Silicon-aluminum zeolite SCM-36, method of manufacturing the same, and application

Abstract

A silicon-aluminum zeolite SCM-36 having a silicon / aluminum ratio n ≥ 5 and a distinct XRD diffraction spectrum, a method for manufacturing the same, and applications are provided. The SCM-36 zeolite is a novel zeolite that can be used as an adsorbent, a catalyst, or a catalyst carrier.

Description

Technology Field

[0001] This application relates to the field of zeolite technology, and in particular to silicon-aluminum zeolite, a method for manufacturing the same, and uses thereof. Background Technology

[0002] In industry, zeolite materials are widely used in fields such as catalysis, ion exchange, adsorption, and separation due to their hollow structures and large surface areas. Structural subtle differences in these materials result in variations in various observable properties used to characterize them, such as their morphology, specific surface area, pore size, and variability of pore size. On the other hand, these differences also imply significant variations in the catalytic and adsorption properties of the materials themselves.

[0003] The basic framework structure of crystalline microporous zeolites is based on a rigid three-dimensional TO4 (SiO4, AlO4, etc.) unit structure; in this structure, TO4 shares oxygen atoms in a tetrahedral manner, and the charge balance of the framework tetrahedra, such as AlO4, is Na + and H + It is maintained through the presence of surface cations such as [mentioning missing]. Therefore, it is clear that the skeletal properties of zeolites can be modified through cation exchange. At the same time, the zeolite structure contains an abundant pore channel system with a specific pore size. These pore channels intertwine to form a three-dimensional network structure, allowing the skeleton to remain stable even after water or organic matter within the pores is removed (US 4439409). Based on the above structure, zeolites not only exhibit excellent catalytic activity and conformation selectivity for various organic reactions, but also achieve good selectivity through modification (US 6162416, US 4954325, US 5362697).

[0004] The specific structure of a zeolite is determined by X-ray diffraction (XRD) spectra measured using an X-ray powder diffractometer with a Cu-K α X-ray source and a nickel filter. Different zeolites have different XRD spectral characteristics. All known zeolites, such as Type A zeolites, Type Y zeolites, and MCM-22 zeolites, have XRD spectra with unique characteristics.

[0005] Meanwhile, zeolites that have the same XRD spectral characteristics but different types of skeletal elements are different zeolites. For example, TS-1 zeolite (US4410501) and ZSM-5 zeolite (US3702886) have the same XRD spectral characteristics but different skeletal elements. Specifically, the skeletal elements of TS-1 zeolite are Si and Ti, which have catalytic oxidation functions, whereas the skeletal elements of ZSM-5 zeolite are Si and Al, which have acid catalytic functions.

[0006] In addition, zeolites that have the same XRD spectral characteristics and the same types of skeletal elements but different relative contents of skeletal elements are also different zeolites. For example, X zeolite (US2882244) and Y zeolite (US3130007) have the same XRD spectral characteristics and the same skeletal elements, Si and Al, but different relative contents of Si / Al. Specifically, the Si / Al molar ratio of X zeolite is less than 1.5, whereas the Si / Al molar ratio of Y zeolite is greater than 1.5.

[0007] The object of the present application is to provide a novel silicon-aluminum zeolite (referred to as SCM-36 zeolite in this application), a method for manufacturing the same, and uses thereof. The zeolite has specific XRD spectral characteristics and can be used as an adsorbent, a catalyst support, and a catalyst. When used as a catalyst in the reaction of 2,5-dimethylfuran and / or 2,5-hexanedion for the production of p-xylene, it exhibits high selectivity for p-xylene and high cyclic stability.

[0008] To achieve the above objective, in one aspect, the present application provides a silicon-aluminum zeolite having a silicon / aluminum ratio n such that n≥5, and the X-ray diffraction spectrum of the zeolite exhibits the relative intensity characteristics of the diffraction peaks shown in the following table:

[0009] .

[0010] In another aspect, the present application provides a method for manufacturing a silicon-aluminum zeolite comprising the following steps:

[0011] 1) a step of obtaining a zeolite by crystallizing a mixture comprising a silicon source, an aluminum source, an organic structure directing agent (A), an organic structure directing agent (B), an alkali source, and water; and

[0012] 2) Optionally, a step of calcining the zeolite obtained in step 1);

[0013] Here, the organic structure inducer (A) is selected from tetramethylammonium compounds, and the organic structure inducer (B) is C 6-16 It is selected from alkylpyridinium compounds, n-octyltrimethylammonium compounds, or combinations thereof.

[0014] In another aspect, a zeolite composition comprising a silicon-aluminum zeolite and a binder according to the present application is provided.

[0015] In another aspect, an application of the silicon-aluminum zeolite or zeolite composition according to the present application as an adsorbent, catalyst, or catalyst carrier is provided.

[0016] In an additional aspect, the present application provides a method for producing p-xylene, comprising the step of reacting a raw material comprising 2,5-dimethylfuran, 2,5-hexanedione, or a combination thereof with ethylene in the presence of a catalyst comprising or composed of the silicon-aluminum zeolite of the present application.

[0017] The zeolite of the present application, which has a novel structure not reported in the prior art, can be used as an adsorbent, a catalyst carrier, or a catalyst. In particular, the zeolite of the present application exhibits high selectivity for p-xylene and cyclic stability when used as a catalyst in the reaction of 2,5-dimethylfuran and / or 2,5-hexanedion for the production of p-xylene. Brief explanation of the drawing

[0018] FIG. 1 shows the X-ray diffraction (XRD) spectrum of the zeolite obtained in Example I-1; FIG. 2 shows a scanning electron microscopy (SEM) image of the zeolite obtained in Example I-1; FIG. 3 shows a transmission electron microscopy (TEM) image of the zeolite obtained in Example I-1; FIG. 4 shows the ammonia temperature programmed desorption (NH3-TPD) spectrum of the zeolite obtained in Example I-1; FIG. 5 shows the pyridine adsorption infrared (Py-FTIR) spectrum of the zeolite obtained in Example I-1; FIG. 6 shows the XRD spectrum of the zeolite obtained in Example I-2; FIG. 7 shows an SEM image of the zeolite obtained in Example I-3; FIG. 8 shows the XRD spectrum of the sample obtained in Comparative Example I-1; FIG. 9 shows the XRD spectrum of the sample obtained in Comparative Example I-3; FIG. 10 shows the XRD spectrum of the sample obtained in Comparative Example I-4; FIG. 11 is a graph showing the conversion rate and p-xylene selectivity of 2,5-dimethylfuran under conditions of recycling SCM-36 zeolite in Example II-15; FIG. 12 shows the NH3-TPD spectrum of the zeolite obtained in Example II-16; Figure 13 shows the Py-FTIR spectrum of the zeolite obtained in Example II-16. Specific details for implementing the invention

[0019] Specific embodiments of the present application will be described in detail as follows. However, it should be noted that the scope of protection of the present application is not limited by these specific embodiments but is determined by the appended claims.

[0020] All disclosures, patent applications, patents, and other references mentioned herein are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used herein have the meaning commonly understood by those skilled in the art. In the event of a conflict, the definitions within this specification shall prevail.

[0021] Where a material, substance, method, step, apparatus, or component is introduced with modifiers such as “known to those skilled in the art,” “prior art,” or similar terms, the subject described by the modifier includes not only those commonly used in the art at the time of filing of this application, but also those not currently commonly used but that will be suitable for similar purposes as recognized in the art in the future.

[0022] In the context of this specification, unless clearly evident, any unmentioned matters are directly applicable to all matters known in the art without the need for any modifications. Furthermore, any embodiment described in this application should be freely combined with one or more other embodiments described herein, and the resulting technical solution or concept is to be considered part of the original invention or original description of this application, but should not be considered new content not disclosed or foreseen in this application unless a person skilled in the art considers such combination to be clearly unreasonable.

[0023] In the context of this specification, the so-called "silicon / aluminum ratio (or Si / Al ratio)" or "silicon / aluminum molar ratio (or Si / Al molar ratio)" refers to the molar ratio of silicon calculated based on SiO2 and aluminum calculated based on Al2O3 within the zeolite.

[0024] In the context of this specification, the so-called “calculated based on oxides” means a calculation based on a stable oxide existing in the highest valence state of the element. For example, regarding the expression “calculated based on oxides,” silicon means a calculation based on SiO2, aluminum means a calculation based on Al2O3, titanium means a calculation based on TiO2, boron means a calculation based on B2O3, zirconium means a calculation based on ZrO2, tin means a calculation based on SnO2, and iron means a calculation based on Fe2O3.

[0025] In the context of this specification, with respect to zeolites, other materials that fill the pore channels during the synthesis of zeolites, excluding water and metal ions (e.g., molecules of organic structure guides, etc.), are referred to as "precursors" before they are removed.

[0026] In the context of this specification, the terms “synthetic state,” “synthetic state form,” or “zeolite in a synthetic state” refer to the state of the zeolite after the completion of the synthesis step and before the start of the post-processing step (e.g., the calcination step). Specific examples of the synthetic state include the state that appears immediately upon the completion of the synthesis step, which is generally referred to as the precursor of the zeolite. In this regard, the zeolite in a synthetic state may contain water and / or organic materials (particularly organic structure-directing agents).

[0027] In the context of this specification, the so-called “calcined,” “calcined form,” or “calcined zeolite” refers to the state of the zeolite after calcination. Specific examples of the state after calcination may be a state resulting from the additional removal of organic matter (particularly organic structure-inducing agents) and moisture from within the pore channels through the calcination of the zeolite in its synthetic state.

