SCM-47 molecular sieve as well as preparation method and application thereof

Abstract

The invention provides an SCM-47 molecular sieve as well as a preparation method and application thereof. An X-ray diffraction spectrum of the SCM-47 molecular sieve comprises one or more of diffraction peaks with 2theta being 7.08 degrees + / -0.30 degrees, 8.68 degrees + / -0.30 degrees, 13.08 degrees + / -0.30 degrees and 15.78 degrees + / -0.30 degrees, and preferably, the diffraction peak with 2theta being 8.68 degrees + / -0.30 degrees is the strongest peak. The framework of the SCM-47 molecular sieve contains Si element and other optional elements, and the SCM-47 molecular sieve has the advantages of lamellar morphology, high specific surface area, large micropore volume and excellent adsorption and catalytic performance.

Description

Technical Field

[0001] This invention relates to the field of porous materials technology, specifically to an SCM-47 molecular sieve, its preparation method, and its applications. Background Technology

[0002] The structural characteristics of molecular sieves determine their performance and applications, and expanding the diversity of molecular sieve structures helps to improve their existing performance. In silicon-germanium molecular sieves, Ge atoms generally preferentially reside in the double four-membered ring (D4R) structural unit. Utilizing the instability of the Ge-O bond and its easy breakage upon contact with water, germanium-rich D4R units can be directionally removed, transforming the parent molecular sieve into a new one. Compared with traditional hydrothermal synthesis, this topological transformation strategy has the following advantages: 1) The derived molecular sieve has a structural correlation with the parent molecular sieve, thus its structure can be predicted; while traditional hydrothermal synthesis is based on trial and error, and the structure of the molecular sieve product is unpredictable; 2) The energy of the derived molecular sieve may be higher than that of the parent molecular sieve, which cannot be obtained using traditional hydrothermal synthesis.

[0003] In existing technologies, UTL molecular sieves are used as the parent material, and various derivative molecular sieves such as IPC-2, IPC-4, and IPC-6 can be obtained by utilizing this topological transformation strategy. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an SCM-47 molecular sieve, its preparation method, and its application.

[0005] In a first aspect, the present invention provides an SCM-47 molecular sieve, the X-ray diffraction pattern of which includes one or more diffraction peaks with 2θ of 7.08°±0.30°, 8.68°±0.30°, 13.08°±0.30°, and 15.78°±0.30°.

[0006] In some implementations, the diffraction peak with 2θ of 8.68°±0.30° is the strongest peak.

[0007] In some embodiments, the X-ray diffraction pattern of the SCM-47 molecular sieve further includes one or more diffraction peaks with 2θ values ​​of 19.90°±0.30°, 21.87°±0.30°, 23.42°±0.30°, 24.96°±0.30°, 26.46°±0.30°, and 28.00°±0.30°.

[0008] In some embodiments, the X-ray diffraction pattern of the SCM-47 molecular sieve includes the X-ray diffraction peaks shown in Table A:

[0009] Table A

[0010]

[0011]

[0012] In some embodiments, the X-ray diffraction pattern of the SCM-47 molecular sieve also includes the X-ray diffraction peaks shown in Table B:

[0013] Table B

[0014]

[0015] In some embodiments, the X-ray diffraction pattern of the SCM-47 molecular sieve includes the X-ray diffraction peaks shown in Table C:

[0016] Table C

[0017]

[0018] In some embodiments, the X-ray diffraction pattern of the SCM-47 molecular sieve also includes the X-ray diffraction peaks shown in Table D:

[0019] Table D

[0020]

[0021]

[0022] In this invention, in the X-ray diffraction pattern, vw, w, m, s, and vs represent the diffraction peak intensities, where vw indicates very weak, w indicates weak, m indicates moderate, s indicates strong, and vs indicates very strong. Generally, vw indicates less than 5%, w indicates 5%-20%, m indicates 20%-40% (inclusive), s indicates 40%-70%, and vs indicates 70% or more (inclusive).

[0023] Since the strength is affected by various factors, the data in the table represent the interplanar spacing of SCM-47 molecular sieve at 2θ (°) of 7.08 ± 0.3. The value is 12.47 ± 0.45, and the relative strength (%) (I / I0) × 100 is vw-w (0%-20%). And so on. Those skilled in the art are familiar with the representation methods of this table, and the present invention will not describe them one by one.

[0024] In some embodiments, the SCM-47 molecular sieve comprises SiO2 and GeO2, wherein the molar ratio of SiO2 to GeO2 is 50 or more, for example, it can be 50, 55, 60, 65, 70, 75, 80, 200, 400, 600, 800, 1000, or +∞. When the molar ratio of SiO2 to GeO2 is +∞, SCM-47 is a pure silicon molecular sieve.

[0025] In some implementations, the molar ratio of SiO2 to GeO2 is 65 or higher.

[0026] In some implementations, the molar ratio of SiO2 to GeO2 is 65-200.

[0027] In some embodiments, the SCM-47 molecular sieve further includes MO. m / 2 Where M is a framework element other than silicon, m is the valence of element M, and m = 1 to 7. (SiO2 and MO) m / 2 The molar ratio is 20 or higher, for example, it can be 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 400, 600, 800, 1000, or +∞. This applies when the molar ratio of SiO2 to GeO2 is +∞ and when the molar ratio of SiO2 to Mo2O2 is +∞. m / 2 When the molar ratio is +∞, SCM-47 is a pure silicon molecular sieve.

[0028] In some implementations, SiO2 and MO m / 2 The molar ratio is 50-200.

