A spherical ssz-13 molecular sieve, its preparation method and application

Abstract

The application discloses a kind of spherical SSZ-13 molecular sieve and its preparation method and application.The spherical SSZ-13 molecular sieve is aggregated into spherical morphology by nanocrystalline grain, size is 0.2~5.0 μm, SiO2 / Al2O3 molar ratio is 29.0~80.0, wherein the size of nanocrystalline grain that constitutes spherical particle is 30~100 nm.The spherical SSZ-13 molecular sieve of the application has special excellent performance as methanol conversion catalyst.

Description

Technical Field

[0001] This invention belongs to the field of molecular sieve technology, specifically relating to a spherical SSZ-13 molecular sieve, its preparation method, and its application. Background Technology

[0002] In industry, subtle differences in the structure of molecular sieve materials lead to significant variations in their catalytic and adsorption properties. SSZ-13 possesses a CHA topology, consisting of AlO4 and SiO4 tetrahedra connected end-to-end by oxygen atoms, arranged in an orderly fashion into an ellipsoidal cage (0.73 nm × 1.2 nm) with an eight-membered ring structure and a three-dimensional intersecting channel structure with a pore size of 0.38 nm × 0.38 nm. It is used in the removal of NO from automobile exhaust. x It has shown excellent performance in fields such as (NH3-SCR), methanol conversion (MTH) and CO2 adsorption separation, and has been widely used in many industrial catalytic processes in recent years.

[0003] Currently, SSZ-13 molecular sieves generally utilize N,N,N-trimethyladamantane ammonium (TMAda) + ), benzyltrimethylammonium (BTMA) + SSZ-13 was synthesized via a hydrothermal method using N-alkyl-1,4-diazabicyclooctane cations, polycyclic alkylammonium cations, N,N-dimethylpiperidine, and choline chloride as template agents.

[0004] Patent CN112429749A discloses a small-crystal, high-porosity CHA zeolite molecular sieve, its synthesis method, and its catalytic application. The CHA zeolite molecular sieve is synthesized using a composite organic structure directing agent formed by a quaternary ammonium onion compound containing tetrahydronaphthalene or decahydronaphthalene groups and an N,N,N-dimethylethylcyclohexyl quaternary ammonium onion compound, with an average crystal diameter ≤500 nm. Patent CN113351244A discloses a CHA molecular sieve, its preparation method, a denitrification catalyst, its preparation method, and its application. The CHA molecular sieve is in the form of nanosheets with a thickness of 80–120 nm, exhibiting a small size that shortens the reaction channels of the molecular sieve, resulting in high activity as a denitrification catalyst.

[0005] SSZ-13 molecular sieves are microporous molecular sieves. The large crystal size of these sieves can significantly hinder the diffusion of reactants and products in catalytic reactions, especially methanol conversion, leading to carbon buildup and affecting catalyst lifespan. Therefore, it is essential to develop a nano-SSZ-13 molecular sieve that combines the high activity of nano-zeolites with the advantages of easily separating micron-sized crystal products from the synthesis and reaction systems, while also exhibiting tunable acidity and good catalytic performance. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a spherical SSZ-13 molecular sieve, its preparation method and application. The spherical SSZ-13 molecular sieve, as a methanol conversion catalyst, has special and excellent catalytic performance.

[0007] The first aspect of the present invention provides a spherical SSZ-13 molecular sieve, the morphology of which is spherical or ellipsoidal particles formed by the aggregation of nanocrystals, the particle size being 0.2 to 5.0 μm, and the SiO2 / Al2O3 molar ratio of the spherical SSZ-13 molecular sieve being 29.0 to 80.0, preferably 30.0 to 70.0.

[0008] Furthermore, the spherical SSZ-13 molecular sieve has a particle size of 0.25–4.50 μm.

[0009] Furthermore, the nanocrystals that make up the spherical or ellipsoidal particles have a grain size of 30–100 nm, preferably 35–90 nm.

[0010] Furthermore, the total specific surface area of ​​the spherical SSZ-13 molecular sieve is not less than 500 m². 2 / gram, preferably 500-850 meters 2 / gram; external specific surface area not less than 50 m² 2 / gram, preferably 50-120 meters 2 / gram.

[0011] Furthermore, the total pore volume of the SSZ-13 molecular sieve is not less than 0.30 cm³. 3 / gram, preferably 0.30 to 0.75 cm 3 / gram; micropore volume not less than 0.20 cm³ 3 / gram, preferably 0.20 to 0.30 cm 3 / gram.

[0012] Furthermore, after the spherical SSZ-13 molecular sieve undergoes ammonium ion exchange treatment to form the hydrogen form, the total acid content is not less than 600 μmol / g, preferably 600–1500 μmol / g; the strong acid content is not less than 300 μmol / g, preferably 300–800 μmol / g.

[0013] A second aspect of this invention provides a method for preparing spherical SSZ-13 molecular sieves, comprising the following steps:

[0014] A silicon source, an aluminum source, sodium hydroxide, organic structure directing agent a, organic structure directing agent b, and water are mixed and crystallized to obtain the spherical SSZ-13 molecular sieve; and optionally, the spherical SSZ-13 molecular sieve is obtained by calcination.

[0015] Furthermore, the added silicon source (SiO2), aluminum source (Al2O3), sodium hydroxide, organic structure directing agent a (SDA1), organic structure directing agent b (SDA2), and water are in a molar ratio of SiO2:Al2O3:NaOH:SDA1:SDA2:H2O = 1:0.013~0.034:0.10~0.22:0.05~0.20:0.05~0.15:12~50.