[0028] In the context of this specification, within the XRD data of the zeolite, w, m, s, vs, wm, ms, and s-vs, etc., represent the relative intensity I / I0 of the corresponding diffraction peak at an angle 2θ calculated based on the diffraction peak intensity (measured as peak height) relative to the strongest diffraction peak (i.e., the diffraction peak of the highest intensity), where I represents the peak intensity of the corresponding diffraction peak and I0 represents the peak intensity of the strongest diffraction peak; w indicates weak; m indicates moderate; s indicates strong; vs indicates very strong; wm indicates weak to moderate; ms indicates moderate to strong; and s-vs indicates strong to very strong. Such notation methods are familiar to those skilled in the art. Generally speaking, w indicates less than 20; m represents 20 to 40; s represents 40 to 70; vs represents greater than 70; wm represents less than 40; ms represents 20 to 70; and s-vs represents greater than 40.

[0029] In the context of this specification, the structure of the zeolite is determined by an X-ray diffraction spectrum after calcination at 550 °C for 5 hours. The X-ray diffraction spectrum is measured using an X-ray powder diffractometer with a Cu-K α-ray source and a nickel filter. Before testing the sample, the crystallization of the zeolite sample is observed using a scanning electron microscope to confirm whether the sample contains only one type of crystal, that is, whether the zeolite sample is a pure phase. Based on this, an XRD test is performed to confirm whether there are no interference peaks from other crystals within the diffraction peaks of the XRD spectrum.

[0030] According to the present application, the interplanar spacing of various diffraction peaks in the XRD diffraction spectrum of a zeolite can be obtained by calculating based on the 2θ value of the diffraction peaks through the Bragg formula λ=2dsinθ (where λ is the wavelength of the incident wave, λ=1.54 Å, d is the interplanar spacing, and θ is the angle between the incident line and the scattering plane).

[0031] In the context of this specification, the so-called "specific surface area" refers to the total surface area of ​​a sample per unit mass, including the internal surface area and the external surface area. Non-porous samples have only an external surface area, such as Portland cement, some clay mineral powder particles, etc. Porous samples have both an external surface area and an internal surface area, such as asbestos fibers, diatomite, and zeolite. In porous samples, the surface area of ​​pores with a pore size of less than 2 nanometers is the internal surface area, and the surface area excluding the internal surface area is the external surface area. The external surface area of ​​a sample per unit mass is the external specific surface area.

[0032] In the context of this specification, the so-called "pore volume" refers to the pore volume of the zeolite per unit mass. The so-called "total pore volume" refers to the volume of all pores of the zeolite per unit mass. The so-called "microporous volume" refers to the volume of all micropores of the zeolite per unit mass (generally meaning pores with a pore channel diameter of less than 2 nanometers).

[0033] In this application, pore structure parameters of the zeolite material, such as total pore volume, micropore volume, total specific surface area, and external specific surface area, are obtained by measuring and obtaining the nitrogen physical adsorption and desorption isotherms of the zeolite using a physical adsorption instrument (e.g., TriStar 3000 physical adsorption instrument of Micromeritics, USA) and by calculating using the BET method and the t-plot method, wherein the total pore volume is the pore volume corresponding to a relative pressure P / P0 = 0.99. The experimental conditions for the physical adsorption and desorption of nitrogen are: a measurement temperature of -196 °C, vacuum pretreatment of the zeolite at 300 °C for 10 hours prior to measurement, and nitrogen acting as the adsorbent.

[0034] In the context of this specification, the so-called "crystal thickness" refers to the average value of the thickness of all plate-like crystals when the zeolite is observed at a magnification of 100,000x using a transmission electron microscope in a randomly selected observation area. The process was repeated a total of 10 times, and the average value of the 10 average values ​​was taken as the crystal thickness.

[0035] As described above, in the first aspect, the present application provides a silicon-aluminum zeolite having a silicon / aluminum ratio n such that n≥5, where n is preferably in the range of 5 to 80 and more preferably in the range of 10 to 65, and the X-ray diffraction spectrum of the zeolite exhibits relative intensity characteristics of the diffraction peaks as shown in the table below:

[0036] .

[0037] In a preferred embodiment, the X-ray diffraction spectrum of the zeolite also exhibits the relative intensity characteristics of the diffraction peaks as shown in any one column of the following table:

[0038] .

[0039] In a more preferred embodiment, the X-ray diffraction spectrum of the zeolite also exhibits the relative intensity characteristics of the diffraction peaks as shown in any one column of the following table:

[0040] .

[0041] The silicon-aluminum zeolite SCM-36 of the present application has a structure never before obtained in the art. According to the present application, the SCM-36 zeolite may exist in an uncalcined state (synthetic state) or a calcined state. When existing in a synthetic state, the SCM-36 zeolite is typically of the chemical formula "nSiO2·Al2O3·organic structure inducer·water" or "nSiO2·Al2O3·mMO". x It has a schematic chemical composition as indicated by “·organic structure inducer·water”. When existing in a calcined or synthetic state, the SCM-36 zeolite also typically has the chemical formula “nSiO2·Al2O3” or “nSiO2·Al2O3·mMO”. x The zeolite may have a schematic chemical composition as indicated by ", where n represents the silicon / aluminum ratio of the zeolite, n is 5 or greater, and m represents the molar ratio of the silicon element to the element M in the zeolite, and the value of m satisfies that the total content of the element M in the zeolite is 3 mol% or less based on the oxide and the total amount of Si, Al and element M. In the latter case, the zeolite is sometimes known to contain a certain amount of water (especially immediately after synthesis). However, since the presence of water does not substantially affect the XRD spectrum of the zeolite, there is no need to measure the amount of water in this application. In this regard, the schematic chemical composition actually represents the anhydrous chemical composition of the zeolite.

[0042] In a preferred embodiment, the specific surface area of ​​the zeolite determined by the BET method is 300 m² 2 / g to 700 m 2 / g, preferably 300 m 2 / g to 600 m 2 / g, more preferably 350 m 2 / g to 500 m 2 / g, e.g., 360 to 480 m 2 / g and the external specific surface area is 50 m² 2 / g to 300 m 2 / g, preferably 80 m 2 / g to 250 m 2 / g, and more preferably 100 m 2 / g to 220 m 2 / g is.

[0043] In a preferred embodiment, the total pore volume of the zeolite is 0.20 cm³ 3 / g to 1.50 cm 3 / g, preferably 0.40 cm 3 / g to 1.20 cm 3 / g, more preferably 0.5 cm 3 / g to 1.0 cm 3 / g; and the micropore volume determined by the t-plot method is 0.05 cm³ 3 / g to 0.35 cm 3 / g, preferably 0.08 cm 3 / g to 0.30 cm 3 / g, more preferably 0.09 cm 3 / g to 0.25 cm 3 / g is.

[0044] In a preferred embodiment, the zeolite has a nano-flake crystal form with a crystal thickness of less than 30 nanometers, preferably 5 nanometers to 25 nanometers, more preferably 7 nanometers to 20 nanometers, for example 10 nanometers to 20 nanometers.

[0045] In a preferred embodiment, the total acid content of the zeolite determined by the NH3 temperature programmed desorption (NH3-TPD) method is 400 μmol·g -1 to 1200 μmol·g -1 and, preferably 500 μmol·g -1 to 1000 μmol·g -1 However, the content of the weak acid, defined as an acid having a desorption temperature of 100°C to 250°C, is 40% or more, preferably 45% to 90%.

[0046] In a preferred embodiment, the Lewis acid / Brønsted acid ratio of the zeolite measured by pyridine adsorption infrared spectroscopy is 0.1 to 3.8, preferably 0.4 to 3.5.

[0047] In a preferred embodiment, the zeolite further comprises at least one element M selected from the group consisting of titanium, boron, zirconium, tin, iron, or a combination thereof.

[0048] In a more preferred embodiment, the total content of the element M in the zeolite is 3 mol% or less based on the oxide and the total amount of Si, Al, and element M (wherein the amounts of Si, Al, and element M are calculated based on the oxide forms of SiO2, Al2O3, and element M, respectively).

[0049] In a second aspect, the present application provides a method for manufacturing a silicon-aluminum zeolite, comprising the following steps:

[0050] 1) a step of obtaining a zeolite by crystallizing a mixture comprising a silicon source, an aluminum source, an organic structure inducer (A), an organic structure inducer (B), an alkali source, and water; and

[0051] 2) Optionally, a step of calcining the zeolite obtained in step 1);

[0052] Here, the organic structure indicator (A) is selected from tetramethylammonium compounds, and the organic structure indicator (B) is C 6-16 It is selected from alkylpyridinium compounds, n-octyltrimethylammonium compounds, or combinations thereof.

[0053] In a preferred embodiment, the molar ratio of silicon source (calculated based on SiO2) to aluminum source (calculated based on Al2O3) to organic structure inducer (A) to organic structure inducer (B) to alkali source to water in the mixture of step 1) is 1:(0.01-0.20):(0.05-0.80):(0.05-0.80):(0.05-0.50):(8-80), preferably 1:(0.01-0.10):(0.08-0.65):(0.08-0.65):(0.08-0.45):(10-70), more preferably 1:(0.02-0.07):(0.10-0.50):(0.10-0.50):(0.10-0.40):(12-60).

[0054] In the method of the present application, crystallization in step 1) can be carried out in any manner commonly known in the art, for example, a method of mixing a silicon source, an aluminum source, an organic structure inducer, an alkali source, and water in a predetermined ratio, and hydrothermally crystallizing the obtained mixture under crystallization conditions.

