Eutectic molecular sieve, its preparation method, catalyst for isomerization reaction of xylene material containing ethylbenzene and its preparation method

Abstract

The present invention relates to the technical field of isomerization catalysts, and specifically relates to a eutectic molecular sieve and a preparation method thereof, a catalyst for isomerizing a xylene material containing ethylbenzene and a preparation method thereof, and a method for isomerizing a xylene material containing ethylbenzene. The eutectic molecular sieve comprises an MFI molecular sieve and an EUO molecular sieve, and at least part of the surface of the EUO molecular sieve is covered by the MFI molecular sieve; wherein, the silica-alumina ratio of the eutectic molecular sieve is 20-200:1. After the eutectic molecular sieve provided by the present invention is hydrogenated, it is used as a carrier of a catalyst for isomerizing a xylene material containing ethylbenzene, so that the catalyst can simultaneously have the dual functions of ethylbenzene deethylation and ethylbenzene conversion to xylene, thereby effectively improving the adaptability of the raw materials.

Description

Technical Field

[0001] The present invention relates to the technical field of isomerization catalysts, and specifically relates to a eutectic molecular sieve and a preparation method thereof, a catalyst for isomerization reaction of xylene material containing ethylbenzene and a preparation method thereof, and a method for isomerization reaction of xylene material containing ethylbenzene. Background Art

[0002] p-Xylene (PX) is an important chemical raw material, mainly used for the production of terephthalic acid, terephthalic acid diester, phthalic anhydride, and is also applied in the fields of coatings, dyes, pesticides, and pharmaceuticals. With the development of these industries, the demand for PX has increased rapidly. At present, the main process technology for increasing PX production is xylene isomerization, which is an important means to convert meta-xylene and ortho-xylene with low utilization value into PX.

[0003] Through the xylene isomerization reaction, the p-xylene in the product reaches or approaches the thermodynamic equilibrium value. The PX product can be separated out by the separation device from the product, and then a small amount of light non-aromatics, benzene, toluene, and C 9 + heavy aromatics are separated out, and the remaining C 8 aromatic material can be recycled as the raw material for isomerization.

[0004] Under the existing technical conditions, it is very difficult and uneconomical to separate ethylbenzene from xylene whether by using high-efficiency rectification or adsorption separation means. Therefore, ethylbenzene must be converted simultaneously during the xylene isomerization process. There are two different target directions for ethylbenzene conversion: ethylbenzene is converted into xylene, and ethylbenzene is dealkylated to form benzene. The economy of the two directions depends on the composition of the raw materials, the energy consumption of the device, and the market conditions.

[0005] CN1887423A discloses a deethylation type isomerization catalyst for ethylbenzene, the active component of which is MFI type molecular sieve. The deethylation type catalyst has a high single-pass conversion rate of ethylbenzene, few material circulation times, and a high PX content in the adsorption feed. Therefore, in recent years, the production capacity of aromatic combined devices using deethylation type catalysts has increased.

[0006] CN102107144A discloses a conversion type isomerization catalyst for ethylbenzene, the active component of which is EUO type molecular sieve. The conversion type catalyst has a relatively low single-pass conversion rate of ethylbenzene and many material circulation times, but it can convert ethylbenzene into the target product xylene, maximizing the utilization of raw material resources. With the change of the market, when the price of C 8 aromatic raw materials is high and the benzene product is in surplus, the economy of the conversion type process will be better than that of the deethylation type process.

[0007] The comprehensive performance of the above two types of catalysts still needs to be improved. Specifically, highly active catalysts usually also lead to higher side reactions, resulting in a decrease in process selectivity and a loss of xylene yield. Modification of the acidic component zeolite is an important means to improve catalyst performance. At present, many methods have been used to modify the acidic components of catalysts. Hydrothermal modification or addition of rare earth elements to zeolites is more commonly used to modify the acidity of the active components of zeolites. The effect of modification is to optimize the acid distribution of zeolites and weaken the acid sites of side reactions.

[0008] So far, no catalyst can simultaneously have the dual functions of converting ethylbenzene to xylene or deethylating to benzene, nor is there a process for correspondingly adjusting operating conditions for raw materials with different ethylbenzene mass fractions to achieve the switching of the two routes. Therefore, there is an urgent need for a catalyst that can simultaneously deethylate ethylbenzene and convert ethylbenzene to xylene. Summary of the Invention

[0009] The object of the present invention is to overcome the problems of low raw material adaptability, low catalytic activity of the catalyst, and harsh reaction conditions of existing xylene isomerization catalysts due to their inability to simultaneously have the functions of deethylating ethylbenzene and converting ethylbenzene to xylene. The present invention provides a eutectic zeolite and its preparation method, a catalyst for isomerization reaction of xylene material containing ethylbenzene and its preparation method, and a method for isomerization reaction of xylene material containing ethylbenzene. The eutectic zeolite has a coating structure, and the catalyst containing the eutectic zeolite simultaneously has the dual functions of deethylating ethylbenzene and converting ethylbenzene to xylene, and can realize the switching of the ethylbenzene conversion route, thereby improving the adaptability of raw materials.

[0010] To achieve the above object, the first aspect of the present invention provides a eutectic zeolite, which comprises MFI zeolite and EUO zeolite, and the MFI zeolite covers at least part of the surface of the EUO zeolite;

[0011] Among them, the silica-alumina ratio of the eutectic zeolite is 20 - 200:1.

[0012] The second aspect of the present invention provides a preparation method of a eutectic zeolite, which comprises: obtaining by a one-step synthesis method using a silicon source, an aluminum source, a first structure-directing agent, a second structure-directing agent and water.

[0013] Preferably, the method comprises the following steps:

[0014] (1) Mix the silicon source, aluminum source, first structure-directing agent and water to obtain a liquid sol;

[0015] (2) Mix the liquid sol and the second structure-directing agent and carry out a synthesis reaction to obtain a eutectic zeolite.

[0016] The third aspect of the present invention provides a catalyst for isomerization reaction of xylene materials containing ethylbenzene, and the catalyst comprises a carrier and a metal component supported on the carrier; wherein, the carrier comprises a hydrogen-type eutectic molecular sieve and a binder;

[0017] Wherein, the hydrogen-type eutectic molecular sieve is obtained by hydrogenation treatment of the eutectic molecular sieve described in the first aspect or the eutectic molecular sieve prepared by the method provided in the second aspect.