[0016] Furthermore, the added silicon source (SiO2), aluminum source (Al2O3), sodium hydroxide, organic structure directing agent a (SDA1), organic structure directing agent b (SDA2), and water are in a molar ratio of SiO2:Al2O3:NaOH:SDA1:SDA2:H2O = 1:0.015~0.033:0.12~0.20:0.10~0.20:0.05~0.15:15~40.

[0017] Furthermore, the silicon source is silica sol; the aluminum source is sodium aluminate.

[0018] Furthermore, the sodium aluminate contains 38% to 43% Al2O3 by weight and 30% to 33% Na2O by weight.

[0019] Furthermore, the organic structure directing agent a (SDA1) is methyltriethylammonium hydroxide; and the organic structure directing agent b (SDA2) is N,N,N-trimethyladamantaneammonium.

[0020] Furthermore, the crystallization conditions of the reaction mixture are crystallization at 130–180°C for 1.75–6.0 days, preferably at 140–170°C for 2.0–5.0 days.

[0021] Furthermore, the crystallization process of the reaction mixture is a dynamic crystallization by rotation or stirring, with a rotation or stirring speed of 10 to 300 rpm, preferably 20 to 150 rpm.

[0022] Furthermore, no seed crystals need to be added during the crystallization process of the molecular sieve.

[0023] Furthermore, the yield of the molecular sieve product exceeds 85%.

[0024] Furthermore, the crystallization can be carried out in any manner conventionally known in the art, such as by mixing the silicon source, aluminum source, sodium hydroxide, organic structure directing agent a, organic structure directing agent b and water in a predetermined ratio, and then heating the resulting mixture under crystallization conditions.

[0025] Furthermore, after the crystallization step, the obtained mixture can be processed to obtain the product by any conventionally known separation method. Examples of such separation methods include filtering, washing, and drying the obtained mixture. Here, the filtration, washing, and drying can be performed in any manner conventionally known in the art. Specifically, for example, the filtration can be performed by simply vacuum filtering the obtained product mixture. For example, washing can be performed using deionized water and / or ethanol. For example, the drying temperature can be 40–250°C, preferably 60–150°C, and the drying time can be 8–30 hours, preferably 10–20 hours. This drying can be carried out under normal pressure or under reduced pressure.

[0026] Furthermore, the SSZ-13 molecular sieve obtained after the crystallization step can be further processed by calcination to obtain Na-SSZ-13 molecular sieve. The calcination can be carried out in any manner conventionally known in the art, for example, the calcination temperature is generally 300–800°C, preferably 400–650°C, and the calcination time is generally 1–10 hours, preferably 3–6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0027] Furthermore, before use, the Na-SSZ-13 molecular sieve is converted to the H-form using ammonium chloride solution. The operation method is the conventional ammonium exchange method, and the specific steps are as follows: Na-SSZ-13 and ammonium salt solution are ion exchanged at a solid-liquid mass ratio of 1:5 to 1:20 at 30 to 80°C for 1 to 8 hours. After separating the solid, the exchange is repeated 0 to 2 times in the above manner. After filtration and washing, the filter cake is dried overnight in an oven at 40 to 120°C and then calcined at 400 to 650°C for 1 to 12 hours to obtain the hydrogen form SSZ-13 molecular sieve.

[0028] Furthermore, the ammonium salt used in the exchange is selected from at least one of ammonium chloride, ammonium nitrate, ammonium carbonate, and ammonium sulfate; the concentration of ammonium ions in the ammonium salt solution is 0.1–1 mol / L.

[0029] Furthermore, the total acid content of the hydrogen-form SSZ-13 molecular sieve is not less than 600 μmol / g, preferably 600–1500 μmol / g; the strong acid content is not less than 300 μmol / g, preferably 300–800 μmol / g.

[0030] A third aspect of the present invention provides a spherical SSZ-13 molecular sieve prepared according to any of the preparation methods described in the second aspect above.

[0031] Furthermore, the SSZ-13 molecular sieve has a morphology of spherical or ellipsoidal particles formed by the aggregation of nanocrystals, with a particle size of 0.2–5.0 μm, preferably 0.25–4.50 μm; the SiO2 / Al2O3 molar ratio of the spherical SSZ-13 molecular sieve is 29.0–80.0, preferably 30.0–70.0.

[0032] Furthermore, the nanocrystals that make up the spherical or ellipsoidal particles have a grain size of 30–100 nm, preferably 35–90 nm.

[0033] A fourth aspect of the present invention also provides a spherical SSZ-13 molecular sieve composition comprising a spherical SSZ-13 molecular sieve prepared according to any of the methods described in the first aspect or according to any of the methods described in the second aspect, and a binder.

[0034] The fifth aspect of the present invention also provides the use of spherical SSZ-13 molecular sieves prepared according to any of the first aspects described above, or spherical SSZ-13 molecular sieves prepared according to any of the preparation methods described in the second aspect described above, or spherical SSZ-13 molecular sieve compositions described in the third aspect described above as catalysts in organic matter conversion.

[0035] Furthermore, spherical SSZ-13 molecular sieves were used as catalysts for methanol conversion reactions.

[0036] Furthermore, the process conditions for the reaction are: reaction temperature 350–500°C, and mass hourly space velocity (HHSV) 0.5–8 h⁻¹. -1 Preferably 0.75–6h -1 .