[0029] In some embodiments, the framework element M of the SCM-47 molecular sieve, excluding silicon, is selected from at least one of Group IIIA, Group IVA, Group IVB, Group IIB, Group VIB, Group VIIB, Group IA, Group IIA, Group VIII, Group VA, or Group VB elements, and preferably from at least one of aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, vanadium, cobalt, nickel, arsenic, or antimony.

[0030] The oxidation state of element M is m, where m = 1 to 7, rounded to the nearest integer. For example, when M is lithium, its oxidation state is +1, m = 1; when M is magnesium, its oxidation state is +2, m = 2; when M is aluminum, its oxidation state is +3, m = 3; when M is germanium, its oxidation state is +4, m = 4; when M is vanadium, its oxidation state is +5, m = 5; when M is chromium, its oxidation state is +6, m = 6; and when M is manganese, its oxidation state is +7, m = 7.

[0031] This invention generates different catalytic active centers in high-silicon SCM-47 molecular sieves by introducing a non-silicon framework element M, which can meet the needs of different catalytic reactions.

[0032] In some embodiments, the SCM-47 molecular sieve comprises a plate-like crystal morphology.

[0033] In some embodiments, the thickness of the SCM-47 molecular sieve sheets is 20 to 500 nm, for example, 20 nm, 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm or any value between them.

[0034] In some embodiments, the specific surface area of ​​the SCM-47 molecular sieve is greater than 150 m². 2 / g.

[0035] In some embodiments, the specific surface area of ​​the SCM-47 molecular sieve is 160-500 m². 2 / g, for example, 170m 2 / g、190m 2 / g、210m 2 / g、220m 2 / g、230m 2 / g、240m 2 / g、250m 2 / g、260m 2 / g、270m 2 / g、280m 2 / g、290m 2 / g、300m 2 / g, 350m 2 / g、400m 2 / g、500m 2 / g or any value in between.

[0036] In some embodiments, the specific surface area of ​​the SCM-47 molecular sieve is 180-450 m². 2 / g.

[0037] In some embodiments, the specific surface area of ​​the SCM-47 molecular sieve is 180-400 m². 2 / g.

[0038] In some embodiments, the micropore volume of the SCM-47 molecular sieve is greater than 0.07 cm³. 3 / g.

[0039] In some embodiments, the micropore volume of the SCM-47 molecular sieve is 0.075-0.25 cm³. 3 / g, for example, 0.08cm 3 / g, 0.081cm 3 / g, 0.082cm 3 / g, 0.084cm 3 / g, 0.086cm 3 / g, 0.088cm 3 / g, 0.09cm 3 / g, 0.092cm 3 / g, 0.094cm 3 / g, 0.096cm 3 / g, 0.1cm 3 / g, 0.15cm 3 / g, 0.2cm 3 / g or any value in between.

[0040] In some embodiments, the micropore volume of the SCM-47 molecular sieve is 0.075-0.15 cm³. 3 / g.

[0041] In some embodiments, the micropore volume of the SCM-47 molecular sieve is 0.08-0.15 cm³. 3 / g.

[0042] In some embodiments, the SCM-47 includes a layered structure and interlayer connecting units, the interlayer connecting units including a single four-membered ring and an oxygen atom.

[0043] In some embodiments, the molar ratio of the single four-membered ring to the oxygen atom is 1:2 to 2:1, for example, 1:2, 1:1.5, 1:1, 1.5:1, 2:1 or any value between them.

[0044] In some embodiments, the molar ratio of the single four-membered ring to the oxygen atom is 1:1.

[0045] In this invention, SCM-47 has a dense silicon-rich layer. XRD analysis shows that the interlayer bonding units consist of single four-membered rings and oxygen atoms in an approximately 1:1 ratio. The topology of SCM-47 is as follows: Figure 1 As shown.

[0046] In a second aspect, the present invention provides a method for preparing SCM-47 molecular sieve, comprising the following steps: contacting a molecular sieve precursor with a treatment liquid and reacting therewith.

[0047] In some embodiments, the Si / Ge ratio in the molecular sieve precursor is ≤5.5.

[0048] In some embodiments, the reaction temperature is between 5°C and 40°C, for example, 5°C, 7.5°C, 10°C, 12.5°C, 15°C, 17.5°C, 20°C, 25°C, 30°C, 35°C, 40°C or any value between them;

[0049] In some embodiments, the reaction time is 5 min to 15 h, for example, 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 1 h, 5 h, 10 h, 15 h or any value between them.

[0050] The contact method between the molecular sieve precursor and the treatment liquid in this invention can be direct contact or indirect contact. Direct contact generally refers to immersing the molecular sieve precursor in the treatment liquid and allowing it to react through standing or stirring. Indirect contact generally refers to placing the molecular sieve precursor above the treatment liquid, where the vapors evaporating from the treatment liquid react with the molecular sieve precursor, such as... Figure 2 As shown.

[0051] The molecular sieve precursor SCM-47P has an IWV topology, and its framework can be considered as consisting of a dense silicon-rich layer in the bc plane and germanium-rich double four-membered ring structural units connecting the layers along the a-axis. SCM-47 can be regarded as a derivative structure of SCM-47P. Compared with SCM-47P, the dense silicon-rich layer of SCM-47 remains unchanged, but the interlayer connecting units are changed from double four-membered rings to single four-membered rings and oxygen atoms, with a ratio of approximately 1:1.

[0052] In some embodiments, the preparation method of SCM-47 molecular sieve further includes: post-reaction processing, which includes solid-liquid separation, washing, drying and calcination.

[0053] After the processing steps described in this invention are completed, the molecular sieve can be separated from the mixture by any conventionally known separation method. Examples of such separation methods include filtration or centrifugation of the mixture. Filtration and centrifugation can be performed in any manner conventionally known in the art. Specifically, for example, filtration can be performed by simply vacuum filtering the mixture. Washing and drying in this invention can be performed in any manner conventionally known in the art. Specifically, for example, washing can be performed using deionized water. 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 performed under normal pressure or under reduced pressure.