[0018] The fourth aspect of the present invention provides a preparation method of a catalyst for isomerization reaction of xylene materials containing ethylbenzene, and the method comprises the following steps:

[0019] (I-a) Subjecting the eutectic molecular sieve to a first ion exchange, a first washing, a first drying, a first calcination, and a first shaping in sequence to obtain a carrier; or,

[0020] (I-b) Subjecting the eutectic molecular sieve to a second shaping, a second ion exchange, a second washing, a second drying, and a second calcination in sequence to obtain a carrier;

[0021] (II) Immersing the carrier in a soluble metal salt solution, and subjecting the obtained product to activation reduction to obtain a catalyst;

[0022] Wherein, the eutectic molecular sieve is the eutectic molecular sieve provided in the first aspect or the eutectic molecular sieve prepared by the method provided in the second aspect.

[0023] The fifth aspect of the present invention provides a method for isomerization reaction of xylene materials containing ethylbenzene, and the method comprises: in the presence of hydrogen, bringing the xylene materials containing ethylbenzene into contact with a catalyst and carrying out a reaction;

[0024] Wherein, the catalyst is the catalyst provided in the third aspect or the catalyst prepared by the method provided in the fourth aspect.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] (1) The eutectic molecular sieve provided by the present invention comprises an MFI molecular sieve and an EUO molecular sieve, and the MFI molecular sieve covers at least part of the surface of the EUO molecular sieve, so that the eutectic molecular sieve simultaneously has the pore structures of the MFI molecular sieve and the EUO molecular sieve; in particular, considering the crystal grain size of the MFI molecular sieve, the crystal grain size of the EUO molecular sieve, and the silica-alumina ratio of the eutectic molecular sieve, the eutectic molecular sieve has two completely different pore structures; meanwhile, the eutectic molecular sieve is prepared by a one-step synthesis method, which simplifies the process flow;

[0027] (2) After subjecting the eutectic molecular sieve provided by the present invention to hydrogenation treatment, it is used as a carrier for a catalyst in the isomerization reaction of xylene materials containing ethylbenzene, so that the catalyst can have a molecular sieve pore structure suitable for two routes; in particular, in combination with the content of each component in the catalyst, the catalytic activity of the catalyst is further improved;

[0028] (3) The catalyst provided by the present invention is used in the isomerization reaction of xylene materials containing ethylbenzene. Since the catalyst has the dual functions of ethylbenzene deethylation and ethylbenzene conversion to xylene, the adaptability of the raw materials can be effectively improved; at the same time, in combination with the content of ethylbenzene in the raw materials, the reaction conditions are adjusted accordingly to achieve the switching of the two routes. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the XRD pattern of the eutectic molecular sieve S1 prepared in Preparation Example 1;

[0030] Figure 2 It is the SEM pattern of the eutectic molecular sieve S1 prepared in Preparation Example 1;

[0031] Figure 3 It is the XRD pattern of the eutectic molecular sieve S2 prepared in Preparation Example 2;

[0032] Figure 4 It is the SEM pattern of the eutectic molecular sieve S2 prepared in Preparation Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0033] In the ranges disclosed herein, the endpoints and any values are not limited to the exact 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 each range, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0034] In the present invention, unless otherwise specified, the "first" and "second" do not represent the order of precedence, nor do they limit each material or step. They are only used to distinguish each material or step. For example, the "first" and "second" in "first ion exchange" and "second ion exchange" are only used to distinguish that these are not the same ion exchange.

[0035] The first aspect of the present invention provides a eutectic molecular sieve, which comprises MFI molecular sieve and EUO molecular sieve, and the MFI molecular sieve covers at least part of the surface of the EUO molecular sieve;

[0036] Among them, the silica-alumina ratio of the eutectic molecular sieve is 20-200:1.

[0037] The inventors of the present invention have found through research that in the xylene isomerization process with a wide range of feedstock adaptability, the technical difficulty lies in that the catalyst must simultaneously have a zeolite pore structure suitable for two routes and precisely adjust the acid center distribution. In view of the different reaction difficulties of the two routes (ethylbenzene deethylation and ethylbenzene conversion to xylene), simply mixing two zeolites cannot achieve process switching with high selectivity. In summary, by using an optimized synthesis method, a eutectic zeolite with a special size and coating structure is prepared, and through optimizing the ion exchange technology, an organic amine structure-directing agent with diffusion resistance limitation is selected as the ammonium exchange reagent to precisely control the distribution of acid centers, so as to achieve a wide range of feedstock adaptability on a single catalyst.

[0038] In the present invention, unless otherwise specified, the eutectic zeolite comprises MFI zeolite and EUO zeolite, and the MFI zeolite covers at least part of the surface of the EUO zeolite. That is, the eutectic zeolite provided by the present invention has a core-shell structure, with the EUO zeolite as the core and the MFI zeolite as the shell.

[0039] In the present invention, unless otherwise specified, the MFI zeolite includes but is not limited to ZSM-5 zeolite; the EUO zeolite includes but is not limited to Eu-1 zeolite.

[0040] In some embodiments of the present invention, preferably, the silica-alumina ratio of the eutectic zeolite is 20-200:1, for example, 20:1, 25:1, 30:1, 50:1, 70:1, 100:1, 150:1, 200:1, and any value within the range composed of any two values, preferably 25-70:1.

[0041] In some embodiments of the present invention, preferably, the crystal grain size of the MFI zeolite in the eutectic zeolite is 20-300 nm, for example, 20 nm, 50 nm, 80 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, and any value within the range composed of any two values, preferably 50-100 nm.

[0042] In some embodiments of the present invention, preferably, the crystal grain size of the EUO zeolite in the eutectic zeolite is 0.5-3 μm, for example, 0.5 μm, 0.8 μm, 1 μm, 1.5 μm, 1.8 μm, 2 μm, 3 μm, and any value within the range composed of any two values, preferably 0.8-1.8 μm.

[0043] According to a particularly preferred embodiment of the present invention, the eutectic zeolite comprises MFI zeolite and EUO zeolite, and the MFI zeolite coats the EUO zeolite;

[0044] Among them, the silica-alumina ratio of the eutectic molecular sieve is 20 - 200:1;

[0045] Among them, the crystal grain size of the MFI molecular sieve in the eutectic molecular sieve is 20 - 300 nm; the crystal grain size of the EUO molecular sieve in the eutectic molecular sieve is 0.5 - 3 μm;

[0046] Among them, the eutectic molecular sieve is prepared by the following method: a silicon source, an aluminum source, a first structure-directing agent, a second structure-directing agent and water are prepared by a one-step synthesis method;

[0047] Among them, the general formula of the first structure-directing agent is N(R 1 ) 3 + C n H 2n N(R 2 ) 3 + ·2X - , where R 1 and R 2 are each independently an alkyl group of C 1 -C 4 , n is 2 - 10, and X is a halogen;

[0048] Among them, the general formula of the second structure-directing agent is N(R 3 ) 4 + ·Y - , where R 3 is an alkyl group of C 1 -C 4 , and Y is a halogen.