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] The spherical SSZ-13 molecular sieve of the present invention consists of spherical or ellipsoidal particles formed by the aggregation of nanocrystals, with a particle size of 0.3 to 5.0 μm. The nanocrystals that make up the spherical or ellipsoidal particles have a size of 30 to 100 nm. The SiO2 / Al2O3 molar ratio of the SSZ-13 molecular sieve is 29 to 80.

[0039] This invention utilizes a special aluminum source and a dual-organic structure directing agent to prepare spherical SSZ-13 molecular sieves via one-step crystallization. No seed crystals are required during the preparation process. The synthesized spherical SSZ-13 molecular sieves exhibit high yield, pure crystalline phase, high acid content, and a high concentration of strong acids. The synthesized spherical SSZ-13 molecular sieves demonstrate exceptional performance as a methanol conversion catalyst. Attached Figure Description

[0040] Figure 1 The X-ray diffraction (XRD) pattern of the sample in Example 1;

[0041] Figure 2 The image shown is a scanning electron microscope (SEM) image of the sample in Example 1.

[0042] Figure 3 The diagram shows the reaction performance of the catalyst in Example 1;

[0043] Figure 4 The X-ray diffraction (XRD) pattern of the sample in Example 2;

[0044] Figure 5 The image shown is a scanning electron microscope (SEM) image of the sample in Example 2.

[0045] Figure 6 The reaction performance diagram of the catalyst in Example 2 is shown.

[0046] Figure 7 The X-ray diffraction (XRD) pattern of the sample in Example 3;

[0047] Figure 8 The image shown is a scanning electron microscope (SEM) image of the sample in Example 3.

[0048] Figure 9 The X-ray diffraction (XRD) pattern of the sample in Example 4;

[0049] Figure 10 The image shown is a scanning electron microscope (SEM) image of the sample in Example 4.

[0050] Figure 11 The X-ray diffraction (XRD) pattern of the sample in Example 5;

[0051] Figure 12 The image shown is a scanning electron microscope (SEM) image of the sample in Example 5.

[0052] Figure 13 The X-ray diffraction (XRD) pattern of the sample in Comparative Example 1 is shown.

[0053] Figure 14 The X-ray diffraction (XRD) pattern of the sample in Comparative Example 2 is shown.

[0054] Figure 15 The X-ray diffraction (XRD) pattern of the sample in Comparative Example 3 is shown.

[0055] Figure 16 This is a scanning electron microscope (SEM) image of the sample in Comparative Example 4. Detailed Implementation

[0056] In the context of this specification, the structure of the molecular sieve is determined by X-ray diffraction (XRD), which is measured using an X-ray powder diffractometer with a Cu-Kα ray source and a nickel filter. Before sample testing, the crystallinity of the molecular sieve sample is observed using a scanning electron microscope (SEM) to confirm that the sample contains only one type of crystal, i.e., the molecular sieve sample is a pure phase. XRD testing is then performed to ensure that there are no interfering peaks from other crystals in the diffraction pattern.

[0057] In the context of this specification, including in the following examples and comparative examples, the X-ray powder diffractometer used for the molecular sieves is a Panalytical X-PERPRO type X-ray powder diffractometer, used to analyze the phase composition of the samples, and a CuKα ray source. Nickel filter, 2θ scanning range 2~50°, operating voltage 40KV, current 40mA, scanning rate 10° / min.

[0058] In the context of this specification, including in the following examples and comparative examples, the scanning electron microscope (SEM) used for the molecular sieves is an S-4800II field emission scanning electron microscope. The molecular sieves were observed using this SEM at a magnification of 40,000x. A randomly selected field of view was used to calculate the average sum of the crystal sizes in that field of view, and this operation was repeated 10 times. The average sum of the 10 averages was used as the crystal size, and the average size of the spherical clusters was calculated using the same method.

[0059] In the context of this specification, including in the following examples and comparative examples, the pore volume, specific surface area, and external specific surface area of ​​the molecular sieve were measured by the nitrogen physical adsorption-desorption method (BET method): the nitrogen physical adsorption-desorption isotherm of the molecular sieve was measured using a Micromeretic ASAP2020M physical adsorption instrument, and then calculated using the BET equation and t-plot equation. The experimental conditions for this molecular sieve were: measurement temperature -196°C; before measurement, the molecular sieve was heat-treated at 550°C in air for 6 hours, and then pretreated in vacuum at 350°C for 4 hours.

[0060] In the context of this specification, including in the following examples and comparative examples, the content of each element in the molecular sieve was determined by inductively coupled plasma atomic emission spectrometry (ICP) using a Varian 725-ES instrument. The analytical sample was dissolved in hydrofluoric acid before testing, and the content was expressed in moles.

[0061] In the context of this specification, including the following examples and comparative examples, the acid content of the molecular sieves was determined using an Altamira AMI-3300 instrument with NH3-TPD chemisorption-desorption curves. Before testing, the samples were activated at 550°C for 1 hour, ammonia was adsorbed at 100°C for 20 minutes, and then desorbed and detected at 100–600°C. By analyzing the Gaussian peak distribution, the acid content corresponding to desorption temperatures above 300°C was considered the acid content of strong acids.

[0062] In the context of this specification, including in the following examples and comparative examples, the yield of molecular sieves refers to the percentage of the mass of the calcined sample relative to the sum of the masses of SiO2 and Al2O3 contained in the raw material.

