Oxygenate-to-aromatics catalysts, methods for making and using the same

Abstract

The present application relates to the field of catalyst, specifically relates to a kind of oxygen-containing compound preparation aromatic hydrocarbon catalyst and its preparation method and application, the catalyst contains 0.5-10 parts metal oxide by weight percentage;50-89 parts molecular sieve and 10-40 parts binder;The catalyst has the multi-level pore structure of micropore-mesopore-macropore;Wherein, the micropore with pore size size 0.3-2.0 nanometer accounts for 0.07-0.4 cubic centimeter / gram pore volume, 2-50 nanometer mesopore accounts for 0.12-2.2 cubic centimeter / gram pore volume, 0.05-1.0 micrometer macropore accounts for 0.2-3.5 cubic centimeter / gram pore volume.The catalyst of the present application can reduce the residence time of carbon deposition precursors in the micropore of molecular sieve through multi-level pore structure, significantly reduce the carbon deposition precursors in product, slow down carbon deposition, prolong the service life of catalyst.The preparation method of the present application can effectively control the ratio of micropore-mesopore-macropore of molecular sieve multi-level pore structure.The catalyst of the present application has the advantages of simple process, low wastewater, low carbon oxide compound when used in methanol to aromatic reaction.

Description

Technical Field

[0001] This invention relates to the field of catalysts, specifically to a catalyst for the production of aromatics from oxygen-containing compounds, its preparation method, and its applications. Background Technology

[0002] Aromatics, especially light aromatics (BTX, benzene, toluene, xylene), are important basic organic chemical raw materials, second only to ethylene and propylene in terms of production volume and scale. Downstream products of aromatics are widely used in the production of high-end and fine chemical products such as synthetic fibers, plastics, and rubber. In recent years, with the continuous development of related chemical industries, global demand for aromatics has continued to grow.

[0003] Currently, aromatics production mainly originates from catalytic reforming and gasoline extraction via the petroleum route, with a small amount from coal tar. Overseas, aromatics produced via the petroleum route account for over 98% of total production. In recent years, progress in aromatics technology research abroad has been slow, with investment primarily focused on China, a market with strong demand. The production of aromatics from oxygen-containing compounds is a new route for aromatics preparation, and this process is significant for alleviating aromatics resource shortages and extending the natural gas / coal chemical industry chain. Currently, the development of high-performance catalysts remains one of the most significant factors restricting the development of oxygen-containing compound-to-aromatics technology. Recently, researchers have discovered that bifunctional molecular sieves, with metal oxides and molecular sieves as their main components, are excellent catalysts for the production of aromatics from oxygen-containing compounds.

[0004] CN107010639A discloses a hierarchical porous ZSM-5 molecular sieve, its preparation method, and its application as an MTA catalyst. A mixture is prepared by sequentially mixing an alkali source, an aluminum source, an anionic surfactant, a dispersant, water, a silicon source, and ZSM-5 seed crystals, and then crystallizing the mixture at 140–180 °C. After drying, washing, and calcination, a hierarchical porous ZSM-5 molecular sieve with a high degree of dispersion and a hierarchical porous structure is obtained. The resulting hierarchical porous molecular sieve is then zinc-supported and shaped to prepare an MTA catalyst. The hierarchical porous structure improves the lifetime of the molecular sieve catalyst in the MTA reaction.

[0005] CN109607563A discloses a zinc-modified hierarchical porous ZSM-5 nanozeolite and its preparation method. The ZSM-5 nanozeolite has a hierarchical porous structure with zinc particles encapsulated within it. The preparation method involves mixing nano-ZSM-5 zeolite with an aqueous sodium hydroxide solution to obtain the hierarchical porous ZSM-5 nanozeolite. This is followed by ammonium exchange to impregnate the ZSM-5 nanozeolite with zinc, and then extruding it using silica sol, followed by dry gel conversion to obtain the zinc-modified hierarchical porous ZSM-5 nanozeolite. This zinc-modified hierarchical porous ZSM-5 nanozeolite, with zinc particles encapsulated within it, solves the problems of narrow pores, easy deactivation, and low aromatic selectivity associated with traditional zinc-modified ZSM-5 zeolite in methanol-to-aromatics reactions.

[0006] The literature reports above on catalysts and preparation methods for the production of aromatics from oxygen-containing compounds all have problems such as complex preparation processes, large amounts of wastewater, and high levels of carbon and oxygen compounds in the products. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems of complex preparation processes, large wastewater volumes, and high oxygen content in existing technologies for the production of aromatics from oxygen-containing compounds. This invention provides a catalyst for the production of aromatics from oxygen-containing compounds, its preparation method, and its applications. When used in the methanol-to-aromatics reaction, this catalyst offers advantages such as simple preparation processes, low wastewater volumes, and low carbon and oxygen content in the products.

