Molecular sieve DNL-17 as well as preparation method and application thereof

Abstract

The invention discloses a molecular sieve DNL-17 as well as a preparation method and application thereof, and belongs to the field of chemical engineering. The invention relates to a molecular sieve DNL-17. The chemical composition of the molecular sieve is (H2O) xRy (SizAl72P72-zO288), wherein R is an organic template agent, and R is selected from 1, 3-(N-dimethyl ethyl) propane diammonium hydroxide; x is the mole number of H2O in each unit cell, and x is equal to 0-30.0; y is the mole number of the template agent in each unit cell and is equal to 8-10.0; z is the mole number of Si in each unit cell, and z is equal to 0-20.0; and the unit cell is (Si < z > Al < 72 > P < 72-z > O < 288 >). The molecular sieve has a novel three-dimensional 8 * 8 * 8-membered ring pore channel structure. The preparation method is simple in synthesis process and high in operability. The molecular sieve has catalysis and adsorption properties, can be used in a methanol-to-olefin catalytic reaction, and has a good application prospect.

Description

Technical Field

[0001] This application relates to a molecular sieve DNL-17, its preparation method, and its application, and belongs to the field of chemical engineering. Background Technology

[0002] Silicate aluminum molecular sieves and SAPO molecular sieves are commonly used industrial catalysts. Silicate aluminum phosphate molecular sieves (SAPO) belong to the aluminum phosphate molecular sieve family. SAPO molecular sieves can be understood as products obtained by isomorphous substitution in AlPO molecular sieves.

[0003] The synthesis of SAPO molecular sieves is similar to that of AlPO molecular sieves, generally through hydrothermal synthesis, although methods such as crystal transformation and microwave radiation synthesis also exist. Since R.M. Barrer and P.J. Denny introduced organic templates into the hydrothermal synthesis system of molecular sieves in 1961, the design, synthesis, and introduction of organic templates have greatly increased the quantity of artificially synthesized zeolites.

[0004] SAPO molecular sieves have a negatively charged framework, making them important for applications in adsorption separation and catalysis. For example, the Dalian Institute of Chemical Physics successfully used SAPO-34 as an industrial catalyst for DMTO to achieve coal-to-olefins conversion. Therefore, developing new SAPO molecular sieves has significant application implications. Summary of the Invention

[0005] In view of this, this application provides a novel molecular sieve with a framework structure, named DNL-17. This molecular sieve has a novel three-dimensional 8*8*8 membered ring channel structure, providing a new structural molecular sieve for the adsorption of phosphorus aluminum molecular sieves and the catalytic and adsorption properties of small-pore silica-phosphorus aluminum molecular sieves. The preparation method and application of molecular sieve DNL-17 are also provided.

[0006] According to the first aspect of this application, a molecular sieve DNL-17 is provided.

[0007] A molecular sieve, DNL-17, has the following chemical composition:

[0008] (H2O) x R y (Si z Al 72 P 72-z O 288 ) Formula I;

[0009] Wherein, R is an organic template agent, and R is selected from 1,3-(N-dimethylethyl)propane diammonium hydroxide;

[0010] x is the number of moles of H2O in each unit cell, x = 0 to 30.0;

[0011] y is the number of moles of template agent in each unit cell, y = 8 to 10.0;

[0012] z is the number of moles of Si in each unit cell, z = 0 to 20.0;

[0013] The unit cell is (Si) z Al 72 P 72-z O 288 ).

[0014] When z = 0, the molecular sieve is a phosphorus-aluminum molecular sieve; when z ≠ 0, the molecular sieve is a silicon-phosphorus-aluminum molecular sieve; when x = 0, it is the anhydrous chemical composition of the molecular sieve.

[0015] Optionally, x is selected from any value among 0, 1, 2, 5, 7, 10, 12, 15, 17, 20, 22, 25, 27, 28, and 30, or a range of values ​​between any two.

[0016] Optionally, y is selected from any value among 0, 8.2, 8.4, 8.5, 8.6, 8.7, 8.8, 9, 9.2, 9.4, 9.5, 9.6, 9.8, and 10, or a range between any two.

[0017] Optionally, z is selected from any value among 0, 0.5, 1, 1.5, 2, 2.2, 2.5, 2.7, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20 or a range of values ​​between any two.