[0063] In the context of this specification, including in the following examples and comparative examples, the catalyst carries out a methanol conversion reaction:

[0064] Methanol conversion rate % = (molar amount of feed methanol - molar amount of product methanol - 2 × molar amount of dimethyl ether in the discharge mixture) / (molar amount of feed methanol) × 100%.

[0065] When the methanol conversion rate is >99%, the methanol is considered to be completely converted and the catalyst is not deactivated; when the methanol conversion rate is <80%, the catalyst is considered to be completely deactivated.

[0066] C2 olefin selectivity % = (2 × molar amount of C2 olefin in product) / (molar amount of feed methanol - molar amount of methanol in product - 2 × molar amount of dimethyl ether in discharge mixture) × 100%.

[0067] Similarly, selectivity was obtained for ethane, propylene, propane, butene, butane, and hydrocarbons with more than 5 carbon atoms in the product.

[0068] The initial stage of the reaction is the period from 0 to 30 minutes after the start of the reaction; when the methanol conversion rate is less than 98%, the catalyst is considered to have begun to deactivate.

[0069] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to these embodiments.

[0070] Example 1

[0071] 25.86 g of deionized water, 1.333 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.267 g of sodium hydroxide, 8.47 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 6.68 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 23.86 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0072] SiO2 / Al2O3 = 30;

[0073] NaOH / SiO2 = 0.12;

[0074] Methyltriethylammonium hydroxide / SiO2 = 0.10;

[0075] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.05;

[0076] H2O / SiO2 = 18.

[0077] The mixture was placed in a stainless steel reactor and heated to 160°C at 20 rpm for 3 days for crystallization. After crystallization, the mixture was filtered, washed, dried overnight in a 100°C oven, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product is shown below. Figure 1 The sample shown is an SSZ-13 molecular sieve with a CHA structure and a yield of 89 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 30.3 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is shown below. Figure 2 As shown, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters. The nanoparticles have a size of 40 nm, and the spherical clusters have a size of 0.3 μm. The sample has a specific surface area of ​​768 m². 2 / gram, with an external specific surface area of ​​55 m² measured by the BET method. 2 / g; Total pore volume 0.45cm 3 / gram, micropore volume is 0.25 cm³ 3 / gram.

[0078] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 65℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 1136 μmol / g and the strong acid content was 379 μmol / g by NH3-TPD.

[0079] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particles, which were then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 375℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity (WHSV) 2.5 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph, such as... Figure 3 The figures show catalyst activity and product selectivity; the selectivity of propane in the products during the initial stage of the reaction is the highest, exceeding 70%; the diene selectivity of ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 84%.

[0080] Example 2

[0081] 14.88 g of deionized water, 0.672 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.471 g of sodium hydroxide, 9.61 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 8.09 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 18.05 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0082] SiO2 / Al2O3 = 45;

[0083] NaOH / SiO2 = 0.15;

[0084] Methyltriethylammonium hydroxide / SiO2 = 0.15;

[0085] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.08;

[0086] H2O / SiO2 = 18.

[0087] The mixture was placed in a stainless steel reactor and heated at 155°C and 20 rpm for 3.5 days to crystallize. After crystallization, the mixture was filtered, washed, dried overnight in an oven at 100°C, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product is shown below. Figure 4 The sample shown is an SSZ-13 molecular sieve with a CHA structure and a yield of 92 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 44.6 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is shown below. Figure 5 As shown, the crystals exhibit a morphology of nanoparticles aggregated into ellipsoidal clusters. The nanoparticles have a size of 45 nm, and the ellipsoidal clusters have a size of 0.6 μm. The sample has a specific surface area of ​​773 m². 2 / gram, with an external specific surface area of ​​79 m² measured by the BET method. 2 / g; Total pore volume 0.62cm 3 / gram, micropore volume is 0.27 cm³ 3 / gram.

[0088] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 65℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 896 μmol / g and the strong acid content was 362 μmol / g by NH3-TPD.

[0089] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particles, which were then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity (WHSV) 1.5 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph, such as... Figure 6 The figures show catalyst activity and product selectivity; propane selectivity was highest at over 50% in the initial stage of the reaction; and the diene selectivity of ethylene and propylene in the products within 30 minutes before catalyst deactivation was 83%.

[0090] Example 3

[0091] 11.96 g of deionized water, 0.388 g of sodium aluminate (containing 42.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.548 g of sodium hydroxide, 6.21 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 8.17 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 14.59 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0092] SiO2 / Al2O3 = 60;

[0093] NaOH / SiO2 = 0.18;

[0094] Methyltriethylammonium hydroxide / SiO2 = 0.12;

[0095] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.10;

[0096] H2O / SiO2 = 18.

[0097] The mixture was placed in a stainless steel reactor and heated at 160°C and 20 rpm for 2.5 days to crystallize. After crystallization, the mixture was filtered, washed, dried overnight in an oven at 100°C, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product is shown below. Figure 7 The sample shown is an SSZ-13 molecular sieve with a CHA structure and a yield of 88 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 61.2 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is shown below. Figure 8 As shown, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters, with nanoparticles measuring 40 nm in size and spherical clusters measuring 0.6 μm in size. The sample has a specific surface area of ​​760 m². 2 / gram, with an external specific surface area of ​​64 m² measured by the BET method. 2 / g; Total pore volume 0.60cm 3 / gram, micropore volume is 0.21 cm³ 3 / gram.

