SCM-40 molecular sieve and its preparation method

Abstract

The present invention discloses SCM-40 molecular sieve and its preparation method. The chemical composition of the SCM-40 molecular sieve, in terms of molar ratio, is Al2O3:P2O5 = (0.5-1.1):1. The XRD pattern of the SCM-40 molecular sieve contains X-ray diffraction peaks at 2θ of 9.50±0.1, 10.07±0.1, 12.67±0.1, 19.66±0.1, 20.43±0.1, 24.23±0.1, 29.18±0.1, and 30.69±0.1, where the peak at 2θ of 9.50±0.1 is the strongest peak. The SCM-40 molecular sieve provided by the present invention has special XRD diffraction peaks and can be applied in adsorbents or catalysts.

Description

Technical Field

[0001] The invention belongs to the field of molecular sieves, and specifically relates to a new type of molecular sieve, namely, SCM-40 molecular sieve and a preparation method thereof. Background Art

[0002] Molecular sieves are a type of porous crystalline material that is widely used in chemical fields such as oil refining and catalysis. Different pore structures reflect different macroscopic properties such as adsorption and catalysis, and molecular sieves with different structures have also been synthesized. At present, more than 250 types of molecular sieves with known structures have been discovered (including partially disordered ones). Since molecular sieves have uniform and regular pores, and the pore size is of the same order of magnitude as that of small organic molecules, in chemical reactions, the molecules entering the molecular sieve can be "screened" according to the spatial size of the molecules, thereby obtaining a certain selective adsorption and catalytic shape-selective effect. The framework of the molecular sieve is usually composed of coordinated tetrahedrons (TO4) connected by common vertices (usually oxygen atoms). For conventional zeolite molecular sieves, the tetrahedrons in the framework are mainly silicon-oxygen tetrahedrons and aluminum-oxygen tetrahedrons. These two tetrahedrons can also be replaced by other tetrahedrons, thereby forming many molecular sieves with various framework structures or various framework compositions.

[0003] In 1971, Flanigen et al. (Molecular Sieve Zeolites-I, ACS, Washington DC) reported the synthesis of aluminum phosphate molecular sieves, which can be understood as the silicon oxygen tetrahedron in the zeolite molecular sieve is replaced by phosphorus oxygen tetrahedron to form a molecular sieve. The framework of this type of molecular sieve is composed of AlO4 - and PO4 +It is composed of oxygen atoms connected together, and the entire molecular sieve framework shows electrical neutrality. Similar to zeolite molecular sieves, the aluminum-oxygen tetrahedra or phosphorus-oxygen tetrahedra in aluminophosphate molecular sieves can also be replaced by other tetrahedra. The most common ones are silicon-oxygen tetrahedra and zinc-oxygen tetrahedra. Due to the introduction of these tetrahedra, new properties are imparted to aluminophosphate molecular sieves. Compared with zeolite molecular sieves, the research on the artificial synthesis of aluminophosphate molecular sieves started relatively late. Under hydrothermal synthesis conditions, the oxides of aluminum, silicon, and phosphorus were mixed to obtain silicoaluminophosphate molecular sieves with the same crystal structures as analcime, chabazite, phillipsite-harmotome, L-type molecular sieve, A-type molecular sieve, B-type molecular sieve, etc., where the phosphorus content was 5% - 25% (calculated as P2O5), but no molecular sieves with structures different from known zeolite molecular sieves were found. The US Patent US 4310440 in 1982 used organic amines or quaternary ammonium compounds as template agents to hydrothermally synthesize a series of aluminophosphate molecular sieves, including: AlPO4-5, AlPO4-8, AlPO4-9, AlPO4-11, AlPO4-12, AlPO4-14, AlPO4-16, AlPO4-17, AlPO4-18, AlPO4-20, AlPO4-21, AlPO4-22, AlPO4-23, AlPO4-25, AlPO4-26, AlPO4-28, AlPO4-31, etc. With the continuous deepening of the understanding of factors such as the structure, performance, synthesis method, and conditions of molecular sieves and the continuous progress of synthesis technology, new-structured molecular sieves are constantly being synthesized. For the synthesis of aluminophosphate molecular sieves, the type of organic template agent is one of the key factors determining its structure. So far, organic amines are still the most widely used template agents in the synthesis of aluminophosphate molecular sieves. Compared with silica-alumina zeolite molecular sieves, the industrial applications of aluminophosphate molecular sieves are still rare. At present, only a few molecular sieves have obtained practical industrial applications, such as SAPO-34 and SAPO-11 molecular sieves. Jiao et al. (Feng Jiao, Jinjing Li, Xiulian Pan, et al. Science, 2016, 351, 1065 - 1068) reported that SAPO molecular sieves, as part of the coupling catalyst in the reaction of syngas to olefins, achieved good catalytic effects.Su et al. (Su, J., Zhou, H., Liu, S. et al. Syngas to light olefins conversion with high olefin / paraffin ratio using ZnCrOx / AlPO-18 bifunctional catalysts. Nat Commun 10, 1297 (2019).) revealed that bifunctional catalysts prepared from aluminophosphate molecular sieves and metal oxides have excellent performance in the direct conversion of syngas to olefins with a high olefin / paraffin ratio. It can be seen from the above that aluminophosphate molecular sieves have great potential for industrial applications.

