Transalkylation catalyst, preparation method and application thereof, and aromatic hydrocarbon liquid phase transalkylation method

Abstract

The invention relates to the technical field of catalysts, and discloses a transalkylation catalyst, a preparation method and application thereof, and an aromatic hydrocarbon liquid-phase transalkylation method. The catalyst comprises Y zeolite, clinoptilolite, copper oxide and a binder. The transalkylation catalyst is applied to liquid-phase transalkylation reaction of aromatic hydrocarbon, is beneficial to promoting transalkylation reaction of materials containing toluene and C9 < + > aromatic hydrocarbon, achieves the purpose of increasing the yield of xylene, has high aromatic hydrocarbon reaction activity and high xylene selectivity, and is suitable for industrial production of xylene.

Description

Technical Field

[0001] This invention relates to the technical field of catalysts, specifically to an alkyl transfer catalyst, its preparation method and application, and a method for liquid-phase alkyl transfer of aromatics. Background Technology

[0002] Xylene, as an important organic chemical raw material, has a wide range of industrial applications. It can be used as a solvent in industries such as coatings, resins, dyes, and inks; as a synthetic monomer or solvent in industries such as pharmaceuticals, explosives, and pesticides; and as a component of high-octane gasoline. The most widely used xylene product is para-xylene, which is used to produce polyesters, and its demand is increasing daily. The main industrial methods for producing xylene include: 1) using naphtha as raw material through a series of processes such as catalytic reforming, separation, and purification to obtain xylene and other high-value-added products; 2) utilizing toluene disproportionation and alkyl transfer processes, i.e., the conversion of toluene and C9 aromatics into benzene and xylene under the action of a catalyst. This reaction mainly includes: toluene disproportionation reaction and alkyl transfer reaction. Toluene disproportionation reaction generally refers to the reaction of two toluene molecules to produce one benzene molecule and one xylene molecule. Alkyl transfer reaction generally refers to the reaction of one toluene molecule and one trimethylbenzene molecule under the action of a catalyst to produce two xylene molecules.

[0003] Conventional toluene disproportionation and alkyl transfer processes are typically carried out at relatively high reaction temperatures (350-410℃). Materials are mixed in the gas phase and contact the catalyst for conversion. The reaction usually consumes a large amount of hydrogen. The products are separated into the target products benzene and xylene. Unreacted useful materials are separated and recycled. Excessive cracking often occurs during the reaction, resulting in the loss of aromatics, and a small amount of heavy aromatic byproducts are also generated. These byproducts cannot be converted and must be discharged, all of which increase energy consumption and production costs. Therefore, higher demands are placed on refining and chemical enterprises to achieve energy conservation, emission reduction, and improved efficiency.

[0004] Patent application CN109790084A discloses a method for alkyl transfer of heavy aromatic hydrocarbons. In the presence of 0 wt% or more hydrogen, alkyl transfer of C9... + The first feedstock of aromatics contacts the catalyst in an effective vapor phase under dealkylation conditions, allowing some C9 hydrocarbons to be processed. + Aromatic hydrocarbons undergo dealkylation to produce compounds containing benzene, toluene, and residual C9 hydrocarbons. + The first product of aromatic hydrocarbons. Containing C9... + A second feed of aromatics and benzene and / or toluene in an effective liquid phase C9 + Contact with a second catalyst under alkyl transfer conditions allows at least some C9 atoms to be transferred. + Aromatic hydrocarbons undergo alkyl transfer to generate a second product containing xylene. This patent can reduce C9... +Costs of aromatics conversion, elimination or reduction of aromatics from gasification and recycling, reduction of hydrogen use, and reduction of the size of dealkylation reactors.

