Solid acid catalysts and their preparation and use

Abstract

A solid acid catalyst, its preparation, and its use are disclosed. The catalyst comprises (a) a metal oxide support; and (b) at least one modified metal component. When trimethylphosphine was used as a probe molecule for characterization based on solid-state nuclear magnetic resonance techniques, the catalyst exhibited a spectral peak in the range of -5 ppm to -20 ppm. The catalyst can be used in non-aromatic hydrocarbon cracking reactions, and has the advantages of high conversion and few side reactions.

Description

Detailed Description of the Invention

[0001] [Technical Field] This application relates to the field of acid catalysts, and in particular to solid acid catalysts, their preparation and use.

[0002] [Background technology] Lewis acids are chemical species with vacant orbitals that can accept electrons. For example, metal ion sites on metal oxide surfaces with unsaturated coordination are potential Lewis acid sites. The Lewis acid sites on silica-alumina molecular sieves are closely related to Al, and the vacant Al sites can participate in reactions as Lewis acid sites on the molecular sieves. Lewis acids are widely used in various catalytic fields. During the reaction process, Lewis acids not only catalyze reactions independently but also cooperate with other active sites, such as Brønsted acid sites, metal species, and alkaline sites, to obtain the desired product. The formation of C-C bonds catalyzed by Lewis acids is an important method for C-C bond construction in classical organic synthesis. The Friedel-Crafts reaction (FC) and the Diels-Alder reaction (DA) can be carried out using the most common Lewis acid catalysts, such as AlCl3 and TiCl4. Lewis acid-base catalyst pairs, consisting of a Lewis acid and a Lewis base, can catalyze the reaction of small molecules to produce polymers, attracting attention in fields such as polymer synthesis. In addition to thermal catalysis, Lewis acids are also widely used in electrocatalysis and photocatalysis. For example, hindered Lewis acid-base pairs can promote highly selective electrocatalytic urea production processes, and Lewis acid sites and photosensitive centers can work together to achieve efficient photooxidation reactions. Research on Lewis acid sites has attracted increasing attention. The strength of the Lewis acid reflects the ability of the active site to accept electrons during the reaction and is closely related to the molecular diffusion and reaction process on the catalyst surface. Therefore, adjusting the strength of the Lewis acid on the catalyst surface is an important way to control the catalytic reaction performance.

[0003] CN108,262,057A discloses a catalyst system consisting of a molecular sieve, a metal adjuvant and a binder, which can improve the cracking activity of the catalyst by adjusting the acid distribution in the catalyst, thereby improving the conversion and selectivity of non-aromatic hydrocarbons.

[0004] Patent No. CN105,272,804A discloses a method for increasing xylene production by transalkylation of aromatic hydrocarbons and cracking of non-aromatic hydrocarbons. This method uses a beta molecular sieve as the main active component and a dual-layer catalyst system. By selectively cracking non-aromatic hydrocarbons to produce C2-C5 light components, a higher yield of xylenes and a higher purity of benzene product can be achieved.

[0005] CN 108,948,366A discloses the preparation of an Fe-MOF catalyst with abundant Lewis acid sites and its use in desulfurization. The catalyst is prepared from iron salt and trimesic acid as raw materials to form an Fe-MOF catalyst with abundant Lewis acid sites.

[0006] CN112,473,743A discloses a Lewis acid-base bifunctional catalyst, its preparation method, and use. The catalyst is a three-dimensional porous structure catalyst formed by assembling a mixed ligand and a central particle, where the mixed ligand is composed of 2,4,6-tris(4-pyridyl)-1,3,5-triazine and trimesic acid, and Ni(II) is used as the central particle. The catalyst has a bifunctional active site of Lewis acid-base pair and can be used for one-pot cascade aromatic alcohol catalytic oxidation Knoevenagel condensation reaction under mild conditions.

[0007] CN 1,362,286A discloses an alkylation catalyst having an inorganic or organic porous support and a heteropolyacid and a Lewis acid as main components, in which the heteropolyacid and the Lewis acid are simultaneously supported on a porous support, with the heteropolyacid accounting for 10 wt% to 55 wt% of the support and the Lewis acid accounting for 1 wt% to 5 wt% of the support.

[0008] In summary, the current focus on the effect of Lewis acids on catalyst performance is mainly on increasing the amount of acid and its interaction with other active sites, and the hydrocracking catalysts for non-aromatic hydrocarbons known in the prior art still suffer from the problem of insufficient conversion of non-aromatic hydrocarbons.

[0009] [Contents of the invention] An object of the present application is to provide a solid acid catalyst which has the advantages of high conversion and few side reactions when used in the hydrocracking reaction of non-aromatic hydrocarbons, as well as its preparation and use.

[0010] In order to achieve the above object, in one aspect, the present application provides a solid acid catalyst, (a) Metal oxide support; (b) at least one modifying metal component, wherein the metal in said modifying metal component is selected from the group consisting of Group VB, Group VIB, Group VIII, Group IVA, or Group VA metals, or combinations thereof; The catalyst exhibits a spectral peak in the range of -5 ppm to -20 ppm when characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule.

[0011] In another aspect, (1) a step of etching a metal oxide support raw material with an acidic pH buffer solution having a pH value of 1 to 5 to obtain a support precursor; (2) washing the carrier precursor obtained in step (1) until the pH of the washing solution reaches 6 to 7, and then drying the carrier to obtain a carrier; and (3) A method for preparing the catalyst of the present application is provided, which includes the steps of supporting the modifying metal component on the support obtained in step (2), optionally drying the support, and calcining the support under an inert or reducing atmosphere to obtain a catalyst.

[0012] In another aspect, there is provided the use of the present catalyst in the hydrocracking of non-aromatic hydrocarbons.

