps are the same as those in basic Examples 1-2.

[0083] Basic Comparative Examples 1-4 The difference from the basic examples 1-6 is that the mass of ammonium heptamolybdate and nickel nitrate hexahydrate is changed, wherein the mass of ammonium heptamolybdate is 1.40g and the mass of nickel nitrate hexahydrate is 1.60g, and the remaining steps are the same as those in the basic examples 1-6.

[0084] Basic Comparison Examples 1-5 The difference from the basic examples 1-6 is that the mass of ammonium heptamolybdate and nickel nitrate hexahydrate is changed, wherein the mass of ammonium heptamolybdate is 3.60g and the mass of nickel nitrate hexahydrate is 0.60g, and the remaining steps are the same as those in the basic examples 1-6.

[0085] Basic Example 2-1 Preparation of Solid Precursor Powder The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in Basic Example 1-1 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 40 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 80°C for 12 hours, and then dried for the second time at 120°C in a vacuum for 4 hours to obtain solid precursor powder.

[0086] Basic Example 2-2 Preparation of Solid Precursor Powder The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in Basic Examples 1-2 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 60 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 50°C, it is dried for the first time at 90°C for 10 hours, and then dried for the second time at 110°C in a vacuum for 5 hours to obtain solid precursor powder.

[0087] Basic Examples 2-3 Preparation of Solid Precursor Powder The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in basic Examples 1-3 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 60 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 70°C, it is dried for the first time at 90°C for 10 hours, and then dried for the second time at 110°C in a vacuum for 5 hours to obtain solid precursor powder.

[0088] Basic Examples 2-4 Preparation of Solid Precursor Powder The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in basic Examples 1-4 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 45 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 80°C for 12 hours, and then dried for the second time at 120°C in a vacuum for 4 hours to obtain solid precursor powder.

[0089] Basic Examples 2-5 Preparation of Solid Precursor Powder The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in basic Examples 1-5 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 45 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 80°C for 12 hours, and then dried for the second time at 120°C in a vacuum for 4 hours to obtain solid precursor powder.

[0090] Preparation of solid precursor powders in Basic Examples 2-6 The preparation method is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 10.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in Basic Examples 1-6 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 45 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 80°C for 12 hours, and then dried for the second time at 120°C in a vacuum for 4 hours to obtain solid precursor powder.

[0091] Basic Comparative Example 2-1 The difference from the basic embodiment 2-2 is that the metal complex system solution in step (2.2) is changed, specifically: (2.2) The metal complex system solution prepared in basic comparative example 1-1 was immersed in the γ-Al2O3 catalyst support prepared in step (2.1) and allowed to stand for 40 min to obtain material 1; The remaining steps are the same as in the basic embodiment 2-2.

[0092] Basic Comparative Example 2-2 The difference from the basic embodiment 2-2 is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 9.0g and store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in basic comparative examples 1-2 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 40 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 70°C for 14 hours, and then dried for the second time in air at 110°C for 6 hours to obtain solid precursor powder. Basic Comparison Example 2-3 The difference from the basic embodiment 2-2 is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 6.5g and store it under nitrogen protection. (2.2) The metal complex system solution prepared in basic comparative examples 1-3 was immersed in the γ-Al2O3 catalyst support prepared in step (2.1) and allowed to stand for 40 min to obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 100°C for 9 hours, and then dried for the second time in air at 130°C for 3.5 hours to obtain solid precursor powder. Basic Comparative Examples 2-4 The difference from the basic embodiments 2-6 is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 9.0g and store it under nitrogen protection for later use; (2.2) The metal complex system solution prepared in basic comparative examples 1-4 was immersed in the γ-Al2O3 catalyst support prepared in step (2.1) and allowed to stand for 40 min to obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 70°C for 14 hours, and then dried for the second time in air at 110°C for 6 hours to obtain solid precursor powder. Basic Comparison Examples 2-5 The difference from the basic embodiments 2-6 is as follows: (2.1) After drying the γ-Al2O3 catalyst support at 120℃ for 4h, weigh 6.5g and store it under nitrogen protection. (2.2) Immerse the metal complex system solution prepared in basic comparative examples 1-5 into the γ-Al2O3 catalyst support prepared in step (2.1), let it stand for 40 min, and obtain material 1; (2.3) After removing the solvent from material 1 under reduced pressure at 60°C, it is dried for the first time at 100°C for 9 hours, and then dried for the second time in air at 130°C for 3.5 hours to obtain solid precursor powder.