[0005] Patent application CN109803944A discloses a method for the disproportionation and alkyl transfer of heavy aromatics. Under effective gas-phase toluene disproportionation conditions, a toluene-containing feedstock is contacted with a first catalyst to generate a first product comprising benzene, unreacted toluene, and a significant amount of p-xylene; under effective C9... + Under alkyl transfer conditions, with a hydrogen / hydrocarbon molar ratio of 0-10 and a hydrogen content of 0 wt% or higher, C9 hydrocarbons are incorporated. + Aromatic hydrocarbons and benzene feedstocks are contacted with a second catalyst to achieve C9 synthesis. + Alkyl transfer of aromatics yields a second product containing xylene. This patent improves the yield and production efficiency of para-xylene by supplying fresh toluene to the disproportionation zone. The alkyl transfer reaction is carried out in the liquid phase, which extends catalyst lifetime, improves aromatic selectivity, and reduces energy consumption under less harsh conditions.

[0006] Patent application CN108779047A discloses a liquid-phase aromatic alkyl transfer method, employing catalysts including molecular sieves with a 3D or 1D 12-membered ring framework structure, acidic microporous materials with a pore size of at least 6.0 Å, and / or molecular sieves with an MWW framework structure. In this method, at least a portion of the feed is in the liquid phase, making it suitable for naphthalene-containing feed streams. The liquid-phase alkyl transfer reaction in this patent is carried out at lower severity, which can extend catalyst lifetime, improve the selectivity of aromatic compounds with the desired carbon number (such as C8 aromatic compounds), and has advantages such as lower reaction temperature, reduced energy consumption, and reduced by-product formation.

[0007] Liquid-phase aromatic alkyl transfer technology involves mixing reactants in a liquid phase and contacting them with a catalyst for conversion. The reaction temperature is typically between 200-330℃. It offers advantages such as low energy consumption, minimal aromatic loss, fewer byproducts, and high xylene selectivity. While hydrogen is required in the reaction, the amount used is significantly lower than in gas-phase reactions; hydrogen simply needs to be dissolved in the reactants. This technology aims to achieve a greener, lower-carbon, and more efficient xylene production process by optimizing catalyst formulations and adjusting reaction parameters. Specifically, this technology will focus on developing highly active and selective catalysts suitable for liquid-phase reactions to reduce reaction temperature and hydrogen consumption. Simultaneously, by precisely controlling reaction conditions, it will reduce aromatic loss and byproduct formation, thereby improving the overall efficiency of the production process.

[0008] Currently, problems such as low conversion efficiency of aromatics and poor selectivity of xylene under liquid phase conditions are still prevalent. Therefore, the development of efficient, low-energy-consumption, high-conversion-rate, and high-selectivity liquid-phase aromatic alkyl transfer technology is of great significance. Summary of the Invention

[0009] The purpose of this invention is to address the problems of low aromatic hydrocarbon conversion and low xylene selectivity in the liquid-phase alkyl transfer reaction of aromatic hydrocarbons in existing technologies. This invention provides an alkyl transfer catalyst, its preparation method, its application, and a method for liquid-phase alkyl transfer of aromatic hydrocarbons. This alkyl transfer catalyst features high aromatic hydrocarbon conversion and high xylene selectivity, and can promote the liquid-phase alkyl transfer reaction of aromatic hydrocarbons.

[0010] To achieve the above objectives, a first aspect of the present invention provides an alkyl transfer catalyst, wherein the catalyst comprises γ-zeolite, clinoptilolite, copper oxide, and a binder.

[0011] Preferably, the average grain size of the Y zeolite is less than 500 nm, and more preferably 100-300 nm.

[0012] Preferably, the average grain size of the clinoptilolite is less than 300 nm, and more preferably 50-150 nm.

[0013] A second aspect of the present invention provides a method for preparing the alkyl transfer catalyst described in the first aspect above, the method comprising the following steps:

[0014] (1) In the presence of a solvent, Y zeolite, clinoptilolite, Cu precursor, binder, and optionally extrusion aid and adhesive solvent are mixed.

[0015] (2) The mixture obtained in step (1) is shaped, and then dried and roasted.

[0016] The third aspect of this invention provides the application of the alkyl transfer catalyst described above in the liquid-phase alkyl transfer reaction of aromatics; the alkyl transfer catalyst is the alkyl transfer catalyst described in the first aspect or the alkyl transfer catalyst prepared by the preparation method described in the second aspect.