[0004] Since different pore structures and elemental compositions determine the unique physical and chemical and catalytic properties of molecular sieves, the development of molecular sieves with special structures, including those with special structures, is particularly important. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a novel molecular sieve not involved in the prior art, namely SCM-40 molecular sieve and its preparation method.

[0006] In the first aspect of the present invention, an SCM-40 molecular sieve is provided, wherein the chemical composition of the SCM-40 molecular sieve, in terms of molar ratio, is Al2O3∶P2O5 = (0.5 - 1.1)∶1, and the XRD pattern of the SCM-40 molecular sieve includes X-ray diffraction peaks at 2θ of 9.50 ± 0.1, 10.07 ± 0.1, 12.67 ± 0.1, 19.66 ± 0.1, 20.43 ± 0.1, 24.23 ± 0.1, 29.18 ± 0.1, 30.69 ± 0.1, and the peak at 2θ of 9.50 ± 0.1 is the strongest peak.

[0007] Further, the XRD pattern of the SCM-40 molecular sieve includes the X-ray diffraction peaks shown in the following table:

[0008] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 9.50±0.1 100 10.07±0.1 20-80 12.67±0.1 20-80 19.66±0.1 20-80 20.43±0.1 20-80 24.23±0.1 20-80 29.18±0.1 20-80 30.69±0.1 20-80

[0009] Further, the XRD pattern of the SCM-40 molecular sieve further includes the X-ray diffraction peaks shown in the following table:

[0010]

[0011]

[0012] Further, the XRD pattern of the SCM-40 molecular sieve further includes the X-ray diffraction peaks shown in the following table:

[0013] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 20.16±0.1 5-30 21.29±0.1 5-30 22.47±0.1 5-30 22.77±0.1 5-30 32.79±0.1 5-30

[0014] The second aspect of the present invention provides a method for preparing the above-mentioned SCM-40 molecular sieve, including:

[0015] a) Mixing a phosphoaluminate precursor, an organic base R1, an organic compound R2, a fluorine source, water, and optionally an aluminum source A or a phosphorus source A to obtain a synthesis mother liquor;

[0016] b) Crystallizing, drying, and calcining the synthesis mother liquor obtained in step a) to obtain the SCM-40 molecular sieve;

[0017] The phosphoaluminate precursor has a chemical composition as shown in the formula "Al2O3∶xP2O5", where 0.8 ≤ x ≤ 2; the XRD pattern of the phosphoaluminate precursor mainly includes the X-ray diffraction peaks shown in the following table:

[0018] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 7.59±0.2 100 10.81±0.1 5-50 16.52±0.1 5-50 17.97±0.1 5-50 23.34±0.05 5-50 34.74±0.05 5-50

[0019] Further, the XRD pattern of the phosphoaluminate precursor further includes the X-ray diffraction peaks shown in the following table:

[0020]

[0021]

[0022] Further, the XRD pattern of the phosphoaluminate precursor further includes the X-ray diffraction peaks shown in the following table:

[0023] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 12.09±0.1 5-50 19.77±0.1 5-50 31.33±0.01 5-50 38.29±0.01 5-50

[0024] Further, in the synthesis mother liquor, the molar ratios of each material are as follows: the aluminum source A is calculated as Al2O3, the phosphorus source A is calculated as P2O5, the phosphoaluminate precursor is calculated as Al2O3 and P2O5, the organic base R1, the organic compound R2, the fluorine source is calculated as HF, and water is calculated as H2O, (0.5 - 0.88)Al2O3∶1P2O5∶(0.3 - 0.8)R1∶(1 - 2)R2∶(0.5 - 1.8)HF∶(50 - 130)H2O, preferably, (0.5 - 0.85)Al2O3∶1P2O5∶(0.3 - 0.8)R1∶(1 - 2)R2∶(0.5 - 1.8)HF∶(50 - 130)H2O. Among them, the dosage of the optional aluminum source A or phosphorus source A is determined according to the amounts of Al2O3 and P2O5 in the phosphoaluminate precursor, that is, when the amounts of Al2O3 and P2O5 provided by the phosphoaluminate precursor meet the above ratio requirements, the aluminum source A and the phosphorus source A are not added, and when the amount of Al2O3 or P2O5 provided by the phosphoaluminate precursor cannot meet the above ratio requirements, the aluminum source A or the phosphorus source A is added to meet the above ratio requirements.