[0093] Example 1: Preparation of rare earth supported catalyst of trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in Basic Example 2-1 was calcined in air at 2℃ / min to 480℃ for 4h, and then added to white oil containing 2wt%CS2 and sulfided at 6.0MPa hydrogen pressure for 12h.

[0094] Example 2: Preparation of rare earth supported catalysts for trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in Basic Example 2-2 was calcined in air at 2℃ / min to 500℃ for 4h, and then added to white oil containing 2wt%CS2 and sulfided at 7.0MPa hydrogen pressure for 12h.

[0095] Example 3: Preparation of rare earth supported catalysts for trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in basic Examples 2-3 was calcined in air at 2°C / min to 490°C for 4 hours, and then added to white oil containing 2wt% CS2 and sulfided under 8.0MPa hydrogen pressure for 12 hours.

[0096] Example 4: Preparation of rare earth supported catalysts for trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in basic examples 2-4 was calcined in air at 2°C / min to 480°C for 4 hours, and then added to white oil containing 2wt% CS2 and sulfided at 6.0MPa hydrogen pressure for 12 hours.

[0097] Example 5: Preparation of rare earth supported catalysts for trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in Basic Examples 2-5 was calcined in air at 2°C / min to 480°C for 4 hours, and then added to white oil containing 2 wt% CS2 and sulfided under 6.0 MPa hydrogen pressure for 12 hours.

[0098] Example 6: Preparation of rare earth supported catalysts for trifluoromethanesulfonic acid The preparation method is as follows: The solid precursor powder prepared in Basic Examples 2-6 was calcined in air at 2°C / min to 480°C for 4 hours, and then added to white oil containing 2wt% CS2 and sulfided at 6.0MPa hydrogen pressure for 12 hours.

[0099] Comparative Example 1 The components are as follows, calculated as a percentage by weight: γ-Al₂O₃ 78.1%; CeO2 0.75%; CoO 3.7%; and MoO3 13.4%.

[0100] Preparation method: (1) A rare earth element impregnation solution of a certain concentration was prepared with deionized water, and then the rare earth element impregnation solution was impregnated onto γ-Al2O3 by equal volume impregnation method. A certain amount of ammonia water was added during the impregnation process to improve the dispersion of the impregnation solution. After impregnation, the solution was aged at room temperature for about 12 hours, dried at 120℃ for about 8 hours, and calcined at 540℃ for about 4 hours to obtain a composite carrier. (2) Take an appropriate amount of water, turn on the stirrer and heat to 40°C, add citric acid CA (CA / Co = 1.5) and stir until completely dissolved, then add cobalt carbonate and stir until no bubbles are generated. Slowly heat the solution to boiling point until all the materials are dissolved (no bubbles are generated), stop heating, cool to room temperature and stir, add ammonia water to 85% of the final volume, then slowly add ammonium heptamolybdate and stir until completely dissolved, add ammonia water to the final volume to obtain the active metal impregnation solution, seal and store for later use; (3) The active metal impregnation solution obtained in step (2) is loaded onto the composite carrier obtained in step (1) by the equal volume impregnation method. After saturation, it is stirred for 10 min, aged at room temperature for 12 h, dried at 100℃ for 8 h, and calcined at 540℃ for 4 h to obtain the catalyst.

[0101] Comparative Example 2 The difference from Example 2 is that the solid precursor powder is different; specifically, the solid precursor powder prepared based on Comparative Example 2-1 is different, while the remaining steps are the same as in Example 2.

[0102] Comparative Example 3 The difference from Example 2 is that the solid precursor powder is different; specifically, the solid precursor powder prepared based on Comparative Example 2-2 is used. The remaining steps are the same as in Example 2. Comparative Example 4 The difference from Example 2 is that the solid precursor powder is different; specifically, the solid precursor powder prepared based on Comparative Examples 2-3 is different. The remaining steps are the same as in Example 2.