[0008] To achieve the above objectives, the first aspect of the present invention provides a catalyst for the production of aromatics from oxygen-containing compounds, the catalyst comprising, by weight percentage, 0.5-10 parts of metal oxide; 50-89 parts of molecular sieve and 10-40 parts of binder; the catalyst having a hierarchical pore structure of micropores-mesopores-macropores; wherein the pore volume occupied by micropores with a pore size of 0.3-2.0 nanometers is 0.07-0.4 cubic centimeters / gram, the pore volume occupied by mesopores with a pore size of 2-50 nanometers is 0.12-2.2 cubic centimeters / gram, and the pore volume occupied by macropores with a pore size of 0.05-1.0 micrometers is 0.2-3.5 cubic centimeters / gram.

[0009] The catalyst of this invention possesses a hierarchical pore structure of micropores, mesopores, and macropores. A hierarchical pore structure refers to the formation of more mesopores and macropores within a conventional molecular sieve structure through in-situ or post-processing. The inventors discovered that, due to the limitation of micropore size in molecular sieve catalysts, the production of aromatics from oxygen-containing compounds suffers from prominent problems such as rapid catalyst coking and deactivation. The catalyst of this invention, through its hierarchical pore structure, can reduce the residence time of coking precursors in the molecular sieve micropores, significantly reducing the amount of coking precursors in the product, slowing down coking, and extending the catalyst's lifespan.

[0010] A second aspect of the present invention provides a method for preparing the catalyst described herein, the method comprising:

[0011] a) After mixing the metal oxide precursor, silicon source, aluminum source, template agent and water evenly, dry to obtain precursor A with a water content of not more than 30% by weight.

[0012] b) Then, precursor A is subjected to aging treatment to obtain precursor B;

[0013] c) Calcine precursor B to obtain a metal oxide / molecular sieve composite.

[0014] d) Mix the metal oxide / molecular sieve composite with a binder, then shape, dry, and calcine.

[0015] The catalyst preparation method of this invention can effectively control the proportion of micropores, mesopores, and macropores in the hierarchical pore structure of molecular sieves. In the catalyst preparation method of this invention, the molecular sieve crystallization process employs an in-situ crystallization method with pre-added metal oxides, avoiding the cumbersome steps and secondary calcination, as well as the problems of element aggregation and unevenness, associated with methods such as impregnation. This method has the advantages of simple process and uniform element distribution. This method significantly reduces the formation of carbon oxides in the reaction of oxygen-containing compounds to aromatics, thereby improving the overall yield of aromatics.

[0016] The catalyst of this invention strictly controls the amount of water used during the molecular sieve crystallization process, so that the crystallized system is in a semi-solid state with only surface liquid phase, which can effectively reduce the overall water consumption and wastewater generation.

[0017] A third aspect of the present invention provides the application of the catalyst described herein in the production of aromatics from oxygen-containing compounds.

[0018] The catalyst of this invention has the advantages of simple preparation process, low wastewater volume and low carbon and oxygen content in the product when used in the reaction of oxygen-containing compounds to produce aromatics.

[0019] The catalyst of this invention has good stability and high activity. When applied to the preparation of aromatics from oxygen-containing compounds, it has a long single-pass cycle, high selectivity for aromatics, and low carbon and oxygen content in the product. Detailed Implementation

[0020] 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.

[0021] This invention provides a catalyst for the production of aromatics from oxygen-containing compounds. The catalyst contains, by weight percentage, 0.5-10 parts of metal oxide, 50-89 parts of molecular sieve, and 10-40 parts of binder. The catalyst has a hierarchical pore structure of micropores-mesopores-macropores; wherein the pore volume occupied by micropores with a pore size of 0.3-2.0 nm is 0.07-0.4 cubic centimeters / g, the pore volume occupied by mesopores with a pore size of 2-50 nm is 0.12-2.2 cubic centimeters / g, and the pore volume occupied by macropores with a pore size of 0.05-1.0 μm is 0.2-3.5 cubic centimeters / g. The catalyst of this invention exhibits good stability and high activity. When applied to the production of aromatics from oxygen-containing compounds, it demonstrates a long single-pass cycle, high selectivity for aromatics, and low carbon and oxygen content in the product.

[0022] According to a particularly preferred embodiment of the present invention, the catalyst comprises micropores with a pore size of 0.3-2.0 nm occupying a pore volume of 0.1-0.36 cubic centimeters / gram, mesopores with a pore size of 2-50 nm occupying a pore volume of 0.15-2.0 cubic centimeters / gram, and macropores with a pore size of 0.05-1.0 μm occupying a pore volume of 0.25-2.5 cubic centimeters / gram.