[0049] The second aspect of the present invention provides a method for preparing a eutectic molecular sieve, the method comprising: a silicon source, an aluminum source, a first structure-directing agent, a second structure-directing agent and water are prepared by a one-step synthesis method.

[0050] According to the present invention, preferably, the method comprises the following steps:

[0051] (1) Mix the silicon source, aluminum source, first structure-directing agent and water to obtain a liquid sol;

[0052] (2) Mix the liquid sol and the second structure-directing agent and carry out a synthesis reaction to obtain a eutectic molecular sieve.

[0053] In the present invention, there is a wide range of choices for the mixing method, as long as the silicon source, aluminum source, first structure-directing agent, and water are mixed evenly. Preferably, in step (1), the mixing process includes: (1-a) dissolving the first structure-directing agent in the water to obtain a solution; (1-b) adding the aluminum source to the solution, and then adding the silicon source to obtain the sol.

[0054] In some embodiments of the present invention, preferably, the conditions for the synthesis reaction include: the temperature is 140 - 190 °C, preferably 165 - 175 °C; the time is 20 - 40 h, preferably 25 - 35 h.

[0055] In some embodiments of the present invention, preferably, the amounts of the silicon source, aluminum source, first structure-directing agent, second structure-directing agent, and water satisfy that the molar ratio of Na 2 O:SiO 2 :Al 2 O 3 : first structure-directing agent: second structure-directing agent: H 2 O is 0.25 - 0.5:1:0.005 - 0.05:0.02 - 0.22:0.02 - 0.12:20 - 50, preferably 0.28 - 0.4:1:0.01 - 0.02:0.02 - 0.22:0.02 - 0.12:20 - 40.

[0056] In the present invention, there is a wide range of choices for the silicon source. Preferably, the silicon source is water glass, and the molar ratio of SiO 2 and Na 2 O in the water glass is 2 - 4:1. For example, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, and any value within the range composed of any two values, preferably 2.5 - 3.5:1.

[0057] In the present invention, there is a wide range of choices for the type of the aluminum source. Preferably, the aluminum source is selected from at least one of aluminum sulfate, aluminum nitrate, and aluminum chloride.

[0058] In the present invention, the first structure-directing agent is used to promote the formation of EUO zeolite seeds. Preferably, the general formula of the first structure-directing agent is N(R 1 ) 3 + C n H 2n N(R 2 ) 3 + ·2X - wherein, R 1 and R 2 are each independently C1 -C 4 alkyl group, preferably methyl and / or ethyl, n is 2 - 10, X is halogen, preferably selected from chlorine and / or bromine.

[0059] In the present invention, the second structure - directing agent is used to promote the formation of seeds of MFI zeolite. Preferably, the general formula of the second structure - directing agent is N(R 3 ) 4 + ·Y - , wherein, R 3 is C 1 -C 4 alkyl group, preferably ethyl and / or propyl, Y is halogen, preferably selected from chlorine and / or bromine.

[0060] The third aspect of the present invention provides a catalyst for isomerization reaction of xylene material containing ethylbenzene, the catalyst comprises a carrier and a metal component supported on the carrier; wherein, the carrier comprises a hydrogen - type eutectic zeolite and a binder;

[0061] Wherein, the hydrogen - type eutectic zeolite is obtained by subjecting the eutectic zeolite provided by the first aspect or the eutectic zeolite prepared by the method provided by the second aspect to hydrogenation treatment.

[0062] In some embodiments of the present invention, preferably, based on the total weight of the catalyst, the content of the hydrogen - type eutectic zeolite is 20 - 90 wt%, preferably 50 - 80 wt%; the content of the binder is 9.94 - 75 wt%, preferably 19.95 - 49.75 wt%; the content of the metal component is 0.01 - 5 wt%, preferably 0.05 - 0.25 wt%.

[0063] In some embodiments of the present invention, preferably, the molar content of Na 2 O in the hydrogen - type eutectic zeolite is 0.01 - 2%, for example, 0.01%, 0.1%, 0.2%, 0.4%, 0.5%, 1%, 2%, and any value within the range composed of any two of these values, preferably 0.1 - 0.4%. Adopting the preferred conditions is more conducive to controlling the total acid amount of the catalyst within a reasonable range and avoiding side reactions caused by excessive strong acid amount.

[0064] In the present invention, there is a wide selection range for the manner of the hydrogenation treatment, as long as the eutectic zeolite is converted from Na - type eutectic zeolite to hydrogen - type eutectic zeolite, that is, making the Na 2The O molar content is 0.01 - 2%, for example, 0.01%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 1%, 1.5%, 2%, and any value within the range composed of any two numerical values, preferably 0.1 - 0.4%.

[0065] In some embodiments of the present invention, preferably, the binder is selected from alumina.

[0066] In some embodiments of the present invention, preferably, the metal component is platinum.

[0067] The fourth aspect of the present invention provides a method for preparing a catalyst for isomerization reaction of xylene materials containing ethylbenzene, and the method includes the following steps:

[0068] (I-a) Subjecting the eutectic zeolite to first ion exchange, first washing, first drying, first calcination, and first shaping in sequence to obtain a carrier; or,

[0069] (I-b) Subjecting the eutectic zeolite to second shaping, second ion exchange, second washing, second drying, and second calcination in sequence to obtain a carrier;

[0070] (II) Immersing the carrier in a soluble metal salt solution, and subjecting the obtained product to activation and reduction in sequence to obtain a catalyst;

[0071] Wherein, the eutectic zeolite is the eutectic zeolite provided in the first aspect, or the eutectic zeolite prepared by the method provided in the second aspect.

[0072] In some embodiments of the present invention, preferably, in step (I-a), the process of the first ion exchange includes: performing the first ion exchange on the eutectic zeolite with an aqueous solution of a second structure-directing agent. Wherein, the first ion exchange aims to use the second structure-directing agent with diffusion resistance limitation as an ammonium exchange reagent to precisely regulate the distribution of acid centers, so that the eutectic zeolite has the dual functions of ethylbenzene deethylation and ethylbenzene conversion to xylene.

[0073] In the present invention, without special description, the types of the second structure-directing agent are in accordance with the above limitations, and the present invention will not elaborate herein.

[0074] In some embodiments of the present invention, preferably, the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the eutectic zeolite in g is 1 - 50:1, for example, 1:1, 5:1, 10:1, 20:1, 30:1, 40:1, 50:1, and any value within the range composed of any two numerical values, preferably 5 - 30:1.

