CN115991490A

CN115991490A - Eutectic molecular sieve and preparation method thereof

Info

Publication number: CN115991490A
Application number: CN202111224533.4A
Authority: CN
Inventors: 赵胜利; 乔健; 袁志庆; 王振东; 付文华; 陶伟川
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2021-10-20
Filing date: 2021-10-20
Publication date: 2023-04-21

Abstract

The invention discloses a eutectic molecular sieve and a preparation method thereof. The eutectic molecular sieve is a eutectic molecular sieve of an SCM-38 molecular sieve and a CHA molecular sieve, and the chemical composition comprises the following components in mole ratio: siO (SiO) ₂ ：Al ₂ O ₃ ：P ₂ O ₅ = (0.08-0.80): (0.88-1.30): 1, the XRD pattern of the eutectic molecular sieve comprises X-ray diffraction peaks at 7.20± 0.1,9.49 ±0.1, 10.81±0.1, 11.60±0.1, 15.98±0.1, 20.56±0.1, 30.55±0.1, 31.32 ±0.1. The eutectic molecular sieve provided by the invention can be applied to adsorbents or catalysts.

Description

Eutectic molecular sieve and preparation method thereof

Technical Field

The invention belongs to the field of molecular sieves, and particularly relates to a novel eutectic molecular sieve and a preparation method thereof.

Background

Molecular sieves are porous crystalline materials and are widely applied to the chemical fields of oil refining, catalysis and the like. Different pore channel structures show different macroscopic properties such as adsorption, catalysis and the like, and molecular sieves with different structures have also been synthesized. The known structure molecular sieves found today are up to 250 or more (including locally disordered). Because the molecular sieve has uniform and regular pore channels, the pore channel size and the small organic molecules belong to the same order of magnitude, and molecules entering the molecular sieve can be 'sieved' according to the space size of the molecules in the chemical reaction, so that certain selective adsorption and catalytic shape-selective effects are obtained. The framework of molecular sieves is typically composed of coordination tetrahedra (TO ₄ ) Through a common vertex (typically an oxygen atom). For conventional zeolite molecular sieves, the tetrahedra in the framework are predominantly silica tetrahedra and alumina tetrahedra, which may also be replaced with other tetrahedra, respectively, to form a number of molecular sieves of various framework structures or framework compositions.

In 1971, flanigen et al (Molecular Sieve Zeolites-I, ACS, washingtom D.C) reported the synthesis of aluminum phosphate molecular sieves, which can be understood as the substitution of the siloxane tetrahedra in zeolite molecular sieves with phosphorus-oxygen tetrahedra to form molecular sieves. The framework of the molecular sieve passes through AlO ₄ ^- And PO (PO) ₄ ⁺ The common oxygen atoms are connected to form the whole molecular sieve framework which presents electric neutrality. Similar to zeolite fractionThe molecular sieve, aluminum oxide tetrahedra or phosphorus oxide tetrahedra in the aluminum phosphate molecular sieve can also be replaced by other tetrahedra, the most common of which are silicon oxygen tetrahedra and zinc oxygen tetrahedra, and the introduction of these tetrahedra imparts new characteristics to the aluminum phosphate molecular sieve. Compared with zeolite molecular sieve, the synthetic research of aluminium phosphate molecular sieve is relatively late. Under hydrothermal synthesis conditions, mixing oxides of aluminum, silicon and phosphorus to obtain a silicon-phosphorus-aluminum molecular sieve with the same crystal structure as that of analcime (analcime), chabazite (chabazite), phillipsite-alternantite (philipsite-hamotome), L-type molecular sieve, A-type molecular sieve, B-type molecular sieve and the like, wherein the content of phosphorus is 5-25% (in terms of P ₂ O ₅ Based on the weight of the zeolite), no molecular sieve other than the known zeolite molecular sieve structure has been found. U.S. patent No. 4310440 in 1982 hydrothermally synthesized a series of aluminum phosphate molecular sieves using organic amines or quaternary ammonium compounds as templates, which included: alPO (AlPO) ₄ -5，AlPO ₄ -8，AlPO ₄ -9，AlPO ₄ -11，AlPO ₄ -12，AlPO ₄ -14，AlPO ₄ -16，AlPO ₄ -17，AlPO ₄ -18，AlPO ₄ -20，AlPO ₄ -21，AlPO ₄ -22，AlPO ₄ -23，AlPO ₄ -25，AlPO ₄ -26，AlPO ₄ -28，AlPO ₄ -31, etc. With the continuous deep understanding of the structure, performance, synthesis method, condition and other factors of molecular sieve and the continuous progress of synthesis technology, molecular sieve with new structure is synthesized continuously. For the synthesis of the phosphorus-aluminum molecular sieve, the type of the organic template agent is one of the key factors for determining the structure of the organic template agent. So far, organic amine is still the most widely used template agent in the synthesis of phosphorus-aluminum molecular sieves. Compared with the silicon aluminum zeolite molecular sieve, the industrial application of the phosphorus aluminum molecular sieve is not seen, and only few molecular sieves currently obtain 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) report that SAPO molecular sieves have been used as part of a coupling catalyst in a synthesis gas to olefins reaction to achieve good catalytic results. Su et al (Su, J., zhou, H., liu, S.et al Syngas to light olefins conversion wit)h high olefin/paraffin ratio using ZnCrOx/AlPO-18bifunctional catalysts.Nat Commun 10,1297 (2019) reveals that a bifunctional catalyst prepared from an aluminophosphate type molecular sieve with a metal oxide has excellent performance in the direct conversion of synthesis gas to olefins of high olefin to alkane ratio, and from the above, it can be seen that the aluminophosphate type molecular sieve has great industrial application potential.