[0055] In a preferred embodiment, in step 1) the crystallization temperature of the crystallization is 120 ℃ to 200 ℃ and the crystallization time is 1 day to 15 days; preferably, the crystallization temperature is 130 ℃ to 190 ℃ and the crystallization time is 2 days to 12 days; more preferably, the crystallization temperature is 140 ℃ to 180 ℃ and the crystallization time is 3 days to 9 days.

[0056] In the method of the present application, after crystallization in step 1) is completed, the zeolite may be separated as a product from the resulting mixture through any commonly known separation method to obtain the silicon-aluminum zeolite SCM-36 of the present application. Regarding the separation method, for example, methods of filtering, washing, and drying the resulting mixture may be exemplified. Here, filtration, washing, and drying may be performed by any method commonly known in the art. Specifically, as an example of filtration, the resulting mixture may be, for example, suction filtered; as an example of washing, deionized water may be, for example, used for washing; and as an example of drying, the sample may be, for example, placed in a commercially available blast drying oven for drying. The drying temperature may be 40 °C to 150 °C, preferably 50 °C to 120 °C; and the drying time may be 1 hour to 30 hours, preferably 2 hours to 24 hours. Drying may be performed under atmospheric pressure or reduced pressure.

[0057] In the method of the present application, if desired, the zeolite obtained in step 1) may be calcined to remove organic structure-directing agents and possible water in order to obtain a calcined zeolite (also the SCM-36 zeolite of the present invention). Calcination may be performed by any method commonly known in the art. For example, the calcination temperature is generally in the range of 300 °C to 800 °C, preferably 400 °C to 650 °C, and the calcination time is generally in the range of 1 hour to 12 hours, preferably 2 hours to 10 hours. Furthermore, the calcination is generally performed in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0058] According to the present application, the silicon source and aluminum source may be various silicon sources and aluminum sources commonly used in the manufacture of silicon-aluminum zeolites, and the present application does not impose strict limitations thereon. In a preferred embodiment, the silicon source is selected from the group consisting of silicon acid, silica gel, silica sol, tetraethyl silicate, sodium silicate, or combinations thereof; and the aluminum source is selected from the group consisting of aluminum hydroxide, aluminum oxide, aluminate, aluminum salt, and tetraalkoxyaluminum, or combinations thereof.

[0059] According to the present application, the alkali source may be any alkali source commonly used in the process of manufacturing silicon-aluminum zeolite, and the present application does not impose strict limitations thereon. In a preferred embodiment, the alkali source is selected from the group consisting of inorganic alkyls having alkali metals and / or alkaline earth metals as cations, or combinations thereof. For example, the alkali source may be selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, or combinations thereof.

[0060] According to the present application, the organic structure inducer (A) is (CH3)4N as a cation + A tetramethylammonium compound having is selected from, for example, tetramethylammonium hydroxide, tetramethylammonium organic salts and tetramethylammonium inorganic salts. In a preferred embodiment, the organic structure inducer (A) is selected from the group consisting of tetramethylammonium hydroxide, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, or a combination thereof.

[0061] According to the present application, the organic structure inducer (B) is a cation R(C5H5N) + It is selected from pyridinium compounds having, where R is C 10-16Alkyl group, C8H as a cation 17 (CH3)3N + n-octyltrimethylammonium compounds having, or a combination thereof, e.g., C 10-16 Alkylpyridinium hydroxide, C 10-16 Alkylpyridinium organic acid salt, C 10-16 alkylpyridinium inorganic salt, n-octyltrimethylammonium hydroxide, n-octyltrimethylammonium organic salt, and n-octyltrimethylammonium inorganic salt. In a preferred embodiment, the organic structure inducer (B) is selected from the group consisting of hexadecylpyridine bromide, tetradecylpyridine bromide, dodecylpyridine bromide, decylpyridine bromide, hexadecylpyridine chloride, tetradecylpyridine chloride, hexadecylpyridine hydroxide, n-octyltrimethylammonium chloride, n-octyltrimethylammonium bromide, n-octyltrimethylammonium hydroxide, or a combination thereof. More preferably, the organic structure inducer (B) is selected from the group consisting of hexadecylpyridine bromide, tetradecylpyridine bromide, dodecylpyridine bromide, hexadecylpyridine chloride, hexadecylpyridine hydroxide, n-octyltrimethylammonium chloride, n-octyltrimethylammonium bromide, or a combination thereof.

[0062] In a preferred embodiment, the mixture of step 1) further comprises at least one source of element M selected from the group consisting of titanium, boron, zirconium, tin, and iron.

[0063] In a more preferred embodiment, the titanium source is selected from a titanium-containing organometallic complex, tetraalkoxytitanium, titanium dioxide, titanium nitrate, or a combination thereof; the boron source is selected from boric acid, borate, borex, boron trioxide, or a combination thereof; the zirconium source is selected from a zirconium-containing organometallic complex, zirconium salt, zirconium hydroxide, zirconium alcoholate, zirconium dioxide, or a combination thereof; the tin source is selected from a tin-containing organometallic complex, tin salt, tin dioxide, or a combination thereof; and the iron source is selected from an iron-containing organometallic complex, iron nitrite, iron chloride, iron oxide, or a combination thereof.

[0064] In a more preferred embodiment, the molar ratio of the silicon source (calculated based on SiO2) to the source of element M (calculated based on the corresponding oxide) is 1:(0.002-0.10), preferably 1:(0.005-0.05).

[0065] In a third aspect, a silicon-aluminum zeolite SCM-36 prepared according to the method of the present application is provided.

[0066] The silicon-aluminum zeolite SCM-36 of the present application may be obtained and used in any physical form, such as powder, particles, or molded articles (e.g., strips, clovers, etc.). This physical form may be obtained by any method commonly known in the art without any particular limitations.

[0067] In a fourth aspect, the present application provides a zeolite composition comprising a silicon-aluminum zeolite SCM-36 according to the present application or a silicon-aluminum zeolite SCM-36 prepared according to the method of the present application and a binder.

[0068] The silicon-aluminum zeolite SCM-36 of the present application may be used in combination with additional materials to obtain a zeolite composition. Examples of such additional materials may include active materials and inert materials. Examples of the active materials may include synthetic zeolites, natural zeolites, or other types of zeolites. The inert materials (generally referred to as binders) are not strictly limited in the present application. For example, the inert materials may be materials commonly used to manufacture adsorbents or catalysts, including but not limited to clay, carclazite, silica, silica gel, alumina, or mixtures thereof. These additional materials may be used alone or in combination in any proportion. The amount of the additional materials may directly mean the amount customary in the art without any special limitations.

[0069] According to the present application, the zeolite composition may exist in any physical form, such as powder, particles, or molded articles (e.g., strips, clovers, etc.). These physical forms may be obtained by any method commonly known in the art without any particular limitation.

[0070] In a fifth aspect, the present application provides the silicon-aluminum zeolite SCM-36 or zeolite composition, or the silicon-aluminum zeolite SCM-36 prepared according to the method of the present application, for use as an adsorbent, catalyst, or catalyst carrier.

[0071] The SCM-36 zeolite or zeolite composition of the present application may be used as an adsorbent for separating at least one component from a mixture of a plurality of components that are, for example, in a gaseous or liquid phase. Based on this, the at least one component may be partially or substantially completely separated from a mixture of various components by, for example, specifically by contacting the mixture with the SCM-36 zeolite or zeolite composition to selectively adsorb the component. Examples of use as an adsorbent may include removing small amounts of moisture from organic solvents such as isopropanol, isobutanol, and isobutylketone, and adsorbing and removing small amounts of moisture from natural gas.

[0072] Furthermore, the SCM-36 zeolite or zeolite composition of the present application may also be used as a catalyst support, a catalyst, or a catalytically active component thereof immediately after or after the necessary processing or conversion (e.g., ion exchange) typically performed on zeolites in the art. For example, the SCM-36 zeolite may be used as a catalyst support. For example, a Pd / SCM-36 may be obtained by loading the metal Pd onto the SCM-36 zeolite to be used as a Pd catalyst for hydrogenation or dehydrogenation reactions, where SCM-36 is the support; the SCM-36 may also be used as a dual-function catalyst, serving not only as a support for the metal Pd but also as a solid acid catalyst material providing acid sites. Furthermore, a desired product may be obtained by carrying out a planned reaction with a reactant (e.g., a hydrocarbon) in the presence of a catalyst comprising the SCM-36 zeolite or zeolite composition of the present application. Examples of planned reactions may include a reaction to convert methanol into olefins or aromatic hydrocarbons by thermal decomposition of isopropylbenzene, and a reaction to produce p-xylene by reacting a feedstock of 2,5-dimethylfuran and / or 2,5-hexanedione with ethylene.

[0073] In a sixth aspect, the present application provides a catalyst comprising or composed of the silicon-aluminum zeolite SCM-36 or zeolite composition of the present application, or a silicon-aluminum zeolite SCM-36 prepared according to the method of the present application.

[0074] In a preferred embodiment, the catalyst is suitable for a reaction that converts methanol into an olefin or aromatic hydrocarbon by thermal decomposition of isopropylbenzene and a reaction that produces p-xylene by reacting a feedstock of 2,5-dimethylfuran and / or 2,5-hexanedionion with ethylene.

[0075] In a seventh aspect, the present application provides a method for producing p-xylene, comprising the step of reacting a raw material comprising 2,5-dimethylfuran, 2,5-hexanedione, or a combination thereof with ethylene in the presence of a catalyst comprising or composed of the silicon-aluminum zeolite SCM-36 of the present application.