[0103] Comparative Example 5 The difference from Example 6 is that the solid precursor powder is different; specifically, the solid precursor powder prepared based on Comparative Examples 2-4 is different. The remaining steps are the same as in Example 6.

[0104] Comparative Example 6 The difference from Example 6 is that the solid precursor powder is different; specifically, the solid precursor powder prepared based on Comparative Examples 2-5 is different. The remaining steps are the same as in Example 6.

[0105] Detection Example 1 1. Experimental Methods (1) Microreactor test of diesel hydrorefining (raw material S=3231ppm, N=688ppm): The catalysts prepared in Examples 1-3 and Comparative Examples 1-4 were used in the microreactor test of diesel hydrorefining.

[0106] Diesel hydrorefining microreactor test: (1.1) Device and bed loading A fixed-bed microreactor was used for evaluation. The reaction tube (column) was approximately 50 cm long, and the catalyst bed was positioned near the thermocouple temperature measurement location to ensure consistent bed temperature monitoring and control. The catalyst loading section was located approximately 20 cm below the upper opening of the reaction tube, with an external electric heater providing an effective heating length of approximately 30 cm; the catalyst bed height was approximately 10 cm. Quartz sand with a particle size of approximately 0.5-5 mm was used for dispersion and uniform distribution within the bed to improve fluid distribution, reduce channeling risk, and stabilize bed pressure drop. The catalyst particles were prepared by cutting and then loaded (approximately 1-5 mm): the main bed particles were approximately 1.5 cm long; a transition layer of approximately 1 cm thick, consisting of smaller particles (approximately 0.25-10 mm), was placed on the top layer to reduce inlet bypass and localized flow deviation. This structure was used to obtain stable and repeatable hydrorefining evaluation data under fixed-bed microreactor conditions.

[0107] (1.2) System replacement and boosting leak detection After loading, the system is first purged with nitrogen (or hydrogen) to remove air; then, the pressure is gradually increased and maintained at low temperature for leak testing. Once no leaks are confirmed, the heating process begins. This step is to prevent residual oxygen from causing abnormal exothermic reactions during the oxidation of the catalyst's active phase or the sulfidation stage.

[0108] (1.3) In-situ sulfidation activation of catalyst For Ni-Mo supported hydrorefining catalysts, in-situ sulfidation is typically performed before testing to convert the active phase to a sulfidized state. The sulfidation system described in the appendix can be used: white oil containing 2 wt% CS2 is used as the sulfidation oil, and sulfidation is carried out for 12 hours under hydrogen pressure conditions; the hydrogen sulfidation pressure can be selected in the range of 6.0-8.0 MPa (e.g., 6.0, 7.0, or 8.0 MPa) according to the corresponding catalyst example. After sulfidation, hydrogen is maintained for atmosphere protection, and the feedstock is switched to diesel fuel while maintaining stable pressure and flow rate to avoid bed oxidation.

[0109] (1.4) Reaction condition setting and continuous operation The reaction temperature was stabilized at 360℃, and the liquid hourly space velocity (LHSV) was set to 1.5 h⁻¹. -1 The system was operated continuously for 100 hours; the sulfur and nitrogen contents of the diesel feedstock were 3231 ppm and 688 ppm, respectively. An activation and fluctuation phase is permissible during the initial operation period, but the system typically enters a relatively stable reaction range after approximately 60 hours.

[0110] (1.5) Sampling and product separation After cooling and condensation, the reaction products enter the gas-liquid separation unit. The gas phase is either discharged or metered, while the liquid phase is sampled periodically. It is recommended to cover the entire process and focus on collecting samples from the stable phase (e.g., 60-100h) to use the average value of the stable phase for cross-sectional comparisons of different catalysts.

[0111] (1.6) Analysis and evaluation indicators The sulfur content, nitrogen content, and product color (or appearance) of the diesel liquid phase products were tested, and the desulfurization conversion rate and denitrification conversion rate were calculated based on the influent and effluent contents. The sulfur, nitrogen, and color of the stable operation section were used as the core evaluation results. The test data are shown in Table 2 below.