[0054] The present invention involves calcining the molecular sieve precursor to remove any present moisture, etc. The calcination can be carried out in any manner conventionally known in the art; for example, the calcination temperature is generally 300-800℃, preferably 400-650℃, and the calcination time is generally 1-10 hours, preferably 3-6 hours. Furthermore, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0055] In some embodiments, the mass ratio of the treatment liquid to the molecular sieve precursor is 20-300, for example, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80, 90, 100, 150, 200, 250, 300 or any value between them.

[0056] In some embodiments, the mass ratio of the treatment liquid to the molecular sieve precursor is 30-100.

[0057] In some embodiments, the treatment solution is selected from at least one of an acid solution, an alkaline solution, or an aqueous solution of the M' source.

[0058] In some embodiments, the acid solution is selected from at least one of HCl aqueous solution, HCl alcoholic solution, H2SO4 aqueous solution, HNO3 aqueous solution, acetic acid solution, and ammonia aqueous solution, preferably HCl aqueous solution.

[0059] In some embodiments, the HCl alcohol solution may include, for example, a methanol solution of HCl, an ethanol solution of HCl, or an isopropanol solution of HCl.

[0060] In some embodiments, the concentration of the acid solution is 0.01-20M, for example 0.01M, 0.1M, 1M, 2M, 3M, 6M, 9M, 12M or any value between them.

[0061] In some embodiments, the concentration of the acid solution is 0.01-14M.

[0062] In some embodiments, the concentration of the HCl aqueous solution may be, for example, 0.01M, 0.1M, 1M, 2M, 3M, 6M, 9M, 12M, etc.

[0063] In some embodiments, the concentration of the HNO3 aqueous solution may be, for example, 0.01M, 0.1M, 1M, 2M, 3M, 6M, 8M, 10M, 12M, 14M, etc.

[0064] In some embodiments, the alkaline solution is an aqueous ammonia solution.

[0065] In some embodiments, the concentration of the alkaline solution is 0.1-30 wt%, for example, 0.5 wt%, 1 wt%, 2 wt%, 5 wt%, 10 wt%, 15 wt%, 25 wt%, or any value between them.

[0066] In some embodiments, the concentration of the alkaline solution is 0.5-25 wt%.

[0067] In some embodiments, the concentration of the ammonia solution can be 0.5wt%, 1wt%, 2wt%, 5wt%, 10wt%, 15wt%, 25wt%, etc.

[0068] When the treatment solution is an aqueous solution of the M' source, the M' source will enter the molecular sieve framework and form SiO2, GeO2 and MO with the silicon source, germanium source and M source. m / 2 Molecular sieves, where M is a framework element excluding silicon, m is the valence of element M, m = 1 to 7, and SiO2 and MO... m / 2 When the molar ratio is above 20, MO m / 2 M in M ​​includes elements from both the source M and the source M'.

[0069] In some embodiments, the M' source in the aqueous solution of the M' source is selected from at least one water-soluble compound of a group IIIA element, group IVA element, group IVB element, group IIB element, group VIB element, group VIIB element, group IA element, group IIA element, group VIII element, group VA element, or VB element.

[0070] In some embodiments, the M' source in the aqueous solution of the M' source is selected from at least one of water-soluble compounds of aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, cobalt, nickel, arsenic, and antimony.

[0071] In some embodiments, the water-soluble compound is at least one of chloride, fluoride, sulfate, nitrate or acetate.

[0072] In some preferred embodiments, the M' source in the aqueous solution of the M' source is selected from water-soluble aluminum compounds, water-soluble titanium compounds, and water-soluble iron compounds.

[0073] In some embodiments, the water-soluble aluminum compound is selected from at least one of aluminum chloride, aluminum sulfate, aluminum nitrate, and aluminum acetate. In some preferred embodiments, the water-soluble titanium compound is selected from at least one of titanium tetrachloride, titanium sulfate, and ammonium hexafluorotitanate. In some preferred embodiments, the water-soluble iron compound is selected from ferric chloride, ferric sulfate, ferric nitrate, etc. In some preferred embodiments, the M' source is selected from aluminum nitrate and / or ammonium hexafluorotitanate.

[0074] In some preferred embodiments, the water-soluble compounds of boron, gallium, indium, germanium, tin, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, phosphorus, cobalt, nickel, arsenic, and antimony are all conventionally used in the art, such as nitrates.

[0075] In some embodiments, when the treatment liquid is HCl vapor, the reaction time needs to be extended to 5-10 hours.

[0076] In some implementations, when the silicon-germanium ratio of the molecular sieve precursor is greater than 4, the higher the mass ratio of the treatment liquid to the molecular sieve precursor, the longer the reaction time.

[0077] When the silicon-germanium ratio of the molecular sieve precursor is greater than 4, and the mass ratio of the treatment liquid to the molecular sieve precursor is 80-150, the reaction time is 5-15 hours.

[0078] In some embodiments, the method for preparing the molecular sieve precursor includes: subjecting a mixture comprising a silicon source, a germanium source, an M source, a fluorine source, a structure directing agent, and water to a crystallization reaction.

[0079] In some embodiments, the present invention does not impose specific limitations on the preparation method of the SCM-47 molecular sieve precursor. For example, a germanium source can be mixed with a structure-directing agent and water first, and then an M source and a silicon source can be added sequentially, followed by the addition of a fluorine source to obtain the mixture.

[0080] In some embodiments, the molar ratio of SiO2 to GeO2 in the mixture is (2-3.5):1, for example 2:1, 2.25:1, 2.5:1, 2.75:1, 3:1, 3.25:1, 3.5:1 or any value between them.