[0025] Further, the phosphorus source A is selected from at least one of phosphoric acid, ammonium monohydrogen phosphate, ammonium dihydrogen phosphate, etc.

[0026] Further, the aluminum source A is selected from one or more of pseudo-boehmite, aluminum isopropoxide, aluminum sol, alumina, etc.

[0027] Further, the organic base R1 is one or more of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, etc.

[0028] Further, the organic matter R2 is 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and its chemical structural formula is shown as follows:

[0029]

[0030] Further, the fluorine source is selected from HF aqueous solution.

[0031] Further, in step a), there is no particular limitation on the addition order of each material. Preferably, water, aluminum source A and the aluminophosphate precursor are first mixed evenly, then the organic matter R2 and the organic base R1 are added in sequence and mixed evenly, and then the fluorine source is added.

[0032] Further, in step b), the crystallization conditions are as follows: the crystallization temperature is 120°C - 200°C, and the crystallization time is 8 - 100 hours; preferably, the crystallization temperature is 130°C - 190°C, and the crystallization time is 12 - 80 hours; or the segmented crystallization method is adopted. The crystallization temperature in the first stage is 130°C - 190°C, and the crystallization time is 48 - 72 hours. Preferably, the crystallization temperature is 130°C - 160°C, and the crystallization time is 24 - 72 hours; the crystallization temperature in the second stage is 160°C - 200°C, and the crystallization time is 4 - 24 hours. Preferably, the crystallization temperature is 170°C - 200°C, and the crystallization time is 5 - 18 hours. Among them, the crystallization temperature in the second stage is at least 10°C higher than that in the first stage, preferably at least 20°C higher.

[0033] Further, after the crystallization step in step b), the SCM-40 molecular sieve product can be separated from the obtained mixture by any conventionally known separation method, such as separation and washing. Here, the separation and washing can be carried out in any manner conventionally known in the art, and the separation such as centrifugation or filtration, suction filtration.

[0034] Further, the drying conditions in step b) are as follows: the drying temperature is 40 - 120°C, preferably 50 - 80°C, and the drying time is 8 - 48 hours, preferably 12 - 36 hours. This drying can be carried out under normal pressure or under reduced pressure. For energy conservation, it is usually carried out under normal pressure.

[0035] Further, the calcination conditions in step b) are as follows: the calcination temperature is 450°C - 650°C, the calcination time is 1 - 8 hours. Preferably, the calcination temperature is 480°C - 550°C, the calcination time is 3 - 6 hours, and the atmosphere is an oxygen-containing gas (such as air).

[0036] In the third aspect of the present invention, a molecular sieve composition is provided, including the SCM-40 molecular sieve according to any of the foregoing aspects or the SCM-40 molecular sieve prepared by the preparation method according to any of the foregoing aspects, and a binder.

[0037] In the fourth aspect of the present invention, an application of a molecular sieve is provided, which is the application of the SCM-40 molecular sieve according to any of the foregoing aspects, or the SCM-40 molecular sieve prepared by the preparation method according to any of the foregoing aspects, or the molecular sieve composition according to any of the foregoing aspects in an adsorbent or a catalyst.

[0038] Further, the SCM-40 molecular sieve or the SCM-40 molecular sieve composition is used as an adsorbent, for example, to separate at least one component from a mixture of multiple components in the gas phase or liquid phase. Accordingly, the at least one component can be partially or substantially completely separated from the mixture of various components. The specific method is, for example, to bring the mixture into contact with the SCM-40 molecular sieve or the SCM-40 molecular sieve composition, and selectively adsorb this component.

[0039] Further, the SCM-40 molecular sieve or the SCM-40 molecular sieve composition can be used in a catalyst for organic matter conversion.