[0013] In yet another aspect, a method for hydrocracking non-aromatic hydrocarbons is provided, the method comprising contacting a feedstock comprising non-aromatic hydrocarbons with a catalyst in the presence of hydrogen to carry out a hydrocracking reaction.

[0014] The catalyst of the present application has super-strong Lewis acid sites on its surface. When the catalyst is used in the hydrocracking of non-aromatic hydrocarbons, the presence of the acid sites, combined with the strong Lewis acid sites and metal sites on the catalyst surface, promotes stable hydrocracking of non-aromatic hydrocarbons, thereby improving the reaction conversion and reducing side reactions. At the same time, the catalyst preparation method of the present application is simple, economically feasible, and easy to industrialize.

[0015] Other features and advantages of the present application are described in detail in the following specific embodiment section.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are used to provide a further understanding of the present application and constitute a part of this specification. The drawings are used to explain the present invention together with the following specific embodiments, but are not intended to limit the present invention. In the accompanying drawings, FIG. 1 shows the catalysts obtained in Example 1 and Comparative Examples 1 and 2. 31 1 is a P MAS NMR spectrum of the catalyst obtained in Example 1. FIG. 2 is a P MAS NMR spectrum of the catalyst obtained in Example 1. FIG. 3 is a P MAS NMR spectrum of the catalyst obtained in Example 1. FIG. 4 is a P MAS NMR spectrum of the catalyst obtained in Example 1.

[0017] [Specific Embodiments] Specific embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for the purposes of illustration and explanation of the present application, and are not intended to limit the present application.

[0018] Any specific numerical value disclosed herein (including the endpoints of a numerical range) should be understood to be neither limited to the exact value of that numerical value nor to include values ​​close to that exact value, such as all possible values ​​within a range of ±5% of the exact value. Furthermore, the disclosed numerical ranges can be arbitrarily combined between the endpoints of the ranges, between the endpoints and any particular point within the range, and between any individual particular point within the range, to obtain one or more new numerical ranges, and these new numerical ranges should also be considered to be specifically disclosed herein.

[0019] Unless otherwise specified, terms used herein have the same meaning as commonly understood by those skilled in the art. If a term has a definition herein and that definition differs from the meaning commonly understood in the art, the definition herein shall prevail.

[0020] As is known in the art, when a solid acid is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, a catalyst having Bronsted acid sites on its surface exhibits a spectral peak in the range of 0 ppm to −5 ppm (i.e., the peak value of the spectral peak is in the range of 0 ppm to −5 ppm). On the other hand, catalysts with Lewis acid sites exhibit spectral peaks in the range of -5 ppm to -60 ppm, and the closer the spectral peak is to the low magnetic field of -5 ppm, the stronger the acidity of the corresponding Lewis acid site (see references: Progress in development and application of solid-state NMR for solid acid catalysis, ZHENG Anmin et. al., Chinese Journal of Catalysis, 2013, vol. 34, No.3, 436-491; Surface acidity of tin dioxide nanomaterials revealed with 31P solid-state NMR spectroscopy and DFT calculation, RSC Advance, 2021, 11, 25004-25009;31 P NMR chemical shifts of phosphorus probes as reliable and practical acidity scales for solid and liquid catalysts, Chemical Reviews, 2017, 117, 12475-12531).

[0021] In the present application, the amount of strong Lewis acid and the total amount of Lewis acid in the catalyst are measured by a pyridine adsorption infrared method, and are expressed as a peak at 1450 cm in the infrared spectrum after desorption at 200 °C. -1 The peak area of ​​the absorption peak located near 1450 cm in the infrared spectrum after pyridine elimination at 400 °C -1 The ratio of the peak area of ​​the adjacent absorption peaks is recorded as the ratio of the amount of strong Lewis acid to the amount of total Lewis acid.

[0022] As used herein, the term "non-aromatic hydrocarbon" has the meaning commonly understood in the art and generally refers to hydrocarbon compounds that do not contain aromatic rings in their molecular structure, such as cycloalkanes, acyclic alkanes, etc., which may be saturated or unsaturated.

[0023] As used herein, the term "cycloalkane" has the meaning commonly understood in the art and generally refers to a saturated hydrocarbon compound having one or more carbon rings in its molecular structure, such as cyclohexane, methylcyclopentane, etc.

[0024] In this application, except for the contents explicitly described, any undescribed matters or items are directly adopted from those known in the art, and no changes are required. Furthermore, any embodiment described in this specification can be freely combined with one or more other embodiments described in this specification, and the technical solutions or technical ideas formed thereby are all considered to be part of the original disclosure or original description of this specification, and should not be considered as new content not disclosed or anticipated in this specification unless a person skilled in the art considers the combination to be obviously unreasonable.

[0025] All patent and non-patent literature, including but not limited to textbooks, journal articles, and the like, referred to herein is hereby incorporated by reference in its entirety.

[0026] As described above, in a first aspect, the present application provides a solid acid catalyst, comprising: (a) Metal oxide support; (b) at least one modifying metal component; When the catalyst is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, the catalyst exhibits a spectral peak in the range of −5 ppm to −20 ppm, i.e., the catalyst exhibits at least one spectral peak having a peak value in the range of −5 ppm to −20 ppm.