[0023] According to a particularly preferred embodiment of the present invention, the specific surface area of ​​the catalyst is 150-350 square meters / gram.

[0024] According to a particularly preferred embodiment of the present invention, the molecular sieve is selected from any one or a mixture of two or more molecular sieves containing ten-membered ring channels, preferably one or more of ZSM-5, MCM-22, and ZSM-11 silica-alumina molecular sieves. By adopting the aforementioned preferred embodiment, the selectivity of aromatic hydrocarbons in the product and the operating cycle can be improved.

[0025] According to a particularly preferred embodiment of the present invention, the metal oxide is selected from any one or a mixture of two of zinc oxide, gallium oxide, molybdenum oxide, and manganese oxide. By employing the aforementioned preferred embodiment, the selectivity of the product aromatics and the operating cycle can be improved.

[0026] In this invention, the binder can be any conventional choice in the art, as long as it achieves the objective of the invention. According to a preferred embodiment of the invention, the binder is selected from at least one of alumina, silicon dioxide, titanium dioxide, and zirconium oxide. By employing the aforementioned preferred embodiment, the selectivity of the product aromatics and the operating cycle can be improved.

[0027] Literature reports on catalysts for the production of aromatics from oxygen-containing compounds highlight several issues. Due to the limited pore size of molecular sieve catalysts, these processes often suffer from short single-pass cycles and high levels of carbon and oxygen compounds in the products. The catalyst of this invention, through its hierarchical porous structure, reduces the residence time of carbon deposit precursors within the molecular sieve micropores, significantly decreasing the amount of carbon deposit precursors in the products, slowing down carbon deposition, and extending the catalyst's lifespan.

[0028] Catalysts possessing the aforementioned characteristics of this invention can all achieve the objectives of this invention, and there are no special requirements for their preparation methods. A second aspect of this invention provides a method for preparing the catalyst described in this invention, the method comprising:

[0029] a) After mixing the metal oxide precursor, silicon source, aluminum source, template agent and water evenly, dry to obtain precursor A with a water content of not more than 30% by weight.

[0030] b) Then, precursor A is subjected to aging treatment to obtain precursor B;

[0031] c) Calcine precursor B to obtain a metal oxide / molecular sieve composite.

[0032] d) Mix the metal oxide / molecular sieve composite with a binder, then shape, dry, and calcine.

[0033] According to a particularly preferred embodiment of the present invention, in the preparation method, in step a), the water content of precursor A is 1.5-14% by weight. Using the aforementioned preferred embodiment, the single-pass operating cycle of the catalyst can be effectively extended and the selectivity of aromatics can be improved.

[0034] According to a particularly preferred embodiment of the present invention, in the preparation method, in step a), the metal oxide precursor is calculated as a metal, the silicon source as silicon atoms, the aluminum source as aluminum atoms, and the mixture, in molar quantities, has a ratio of metal:silicon:aluminum:template agent:water = (0.004-0.15):1:(0.01-0.15):(0.04-1.2):(0.5-10). Using the aforementioned preferred embodiment, the catalyst's single-pass operating cycle can be effectively extended and the aromatic selectivity improved.

[0035] In this invention, the drying conditions in step a) can be conventional choices in the art. According to a particularly preferred embodiment of the invention, the drying conditions in step a) include: a temperature of 50-120°C and a time of 2-50 hours. By adopting the aforementioned preferred scheme, the water content in precursor A can be controlled, thereby controlling the proportion of different pores, extending the single-pass operating cycle of the catalyst, and improving the selectivity of aromatics.

[0036] In this invention, the aging conditions in step b) can be conventionally chosen in the art. According to a particularly preferred embodiment of the invention, the aging conditions in step b) include: a temperature of 120-200°C and a time of 2-50 hours. By adopting the aforementioned preferred scheme, the proportion of different pores can be controlled, extending the catalyst's single-pass operating cycle and improving aromatic selectivity.

[0037] To further extend the single-pass operating cycle of the catalyst and improve the selectivity of aromatics, according to a preferred embodiment of the present invention, in step b), the aging treatment conditions include: a temperature of 150-170°C and a time of 32-48 hours.

[0038] In this invention, in order to further extend the single-pass operating cycle of the catalyst, according to a preferred embodiment of the invention, the aging treatment conditions in step b) include: a temperature of 150-170°C and a time of 2-50 hours, preferably 32-48 hours.

[0039] In this invention, the calcination conditions in step c) can be conventionally chosen in the art. According to a particularly preferred embodiment of the invention, the calcination conditions in step c) include: a temperature of 400-800°C and a time of 3-10 hours. By adopting the aforementioned preferred embodiment, the proportion of different pore types can be controlled, extending the catalyst's single-pass operating cycle and improving aromatic selectivity.