[0018] Optionally, the unit cell parameters of the molecular sieve DNL-17 are:

[0019] Optionally, the X-ray powder diffraction of the molecular sieve DNL-17 has diffraction peaks at at least the following positions:

[0020]

[0021]

[0022] Optionally, the molecular sieve DNL-17 has three-dimensional 8*8*8 member annular channels.

[0023] Optionally, the molecular sieve DNL-17 has a blocky morphology with a size of 20 nm to 20 μm.

[0024] According to a second aspect of this application, a method for preparing molecular sieve DNL-17 is provided.

[0025] The preparation method of the molecular sieve DNL-17 described above includes the following steps:

[0026] The raw materials containing water, phosphorus source, aluminum source, silicon source, organic template agent R, mineralizer and alcohol solvent are mixed, some water is removed to obtain a mixture, which is placed in a sealed container and crystallized to obtain the molecular sieve DNL-17.

[0027] The molar ratio of the organic template agent, mineralizer, phosphorus source, silicon source, aluminum source, alcohol solvent, and water in the mixture is:

[0028] aR: bHF: cH3PO4: qSiO2: Al2O3: mTOH: nH2O;

[0029] Wherein, a = 0.5 to 2.0; the organic template agent R is selected from 1,3-(N-dimethylethyl)propane diammonium hydroxide, and its molar number is calculated based on the molar number of 1,3-(N-dimethylethyl)propane diammonium hydroxide itself;

[0030] b = 0 to 1.0; the number of moles of mineralizer is expressed in moles of HF;

[0031] c = 1.0–3.0; the number of moles of phosphorus source is expressed as the number of moles of H3PO4;

[0032] q = 0 to 0.4; the number of moles of silicon source is expressed as the number of moles of SiO2;

[0033] m = 0~100; the number of moles of the alcohol solvent is expressed as the number of moles of its own alcohol TOH;

[0034] n = 5 to 50; the number of moles of water is expressed as the number of moles of H2O.

[0035] When q = 0, that is, when no silicon source is added, the corresponding z = 0, the molecular sieve is a phosphorus-aluminum molecular sieve; when q ≠ 0, that is, when a silicon source is added, the molecular sieve is a silicon-phosphorus-aluminum molecular sieve.

[0036] When m = 0, no alcohol solvent is added.

[0037] In this application, a specific organic template agent, 1,3-(N-dimethylethyl)propane diammonium hydroxide, was selected to obtain a molecular sieve, DNL-17, with a novel three-dimensional 8*8*8 membered ring channel structure.

[0038] In this application, since the raw materials phosphorus source, aluminum source, silicon source, organic template agent R and mineralizing agent HF usually contain water, after the raw materials are mixed, some of the water needs to be removed to obtain a mixture gel. The method for removing some of the water can be a water bath.

[0039] Optionally, the molar ratio α of the organic template agent is selected from any value or a range between 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0.

[0040] Optionally, the molar ratio b of the mineralizer is selected from any value of 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 or a range between any two.

[0041] Optionally, the molar ratio c of the phosphorus source is selected from any value or a range between 1.0, 1.2, 1.3, 1.5, 1.7, 1.8, 2.0, 2.1, 2.2, 2.4, 2.5, 2.6, 2.8, and 3.0.

[0042] Optionally, the molar ratio q of the silicon source is selected from any value of 0, 0.1, 0.2, 0.3, 0.4 or any range between two values.

[0043] Optionally, the molar ratio m of the alcohol solvent is selected from any value among 0, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, and 100, or a range between any two.

[0044] Optionally, the molar ratio n of water is selected from any value of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 or a range between any two.

[0045] Optionally, the alcohol solvent is selected from at least one of cyclohexanol, ethylene glycol, diethylene glycol, and triethylene glycol.

[0046] Optionally, the phosphorus source is selected from at least one of phosphoric acid and phosphorus pentoxide.

[0047] The aluminum source is selected from at least one of boehmite, aluminum hydroxide, and aluminum isopropoxide.

[0048] The silicon source is selected from at least one of silica sol, tetraethyl orthosilicate, tetramethoxysilane, and silica.

[0049] Optionally, the crystallization temperature is 130–200°C, and the crystallization time is 1–15 days.