[0098] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 65℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 768 μmol / g and the strong acid content was 316 μmol / g by NH3-TPD.

[0099] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of the 20-40 mesh particle size fraction, which was then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity 2.0 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 3 Similarly, the selectivity for propane in the products during the initial stage of the reaction is higher than 60%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 82%.

[0100] Example 4

[0101] 210.69 g of deionized water, 26.555 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 33 wt% Na₂O), 14.665 g of sodium hydroxide, 236.09 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 319.48 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 475.30 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0102] SiO2 / Al2O3 = 30;

[0103] NaOH / SiO2 = 0.20;

[0104] Methyltriethylammonium hydroxide / SiO2 = 0.14;

[0105] N,N,N-trimethyladamantane ammonium / SiO2 = 0.12;

[0106] H2O / SiO2 = 16.

[0107] The mixture was placed in a stainless steel reactor and heated to crystallize at 160°C and 120 rpm for 4 days. After crystallization, the mixture was filtered, washed, dried overnight in an oven at 100°C, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product is shown below. Figure 9 The sample shown is an SSZ-13 molecular sieve with a CHA structure and a yield of 90 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 30.6 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is shown below. Figure 10 As shown, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters, with nanoparticles measuring 50 nm in size and spherical clusters measuring 0.5 μm in size. The sample has a specific surface area of ​​754 m². 2 / gram, with an external specific surface area of ​​58 m² measured by the BET method. 2 / g; Total pore volume 0.54cm 3 / gram, micropore volume is 0.25 cm³ 3 / gram.

[0108] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 1235 μmol / g and the strong acid content was 454 μmol / g by NH3-TPD.

[0109] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of the 20-40 mesh particle size fraction, which was then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 420℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity 1.0 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 6 Similarly, the selectivity for propane in the products during the initial stage of the reaction is above 70%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 83%.

[0110] Example 5

[0111] 35.73 g of deionized water, 13.834 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 2.767 g of sodium hydroxide, 140.57 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 208.05 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 247.62 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0112] SiO2 / Al2O3 = 30;

[0113] NaOH / SiO2 = 0.12;

[0114] Methyltriethylammonium hydroxide / SiO2 = 0.16;

[0115] N,N,N-trimethyladamantane ammonium / SiO2 = 0.15;

[0116] H2O / SiO2 = 15.

[0117] The mixture was placed in a stainless steel reactor and heated to crystallize at 160°C with a stirring speed of 80 rpm for 3 days. After crystallization, the mixture was filtered, washed, dried in an oven at 100°C overnight, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product is shown below. Figure 11 The sample shown is an SSZ-13 molecular sieve with a CHA structure and a yield of 88 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 30.2 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is shown below. Figure 12 As shown, the crystals exhibit a morphology of nanoparticles aggregated into ellipsoidal clusters. The size of the nanoparticles is 45 nm, and the size of the ellipsoidal clusters is 0.8 μm. The specific surface area of ​​the sample is 772 m². 2 / gram, with an external specific surface area of ​​85 m² measured by the BET method. 2 / g; Total pore volume 0.79cm 3 / gram, micropore volume is 0.27 cm³ 3 / gram.

[0118] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 1194 μmol / g and the strong acid content was 416 μmol / g by NH3-TPD.

[0119] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of the 20-40 mesh particle size fraction, which was then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 380℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity 1.0 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 6 Similarly, the selectivity of propane in the products during the initial stage of the reaction is higher than 60%; the diene selectivity of ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 84%.

[0120] Example 6

[0121] 389.48 g of deionized water, 9.382 g of sodium aluminate (containing 38.5 wt% Al2O3 and 30.6 wt% Na2O), 4.619 g of sodium hydroxide, 135.94 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 59.61 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 212.84 g of silica sol (containing 40.0 wt% SiO2) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0122] SiO2 / Al2O3 = 40;

[0123] NaOH / SiO2 = 0.14;

[0124] Methyltriethylammonium hydroxide / SiO2 = 0.18;

[0125] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.05;

[0126] H2O / SiO2 = 26.

[0127] The mixture was placed in a stainless steel reactor and heated to crystallize at 165°C and 100 rpm for 2.5 days. After crystallization, it was filtered, washed, dried in an oven at 100°C overnight, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product obtained was similar to... Figure 1 Similarly, the SSZ-13 molecular sieve has a CHA structure, with a yield of 90 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 39.8 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is similar to... Figure 2 Similarly, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters, with nanoparticles measuring 40 nm and spherical clusters measuring 1.4 μm. The sample has a specific surface area of ​​750 m². 2 / gram, with an external specific surface area of ​​67 m² measured by the BET method. 2 / g; Total pore volume 0.73cm 3 / gram, micropore volume is 0.26 cm³ 3 / gram.

[0128] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 903 μmol / g and the strong acid content was 416 μmol / g by NH3-TPD.

[0129] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particles, which were then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity (WHSV) 1.5 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 6 Similarly, the selectivity of propane in the products during the initial stage of the reaction is higher than 60%; the diene selectivity of ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 80%.

[0130] Example 7

[0131] A mixture was prepared by stirring 6.93 g of deionized water, 0.274 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.246 g of sodium hydroxide, 5.80 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 4.58 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 8.17 g of silica sol (containing 40.0 wt% SiO₂) at room temperature for 4 hours. The final material ratio (molar ratio) was:

[0132] SiO2 / Al2O3 = 50;

[0133] NaOH / SiO2 = 0.16;

[0134] Methyltriethylammonium hydroxide / SiO2 = 0.20;

[0135] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.10;

[0136] H2O / SiO2 = 20.