[0112] (2) Heavy VGO hydrogenation purification test: The catalysts prepared in Examples 4-6, Comparative Examples 1-2 and Comparative Examples 5-6 were used in the heavy VGO hydrogenation purification test.

[0113] Heavy VGO hydrogenation purification test: (2.1) Filling and bed structure The unit remains a fixed-bed reactor, with bed structure, temperature measurement locations, and dispersion methods consistent with the diesel microreactor (same reaction tube, same heater coverage area, same bed height, and same quartz sand dispersion method) to ensure comparability in evaluation between different feedstock systems. An upper transition layer (small particle zone) is also included in the bed to improve inlet fluid distribution and reduce the risk of flow deviation and localized coking under heavy feedstocks.

[0114] (2.2) In-situ sulfidation activation In-situ sulfidation was performed using white oil containing 2wt% CS2 under hydrogen pressure for 12 hours; the sulfidation pressure could be in the range of 6.0-8.0 MPa as described in the example. After sulfidation, hydrogen protection was maintained, and the feed was gradually switched to heavy VGO feedstock and kept stable.

[0115] (2.3) Reaction conditions and operation The evaluation was conducted within the temperature range of 370-415℃, with a liquid hourly space velocity (LHSV) set to 1.0 h⁻¹. -1 The system was run continuously for 100 hours. The activation and stabilization processes were recorded, and data from the stabilization period after approximately 60 hours were used for comparison.

[0116] (2.4) Post-sampling processing and analysis After cooling and separation, the product was sampled as a liquid phase. Due to the high viscosity of VGO and its tendency to separate into layers or precipitate wax, the sample should be thoroughly mixed at an appropriate temperature before being dispensed to ensure the representativeness of sulfur and nitrogen analysis. The main analytical items were sulfur content, nitrogen content, and product color, and the conversion rate was calculated. The test data are shown in Table 3 below.

[0117] 2. Experimental Results Each catalyst undergoes a certain activation and stabilization process in the initial stage of the reaction, and gradually enters the stable reaction stage after about 60 hours of operation.

[0118] The results in Table 1 show that, within the stable operating range, the catalysts prepared using the method of this invention exhibit significantly better desulfurization and denitrification performance than the comparative examples. Specifically, the sulfur content of the diesel products from Examples 1-3 consistently decreased to the range of 10-15 ppm, corresponding to sulfur conversion rates exceeding 99.5%; simultaneously, the nitrogen content in the diesel products remained consistently at 7-9 ppm, corresponding to nitrogen conversion rates exceeding 98.6%. Throughout the stable operating period, the products from each example remained colorless and transparent, without significant darkening or deterioration, indicating that the catalysts possess good selectivity and stability.

[0119] In contrast, the comparative catalyst exhibited significantly insufficient desulfurization and denitrification capabilities under the same reaction conditions. Its diesel product retained a sulfur content of 85-120 ppm and a nitrogen content of 48-68 ppm, corresponding to significantly lower sulfur and nitrogen conversion rates than the example catalyst. Furthermore, the product color ranged from light yellow to yellow. These results demonstrate that introducing trifluoromethanesulfonic acid rare earth complexes and constructing a rare earth-Ni-Mo composite precursor system can significantly improve the catalyst's deep desulfurization and denitrification capabilities and operational stability during diesel hydrorefining.

[0120] Table 2. Test results of diesel hydrorefining microreactor

[0121] During the test, each catalyst exhibited certain fluctuations in the early stage of operation, and gradually reached a relatively stable reaction state after about 60 hours of operation.

[0122] Table 3 below shows the test results of heavy VGO hydrorefining. It indicates that, under stable operating conditions, the catalysts prepared in Examples 4-6 all exhibited good adaptability to heavy feedstocks. The sulfur content of their VGO products was stably distributed between approximately 2200-2500 ppm, corresponding to a sulfur conversion rate of 59.0-64.5%; simultaneously, the nitrogen content of the products was stable at 300-340 ppm, corresponding to a nitrogen conversion rate of 50.6-56.4%. The products obtained in each example were all light yellow in color, with no obvious abnormal deepening observed, indicating that the catalysts could maintain relatively stable reaction behavior when processing feedstocks with high aromatic hydrocarbon and high impurity content.