Because different pore channel structures and element compositions determine the special physical and chemical properties and catalytic properties of the molecular sieve, and different molecular sieves respectively maintain own characteristics in adsorption or reaction, the development of the eutectic molecular sieve can make up for the defects of the self properties of a single molecular sieve, and therefore, the research and development of the eutectic molecular sieve are particularly important.

Disclosure of Invention

The invention aims to solve the technical problem of providing a novel eutectic molecular sieve which is not involved in the prior art and a preparation method thereof.

The invention provides a eutectic molecular sieve, which is a eutectic molecular sieve of an SCM-38 molecular sieve and a CHA molecular sieve, and comprises the following chemical components in a molar ratio: siO (SiO) ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ The XRD pattern of the eutectic molecular sieve comprises X-ray diffraction peaks at 7.20+/-0.1,9.49 +/-0.1, 10.81+/-0.1, 11.60+/-0.1, 15.98+/-0.1, 20.56+/-0.1, 30.55+/-0.1 and 31.32 +/-0.1 of 2 theta.

Further, in the XRD spectrum of the eutectic molecular sieve, an X-ray diffraction peak, namely a characteristic peak of the SCM-38 molecular sieve appears at the positions of 7.20+/-0.1, 10.81+/-0.1 and 11.60+/-0.1 of 2 theta, wherein the position of the 2 theta in the characteristic peak of the SCM-38 molecular sieve is the strongest peak. Preferably, the XRD pattern of the co-crystal molecular sieve comprises X-ray diffraction peaks as shown in the following table, wherein the intensity of the strongest peak of the characteristic peaks of the SCM-38 molecular sieve is calculated as 100%:

2θ(°)	relative strength, [ (I/I) ₀ )×100]
		7.20±0.1	100
10.81±0.1	5-80
		11.60±0.1	5-80

。

Further, in the XRD pattern of the eutectic molecular sieve, the characteristic peaks of the SCM-38 molecular sieve also comprise X-ray diffraction peaks at the positions of 14.32+/-0.1, 21.39 +/-0.1, 21.83+/-0.1, 27.31+/-0.1 and 28.72+/-0.1 of 2 theta, namely the characteristic peaks further comprise the SCM-38 molecular sieve. Preferably, the XRD pattern of the co-crystal molecular sieve comprises X-ray diffraction peaks as shown in the following table, calculated as 100% intensity of the strongest of the characteristic peaks of the SCM-38 molecular sieve:

2θ(°)	relative strength, [ (I/I) ₀ )×100]
		14.32±0.1	5-50
21.39±0.1	5-50
		21.83±0.1	5-50
27.31±0.1	5-50
		28.72±0.1	5-50

。

Further, in the XRD spectrum of the eutectic molecular sieve, X-ray diffraction peaks, namely characteristic peaks of the CHA molecular sieve, appear at the positions of 9.49+/-0.1, 15.98+/-0.1, 20.56+/-0.1, 30.55+/-0.1 and 31.32 +/-0.1, and the characteristic peaks of the CHA molecular sieve are the strongest peaks at the positions of 9.49+/-0.1 or 20.56+/-0.1.

Further, the XRD pattern of the eutectic molecular sieve comprises X-ray diffraction peaks (i.e., diffraction peaks of the CHA molecular sieve) shown in the following table, calculated as 100% of the intensity of the strongest peak among the characteristic peaks of the CHA molecular sieve:

2θ(°)	relative strength, [ (I/I) ₀ )×100]
		9.49±0.1	5-100
15.98±0.1	5-80
		20.56±0.1	5-100
30.55±0.1	5-80
		31.32±0.1	5-80

。

Further, in the XRD pattern of the eutectic molecular sieve, characteristic peaks of the CHA molecular sieve further include X-ray diffraction peaks occurring at 2θ of 12.82±0.1, 14.08±0.1, 18.01±0.1, 25.25±0.1, 25.84±0.1, i.e., characteristic peaks further included in the CHA molecular sieve.