[0076] The method for producing p-xylene according to the present application utilizes SCM-36 zeolite as a catalyst or catalytic active component. Under mild reaction conditions, 2,5-dimethylfuran and / or 2,5-hexanedione can be very efficiently converted to p-xylene at a very high conversion rate with very high selectivity for the p-xylene product. Meanwhile, the content of key impurities (e.g., polyalkylbenzene, 2,5-hexanedione, and 2-cyclopenthenone) in the obtained product is extremely low, significantly reducing separation energy consumption. Furthermore, the SCM-36 zeolite used as a catalyst in the present application exhibits high stability, and there is no significant change in catalytic performance even after four repetitions.

[0077] In a preferred embodiment, the contact reaction is carried out in the presence of an organic solvent, and the type of organic solvent can be selected from a wide range. All common organic solvents are applicable in this application. Preferably, the organic solvent is selected from the group consisting of n-hexane, n-heptane, γ-valerolactone, tetrahydrofuran, toluene, cyclohexane, or combinations thereof. The amount of organic solvent can be selected from a wide range and can also be determined based on reaction requirements. In a preferred embodiment, the mass ratio of organic solvent to raw material is 8-60:1, preferably 10-30:1, which is advantageous for increasing the substrate conversion rate and selectivity of the p-xylene product and reducing the content of key impurities in the product.

[0078] In the method of the present application, the amount of catalyst can be selected within a wide range and can also be specifically measured based on reaction requirements. In a preferred embodiment, the mass ratio of the raw material to the catalyst is 0.6-30:1, preferably 1.0-10:1, which is advantageous for increasing the substrate conversion rate and the selectivity of the p-xylene product and reducing the content of key impurities in the product.

[0079] In the method of the present application, conditions for the contact reaction can be selected within a wide range and can also be determined specifically based on reaction requirements. In a preferred embodiment, the reaction conditions include: a reaction temperature of 160 °C to 340 °C, preferably 220 °C to 270 °C; a reaction time can be determined based on the temperature, for example, the reaction time can be 6 hours to 64 hours, preferably 8 hours to 48 hours, more preferably 18 hours to 40 hours; and a reaction pressure of 1 MPa to 8 MPa, preferably 2 MPa to 4 MPa.

[0080] Examples

[0081] The technical solution of the present application is further explained in detail through examples. However, the scope of protection of the present application is not limited to these examples.

[0082] In the following examples and comparative examples, unless otherwise specified, all reagents and raw materials used are commercially available products with analytical purity.

[0083] In the following examples and comparative examples where specific conditions for the experimental method are not specified, the experimental conditions should be selected according to conventional methods and conditions or commercial standards.

[0084] In the following examples and comparative examples, the XRD of the zeolite product was measured in the following manner: the phase of the sample was analyzed using a Panalytical X PERPRO X-ray powder diffractometer having a CuKα-ray source (λ=1.54Å), a nickel filter, a 2θ scanning range of 2° to 50°, an operating voltage of 40 KV, a current of 40 mA, and a scanning speed of 10° / min.

[0085] In the following examples and comparative examples, the inductively coupled plasma atomic emission spectrometer (ICP) used was the Varian 725-ES model, and the content of elements in the sample was detected and determined by dissolving the sample in hydrofluoric acid.

[0086] In the following examples and comparative examples, NH3 temperature programmed desorption (NH3-TPD) experiments were performed on a TPD / TPR Altamira AMI-3300 instrument, and the total acid amount was calculated by peak fitting of the resulting spectrum. Acids corresponding to desorption temperatures of 100 °C to 250 °C were defined as weak acids, and the proportion of weak acids was calculated accordingly.

[0087] In the following examples and comparative examples, scanning electron microscope images were obtained using a field emission scanning electron microscope, specifically the Hitachi S-4800II model from Hitachi Company, Japan, under a test voltage of 15 kV. A transmission electron microscope, specifically the G2F30 from FEI, Netherlands, with an operating voltage of 300 kV, was used. Zeolites were observed at a magnification of 100,000x, and the thickness of all crystals within a randomly selected observation area was measured. After repeating the process five times, the average of the five measurements was taken as the average thickness of the crystals.

[0088] In the following examples and comparative examples, Py-FTIR spectra were tested using a Thermo Nicolet 5700FT-IR spectrometer.

[0089] Example I-1

[0090] A mixture was prepared by homogeneously mixing 24.73 g of deionized water, 6.89 g of sodium hydroxide solution (containing 10 wt.% NaOH), 5.35 g of organic structure inducer (A): tetramethylammonium hydroxide (containing 25 wt.% TMAOH), 3.05 g of organic structure inducer (B): n-octyltrimethylammonium chloride, 1.234 g of sodium metaaluminate (containing 40.5 wt.% Al2O3 and 30.6 wt.% Na2O), and 14.72 g of silica sol (containing 40 wt.% SiO2). The material ratios (molar ratios) of the reactants are as follows:

[0091] Al2O3 / SiO2=0.05

[0092] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0093] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0094] NaOH / SiO2=0.30

[0095] H2O / SiO2=25 and;

[0096] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0097] XRD spectrum data of the dried sample is shown in Table I-1 and Figure 1, SEM image of the sample is shown in Figure 2, and TEM image is shown in Figure 3.

[0098] [Table I-1 XRD Spectrum Data of Zeolite Produced in Example I-1]

[0099]

[0100] The generated calcination product has a specific surface area of ​​380 m² 2 / g, external specific surface area is 170 m² 2 / g, total pore volume is 0.92 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 15 nanometers.

[0101] The calcined sample has a SiO2 / Al2O3 ratio of 21.6 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0102] Ammonia temperature-programmed desorption of the generated sample (ammonia) The spectrum of temperature programmed desorption (NH3-TPD) is shown in Fig. 4. As a result, the total acid content is 782 μmol·g -1 The weak acid content is 63%. The infrared spectrum of pyridine adsorption is shown in Fig. 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.2.

[0103] Example I-2

[0104] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0105] Al2O3 / SiO2=0.067

[0106] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0107] n-octyltrimethylammonium chloride (B) / SiO2=0.20

[0108] NaOH / SiO2=0.30

[0109] H2O / SiO2=25 and;

[0110] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 5 days. Once crystallization was complete, the product was filtered, washed, dried in a 100 °C oven for 16 hours, and calcined in air at 550 °C for 8 hours to obtain zeolite.

[0111] XRD spectrum data of the dried sample are shown in Table I-2 and Figure 6, and the SEM image of the sample is similar to that shown in Figure 2.

[0112] [Table I-2 XRD Spectrum Data of Zeolite Produced in Example I-2]

[0113]

[0114] The generated calcination product has a specific surface area of ​​392 m² 2 / g, external specific surface area is 166 m² 2 / g, total pore volume is 0.73 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 12 nanometers.

[0115] The calcined sample has a SiO2 / Al2O3 ratio of 15.6 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0116] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 827 μmol·g -1 The weak acid content is 61%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.5.

[0117] Example I-3

[0118] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0119] Al2O3 / SiO2=0.04

[0120] Tetramethylammonium chloride (A) / SiO2=0.20

[0121] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0122] NaOH / SiO2=0.25

[0123] H2O / SiO2=35 and;

[0124] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 155 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in an 80 °C oven for 16 hours, and calcined in air at 500 °C for 10 hours to obtain zeolite.

[0125] XRD spectrum data of the dried sample is shown in Table I-3, and SEM images of the sample are shown in Figure 7.

[0126] [Table I-3 XRD Spectrum Data of Zeolite Produced in Example I-3]

[0127]

[0128] The generated calcination product has a specific surface area of ​​388 m² 2 / g, external specific surface area is 162 m² 2 / g, total pore volume is 0.75 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 13 nanometers.

[0129] The calcined sample has a SiO2 / Al2O3 ratio of 26.1 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0130] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 674 μmol·g -1 The weak acid content is 68%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 1.1.

[0131] Example I-4

[0132] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0133] Al2O3 / SiO2=0.045

[0134] Tetramethylammonium hydroxide (A) / SiO2=0.25

[0135] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0136] NaOH / SiO2=0.20

[0137] H2O / SiO2=45 and;

[0138] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 165 °C for 4 days. Once crystallization was complete, the product was filtered, washed, dried in a 60 °C oven for 24 hours, and calcined in air at 600 °C for 4 hours to obtain zeolite.

[0139] XRD spectrum data of the dried sample is shown in Table I-4, and the SEM image of the sample is similar to that shown in Figure 2.

[0140] [Table I-4 XRD Spectrum Data of Zeolite Produced in Example I-4]

[0141]

[0142] The generated calcination product has a specific surface area of ​​377 m² 2 / g, external specific surface area is 158 m² 2 / g, total pore volume is 0.74 cm³ 3 / g, and the micropore volume is 0.11 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 11 nanometers.

[0143] The calcined sample has a SiO2 / Al2O3 ratio of 22.3 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0144] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 835 μmol·g -1 The weak acid content is 64%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.8.

[0145] Example I-5

[0146] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0147] Al2O3 / SiO2=0.017

[0148] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0149] n-octyltrimethylammonium chloride (B) / SiO2=0.25

[0150] NaOH / SiO2=0.20

[0151] H2O / SiO2=30 and;

[0152] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 155 °C for 8 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 120 °C for 6 hours, and calcined in air at 550 °C for 8 hours to obtain zeolite.

[0153] XRD spectrum data of the dried sample is shown in Table I-5, and the SEM image of the sample is similar to that shown in Figure 2.