[0050] Optionally, the crystallization temperature is selected from any value of 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, and 200°C, or a range between any two.

[0051] Optionally, the crystallization time is selected from any value of 1d, 2d, 3d, 4d, 5d, 6d, 7d, 8d, 9d, 10d, 12d, 13d, 14d, 15d or a range between any two.

[0052] Optionally, the raw materials containing water, phosphorus source, aluminum source, silicon source, organic template agent, mineralizer and alcohol solvent are mixed, including:

[0053] First, mix the phosphorus source and alcohol solvent, then add the aluminum source and silicon source, then add the organic template agent R, then add the mineralizer, and stir to mix.

[0054] or

[0055] First, mix the phosphorus source and the organic template agent R, then add the aluminum source and stir to mix.

[0056] Optionally, after crystallization, the solid product is centrifuged, washed, and dried to obtain the molecular sieve DNL-17. It is a white powder product, and the product retaining the organic template agent is usually referred to as the molecular sieve raw powder. In practical applications, the organic template agent can be removed by calcination as needed.

[0057] Optionally, the roasting temperature is 500–600°C, and the roasting time is 3–7 hours.

[0058] According to a third aspect of this application, the application of the aforementioned molecular sieve DNL-17 in adsorption separation is provided.

[0059] The application of the molecular sieve DNL-17 described above in adsorption separation.

[0060] Optionally, the molecular sieve DNL-17 can be used after calcination to remove the organic template agent.

[0061] Optionally, the application is the adsorption separation of n-isobutane.

[0062] According to the fourth aspect of this application, the use of the molecular sieve DNL-17 described above as a catalyst is provided.

[0063] The aforementioned molecular sieve DNL-17 is used as a catalyst.

[0064] Optionally, the molecular sieve DNL-17 can be used after calcination to remove the organic template agent.

[0065] Optionally, the application is a methanol-to-olefins catalytic reaction.

[0066] The beneficial effects that this application can produce include:

[0067] This application provides the molecular sieve DNL-17, its preparation method, and its applications. This molecular sieve possesses a novel three-dimensional 8*8*8 membered ring channel structure. The synthesis method is simple and highly operable. This molecular sieve, DNL-17, exhibits catalytic and adsorption properties and has promising applications in methanol-to-olefins catalytic reactions. Attached Figure Description

[0068] Figure 1 This is the X-ray powder diffraction (XRD) pattern of the product obtained in Example 1 of this application.

[0069] Figure 2 This is a scanning electron microscope (SEM) image of the product obtained in Example 1 of this application, with a scale of 500 nm. Detailed Implementation

[0070] The present application is further illustrated below with reference to specific embodiments. The following descriptions are merely a few embodiments of the present application and are not intended to limit the present application in any way. Although the present application discloses preferred embodiments as follows, they are not intended to limit the present application. Any modifications or variations made by those skilled in the art without departing from the scope of the technical solution of the present application using the disclosed technical content are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

[0071] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0072] The analysis method in the embodiments of this application is as follows:

[0073] Phase analysis of the samples was performed using X-ray powder diffraction (XRD) with a Cu target and a Kα light source. The instrument used was an X'Pert PRO X-ray diffractometer from PANalytical, Netherlands. Tested under conditions of 40KV voltage and 40mA current.

[0074] The sample structure was analyzed using continuous rotating electron diffraction (cRED) with a JEOL 2100Plus transmission electron microscope equipped with an EMSIS GmbH camera and an ASI Cheetah 120 detector.

[0075] The composition of the samples was analyzed by X-ray fluorescence spectroscopy (XRF) on a Philips Magix-601 X-ray fluorescence spectrometer.

[0076] Sample morphology analysis was performed using a scanning electron microscope (SEM) with the instrument being a Hitachi SU8020 field emission scanning electron microscope.

[0077] The samples were thermally analyzed using a TAQ-600 thermal analyzer at a heating rate of 10℃ / min from room temperature to 900℃.

[0078] In the embodiments of this application, the conversion rate and selectivity are calculated as follows:

[0079] In the embodiments of this application, the methanol conversion rate and the selectivity of ethylene and propylene are calculated based on the number of carbon moles:

[0080] The formula for calculating methanol conversion rate is:

[0081]

[0082] In the formula, A is the methanol peak area measured during the reaction, and B is the methanol peak area measured when no catalyst is loaded.