[0040] The SCM-40 molecular sieve of the present invention is a novel molecular sieve with special XRD diffraction peaks, enriching the types of molecular sieves. Description of the Drawings

[0041] Figure 1 XRD pattern of the aluminophosphate precursor A obtained in Example 1;

[0042] Figure 2 XRD pattern of the aluminophosphate precursor B obtained in Example 2;

[0043] Figure 3 XRD pattern of the SCM-40 molecular sieve obtained in Example 3;

[0044] Figure 4 XRD pattern of the SCM-40 molecular sieve obtained in Example 11;

[0045] Figure 5 XRD pattern of the product obtained in Comparative Example 1;

[0046] Figure 6XRD pattern of the product obtained in Comparative Example 2. Detailed Embodiments

[0047] The following provides a detailed description of the specific embodiments of the present invention. The protection scope of the present invention is not limited by these specific embodiments.

[0048] In the present invention, the structure of the molecular sieve is determined by X-ray diffraction pattern (XRD). The X-ray diffraction pattern (XRD) of the molecular sieve is measured by an X'Pert PRO type X-ray powder diffractometer (XRD) produced by PANalytical B.V. in the Netherlands, using a Cu-Kα ray source. Nickel filter, working voltage 40 kV, current 40 mA, scanning range 3 - 50°.

[0049] In the present invention, the compositions of SiO2, Al2O3 and P2O5 in the molecular sieve are measured by ICP method. An inductively coupled plasma emission spectrometer of Varian Analytical 725-ES type produced by Varian Inc. in the United States is used to analyze the element ratios in the sample.

[0050] The aluminophosphate precursor of the present invention has a schematic chemical composition as shown in the formula "Al2O3∶xP2O5", where 0.8 ≤ x ≤ 2. The XRD pattern of the aluminophosphate precursor includes the following X-ray diffraction peaks shown in the table:

[0051] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 7.59±0.2 100 10.81±0.1 5-50 16.52±0.1 5-50 17.97±0.1 5-50 23.34±0.05 5-50 34.74±0.05 5-50

[0052] Further, the XRD pattern of the aluminophosphate precursor also includes the following X-ray diffraction peaks shown in the table:

[0053]

[0054]

[0055] Further, the XRD pattern of the aluminophosphate precursor also includes the following X-ray diffraction peaks shown in the table:

[0056] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 12.09±0.1 5-50 19.77±0.1 5-50 31.33±0.01 5-50 38.29±0.01 5-50

[0057] Further, the preparation method of the aluminophosphate precursor of the present invention includes: subjecting a mixture containing aluminum source B, phosphorus source B, organic template R A and organic template R B , solvent S1, solvent S2 and solvent S3 to crystallization treatment to obtain the aluminophosphate precursor;

[0058] wherein, the organic template R A is selected from one or more of quaternary ammonium salts or quaternary ammonium bases; R BOne or more selected from imidazole or pyrrolidine derivatives; the solvent S1 is selected from one or more of amide solvents; the solvent S2 is selected from one or more of cyclic organic solvents; S3 is selected from one or more of water or lower alcohols.

[0059] Furthermore, in the preparation method of the aluminophosphate precursor, the organic template R A is selected from one or more of tetraethylammonium bromide, tetraethylammonium hydroxide, tetrapropylammonium bromide, tetrapropylammonium hydroxide, tetrabutylammonium bromide, and tetrabutylammonium hydroxide; the organic template R B is selected from one or more of imidazole, 2-methylimidazole, 4-methylimidazole, 1-(3-aminopropyl)imidazole, 2-ethyl-4-methylimidazole, pyrrolidine, 1-(3-pyrrolidino)pyrrolidine, and N-ethyl-2-aminomethylpyrrolidine; the solvent S1 is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, and N,N-dibutylformamide; the solvent S2 is selected from one or more of 1,4-dioxane, cyclohexane, cyclohexanone, and ; the solvent S3 is selected from one or more of methanol, ethanol, ethylene glycol, butanol, cyclohexanol, and water.

[0060] Furthermore, in the preparation method of the aluminophosphate precursor, the organic template R A is preferably one or more of tetraethylammonium bromide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide; the organic template R B is preferably one or more of 1-(3-aminopropyl)imidazole, 2-ethyl-4-methylimidazole, and N-ethyl-2-aminomethylpyrrolidine; the solvent S1 is preferably one or more of N,N-dimethylacetamide and N,N-dibutylformamide; the solvent S2 is preferably one or two of 1,4-dioxane and cyclohexanone; the solvent S3 is preferably one or two of ethanol and water, and more preferably deionized water.