[0081] In some embodiments, the number of moles of silicon source is SiO2, the number of moles of germanium source is GeO2, and the sum of the number of moles of SiO2 and GeO2 in the mixture is 1.

[0082] In some embodiments, the molar number of the silicon source is SiO2, the molar number of the germanium source is GeO2, and the molar number of the M source is MO. m / 2 The sum of the molar numbers of SiO2 and GeO2 in the mixture is calculated to be equal to the molar number of MO. m / 2 The ratio of the number of moles is (15 to 30):1, for example, 15:1, 20:1, 25:1, 30:1 or any value between them.

[0083] In some embodiments, the molar number of the silicon source is SiO2, the molar number of the germanium source is GeO2, and the molar number of the fluorine source is F. In the mixture, the molar ratio of the sum of the molar numbers of SiO2 and GeO2 to F is 1:(0.1-1), for example, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, or 1:1; preferably 1:0.5.

[0084] In some embodiments, the molar number of the silicon source is SiO2, the molar number of the germanium source is GeO2, and the molar ratio of the sum of the molar numbers of SiO2 and GeO2 to the structure directing agent in the mixture is 1:(0.1-1), for example 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1; preferably 1:0.5.

[0085] In some embodiments, the number of moles of silicon source is SiO2, the number of moles of germanium source is GeO2, and the molar ratio of the sum of the moles of SiO2 and GeO2 to water in the mixture is 1:(12.5-25), for example 1:12.5, 1:14, 1:16, 1:18, 1:20, 1:25 or any value between them.

[0086] In some embodiments, the mixture contains a structure-directing agent, SiO2, GeO2, and MO. m / 2 The molar ratio of F to water is 0.5:(0.667-0.778):(0.222-0.333):(0.0333-0.0667):0.5:(12.5-25).

[0087] In some embodiments, the silicon source is selected from at least one group consisting of water glass, silica sol, solid silica gel, fumed silica, amorphous silica, diatomaceous earth, zeolite molecular sieve, and tetraalkoxysilane.

[0088] In some embodiments, the germanium source is selected from at least one of germanium oxide, germanium nitrate, and tetraalkoxy germanium.

[0089] In some preferred embodiments, the M source is selected from at least one of the following: elemental form, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt of group IIIA, group IVA, group IVB, group IIB, group VIB, group VIIB, group IA, group IIA, group VIII, group VA, or group VB elements.

[0090] In some embodiments, the M source is selected from at least one of the following: elemental form, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt of aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, vanadium, cobalt, nickel, arsenic, or antimony. In some preferred embodiments, the M source is selected from at least one of the following: elemental form, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt of aluminum.

[0091] In some embodiments, the M source is selected from at least one of aluminum sulfate, sodium aluminate, aluminum nitrate, aluminum chloride, boehmite, alumina, aluminum hydroxide, silica-alumina zeolite molecular sieve, aluminum carbonate, elemental aluminum, aluminum isopropoxide, and aluminum acetate.

[0092] In some embodiments, the fluorine source is selected from at least one of hydrofluoric acid, ammonium fluoride, sodium fluoride, and potassium fluoride, preferably at least one of hydrofluoric acid and ammonium fluoride.

[0093] In some embodiments, the structure directing agent is selected from those containing 1,1,3,5-tetraalkylpiperidine onium ions; preferably, the structure directing agent is 1,1,3,5-tetramethylpiperidine hydroxide.

[0094] The crystallization reaction described in this invention can be carried out under dynamic or static conditions. In this invention, the results of static and dynamic crystallization are essentially the same; therefore, the embodiments of this invention do not specifically describe static or dynamic conditions.

[0095] In some embodiments, the temperature of the crystallization reaction is 100-200°C, for example 100°C, 120°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C or any value between them.

[0096] In some embodiments, the temperature of the crystallization reaction is 110-190°C, more preferably 155-175°C.

[0097] In some embodiments, the crystallization reaction takes 72-600 hours, for example, 80 hours, 100 hours, 140 hours, 180 hours, 220 hours, 240 hours, 280 hours, 320 hours, 360 hours, or any value between them. Preferably, it takes 96-480 hours, more preferably 120-360 hours.

[0098] After the crystallization step described in this invention is completed, the molecular sieve can be separated from the obtained reaction mixture by any conventionally known separation method. Examples of such separation methods include filtration or centrifugation of the obtained reaction mixture. Filtration and centrifugation can be performed in any manner conventionally known in the art. Specifically, for example, filtration can be performed by simply vacuum filtering the obtained reaction mixture. Washing and drying in this invention can be performed in any manner conventionally known in the art. Specifically, for example, washing can be performed using deionized water. 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 performed under normal pressure or under reduced pressure. The present invention involves calcining the molecular sieve to remove the structure-directing agent and any present moisture. 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. Furthermore, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0099] Thirdly, the present invention provides a molecular sieve composition comprising the SCM-47 molecular sieve described in the first aspect of the present invention, and a binder.

[0100] The SCM-47 molecular sieve described in this invention can be used in combination with other materials to obtain molecular sieve compositions. Examples of these other materials include active materials such as synthetic and natural zeolites, and inactive materials (generally referred to as binders) such as clay, kaolin, silica gel, alumina, silicon dioxide, and magnesium oxide. These other materials can be used individually or in combination in any proportion. The amounts of these other materials used can be directly referenced from conventional amounts used in the art and are not particularly limited.

[0101] Fourthly, the present invention provides the application of the SCM-47 molecular sieve described in the first aspect or the molecular sieve composition described in the third aspect of the present invention in catalytic reactions, adsorption or ion exchange.