[0083] The formula for calculating the selectivity of low-carbon olefins is as follows:

[0084]

[0085] In the formula, n is the number of carbons corresponding to the low carbon olefin, C is the peak area of ​​the low carbon olefin measured in the reaction, and M is the number of carbons of all products multiplied by the peak area measured in their respective reactions.

[0086] Example 1: Preparation of Sample 1

[0087] 0.218 g of orthophosphoric acid (85%) was added to 4.155 g of triethylene glycol and stirred. Then, 0.381 g of aluminum triisopropoxide (98%) was added and stirred until homogeneous. Next, 1.765 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%) was added and stirred vigorously (500 rpm) until homogeneous. 1.5 g of water was then removed by water bath. The molar ratio of organic template agent, phosphorus source, aluminum source, alcohol solvent, and water in the mixture was 1R:2H3PO4:Al2O3:30TOH:5H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200 °C for 144 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed, and dried in air at 100 °C to obtain a white powder product, named DNL-17, and designated as sample 1.

[0088] The X-ray powder diffraction (XRD) pattern of sample 1 is as follows: Figure 1 As shown in Table 1, the X-ray powder diffraction characteristics show three peaks in the first ten degrees; the scanning electron microscope (SEM) images are shown below. Figure 2 As shown, sample 1 has a blocky morphology with a size ranging from 20 nm to 20 μm. Furthermore, the SEM image shows a uniform morphology of the molecular sieve, indicating that the synthesized molecular sieve does not contain other phases, demonstrating high purity. XRF analysis and thermal analysis, after normalization, yielded the elemental composition of sample 1 as: (H₂O).28.7 R 8.7 (Al 72 P 72 O 288 ), where R is 1,3-(N-dimethylethyl)propane diammonium hydroxide cation.

[0089] Table 1. X-ray powder diffraction characteristics of sample 1

[0090]

[0091]

[0092]

[0093] Example 2: Preparation of Sample 2

[0094] 0.21 g of orthophosphoric acid (85%) was added to 4.151 g of triethylene glycol and stirred. Then, 0.382 g of aluminum triisopropoxide (98%) and 0.023 g of silica sol were added and stirred until homogeneous. Then, 1.755 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%) was added and stirred vigorously (500 rpm) until homogeneous. 1.5 g of water was removed by water bath. The molar ratio of organic template agent, phosphorus source, silicon source, aluminum source, alcohol solvent and water in the mixture was 1R:2H3PO4:0.2SiO2:Al2O3:30TOH:5H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200 °C for 156 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed and dried in air at 100 °C to obtain a white powder product.

[0095] The product was identified as SAPO-DNL-17 by X-ray powder diffraction and is designated as sample 2.

[0096] The X-ray powder diffraction pattern (XRD) and scanning electron microscope (SEM) images of sample 2 are similar to those of sample 1.

[0097] The elemental composition of sample 2 is: (H2O) 28 R 8.8 (Si 2.7 Al 72 P 69.3 O 288 ), where R is 1,3-(N-dimethylethyl)propane diammonium hydroxide cation.

[0098] Example 3: Preparation of Sample 3

[0099] 0.22 g of orthophosphoric acid (85%) was added to 2.965 g of diethylene glycol and stirred. Then, 0.381 g of aluminum triisopropoxide (98%) was added and stirred until homogeneous. Next, 1.758 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%) was added and stirred vigorously (500 rpm) until homogeneous. 1.5 g of water was removed by water bath. The molar ratio of organic template agent, phosphorus source, aluminum source, alcohol solvent, and water in the mixture was 1R:2H3PO4:Al2O3:30TOH:5H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200 °C for 144 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed, and dried in air at 100 °C to obtain a white powder product.

[0100] The product was confirmed to be DNL-17 by X-ray powder diffraction and is designated as sample 3.

[0101] The X-ray powder diffraction pattern (XRD) and scanning electron microscope (SEM) images of sample 3 are similar to those of sample 1.