[0040] In this invention, the drying conditions in step d) can be conventionally chosen in the art. According to a particularly preferred embodiment of the invention, the drying conditions in step d) include: a temperature of 60-200°C and a time of 4-25 hours. By adopting the aforementioned preferred embodiment, the proportion of different pores can be controlled, the single-pass operating cycle of the catalyst can be extended, and the selectivity of aromatics can be improved.

[0041] In this invention, the calcination conditions in step d) can be conventionally chosen in the art. According to a particularly preferred embodiment of the invention, the calcination conditions in step d) include: a temperature of 400-750°C and a time of 3-48 hours. By adopting the aforementioned preferred embodiment, the proportion of different pore types can be controlled, extending the catalyst's single-pass operating cycle and improving aromatic selectivity.

[0042] According to a particularly preferred embodiment of the present invention, in the preparation method, the metal oxide precursor can be selected from a wide range, and for the present invention, it is preferably selected from at least one of nitrates, carbonates, phosphates, acetates and fatty alcohol esters.

[0043] According to a particularly preferred embodiment of the present invention, in the preparation method, the silicon source can be selected from a wide range of types. For the present invention, it is preferably selected from at least one of fatty alcohol silicates, silicates, silica sols and water glass.

[0044] According to a particularly preferred embodiment of the present invention, in the preparation method, the range of aluminum sources is relatively wide. For the present invention, it is preferably selected from at least one of aluminum nitrate, aluminum sulfate, aluminum chloride, aluminum fatty alcohol, aluminate, hydrated alumina and alumina.

[0045] According to a particularly preferred embodiment of the present invention, in the preparation method, the type of template agent can be selected from a wide range. For the present invention, it is preferably selected from at least one of sodium hydroxide, potassium hydroxide, ammonia, ethylenediamine, triethylamine and aliphatic ammonium hydroxide.

[0046] According to a particularly preferred embodiment of the present invention, in the preparation method, the type of binder can be selected from a wide range, and for the present invention, it is preferably selected from one or more of alumina, silicon oxide, titanium oxide, and zirconium oxide.

[0047] By adopting the aforementioned preferred embodiments, the proportion of different pores can be adjusted, thereby extending the single-pass operation cycle of the catalyst.

[0048] A third aspect of the present invention provides the application of the catalyst described herein in the production of aromatics from oxygen-containing compounds.

[0049] The catalyst of this invention is used in the catalytic production of aromatics from dimethyl ether. When the zinc oxide content in the catalyst is 2.5 parts by weight, the reaction temperature is 430°C, the reaction pressure is 0.25 MPa, and the dimethyl ether weight hourly space velocity is 0.6 h⁻¹. -1 Under the specified conditions, when the catalyst is reacted with dimethyl ether, the initial conversion rate of dimethyl ether is 99.6%, the content of carbon oxides in the product is only 1.9%, and the single-pass operation cycle of the catalyst can reach 220 hours (based on a conversion rate greater than 90%). In contrast, a catalyst prepared by impregnating a molecular sieve using a conventional hydrothermal crystallization method with a metal oxide precursor achieves an initial conversion rate of dimethyl ether of 99.5%, a content of carbon oxides in the product of 2.8%, and a single-pass operation cycle of only 160 hours (based on a conversion rate greater than 90%). Compared to the latter, the catalyst of this invention reduces the content of carbon oxides in the product of the dimethyl ether to aromatics process by 46.4%, and increases the single-pass operation cycle by 37.5%, achieving better technical results.

[0050] The technical solution of the present invention will be further described below through embodiments, but the scope of protection of the present invention is not limited to the embodiments. All catalysts used in all embodiments and comparative examples of the present invention employ the same evaluation procedures and methods.

[0051] The catalyst was evaluated under the following conditions: using 30 wt% dimethyl ether + 30 wt% methanol + 40 wt% water as the starting material, the reaction temperature was 430℃, and the feed weight hourly space velocity (WHSV) was 0.6 h⁻¹. -1 The pressure is 0.25 MPa.

[0052] In this invention, the measured moisture content refers to the percentage decrease in weight before and after drying at 100°C for 4 hours.

[0053] A single-cycle operation refers to the total stable operating time when the conversion rate of oxygen-containing compound feedstock is higher than 95%.

[0054] The contents of metal oxides, molecular sieves, and binders were determined using X-ray fluorescence.

[0055] The pore distribution was determined by nitrogen adsorption and fitted using the Barrett-Joyner-Halenda method.

[0056] Example 1

[0057] a) Add 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide to 70 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio is 0.016:1.0:0.015:0.2:8.5), stir until homogeneous to form a homogeneous mixture, and then dry at 80 degrees for 5 hours to obtain solid precursor A. The water content of precursor A is 4% by weight.