[0017] A fourth aspect of the present invention provides a method for liquid-phase alkyl transfer of aromatic hydrocarbons, the method comprising: in the presence of hydrogen, under liquid-phase reaction conditions, reacting a mixture containing toluene and C9... + A mixture of aromatics is reacted with an alkyl transfer catalyst; the alkyl transfer catalyst is the alkyl transfer catalyst described in the first aspect or the alkyl transfer catalyst prepared by the preparation method described in the second aspect.

[0018] Preferably, the liquid phase reaction conditions include a temperature of 200-350℃, more preferably 250-300℃.

[0019] The alkylation catalyst provided by this invention, through the above technical solution, comprises γ-zeolite, clinoptilolite, copper oxide, and a binder. The zeolite contains numerous acidic active sites that can donate protons, thereby promoting various acid-catalyzed reactions, including the disproportionation of aromatics and alkyl transfer reactions. The combined use of clinoptilolite and γ-zeolite enhances catalytic activity and selectivity, improves the selectivity of xylene and the conversion rate of aromatics, and achieves more efficient catalytic effects and economic benefits. Detailed Implementation

[0020] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0021] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0022] In this invention, "xylene" refers to the product in which two hydrogen atoms on the benzene ring are replaced by methyl groups, and there are three isomers: ortho, meta, and para. The xylene described in this invention can be one or more of the above three isomers or a mixture thereof.

[0023] The first aspect of the present invention provides an alkyl transfer catalyst comprising γ-zeolite, clinoptilolite, copper oxide, and a binder.

[0024] Liquid-phase aromatic alkyl transfer technology involves mixing reactants in a liquid phase and contacting them with a catalyst for conversion. The aim is to achieve a greener, lower-carbon, and more efficient xylene production process by optimizing catalyst formulations and adjusting reaction parameters. Through continuous research, the inventors of this invention have discovered that the synergistic effect of γ-zeolite, clinoptilolite, and copper oxide can significantly improve the alkyl transfer activity of the catalyst and enhance the conversion rate of aromatics and the selectivity of xylene in the liquid-phase aromatic alkylation transfer reaction.

[0025] According to the present invention, preferably, based on the total amount of catalyst, the weight percentage of Y zeolite is 50-79%, more preferably 60-70%; the weight percentage of clinoptilolite is 10-20%, more preferably 12-18%; the weight percentage of copper oxide is 1-5%, more preferably 2-4%; and the weight percentage of binder is 10-25%, more preferably 10-20%, more preferably 15-20%.

[0026] In the catalyst of the present invention, this preferred method is more conducive to improving the activity and selectivity of the catalyst, so as to achieve better results in aromatic conversion and xylene selectivity, and improve the overall efficiency and economy of alkyl transfer reaction.

[0027] In this invention, the copper oxide content can be obtained through elemental analysis. The contents of the Y zeolite, clinoptilolite, and binder can be calculated based on the amount of materials fed.

[0028] The present invention does not particularly limit the type of adhesive, and any conventional choice in the art can be used. Preferably, the adhesive is silicon dioxide and / or aluminum oxide.

[0029] According to the present invention, preferably, the SiO2 / Al2O3 molar ratio of the Y zeolite is 8-20, more preferably 8-15, and even more preferably 10-15.

[0030] According to the present invention, preferably, the SiO2 / Al2O3 molar ratio of the clinoptilolite is 5-20, more preferably 8-16, and more preferably 12-15.

[0031] The preferred approach adopted in this invention is more advantageous in providing appropriate acidity and pore structure in the catalyst, ensuring high activity and selectivity in the alkyl transfer reaction, while avoiding catalyst activity degradation or performance instability caused by excessively high or low acidity. The selection of these parameters allows the catalyst to achieve better performance in terms of reaction activity and selectivity.