[0061] Furthermore, in the preparation method of the aluminophosphate precursor, in the mixture, the aluminum source B is calculated as Al2O3, the phosphorus source B is calculated as P2O5, the organic template R A +R B 、the solvents S1+S2+S3 have the following molar composition: P2O5 / Al2O3 = 0.75 - 2.2, preferably 1 - 2; the template R A +R B / Al2O3 = 1 - 80, preferably 5 - 50; the solvents S1+S2+S3 / Al2O3 = 5 - 500, preferably 35 - 120.

[0062] Furthermore, in the preparation method of the aluminophosphate precursor, the organic template RA The molar ratio with the organic template R B is 0.01 - 1:1, preferably 0.1 - 0.25:1.

[0063] Furthermore, in the preparation method of the aluminophosphate precursor, the molar ratio of the solvent S1, solvent S2, and solvent S3 is 1:0.01 - 1:1 - 100, preferably 1:0.05 - 0.5:10 - 80.

[0064] Furthermore, in the preparation method of the aluminophosphate precursor, the aluminum source B is selected from one or more of aluminum isopropoxide, aluminate, meta - aluminate, aluminum salt, aluminum hydroxide, aluminum oxide, and aluminum - containing minerals, preferably one or two of aluminate and meta - aluminate; the phosphorus source B is selected from at least one of phosphoric acid, ammonium monohydrogen phosphate, and ammonium dihydrogen phosphate, preferably orthophosphoric acid.

[0065] Furthermore, in the preparation method of the aluminophosphate precursor, before the crystallization treatment, stirring and aging treatments are first carried out. The stirring time is 0.5 - 5 h, and the aging treatment time is 1 - 12 h.

[0066] Furthermore, in the preparation method of the aluminophosphate precursor, the conditions of the crystallization treatment include: the crystallization temperature is 120 - 200 °C, preferably 140 - 180 °C, more preferably 140 - 160 °C; the crystallization time is 1 - 5 d, preferably 3 - 5 d, more preferably 4 - 5 d.

[0067] Furthermore, in the preparation method of the aluminophosphate precursor, after the crystallization treatment, conventional post - treatments are carried out, such as the steps of filtering, washing, and drying to obtain the molecular sieve. The filtering, washing, and drying can be carried out in any manner conventionally known in the art, where the separation is by centrifugation or filtration, suction filtration. The drying temperature can be 40 - 120 °C, preferably 50 - 80 °C; as the drying time, it is 8 - 48 hours, preferably 12 - 24 hours. This drying can be carried out at normal pressure or under reduced pressure. For energy conservation, it is often carried out at normal pressure.

[0068] The technical solutions of the present invention will be described in detail below with reference to the examples.

[0069]

Example 1

[0070] Dissolve 38 g of aluminum nitrate [Al(NO3)3·9H2O] in 43 mL of deionized water. With stirring, add 25.2 g of phosphoric acid (purity ≥ 85 wt%), 151 g of tetrabutylammonium hydroxide (40 wt% aqueous solution), and 145.6 g of 1-(3-aminopropyl)imidazole. After stirring for 0.5 h and aging for 12 h, solution A is obtained. Then, add 16 mL of N,N-dibutylformamide and 4.6 mL of cyclohexanone to solution A. After stirring for 3.5 h, heat-treat at 90 °C for 8 h to form a homogeneous crystallization mixture B, where the molar ratio of the aluminum source calculated as Al2O3, the phosphorus source calculated as P2O5, the total template agent, and the total solvent is: Al2O3∶P2O5∶template agent R∶solvent S = 1∶2.1∶7∶40, and the template agent R A (tetrabutylammonium hydroxide)∶template agent R B (1-(3-aminopropyl)imidazole) = 0.2 (molar ratio), and the molar ratio of solvent S1 (N,N-dibutylformamide)∶solvent S2 (cyclohexanone)∶solvent S3 (water) = 1∶0.5∶78.5; Place the above crystallization mixture B in a crystallization kettle with a polytetrafluoroethylene liner, crystallize at 140 °C for 5 d, filter and wash the product, and then dry at 80 °C for 24 h to obtain the aluminophosphate precursor, denoted as A, for standby. Among them, in the aluminophosphate precursor A, Al2O3∶P2O5 = 1∶2. The XRD pattern of the aluminophosphate precursor A is shown in Figure 1 , that is, it includes the X-ray diffraction peaks shown in Table 1:

[0071] Table 1

[0072] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 7.41 100 10.71 25 12.00 6 14.21 5 16.45 32 17.94 36 19.73 9 21.00 10 23.33 22 24.27 18 26.03 18 27.80 11 28.15 13 30.01 10 31.34 5 34.71 7 38.28 6