[0058] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0059] c) Precursor B was calcined at 500℃ for 8 hours to obtain a zinc oxide / molecular sieve composite.

[0060] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0061] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, 87.2% ZSM-5 molecular sieve by weight, and 11.7% binder by weight. The catalyst has a specific surface area of ​​318 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.35 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 1.1 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.35 cm³ / g.

[0062] The initial conversion rate of the reactants was 99.7%, the content of carbon oxides in the product was 1.4%, and the catalyst's single-pass operation cycle could reach 260 hours.

[0063] Example 2

[0064] a) 17.50 g of anhydrous gallium acetate, 100 g of tetraethyl silicate, 13 g of aluminum isopropoxide and 56 g of hexamethyleneimine were added to 8 g of water to prepare a mixture (gallium:silicon:aluminum:template:water molar ratio of 0.15:1.0:0.14:0.86:0.9). The mixture was stirred until homogeneous and then dried at 110 degrees for 17 hours to obtain solid precursor A. The water content of precursor A was 1.6% by weight.

[0065] b) The precursor A was then aged at 170°C for 40 hours to obtain a solid composite (precursor B).

[0066] c) Precursor B was calcined at 600℃ for 6 hours to obtain gallium oxide / molecular sieve composite.

[0067] d) Subsequently, the above gallium oxide / molecular sieve composite was mixed with 105 g of aluminum sol (alumina content of 20%), extruded, dried, and calcined. The drying temperature was 65°C and the drying time was 22 hours. The calcination temperature was 600°C and the calcination time was 15 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0068] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 9.8% gallium oxide by weight, 55.7% MCM-22 molecular sieve by weight, and 34.5% binder by weight. The catalyst has a specific surface area of ​​167 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.12 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.21 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 2.3 cm³ / g.

[0069] The initial conversion rate of the reactants was 99.7%, the content of carbon oxides in the product was 2.4%, and the single-pass operation cycle of the catalyst could reach 255 hours.

[0070] Example 3

[0071] a) Add 5.8 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 3.3 g of aluminum isopropoxide and 12 g of tetrabutylammonium hydroxide to 40 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio is 0.07:1.0:0.04:0.08:4.0), stir until homogeneous to form a homogeneous mixture, and then dry at 53 degrees for 46 hours to obtain solid precursor A. The water content of precursor A is 13.5% by weight.

[0072] b) The precursor A was then aged at 150°C for 48 hours to obtain a solid composite (precursor B).

[0073] c) Precursor B was calcined at 720°C for 3 hours to obtain a zinc oxide / molecular sieve composite.

[0074] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 66 g of titanium sol (titanium oxide content of 20%), extruded, dried, and calcined. The drying temperature was 190°C and the drying time was 5 hours. The calcination temperature was 730°C and the calcination time was 4 hours, thus obtaining the catalyst for the production of aromatics from the oxygen-containing compound.

[0075] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 4.4% zinc oxide by weight, 70.7% ZSM-11 molecular sieve by weight, and 24.9% binder by weight. The catalyst has a specific surface area of ​​239 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.23 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 1.0 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 1.5 cm³ / g.

[0076] The initial conversion rate of the reactants was 99.7%, the content of carbon oxides in the product was 1.6%, and the single-pass operation cycle of the catalyst could reach 255 hours.

[0077] Example 4

[0078] Follow the steps in Example 1, only changing the type of molecular sieve obtained.

[0079] a) 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide, 19 g of 1-ethylpyridine bromide, and 4 g of sodium hydroxide were added to 70 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio of 0.016:1.0:0.015:0.2:8.1). The mixture was stirred until homogeneous and then dried at 80 degrees Celsius for 5 hours to obtain solid precursor A. The water content of precursor A was 4% by weight.

[0080] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0081] c) Precursor B was calcined at 500℃ for 8 hours to obtain a zinc oxide / molecular sieve composite.

[0082] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0083] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, ZSM-22 molecular sieve with a weight percentage of 87.4%, and a binder with a weight percentage of 11.5%. The catalyst has a specific surface area of ​​321 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.32 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 1.1 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.33 cm³ / g.

[0084] The initial conversion rate of the reactants was 88.4%, the content of carbon oxides in the products was 1.4%, and the single-pass operation cycle of the catalyst was 210 hours.

[0085] Example 5

[0086] The steps in Example 1 are followed, except that the type of metal oxide is changed.

[0087] a) 1.40 g of anhydrous manganese acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide were added to 70 g of water to prepare a mixture (manganese:silicon:aluminum:template:water molar ratio of 0.016:1.0:0.015:0.2:8.1). The mixture was stirred until homogeneous and then dried at 80 degrees for 5 hours to obtain solid precursor A. The water content of precursor A was 3.8% by weight.