[0027] Existing catalysts for hydrocracking of non-aromatic hydrocarbons typically use a Brønsted acid and a metal component for synergistic catalytic reactions. However, these catalyst systems often suffer from problems such as low conversion and incomplete hydrocracking. The present catalyst exhibits a peak in the range of -5 ppm to -20 ppm in solid-state nuclear magnetic resonance spectra obtained using trimethylphosphine as a probe molecule, indicating the presence of superstrong Lewis acid sites on the catalyst surface. Without being limited to a particular theory, the present inventors have discovered that these types of superstrong Lewis acid sites can activate C-H and C-C bonds through their strong interaction with hydrocarbon reactants in the hydrocracking reaction, thereby promoting the heterogeneous cleavage of these chemical bonds. In the hydrocracking of non-aromatic hydrocarbons, carbenium ion formation and β-cleavage are two important reaction processes, related to the heterogeneous cleavage of C-H and C-C bonds, respectively. The superstrong Lewis acid sites in the present catalyst system not only promote these processes but also exhibit good synergistic effects with the metal component on the catalyst surface. Therefore, the super-strong Lewis acid sites of the catalyst of the present application have the effect of promoting the formation of carbenium ions and facilitating the occurrence of the β-cleavage process in the hydrocracking of non-aromatic hydrocarbons. The synergistic effect of the strong Lewis acid sites on the catalyst surface and the metal promotes the stable progress of the hydrocracking of non-aromatic hydrocarbons, thereby improving the conversion rate of the hydrocracking of non-aromatic hydrocarbons and reducing undesirable side reactions.

[0028] The catalyst of the present application has coordinatively unsaturated metal ion sites uniformly distributed on the support surface, and the introduced modifying metal can bond to these coordinatively unsaturated sites to form uniformly distributed superstrong Lewis acid sites, thereby exhibiting the above-mentioned specific characteristics of the solid-state nuclear magnetic resonance spectrum. Without being limited to a particular theory, it is believed that the superstrong Lewis acid sites of the catalyst of the present application can be represented by the structure shown in the following formula: [ka] In the formula, M1 is a metal element in the metal oxide support, and the number of O atoms coordinating with it depends on the specific metal oxide selected; the number of coordinating oxygen atoms shown in the above formula is merely representative; here, M1 is a strong Lewis acid site; M2 is a modifying metal, and the number of O atoms coordinating with M2 also depends on the specific metal selected; the number of coordinating oxygen atoms shown in the above formula is merely representative; the brackets [ ] in the above formula indicate that M1 is a coordinatively unsaturated metal ion site.

[0029] In certain preferred embodiments, when the catalyst is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, the sum of the peak areas of the catalyst in the range of −5 ppm to −20 ppm is 1% to 100%, for example, 1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 75%, 80%, 85%, 80%, 85%, 90%, 95 ... 0%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99%, 100%, or any value within a range formed by any two of these values, preferably 20% to 100%, for example, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99%, or 100%. The above ratios represent the ratio of the amount of superstrong Lewis acid to the total amount of Lewis acid in the catalyst of the present application.

[0030] In certain specific embodiments, when the catalyst of the present application is characterized by electron paramagnetic resonance, the catalyst exhibits a spectral peak in the range of g=1.9 to 2.1, i.e., the catalyst exhibits at least one spectral peak having a peak value in the range of g=1.9 to 2.1, indicating the presence of defect sites formed by coordinatively unsaturated sites on the surface of the catalyst.

[0031] In a preferred embodiment, when the catalyst is subjected to a pyridine adsorption infrared test using pyridine as a probe molecule, the ratio of the amount of strong Lewis acid to the total amount of Lewis acid in the catalyst is 5% to 100%, for example, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100%, preferably 20% to 100%, and more preferably 40% to 100%.

[0032] According to the present application, the metal oxide support is required to be capable of generating surface coordinatively unsaturated metal ion sites after being treated in an acidic environment having a pH value of 1 to 5. In a preferred embodiment, the metal oxide support is selected from the group consisting of Al2O3, TiO2, ZrO2, ZnO, Nb2O5, CuO, CeO2, or a combination thereof, more preferably selected from the group consisting of ZrO2, Nb2O5, or a combination thereof.

[0033] According to the present application, the metal in the modifying metal component can be selected from the group consisting of metals of Group VB, Group VIB, Group VIII, Group IVA or Group VA, or combinations thereof. In a preferred embodiment, the metal in the modifying metal component is selected from the group consisting of V, Cr, Mo, W, Co, Sn, Bi, or combinations thereof, more preferably Co, W, or combinations thereof.

[0034] In a preferred embodiment, based on the weight of the catalyst, the content of the modifying metal component, calculated as metal, is 0.1% to 50%, for example, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, or 40%, preferably 0.5% to 40%, more preferably 1% to 10%, and the content of the metal oxide support, calculated as metal oxide, is 50% to 99.9%, for example, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%, preferably 60% to 99.5%, more preferably 90% to 99%.

[0035] In a specific embodiment, the metal oxide support is treated by etching using an acidic pH buffer solution, and the pH value of the acidic pH buffer solution is preferably 1 to 5, for example, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0 or 4.5, more preferably 2 to 4.

[0036] In a specific embodiment, a catalyst is treated in a reducing or inert atmosphere, and when the catalyst is characterized by electron paramagnetic resonance, the total peak area at g=1.9-2.1 of the catalyst increases by 5% to 100%, e.g., 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or 95%, compared to a catalyst that has not been treated in a reducing or inert atmosphere.

[0037] In a second aspect, there is provided a method for preparing the catalyst of the present application, the method comprising: (1) a step of etching a metal oxide support raw material with an acidic pH buffer solution having a pH value of 1 to 5, preferably 2 to 4, to obtain a support precursor; (2) washing the carrier precursor obtained in step (1) until the pH of the washing solution reaches 6 to 7, and then drying the carrier to obtain a carrier; and (3) A step of supporting the modifier metal component on the support obtained in step (2), optionally drying the support, and calcining the support in an inert or reducing atmosphere to obtain a catalyst.

[0038] In a specific embodiment, the catalyst preparation method of the present application does not include a step of calcining the support precursor obtained in step (1) or the support obtained in step (2) prior to step (3).