[0123] In contrast, the comparative catalysts showed significantly weaker hydrorefining effects under the same operating conditions. Their VGO products generally had sulfur content exceeding 3000 ppm, with some comparative examples even exceeding 4000 ppm. Nitrogen content remained within the range of 420-610 ppm, with overall low sulfur and nitrogen conversion rates, and the product was yellow in color. These results further demonstrate that the trifluoromethanesulfonic acid rare earth supported catalyst prepared in this invention can effectively mitigate the competitive adsorption effects of polycyclic aromatic hydrocarbons and nitrogen-containing compounds during heavy distillate oil processing, thereby improving the overall efficiency and stability of the hydrorefining reaction.

[0124] Table 3. Test results of hydrogenation refining of heavy VGO

[0125] Verification of technical effectiveness and / or analysis of technical problem solving To address the common problems of existing Ni-Mo hydrorefining catalysts in the processing of diesel and heavy distillate oils, such as the reaction rate being easily affected by PAH competitive adsorption, rapid activity decay in the initial operation stage, and obvious tendency for carbon deposition and deactivation, this invention introduces trifluoromethanesulfonic acid rare earth complexes into the traditional Ni–Mo / γ-Al2O3 system to construct a rare earth composite precursor, which is then calcined and sulfided to form a NiMoS active system. The above-mentioned technical problems have been systematically verified and analyzed.

[0126] In the microreactor test of diesel hydrorefining, the catalyst in the example rapidly entered the stable reaction range within approximately 60 hours after a brief activation phase at the beginning of operation, and maintained low sulfur and nitrogen residue levels during subsequent continuous operation. Compared with the comparative example, the catalyst in the example showed significantly higher sulfur and nitrogen conversion rates during the stable operation phase, and the product color remained stable without significant darkening. This indicates that the introduction of trifluoromethanesulfonic acid rare earth complexes can effectively regulate the formation behavior of the NiMoS active phase during metal sulfidation, making it easier to generate and maintain stable edge sulfidation sites. This alleviates the competition for active sites by aromatics and nitrogen-containing compounds, solving the problem of large fluctuations in desulfurization and denitrification efficiency in the initial stage of traditional catalysts.

[0127] Under heavy VGO hydrorefining conditions, the catalyst is more prone to competitive adsorption and carbon deposition deactivation due to the high aromatic content and complex molecular structure of the feedstock. Test results show that the catalyst in the example can maintain relatively stable sulfur and nitrogen conversion levels under high temperature and high load conditions, with significantly lower sulfur and nitrogen contents than the comparative catalyst, and smaller overall fluctuations. In contrast, the comparative catalyst exhibited lower sulfur and nitrogen conversion rates and unstable product quality within the same operating time. These results further verify the enhancing effect of trifluoromethanesulfonic acid rare earth complexes on the stability and deactivation resistance of the metal sulfide phase in heavy feedstock systems.

[0128] Rare earth trifluoromethanesulfonic acid complexes can form stable and dispersed composite systems with Ni and Mo precursors in the solution stage of the metal complex system, and synergistically participate in the structural evolution of the NiMoS active phase during subsequent calcination and sulfidation. On the one hand, the electronic regulation effect of rare earth elements helps to improve the electronic distribution state of metal sulfides, promotes the dissociation and activation of hydrogen molecules at active edge sites, and on the other hand, the regulation effect of rare earth elements on the acidity of the support surface can suppress side reactions and carbon deposition caused by excessively acidic centers, thereby reducing catalyst deactivation in the early stage of the reaction.

[0129] This invention introduces rare earth trifluoromethanesulfonic acid complexes into the Ni-Mo hydrorefining catalytic system and adjusts the ratio of the catalyst support to the rare earth trifluoromethanesulfonic acid complexes. Without changing the traditional process flow, it effectively solves the technical problems in the prior art, such as the hydrorefining reaction being easily affected by PAH competitive adsorption, insufficient initial stability, and obvious tendency to carbon deposition and deactivation. This makes the catalyst exhibit better reaction stability, desulfurization and denitrification efficiency, and engineering applicability in the processing of diesel and heavy distillate oils.