[0088] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0089] c) Precursor B was calcined at 500℃ for 8 hours to obtain manganese oxide / molecular sieve composite.

[0090] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0091] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% manganese oxide by weight, 87.2% ZSM-5 molecular sieve by weight, and 11.7% binder by weight. The catalyst has a specific surface area of ​​318 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.35 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 1.1 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.35 cm³ / g.

[0092] The initial conversion rate of the reactants was 98.7%, the content of carbon oxides in the product was 1.9%, and the single-pass operation cycle of the catalyst could reach 215 hours.

[0093] Example 6

[0094] The steps in Example 1 were followed, except that the drying conditions and the moisture content of precursor A in step a) were changed.

[0095] a) 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide were added to 70 g of water to prepare a mixture (the molar ratio of zinc:silicon:aluminum:template:water was 0.016:1.0:0.015:0.2:8.1). The mixture was stirred until homogeneous and then dried at 45 degrees for 1.5 hours to obtain solid precursor A. The water content of precursor A was 28.7% by weight.

[0096] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0097] c) Precursor B was calcined at 500℃ for 8 hours to obtain a zinc oxide / molecular sieve composite.

[0098] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0099] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, 87% ZSM-5 molecular sieve by weight, and 11.9% binder by weight. The catalyst has a specific surface area of ​​238 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.15 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.13 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.35 cm³ / g.

[0100] The initial conversion rate of the reactants was 99.7%, the content of carbon oxides in the product was 1.4%, and the single-pass operation cycle of the catalyst was 195 hours.

[0101] Example 7

[0102] Following the steps in Example 1, only the aging conditions in step b) are changed.

[0103] a) Add 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide to 70 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio is 0.016:1.0:0.015:0.2:8.5), stir evenly to form a homogeneous mixture, and then dry at 80 degrees for 5 hours to obtain solid precursor A. The water content of precursor A is 4% by weight.

[0104] b) The precursor A was then aged at 130°C for 4 hours to obtain a solid composite (precursor B).

[0105] c) Precursor B was calcined at 500℃ for 8 hours to obtain a zinc oxide / molecular sieve composite.

[0106] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0107] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, 87.1% ZSM-5 molecular sieve by weight, and 11.8% binder by weight. The catalyst has a specific surface area of ​​418 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.08 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 1.5 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.55 cm³ / g.

[0108] The initial conversion rate of the reactants was 94.3%, the content of carbon oxides in the products was 2.4%, and the catalyst had a single-pass operating cycle of 200 hours.

[0109] Example 8

[0110] Following the steps in Example 1, the drying and calcination conditions in steps c) and d) were changed.

[0111] a) Add 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide to 70 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio is 0.016:1.0:0.015:0.2:8.5), stir evenly to form a homogeneous mixture, and then dry at 80 degrees for 5 hours to obtain solid precursor A. The water content of precursor A is 4% by weight.

[0112] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0113] c) Precursor B was calcined at 350°C for 2 hours to obtain a zinc oxide / molecular sieve composite.

[0114] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 210°C and the drying time was 30 hours. The calcination temperature was 350°C and the calcination time was 2 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0115] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.2% zinc oxide by weight, 87.3% ZSM-5 molecular sieve by weight, and 11.5% binder by weight. The catalyst has a specific surface area of ​​246 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.22 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.15 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.26 cm³ / g.

[0116] The initial conversion rate of the reactants was 99.4%, the content of carbon oxides in the product was 1.4%, and the single-pass operation cycle of the catalyst was 200 hours.

[0117] Comparative Example 1

[0118] The main difference from Example 1 is that the molecular sieve is prepared first, and then the metal oxide is loaded, specifically:

[0119] a) Add 100g of tetraethyl silicate, 1.5g of aluminum isopropoxide and 20g of tetrapropylammonium hydroxide to 70g of water to prepare a mixture (silicon source: aluminum source: template agent: water ratio is 1.0:0.015:0.2:8.1), stir evenly to form a homogeneous mixture, and then dry at 80 degrees for 5 hours to obtain precursor A. The water content of precursor A is 4.1% by weight.

[0120] b) The precursor A was then aged at 160°C for 40 hours to obtain the solid composite precursor B.

[0121] c) Precursor B was calcined at 500°C for 8 hours to obtain a molecular sieve composite.

[0122] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the shaped molecular sieve.

[0123] e) Dissolve 1.5 g of anhydrous zinc acetate in 10 g of water, load the zinc acetate solution onto a molded molecular sieve carrier by impregnation, and then dry and calcine to obtain the catalyst for the production of aromatics from oxygen-containing compounds in Comparative Example 1.