[0039] In the catalyst preparation method described herein, the surface of the metal oxide support is etched with an acidic buffer solution within a specific pH range, and the modifying metal component is thoroughly washed and loaded. The resulting solution is then calcined under an inert or reducing atmosphere, thereby uniformly introducing super-strong Lewis acid sites onto the support surface. Without being limited to a particular theory, the inventors have discovered through research that during the metal loading process, metal precursors tend to bond to the coordinatively unsaturated sites on the support surface. Acidic pH buffer solutions with a pH between 1 and 5 can reliably etch the support in a suitable and stable acidic environment, thereby gently etching only the surface and near-surface atomic layers (e.g., 1 to 3 atomic layers from the surface) of the support metal oxide. This results in the formation of coordinatively unsaturated metal ion sites uniformly distributed on the support surface without simultaneously reconstructing the surface of the support metal oxide. After thoroughly washing and loading the modifying metal component, the use of an inert or reducing atmosphere can further stabilize the coordinatively unsaturated sites on the support surface during the calcination process, thereby facilitating the immobilization of the metal component onto the support. When the supported metal binds to these coordinatively unsaturated sites, uniformly distributed superstrong Lewis acid sites are formed, and excessive aggregation of the Lewis acid sites does not occur, resulting in a catalyst having the superstrong Lewis acid sites of the present invention.

[0040] The specific chemical composition of the acidic pH buffer solution used in this application is not strictly limited, as long as it can maintain the desired pH value (i.e., a pH value of 1 to 5, e.g., 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, or 4.5, preferably 2 to 4) during the etching procedure in step (1). Specific examples of buffer solutions include, but are not limited to, citric acid-sodium citrate buffer, acetic acid-sodium acetate buffer, glycine-hydrochloric acid buffer, citric acid-sodium hydroxide-hydrochloric acid buffer, etc. In a preferred embodiment, the acidic pH buffer solution used in step (1) is acetic acid-sodium acetate buffer. Using an acidic buffer solution within the above pH range not only enables the etching process of the surface and near-surface atomic layers of the support to be realized, introducing coordinatively unsaturated metal ion sites, but also prevents the reconstruction of the atomic layers on the support surface during the harsh etching process. This allows the coordinatively unsaturated metal ion sites generated by etching to be uniformly distributed on the surface of the support, facilitating the subsequent introduction of the modifier metal and the generation of superstrong Lewis acid sites.

[0041] In a specific embodiment, during the etching treatment in step (1), the pH value of the acidic pH buffer solution is maintained within a range of 1 to 5, for example, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, or 4.5, preferably 2 to 4. If the pH value of the acidic pH buffer solution exceeds this range, the superstrong Lewis acid sites required in the present application cannot be formed. Specifically, when the pH is greater than 5, it is difficult to achieve the etching process of the support surface. When the pH is less than 1, the etching process is too severe, causing reconstruction of the support surface and the loss of most of the structure. As a result, coordinatively unsaturated metal ion sites cannot be uniformly introduced onto the support surface, and the superstrong Lewis acid sites cannot be formed after the modifier metal is loaded.

[0042] According to the present application, the support material used in step (1) can be selected from various metal oxides that can generate surface coordinatively unsaturated metal ion sites after etching treatment in an acidic environment having a pH value of 1 to 5. In a preferred embodiment, the support material is selected from the group consisting of Al2O3, TiO2, ZrO2, ZnO, Nb2O5, CuO, CeO2, or a combination thereof, more preferably selected from the group consisting of ZrO2, Nb2O5, or a combination thereof.

[0043] In a preferred embodiment, the mass ratio of the carrier raw material to the acidic pH buffer solution in step (1) is 1:5 to 1:50, for example, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45 or 1:50, more preferably 1:10 to 1:20.

[0044] In a preferred embodiment, the etching conditions in step (1) include an etching temperature of 10°C to 50°C, e.g., 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, or 50°C, preferably 15°C to 30°C, and an etching time of 1 to 20 hours, e.g., 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 12 hours, 15 hours, 18 hours, or 20 hours, preferably 3 to 10 hours. During the etching treatment, the support raw material is preferably mixed with an acidic pH buffer solution before etching. The etching treatment in step (1) of the present application is performed under relatively mild conditions, thereby enabling a uniform increase in the number of coordinatively unsaturated sites on the support surface. In contrast, etching under violent reaction conditions (e.g., boiling or near-boiling conditions) or for too long a time tends to destroy the surface structure of the metal oxide and cause the coordinatively unsaturated metal ion sites to disappear, which is unfavorable for the formation of coordinatively unsaturated metal ion sites uniformly distributed on the support surface.

[0045] In a preferred embodiment, in step (1), the reaction mixture is filtered after etching is completed to obtain the support precursor.

[0046] According to the present invention, in step (2), the support precursor obtained in step (1) is washed until the pH value of the washing solution reaches 6 to 7. Generally, washing can be performed with water, but other conventional washing agents, such as ethanol or a mixture of ethanol and water, can also be used. In step (2) of the present invention, washing the support precursor to approximately neutral pH completely removes the residue of the acidic pH buffer, thereby preventing the poisoning of the acidic sites on the catalyst surface by the residue. In contrast, if the support precursor is directly dried and then subjected to subsequent treatment without washing, the coordinatively unsaturated metal ion sites on the support surface are covered, making it difficult for the modifying metal to adhere to the coordinatively unsaturated metal ion sites. This results in a rapid decrease in the catalyst acid density and makes it impossible to generate superstrong Lewis acid sites.

[0047] In a preferred embodiment, the drying conditions in step (2) include a drying temperature of 50°C to 130°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, or 130°C, preferably 80°C to 120°C, and a drying time of 5 to 30 hours, for example, 5 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, 22 hours, 25 hours, 28 hours, or 30 hours, preferably 12 to 20 hours.

[0048] In a specific embodiment, when the support obtained in step (2) is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, the support exhibits a spectral peak in the range of −5 ppm to −60 ppm, indicating that a coordinatively unsaturated moiety having Lewis acidity is formed on the surface of the obtained support precursor.