Further, preferably, the XRD pattern of the co-crystal molecular sieve further comprises X-ray diffraction peaks (i.e., characteristic peaks further comprised by the CHA molecular sieve) as shown in the following table, calculated as 100% of the intensity of the strongest peak of the characteristic peaks of the CHA molecular sieve:

2θ(°)	relative strength, [ (I/I) ₀ )×100]
		12.82±0.1	1-50
14.08±0.1	1-50
		18.01±0.1	1-50
25.25±0.1	1-50
		25.84±0.1	1-50

。

Further, the chemical composition of the eutectic molecular sieve comprises, in terms of mole ratio: siO (SiO) ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ = (0.08-0.80): (0.88-1.30): 1, preferably SiO ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ ＝(0.11-0.80)∶(0.88-1.30)∶1。

Further, the eutectic molecular sieve is a eutectic molecular sieve of a CHA molecular sieve and a SCM-38 molecular sieve, wherein the content of the CHA molecular sieve and the SCM-38 molecular sieve is not particularly limited, further, in the eutectic molecular sieve, the CHA molecular sieve accounts for 1% -99% of the mass of the eutectic molecular sieve, further 10% -90%, and the SCM-38 molecular sieve accounts for 1% -99% of the mass of the eutectic molecular sieve, further 10% -90%.

Further, the eutectic molecular sieve is a CHA molecular sieve, preferably a SAPO-34 molecular sieve.

The second aspect of the present invention provides a method for preparing the eutectic molecular sieve, comprising:

a) The aluminophosphate precursor, a silicon source and an organic base R ₁ R is organic matter ₂ Mixing a fluorine source, water and optionally an aluminum source A to obtain a synthetic mother liquor;

b) Crystallizing the synthesis mother liquor in the step a) to obtain a eutectic molecular sieve;

wherein the organic base R ₁ One or more of tetramethyl ammonium hydroxide, tetraethyl ammonium hydroxide, tetrapropyl ammonium hydroxide and the like; the organic matter R ₂ 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, the chemical structural formula of which is shown as follows:

the aluminophosphate precursor has the formula of Al ₂ O ₃ ：xP ₂ O ₅ "the chemical composition is shown, wherein x is more than or equal to 0.8 and less than or equal to 2; the XRD pattern of the aluminophosphate precursor mainly comprises X-ray diffraction peaks shown in the following table:

2θ(°)	relative strength, [ (I/I) ₀ )×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

。

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

2θ(°)	relative strength, [ (I/I) ₀ )×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

。

Further, in the synthetic mother solution, the molar ratio of each material is as follows: silicon source is SiO ₂ Meter, aluminum source A is Al ₂ O ₃ Metering the aluminum phosphate precursor by Al ₂ O ₃ 、P ₂ O ₅ Meter, organic base R ₁ R is organic matter ₂ Fluorine source in HF and water in H ₂ O meter, (0.08-0.80) SiO ₂ ：(0.88-1.3)Al ₂ O ₃ ：1P ₂ O ₅ ：(0.3-0.8)R ₁ ：(1-2)R ₂ ：(0.5-1.8)HF：(50-130)H ₂ O. Wherein the amount of the aluminum source A is based on the Al in the aluminophosphate precursor ₂ O ₃ Is determined by the amount of Al provided by the aluminophosphate precursor ₂ O ₃ When the amount of the aluminum source A meets the proportioning requirement, the aluminum source A is not added, and when the aluminum source A is provided by the aluminophosphate precursor ₂ O ₃ When the amount of the aluminum source A cannot meet the proportioning requirements, the aluminum source A is added to meet the proportioning requirements.

Further, in the synthetic mother solution, in the molar ratio of each material, siO ₂ ∶P ₂ O ₅ = (0.08-0.80) to 1, preferably (0.11-0.80) to 1.

Further, the aluminum source A is selected from one or more of pseudo-boehmite, aluminum isopropoxide, aluminum sol, aluminum oxide and the like.

Further, the silicon source is selected from one or more of silica sol, fumed silica and the like, preferably silica sol;

further, the fluorine source is selected from aqueous HF solutions.

Further, in step a), the order of addition of the materials is not particularly limited, and is preferably: mixing water, optional aluminum source A, silicon source and aluminophosphate precursor, and adding organic matter R successively ₂ An organic base R ₁ And mixing uniformly, and adding a fluorine source.

Further, in the step b), the crystallization conditions are as follows: the crystallization temperature is 160-210 ℃, the crystallization time is 8-100 hours, preferably 170-200 ℃, and the crystallization time is 20-84 hours.

Further, step b) after the crystallization step is completed, the eutectic molecular sieve product may be separated from the obtained mixture by any conventionally known separation means, such as separation, washing and drying. The separation, washing and drying may be carried out in any manner conventionally known in the art, wherein separation is, for example, centrifugation or filtration, suction filtration; the drying temperature is selected from 40-120deg.C, preferably 50-80deg.C; as the drying time, 8 to 48 hours, preferably 12 to 24 hours. The drying can be carried out under normal pressure or reduced pressure, and is usually carried out under normal pressure for saving energy.