[0130] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a rare earth-supported catalyst for trifluoromethanesulfonic acid, characterized in that, The rare earth trifluoromethanesulfonic acid complex was directly introduced into the Ni-Mo system to obtain a metal complex solution. The catalyst support was then modified with the metal complex and then subjected to depressurization and drying to obtain a solid precursor powder, thus successfully loading the rare earth-Ni-Mo composite precursor onto the catalyst support. Finally, the solid precursor powder was calcined and sulfided to prepare the rare earth trifluoromethanesulfonic acid supported catalyst. The rare earth trifluoromethanesulfonate complexes are selected from lanthanum trifluoromethanesulfonate, cerium trifluoromethanesulfonate, lutetium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, or samarium trifluoromethanesulfonate. The mass ratio of the trifluoromethanesulfonic acid rare earth complex to the catalyst support is 1-3:25-50.

2. The preparation method according to claim 1, characterized in that, The rare earth trifluoromethanesulfonic acid complex is lanthanum trifluoromethanesulfonic acid or cerium trifluoromethanesulfonic acid.

3. The preparation method according to claim 1, characterized in that, The mass ratio of the trifluoromethanesulfonic acid rare earth complex to the catalyst support is 1-3:

50.

4. The preparation method according to claim 1, characterized in that, The method for preparing the metal complex system solution includes the following steps: (1.1) Weigh out the rare earth trifluoromethanesulfonic acid complex and add it to ethanol. Stir and dissolve to obtain solution 1; (1.2) Weigh out ammonium heptamolybdate and nickel nitrate hexahydrate, dissolve them in water, and then add citric acid to obtain solution 2; (1.3) Mix and stir solution 1 and solution 2 to form a metal complex system solution.

5. The preparation method according to claim 4, characterized in that, The mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is 1.5-2.5:0.8-1.

5.

6. The preparation method according to claim 4, characterized in that, The mass ratio of ammonium heptamolybdate and nickel nitrate hexahydrate in step (1.2) is 1.8-2.4:0.9-1.

2.

7. The preparation method according to claim 1, characterized in that, The method for preparing the solid precursor powder includes the following steps: (2.1) After drying the catalyst support, store it under nitrogen protection for later use; (2.2) Immerse the metal complex system solution prepared in step (1.3) into the catalyst support prepared in step (2.1), let it stand, and obtain material 1; (2.3) Reduce the pressure and dry the material 1 to obtain solid precursor powder.

8. The preparation method according to claim 7, characterized in that, The settling time mentioned in step (2.2) is 30-60 minutes.

9. The preparation method according to claim 7, characterized in that, The decompression temperature described in step (2.3) is 50-70℃.

10. The preparation method according to claim 7, characterized in that, The drying process described in step (2.3) consists of a first drying and a second drying.

11. The preparation method according to claim 10, characterized in that, The temperature for the first drying step is 80-90℃, and the drying time is 10-12 hours.

12. The preparation method according to claim 10, characterized in that, The second drying process takes place at a temperature of 110-120℃ for 4-5 hours.

13. The preparation method according to claim 12, characterized in that, The second drying process takes place in a vacuum environment.

14. The preparation method according to claim 1, characterized in that, The roasting temperature is 480-500℃.

15. The preparation method according to claim 1, characterized in that, The hydrogen partial pressure of the sulfidation is 6-8 MPa.

16. A rare earth-supported trifluoromethanesulfonic acid catalyst prepared by the preparation method according to any one of claims 1-15.

17. The application of the trifluoromethanesulfonic acid rare earth supported catalyst of claim 16 in diesel fuel processing.

18. The application according to claim 17, characterized in that, The diesel processing involves one or more of the following: reducing the sulfur / nitrogen content of diesel, increasing the cetane number, improving combustion performance, and hydrogenating polycyclic aromatic hydrocarbons to saturate.

19. The application of the trifluoromethanesulfonic acid rare earth supported catalyst of claim 16 in the processing of heavy distillate oils.

20. The application according to claim 19, characterized in that, The heavy distillate oil processing involves one or more of the following: reducing the sulfur / nitrogen content of diesel oil, increasing the cetane number, improving combustion performance, and hydrogenating polycyclic aromatic hydrocarbons to saturate.

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