[0075] In some embodiments of the present invention, preferably, in the aqueous solution of the second structure-directing agent, the concentration of the second structure-directing agent is 0.01 - 0.08 mol / L, for example, 0.01 mol / L, 0.04 mol / L, 0.05 mol / L, 0.06 mol / L, 0.08 mol / L, and any value within the range composed of any two of these values, preferably 0.04 - 0.06 mol / L.

[0076] In the present invention, the first washing aims to remove the residual second structure-directing agent in the product of the first ion exchange. Preferably, the process of the first washing includes: washing the product of the first ion exchange with deionized water such that there are no halogen ions in the wash liquid and the pH of the wash liquid is 6 - 8. In the present invention, the number of times of the first washing is not limited as long as there are no halogen ions in the wash liquid and the pH of the wash liquid is 6 - 8.

[0077] In some embodiments of the present invention, preferably, the molar content of Na 2 O in the product of the first washing is 0.01 - 2%, for example, 0.01%, 0.1%, 0.2%, 0.4%, 0.5%, 1%, 2%, and any value within the range composed of any two of these values, preferably 0.1 - 0.4%.

[0078] In the present invention, the first drying and the first calcination aim to dry and calcine the product of the first washing. Preferably, the conditions for the first drying include: temperature 80 - 150°C, preferably 90 - 120°C; time 1 - 24 h, preferably 5 - 20 h; the conditions for the first calcination include: temperature 400 - 600°C, preferably 450 - 550°C; time 1 - 24 h, preferably 5 - 15 h.

[0079] In some embodiments of the present invention, preferably, the process of the first shaping includes: mixing the product of the first calcination with a binder and an acid solution, and the resulting mixture is extruded into shape. Further preferably, the weight ratio of the product of the first calcination, the binder, and the acid solution is 1:0.11 - 4:0.1 - 2, preferably 1:0.25 - 1:0.3 - 1.2.

[0080] In the present invention, without special instructions, the types of the binder are all in accordance with the above limitations, and the present invention will not elaborate herein.

[0081] In some embodiments of the present invention, preferably, the acid solution is an inorganic acid solution; further preferably, the concentration of the acid in the acid solution is 0.2 - 2 mol / L, preferably 0.5 - 1.5 mol / L, wherein the acid is selected from at least one of hydrochloric acid, nitric acid, and sulfuric acid, preferably nitric acid.

[0082] In some embodiments of the present invention, preferably, in step (I-b), the process of the second shaping includes: mixing the eutectic molecular sieve with a binder and an acid solution, and extruding and shaping the obtained mixture.

[0083] In some embodiments of the present invention, preferably, the weight ratio of the eutectic molecular sieve, the binder and the acid solution is 1: 0.11-4: 0.1-2, preferably 1: 0.25-1: 0.3-1.2.

[0084] In some embodiments of the present invention, preferably, before the second ion exchange, the product of the second shaping is dried at 80-150 °C for 1-24 h, preferably dried at 90-120 °C for 5-20 h.

[0085] In some embodiments of the present invention, preferably, the process of the second ion exchange includes: performing a second ion exchange on an aqueous solution of a second structure-directing agent and the product of the second shaping.

[0086] In the present invention, without special description, the aqueous solution of the second structure-directing agent and the second structure-directing agent are both in accordance with the above definitions, and the present invention will not elaborate herein.

[0087] In some embodiments of the present invention, preferably, the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the product of the second shaping in g is 1-50: 1, for example, 1: 1, 5: 1, 10: 1, 20: 1, 30: 1, 40: 1, 50: 1, and any value within the range composed of any two values, preferably 5-30: 1.

[0088] In some embodiments of the present invention, preferably, the process of the second washing includes: washing the product of the second ion exchange with deionized water until there are no halogen ions in the wash liquid and the pH of the wash liquid is 6-8.

[0089] In some embodiments of the present invention, preferably, the molar content of Na 2 O in the product of the second washing is 0.01-2%, for example, 0.01%, 0.1%, 0.2%, 0.4%, 0.5%, 1%, 2%, and any value within the range composed of any two values, preferably 0.1-0.4%.

[0090] In the present invention, the second drying and the second calcination are intended to dry and calcine the product of the second washing. Preferably, the conditions for the second drying include: a temperature of 80 - 150°C, preferably 90 - 120°C; a time of 1 - 24 h, preferably 5 - 20 h; the conditions for the second calcination include: a temperature of 400 - 600°C, preferably 450 - 550°C; a time of 1 - 24 h, preferably 5 - 15 h.

[0091] In some embodiments of the present invention, preferably, the conditions for the first ion exchange and the second ion exchange each independently include: a temperature of 50 - 100°C, preferably 60 - 90°C; the number of times ≥ 1, preferably 2 - 4 times.

[0092] In the present invention, in step (II), impregnation is used to load a soluble metal salt on the surface of the carrier, and the soluble metal salt loaded in the product is converted into elemental metal by activation and reduction.

[0093] In the present invention, unless otherwise specified, "soluble" means being easily soluble in water or being easily soluble in water under the action of an auxiliary agent.

[0094] In some embodiments of the present invention, preferably, in the soluble metal salt solution in step (II), the metal concentration in the soluble metal salt is 0.2 - 5 g / L, for example, 0.2 g / L, 0.5 g / L, 1 g / L, 1.5 g / L, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 5 g / L, and any value within the range composed of any two values, preferably 0.5 - 3.5 g / L.

[0095] In some embodiments of the present invention, preferably, the soluble metal salt is hexachloroplatinic acid hydrochloride.

[0096] In some embodiments of the present invention, preferably, the dosage ratio of the carrier in g to the soluble metal salt solution in mL is 1:1 - 5, for example, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:4, 1:5, and any value within the range composed of any two values, preferably 1:1 - 2.5.

[0097] In some embodiments of the present invention, preferably, the conditions for activation include: a temperature of 400 - 550°C, preferably 450 - 525°C; a time of 2 - 8 h, preferably 3 - 6 h; the conditions for reduction include: a temperature of 350 - 520°C, preferably 420 - 480°C; a time of 1 - 5 h, preferably 1 - 4 h.

[0098] The catalyst provided by the present invention has the dual functions of ethylbenzene deethylation and ethylbenzene conversion to xylene. When it is used in the xylene isomerization reaction containing ethylbenzene, when the content of ethylbenzene in the xylene containing ethylbenzene is low, the catalyst has the catalytic activity of ethylbenzene deethylation; when the content of ethylbenzene in the xylene containing ethylbenzene is high, the catalyst has the catalytic activity of ethylbenzene conversion to xylene. That is, the catalyst provided by the present invention can realize the switching of the ethylbenzene conversion route, thereby effectively improving the adaptability of the raw materials.