[0032] In this invention, inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the silicon-to-aluminum molar ratio (SiO2 / Al2O3) of the molecular sieve. The testing instrument was a Varian 725-ES series ICP-AES instrument.

[0033] According to the present invention, preferably, the average grain size of the Y zeolite is less than 500 nm, more preferably 100-300 nm, and more preferably 200-250 nm.

[0034] According to the present invention, preferably, the average grain size of the clinoptilolite is less than 300 nm, more preferably 50-150 nm, and more preferably 75-100 nm.

[0035] Using this size of crystal grain can balance the catalytic activity and selectivity, and reduce the formation of byproducts.

[0036] In this invention, the molecular sieve particle size analysis was obtained by observation using an XL30E scanning electron microscope from Philips, Netherlands.

[0037] In particular, the alkyl transfer catalyst provided by this invention significantly improves the activity of the alkyl transfer reaction, the conversion rate of aromatics, and the selectivity of xylene through the synergistic effect of γ-zeolite, clinoptilolite, and copper oxide, thereby achieving a greener and lower-carbon production process. The optimized component ratio demonstrates significant advantages in improving reaction selectivity and catalytic efficiency.

[0038] A second aspect of the present invention provides a method for preparing the alkyl transfer catalyst described in the first aspect above, the method comprising the following steps:

[0039] (1) In the presence of a solvent, Y zeolite, clinoptilolite, Cu precursor, binder, and optionally extrusion aid and adhesive solvent are mixed.

[0040] (2) The mixture obtained in step (1) is shaped, and then dried and roasted.

[0041] It should be noted that the adhesive mentioned in step (1) of the present invention is an adhesive in a broad sense. It can be an adhesive, an adhesive precursor, or a mixture of an adhesive and an adhesive precursor. The present invention does not have any particular limitation on this.

[0042] In this invention, the binder precursor refers to a substance that can be converted into the binder through a subsequent calcination step. Those skilled in the art, knowing the types of binders, know which binder precursor to choose.

[0043] The present invention does not have any particular limitation on the source of the Y zeolite and clinoptilolite, which can be obtained from commercial purchases or prepared using conventional methods in the art.

[0044] The present invention does not have any special requirements for the mixing method, as long as it is conducive to sufficient contact of the substances in step (1). Those skilled in the art can choose according to actual needs.

[0045] This invention does not particularly limit the type or amount of the solvent, as long as it can provide the necessary environment for mixing. It can be added alone or mixed with other raw materials before addition. According to one specific embodiment of the invention, the solvent can be water.

[0046] The present invention does not have any particular requirements for the molding method, and those skilled in the art can choose according to actual needs, such as kneading molding, extrusion molding, etc.

[0047] According to a preferred embodiment of the present invention, the Cu precursor is at least one of copper nitrate, copper chloride, and copper oxide, and the Cu precursor can be obtained from commercially available sources or prepared using methods known in the art.

[0048] Cu precursors may also contain water of crystallization.

[0049] According to the present invention, preferably, the range of types of extrusion aids is wide, and can be various extrusion aids conventionally used in the art, such as at least one selected from guar gum powder, methylcellulose, hydroxypropyl methylcellulose and dextrin.

[0050] According to the present invention, preferably, the amount of the extrusion aid is 1-5% of the total weight of Y zeolite, clinoptilolite and binder on a dry basis, preferably 1-3%.

[0051] According to the present invention, preferably, the range of types of adhesive solvents is relatively wide, and can be various adhesive solvents conventionally used in the art, such as nitric acid.

[0052] According to the present invention, preferably, the amount of the adhesive solvent is 2-8% of the dry weight of the adhesive.

[0053] According to the catalyst provided by the present invention, the drying and calcination in step (2) can be carried out in accordance with conventional techniques in the art. The drying conditions include a temperature of 60-150°C and a time of 3-12 hours.

[0054] According to the present invention, preferably, the calcination conditions include a temperature of 450-650°C, more preferably 500-600°C.

[0055] According to the present invention, preferably, the roasting conditions include a time of 2-10 hours, more preferably 3-8 hours.