[0137] The mixture was placed in a stainless steel reactor and heated at 150°C and 10 rpm for 5 days to crystallize. After crystallization, the mixture was filtered, washed, dried overnight in an oven at 100°C, and then calcined in air at 550°C for 6 hours. The XRD pattern of the obtained product was similar to... Figure 1 Similarly, the SSZ-13 molecular sieve has a CHA structure, with a yield of 89 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 52.1 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is similar to... Figure 2 Similarly, the crystals exhibit a nanoparticle-like morphology, aggregating into ellipsoidal clusters. The nanoparticles have a size of 35 nm, and the ellipsoidal clusters have a size of 1.2 μm. The sample has a specific surface area of ​​755 m². 2 / gram, with an external specific surface area of ​​78 m² measured by the BET method. 2 / g; Total pore volume 0.73cm 3 / gram, micropore volume is 0.26 cm³ 3 / gram.

[0138] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 823 μmol / g and the strong acid content was 387 μmol / g by NH3-TPD.

[0139] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of the 20-40 mesh particle size fraction, which was then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity 1.0 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 6 Similarly, the selectivity for propane in the products during the initial stage of the reaction is higher than 60%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 82%.

[0140] Example 8

[0141] 17.13 g of deionized water, 0.185 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.223 g of sodium hydroxide, 3.24 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 4.09 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 6.08 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0142] SiO2 / Al2O3 = 55;

[0143] NaOH / SiO2 = 0.18;

[0144] Methyltriethylammonium hydroxide / SiO2 = 0.15;

[0145] N,N,N-trimethyladamantane ammonium / SiO2 = 0.12;

[0146] H2O / SiO2 = 36.

[0147] The mixture was placed in a stainless steel reactor and heated at 155°C and 30 rpm for 4.5 days to crystallize. After crystallization, it was filtered, washed, dried overnight in a 100°C oven, and then calcined in air at 550°C for 6 hours. The XRD pattern of the product obtained was similar to... Figure 1 Similarly, the SSZ-13 molecular sieve, with a CHA structure, was obtained in a yield of 91 wt%. The SiO2 / Al2O3 molar ratio of the molecular sieve was determined to be 56.4 using inductively coupled plasma atomic emission spectrometry (ICP). The SEM image of the sample is similar to... Figure 2 Similarly, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters, with nanoparticles measuring 50 nm and spherical clusters measuring 1.6 μm. The sample has a specific surface area of ​​725 m². 2 / gram, with an external specific surface area of ​​64 m² measured by the BET method. 2 / g; Total pore volume 0.67cm 3 / gram, micropore volume is 0.23 cm³ 3 / gram.

[0148] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 763 μmol / g and the strong acid content was 371 μmol / g by NH3-TPD.

[0149] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particles, which were then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity (WHSV) 1.2 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 6 Similarly, the selectivity for propane in the products during the initial stage of the reaction is above 70%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 81%.

[0150] Example 9

[0151] 20.16 g of deionized water, 0.235 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.316 g of sodium hydroxide, 2.99 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 3.77 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 8.41 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0152] SiO2 / Al2O3 = 60;

[0153] NaOH / SiO2 = 0.18;

[0154] Methyltriethylammonium hydroxide / SiO2 = 0.10;

[0155] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.08;

[0156] H2O / SiO2 = 30.

[0157] The mixture was placed in a stainless steel reactor and heated to 170°C at 40 rpm for 2 days for crystallization. After crystallization, the mixture was filtered, washed, dried overnight in an oven at 100°C, and then calcined in air at 550°C for 6 hours. The XRD pattern of the obtained product was similar to... Figure 1 Similarly, the SSZ-13 molecular sieve has a CHA structure, with a yield of 90 wt%. Inductively coupled plasma atomic emission spectrometry (ICP) determined the SiO2 / Al2O3 molar ratio of the molecular sieve to be 61.5. SEM images of the samples are shown below. Figure 2 Similarly, the crystals exhibit a nanoparticle-like morphology, aggregating into ellipsoidal clusters. The nanoparticles have a size of 45 nm, and the ellipsoidal clusters have a size of 1.2 μm. The sample has a specific surface area of ​​699 m². 2 / gram, with an external specific surface area of ​​76 m² measured by the BET method. 2 / g; Total pore volume 0.71cm 3 / gram, micropore volume is 0.24 cm³ 3 / gram.

[0158] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 758 μmol / g and the strong acid content was 352 μmol / g by NH3-TPD.

[0159] The calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particles, which were then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 400℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity (WHSV) 1.8 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 3 Similarly, the selectivity for propane in the products during the initial stage of the reaction is higher than 60%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 82%.

[0160] Example 10

[0161] 17.28 g of deionized water, 0.335 g of sodium aluminate (containing 40.5 wt% Al₂O₃ and 30.6 wt% Na₂O), 0.567 g of sodium hydroxide, 5.53 g of methyltriethylammonium hydroxide solution (containing 25.00 wt% methyltriethylammonium hydroxide) (organic structure directing agent a), 10.91 g of N,N,N-trimethyladamantane ammonium solution (containing 25.12 wt% N,N,N-trimethyladamantane ammonium) (organic structure directing agent b), and 12.98 g of silica sol (containing 40.0 wt% SiO₂) were stirred at room temperature for 4 hours to obtain a mixture. The final material ratio (molar ratio) was:

[0162] SiO2 / Al2O3 = 65;

[0163] NaOH / SiO2 = 0.20;

[0164] Methyltriethylammonium hydroxide / SiO2 = 0.12;

[0165] N,N,N-trimethyladamantane ammonium / SiO2 = 0.15;

[0166] H2O / SiO2 = 24.