[0102] The SCM-47 molecular sieve or a molecular sieve composition containing the SCM-47 molecular sieve described in this invention can be used as an adsorbent, for example, to separate at least one component from a mixture of multiple components in the gas or liquid phase. Accordingly, the at least one component can be partially or substantially completely separated from the mixture of various components, specifically by contacting the mixture with the SCM-47 molecular sieve or a molecular sieve composition containing the SCM-47 molecular sieve to selectively adsorb the component. Furthermore, the SCM-47 molecular sieve or a molecular sieve composition containing the SCM-47 molecular sieve described in this invention can also be used as a catalyst, particularly in organic compound conversion reactions.

[0103] The present invention has the following beneficial effects:

[0104] 1. This invention provides a novel SCM-47 molecular sieve.

[0105] 2. The SCM-47 molecular sieve of the present invention has a thin sheet structure, with a high specific surface area and a large micropore volume.

[0106] 3. The SCM-47 molecular sieve framework of the present invention contains Si and optional other elements, which can present different catalytic active centers to meet the needs of different reactions. Attached Figure Description

[0107] The accompanying drawings are provided to further understand this application and form part of the specification. They are used together with the following detailed description to explain this application, but do not constitute a limitation thereof.

[0108] Figure 1 This is a topological diagram of SCM-47 molecular sieve in one embodiment of the present invention;

[0109] Figure 2 This is a schematic diagram of the contact between the molecular sieve precursor SCM-47P and the treatment liquid in one embodiment of the present invention;

[0110] Figure 3 The X-ray diffraction (XRD) pattern of the SCM-47 molecular sieve prepared in Example 1 is shown.

[0111] Figure 4 This is a scanning electron microscope (SEM) image of the SCM-47 molecular sieve prepared in Example 1;

[0112] Figure 5 The nitrogen adsorption-desorption isotherm of the SCM-47 molecular sieve prepared in Example 1;

[0113] Figure 6 The X-ray diffraction (XRD) pattern of the SCM-47 molecular sieve prepared in Example 5 is shown.

[0114] Figure 7 This is a scanning electron microscope (SEM) image of the SCM-47 molecular sieve prepared in Example 5;

[0115] Figure 8 This is the nitrogen adsorption-desorption isotherm of the SCM-47 molecular sieve prepared in Example 5. Detailed Implementation

[0116] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way.

[0117] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0118] In this paper, specific surface area refers to the total area per unit mass of a sample, including internal and external surface areas. Non-porous samples only have external surface area, such as silicate cement and some clay mineral powders; porous and multi-porous samples have both external and internal surface areas, such as asbestos fibers, diatomaceous earth, and molecular sieves. In porous and multi-porous samples, the surface area of ​​pores with a diameter less than 2 nm is the internal surface area, and the surface area after deducting the internal surface area is called the external surface area. The external surface area per unit mass of a sample is the external specific surface area.

[0119] In this paper, pore volume refers to the volume of pores per unit mass of porous material. Total pore volume refers to the volume of all pores per unit mass of molecular sieve (generally only pores with a channel diameter of less than 50 nm are included). Micropore volume refers to the volume of all micropores per unit mass of molecular sieve (generally referring to pores with a channel diameter of less than 2 nm).

[0120] In this paper, the specific surface area, pore volume, and micropore volume of the molecular sieve were determined by nitrogen physical adsorption under test conditions of 77 K. The specific surface area was calculated using the BET (Brunauer-Emmett-Teller) method, with points ranging from a relative pressure P / P0 of 0.01 to 0.1. The total pore volume was calculated using the adsorption amount corresponding to a relative pressure P / P0 of 0.99. The micropore volume was calculated using the t-plot method. All of the above test methods are well known to those skilled in the art.

[0121] In this paper, the structure of the molecular sieve was determined by X-ray diffraction (XRD), which was measured using an X-ray powder diffractometer with a Cu-Kα source and a Kα1 wavelength λ = 1.5405980 angstroms. Nickel filter.

[0122] In this invention, an X'Pert PRO X-ray powder diffractometer from Panaco GmbH, Netherlands, is used, with an operating voltage of 40 kV, a current of 40 mA, and a scanning range of 5–40°.

[0123] In this invention, the scanning electron microscope (SEM) images were obtained using a HITACHI S4800 field emission scanning electron microscope from Japan, under the following test conditions: voltage 3kV, current 50mA.

[0124] In this invention, the silicon and germanium content of the molecular sieve was obtained by ICP testing. The instrument model was Agilent 725-ESICP-AES. The molar ratio of the elements was determined by dissolving the analytical sample in hydrofluoric acid.

[0125] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this specification are based on weight, unless being based on weight would not be in accordance with the common understanding of those skilled in the art.

[0126] Unless otherwise specified, all reagents used in the following embodiments of the present invention are commercially available.

[0127] Unless otherwise specified, "Si / Ge" in this invention refers to the molar ratio of SiO2 to GeO2.

[0128] Example 1

[0129] Dissolve 1.2 g of germanium source (germanium oxide) and 0.408 g of M source (aluminum isopropoxide) in 15.82 g of 1,1,3,5-tetramethylpiperidine hydroxide (1,1,3,5-TMPOH) aqueous solution (20 wt%). Slowly add 5.942 g of silicon source (tetraethyl orthosilicate (TEOS)). Stir at room temperature until hydrolysis is complete. Then, leave the container open and stir overnight to evaporate ethanol, isopropanol, and some water. Add 1 g of hydrofluoric acid (40 wt%), stir until homogeneous, and adjust the water volume until the reaction mixture reaches the following molar composition:

[0130] 0.5(1,1,3,5-TMPOH):0.714SiO2:0.286GeO2:0.025Al2O3:0.5HF:19H2O

[0131] The above mixture was placed in a crystallization vessel lined with polytetrafluoroethylene and crystallized in an oven at 175°C for 336 hours. The solid after reaction was filtered, washed with distilled water, dried at 100°C, and calcined in a muffle furnace at 550°C for 5 hours to obtain the precursor SCM-47P.