[0154] [Table I-5 XRD Spectrum Data of Zeolite Produced in Example I-5]

[0155]

[0156] The generated calcination product has a specific surface area of ​​372 m² 2 / g, external specific surface area is 149 m² 2 / g, total pore volume is 0.74 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 12 nanometers.

[0157] The calcined sample has a SiO2 / Al2O3 ratio of 61.5 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0158] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 621 μmol·g -1The weak acid content is 56%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured as 1.0.

[0159] Example I-6

[0160] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0161] Al2O3 / SiO2=0.03

[0162] Tetramethylammonium iodide(A) / SiO2=0.20

[0163] n-octyltrimethylammonium chloride (B) / SiO2=0.20

[0164] NaOH / SiO2=0.25

[0165] H2O / SiO2=35 and;

[0166] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 170 °C for 5 days. Once crystallization was complete, the product was filtered, washed, dried in a 100 °C oven for 12 hours, and calcined in air at 500 °C for 10 hours to obtain zeolite.

[0167] XRD spectrum data of the dried sample is shown in Table I-6, and the SEM image of the sample is similar to that shown in Figure 2.

[0168] [Table I-6 XRD Spectrum Data of Zeolite Produced in Example I-6]

[0169]

[0170] The generated calcination product has a specific surface area of ​​362 m² 2 / g, external specific surface area is 149 m² 2 / g, total pore volume is 0.67 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 12 nanometers.

[0171] The calcined sample has a SiO2 / Al2O3 ratio of 34.5 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0172] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 643 μmol·g -1 The weak acid content is 66%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.1.

[0173] Example I-7

[0174] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0175] Al2O3 / SiO2=0.05

[0176] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0177] Tetradecylpyridine bromide (B) / SiO2=0.15

[0178] NaOH / SiO2=0.30

[0179] H2O / SiO2=35 and;

[0180] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 6 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0181] XRD spectrum data of the dried sample is shown in Table I-7, and the SEM image of the sample is similar to that shown in Figure 2.

[0182] [Table I-7 XRD Spectrum Data of Zeolite Produced in Example I-7]

[0183]

[0184] The generated calcination product has a specific surface area of ​​378 m² 2 / g, external specific surface area is 156 m² 2 / g, total pore volume is 0.77 cm³ 3 / g, and the micropore volume is 0.11 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 13 nanometers.

[0185] The calcined sample has a SiO2 / Al2O3 ratio of 21.1 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0186] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 815 μmol·g -1 The weak acid content is 68%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 1.7.

[0187] Example I-8

[0188] Tests were performed with reference to Example I-1, except that hexadecylpyridine bromide was used as the organic structure guide (B) and the material ratio (molar ratio) of the reactants was as follows:

[0189] Al2O3 / SiO2=0.045

[0190] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0191] Hexadecylpyridine bromide (B) / SiO2=0.20

[0192] NaOH / SiO2=0.25

[0193] H2O / SiO2=30 and;

[0194] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in a 90 °C oven for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0195] XRD spectrum data of the dried sample is shown in Table I-8, and the SEM image of the sample is similar to that shown in Figure 2.

[0196] [Table I-8 XRD Spectrum Data of Zeolite Produced in Example I-8]

[0197]

[0198] The generated calcination product has a specific surface area of ​​394 m² 2 / g, external specific surface area is 171 m² 2 / g, total pore volume is 0.68 cm³ 3 / g, and the micropore volume is 0.12 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 12 nanometers.

[0199] The calcined sample has a SiO2 / Al2O3 ratio of 22.8 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0200] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Figure 4. As a result, the total acid content is 848 μmol·g -1 The weak acid content is 59%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.3.

[0201] Example I-9

[0202] Tests were performed with reference to Example I-8, except that the reactants and material ratios (molar ratios) used were as follows:

[0203] Al2O3 / SiO2=0.068

[0204] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0205] Hexadecylpyridine bromide (B) / SiO2=0.15

[0206] NaOH / SiO2=0.30

[0207] H2O / SiO2=40 and;

[0208] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an 80 °C oven for 16 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0209] XRD spectrum data of the dried sample is shown in Table I-9, and the SEM image of the sample is similar to that shown in Figure 2.

[0210] [Table I-9 XRD Spectrum Data of Zeolite Produced in Example I-9]

[0211]

[0212] The generated calcination product has a specific surface area of ​​372 m² 2 / g, external specific surface area is 144 m² 2 / g, total pore volume is 0.65 cm³ 3 / g, and the micropore volume is 0.11 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 15 nanometers.

[0213] The calcined sample has a SiO2 / Al2O3 ratio of 14.5 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0214] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 896 μmol·g -1 The weak acid content is 82%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 3.0.

[0215] Example I-10

[0216] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0217] Al2O3 / SiO2=0.05

[0218] TiO2 / SiO2=0.01

[0219] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0220] n-octyltrimethylammonium chloride (B) / SiO2=0.20

[0221] NaOH / SiO2=0.25

[0222] H2O / SiO2=35 and;

[0223] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in a 100 °C oven for 10 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0224] XRD spectrum data of the dried sample is shown in Table I-10, and the SEM image of the sample is similar to that shown in Figure 2.

[0225] [Table I-10 XRD Spectrum Data of Zeolite Produced in Example I-10]

[0226]

[0227] The generated calcination product has a specific surface area of ​​364 m² 2 / g, external specific surface area is 146 m² 2 / g, total pore volume is 0.71 cm³ 3 / g, and the micropore volume is 0.12 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 18 nanometers.

[0228] The calcined sample has SiO2 / Al2O3 = 21.2 (molar ratio) and SiO2 / TiO2 = 106.2 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0229] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 795 μmol·g -1 The weak acid content is 60%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 1.6.

[0230] Example I-11

[0231] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0232] Al2O3 / SiO2=0.065

[0233] B2O3 / SiO2=0.012

[0234] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0235] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0236] NaOH / SiO2=0.30

[0237] H2O / SiO2=40 and;

[0238] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 155 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in an 80 °C oven for 8 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0239] XRD spectrum data of the dried sample is shown in Table I-11, and the SEM image of the sample is similar to that shown in Figure 2.

[0240] [Table I-11 XRD Spectrum Data of Zeolite Produced in Example I-11]

[0241]

[0242] The generated calcination product has a specific surface area of ​​385 m² 2 / g, external specific surface area is 152 m² 2 / g, total pore volume is 0.63 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 20 nanometers.

[0243] The calcined sample has SiO2 / Al2O3 = 15.9 (molar ratio) and SiO2 / B2O3 = 96.3 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0244] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 860 μmol·g -1 The weak acid content is 74%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 3.2.

[0245] Example I-12

[0246] Tests were performed with reference to Example I-7, except that the reactants and material ratios (molar ratios) used were as follows:

[0247] Al2O3 / SiO2=0.035

[0248] ZrO2 / SiO2=0.008

[0249] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0250] Dodecylpyridine bromide (B) / SiO2=0.20

[0251] NaOH / SiO2=0.25

[0252] H2O / SiO2=30 and;

[0253] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 165 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 5 hours to obtain zeolite.

[0254] XRD spectrum data of the dried sample is shown in Table I-12, and the SEM image of the sample is similar to that shown in Figure 2.

[0255] [Table I-12 XRD Spectrum Data of Zeolite Produced in Example I-12]

[0256]

[0257] The generated calcination product has a specific surface area of ​​373 m² 2 / g, external specific surface area is 148 m² 2 / g, total pore volume is 0.75 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 16 nanometers.

[0258] The calcined sample has SiO2 / Al2O3 = 30.6 (molar ratio) and SiO2 / ZrO3 = 131.2 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0259] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 773 μmol·g -1 The weak acid content is 63%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.8.

[0260] Example I-13

[0261] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0262] Al2O3 / SiO2=0.05

[0263] SnO2 / SiO2=0.008

[0264] Tetramethylammonium bromide (A) / SiO2=0.15

[0265] n-octyltrimethylammonium bromide (B) / SiO2=0.20

[0266] NaOH / SiO2=0.30

[0267] H2O / SiO2=25 and;

[0268] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 550 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0269] XRD spectrum data of the dried sample is shown in Table I-13, and the SEM image of the sample is similar to that shown in Figure 2.

[0270] [Table I-13 XRD Spectrum Data of Zeolite Produced in Example I-13]

[0271]

[0272] The generated calcination product has a specific surface area of ​​386 m² 2 / g, external specific surface area is 154 m² 2 / g, total pore volume is 0.73 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 15 nanometers.

[0273] The calcined sample has SiO2 / Al2O3 = 21.5 (molar ratio) and SiO2 / SnO3 = 126.4 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0274] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 794 μmol·g -1 The weak acid content is 66%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.4.

[0275] Example I-14

[0276] Tests were performed with reference to Example I-8, except that the reactants and material ratios (molar ratios) used were as follows:

[0277] Al2O3 / SiO2=0.04

[0278] Fe2O3 / SiO2=0.005

[0279] Tetramethylammonium chloride (A) / SiO2=0.15

[0280] Hexadecylpyridine hydroxide (B) / SiO2=0.25

[0281] NaOH / SiO2=0.20

[0282] H2O / SiO2=30 and;

[0283] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 165 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0284] XRD spectrum data of the dried sample is shown in Table I-14, and the SEM image of the sample is similar to that shown in Figure 2.

[0285] [Table I-14 XRD Spectrum Data of Zeolite Produced in Example I-14]

[0286]

[0287] The generated calcination product has a specific surface area of ​​383 m² 2 / g, external specific surface area is 155 m² 2 / g, total pore volume is 0.75 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 17 nanometers.