[0073]

Example 2

[0074] Dissolve 33.3 g of aluminum sulfate [Al2(SO4)3·18H2O] in 66.3 mL of water. With stirring, add 5.2 g of phosphoric acid (purity ≥ 85 wt%), 117.0 g of tetrabutylammonium hydroxide (40 wt% aqueous solution), and 102.6 g of 1-(3-aminopropyl)imidazole to obtain a mixed solution. After stirring for 3 h and aging for 6 h, solution A is obtained. Then, add 255 mL of N,N-dibutylformamide and 48 mL of cyclohexanone to the mixture A. After stirring for 4.5 h, heat-treat at 80 °C for 12 h to form a homogeneous mixture B, where the molar ratio of the aluminum source calculated as Al2O3, the phosphorus source calculated as P2O5, the template agent, and the solvent is: Al2O3∶P2O5∶total template agent R∶total solvent S = 1∶0.9∶10∶80, and the template agent R A (tetrabutylammonium hydroxide)∶template agent R B(1-(3-aminopropyl)imidazole) = 0.22 (molar ratio), solvent S1 (N,N-dibutylformamide)∶solvent S2 (cyclohexanone)∶solvent S3 (water) = 1∶0.3∶48 (molar ratio); The above mixture B was placed in a crystallization kettle with a Teflon liner and crystallized at 140 °C for 5 d. The product was filtered, washed, and dried at 80 °C for 24 h to obtain an aluminum phosphate precursor, denoted as B, for later use. Among them, in the aluminum phosphate precursor B, Al2O3∶P2O5 = 1∶0.92. The XRD pattern of the aluminum phosphate precursor B is shown in Figure 2 , that is, it includes the X-ray diffraction peaks shown in Table 2:

[0075] Table 2

[0076] 2θ (°) <![CDATA[Relative intensity, [(I / I0)×100]]]> 7.49 100 10.77 35 12.01 5 14.18 15 16.43 38 17.87 40 19.70 8 20.96 12 23.32 30 24.22 26 26.03 23 27.80 17 28.15 20 30.01 18 31.32 8 34.74 8 38.28 5

[0077]

Example 3

[0078] Weigh 24 g of water, add 2.17 g of aluminum isopropoxide and 6 g of the aluminum phosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, it was loaded into a high-pressure kettle with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and separate, wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 60 °C for 32 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1∶1. The XRD pattern of this SCM-40 molecular sieve is shown in Figure 3 , that is, it includes the main X-ray diffraction peaks shown in Table 3:

[0079] Table 3

[0080]

[0081]

[0082]

Example 4

[0083] Weigh 24 g of water, add 1.55 g of pseudo-boehmite and 6 g of aluminophosphate precursor A, and stir at room temperature for 1 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and separate, wash (the centrifugation and washing operations are repeated 2-3 times), dry at 80 °C for 16 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 4:

[0084] Table 4

[0085]

[0086]

[0087]

Example 5

[0088] Weigh 24 g of water, 0.93 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 3.3 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and separate, wash (the centrifugation and washing operations are repeated 2-3 times), dry at 80 °C for 18 h, and calcine in an air atmosphere at 500 °C for 8 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 0.9∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 5:

[0089] Table 5

[0090]

[0091]

[0092]

Example 6

[0093] Weigh 24 g of water, 0.62 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 3.3 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 0.5 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 70 °C for 24 h, and calcine in air atmosphere at 450 °C for 10 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 0.9∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 6:

[0094] Table 6

[0095]

[0096]

[0097]

Example 7

[0098] Weigh 24 g of water, add 0.31 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 3.3 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 0.43 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 50 °C for 36 h, and calcine in air atmosphere at 600 °C for 3 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 0.8∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 7:

[0099] Table 7

[0100]

[0101]

[0102]

Example 8

[0103] Weigh 24 g of water, 2.17 g of aluminum isopropoxide, and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 2.73 g of 25 wt% tetramethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and separate, wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 80 °C for 16 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 8:

[0104] Table 8

[0105]

[0106]

[0107]

Example 9

[0108] Weigh 24 g of water, 2.17 g of aluminum isopropoxide, and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 6.1 g of 25 wt% tetrapropylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and separate, wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 80 °C for 18 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 9:

[0109] Table 9

[0110]

[0111]

[0112]

Example 10

[0113] Weigh 24 g of water, add 2.17 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide aqueous solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 180 °C for 24 h; after cooling, separate and wash (repeat the centrifugal washing operation 2 - 3 times), dry at 70 °C for 24 h, and calcine in air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 10:

[0114] Table 10

[0115]

[0116]

[0117]

Example 11

[0118] Weigh 24 g of water, add 2 g of diammonium hydrogen phosphate, dissolve it and then add 2.73 g of aluminophosphate precursor B, and stir at room temperature for 3 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide aqueous solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; then raise the temperature to 180 °C and crystallize at this temperature for 8 h. After cooling, separate and wash (repeat the centrifugal washing operation 2 - 3 times), dry at 70 °C for 24 h, and calcine in air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 0.95∶1. The XRD pattern of this SCM-40 molecular sieve is shown in Figure 4 , that is, it includes the main X-ray diffraction peaks shown in Table 11:

[0119] Table 11

[0120]

[0121]

[0122]

Example 12

[0123] Weigh 28 g of water, add 2.17 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 7.8 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1.3 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 160 °C for 36 h; crystallize at 200 °C for 5 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 70 °C for 24 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 1.1∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 12:

[0124] Table 12

[0125]

[0126]

[0127]

Example 13

[0128] Weigh 28 g of water, add 2.17 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, and stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide, and then add 6.2 g of 25 wt% tetraethylammonium hydroxide solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 130 °C for 72 h; crystallize at 190 °C for 8 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2 - 3 times), dry at 70 °C for 24 h, and calcine in an air atmosphere at 550 °C for 6 h to obtain SCM-40 molecular sieve. Its chemical composition, in terms of molar ratio, is Al2O3∶P2O5 = 0.98∶1. The XRD pattern of this SCM-40 molecular sieve includes the main X-ray diffraction peaks shown in Table 13:

[0129] Table 13

[0130]

[0131]

[0132]

Comparative Example 1

[0133] Weigh 24 g of water, add 5.4 g of aluminum isopropoxide, stir at room temperature for 1 h, then add 3.51 g of phosphoric acid, and stir at room temperature for 3 h; add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide aqueous solution. After stirring at room temperature for 3 h, add 1 g of 40 wt% HF solution. After stirring evenly, transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2-3 times), dry at 60 °C for 32 h, and calcine in an air atmosphere at 550 °C for 6 h. The structure collapses into an amorphous form, rather than the SCM-40 molecular sieve. The specific XRD pattern is shown in Figure 5 .

[0134]

Comparative Example 2

[0135] Weigh 24 g of water, add 2.17 g of aluminum isopropoxide and 6 g of aluminophosphate precursor A, stir at room temperature for 2 h; then add 4.75 g of 6-N,N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, and then add 4.4 g of 25 wt% tetraethylammonium hydroxide solution. Stir at room temperature for 3 h, and then transfer it to a high-pressure autoclave with a Teflon liner. Crystallize at 140 °C for 66 h; crystallize at 180 °C for 8 h. After cooling, centrifuge and wash (the centrifugation and washing operations are repeated 2-3 times), dry at 60 °C for 32 h, and calcine in an air atmosphere at 550 °C for 6 h. The obtained product is not the SCM-40 molecular sieve. The specific XRD pattern is shown in Figure 6 .

Claims

1. A SCM-40 molecular sieve, characterized in that The chemical composition of the SCM-40 molecular sieve, in terms of molar ratio, is Al2O3:P2O5 = (0.5 - 1.1):

1. The XRD pattern of the SCM-40 molecular sieve contains X-ray diffraction peaks at 2θ = 9.50±0.1, 10.07±0.1, 12.67±0.1, 19.66±0.1, 20.43±0.1, 24.23±0.1, 29.18±0.1, 30.69±0.1, where the peak at 2θ = 9.50±0.1 is the strongest peak.