[0049] According to the present invention, there is no step of calcining the support precursor obtained in step (1) or the support obtained in step (2) before step (3). If the support precursor or the support is calcined before step (3), the coordinatively unsaturated metal ion sites generated during the etching process will disappear due to surface reconstruction at high temperatures during calcination. As a result, when the modifying metal is supported, the modifying metal cannot be selectively fixed at the coordinatively unsaturated metal ion sites, and the catalyst will not be able to generate superstrong Lewis acid sites.

[0050] According to the present application, in step (3), the modifying metal component can be supported on the support obtained in step (2) by various conventional methods, for example, the supporting method can be impregnation, precipitation or physical kneading, preferably incipient wetness impregnation.

[0051] According to the present application, the metal in the modifying metal component used in step (3) can be selected from the group consisting of metals of Group VB, Group VIB, Group VIII, Group IVA or Group VA, or a combination thereof. In a preferred embodiment, the metal in the modifying metal component is selected from the group consisting of V, Cr, Mo, W, Co, Sn, Bi, or a combination thereof, more preferably Co, W, or a combination thereof.

[0052] In a preferred embodiment, the modifying metal components are supported on the support in the form of metal precursors, which are preferably salts of the corresponding metals. For example, the precursor of V can be vanadate, the precursor of Cr can be chromium nitrate or chromium chloride, the precursor of Mo can be molybdate, the precursor of W can be tungstate, the precursor of Co can be cobalt nitrate or cobalt chloride, the precursor of Ni can be nickel nitrate or nickel chloride, the precursor of Sn can be tin chloride, and the precursor of Bi can be bismuth nitrate, preferably cobalt nitrate and ammonium tungstate.

[0053] In a preferred embodiment, in step (3), the drying conditions include a drying temperature of 50°C to 130°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, or 130°C, preferably 80°C to 120°C, and a drying time of 5 to 30 hours, for example, 5 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, 22 hours, 25 hours, 28 hours, or 30 hours, preferably 12 to 20 hours.

[0054] According to the present invention, in step (3), the support loaded with the modifying metal component is calcined under a reducing or inert atmosphere to stabilize the coordinatively unsaturated sites on the support surface during the calcination process, thereby promoting the immobilization of the metal component to the support. In contrast, calcination under a non-reducing or non-inert atmosphere (e.g., air) leads to reconstruction of the support surface, resulting in the loss of coordinatively unsaturated metal ion sites and the inability to form strong Lewis acid sites. When the catalyst was characterized by electron paramagnetic resonance, the total peak area in the g range of 1.9 to 2.1 for the catalyst obtained by calcination under a reducing or inert atmosphere increased by at least 5% compared to the catalyst obtained by calcination under a non-reducing or non-inert atmosphere, indicating that the surface of the catalyst of the present invention has more defect sites formed by coordinatively unsaturated sites.

[0055] In a preferred embodiment, in step (3), the firing conditions include a firing temperature of 250°C to 600°C, for example, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, or 600°C, preferably 300°C to 500°C, and a firing time of 1 to 5 hours, for example, 1.0 hour, 1.5 hours, 2.0 hours, 2.5 hours, 3.0 hours, 3.5 hours, 4.0 hours, 4.5 hours, or 5.0 hours, preferably 2 to 4 hours.

[0056] In a preferred embodiment, in step (3), the firing atmosphere is selected from the group consisting of H2, N2, Ar, He, a H2 / Ar mixed gas, a H2 / N2 mixed gas, a H2 / He mixed gas, or a combination thereof.

[0057] According to the present application, the morphology of the support in the catalyst does not change significantly before and after etching, calcination, and loading. In some embodiments, the specific surface area of ​​the catalyst is slightly larger, for example, 0.5% to 5% larger, than the specific surface area of ​​the original support.

[0058] In a third aspect, there is provided the use of the present catalyst in the hydrocracking of non-aromatic hydrocarbons.

[0059] In a fourth aspect, a method for hydrocracking non-aromatic hydrocarbons is provided, the method comprising contacting a feedstock comprising non-aromatic hydrocarbons with a catalyst of the present application in the presence of hydrogen to carry out a hydrocracking reaction.

[0060] In a preferred embodiment, the conditions for the hydrocracking reaction are a reaction temperature of 200°C to 500°C, a reaction pressure of 0.5 MPa to 6 MPa, a hydrogen / hydrocarbon molar ratio of 2 to 10, and a raw material weight hourly space velocity of 1.0 h -1 ~20.0h -1 This includes being.

[0061] The catalyst of the present application is applicable to the hydrocracking reaction of various non-aromatic hydrocarbons, and there is no strict limitation in the present application. In a preferred embodiment, the non-aromatic hydrocarbon is selected from the group consisting of cycloalkanes containing 6 to 9 carbon atoms, acyclic alkanes, or combinations thereof. More preferably, the non-aromatic hydrocarbon is selected from the group consisting of cyclohexane, methylcyclopentane, or combinations thereof.

[0062] In a specific embodiment, the target product of the hydrocracking reaction of non-aromatic hydrocarbons is C2-C5 light non-aromatic hydrocarbons.

[0063] [Example] The present invention will be described in more detail below through examples, but the present invention is not limited thereto.

[0064] (Test Method) In the following examples and comparative examples, solid-state nuclear magnetic resonance spectroscopy ( 31 The P MAS NMR (P MAS NMR) test method is as follows: after activating the sample under vacuum, a certain amount of trimethylphosphine molecules is adsorbed in situ onto the sample to be tested, the sample is loaded into a N2-protected glove box, and the test is performed using a Bruker AVANCE III 400WB solid-state nuclear magnetic resonance spectrometer with a rotor diameter of 4 mm and a sample rotation speed of 12 kHz. 31 P MAS NMR spectra are examined by high-power proton decoupling, and the results are calibrated and analyzed using NH4H2PO4 as a standard.