[0099] The fifth aspect of the present invention provides a method for isomerization reaction of a xylene material containing ethylbenzene, which includes: in the presence of hydrogen, contacting and reacting the xylene material containing ethylbenzene with a catalyst;

[0100] Wherein, the catalyst is the catalyst provided by the third aspect, or the catalyst prepared by the method provided by the fourth aspect.

[0101] In some embodiments of the present invention, preferably, in the xylene material containing ethylbenzene, the content of ethylbenzene is 1-20 wt%, for example, 1 wt%, 2 wt%, 3 wt%, 5 wt%, 8 wt%, 10 wt%, 15 wt%, 20 wt%, and any value within the range composed of any two numerical values.

[0102] In a preferred embodiment of the present invention, preferably, when the content of ethylbenzene in the xylene material containing ethylbenzene is 1-10 wt%, the reaction is an ethylbenzene deethylation reaction; further preferably, the conditions of the ethylbenzene deethylation reaction include: the temperature is 355-375 °C; the pressure is 0.4-0.8 MPa; the weight hourly space velocity is 6-10 h -1 ; the hydrogen-hydrocarbon molar ratio is 0.8-1.5:1. Wherein, the hydrogen-hydrocarbon molar ratio refers to the molar ratio of hydrogen and the xylene material containing ethylbenzene.

[0103] In another preferred embodiment of the present invention, preferably, when the content of ethylbenzene in the xylene material containing ethylbenzene is 10-20 wt%, the reaction is an ethylbenzene to xylene reaction; further preferably, the conditions of the ethylbenzene to xylene reaction include: the temperature is 375-395 °C; the pressure is 0.8-1.5 MPa; the weight hourly space velocity is 3-6 h -1 ; the hydrogen-hydrocarbon molar ratio is 2.5-3.5:1. Wherein, the hydrogen-hydrocarbon molar ratio refers to the molar ratio of hydrogen and the xylene material containing ethylbenzene.

[0104] The present invention will be described in detail below through examples.

[0105] Preparation Example 1

[0106] In a 2 L reaction kettle, 450 mL of a silicon source (sodium silicate, concentration 24 wt%, SiO2 and Na 2 O molar ratio of 3.1), 20.2 g of aluminum source (aluminum sulfate), 10.9 g of the first structure-directing agent (N(CH 3 ) 3 + C 6 H 12 N(CH 3 ) 3 + ·2Cl - )、63.9 g of the second structure-directing agent (N(C 3 H 7 ) 4 + ·Br - ), where the dosages of the fed substances satisfy: Na 2 O:SiO 2 :Al 2 O 3 : the first structure-directing agent: the second structure-directing agent: H 2 O molar ratio of 0.32:1:0.015:0.02:0.12:25; then a synthesis reaction is carried out at 175 °C for 35 h to obtain the eutectic zeolite S1.

[0107] Among them, the XRD pattern of the eutectic zeolite S1 is as shown in Figure 1 , and it can be seen from Figure 1 that in the range of 2θ from 5 to 50°, the eutectic zeolite S1 simultaneously has the characteristic peaks of ZSM-5 zeolite and Eu-1 zeolite.

[0108] Among them, the SEM image of the eutectic zeolite S1 is as shown in Figure 2 , and it can be seen from Figure 2 that in the eutectic zeolite S1, the ZSM-5 zeolite covers the surface of the Eu-1 zeolite, the silica-alumina ratio of the eutectic zeolite S1 is 60, the particle size of the ZSM-5 zeolite is 100 nm, and the particle size of the Eu-1 zeolite is 1.8 μm.

[0109] Preparation Example 2

[0110] In a 2 L reaction kettle, 450 mL of a silicon source (sodium silicate, concentration 24 wt%, SiO 2 and Na 2 O molar ratio of 3.1), 26.6 g of aluminum source (aluminum sulfate), 159.4 g of the first structure-directing agent (N(CH 3 ) 3 + C 6 H 12 N(CH 3 ) 3 +·2Br - )、6.6 g of the second structure-directing agent (N(C 2 H 5 ) 4 + Cl - ), where the dosages of the charged substances satisfy: Na 2 O:SiO 2 :Al 2 O 3 : the first structure-directing agent: the second structure-directing agent: H 2 O has a molar ratio of 0.32:1:0.02:0.22:0.02:35; then a synthesis reaction is carried out at 165 °C for 25 h to obtain the eutectic molecular sieve S2.

[0111] Among them, the XRD pattern of the eutectic molecular sieve S2 is as Figure 3 shown, and it can be seen from Figure 3 that in the range of 2θ from 5 to 50°, the eutectic molecular sieve S2 simultaneously has the characteristic peaks of ZSM-5 molecular sieve and Eu-1 molecular sieve.

[0112] Among them, the SEM pattern of the eutectic molecular sieve S2 is as Figure 4 shown, and it can be seen from Figure 4 that in the eutectic molecular sieve S2, the ZSM-5 molecular sieve covers the surface of the Eu-1 molecular sieve. The silica-alumina ratio of the eutectic molecular sieve S2 is 50. The particle size of the ZSM-5 molecular sieve is 80 nm, and the particle size of the Eu-1 molecular sieve is 1.2 μm.

[0113] Example 1

[0114] (1) Mix 14 g of the eutectic molecular sieve S1 with 5.99 g of a binder (aluminum oxide) and an acid solution (an aqueous nitric acid solution with a concentration of 1 mol / L). Among them, the weight ratio of the eutectic molecular sieve S1, the binder, and the acid solution is 1:0.428:0.5. The obtained mixture is extruded and formed, and the resulting product is dried at 120 °C for 8 h, then pelletized, dried at 540 °C for 4 h, and the obtained formed product is subjected to ion exchange with an aqueous solution of the second structure-directing agent (the second structure-directing agent: N(C 3 H 7 ) 4 + Br - , with a concentration of 0.05 mol / L). Among them, the ion exchange temperature is 90 °C, and the number of exchange times is 2. The volume ratio of the aqueous solution of the second structure-directing agent in mL to the formed product in g is 30:1; the ion-exchanged product is washed with deionized water until no bromide ions are detected in the wash liquor and the pH is 7.8. The Na 2The O molar content is 0.13%; the washed product is dried at 120 °C for 24 h, and then calcined at 540 °C for 24 h in a muffle furnace under an air atmosphere to obtain a support;

[0115] (2) Immerse 19.99 g of the support in 20 mL of an aqueous solution of hexachloroplatinic acid (Pt concentration is 0.5 g / L). First, activate the impregnated product in air at 525 °C for 2 h, and then reduce it in a hydrogen atmosphere at 420 °C for 4 h to obtain catalyst P1.