In a third aspect the present invention provides a eutectic molecular sieve composition comprising a eutectic molecular sieve according to any one of the preceding aspects or a eutectic molecular sieve prepared according to a method of preparing a eutectic molecular sieve according to any one of the preceding aspects, and a binder.

According to a fourth aspect of the present invention there is provided the use of a co-crystal molecular sieve according to any of the preceding aspects, a co-crystal molecular sieve prepared according to a method of preparing a co-crystal molecular sieve according to any of the preceding aspects, or the use of a co-crystal molecular sieve composition according to any of the preceding aspects in an adsorbent or catalyst.

Further, the co-crystal molecular sieve or molecular sieve composition is used as an adsorbent, for example, to separate at least one component from a mixture of components in a gas phase or a liquid phase. Accordingly, the at least one component may be partially or substantially completely separated from the mixture of components, such as by contacting the mixture with the eutectic molecular sieve or the molecular sieve composition to selectively adsorb the component.

Further, the co-crystal molecular sieve or molecular sieve composition may be used in a catalyst for organic conversion.

The eutectic molecular sieve of the invention is a novel eutectic molecular sieve, in particular to a novel eutectic molecular sieve of a molecular sieve SCM-38 and a CHA molecular sieve (particularly a SAPO-34 molecular sieve), and the types and the synthesis methods of the eutectic molecular sieve are enriched.

Drawings

FIG. 1 is an XRD pattern of aluminophosphate precursor A obtained in example 1;

FIG. 2 is an XRD pattern of aluminophosphate precursor B obtained in example 2;

FIG. 3 is an XRD pattern of the eutectic molecular sieve obtained in example 3;

FIG. 4 is an XRD pattern of the eutectic molecular sieve obtained in example 10;

FIG. 5 is an XRD pattern of the SCM-38 molecular sieve obtained in comparative example 1;

FIG. 6 is an XRD pattern of the SAPO-34 molecular sieve obtained in comparative example 2.

Detailed Description

The following detailed description of the embodiments of the invention is provided, and the scope of the invention is not limited to these embodiments.

In the present invention, the structure of the molecular sieve is determined by X-ray diffraction (XRD) patterns determined by X' Pert PRO X-ray powder diffraction (XRD) of the Panac company of Netherlands, using a Cu-K alpha ray source, K alpha 1 wavelength

The nickel filter has an operating voltage of 40kV, a current of 40mA and a scanning range of 3-50 degrees.

In the present invention, siO in the molecular sieve ₂ 、Al ₂ O ₃ And P ₂ O ₅ The composition of (C) was measured by ICP method. The elemental ratios in the samples were analyzed using a Varianalytical 725-ES inductively coupled plasma emission spectrometer from Varianan, inc. of America.

The aluminophosphate precursor of the invention has the formula of Al ₂ O ₃ ：xP ₂ O ₅ "the schematic chemical composition is shown, wherein x is more than or equal to 0.8 and less than or equal to 2; the XRD pattern of the aluminophosphate precursor includes X-ray diffraction peaks as shown in the following table:

。

2θ(°)	relative strength, [ (I/I) ₀ )×100]
		14.25±0.1	5-50
21.01±0.1	10-20
		24.27±0.05	5-50
26.05±0.05	5-50
		27.82±0.05	5-50
28.15±0.02	5-50
		30.03±0.02	5-50

。

Further, the preparation method of the phosphoaluminate precursor comprises the following steps: the organic template agent R contains an aluminum source B, a phosphorus source _A And an organic template R _B Solvent S ₁ Solvent S ₂ And solvent S ₃ Crystallizing the mixture to obtain an aluminophosphate precursor;

wherein the organic template agent R _A One or more selected from quaternary ammonium salt or quaternary ammonium base; r is R _B One or more selected from imidazole or pyrrolidine derivatives; solvent S ₁ One or more solvents selected from amide solvents; solvent S ₂ One or more kinds of cyclic organic solvents; s is S ₃ One or more selected from water or lower alcohols.

Further, in the preparation method of the aluminophosphate precursor, the organic template agent R _A One or more selected from tetraethylammonium bromide, tetraethylammonium hydroxide, tetrapropylammonium bromide, tetrapropylammonium hydroxide, tetrabutylammonium bromide and tetrabutylammonium hydroxide; the organic template agent R _B One or more selected from imidazole, 2-methylimidazole, 4-methylimidazole, 1- (3-aminopropyl) imidazole, 2-ethyl-4-methylimidazole, pyrrolidine, 1- (3-pyrrolidine) pyrrolidine and N-ethyl-2-aminomethylpyrrolidine; the solvent S ₁ One or more selected from N, N-dimethylformamide, N-dimethylacetamide, N-diethylformamide and N, N-dibutylformamide; the solvent S ₂ One or more selected from 1, 4-dioxane, cyclohexane, cyclohexanone and the like; the solvent S ₃ One or more selected from methanol, ethanol, ethylene glycol, butanol, cyclohexanol and water.