[0065] In the following examples and comparative examples, electron paramagnetic resonance (EPR) tests were carried out using an EMX-8 / 2.7 instrument manufactured by Bruker, Germany. Samples were tested at room temperature with a frequency of 9.88 GHz and a microwave power of 2.0 mW, and spectra were obtained after standardization according to the magnetic field conditions, scanning conditions, etc. during the test.

[0066] In the following examples and comparative examples, the pyridine adsorption infrared test method using pyridine as a probe molecule is as follows: The acid value and acid amount of the sample are measured using a Nexus™ infrared spectrometer (Py-IR) manufactured by Nicolet, USA. During the test, the sample is compressed into a tablet and 10 -4 The sample was evacuated to 100 Pa, heated to 400 °C, and heat-treated for 2 hours. After the temperature was lowered to 200 °C, pyridine was statically adsorbed for 1 minute, and after equilibration for 5 minutes, low vacuum was applied for 10 minutes and high vacuum for 30 minutes, and an IR scan was performed. The temperature was then raised to 400 °C within 10 minutes, after which the sample was equilibrated for 5 minutes, and an IR scan was performed. The Bronsted acidity and Lewis acidity were 1540 cm−1, respectively. -1 and around 1450cm -1 It is calculated from the absorption peak area around 1450 cm in the infrared spectrum after desorption at 200 °C. -1The peak area of ​​the absorption peak located near 1450 cm in the infrared spectrum after pyridine elimination at 400 °C -1 The ratio of the peak area of ​​the adjacent absorption peaks is recorded as the ratio of the amount of strong Lewis acid to the total amount of Lewis acid.

[0067] In the following examples and comparative examples, the specific surface area of ​​the samples was measured using a Tristar II 3020 fully automated specific surface area and pore size analyzer manufactured by Micromeritics, Inc. After pretreatment, the samples were placed in liquid nitrogen, and the nitrogen adsorption and desorption isotherms were measured at -196°C. The specific surface area of ​​the samples was then calculated using the BET equation.

[0068] Example 1 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A1 with a Co content of 5 wt%. 31The results of P MAS NMR characterization are shown in Figure 1. A spectral peak was observed at -14 (±1) ppm, which was a signal generated by trimethylphosphine molecules adsorbed on the superstrong Lewis acid sites on the catalyst surface. The sum of the peak areas of the catalyst in the range of -5 ppm to -20 ppm accounted for 40% of the sum of the peak areas of the catalyst in the range of -5 ppm to -60 ppm. Catalyst A1 was subjected to an adsorption infrared spectroscopy test using pyridine as the probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A1 was 82%. The results of EPR characterization of catalyst A1 are shown in Figure 2. The sample exhibited a spectral peak at g = 2.002, indicating that the catalyst had defect sites formed by coordinatively unsaturated sites. The total peak area of ​​catalyst A1 in the range of g = 1.9 to 2.1 ppm increased by approximately 92% compared to the catalyst calcined in a non-reducing or non-inert atmosphere (Comparative Example 2).

[0069] (Catalytic reaction performance test) 10 g of catalyst A1 was placed in a reactor, and hydrogen was introduced and reduced at 380 °C for 3 hours. After the temperature was lowered to 350 °C, hydrogen and a mixture of 50 wt% cyclohexane and 50 wt% methylcyclopentane were introduced and the reaction was carried out under the reaction conditions of a total weight space velocity of 5 h -1 The reaction temperature was 350°C, the reaction pressure was 5 MPa, and the hydrogen / hydrocarbon molar ratio was 3. The test results are shown in Table 1.

[0070] [Example 2] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 3 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A2 with a Co content of 5 wt%. 31The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A2 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A2 was 56%. The EPR characterization results of catalyst A2 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 83% compared to the catalyst of Comparative Example 2.

[0071] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0072] [Example 3] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A3 with a Co content of 2 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A3 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A3 was 42%. The EPR characterization results of catalyst A3 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 95% compared to the catalyst of Comparative Example 2.

[0073] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0074] [Example 4] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of ammonium tungstate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A4 with a W content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A4 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A4 was 79%. The EPR characterization results of catalyst A4 were similar to those in Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 90% compared to the catalyst in Comparative Example 2.

[0075] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0076] [Example 5] 10 g of Nb2O5 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A5 with a Co content of 5 wt%. 31The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A5 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A5 was 75%. The EPR characterization results of catalyst A5 were similar to those in Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 89% compared to the catalyst calcined in a non-reducing or non-inert atmosphere.

[0077] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0078] [Example 6] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 1 hour, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A6 with a Co content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A6 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A6 was 17%. The EPR characterization results of catalyst A6 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 21% compared to the catalyst of Comparative Example 2.

[0079] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0080] [Example 7] 10 g of ZrO2 was taken and etched in a citric acid-sodium citrate buffer solution with a pH of 4.8. The mass ratio of the support to the citric acid-sodium citrate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A7 with a Co content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm, which was a signal generated by trimethylphosphine molecules adsorbed on strong Lewis acid sites on the catalyst surface. Catalyst A7 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the strong Lewis acid content to the total Lewis acid content in Catalyst A7 was 12%. The EPR characterization results for Catalyst A7 were similar to those in Example 1, with the total peak area in the g range of 1.9 to 2.1 increasing by approximately 15% compared to the catalyst in Comparative Example 2, which was not treated in a reducing or inert atmosphere.

[0081] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0082] [Example 8] 10 g of ZnO was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A8 with a Co content of 5 wt%. 31The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A8 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A8 was 15%. The EPR characterization results of catalyst A8 were similar to those in Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 19% compared to the catalyst calcined in a non-reducing or non-inert atmosphere.

[0083] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0084] [Example 9] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of chromium nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A9 with a Cr content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A9 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A9 was 9%. The EPR characterization results of catalyst A9 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 80% compared to the catalyst of Comparative Example 2.