[0116] Among them, in catalyst P1, based on the total weight of catalyst P1, the content of platinum is 0.05 wt%, and the content of hydrogen-type eutectic molecular sieve is 70 wt%.

[0117] Example 2

[0118] (1) An aqueous solution of 14 g of the second structure-directing agent of eutectic molecular sieve S1 (second structure-directing agent: N(C 3 H 7 ) 4 + Cl - , with a concentration of 0.046 mol / L) is subjected to ion exchange. Among them, the ion exchange temperature is 90 °C, the number of exchanges is 2 times, and the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the shaped product in g is 23:1; the ion-exchanged product is washed with deionized water until no chloride ions are detected in the wash liquor and the pH is 7.5. The Na 2 O molar content in the washed product is 0.1%; the washed product is dried at 120 °C for 24 h, and then calcined at 540 °C for 24 h in a muffle furnace under an air atmosphere to obtain a calcined product; the calcined product is fully mixed with 5.99 g of a binder (aluminum oxide), and then mixed with an acid solution (an aqueous nitric acid solution with a concentration of 0.5 mol / L). Among them, the weight ratio of the calcined product, the binder, and the acid solution is 1:0.429:0.3. The obtained mixture is extruded into shape, and the obtained product is pelletized and calcined to obtain a support;

[0119] (2) Immerse 19.99 g of the support in 20 mL of an aqueous solution of hexachloroplatinic acid (Pt concentration is 0.5 g / L). First, activate the impregnated product in air at 450 °C for 8 h, and then reduce it in a hydrogen atmosphere at 480 °C for 1 h to obtain catalyst P2.

[0120] Among them, in catalyst P2, based on the total weight of catalyst P2, the content of platinum is 0.05 wt%, and the content of hydrogen-type eutectic molecular sieve is 70 wt%.

[0121] Example 3

[0122] (1) Mix 14 g of eutectic molecular sieve S2 with 5.95 g of binder (aluminum oxide) and acid solution (nitric acid aqueous solution with a concentration of 1.5 mol / L). Among them, the weight ratio of eutectic molecular sieve S1, binder, and acid solution is 1:0.425:1. The obtained mixture is extruded and formed, and the resulting product is dried at 120 °C for 8 h, then pelletized, dried at 540 °C for 4 h, and the obtained formed product is ion-exchanged with an aqueous solution of the second structure-directing agent (the second structure-directing agent: N(C 2 H 5 ) 4 + Br - , with a concentration of 0.04 mol / L). Among them, the ion-exchange temperature is 90 °C, and the number of exchange times is 2 times. The dosage ratio of the aqueous solution of the second structure-directing agent in mL to the formed product in g is 5:1; the ion-exchanged product is washed with deionized water until no bromide ions are detected in the wash liquor and the pH is 6.3. The Na 2 O molar content in the washed product is 0.37%; the washed product is dried at 120 °C for 24 h and then calcined at 540 °C for 24 h in a muffle furnace under an air atmosphere to obtain a carrier;

[0123] (2) Immerse 19.95 g of the carrier in 20 mL of an aqueous solution of hexachloroplatinate hydrochloride (Pt concentration is 2.5 g / L). The impregnated product is first activated in air at 500 °C for 5 h and then reduced in a hydrogen atmosphere at 450 °C for 2 h to obtain catalyst P3.

[0124] Among them, in catalyst P3, based on the total weight of catalyst P3, the content of platinum is 0.25 wt%, and the content of hydrogen-type eutectic molecular sieve is 70 wt%.

[0125] Example 4

[0126] According to the method of Example 3, the difference is that in step (1), the second structure-directing agent in the aqueous solution of the second structure-directing agent is N(C 2 H 5 ) 4 + Cl - , with a concentration of 0.042 mol / L, and the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the formed product in g is 16:1; the ion-exchanged product is washed with deionized water until no bromide ions are detected in the wash liquor and the pH is 7.5. The other steps are the same to obtain catalyst P4.

[0127] Among them, in catalyst P4, based on the total weight of catalyst P4, the content of platinum is 0.25 wt%, and the content of hydrogen-type eutectic molecular sieve is 70 wt%.

[0128] Comparative Example 1

[0129] (1) Mix 14 g of MFI zeolite (silica-alumina ratio of 60) and 5.996 g of alumina thoroughly, then add 20 mL of 3% nitric acid aqueous solution and mix to form a viscous mixture. Extrude the mixture into bars, dry the bars at 120 °C for 6 h, then cut into pellets and calcine at 540 °C for 4 h; perform ion exchange with 50 mL of 0.05 mol / L ammonium chloride aqueous solution at 90 °C for 2 h, twice, and wash until there is no chloride ion in the mother liquor to obtain the support.

[0130] (2) Immerse the above support in 20 mL of hexachloroplatinic acid hydrochloride aqueous solution (Pt concentration is 0.2 g / L). First, activate the impregnated product in air at 500 °C for 6 h, and then reduce it in a hydrogen atmosphere at 500 °C for 4 h to obtain catalyst DP1.

[0131] Among them, in catalyst DP1, based on the total weight of catalyst DP1, the content of platinum is 0.02 wt%, and the content of hydrogen-form MFI zeolite is 70 wt%.

[0132] Comparative Example 2

[0133] (1) Perform ion exchange on 14 g of EUO zeolite (silica-alumina ratio of 50) with 50 mL of 0.05 mol / L ammonium chloride aqueous solution at 90 °C for 2 h, twice, and wash until there is no chloride ion in the mother liquor, then dry at 120 °C for 6 h; thoroughly mix the washed zeolite with 5.996 g of alumina, then add 20 mL of 3% nitric acid aqueous solution and mix to form a viscous mixture. Extrude the mixture into bars, dry the bars at 120 °C for 6 h, then cut into pellets and calcine at 540 °C for 4 h to obtain the support.

[0134] (2) Immerse the above support in 20 mL of hexachloroplatinic acid hydrochloride aqueous solution (Pt concentration is 0.2 g / L). First, activate the impregnated product in air at 480 °C for 5 h, and then reduce it in a hydrogen atmosphere at 480 °C for 4 h to obtain catalyst DP2.

[0135] Among them, in catalyst DP2, based on the total weight of catalyst DP2, the content of platinum is 0.02 wt%, and the content of hydrogen-form EUO zeolite is 70 wt%.