[0102] Example 4: Preparation of Sample 4

[0103] 0.218 g of orthophosphoric acid (85%) was added to 1.724 g of ethylene glycol and stirred. Then, 0.38 g of aluminum triisopropoxide (98%) was added, followed by 1.73 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%). The mixture was stirred vigorously (500 rpm) until homogeneous, and 1.5 g of water was removed by water bath. The molar ratio of organic template agent, phosphorus source, aluminum source, alcohol solvent, and water in the mixture was 1R:2H3PO4:Al2O3:30TOH:5H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200 °C for 240 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed, and dried in air at 100 °C to obtain a white powder product.

[0104] The product was identified as DNL-17 by X-ray powder diffraction and was designated as sample 4.

[0105] The X-ray powder diffraction pattern (XRD) and scanning electron microscope (SEM) images of sample 4 are similar to those of sample 1.

[0106] Example 5: Preparation of Sample 5

[0107] 0.219 g of orthophosphoric acid (85%) was added to 1.724 g of triethylene glycol and stirred. Then, 0.381 g of aluminum triisopropoxide (98%) was added, followed by 1.753 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%), and 0.01 g of HF mineralizer. The mixture was stirred vigorously (500 rpm) until homogeneous, and 1.5 g of water was removed by water bath. The molar ratio of organic template agent, mineralizer, phosphorus source, aluminum source, alcohol solvent, and water in the mixture was 1R:0.2HF:2H3PO4:Al2O3:30TOH:5H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200 °C for 140 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed, and dried in air at 100 °C to obtain a white powder product.

[0108] The product was confirmed to be DNL-17 by X-ray powder diffraction and is designated as sample 5.

[0109] The X-ray powder diffraction pattern (XRD) and scanning electron microscope (SEM) images of sample 5 are similar to those of sample 1.

[0110] Preparation of Sample 6 in Example 6

[0111] 0.215 g of orthophosphoric acid (85%) was added to 1.76 g of 1,3-(N-dimethylethyl)propane diammonium hydroxide (11%) and mixed. Then, 0.38 g of aluminum triisopropoxide (98%) was added and vigorously stirred (500 rpm) until homogeneous. 0.92 g of water was removed by water bath. The molar ratio of the organic template agent, phosphorus source, aluminum source, and water in the mixture was 1R:2H3PO4:Al2O3:40H2O. The mixture was transferred to a stainless steel high-pressure reactor and statically crystallized at 200°C for 72 hours under autogenous pressure. After crystallization, the solid product was centrifuged, washed, and dried in air at 100°C to obtain a white powder product.

[0112] The product was identified as DNL-17 by X-ray powder diffraction and was designated as sample 6.

[0113] The X-ray powder diffraction pattern (XRD) and scanning electron microscope (SEM) images of sample 6 are similar to those of sample 1.

[0114] Example 7 Structural Analysis

[0115] Continuous rotational electron diffraction (cRED) was performed on samples 1-4. Taking sample 1 as an example, its structural analysis results show that the unit cell parameters of the molecular sieve DNL-17 are: Furthermore, the DNL-17 has a three-dimensional 8*8*8 channel.

[0116] Application Example 1: DNL-17 used in catalysis

[0117] This application example illustrates the use of DNL-17 in the methanol-to-olefins (MTO) catalytic reaction.

[0118] Sample 2 obtained in Example 2 was calcined to remove the template agent. The calcination temperature was 550°C and the calcination time was 4 hours, which served as a catalyst.

[0119] The catalyst was loaded into a fixed-bed reactor for MTO catalysis testing. 0.1 g of catalyst was weighed and loaded into the reaction tube. Under N2 purging, the temperature was programmed to rise to 500 °C for 30 min for activation, then cooled to 450 °C, and methanol was introduced at a mass hourly space velocity (WHSV) of 2 h⁻¹. -1 .

[0120] Sample 2 corresponds to a methanol conversion rate of 99.8%, an ethylene selectivity of 17%, and a propylene selectivity of 30%.

[0121] Application Example 2: DNL-17 for Adsorption Separation

[0122] This application example illustrates the use of DNL-17 for the adsorption and separation of n-isobutane. Sample 1 obtained in Example 1 was calcined to remove the template agent at a temperature of 550°C for 4 hours. The sample was then loaded into an adsorption analyzer for adsorption testing at 25°C.