[0167] The mixture was placed in a stainless steel reactor and heated to 160°C at 20 rpm for 3 days for crystallization. After crystallization, the mixture was filtered, washed, dried overnight in a 100°C oven, and then calcined in air at 550°C for 6 hours. The XRD pattern of the obtained product was similar to... Figure 1 Similarly, the SSZ-13 molecular sieve, with a CHA structure, was obtained in a yield of 89 wt%. Inductively coupled plasma atomic emission spectrometry (ICP) determined the SiO2 / Al2O3 molar ratio of the molecular sieve to be 66.8. The SEM image of the sample is shown below. Figure 2 Similarly, the crystals exhibit a morphology of nanoparticles aggregated into spherical clusters, with nanoparticles measuring 50 nm and spherical clusters measuring 1.5 μm. The sample has a specific surface area of ​​706 m². 2 / gram, with an external specific surface area of ​​80 m² measured by the BET method. 2 / g; Total pore volume 0.70cm 3 / gram, micropore volume is 0.24 cm³ 3 / gram.

[0168] Sodium-type SSZ-13 molecular sieve was subjected to ammonium ion exchange with 0.2 mol / L NH4NO3 solution (mass ratio 1:20) at 45℃ for 2 hours, followed by centrifugation and washing. The ammonium ion exchange was repeated twice. The resulting sample was dried overnight at 100℃ and calcined in air at 550℃ for 6 hours to obtain hydrogen-type SSZ-13 molecular sieve sample. The total acid content of the molecular sieve was determined to be 726 μmol / g and the strong acid content was 338 μmol / g by NH3-TPD.

[0169] The above-mentioned calcined H-type SSZ-13 molecular sieve powder sample was crushed and sieved to obtain 1.0 g of 20-40 mesh particle size fraction, which was then placed in a fixed-bed reactor for methanol conversion reaction. The reaction conditions were: reaction temperature 420℃, reaction pressure atmospheric pressure, and methanol weight hourly space velocity 3 h⁻¹. -1 The products were analyzed using a Shimadzu GC-2014 gas chromatograph. Catalyst activity and product selectivity were compared with... Figure 3 Similarly, the selectivity for propane in the products during the initial stage of the reaction is higher than 50%; the diene selectivity for ethylene and propylene in the products within 30 minutes before the catalyst begins to deactivate is 83%.

[0170] Comparative Example 1

[0171] The material ratio is the same as in Example 1, except that N,N,N-trimethyladamantane ammonium (SDA1) is not added. The final material ratio (molar ratio) is:

[0172] SiO2 / Al2O3 = 30;

[0173] NaOH / SiO2 = 0.12;

[0174] Methyltriethylammonium hydroxide / SiO2 = 0.10;

[0175] N,N,N-Trimethyladamantaneammonium / SiO2=0;

[0176] H2O / SiO2 = 18.

[0177] The mixture was placed in a stainless steel reactor and heated at 160°C and 20 rpm for 3 days to crystallize. After crystallization, the mixture was filtered, washed, and dried overnight in an oven at 100°C. The XRD pattern of the obtained product is shown below. Figure 13 As shown, the sample is uncrystallized, has an amorphous structure, and is not a CHA structure molecular sieve.

[0178] Comparative Example 2

[0179] The material ratio is the same as in Example 1, except that the silicon-aluminum ratio is higher. The final material ratio (molar ratio) is:

[0180] SiO2 / Al2O3 = 100;

[0181] NaOH / SiO2 = 0.12;

[0182] Methyltriethylammonium hydroxide / SiO2 = 0.10;

[0183] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.05;

[0184] H2O / SiO2 = 18.

[0185] The mixture was placed in a stainless steel reactor and heated at 160°C and 20 rpm for 3 days to crystallize. After crystallization, the mixture was filtered, washed, and dried overnight in an oven at 100°C. The XRD pattern of the obtained product is shown below. Figure 14 As shown, the sample is a symbiotic structure of amorphous MTW and CHA, and is not a pure phase CHA structure molecular sieve.

[0186] Comparative Example 3

[0187] The material ratio is the same as in Example 1, except that the alkalinity is lower. The final material ratio (molar ratio) is:

[0188] SiO2 / Al2O3 = 30;

[0189] NaOH / SiO2 = 0.08;

[0190] Methyltriethylammonium hydroxide / SiO2 = 0.10;

[0191] N,N,N-Trimethyladamantaneammonium / SiO2 = 0.05;

[0192] H2O / SiO2 = 18.

[0193] The mixture was placed in a stainless steel reactor and heated at 160°C and 20 rpm for 3 days to crystallize. After crystallization, the mixture was filtered, washed, and dried overnight in an oven at 100°C. The XRD pattern of the obtained product is shown below. Figure 15 As shown, the sample is uncrystallized, has an amorphous structure, and is not a CHA structure molecular sieve.

[0194] Comparative Example 4

[0195] The material ratio is the same as in Example 1, except that the added sodium aluminate contains different contents of Al2O3 and Na2O (containing 50.6% by weight of Al2O3 and 45.2% by weight of Na2O). The raw materials are prepared in the same amount of substances.