[0136] Test Example

[0137] Perform catalytic performance tests on the catalysts (P1 - P4 and DP1 - DP2) prepared in Examples 1 - 4 and Comparative Examples 1 - 2.

[0138] Test conditions: In a continuous-flow fixed-bed micro-hydrogenation unit, catalysts (P1 - P4 and DP1 - DP2) were loaded respectively, and catalytic evaluations were carried out using two industrial xylene materials. That is, the specific compositions of Material 1 and Material 2 are listed in Table 1, and the reaction conditions and reaction results are both listed in Table 2.

[0139] The performance of the catalyst was evaluated according to the following calculation methods:

[0140] Isomerization equilibrium attainment rate:

[0141] Xylene yield:

[0142] Ethylbenzene conversion rate:

[0143] Table 1

[0144]

[0145] Table 2

[0146]

[0147] Note: * refers to having ZSM-5 molecular sieve / Eu-1 molecular sieve.

[0148] Continued Table 2

[0149]

[0150] Note: * refers to having ZSM-5 molecular sieve / Eu-1 molecular sieve.

[0151] From the results in Table 2, it can be seen that compared with Comparative Examples 1 - 2, the catalyst provided by the present invention has the dual functions of ethylbenzene de-ethylation and ethylbenzene conversion to xylene. Specifically, compared with Comparative Example 1, under the ethylbenzene de-ethylation reaction conditions, the eutectic molecular sieve provided by the present invention has a comparable ethylbenzene conversion rate; under the ethylbenzene conversion to xylene reaction conditions, the eutectic molecular sieve provided by the present invention has a higher xylene yield; compared with Comparative Example 2, under the ethylbenzene de-ethylation reaction conditions, the eutectic molecular sieve provided by the present invention has a higher ethylbenzene conversion rate; under the ethylbenzene conversion to xylene reaction conditions, the eutectic molecular sieve provided by the present invention has a comparable xylene yield. Therefore, the eutectic molecular sieve provided by the present invention can switch the ethylbenzene conversion route according to the ethylbenzene content in the raw material, thereby improving the raw material adaptability of the catalyst.

[0152] 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 technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including the combination of each technical feature in any other suitable manner. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A eutectic molecular sieve, characterized in that, the eutectic molecular sieve comprises MFI molecular sieve and EUO molecular sieve, and the MFI molecular sieve covers at least part of the surface of the EUO molecular sieve; wherein, the silica-alumina ratio of the eutectic molecular sieve is 20 - 200:1; Among them, the eutectic molecular sieve is prepared by the following method: obtained by one-step synthesis from a silicon source, an aluminum source, a first structure-directing agent, a second structure-directing agent, and water; wherein, the amounts of the silicon source, aluminum source, first structure-directing agent, second structure-directing agent, and water satisfy that Na 2 O:SiO 2 :Al 2 O 3 : the first structure-directing agent: the second structure-directing agent: H 2 O has a molar ratio of 0.25 - 0.5:1:0.005 - 0.05:0.02 - 0.22:0.02 - 0.12:20 - 50; wherein, the general formula of the first structure-directing agent is N(R 1 ) 3 + C n H 2n N(R 2 ) 3 + ·2X - , R 1 and R 2 are each independently an alkyl group of C 1 -C 4 , n is 2 - 10, and X is a halogen; the general formula of the second structure-directing agent is N(R 3 ) 4 + ·Y - , R 3 is an alkyl group of C 1 -C 4 , and Y is a halogen.

2. The eutectic molecular sieve according to claim 1, wherein, the silica-alumina ratio of the eutectic molecular sieve is 25 - 70:

1.

3. The eutectic molecular sieve according to claim 1, wherein, the crystal grain size of the MFI molecular sieve in the eutectic molecular sieve is 20 - 300 nm; and / or, the crystal grain size of the EUO molecular sieve in the eutectic molecular sieve is 0.5 - 3 µm.

4. The eutectic molecular sieve according to claim 3, wherein, the crystal grain size of the MFI molecular sieve in the eutectic molecular sieve is 50 - 100 nm; and / or, the crystal grain size of the EUO molecular sieve in the eutectic molecular sieve is 0.8 - 1.8 µm.

5. A preparation method of the eutectic molecular sieve according to any one of claims 1 - 4, characterized in that, the method comprises the following steps: (1) Mix the silicon source, aluminum source, first structure-directing agent and water to obtain a liquid sol; (2) Mix the liquid sol and the second structure-directing agent and carry out a synthesis reaction to obtain the eutectic molecular sieve.

6. The method according to claim 5, wherein, in step (1), the mixing process comprises: (1-a) Dissolve the first structure-directing agent in the water to obtain a solution; (1-b) Add the aluminum source to the solution, and then add the silicon source to obtain the liquid sol; and / or, the conditions of the synthesis reaction include: the temperature is 140 - 190 °C; the time is 20 - 40 h.

7. The method according to claim 6, wherein, the conditions of the synthesis reaction include: the temperature is 165 - 175 °C; the time is 25 - 35 h.

8. The method according to claim 5, wherein, The dosages of the silicon source, aluminum source, first structure-directing agent, second structure-directing agent and water satisfy that Na 2 O:SiO 2 :Al 2 O 3 :the first structure-directing agent:the second structure-directing agent:H 2 O has a molar ratio of 0.28 - 0.4:1:0.01 - 0.02:0.02 - 0.22:0.02 - 0.12:20 - 40; and / or, the silicon source is water glass, and the molar ratio of SiO 2 and Na 2 in the water glass to O is 2 - 4:1; and / or, the aluminum source is selected from at least one of aluminum sulfate, aluminum nitrate and aluminum chloride; And / or, in the general formula of the first structure-directing agent, R 1 and R 2 are each independently methyl and / or ethyl, and X is selected from chlorine and / or bromine; And / or, in the general formula of the second structure-directing agent, R 3 is ethyl and / or propyl, and Y is selected from chlorine and / or bromine.

9. The method according to claim 8, wherein, The molar ratio of SiO 2 and Na 2 O in the sodium silicate is 2.5 - 3.5:

1.

10. A catalyst for isomerization reaction of xylene material containing ethylbenzene, characterized in that, the catalyst comprises a carrier and a metal component supported on the carrier; wherein, the carrier comprises a hydrogen-type eutectic molecular sieve and a binder; wherein, the hydrogen-type eutectic molecular sieve is obtained by hydrogenation treatment of the eutectic molecular sieve according to any one of claims 1 - 4.

11. The catalyst according to claim 10, wherein, based on the total weight of the catalyst, the content of the hydrogen-type eutectic molecular sieve is 20 - 90 wt%; the content of the binder is 9.94 - 75 wt%; the content of the metal component is 0.01 - 5 wt%; And / or, the molar content of Na 2 O in the hydrogen form of the eutectic molecular sieve is 0.01-2%.