[0085] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0086] [Example 10] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A10 with a Co content of 0.5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A10 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A10 was 36%. The EPR characterization results of catalyst A10 were similar to those in Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 98% compared to the catalyst in Comparative Example 2.

[0087] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0088] [Example 11] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an H2 atmosphere to obtain catalyst A11 with a Co content of 5 wt%. 31The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A11 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A11 was 80%. The EPR characterization results of catalyst A11 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 96% compared to the catalyst of Comparative Example 2.

[0089] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0090] [Example 12] 10 g of ZrO2 was taken and etched in a citric acid-sodium hydroxide-hydrochloric acid buffer solution with a pH of 4.3. The mass ratio of the support to citric acid-sodium hydroxide-hydrochloric acid was 1:15. After etching at 18°C ​​for 3 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A12 with a Co content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A12 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A12 was 13%. The EPR characterization results of catalyst A12 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 17% compared to the catalyst of Comparative Example 2.

[0091] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0092] [Example 13] 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 28°C for 5 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst A13 with a Co content of 5 wt%. 31 The P MAS NMR spectrum showed a spectral peak at -14 (±1) ppm. Catalyst A13 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst A13 was 78%. The EPR characterization results of catalyst A13 were similar to those of Example 1, and the total peak area in the g range of 1.9 to 2.1 was increased by approximately 86% compared to the catalyst of Comparative Example 2.

[0093] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0094] [Comparative Example 1] 10 g of ZrO2 was taken, and a certain amount of cobalt nitrate was impregnated into the incipient wetness, and then dried at 100 °C for 15 hours. The obtained product was calcined at 400 °C for 3 hours under an Ar atmosphere to obtain catalyst DA1 with a Co content of 5 wt%. 31 No spectral peaks were observed in the P MAS NMR spectrum in the range of -5 ppm to -20 ppm. The sum of the peak areas in the range of -5 ppm to -20 ppm was 0% of the sum of the peak areas in the range of -5 ppm to -60 ppm. Catalyst DA1 was subjected to an adsorption infrared spectrum test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA1 was 2%.

[0095] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0096] Comparative Example 2 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the carrier raw material to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the carrier precursor was obtained by suction filtration. This carrier precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a carrier. The obtained carrier was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined in an air atmosphere at 400°C for 3 hours to obtain catalyst DA2 with a Co content of 5 wt%. 31 In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Furthermore, the sum of the peak areas in the range of -5 ppm to -20 ppm was 0% of the sum of the peak areas in the range of -5 ppm to -60 ppm. Catalyst DA2 was subjected to an adsorption infrared spectroscopy test using pyridine as the probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA2 was 3%. The EPR characterization results for catalyst DA2 are shown in Figure 2. No clear signal peaks of oxygen defects were observed in the g range of 1.9 to 2.1.

[0097] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0098] Comparative Example 3 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution of pH 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst DA3 with a Co content of 5 wt%. 31In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Catalyst DA3 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA3 was 1%.

[0099] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0100] Comparative Example 4 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After treatment at 90°C for 30 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst DA4 with a Co content of 5 wt%. 31 In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Catalyst DA4 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA4 was 2%.

[0101] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0102] Comparative Example 5 10 g of WO3 was taken and calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst DA5.

[0103] Catalyst DA5 31In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Catalyst DA5 was subjected to an adsorption infrared spectrum test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA5 was 40%.

[0104] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0105] Comparative Example 6 10 g of ZrO2 was taken and etched with a hydrochloric acid solution of pH 0.1. The mass ratio of the support to the hydrochloric acid solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, and then dried at 100°C for 15 hours to obtain a support. The obtained support was incipiently impregnated with a certain amount of cobalt nitrate and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst DA6 with a Co content of 5 wt%. 31 In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Catalyst DA6 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA6 was 0.5%.

[0106] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0107] Comparative Example 7 10 g of ZrO2 was taken and etched in an acetic acid-sodium acetate buffer solution with a pH of 3.8. The mass ratio of the support to the acetic acid-sodium acetate buffer solution was 1:15. After etching at 18°C ​​for 8 hours, the support precursor was obtained by suction filtration. This support precursor was washed with deionized water until the pH of the washing solution reached 7, dried at 100°C for 15 hours, and calcined at 400°C for 3 hours to obtain a support. The obtained support was impregnated with a certain amount of cobalt nitrate as an incipient wetness and dried at 100°C for 15 hours. The obtained product was calcined at 400°C for 3 hours under an Ar atmosphere to obtain catalyst DA7 with a Co content of 5 wt%. 31 In the P MAS NMR spectrum, no spectral peaks were observed in the range of -5 ppm to -20 ppm. Catalyst DA7 was subjected to an adsorption infrared spectroscopy test using pyridine as a probe molecule. The ratio of the amount of strong Lewis acid to the total amount of Lewis acid in catalyst DA7 was 2%.

[0108] The reaction performance test of this catalyst was carried out with reference to Example 1. The test results are shown in Table 1.

[0109] [Table 1-1] [Table 1-2] [Table 1-3] [Table 1-4]

[0110] As shown in the test results in Table 1, the catalysts of Examples 1 to 13 can significantly improve the conversion of the raw materials cyclohexane and methylcyclopentane and the yield of the target C2 to C5 products compared to the catalysts of Comparative Examples 1 to 7.

[0111] Although the preferred embodiments of the present application have been described in detail above, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, and all of these simple modifications fall within the protection scope of the present application.

[0112] Furthermore, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner unless there is a contradiction, and in order to avoid unnecessary repetition, the various possible combinations will not be described individually in this application.

[0113] Furthermore, the embodiments of the present application can be combined in any manner, and as long as they do not deviate from the concept of the present application, they should also be considered to be part of the invention of the present application. [Brief explanation of the drawings]

[0114] [Figure 1] 3 shows 31P MAS NMR spectra of the catalysts obtained in Example 1 and Comparative Examples 1 and 2. [Figure 2] 1 shows EPR spectra of the catalysts obtained in Example 1 and Comparative Example 2.