2. The SCM-40 molecular sieve according to claim 1, characterized in that, The XRD pattern of the SCM-40 molecular sieve contains the X-ray diffraction peaks shown in the following table: 。 3. The SCM-40 molecular sieve according to claim 1, characterized in that, The XRD pattern of the SCM-40 molecular sieve further contains the X-ray diffraction peaks shown in the following table: 。 4. The SCM-40 molecular sieve according to any one of claims 1-3, characterized in that, The XRD pattern of the SCM-40 molecular sieve further contains the X-ray diffraction peaks shown in the following table: 。 5. The preparation method of the SCM-40 molecular sieve according to any one of claims 1 - 4, comprising: a) Mixing a phosphoaluminate precursor, an organic base R1, an organic compound R2, a fluorine source, water, and optionally an aluminum source A or a phosphorus source A to obtain a synthesis mother liquor; wherein, the organic base R1 is one or more of tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrapropylammonium hydroxide; the organic compound R2 is 6-N,N-dimethylaminohexyl-2-hydroxyethyldimethylammonium bromide; b) Crystallizing, drying, and calcining the synthesis mother liquor obtained in step a) to obtain the SCM-40 molecular sieve; wherein, the phosphoaluminate precursor has a chemical composition shown by the formula "Al2O3:xP2O5", wherein 0.8 ≤ x ≤ 2; the XRD pattern of the phosphoaluminate precursor mainly includes the X-ray diffraction peaks shown in the following table: 。 6. The preparation method according to claim 5, characterized in that, In step a), the XRD pattern of the phosphoaluminate precursor further includes the X-ray diffraction peaks shown in the following table: 。 7. The preparation method according to claim 5, characterized in that, In step a), the XRD pattern of the phosphoaluminate precursor further includes the X-ray diffraction peaks shown in the following table: 。 8. The preparation method according to claim 5, characterized in that, In the synthesis mother liquor, the molar ratios of each material are as follows: the aluminum source A is calculated as Al2O3, the phosphorus source A is calculated as P2O5, the phosphoaluminate precursor is calculated as Al2O3, P2O5, the organic base R1, the organic compound R2, the fluorine source is calculated as HF, and water is calculated as H2O, (0.5 - 0.88)Al2O3:1P2O5:(0.3 - 0.8)R1:(1 - 2)R2:(0.5 - 1.8)HF:(50 - 130)H2O.

9. The preparation method according to claim 5, characterized in that, In the synthesis mother liquor, the molar ratios of each material are as follows: the aluminum source A is calculated as Al2O3, the phosphorus source A is calculated as P2O5, the phosphoaluminate precursor is calculated as Al2O3, P2O5, the organic base R1, the organic compound R2, the fluorine source is calculated as HF, and water is calculated as H2O, (0.5 - 0.85)Al2O3:1P2O5:(0.3 - 0.8)R1:(1 - 2)R2:(0.5 - 1.8)HF:(50 - 130)H2O.

10. The preparation method according to claim 5, characterized in that, The phosphorus source A is selected from at least one of phosphoric acid, ammonium monohydrogen phosphate, and ammonium dihydrogen phosphate; the aluminum source A is selected from one or more of pseudoboehmite, aluminum isopropoxide, aluminum sol, and alumina; the fluorine source is selected from HF aqueous solution.

11. According to the preparation method described in any one of claims 5-10, characterized in that, In step b), the crystallization conditions are as follows: the crystallization temperature is 120°C - 200°C, and the crystallization time is 8 - 100 hours.

12. The preparation method according to claim 11, characterized in that, In step b), the crystallization conditions are as follows: the crystallization temperature is 130°C - 190°C, and the crystallization time is 12 - 80 hours.

13. According to the preparation method described in any one of claims 5-10, characterized in that, In step b), the crystallization is carried out by a segmented crystallization method. The crystallization temperature in the first stage is 130°C - 190°C, and the crystallization time is 48 - 72 hours; the crystallization temperature in the second stage is 160°C - 200°C, and the crystallization time is 4 - 24 hours; wherein, the crystallization temperature in the second stage is at least 10°C higher than that in the first stage.

14. The preparation method according to claim 13, characterized in that, In step b), the crystallization is carried out by a segmented crystallization method. The crystallization temperature in the first stage is 130°C - 160°C, and the crystallization time is 24 - 72 hours; the crystallization temperature in the second stage is 170°C - 200°C, and the crystallization time is 5 - 18 hours; wherein, the crystallization temperature in the second stage is at least 20°C higher than that in the first stage.

15. The preparation method according to claim 5, characterized in that, The calcination conditions in step b) are as follows: the calcination temperature is 450°C - 650°C, and the calcination time is 1 - 8 hours.

16. The preparation method according to claim 15, characterized in that, The calcination conditions in step b) are as follows: the calcination temperature is 480°C - 550°C, and the calcination time is 3 - 5 hours.

17. An SCM-40 molecular sieve composition comprising the SCM-40 molecular sieve according to any one of claims 1 - 4 or the SCM-40 molecular sieve prepared by the preparation method according to any one of claims 5 - 16, and a binder.

18. The use of the SCM-40 molecular sieve according to any one of claims 1 - 4, or the SCM-40 molecular sieve prepared by the preparation method according to any one of claims 5 - 16, or the SCM-40 molecular sieve composition according to claim 17 in an adsorbent or a catalyst.

Images