[0132] Take 0.3g of precursor SCM-47P, add 15g of 12M HCl solution, stir at 25℃ for 15 minutes, filter the solid, wash with distilled water, dry at 100℃, and calcine in a muffle furnace at 550℃ for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern is shown below. Figure 3 As shown, the spectral data are presented in Table 1. The SEM images are shown below. Figure 4 As shown, by Figure 4 It can be seen that SCM-47 molecular sieve is a plate-like crystal with a layer thickness of approximately 40 nm. The nitrogen adsorption-desorption isotherm is shown below. Figure 5 As shown, by Figure 5 It can be seen that SCM-47 molecular sieve has a type I isotherm and a specific surface area of ​​246 m². 2 / g, micropore volume is 0.089cm³ 3 / g.

[0133] Table 1

[0134]

[0135]

[0136] Example 2

[0137] Take 0.3g of the precursor SCM-47P from Example 1, add 30g of 12M HCl solution, stir at 15°C for 4 hours, filter the solid, wash with distilled water, dry at 100°C, and calcine in a muffle furnace at 550°C for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern data are shown in Table 2.

[0138] Table 2

[0139]

[0140] Example 3

[0141] Take 0.3g of the precursor SCM-47P from Example 1, add 15g of 10M HNO3 solution, stir at 20°C for 20 minutes, filter the solid, wash with distilled water, dry at 100°C, and calcine in a muffle furnace at 550°C for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern is similar to... Figure 3 resemblance.

[0142] Example 4

[0143] Take 0.3g of the precursor SCM-47P from Example 1, place it on a polytetrafluoroethylene porous membrane, put it in a polytetrafluoroethylene liner, and add 30g of 12M HCl solution to the bottom of the reactor to allow the HCl vapor to contact the precursor SCM-47P. After reacting at 32°C for 12 hours, the solid is filtered, washed with distilled water, dried at 100°C, and calcined in a muffle furnace at 550°C for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern is consistent with... Figure 3 resemblance.

[0144] Example 5

[0145] Dissolve 1.046 g of germanium oxide and 0.326 g of aluminum isopropoxide in 15.82 g of an aqueous solution of 1,1,3,5-tetramethylpiperidine hydroxide (1,1,3,5-TMPOH) (20 wt%). Slowly add 6.24 g of tetraethyl orthosilicate (TEOS). Stir at room temperature until hydrolysis is complete. Then, leave the container open and stir overnight to evaporate ethanol, isopropanol, and some water. Add 1 g of hydrofluoric acid (40 wt%), stir until homogeneous, and adjust the water volume until the reaction mixture reaches the following molar composition:

[0146] 0.5(1,1,3,5-TMPOH):0.75SiO2:0.25GeO2:0.02Al2O3:0.5HF:17H2O

[0147] The above mixture was placed in a crystallization vessel lined with polytetrafluoroethylene and crystallized in an oven at 175°C for 336 hours. The solid after reaction was filtered, washed with distilled water, dried at 100°C, and calcined in a muffle furnace at 550°C for 5 hours to obtain the precursor SCM-47P.

[0148] Take 0.3g of precursor SCM-47P, add 9g of 12M HCl solution, stir at 25℃ for 30 minutes, filter the solid, wash with distilled water, dry at 100℃, and calcine in a muffle furnace at 550℃ for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern is shown below. Figure 6 As shown, the spectral data are presented in Table 3. The SEM images are shown below. Figure 7 As shown, by Figure 7 It can be seen that SCM-47 molecular sieve is a plate-like crystal with a layer thickness of approximately 60 nm. The nitrogen adsorption-desorption isotherm is shown below. Figure 8 As shown, by Figure 8 It can be seen that SCM-47 molecular sieve has a type I isotherm and a specific surface area of ​​267 m². 2 / g, micropore volume is 0.097cm³ 3 / g.

[0149] Table 3

[0150]

[0151] Example 6

[0152] Take 0.3g of the precursor SCM-47P from Example 5, place it on a polytetrafluoroethylene porous membrane, put it in a polytetrafluoroethylene liner, and add 12g of 12M HCl solution to the bottom of the reactor to allow the HCl vapor to contact the precursor SCM-47P. After reacting at 30°C for 8 hours, the solid was filtered, washed with distilled water, dried at 100°C, and calcined in a muffle furnace at 550°C for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern was similar to that of Example 5.

[0153] Example 7

[0154] Dissolve 1.394 g of germanium oxide and 0.544 g of aluminum isopropoxide in 15.82 g of an aqueous solution of 1,1,3,5-tetramethylpiperidine hydroxide (1,1,3,5-TMPOH) (20 wt%). Slowly add 5.549 g of tetraethyl orthosilicate (TEOS). Stir at room temperature until hydrolysis is complete. Then, leave the container open and stir overnight to evaporate ethanol, isopropanol, and some water. Add 1 g of hydrofluoric acid (40 wt%), stir until homogeneous, and adjust the water volume until the reaction mixture reaches the following molar composition:

[0155] 0.5(1,1,3,5-TMPOH):0.667SiO2:0.333GeO2:0.033Al2O3:0.5HF:20H2O

[0156] The above mixture was placed in a crystallization vessel lined with polytetrafluoroethylene and crystallized in an oven at 175°C for 336 hours. The solid after reaction was filtered, washed with distilled water, dried at 100°C, and calcined in a muffle furnace at 550°C for 5 hours to obtain the precursor SCM-47P.