[0124] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, 87.0% molecular sieve by weight, and 11.9% binder by weight. The catalyst has a specific surface area of ​​118 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.06 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.11 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.20 cm³ / g.

[0125] The initial conversion rate of the reactants was 99.1%, the content of carbon oxides in the product was 12.5%, and the single-pass operation cycle of the catalyst was 125 hours.

[0126] Compared with Example 1, it can be seen that the pore volume of the catalyst obtained by the impregnation method is significantly reduced. In Comparative Example 1, the micropore volume with a pore size of 0.3-2.0 nm is 17% remaining, the mesopore volume with a pore size of 2-50 nm is 10% remaining, and the macropore volume with a pore size of 0.05-1.0 μm is 57% remaining. The carbon oxide content in the product is significantly increased to 8.9 times that of Example 1, and the single-pass operation cycle is shortened to 48% of that of Example 1.

[0127] Comparative Example 2

[0128] Except for the molecular sieve preparation process, which uses the traditional hydrothermal crystallization method, all other procedures were carried out in accordance with Example 1, specifically as follows:

[0129] a) Add 1.50 g of zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide to 70 g of water to prepare a mixture (zinc source: silicon source: aluminum source: template agent: water ratio is 0.016:1.0:0.015:0.2:8.1), stir evenly to form a homogeneous mixture, and then treat it in a sealed environment at 80 degrees for 5 hours to obtain mixture A). By weight, mixture A has a water content of 37%.

[0130] b) The mixture A was then crystallized in a crystallization vessel for 40 hours at a crystallization temperature of 160°C, and filtered to obtain solid phase B.

[0131] c) Solid phase B was calcined at 500℃ for 8 hours to obtain zinc oxide / molecular sieve composite.

[0132] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0133] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 0.9% zinc oxide by weight, 86.6% molecular sieve by weight, and 12.5% ​​binder by weight. The catalyst has a specific surface area of ​​268 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.21 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.08 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.18 cm³ / g.

[0134] The initial conversion rate of the reactants was 99.6%, the content of carbon oxides in the product was 1.2%, and the single-pass operation cycle of the catalyst was 110 hours.

[0135] Compared with Example 1, it can be seen that Comparative Example 2 adopted the traditional hydrothermal crystallization step. Even though the metal oxide was supported in situ, the pore volume of the catalyst was still severely reduced. In Comparative Example 1, the micropore volume with a pore size of 0.3-2.0 nm remained at 59%, the mesopore volume with a pore size of 2-50 nm remained at 8%, and the macropore volume with a pore size of 0.05-1.0 μm remained at 51%. The single-pass operation cycle of Comparative Example 2 was significantly shorter than that of Example 1, only 43% of the latter.

[0136] Comparative Example 3

[0137] Except for changing the drying step in step a) to adjust the moisture content of precursor A, the rest is carried out in accordance with Example 1, specifically as follows:

[0138] a) Add 1.50 g of anhydrous zinc acetate, 100 g of tetraethyl silicate, 1.5 g of aluminum isopropoxide and 20 g of tetrapropylammonium hydroxide to 70 g of water to prepare a mixture (zinc:silicon:aluminum:template:water molar ratio is 0.016:1.0:0.015:0.2:8.5), stir evenly to form a homogeneous mixture, and then dry at 30 degrees for 2 hours to obtain solid precursor A. By weight, precursor A has a water content of 37%.

[0139] b) The precursor A was then aged at 160°C for 32 hours to obtain a solid composite (precursor B).

[0140] c) Precursor B was calcined at 500℃ for 8 hours to obtain a zinc oxide / molecular sieve composite.

[0141] d) Subsequently, the above zinc oxide / molecular sieve composite was mixed with 15 g of silica sol (silica content of 40%), extruded, dried, and calcined. The drying temperature was 100°C and the drying time was 10 hours. The calcination temperature was 480°C and the calcination time was 40 hours to obtain the catalyst for the production of aromatics from the oxygen-containing compound.

[0142] The obtained catalyst for the production of aromatics from oxygen-containing compounds contains 1.1% zinc oxide by weight, 87.2% ZSM-5 molecular sieve by weight, and 11.7% binder by weight. The catalyst has a specific surface area of ​​318 m² / g. Specifically, micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.25 cm³ / g, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.12 cm³ / g, and macropores with a pore size of 0.05-1.0 μm occupy a pore volume of 0.14 cm³ / g.

[0143] The initial conversion rate of the reactants was 99.7%, the content of carbon oxides in the product was 3.9%, and the single-pass operation cycle of the catalyst could reach 135 hours.