[0288] The calcined sample has SiO2 / Al2O3 = 26.5 (molar ratio) and SiO2 / Fe2O3 = 188.4 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0289] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 787 μmol·g -1 The weak acid content is 68%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 1.8.

[0290] Example I-15

[0291] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0292] Al2O3 / SiO2=0.045

[0293] Tetramethylammonium hydroxide (A) / SiO2=0.45

[0294] Dodecylpyridine bromide (B) / SiO2=0.20

[0295] NaOH / SiO2=0.25

[0296] H2O / SiO2=25 and;

[0297] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0298] XRD spectrum data of the dried sample is shown in Table I-15, and the SEM image of the sample is similar to that shown in Figure 2.

[0299] [Table I-15 XRD Spectrum Data of Zeolite Produced in Example I-15]

[0300]

[0301] The generated calcination product has a specific surface area of ​​368 m² 2 / g, external specific surface area is 145 m² 2 / g, total pore volume is 0.72 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 17 nanometers.

[0302] The calcined sample has a SiO2 / Al2O3 ratio of 22.8 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0303] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 861 μmol·g -1 The weak acid content is 57%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 2.0.

[0304] Example I-16

[0305] Tests were performed with reference to Example I-7. The reactants and material ratios (molar ratios) used are as follows:

[0306] Al2O3 / SiO2=0.040

[0307] Tetramethylammonium chloride (A) / SiO2=0.15

[0308] Dodecylpyridine bromide (B) / SiO2=0.45

[0309] NaOH / SiO2=0.15

[0310] H2O / SiO2=30 and;

[0311] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 8 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0312] XRD spectrum data of the dried sample is shown in Table I-16, and the SEM image of the sample is similar to that shown in Figure 2.

[0313] [Table I-16 XRD Spectrum Data of Zeolite Produced in Example I-16]

[0314]

[0315] The generated calcination product has a specific surface area of ​​388 m² 2 / g, external specific surface area is 159 m² 2 / g, total pore volume is 0.71 cm³ 3 / g, and the micropore volume is 0.10 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 17 nanometers.

[0316] The calcined sample has a SiO2 / Al2O3 ratio of 26.1 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0317] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 872 μmol·g -1 The weak acid content is 75%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 3.0.

[0318] Example I-17

[0319] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0320] Al2O3 / SiO2=0.05

[0321] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0322] Hexadecylpyridine chloride (B) / SiO2=0.25

[0323] NaOH / SiO2=0.15

[0324] H2O / SiO2=20 and;

[0325] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 7 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0326] XRD spectrum data of the dried sample is shown in Table I-17, and the SEM image of the sample is similar to that shown in Figure 2.

[0327] [Table I-17 XRD Spectrum Data of Zeolite Produced in Example I-17]

[0328]

[0329] The generated calcination product has a specific surface area of ​​392 m² 2 / g, external specific surface area 159 m² 2 / g, total pore volume is 0.72 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes, and the crystal thickness is approximately 15 nanometers.

[0330] The calcined sample has a SiO2 / Al2O3 ratio of 21.6 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0331] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is similar to that shown in Fig. 4. As a result, the total acid content is 908 μmol·g -1 The weak acid content is 79%. The infrared spectrum of pyridine adsorption is similar to that shown in Figure 5, and the Lewis / Bronstead acid ratio was analyzed and measured to be 3.2.

[0332] Comparative Example I-1

[0333] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0334] Al2O3 / SiO2=0.22

[0335] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0336] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0337] NaOH / SiO2=0.30

[0338] H2O / SiO2=25 and;

[0339] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0340] XRD spectrum data of the dried sample is shown in Fig. 8. The dried sample is an amorphous material, not SCM-36 zeolite.

[0341] Comparative Example I-2

[0342] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0343] Al2O3 / SiO2=0.05

[0344] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0345] n-octyltrimethylammonium chloride (B) / SiO2=0.15

[0346] NaOH / SiO2=0.55

[0347] H2O / SiO2=25 and;

[0348] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0349] The XRD spectrum data of the dried sample is similar to that shown in Fig. 8. The dried sample is an amorphous material, not SCM-36 zeolite.

[0350] Comparative Example I-3

[0351] Tests were performed with reference to Example I-1, except that octylamine was used as the organic structure guide (B) and the material ratio (molar ratio) of the reactants was as follows:

[0352] Al2O3 / SiO2=0.05

[0353] Tetramethylammonium hydroxide (A) / SiO2=0.15

[0354] Octylamine(B) / SiO2=0.15

[0355] NaOH / SiO2=0.30

[0356] H2O / SiO2=25 and;

[0357] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0358] XRD spectrum data of the dried sample is shown in Fig. 8. The dried sample is a mixture of MOR and another zeolite having a different structure, not SCM-36 zeolite.

[0359] Comparative Example I-4

[0360] Tests were performed with reference to Example I-1, except that only tetramethylammonium hydroxide was used as the organic structure guide and the material ratio (molar ratio) of the reactants was as follows:

[0361] Al2O3 / SiO2=0.05

[0362] Tetramethylammonium hydroxide / SiO2=0.15

[0363] NaOH / SiO2=0.30

[0364] H2O / SiO2=25 and;

[0365] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 160 °C for 6 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 110 °C for 12 hours, and calcined in air at 550 °C for 6 hours to obtain zeolite.

[0366] XRD spectrum data of the dried sample is shown in Fig. 10. The dried sample is a mixture of SOD and zeolite having another structure, not SCM-36 zeolite.

[0367] Example I-18

[0368] The zeolite synthesized in Example I-5 was ion-exchanged with 0.5 mol / L of NH4Cl solution (mass ratio of zeolite to ammonium chloride solution was 1:20) at 70 °C for 2 hours, followed by centrifugation and washing. The sample obtained from two ion exchanges was dried at 100 °C for 12 hours, and then calcined at 550 °C for 6 hours to obtain H-type SCM-36 zeolite.

[0369] The above calcined H-type SCM-36 zeolite powder sample was crushed, and a portion of the sample with a particle size of 20 to 40 mesh was sieved and placed in a fixed-bed reactor for the thermal decomposition reaction of isopropylbenzene. The reaction conditions were as follows: reaction temperature 320 °C, reaction pressure atmospheric pressure, and isopropylbenzene weight-hour space velocity 2 h -1 The product was analyzed using a Shimadzu GC-2014 gas chromatograph. After 1 hour of reaction, the conversion rate of isopropylbenzene was 25.2%, and the selectivity of benzene in the product was 94.1%.

[0370] In this embodiment, isopropylbenzene was used as a raw material to carry out a thermal decomposition reaction of isopropylbenzene, and the decomposition was performed under the action of a catalyst to produce products such as propylene and benzene.

[0371] Conversion rate of isopropyl benzene % = (Molar feed of isopropyl benzene - Molar amount of isopropyl benzene in product) / (Molar feed of isopropyl benzene) x 100 %.

[0372] Selectivity of benzene % = (Molar amount of benzene in the product) / (Total molar amount of aromatic hydrocarbons in the product) x 100 %, wherein;

[0373] Aromatic hydrocarbons in the product do not contain isopropylbenzene raw materials.

[0374] Example I-19

[0375] The zeolite synthesized in Example I-5 was ion-exchanged with 0.5 mol / L of NH4Cl solution (mass ratio of zeolite to ammonium chloride solution was 1:20) at 70 °C for 2 hours, followed by centrifugation and washing. The sample obtained from two ion exchanges was dried at 100 °C for 12 hours, and then calcined at 550 °C for 6 hours to obtain H-type SCM-36 zeolite.

[0376] The above calcined H-type SCM-36 zeolite powder sample was crushed, and a portion of the sample with a particle size of 20 to 40 mesh was sieved and placed in a fixed-bed reactor for the methanol conversion reaction. The reaction conditions were as follows: reaction temperature 460 °C, reaction pressure 0.1 MPa, and space velocity of methanol feedstock 1 h⁻¹ per hour. -1 The product was analyzed using a Shimadzu GC-2014 gas chromatograph. After 45 minutes of reaction, the methanol conversion rate was 99.0%, the selectivity for C2 to C4 olefins in the product was 58.6%, and the selectivity for aromatic hydrocarbons was 4.2%.

[0377] In this embodiment, the methanol conversion reaction was the conversion of a methanol feedstock into hydrocarbons such as olefins and aromatic hydrocarbons under the action of a catalyst.

[0378] The conversion rate of methanol % = (molar amount of feed methanol - molar amount of methanol in product - 2 x molar amount of dimethyl ether in product) / (molar amount of feed methanol) x 100 % and;

[0379] Selectivity % for C2 to C4 olefins = (2 x molar amount of C2 olefin in product + 3 x molar amount of C3 olefin in product + 4 x molar amount of C4 olefin in product) / (molar amount of methanol feed - molar amount of methanol in product - 2 x molar amount of dimethyl ether in product) x 100 %.

[0380] Selectivity of aromatic hydrocarbons % = (6 x molar amount of benzene in product + 7 x molar amount of toluene in product + 8 x molar amount of xylene in product) / (molar amount of methanol feed - molar amount of methanol in product - 2 x molar amount of dimethyl ether in product) x 100 %.