Claims

1. A solid acid catalyst, (a) a metal oxide support, preferably Al ２ O ３ , TiO ２ , ZrO ２ , ZnO, Nb ２ O ５ , CuO, CeO ２ or a combination thereof; (b) at least one modifying metal component, wherein the metal in said modifying metal component is selected from the group consisting of Group VB, Group VIB, Group VIII, Group IVA or Group VA metals, or combinations thereof, and preferably selected from the group consisting of V, Cr, Mo, W, Co, Sn, Bi, or combinations thereof; A catalyst wherein when the catalyst is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, the catalyst exhibits a spectral peak in the range of -5 ppm to -20 ppm.

2. The catalyst according to claim 1, wherein, when the catalyst is subjected to a pyridine adsorption infrared test using pyridine as a probe molecule, the ratio of the amount of strong Lewis acid to the amount of total Lewis acid in the catalyst is 5% to 100%, preferably 20% to 100%, and more preferably 40% to 100%.

3. The metal oxide support is ZrO ２ , Nb ２ O ５ or a combination thereof; and / or the metal in said modifying metal component is selected from the group consisting of Co, W or a combination thereof.

4. Catalyst according to any one of the preceding claims, wherein the content of the modifying metal component, calculated as metal, is 0.1% to 50%, preferably 0.5% to 40%, more preferably 1% to 10%, and the content of the metal oxide support, calculated as metal oxide, is 50% to 99.9%, preferably 60% to 99.5%, more preferably 90% to 99%, based on the weight of the catalyst.

5. When the catalyst is characterized by solid-state nuclear magnetic resonance using trimethylphosphine as a probe molecule, the sum of the peak areas of the catalyst in the range of −5 ppm to −20 ppm accounts for 1% to 100%, preferably 20% to 100%, of the sum of the peak areas of the catalyst in the range of −5 ppm to −60 ppm; and / or Catalyst according to any one of the preceding claims, wherein when the catalyst is characterized by electron paramagnetic resonance, the catalyst exhibits a spectral peak in the range of g = 1.9 to 2.

1.

6. (1) Etching a metal oxide support raw material with an acidic pH buffer solution having a pH value of 1 to 5, preferably 2 to 4, to obtain a support precursor; (2) washing the carrier precursor obtained in step (1) until the pH of the washing solution reaches 6 to 7, and then drying the carrier to obtain a carrier; and (3) A method for preparing the catalyst according to any one of the preceding claims, comprising the steps of: (i) loading the modifier metal component onto the support obtained in step (2), optionally drying the support, and calcining the support under an inert or reducing atmosphere to obtain a catalyst.

7. The method according to claim 6, wherein the step (3) is not preceded by a step of calcining the support precursor obtained in step (1) or the support obtained in step (2).

8. 8. The method according to claim 6 or 7, wherein the acidic pH buffer solution used in step (1) is selected from the group consisting of citric acid-sodium citrate buffer solution, acetic acid-sodium acetate buffer solution, glycine-hydrochloric acid buffer solution, and citric acid-sodium hydroxide-hydrochloric acid buffer solution, and is preferably acetic acid-sodium acetate buffer solution.

9. The carrier raw material used in step (1) is Al ２ O ３ , TiO ２ , ZrO ２ , ZnO, Nb ２ O ５ , CuO, CeO ２ or a combination thereof, preferably ZrO ２ , Nb ２ O ５ or a combination thereof; The method according to any one of claims 6 to 8, wherein in step (1), the mass ratio of the carrier raw material to the acidic pH buffer solution is 1:5 to 1:50, preferably 1:10 to 1:

20.

10. 10. The method according to claim 6, wherein in step (1), the etching conditions include an etching temperature of 10°C to 50°C, preferably 15°C to 30°C, and an etching time of 1 to 20 hours, preferably 3 to 10 hours.

11. The method according to any one of claims 6 to 10, wherein in step (2), the drying conditions include a drying temperature of 50°C to 130°C, preferably 80°C to 120°C, and a drying time of 5 to 30 hours, preferably 12 to 20 hours.

12. In step (3), the drying conditions include a drying temperature of 50°C to 130°C, preferably 80°C to 120°C, and a drying time of 5 to 30 hours, preferably 12 to 20 hours; and / or The firing conditions are that the firing temperature is 250°C to 600°C, preferably 300°C to 500°C, and the firing time is 1 to 5 hours, preferably 2 to 4 hours; and the firing atmosphere is H ２ , N ２ , Ar, He, H ２ / Ar mixed gas, H ２ / N ２ Mixed gas, H ２ 12. The method of claim 6, wherein the gas is selected from the group consisting of a gas mixture of H₂O, ...

13. Use of the catalyst according to any one of claims 1 to 5 in the hydrocracking reaction of non-aromatic hydrocarbons.

14. A method for hydrocracking non-aromatic hydrocarbons, comprising a step of contacting a feedstock containing non-aromatic hydrocarbons with the catalyst according to any one of claims 1 to 5 in the presence of hydrogen to carry out a hydrocracking reaction.

15. The conditions for the hydrocracking reaction are a reaction temperature of 200°C to 500°C, a reaction pressure of 0.5 MPa to 6 MPa, a hydrogen / hydrocarbon molar ratio of 2 to 10, and a raw material weight hourly space velocity of 1.0 h －１ ~20.0h －１ 15. The use according to claim 13 or the method according to claim 14, comprising:

16. 15. The use according to claim 13 or the method according to claim 14, wherein the non-aromatic hydrocarbon is selected from the group consisting of cycloalkanes containing 6 to 9 carbon atoms, acyclic alkanes, or combinations thereof, preferably the non-aromatic hydrocarbon is selected from the group consisting of cyclohexane, methylcyclopentane, or combinations thereof.

Images