[0056] In this invention, the drying and calcination described in step (2) are more conducive to clearing the catalyst pores and improving the catalyst conversion efficiency during catalyst preparation.

[0057] A third aspect of the present invention provides the application of the alkyl transfer catalyst described herein in the liquid-phase alkyl transfer reaction of aromatics.

[0058] A fourth aspect of the present invention provides a method for liquid-phase alkyl transfer of aromatic hydrocarbons, the method comprising: in the presence of hydrogen, under liquid-phase reaction conditions, reacting a mixture containing toluene and C9... + A mixture of aromatics is reacted with a catalyst, wherein the alkyl transfer catalyst is the alkyl transfer catalyst described in the first aspect or the alkyl transfer catalyst prepared by the preparation method described in the second aspect.

[0059] According to the present invention, preferably, the liquid-phase reaction conditions include: a temperature of 200-350°C, more preferably 250-300°C; a pressure of 2-5 MPa, more preferably 3-4 MPa; and a mass hourly space velocity of 0.5-2.5 h⁻¹. -1 Preferably 1-2 hours -1 .

[0060] The catalyst provided by this invention is particularly suitable for liquid-phase alkyl transfer and can effectively improve the selectivity of target products and the conversion rate of aromatics.

[0061] In this invention, all reaction pressures are gauge pressures.

[0062] In particular, the method provided by this invention is especially suitable for processing mixtures containing complex aromatic components, such as C9... + Aromatic hydrocarbons, these components often appear as byproducts or raw materials in petroleum processing and chemical production. The liquid-phase alkyl transfer method of this invention can effectively transfer C9 hydrocarbons... + The alkyl moiety in aromatic hydrocarbons is transferred to smaller aromatic molecules such as toluene, thereby generating products with higher value. This process not only improves the utilization rate of raw materials but also enriches the variety of products, providing strong technical support for the deep processing and comprehensive utilization of aromatic hydrocarbons. Furthermore, this method is carried out under liquid-phase conditions, which facilitates thorough mixing and contact of reactants, improving the selectivity of xylene and the conversion rate of aromatic hydrocarbons.

[0063] C9 + Aromatic hydrocarbons refer to aromatic hydrocarbons with 9 or more carbon atoms. In this invention, C9 and C2 are mainly selected. 10 Aromatic hydrocarbons.

[0064] According to a preferred embodiment of the present invention, toluene and C9 + The mass ratio of aromatics used is 70:30 to 40:60.

[0065] The alkyl transfer catalyst provided by this invention exhibits high selectivity and high activity. Using the method provided by this invention for aromatic liquefaction alkyl transfer reactions helps reduce production costs and improve the economics of the reaction.

[0066] In this invention, the content of aromatic hydrocarbons is determined using a gas chromatograph. Testing instrument: Agilent Technologies 7890A GC System.

[0067] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this invention are based on weight, unless being based on weight would not be in accordance with the common understanding of those skilled in the art.

[0068] The present invention will be described in detail below through embodiments, but the present invention is not limited to the following embodiments.

[0069] In the following examples and comparative examples, the molecular sieve particle size analysis was obtained by observation using an XL30E scanning electron microscope from Philips GmbH, Netherlands.

[0070] In the following examples and comparative examples, the SiO2 / Al2O3 molar ratio of the molecular sieves was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Testing instrument: Varian 725-ES series ICP-AES instrument.

[0071] In the following examples and comparative examples, the content of aromatic hydrocarbons was determined using gas chromatography. Testing instrument: Agilent Technologies 7890A GC System.

[0072] Unless otherwise specified, the raw materials used in the following examples and comparative examples are all commercially available and / or prepared using methods known in the art.

[0073] In the following examples and comparative examples, the aromatic hydrocarbon conversion rate is defined as follows:

[0074]

[0075] In the following examples and comparative examples, the selectivity of xylene is defined as follows:

[0076]

[0077] Example 1

[0078] 69g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. Catalyst A was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h, as detailed in Table 1.