12. The catalyst according to claim 11, wherein, based on the total weight of the catalyst, the content of the hydrogen-type eutectic molecular sieve is 50 - 80 wt%; the content of the binder is 19.95 - 49.75 wt%; the content of the metal component is 0.05 - 0.25 wt%; and / or, the molar content of Na 2 in the hydrogen form eutectic molecular sieve is 0.1 - 0.4%.

13. A method for preparing a catalyst for the isomerization reaction of xylene materials containing ethylbenzene, characterized in that, the method comprises the following steps: (I-a) subjecting the eutectic molecular sieve to first ion exchange, first washing, first drying, first calcination, and first shaping in sequence to obtain a support; or, (I-b) subjecting the eutectic molecular sieve to second shaping, second ion exchange, second washing, second drying, and second calcination in sequence to obtain a support; (II) impregnating the support in a soluble metal salt solution, and subjecting the obtained product to activation and reduction in sequence to obtain a catalyst; wherein, the eutectic molecular sieve is the eutectic molecular sieve described in any one of claims 1-4.

14. According to the method of claim 13, wherein, in step (I-a), the process of the first ion exchange comprises: performing the first ion exchange on the eutectic molecular sieve with an aqueous solution of a second structure-directing agent; wherein, the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the eutectic molecular sieve in g is 1-50:1; and / or, the process of the first washing comprises: washing the product of the first ion exchange with deionized water so that there are no halogen ions in the wash liquor and the pH of the wash liquor is 6-8; and / or, the molar content of Na 2 O in the product of the first washing is 0.01 - 2%; and / or, the process of the first shaping comprises: mixing the product of the first calcination with a binder and an acid solution, and extruding and shaping the obtained mixture; wherein, the weight ratio of the product of the first calcination, the binder, and the acid solution is 1:0.11-4:0.1-2.

15. According to the method of claim 14, wherein, in step (I-a), the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the eutectic molecular sieve in g is 5-30:1; and / or, the molar content of Na 2 O in the product of the first washing is 0.1 - 0.4%; and / or, the weight ratio of the product of the first calcination, the binder, and the acid solution is 1:0.25-1:0.3-1.

2.

16. According to the method of claim 14, wherein, in step (I-b), the process of the second shaping comprises: mixing the eutectic molecular sieve with a binder and an acid solution, and extruding and shaping the obtained mixture; wherein, the weight ratio of the eutectic molecular sieve, the binder, and the acid solution is 1:0.11-4:0.1-2; and / or, the process of the second ion exchange comprises: performing the second ion exchange on the product of the second shaping with an aqueous solution of a second structure-directing agent; wherein, the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the product of the second shaping in g is 1-50:1; and / or, the process of the second washing comprises: washing the product of the second ion exchange with deionized water so that there are no halogen ions in the wash liquor and the pH of the wash liquor is 6-8; and / or, the molar content of Na 2 O in the product of the second washing is 0.01 - 2%.

17. According to the method of claim 16, wherein, in step (I-b), the weight ratio of the eutectic molecular sieve, the binder, and the acid solution is 1:0.25-1:0.3-1.2; and / or, the dosage ratio of the aqueous solution of the second structure-directing agent in mL to the product of the second shaping in g is 5-30:1; and / or, the molar content of Na 2 O in the product of the second washing is 0.1 - 0.4%.

18. The method according to claim 16, wherein, in the aqueous solution of the second structure-directing agent, the concentration of the second structure-directing agent is 0.01 - 0.08 mol / L; and / or, the conditions of the first ion exchange and the second ion exchange each independently include: the temperature is 50 - 100 °C; the number of times is ≥ 1 time; and / or, the conditions of the first drying and the second drying each independently include: the temperature is 80 - 150 °C; the time is 1 - 24 h; and / or, the conditions of the first calcination and the second calcination each independently include: the temperature is 400 - 600 °C; the time is 1 - 24 h.

19. The method according to claim 18, wherein, in the aqueous solution of the second structure-directing agent, the concentration of the second structure-directing agent is 0.04 - 0.06 mol / L; and / or, the conditions of the first ion exchange and the second ion exchange each independently include: the temperature is 60 - 90 °C; the number of times is 2 - 4 times; and / or, the conditions of the first drying and the second drying each independently include: the temperature is 90 - 120 °C; the time is 5 - 20 h; and / or, the conditions of the first calcination and the second calcination each independently include: the temperature is 450 - 550 °C; the time is 5 - 15 h.

20. The method according to any one of claims 13 - 19, wherein, in step (II), in the soluble metal salt solution, the metal concentration in the soluble metal salt is 0.2 - 5 g / L; wherein, the soluble metal salt is hexachloroplatinate(IV) hydrochloride; and / or, the dosage ratio of the carrier in g to the soluble metal salt solution in mL is 1:1 - 5.

21. The method according to claim 20, wherein, in step (II), in the soluble metal salt solution, the metal concentration in the soluble metal salt is 0.5 - 3.5 g / L; and / or, the dosage ratio of the carrier in g to the soluble metal salt solution in mL is 1:1 - 2.

5.

22. A method for isomerization reaction of a xylene material containing ethylbenzene, characterized in that the method includes: in the presence of hydrogen, contacting a xylene material containing ethylbenzene with a catalyst and carrying out a reaction; wherein, the catalyst is the catalyst according to any one of claims 10 - 12, or the catalyst prepared by the method according to any one of claims 13 - 21.

23. The method according to claim 22, wherein, in the xylene containing ethylbenzene, the ethylbenzene content is 1 - 20 wt%.

24. The method according to claim 23, wherein, when the ethylbenzene content in the xylene material containing ethylbenzene is 1 - 10 wt%, the reaction is an ethylbenzene deethylation reaction; when the ethylbenzene content in the xylene material containing ethylbenzene is 10 - 20 wt%, the reaction is an ethylbenzene to xylene conversion reaction.

25. The method according to claim 24, wherein, The conditions for the ethylbenzene de-ethylation reaction include: temperature of 355 - 375 °C; pressure of 0.4 - 0.8 MPa; weight hourly space velocity of 6 - 10 h -1 ; hydrogen-hydrocarbon molar ratio of 0.8 - 1.5:1; And / or, the conditions for the ethylbenzene to xylene reaction include: temperature is 375 - 395 °C; pressure is 0.8 - 1.5 MPa; weight hourly space velocity is 3 - 6 h -1 ; hydrogen to hydrocarbon molar ratio is 2.5 - 3.5:1.

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