[0381] In the following examples and comparative examples, the reaction products of p-xylene were qualitatively analyzed by gas chromatography-mass spectrometry (GC-MS), and the substrate conversion rates of 2,5-methylfuran and / or 2,5-hexanedione and the yield of the reaction products of pX were analyzed by gas chromatography (GC). The gas chromatography-mass spectrometer was an Agilent 7890A from Agilent, USA; the chromatography column was an HP-5 non-polar capillary column (30 m, 0.53 mm); the gas chromatographer was an Agilent 7890B; the detector was a hydrogen flame ionization detector (FID); and the chromatography column was an SE-54 capillary column (30 m, 0.53 mm).

[0382] In the following examples and comparative examples, the formula for the conversion rate of 2,5-dimethylfuran (or 2,5-hexanedion) is as follows:

[0383] Conversion rate % of 2,5-dimethylfuran (and / or 2,5-hexanedion) = (Molar amount of 2,5-dimethylfuran (and / or 2,5-hexanedion) participating in the reaction) / (Molar amount of reaction substrate of 2,5-dimethylfuran (and / or 2,5-hexanedion)) x 100 %.

[0384] In this application, the formula for calculating the product yield of p-xylene (pX) is as follows:

[0385] % Product yield of pX = (Molar amount of pX produced by the reaction) / (Molar amount of reaction substrate of 2,5-dimethylfuran (and / or 2,5-hexanedion)) x 100 %.

[0386] In this application, the formula for calculating the product selectivity of p-xylene is as follows:

[0387] Product selectivity of pX % = (Molar amount of pX produced by reaction) / (Molar amount of 2,5-dimethylfuran (and / or 2,5-hexanedion) reacted) x 100 %.

[0388] Example II-1

[0389] n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to 2,5-dimethylfuran (DMF) of 20 and a mass ratio of DMF to catalyst of 1. The reaction temperature was 240 °C, and the reaction time was 24 hours. 1.0 g of SCM-36 zeolite prepared in Example I-1, 1.0 g of DMF, and 20 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on gas phase analysis of the reaction solution, the conversion rate of DMF was 86%, the pX selectivity was 94%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0390] Example II-2

[0391] n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to DMF of 20 and a mass ratio of DMF to catalyst of 1. The reaction temperature was 240 °C, and the reaction time was 24 hours. 1.0 g of SCM-36 zeolite prepared in Example I-2, 1.0 g of DMF, and 20 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on gas phase analysis of the reaction solution, the conversion rate of DMF was 90%, the pX selectivity was 94%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0392] Example II-3

[0393] n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to DMF of 20 and a mass ratio of DMF to catalyst of 1. The reaction temperature was 240 °C, and the reaction time was 24 hours. 1.0 g of SCM-36 zeolite prepared in Example I-3, 1.0 g of DMF, and 20 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 86%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0394] Example II-4

[0395] n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to DMF of 20 and a mass ratio of DMF to catalyst of 1. The reaction temperature was 240 °C, and the reaction time was 24 hours. 1.0 g of SCM-36 zeolite prepared in Example I-4, 1.0 g of DMF, and 20 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on gas phase analysis of the reaction solution, the conversion rate of DMF was 92%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0396] Example II-5

[0397] In this example, n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to DMF of 20 and a mass ratio of DMF to catalyst of 1.5. The reaction temperature was 250 °C, and the reaction time was 30 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1.5 g of DMF, and 30 g of n-heptane were placed in an autoclave under stirring, and 3.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 30 hours under conditions of 250 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 88%, the pX selectivity was 96%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0398] Example II-6

[0399] In this example, n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to 2,5-hexanedione (HDO) of 20 and a mass ratio of HDO to catalyst of 1. The reaction temperature was 230 °C, and the reaction time was 20 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1 g of HDO, and 20 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 20 hours under conditions of 230 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of HDO was 86%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0400] Example II-7

[0401] In this example, n-hexane was used as the reaction solvent, with a mass ratio of n-hexane to DMF of 30 and a mass ratio of DMF to catalyst of 2. The reaction temperature was 260 °C, and the reaction time was 24 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 2.0 g of DMF, and 60 g of n-hexane were placed in an autoclave under stirring, and 4.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 260 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 83%, the pX selectivity was 94%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0402] Example II-8

[0403] In this example, n-hexane was used as the reaction solvent, with a mass ratio of n-hexane to DMF of 20 and a mass ratio of DMF to catalyst of 1.5. The reaction temperature was 240 °C, and the reaction time was 30 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1.5 g of DMF, and 30 g of n-hexane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 30 hours under conditions of 240 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 88%, the pX selectivity was 93%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0404] Example II-9

[0405] In this example, γ-valerolactone was used as the reaction solvent, with a mass ratio of γ-valerolactone to HDO of 15 and a mass ratio of HDO to catalyst of 2. The reaction temperature was 270 °C, and the reaction time was 28 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 2 g of HDO, and 30 g of γ-valerolactone were placed in an autoclave under stirring, and 3.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 28 hours under conditions of 270 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of HDO was 89%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0406] Example II-10

[0407] In this example, γ-valerolactone was used as the reaction solvent, with a mass ratio of γ-valerolactone to DMF of 30 and a mass ratio of DMF to catalyst of 3. The reaction temperature was 270 °C, and the reaction time was 32 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 3.0 g of DMF, and 90 g of γ-valerolactone were placed in an autoclave under stirring, and 4.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 32 hours under conditions of 270 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 85%, the pX selectivity was 94%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0408] Example II-11

[0409] In this example, toluene was used as the reaction solvent, with a mass ratio of toluene to HDO of 22 and a mass ratio of HDO to catalyst of 1. The reaction temperature was 250 °C, and the reaction time was 18 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1 g of HDO, and 22 g of toluene were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 18 hours under conditions of 250 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of HDO was 93%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0410] Example II-12

[0411] In this example, toluene was used as the reaction solvent, with a mass ratio of toluene to HDO of 25 and a mass ratio of HDO to catalyst of 1.5. The reaction temperature was 260 °C, and the reaction time was 24 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1.5 g of HDO, and 37.5 g of toluene were placed in an autoclave under stirring, and 4.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 260 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of HDO was 90%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0412] Example II-13

[0413] In this example, cyclohexane was used as the reaction solvent, with a mass ratio of cyclohexane to DMF of 30 and a mass ratio of DMF to catalyst of 2. The reaction temperature was 250 °C, and the reaction time was 40 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 2.0 g of DMF, and 60 g of cyclohexane were placed in an autoclave under stirring, and 4.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 40 hours under conditions of 250 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of DMF was 86%, the pX selectivity was 96%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0414] Example II-14

[0415] In this example, cyclohexane was used as the reaction solvent, with a mass ratio of cyclohexane to HDO of 20 and a mass ratio of HDO to catalyst of 2. The reaction temperature was 255 °C, and the reaction time was 38 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 2.0 g of HDO, and 40.0 g of cyclohexane were placed in an autoclave under stirring, and 4.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 38 hours under conditions of 255 °C. Based on the gas phase analysis of the reaction solution, the conversion rate of HDO was 87%, the pX selectivity was 95%, and the selectivity for key impurities in polyalkylbenzene was less than 1%.

[0416] To describe the reaction conditions and results of Examples II-1 to II-14 above more intuitively, various parameters and results are listed in Table II-1.

[0417] [Table II-1 Reaction conditions and results of Examples II-1 to II-14]

[0418]

[0419] Example II-15

[0420] n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to DMF of 20 and a mass ratio of DMF to catalyst of 1. The reaction temperature was 240 °C, and the reaction time was 24 hours. 1.0 g of the SCM-36 zeolite catalyst prepared in Example I-1, 1.0 g of DMF, and 20.0 g of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. The conversion rate of DMF and pX selectivity were calculated based on gas phase analysis of the reaction solution. The catalyst used was washed and dried before proceeding with the next reaction, and the reaction was repeated a total of four times. The results are shown in Fig. 11. As a result, after 4 reactions, the conversion rate of DMF remained above 82%, the pX selectivity remained above 92%, and the selectivity of key impurities of polyalkylbenzene was less than 1%, indicating that the SCM-36 zeolite has good cycling stability.

[0421] Example II-16

[0422] 1) Preparation of SCM-36 Zeolite

[0423] Tests were performed with reference to Example I-1, except that the reactants and material ratios (molar ratios) used were as follows:

[0424] Al2O3 / SiO2=0.017

[0425] Tetramethylammonium hydroxide (A) / SiO2=0.20

[0426] n-octyltrimethylammonium chloride (B) / SiO2=0.25

[0427] NaOH / SiO2=0.20

[0428] H2O / SiO2=30 and;

[0429] After uniform mixing, the mixture was placed in a stainless steel reactor and crystallized at 155 °C for 8 days. Once crystallization was complete, the product was filtered, washed, dried in an oven at 120 °C for 6 hours, and calcined in air at 550 °C for 8 hours to obtain zeolite.

[0430] XRD spectrum data of the dried sample is shown in Table II-2, and the SEM image of the sample is similar to that shown in Figure 2.

[0431] [Table II-2 XRD Spectrum Data of Zeolite Produced in Example II-16]

[0432]

[0433] The generated calcination product has a specific surface area of ​​372 m² 2 / g, external specific surface area is 149 m² 2 / g, total pore volume is 0.74 cm³ 3 / g, and the micropore volume is 0.09 cm³ 3 / g. The sample is in the form of nanoflakes and has a crystal thickness of approximately 12 nanometers. The calcined sample has a SiO2 / Al2O3 ratio of 61.5 (molar ratio) as measured using the inductively coupled plasma atomic emission spectrometer (ICP).

[0434] The ammonia temperature programmed desorption (NH3-TPD) spectrum of the generated sample is shown in Fig. 12. As a result, the total acid content is 470 μmol·g -1 The weak acid content is 47%. The infrared spectrum of pyridine adsorption is shown in Fig. 13, and the Lewis / Bronstead acid ratio was analyzed and measured to be 0.4.