[0079] Example 2

[0080] 64g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 18g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. Catalyst B was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h, as detailed in Table 1.

[0081] Example 3

[0082] 72g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 10g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. Catalyst C was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h, as detailed in Table 1.

[0083] Example 4

[0084] 70g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 6.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst D was obtained, as detailed in Table 1.

[0085] Example 5

[0086] 68g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 12.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst E was obtained, as detailed in Table 1.

[0087] Example 6

[0088] 71g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 3.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst F was obtained, as detailed in Table 1.

[0089] Example 7

[0090] 65g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 12g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 20g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1.2g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst G was obtained, as detailed in Table 1.

[0091] Example 8

[0092] 69g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 15, average particle size of 200nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst H was obtained, as detailed in Table 1.

[0093] Example 9

[0094] 69g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 15, average particle size of 75nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. Catalyst I was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h, as detailed in Table 1.

[0095] Example 10

[0096] 69g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 8, average particle size of 200nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. Catalyst J was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h. See Table 1 for details.

[0097] Example 11

[0098] 69g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 13g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 8, average particle size of 75nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. After drying at 120℃ for 6h and calcining in air at 550℃ for 4h, catalyst K was obtained, as detailed in Table 1.

[0099] Comparative Example 1

[0100] 82g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid and 9.1g of copper nitrate trihydrate was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. The catalyst was obtained after drying at 120℃ for 6h and calcining in air at 550℃ for 4h. See Table 1 for details.

[0101] Comparative Example 2

[0102] 70g of dry Y zeolite (SiO2 / Al2O3 molar ratio of 10, average particle size of 250nm), 15g of dry clinoptilolite (SiO2 / Al2O3 molar ratio of 12, average particle size of 100nm), 15g of dry alumina, and 2.5g of guar gum powder were mixed evenly in a kneader. 45g of an aqueous solution containing 1g of nitric acid was slowly added to the kneader and kneaded for 30 minutes to obtain a dough-like consistency. The dough was then extruded through a mold into cylindrical strips with a diameter of 1.7mm. The catalyst was obtained by drying at 120℃ for 6h and calcining in air at 550℃ for 4h. See Table 1 for details.

[0103] Table 1

[0104]

[0105] Note: The silicon-to-aluminum ratio refers to the molar ratio of silicon oxide to aluminum oxide; the particle size refers to the average grain size of the zeolite.

[0106] Application Example 1

[0107] The catalysts of Examples 1-11 and Comparative Examples 1-2 were respectively loaded into a fixed-bed reactor and subjected to a temperature of 285°C, a pressure of 4.0 MPa, and a mass hourly space velocity of 1.5 h⁻¹. -1 The liquid-phase alkyl transfer reaction was carried out under a hydrogen atmosphere. The composition of the raw materials is shown in Table 2, and the reaction results are listed in Table 3.

[0108] Table 2

[0109] Components Toluene <![CDATA[C9 Aromatics]]> <![CDATA[C 10 Aromatic hydrocarbons content,% 50 45 5

[0110] Table 3

[0111] serial number catalyst Aromatic hydrocarbon conversion rate, % Xylene selectivity, % Example 1 A 40.1 89.1 Example 2 B 38.0 89.8 Example 3 C 39.8 85.2 Example 4 D 39.6 89.5 Example 5 E 40.5 88.8 Example 6 F 37.2 89.6 Example 7 G 37.0 89.0 Example 8 H 39.9 89.6 Example 9 I 40.2 90.0 Example 10 J 40.6 84.8 Example 11 K 40.0 84.5 Comparative Example 1 40.0 80.1 Comparative Example 2 32.2 85.0

[0112] Application Example 2

[0113] The catalysts of Examples 1-11 and Comparative Examples 1-2 were respectively loaded into a fixed-bed reactor and subjected to a temperature of 290°C, a pressure of 4.5 MPa, and a space velocity of 1.0 h⁻¹. -1 The liquid-phase alkyl transfer reaction was carried out under a hydrogen atmosphere. The composition of the raw materials is shown in Table 2, and the reaction results are listed in Table 4.