[0144] Compared with Example 1, it can be seen that Comparative Example 3 adopted a different drying condition in step a), which affected the water content in precursor A. The resulting catalyst pore volume was significantly reduced. In Comparative Example 1, the micropore volume with a pore size of 0.3-2.0 nm remained at 71%, the mesopore volume with a pore size of 2-50 nm remained at 11%, and the macropore volume with a pore size of 0.05-1.0 μm remained at 40%. The single-pass operation cycle of Comparative Example 3 was significantly shorter than that of Example 1, only 52% of the latter.

[0145] 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 specific technical features in any 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. A catalyst for the production of aromatics from oxygen-containing compounds, characterized in that, The catalyst contains, by weight percentage, 0.5-10 parts of metal oxide, 50-89 parts of molecular sieve, and 10-40 parts of binder; the catalyst has a hierarchical pore structure of micropores-mesopores-macropores; wherein the pore volume occupied by micropores with a pore size of 0.3-2.0 nm is 0.07-0.4 cubic centimeters / gram, the pore volume occupied by mesopores with a pore size of 2-50 nm is 0.12-2.2 cubic centimeters / gram, and the pore volume occupied by macropores with a pore size of 0.05-1.0 μm is 0.2-3.5 cubic centimeters / gram.

2. The catalyst according to claim 1, wherein, Micropores with a pore size of 0.3-2.0 nm occupy a pore volume of 0.1-0.36 cubic centimeters / gram, mesopores with a pore size of 2-50 nm occupy a pore volume of 0.15-2.0 cubic centimeters / gram, and macropores with a pore size of 0.05-1.0 micrometers occupy a pore volume of 0.25-2.5 cubic centimeters / gram; and / or The specific surface area of ​​the catalyst is 150-350 square meters per gram.

3. The catalyst according to claim 1 or 2, wherein, The molecular sieve is selected from one or more molecular sieves containing ten-membered ring channels; and / or The metal oxide is selected from one or more of zinc oxide, gallium oxide, molybdenum oxide, and manganese oxide; and / or The binder is selected from at least one of alumina, silicon dioxide, titanium dioxide, and zirconium oxide.

4. The catalyst according to claim 1 or 2, wherein, The molecular sieves are selected from one or more of ZSM-5, MCM-22, and ZSM-11 silica-alumina molecular sieves; and / or The metal oxide is selected from zinc oxide and / or gallium oxide.

5. A method for preparing the catalyst according to any one of claims 1-4, characterized in that, The method includes: a) After mixing the metal oxide precursor, silicon source, aluminum source, template agent and water evenly, dry to obtain precursor A with a water content of not more than 30% by weight. b) Then, precursor A is subjected to aging treatment to obtain precursor B; c) Calcine precursor B to obtain a metal oxide / molecular sieve composite. d) Mix the metal oxide / molecular sieve composite with a binder, then shape, dry, and calcine.

6. The preparation method according to claim 5, wherein, In step a), The water content of precursor A is 1.5-14% by weight; and / or Drying conditions include: a temperature of 50-120℃ and a time of 2-50 hours; and / or The metal oxide precursor is calculated as metal, the silicon source as silicon atoms, the aluminum source as aluminum atoms, and the mixture is calculated as moles. The ratio of metal:silicon:aluminum:template agent:water is (0.004-0.15):1:(0.01-0.15):(0.04-1.2):(0.5-10).

7. The preparation method according to claim 5 or 6, wherein, In step b), the aging treatment conditions include a temperature of 120-200℃.

8. The preparation method according to claim 7, wherein, In step b), the aging treatment conditions include: a temperature of 150-170℃ and a time of 2-50 hours.

9. The preparation method according to claim 8, wherein, In step b), the aging treatment conditions include a time of 32-48 hours.

10. The preparation method according to claim 5 or 6, wherein, Step c), the calcination conditions include: a temperature of 400-800℃ and a time of 3-10 hours.

11. The preparation method according to claim 5 or 6, wherein, In step d), Drying conditions include: a temperature of 60-200℃ and a time of 4-25 hours; and / or The roasting conditions include a temperature of 400-750℃ and a time of 3-48 hours.

12. The preparation method according to claim 5 or 6, wherein, The metal oxide precursor is selected from at least one of nitrates, carbonates, phosphates, acetates, and fatty alcohol esters; and / or The silicon source is selected from at least one of fatty alcohol silicate, silicate, silica sol and water glass; The aluminum source is selected from at least one of aluminum nitrate, aluminum sulfate, aluminum chloride, aluminum fatty alcohol, aluminate, hydrated alumina, and alumina; and / or The template agent is selected from at least one of sodium hydroxide, potassium hydroxide, ammonia, ethylenediamine, triethylamine, and aliphatic ammonium hydroxide; and / or The binder is selected from one or more of alumina, silicon dioxide, titanium dioxide, and zirconium oxide.

13. The use of the catalyst according to any one of claims 1-4 in the production of aromatics from oxygen-containing compounds.