[0435] 2) Preparation of p-xylene

[0436] n-heptane was used as the reaction solvent. 1.0 g of the SCM-36 zeolite prepared above, 1.0 g of DMF, and 20 ml of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on the gas phase analysis of the reaction mixture, the conversion rate of DMF was calculated to be 93%, the pX selectivity was 90%, and the selectivity for key impurities in polyalkylbenzene was 3%.

[0437] Comparative Example II-1

[0438] The literature (Microporous and Mesoporous Materials, 2018, 263, 11-20) reported the production of AlPO-17 zeolite. Phosphoric acid, aluminum isopropoxide, cyclohexylamine, and deionized water were uniformly mixed to form a gel according to a ratio of 1 P2O5: 0.9 Al2O3: 1 CHA (cyclohexylamine): 50 H2O. Subsequently, hydrothermal crystallization was performed at 190 °C for 120 hours, followed by washing, drying, and calcination in air at 550 °C for 5 hours to produce AlPO-17 zeolite. The sample was 262 μmol·g -1 The weak acid content was 93%, and the Lewis / Bronstead acid ratio was 4.2.

[0439] n-heptane was used as the reaction solvent. 1.0 g of the catalyst produced above, 1.0 g of DMF, and 20 ml of n-heptane were placed in an autoclave under stirring, and 2.0 MPa of ethylene was added. The temperature was raised to a preset temperature using a temperature-programmed heating jacket, and then stirred using magnetic stirring. The reaction was carried out for 24 hours under conditions of 240 °C. Based on the gas phase analysis of the reaction mixture, the conversion rate of DMF was calculated to be 67%, and the pX selectivity was 72%.

[0440] Preferred embodiments of the present application have been described in detail as above. However, the present application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present application, a number of simple modifications may be made to the technical solution of the present application, all of which fall within the scope of protection of the present application.

[0441] Furthermore, it should be noted that each of the specific technical features described in the specific embodiments above may be combined in any suitable manner in the absence of contradiction. To avoid unnecessary repetition, the present application will not separately describe the various possible combinations.

[0442] Furthermore, various other embodiments of the present application may also be optionally combined. Various other embodiments of the present application shall also be deemed to be as disclosed in the present application, provided that they do not infringe upon the technical spirit of the present application.

Claims

Claim 1 A silicon-aluminum zeolite, wherein the silicon / aluminum ratio n is n≥5, or n is in the range of 5 to 80, or in the range of 10 to 65, and the X-ray diffraction spectrum of the zeolite exhibits the relative intensity characteristics of the diffraction peaks shown in the table below: . Claim 2 In claim 1, the X-ray diffraction spectrum of the zeolite also exhibits the relative intensity characteristics of the diffraction peaks shown in any one of the columns of the table below, silicon-aluminum zeolite: . Claim 3 In paragraph 2, the X-ray diffraction spectrum of the zeolite also exhibits the relative intensity characteristics of the diffraction peaks shown in any one of the columns of the table below, silicon-aluminum zeolite: Claim 4 In claim 1, a silicon-aluminum zeolite having at least one of the following features: the specific surface area is 300 m² 2 / g to 700 m 2 / g, or 300 m 2 / g to 600 m 2 / g, or 350 m 2 / g to 500 m 2 / g and the external specific surface area is 50 m² 2 / g to 300 m 2 / g, or 80 m 2 / g to 250 m 2 / g, or 100 m 2 / g to 220 m 2 / g and the total pore volume is 0.20 cm³ 3 / g to 1.50 cm 3 / g, or 0.40 cm 3 / g to 1.20 cm 3 / g, or 0.5 cm 3 / g to 1.0 cm 3 / g and the micropore volume is 0.05 cm³ 3 / g to 0.35 cm 3 / g, or 0.08 cm 3 / g to 0.30 cm 3 / g, or 0.09 cm 3 / g to 0.25 cm 3 / g; the total acid content is 400 μmol·g -1 to 1200 μmol·g -1 , or 500 μmol·g -1 to 1000 μmol·g -1 And, where the weak acid content is 40% or more, or 45% to 90%; and the Lewis / Bronstead acid ratio is 0.1 to 3.8, or 0.4 to 3.

5. Claim 5 In claim 1, the zeolite is a silicon-aluminum zeolite having a nano-flake crystal form with a crystal thickness of less than 30 nanometers, or 5 nanometers to 25 nanometers, or 7 nanometers to 20 nanometers. Claim 6 The silicon-aluminum zeolite according to claim 1, wherein the zeolite further comprises at least one element M selected from the group consisting of titanium, boron, zirconium, tin, and iron; and wherein the total content of the element M in the zeolite is 3 mol% or less based on the oxide and based on the total amount of Si, Al, and element M. Claim 7 A method for producing a silicon-aluminum zeolite according to any one of claims 1 to 6, comprising: 1) a step of crystallizing a mixture comprising a silicon source, an aluminum source, an organic structure inducer (A), an organic structure inducer (B), an alkali source, and water to obtain a zeolite; and 2) optionally, a step of calcining the zeolite obtained in step 1), wherein the organic structure inducer (A) is selected from tetramethylammonium compounds, and the organic structure inducer (B) is C 6-16 A method for preparing a silicon-aluminum zeolite selected from an alkylpyridinium compound, an n-octyltrimethylammonium compound, or a combination thereof. Claim 8 A method for producing a silicon-aluminum zeolite according to claim 7, wherein in the mixture of step 1), the molar ratio of the silicon source (calculated based on SiO2) to the aluminum source (calculated based on Al2O3) to the organic structure inducer (A) to the organic structure inducer (B) to the alkali source to water is 1:(0.01-0.20):(0.05-0.80):(0.05-0.80):(0.05-0.50):(8-80), or 1:(0.01-0.10):(0.08-0.65):(0.08-0.65):(0.08-0.45):(10-70), or 1:(0.02-0.07):(0.10-0.50):(0.10-0.50):(0.10-0.40):(12-60). Claim 9 A method for producing silicon-aluminum zeolite according to claim 7, wherein the crystallization temperature of step 1) is 120 ℃ to 200 ℃, or 130 ℃ to 190 ℃, or 140 ℃ to 180 ℃; and the crystallization time is 1 day to 15 days, or 2 days to 12 days, or 3 days to 9 days. Claim 10 In claim 7, the organic structure inducer (A) is selected from the group consisting of tetramethylammonium hydroxide, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, or combinations thereof; and / or the organic structure guide (B) is selected from the group consisting of hexadecylpyridine bromide, tetradecylpyridine bromide, dodecylpyridine bromide, decylpyridine bromide, hexadecylpyridine chloride, tetradecylpyridine chloride, hexadecylpyridine hydroxide, n-octyltrimethylammonium chloride, n-octyltrimethylammonium bromide, n-octyltrimethylammonium hydroxide, or combinations thereof, or is selected from the group consisting of hexadecylpyridine bromide, tetradecylpyridine bromide, dodecylpyridine bromide, hexadecylpyridine chloride, hexadecylpyridine hydroxide, n-octyltrimethylammonium chloride, n-octyltrimethylammonium bromide, or combinations thereof, for preparing a silicon-aluminum zeolite method. Claim 11 A method for preparing a silicon-aluminum zeolite according to claim 7, wherein the silicon source is selected from the group consisting of silicon acid, silica gel, silica sol, tetraethyl silicate, sodium silicate, or a combination thereof; the aluminum source is selected from the group consisting of aluminum hydroxide, aluminum oxide, aluminate, aluminum salt, and tetraalkoxyaluminum, or a combination thereof; and / or the alkali source is selected from the group consisting of an inorganic alkali having an alkali metal as a cation, an inorganic alkali having an alkaline earth metal as a cation, or a combination thereof. Claim 12 A method for producing a silicon-aluminum zeolite according to claim 7, wherein the mixture according to step 1) further comprises a source of element M selected from the group consisting of titanium, boron, zirconium, tin, iron, or combinations thereof, and the molar ratio of the silicon source to the source of element M is 1:(0.002-0.10) or 1:(0.005-0.05) when calculated based on the oxide. Claim 13 A zeolite composition comprising a silicon-aluminum zeolite and a binder according to any one of claims 1 to 6. Claim 14 A silicon-aluminum zeolite used as an adsorbent, catalyst, or catalyst carrier in any one of claims 1 to 6. Claim 15 A method for producing p-xylene, comprising the step of reacting a raw material comprising 2,5-dimethylfuran, 2,5-hexanedione, or a combination thereof with ethylene in the presence of a catalyst comprising or made of a silicon-aluminum zeolite according to any one of claims 1 to 6. Claim 16 A method for producing p-xylene according to claim 15, having at least one of the following features: the reaction is carried out in the presence of an organic solvent selected from the group consisting of n-hexane, n-heptane, γ-valerolactone, tetrahydrofuran, toluene, cyclohexane, or combinations thereof; the mass ratio of the raw material to the catalyst is 0.6-30:1, or 1.0-10:1; and the mass ratio of the organic solvent to the raw material is 8-60:1, or 10-30:

1. Claim 17 In claim 15, the conditions of the reaction comprises a method for producing p-xylene, wherein the reaction temperature is 160 ℃ to 340 ℃ or 220 ℃ to 270 ℃; the reaction time is 6 hours to 64 hours or 8 hours to 48 hours; and the reaction pressure is 1 MPa to 8 MPa or 2 MPa to 4 MPa.

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