Further, in the preparation method of the aluminophosphate precursor, the organic template agent R _A Preferably one or more of tetraethylammonium bromide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide; the organic template agent R _B Preferably one or more of 1- (3-aminopropyl) imidazole, 2-ethyl-4-methylimidazole and N-ethyl-2-aminomethylpyrrolidine; the solvent S ₁ Preferably one or more of N, N-dimethylacetamide and N, N-dibutylformamide; the solvent S ₂ Preferably one or both of 1, 4-dioxane and cyclohexanone; the solvent S ₃ Preferably one or both of ethanol and water, and more preferably deionized water.

Further, in the preparation method of the aluminophosphate precursor, the aluminum source B is prepared from Al in the mixture ₂ O ₃ Counting the phosphorus source by P ₂ O ₅ Meter, organic template agent R _A +R _B Solvent S ₁ +S ₂ +S ₃ The molar composition of (2) is as follows: p (P) ₂ O ₅ /Al ₂ O ₃ =0.75-2.2, preferably 1-2; template agent R _A +R _B /Al ₂ O ₃ =1-80, preferably 5-50; solvent S ₁ +S ₂ +S ₃ /Al ₂ O ₃ =5-500, preferably 35-120.

Further, in the preparation method of the aluminophosphate precursor, the organic template agent R _A With organic template agent R _B The molar ratio of (2) is 0.01-1:1, preferably 0.1-0.25:1.

Further, in the preparation method of the aluminophosphate precursor, the solvent S ₁ Solvent S ₂ With solvent S ₃ The molar ratio of (2) is 1:0.01-1:1-100, preferably 1:0.05-0.5:10-80.

Further, 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, hydroxide of aluminum, oxide of aluminum and mineral containing aluminum, preferably one or two of aluminate and meta-aluminate; the phosphorus source is at least one selected from phosphoric acid, monoammonium phosphate and monoammonium phosphate, preferably orthophosphoric acid.

Further, in the preparation method of the aluminophosphate precursor, stirring and sedimentation treatment are carried out before crystallization treatment. The stirring time is 0.5-5h, and the sedimentation treatment time is 1-12h.

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

Further, in the preparation method of the aluminophosphate precursor, the crystallization treatment is followed by conventional post-treatment, such as steps of filtering, washing and drying, to obtain the molecular sieve. The filtration, washing and drying may be performed in any manner conventionally known in the art, wherein separation such as centrifugation or filtration, suction filtration. The drying temperature is selected from 40-120deg.C, preferably 50-80deg.C; as the drying time, 8 to 48 hours, preferably 12 to 24 hours. The drying can be carried out under normal pressure or reduced pressure, and is usually carried out under normal pressure for saving energy.

The following examples are given to illustrate the technical aspects of the present invention in detail, but are not intended to limit the present patent.

[ example 1 ]

38g of aluminum nitrate [ Al (NO) ₃ ) ₃ ·9H ₂ O]Dissolving in 43mL deionized water, adding 25.2g phosphoric acid (purity: 85 wt.%), 151g tetrabutylammonium hydroxide (40 wt.% aqueous solution) and 145.6g 1- (3-aminopropyl) imidazole under stirring, stirring for 0.5h, precipitating for 12h to obtain solution A, adding 16mL N, N-dibutylformamide and 4.6mL cyclohexanone to the solution A, stirring for 3.5h, and heat treating at 90deg.C for 8h to obtain uniform crystallization mixture B, wherein Al is used as the material ₂ O ₃ Aluminum source, in P ₂ O ₅ The mole ratio of the phosphorus source, the total template agent and the total solvent is as follows: al (Al) ₂ O ₃ ∶P ₂ O ₅ Template R and solvent S=1:2.1:7:40, template R _A (tetrabutylammonium hydroxide) template agent R _B (1- (3-aminopropyl) imidazole) =0.2 (mass ratio of substances), solvent S ₁ (N, N-dibutylformamide) solvent S ₂ (Cyclohexanone) solvent S ₃ (water) =1:0.5:78.5 (molar ratio); and (3) placing the crystallization mixture B into a crystallization kettle with a tetrafluoroethylene lining, crystallizing for 5d at 140 ℃, filtering and washing a product, and drying at 80 ℃ for 24h to obtain an aluminophosphate precursor, namely A for later use. Wherein, in the phosphoaluminate precursor A, al ₂ O ₃ ∶P ₂ O ₅ =1:2. The XRD pattern of the aluminophosphate precursor A is shown in figure 1, i.e. it comprises the following tableX-ray diffraction peak shown in 1:

TABLE 1

[ example 2 ]