[0157] Take 0.3g of precursor SCM-47P, add 30g of 12M HCl solution, stir at 22℃ for 10 minutes, filter the solid, wash with distilled water, dry at 100℃, and calcine in a muffle furnace at 550℃ for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern data are shown in Table 4.

[0158] Table 4

[0159]

[0160] Example 8

[0161] Take 0.3g of the precursor SCM-47P from Example 7, add 15g of 14M HNO3 solution, stir at 20°C for 40 minutes, filter the solid, wash with distilled water, dry at 100°C, and calcine in a muffle furnace at 550°C for 5 hours to obtain SCM-47 molecular sieve. The XRD pattern is similar to that of Example 7.

[0162] Example 9

[0163] Take 0.3g of the precursor SCM-47P from Example 1, add 10g of 3M Al(NO3)3 solution and 5g of 12M HCl solution, stir at 18°C ​​for 60 minutes, filter the solid, wash with distilled water, dry at 100°C, and calcine in a muffle furnace at 550°C for 5 hours to obtain high-silicon aluminum-containing SCM-47 molecular sieve with Si / Al = 185. The XRD spectrum data are shown in Table 5.

[0164] Table 5

[0165]

[0166] Example 10

[0167] Take 0.3g of the precursor SCM-47P from Example 1, add 5g of 1M (NH4)2TiF6 solution and 10g of 12M HCl solution, stir at 35°C for 90 minutes, filter the solid, wash with distilled water, dry at 100°C, and calcine in a muffle furnace at 550°C for 5 hours to obtain a high-silicon titanium-containing SCM-47 molecular sieve with Si / Ti = 145. The XRD pattern is similar to... Figure 3 resemblance.

[0168] The parameters in the above embodiments are shown in Table 6.

[0169] Table 6

[0170]

[0171]

[0172] In Table 6, the Si / Ge ratio of the molecular sieve precursor feed refers to the molar ratio of SiO2 and GeO2 in the silicon source and germanium source; the Si / Ge ratio of the molecular sieve precursor product refers to the molar ratio of SiO2 and GeO2 in the molecular sieve precursor SCM-47P; and the Si / Ge ratio of the molecular sieve refers to the molar ratio of SiO2 and GeO2 in the SCM-47 molecular sieve prepared in Examples 1-10.

[0173] As shown in Table 6, due to the degermanium removal process of the molecular sieve precursor after treatment with the treatment solution, the final silicon-germanium ratio (molar ratio of SiO2 and GeO2) in the SCM-47 molecular sieve is ≥50. At this point, the germanium content in the SCM-47 molecular sieve is significantly lower than that in the molecular sieve precursor.

[0174] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various 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. An SCM-47 molecular sieve, the X-ray diffraction pattern of which includes one or more diffraction peaks with 2θ of 7.08°±0.30°, 8.68°±0.30°, 13.08°±0.30°, and 15.78°±0.30°, preferably the diffraction peak with 2θ of 8.68°±0.30° is the strongest peak.

2. The SCM-47 molecular sieve according to claim 1, characterized in that, The X-ray diffraction pattern of the SCM-47 molecular sieve also includes one or more diffraction peaks with 2θ values ​​of 19.90°±0.30°, 21.87°±0.30°, 23.42°±0.30°, 24.96°±0.30°, 26.46°±0.30°, and 28.00°±0.30°. Preferably, the X-ray diffraction pattern of the SCM-47 molecular sieve includes the X-ray diffraction peaks shown in Table A: Table A ； Preferably, the X-ray diffraction pattern of the SCM-47 molecular sieve also includes the X-ray diffraction peaks shown in Table B: Table B ； Preferably, the X-ray diffraction pattern of the SCM-47 molecular sieve includes the X-ray diffraction peaks shown in Table C: Table C Preferably, the X-ray diffraction pattern of the SCM-47 molecular sieve also includes the X-ray diffraction peaks shown in Table D: Table D 。 3. The SCM-47 molecular sieve according to claim 1 or 2, characterized in that, The SCM-47 molecular sieve comprises SiO2 and GeO2, wherein the molar ratio of SiO2 to GeO2 is 50 or more, preferably 65 or more; Preferably, the SCM-47 molecular sieve further includes MO. m / 2 Where M is a framework element other than silicon, m is the valence of element M, and m = 1 to 7. (SiO2 and MO) m / 2 The molar ratio is 20 or higher, preferably SiO2 and MO. m / 2 The molar ratio is 50-200; Preferably, the framework element M of the SCM-47 molecular sieve, excluding silicon, is selected from at least one of Group IIIA, Group IVA, Group IVB, Group IIB, Group VIB, Group VIIB, Group IA, Group IIA, Group VIII, Group VA, or Group VB elements, and more preferably from at least one of aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, vanadium, cobalt, nickel, arsenic, or antimony; and / or The SCM-47 molecular sieve has a plate-like crystal morphology with a plate thickness of 20–500 nm; and / or, The specific surface area of ​​the SCM-47 molecular sieve is greater than 150 m². 2 / g, and / or, the micropore volume of the SCM-47 molecular sieve is greater than 0.07cm³. 3 / g.

4. A method for preparing SCM-47 molecular sieve according to any one of claims 1-3, comprising the following steps: The molecular sieve precursor is brought into contact with the treatment liquid and reacted. Preferably, the Si / Ge ratio in the molecular sieve precursor is ≤5.5, the reaction temperature is 5℃-40℃, and the reaction time is 5min-15h. Preferably, the preparation method of SCM-47 molecular sieve further includes: The reaction is followed by post-processing, which includes solid-liquid separation, washing, drying, and calcination. Preferably, the calcination temperature is 300℃-800℃, more preferably 400℃-650℃; and / or The roasting time is 1 hour to 10 hours, preferably 3 hours to 6 hours.