[0114] Table 4

[0115]

[0116]

[0117] Analysis of the data in the table shows that the catalyst in the comparative example had poor performance, indicating that a reasonable ratio of Y zeolite and clinoptilolite can significantly improve the aromatic hydrocarbon conversion and xylene selectivity of the catalyst. When the weight percentage of Y zeolite is between 60-70% and the weight percentage of clinoptilolite is between 12-18%, the catalyst exhibits better performance. Furthermore, the CuO content also affects the catalyst performance. A comparison of Examples 3 and 6 with Examples 1 and 2 reveals that when the amounts of each component are within the preferred range, the activity and selectivity of the catalyst are further improved. These results demonstrate that by optimizing the composition and preparation method of the catalyst, its catalytic efficiency and selectivity can be significantly improved, possessing important industrial application value and research significance.

[0118] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An alkyl transfer catalyst, characterized in that, The catalyst contains γ-zeolite, clinoptilolite, copper oxide, and a binder.

2. The catalyst according to claim 1, wherein, Based on the total amount of catalyst, the weight percentage of Y zeolite is 50-79%, preferably 60-70%; the weight percentage of clinoptilolite is 10-20%, preferably 12-18%; the weight percentage of copper oxide is 1-5%, preferably 2-4%; and the weight percentage of binder is 10-25%, preferably 10-20%. And / or, the binder is silicon dioxide and / or aluminum oxide.

3. The catalyst according to claim 1 or 2, wherein, The SiO2 / Al2O3 molar ratio of the Y zeolite is 8-20, preferably 8-15; And / or, the SiO2 / Al2O3 molar ratio of the clinoptilolite is 5-20, preferably 8-16.

4. The catalyst according to any one of claims 1-3, wherein, The average grain size of the Y zeolite is less than 500 nm, preferably 100-300 nm; And / or, the average grain size of the clinoptilolite is less than 300 nm, preferably 50-150 nm.

5. A method for preparing an alkyl transfer catalyst according to any one of claims 1-4, the method comprising the following steps: (1) In the presence of a solvent, Y zeolite, clinoptilolite, Cu precursor, binder, and optionally extrusion aid and adhesive solvent are mixed. (2) The mixture obtained in step (1) is shaped, and then dried and roasted.

6. The preparation method according to claim 5, wherein, The extrusion aid is selected from at least one of guar gum powder, methylcellulose, hydroxypropyl methylcellulose, and dextrin; Preferably, the amount of the extrusion aid is 1-5% of the total weight of Y zeolite, clinoptilolite and binder on a dry basis, and more preferably 1-3%. Preferably, the adhesive solvent is nitric acid; Preferably, the amount of adhesive solvent used is 2-8% of the dry weight of the adhesive.

7. The preparation method according to claim 5, wherein, The drying conditions include: a temperature of 60-150℃ and a time of 3-12 hours; And / or, the calcination conditions include: a temperature of 450-650℃, preferably 500-600℃; and a time of 2-10h, preferably 3-8h.

8. The use of the alkyl transfer catalyst according to any one of claims 1-4 or the alkyl transfer catalyst prepared by the method according to any one of claims 5-7 in the liquid-phase alkyl transfer reaction of aromatics.

9. A method for liquid-phase alkyl transfer of aromatic hydrocarbons, the method comprising: In the presence of hydrogen, under liquid-phase reaction conditions, a mixture containing toluene and C9 will be produced. + A mixture of aromatics is reacted with a catalyst, wherein the catalyst is selected from the alkyl transfer catalysts of any one of claims 1-4 or the alkyl transfer catalysts prepared by the method of any one of claims 5-7.

10. The method according to claim 9, wherein, The liquid-phase reaction conditions include: a temperature of 200-350℃, preferably 250-300℃; a pressure of 2-5 MPa, preferably 3-4 MPa; and a mass hourly space velocity of 0.5-2.5 h⁻¹. -1 Preferably 1-2 hours -1 .

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