[0196] The mixture was placed in a stainless steel reactor and heated to crystallize at 160°C with a stirring speed of 20 rpm for 3 days. After crystallization, the mixture was filtered, washed, and dried overnight in an oven at 100°C. The SEM image of the obtained product is shown below. Figure 16 As shown, the sample has a cubic morphology, not a spherical morphology composed of nanocrystals.

[0197] The specific embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A spherical SSZ-13 molecular sieve, comprising spherical or ellipsoidal particles formed by the aggregation of nanocrystals, with a particle size of 0.2~5.0 μm, wherein the SiO2 / Al2O3 molar ratio of the spherical SSZ-13 molecular sieve is 29.0~80.0; and the total specific surface area of ​​the spherical nano-SSZ-13 molecular sieve is not less than 500 m². 2 / gram, external specific surface area not less than 50 m² 2 / g; the total pore volume of the spherical nano SSZ-13 molecular sieve is not less than 0.30 cm³. 3 / gram, micropore volume not less than 0.20 cm³ 3 / g; After the spherical SSZ-13 molecular sieve is subjected to ammonium ion exchange treatment to form hydrogen: the total acid content of the molecular sieve is not less than 600μmol / g, and the strong acid content of the molecular sieve is not less than 300μmol / g.

2. The spherical SSZ-13 molecular sieve according to claim 1, characterized in that, The SiO2 / Al2O3 molar ratio of the spherical SSZ-13 molecular sieve is 30.0~70.

0.

3. The spherical SSZ-13 molecular sieve according to claim 1, characterized in that, The spherical SSZ-13 molecular sieve has a particle size of 0.25~4.50μm.

4. The spherical SSZ-13 molecular sieve according to claim 1, characterized in that, The total specific surface area of ​​the spherical nano-SSZ-13 molecular sieve is 500~850 m². 2 / gram; external specific surface area is 50~120 m² 2 / g; and / or, the total pore volume of the spherical nano SSZ-13 molecular sieve is 0.30~0.75 cm³. 3 / g; micropore volume is 0.20~0.30 cm³. 3 / gram.

5. The spherical SSZ-13 molecular sieve according to claim 1, characterized in that, The spherical SSZ-13 molecular sieve, after undergoing ammonium ion exchange treatment to become the hydrogen form: The total acidity of the molecular sieve is 600~1500 μmol / g; and / or, The molecular sieve has a strong acid content of 300~800 μmol / g.

6. A method for preparing the spherical SSZ-13 molecular sieve according to any one of claims 1-5, comprising the following steps: A silicon source, an aluminum source, sodium hydroxide, organic structure directing agent a, organic structure directing agent b, and water are mixed and crystallized to obtain the spherical SSZ-13 molecular sieve; and optionally, the spherical SSZ-13 molecular sieve is obtained by calcination; wherein the aluminum source is sodium aluminate, and the content of Al2O3 in the sodium aluminate is 38%~43% by weight, and the content of Na2O is 30%~33% by weight; wherein organic structure directing agent a is methyltriethylammonium hydroxide; and wherein organic structure directing agent b is N,N,N-trimethyladamantane ammonium.

7. The preparation method according to claim 6, characterized in that, The added silicon source is SiO2, the aluminum source is Al2O3, sodium hydroxide, organic structure directing agent a, organic structure directing agent b, and water, in a molar ratio of SiO2:Al2O3:NaOH:SDA1:SDA2:H2O=1:0.013~0.034:0.10~0.22:0.05~0.20:0.05~0.15:12~50.

8. The preparation method according to claim 7, characterized in that, The molar ratio is SiO2:Al2O3:NaOH:SDA1:SDA2:H2O=1:0.015~0.033:0.12~0.20:0.10~0.20:0.05~0.15:15~40.

9. The preparation method according to claim 6, characterized in that, The silicon source is silica sol.

10. The preparation method according to claim 6, characterized in that, The crystallization conditions of the reaction mixture are 130~180℃ for 1.75~6.0 days.

11. The preparation method according to claim 10, characterized in that, The crystallization conditions of the reaction mixture are 140~170℃ for 2.0~5.0 days.

12. The preparation method according to claim 6, characterized in that, The crystallization process of the reaction mixture is a dynamic crystallization by rotation or stirring, with a rotation or stirring speed of 10~300 rpm.

13. The preparation method according to claim 12, characterized in that, The rotation or stirring speed is 20~150 rpm.

14. A spherical SSZ-13 molecular sieve composition comprising a spherical SSZ-13 molecular sieve according to any one of claims 1 to 5 or a spherical SSZ-13 molecular sieve prepared according to any one of claims 6 to 13, and a binder.

15. The use of the spherical SSZ-13 molecular sieve according to any one of claims 1 to 5, or the spherical SSZ-13 molecular sieve prepared according to any one of claims 6 to 13, or the spherical SSZ-13 molecular sieve composition according to claim 14 as a catalyst in organic matter conversion.

16. The application according to claim 15, characterized in that, The spherical SSZ-13 molecular sieve is used as a catalyst in the methanol conversion reaction. The reaction process conditions are: reaction temperature 350~500℃, mass hourly space velocity (HHSV) 0.5~8h. -1 .

17. The application according to claim 16, characterized in that, Mass hourly space velocity (MHSV) is 0.75–6 h. -1 .

Images