[0123] The n-butane adsorption capacity of sample 1 is 42 cm⁻¹. 3 / g, isobutane adsorption capacity 3cm 3 / g.

[0124] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A molecular sieve DNL-17, characterized in that, The chemical composition of the molecular sieve is as follows: (H2O) x R y (Si z Al 72 P 72-z O 288 ) Formula I; Wherein, R is an organic template agent, and R is selected from 1,3-(N-dimethylethyl)propane diammonium hydroxide; x is the number of moles of H2O in each unit cell, x = 0 to 30.0; y is the number of moles of template agent in each unit cell, y = 8 to 10.0; z is the number of moles of Si in each unit cell, z = 0 to 20.0; The unit cell is (Si) z Al 72 P 72-z O 288 ).

2. The molecular sieve DNL-17 according to claim 1, characterized in that, The unit cell parameters of the molecular sieve DNL-17 are as follows:

3. The molecular sieve DNL-17 according to claim 1, characterized in that, The molecular sieve DNL-17 exhibits diffraction peaks at at least the following positions in X-ray powder diffraction:

4. The molecular sieve DNL-17 according to claim 1, characterized in that, The molecular sieve DNL-17 has a three-dimensional 8*8*8 member ring channel; Preferably, the molecular sieve DNL-17 has a blocky morphology and a size of 20 nm to 20 μm.

5. The method for preparing the molecular sieve DNL-17 according to any one of claims 1-4, characterized in that, Includes the following steps: The raw materials containing water, phosphorus source, aluminum source, silicon source, organic template agent R, mineralizer and alcohol solvent are mixed, some water is removed to obtain a mixture, which is placed in a sealed container and crystallized to obtain the molecular sieve DNL-17. The molar ratio of the organic template agent, mineralizer, phosphorus source, silicon source, aluminum source, alcohol solvent, and water in the mixture is: aR: bHF: cH3PO4: qSiO2: Al2O3: mTOH: nH2O; Wherein, a = 0.5 to 2.0; the organic template agent R is selected from 1,3-(N-dimethylethyl)propane diammonium hydroxide, and its molar number is calculated based on the molar number of 1,3-(N-dimethylethyl)propane diammonium hydroxide itself; b = 0 to 1.0; the number of moles of mineralizer is expressed in moles of HF; c = 1.0–3.0; the number of moles of phosphorus source is expressed as the number of moles of H3PO4; q = 0 to 0.4; the number of moles of silicon source is expressed as the number of moles of SiO2; m = 0~100; the number of moles of the alcohol solvent is expressed as the number of moles of its own alcohol TOH; n = 5 to 50; the number of moles of water is expressed as the number of moles of H2O.

6. The preparation method according to claim 5, characterized in that, The alcohol solvent is selected from at least one of cyclohexanol, ethylene glycol, diethylene glycol, and triethylene glycol; Preferably, the phosphorus source is selected from at least one of phosphoric acid and phosphorus pentoxide; The aluminum source is selected from at least one of boehmite, aluminum hydroxide, and aluminum isopropoxide. The silicon source is selected from at least one of silica sol, tetraethyl orthosilicate, tetramethoxysilane, and silica.

7. The preparation method according to claim 5, characterized in that, The crystallization temperature is 130–200°C, and the crystallization time is 1–15 days.

8. The preparation method according to claim 5, characterized in that, The raw materials containing water, phosphorus source, aluminum source, silicon source, organic template agent, mineralizer and alcohol solvent are mixed, including: First, mix the phosphorus source and alcohol solvent, then add the aluminum source and silicon source, then add the organic template agent R, then add the mineralizer, and stir to mix. or First, mix the phosphorus source and the organic template agent R, then add the aluminum source and stir to mix.

9. The application of the molecular sieve DNL-17 according to any one of claims 1-4 in adsorption separation; Preferably, the molecular sieve DNL-17 is used after calcination to remove the organic template agent; Preferably, the application is the adsorption and separation of n-isobutane.

10. The use of the molecular sieve DNL-17 according to any one of claims 1-4 as a catalyst; Preferably, the molecular sieve DNL-17 is used after calcination to remove the organic template agent; Preferably, the application is a methanol-to-olefins catalytic reaction.

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