5. The preparation method according to claim 4, characterized in that, The mass ratio of the treatment solution to the molecular sieve precursor is 20-300; preferably 30-100; and / or The treatment solution is selected from at least one of acid solution, alkaline solution or M' source aqueous solution; Preferably, the concentration of the acid solution is 0.01-20M, more preferably 0.01-14M; and / or The acid solution is selected from at least one of HCl aqueous solution, HCl alcoholic solution, H2SO4 aqueous solution, HNO3 aqueous solution, acetic acid solution, and ammonia aqueous solution, preferably HCl aqueous solution; and / or The concentration of the alkaline solution is 0.1-30 wt%, preferably 0.5-25 wt%; and / or The alkaline solution is selected from ammonia solution; and / or The M' source in the aqueous solution is selected from at least one water-soluble compound of Group IIIA, Group IVA, Group IVB, Group IIB, Group VIB, Group VIIB, Group IA, Group IIA, Group VIII, Group VA, or VB elements; preferably selected from at least one water-soluble compound of aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, cobalt, nickel, arsenic, or antimony. Preferably, the water-soluble compound is at least one of chloride, fluoride, sulfate, nitrate or acetate; Preferably, the source M' is selected from water-soluble aluminum compounds, water-soluble titanium compounds, and water-soluble iron compounds; Preferably, the water-soluble aluminum compound is selected from at least one of aluminum chloride, aluminum sulfate, aluminum nitrate, and aluminum acetate; and / or The water-soluble titanium compound is selected from at least one of titanium tetrachloride, titanium sulfate, and ammonium hexafluorotitanate; and / or The water-soluble iron compound is selected from at least one of ferric chloride, ferric sulfate, and ferric nitrate; More preferably, the source of M' is selected from aluminum nitrate and / or ammonium hexafluorotitanate.

6. The preparation method according to claim 4 or 5, characterized in that, The method for preparing the molecular sieve precursor includes: A mixture including silicon source, germanium source, M source, fluorine source, structure directing agent and water is subjected to a crystallization reaction; Preferably, the silicon source is SiO2, the germanium source is GeO2, and the M source is an oxide MO. m / 2 The fluorine source is calculated as F. In the mixture, the molar ratio of SiO2 to GeO2 is (2-3.5):1; and / or In the mixture, the sum of the molar numbers of SiO2 and GeO2 and the molar number of MO m / 2 The ratio of the number of moles is (15-30):1; and / or In the mixture, the molar ratio of the sum of the molar numbers of SiO2 and GeO2 to F is 1:(0.1-1); and / or In the mixture, the molar ratio of the sum of the molar numbers of SiO2 and GeO2 to the molar ratio of the structure-directing agent is 1:(0.1-1); and / or In the mixture, the molar ratio of the sum of the moles of SiO2 and GeO2 to water is 1:(12.5-25); Preferably, the mixture contains a structure-directing agent, SiO2, GeO2, and MO. m / 2 The molar ratio of F to water is 0.5:(0.667-0.778):(0.222-0.333):(0.0333-0.0667):0.5:(12.5-25).

7. The preparation method according to claim 6, characterized in that, The silicon source is selected from at least one of water glass, silica sol, solid silica gel, fumed silica, amorphous silica, diatomaceous earth, zeolite molecular sieve, and tetraalkoxysilane; and / or The germanium source is selected from at least one of germanium oxide, germanium nitrate, and tetraalkoxy germanium; and / or The skeletal element M source, excluding silicon, is selected from at least one of the following group elements: Group IIIA, Group IVA, Group IVB, Group IIB, Group VIB, Group VIIB, Group IA, Group IIA, Group VIII, Group VA, or Group VB; its elemental form, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt. Preferably, it is selected from at least one of the following group elements: aluminum, boron, gallium, indium, germanium, tin, titanium, zirconium, hafnium, zinc, chromium, manganese, lithium, beryllium, magnesium, iron, phosphorus, vanadium, cobalt, nickel, arsenic, or antimony; its elemental form, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt. Preferably, the M source is selected from at least one of the following: elemental aluminum, chloride, oxide, hydroxide, nitrate, sulfate, carbonate, acetate, isopropoxide, or metaacid salt; Preferably, the M source is selected from at least one of aluminum sulfate, sodium aluminate, aluminum nitrate, aluminum chloride, boehmite, alumina, aluminum hydroxide, silica-alumina zeolite molecular sieve, aluminum carbonate, elemental aluminum, aluminum isopropoxide, and aluminum acetate; and / or The fluorine source is selected from at least one of hydrofluoric acid, ammonium fluoride, sodium fluoride, and potassium fluoride; and / or The structure directing agent is selected from those containing 1,1,3,5-tetraalkylpiperidine onium ions; preferably, the structure directing agent is 1,1,3,5-tetramethylpiperidine hydroxide.

8. The preparation method according to any one of claims 4-7, characterized in that, The crystallization reaction is carried out at a temperature of 100-200℃, preferably 155-175℃; and / or The crystallization reaction takes 72-600 hours, preferably 120-360 hours; and / or The method further includes post-processing after the crystallization reaction, the post-processing including filtration, washing, drying and optional calcination steps.

9. A molecular sieve composition comprising the SCM-47 molecular sieve according to any one of claims 1-3, and a binder; Preferably, the binder is selected from at least one of clay, kaolin, silica gel, alumina, silicon dioxide, and magnesium oxide.

10. The use of the SCM-47 molecular sieve according to any one of claims 1-3 or the molecular sieve composition according to claim 9 in catalytic reactions, adsorption or ion exchange.

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