33.3g of aluminum sulfate [ Al ] is taken ₂ (SO ₄ ) ₃ ·18H ₂ O]Dissolving in 66.3mL of water, adding 5.2g of phosphoric acid (purity: 85 wt.%), 117.0g of tetrabutylammonium hydroxide (40 wt.% aqueous solution) and 102.6g of 1- (3-aminopropyl) imidazole under stirring to obtain a mixed solution, stirring for 3h, precipitating for 6h to obtain a solution A, adding 255mL of N, N-dibutylformamide and 48mL of cyclohexanone to the mixture A, stirring for 4.5h, and heat-treating at 80 ℃ for 12h to form a uniform mixture B, wherein Al is used as the catalyst ₂ O ₃ Aluminum source, in P ₂ O ₅ The mole ratio of the phosphorus source, the template agent and the solvent is as follows: al (Al) ₂ O ₃ ∶P ₂ O ₅ Total template R: total solvent S=1:0.9:10:80, template R _A (tetrabutylammonium hydroxide) template agent R _B (1- (3-aminopropyl) imidazole) =0.22 (molar ratio), solvent S ₁ (N, N-dibutylformamide) solvent S ₂ (cyclohexanone): solvent S3 (water) =1:0.3:48 (molar ratio); and (3) placing the mixture B into a crystallization kettle with a tetrafluoroethylene lining, crystallizing for 5 days at 140 ℃, filtering and washing a product, and drying at 80 ℃ for 24 hours to obtain an aluminum phosphate precursor, namely B for later use. Wherein, in the phosphoaluminate precursor B, al ₂ O ₃ ∶P ₂ O ₅ =1:0.92. The XRD pattern of aluminophosphate precursor B is shown in figure 2, i.e. comprising X-ray diffraction peaks as shown in table 2:

TABLE 2

[ example 3 ]

Weighing 24g of water, adding 3.1g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.6g of silica sol with the mass fraction of 40%, continuously stirring for 30min, adding 4.4g of 25wt% tetraethylammonium hydroxide solution, stirring for 3h at room temperature, adding 1g of 40wt% HF solution, uniformly stirring, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.23:1.1:1. The eutectic molecular sieve is the eutectic of the SCM-38 and the CHA structure molecular sieve, wherein the mass content of the SCM-38 is 42%, and the mass content of the CHA molecular sieve is 58%. The XRD pattern of this co-crystal molecular sieve is shown in FIG. 3, and as seen in FIG. 3, characteristic peaks for CHA molecular sieves occur at 2 theta of 9.49, 15.98, 20.56, 30.55, 31.35, with the strongest peak at 20.55, and further includes the main X-ray diffraction peak (i.e., the characteristic peak of SCM-38, calculated as 100% intensity of the strongest peak of the characteristic peaks of SCM-38 molecular sieves other than that of CHA molecular sieves in Table 3) as shown in Table 3, and further includes characteristic peaks for SCM-38 also occurring at 2 theta of 14.33, 21.38, 21.85, 27.31, 28.72:

TABLE 3 Table 3

[ example 4 ]

Weighing 12g of water, adding 1.75g of pseudo-thin aluminum hydrateStone and 6g of phosphoaluminate precursor A, stirring for 2 hours at room temperature; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.9g of silica sol with the mass fraction of 40%, adding 3.5g of tetraethylammonium hydroxide solution with the mass fraction of 25wt% after 30min, stirring for 3h at room temperature, adding 0.43g of HF solution with the mass fraction of 40wt%, stirring uniformly, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.11:1:1. The eutectic molecular sieve is the eutectic of the SCM-38 and the CHA structure molecular sieve, wherein the mass content of the SCM-38 is 22 percent, and the mass content of the CHA molecular sieve is 78 percent. The XRD pattern of the co-crystal molecular sieve exhibited characteristic peaks for CHA molecular sieves at 9.51, 15.96, 20.56, 30.51, 31.33, with the strongest peak at 20.56, and further included the main X-ray diffraction peaks (i.e., characteristic peaks for SCM-38, calculated as 100% intensity of the strongest peak of the characteristic peaks for SCM-38 molecular sieves other than the characteristic peaks for CHA molecular sieves in Table 4) as shown in Table 4, and further included characteristic peaks for SCM-38, also exhibited at 14.35, 21.41, 21.82, 27.30, 28.75 for 2 theta:

TABLE 4 Table 4

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.22	100
10.83	48
		11.57	22

[ example 5 ]

Weighing 24g of water, adding 3.7g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then 6.9g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide is added, stirring is continued for 1h, 1.1g of silica sol with the mass fraction of 40% is added, after 30min, 4.4g of tetraethylammonium hydroxide solution with the mass fraction of 25% is added, stirring is carried out for 3h at room temperature, 1g of HF solution with the mass fraction of 40% is added, and the mixture is uniformly stirred and then is filled into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 48 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.42:1.15:1. The eutectic molecular sieve is the eutectic of SCM-38 and CHA structure molecular sieve, wherein the mass content of SCM-38 is 13%, and the mass content of CHA molecular sieve is 87%. The XRD spectrum of this co-crystal molecular sieve exhibited characteristic peaks for CHA molecular sieves at 9.50, 15.97, 20.55, 30.51, 31.35, with the strongest peak at 20.55, and also included the main X-ray diffraction peaks as shown in Table 5 (i.e., characteristic peaks for SCM-38, calculated as 100% intensity of the strongest peak of the characteristic peaks for SCM-38 molecular sieves other than that for CHA molecular sieves in Table 5), and further included characteristic peaks for SCM-38 at 14.30, 21.38, 21.86, 27.35, 28.70 for 2 theta:

TABLE 5

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.22	100
10.83	56
		11.61	30

[ example 6 ]

28g of water is weighed, 4.3g of aluminum isopropoxide and 6g of aluminophosphate precursor A are added, and the mixture is stirred for 2 hours at room temperature; then 8.2g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide is added, stirring is continued for 1h, then 1.73g of silica sol with the mass fraction of 40% is added, after 30min, 6.6g of tetraethylammonium hydroxide solution with the mass fraction of 25% is added, stirring is carried out at room temperature for 3h, then 1.3g of HF solution with the mass fraction of 40% is added, and the mixture is uniformly stirred and then filled into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 36h; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.63:1.2:1. Wherein, the mass content of SCM-38 is 11%, and the mass content of CHA molecular sieve is 89%. The XRD pattern of the co-crystal molecular sieve exhibited characteristic peaks of CHA molecular sieve at 9.51, 15.97, 20.55, 30.52, 31.35, with the strongest peak at 20.55, and also included the main X-ray diffraction peaks (i.e., characteristic peaks of SCM-38, calculated as 100% intensity of the strongest peak of the characteristic peaks of SCM-38 molecular sieve other than characteristic peaks of CHA molecular sieve in Table 6) as shown in Table 6, and further included characteristic peaks of SCM-38 at 14.28, 21.37, 21.84, 27.36, 28.71 for 2 theta:

TABLE 6

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.23	100
10.83	55
		11.61	32

[ example 7 ]

Weighing 24g of water, adding 3.1g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.6g of silica sol with the mass fraction of 40%, adding 2.73g of 25wt% tetramethylammonium hydroxide solution after 30min, stirring for 3h at room temperature, adding 1g of 40wt% HF solution, stirring uniformly, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.21:1:1. Wherein, the mass content of SCM-38 is 45%, and the mass content of CHA molecular sieve is 55%. The XRD pattern of the co-crystal molecular sieve exhibited characteristic peaks of CHA molecular sieves at 9.50, 15.98, 20.53, 30.51, 31.36, with the strongest peak at 20.53, and further included the main X-ray diffraction peaks (i.e., characteristic peaks of SCM-38, calculated as 100% of the intensity of the strongest peak of the characteristic peaks of SCM-38 molecular sieves other than that of CHA molecular sieves in Table 7) as shown in Table 7, and further included characteristic peaks of SCM-38 at 14.34, 21.39, 21.84, 27.28, 28.68 for 2 theta:

TABLE 7

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.25	100
10.81	53
		11.60	21

[ example 8 ]

Weighing 24g of water, adding 3.1g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.6g of silica sol with the mass fraction of 40%, adding 6.1g of 25wt% tetrapropylammonium hydroxide solution after 30min, stirring for 3h at room temperature, adding 1g of 40wt% HF solution, stirring uniformly, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.22:1.1:1. Wherein, the mass content of SCM-38 is 39%, and the mass content of CHA molecular sieve is 61%. The XRD pattern of the co-crystal molecular sieve exhibited characteristic peaks for CHA molecular sieves at 9.55, 15.98, 20.60, 30.49, 31.31, with the strongest peak at 20.60, and further included the major X-ray diffraction peaks (i.e., characteristic peaks for SCM-38, calculated as 100% intensity of the strongest peak of the characteristic peaks for SCM-38 molecular sieves other than the characteristic peaks for CHA molecular sieves in Table 8) as shown in Table 8, and further included characteristic peaks for SCM-38, also exhibited at 14.30, 21.39, 21.85, 27.34, 28.76 for 2 theta:

TABLE 8

[ example 9 ]

28g of water is weighed, 3.28g of pseudo-boehmite and 6g of phosphoaluminate precursor A are added, and the mixture is stirred for 2 hours at room temperature; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.6g of silica sol with the mass fraction of 40%, adding 6.6g of 25wt% tetraethylammonium hydroxide solution after 30min, stirring for 3h at room temperature, adding 1g of 40wt% HF solution, stirring uniformly, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.24:1.2:1. Wherein, the mass content of SCM-38 is 35%, and the mass content of CHA molecular sieve is 65%. The co-crystal molecular sieve exhibited characteristic peaks for CHA molecular sieves at 2θ of 9.57, 15.99, 20.62, 30.48, 31.32, with the strongest peak at 20.62, and further included the main X-ray diffraction peaks (i.e., SCM-38 characteristic peaks, calculated as 100% intensity of the strongest peak of the characteristic peaks of SCM-38 molecular sieves other than the characteristic peaks for CHA molecular sieves in table 9) as shown in table 9, and further included the characteristic peaks for SCM-38 also exhibited at 2θ of 14.31, 21.39, 21.85, 27.35, 28.74:

TABLE 9

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.18	100
10.84	52
		11.60	25

[ example 10 ]

24g of water, 2.73g of aluminophosphate precursor B and stirring for 2 hours at room temperature are weighed; then adding 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, continuously stirring for 1h, adding 0.6g of silica sol with the mass fraction of 40%, adding 4.4g of 25wt% tetraethylammonium hydroxide solution after 30min, stirring for 3h at room temperature, adding 1g of 40wt% HF solution, stirring uniformly, and filling into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 24 hours; cooling, centrifugal separating, washing (centrifugal washing operation is repeated for 2-3 times), drying to obtain eutectic molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.21:1.1:1. Wherein, the mass content of SCM-38 is 38%, and the mass content of CHA molecular sieve is 62%. The XRD pattern of the eutectic molecular sieve is shown in figure 4. As can be seen from fig. 4, characteristic peaks of CHA molecular sieves occur at 2θ of 9.54, 15.98, 20.53, 30.50, 31.36, with the strongest peak at 20.53, and further including the main X-ray diffraction peak (i.e., SCM-38 characteristic peak, calculated as 100% of the intensity of the strongest peak in the characteristic peaks of SCM-38 molecular sieves other than the characteristic peaks of CHA molecular sieves in table 10) as shown in table 10, and further including the characteristic peaks of SCM-38 also occurring at 2θ of 14.31, 21.38, 21.81, 27.30, 28.72:

table 10

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		7.19	100
10.80	47
		11.59	19

Comparative example 1

Weighing 24g of water, adding 3.1g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then, 1.8g of 4wt% (40 wt% silica sol was diluted again by 10 times) of silica sol was added, and after stirring uniformly, 4.75g of 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide was added, then, 4.4g of 25wt% tetraethylammonium hydroxide aqueous solution was added, after stirring at room temperature for 4 hours, 1g of 40wt% HF solution was added, and after stirring uniformly, the mixture was charged into an autoclave with a tetrafluoroethylene lining. Crystallizing at 140 ℃ for 66 hours; then heating to 180 ℃, and crystallizing at the temperature for 8 hours; separating and washing after cooling (centrifugal washing operation is repeated for 2-3 times), drying to obtain SCM-38 molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =0.07:1.13:1. The XRD pattern of the molecular sieve is shown in fig. 5, i.e., includes X-ray diffraction peaks as shown in table 11:

TABLE 11

2θ(o)	Relative strength [ (I/I0)×100]
		7.23	100
10.82	20
		11.63	8
14.35	21
		21.41	14
21.85	27
		27.33	12
28.75	29

As can be seen from fig. 5 and table 11, SCM-38 has characteristic peaks including 2θ=7.20±0.1, 10.81±0.1, 11.60±0.1, and further includes characteristic peaks appearing at 2θ of 14.32±0.1, 21.39 ±0.1, 21.83±0.1, 27.31±0.1, 28.72±0.1.

Comparative example 2

Weighing 24g of water, adding 3.1g of aluminum isopropoxide and 6g of aluminophosphate precursor A, and stirring for 2 hours at room temperature; then adding 2.3g 40wt% silica sol, stirring uniformly, adding 4.75g6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide, then adding 4.4g 25wt% tetraethylammonium hydroxide aqueous solution, stirring at room temperature for 4h, adding 1g40wt% HF solution, stirring uniformlyAnd then the mixture is put into an autoclave with a tetrafluoroethylene lining. Crystallizing at 180 ℃ for 15 hours; separating and washing (centrifugal washing operation is repeated for 2-3 times) after cooling, and drying to obtain CHA structure molecular sieve, its chemical composition is calculated as SiO in mole ratio ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ =1.01:1.5:1. The XRD pattern of the molecular sieve is shown in fig. 6, i.e. comprising X-ray diffraction peaks as shown in table 12:

table 12

2θ(°)	Relative strength, [ (I/I) ₀ )×100]
		9.49	88
12.81	14
		14.07	15
15.98	42
		18.00	30
20.55	100
		25.23	38
25.82	23
		30.53	37
31.30	27

As can be seen from fig. 6 and table 12, the eutectic material obtained in comparative example 2 does not have the characteristic peak of SCM-38, but only has the characteristic peak of CHA molecular sieve, unlike the eutectic molecular sieve of the present invention.

Claims

1. The eutectic molecular sieve is characterized in that the eutectic molecular sieve is a eutectic molecular sieve of an SCM-38 molecular sieve and a CHA molecular sieve, and the chemical composition comprises the following components in mole ratio: siO (SiO) ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ The XRD pattern of the eutectic molecular sieve comprises X-ray diffraction peaks at 7.20+/-0.1,9.49 +/-0.1, 10.81+/-0.1, 11.60+/-0.1, 15.98+/-0.1, 20.56+/-0.1, 30.55+/-0.1 and 31.32 +/-0.1 of 2 theta.

2. The eutectic molecular sieve of claim 1, wherein the eutectic molecular sieve has an XRD pattern in which X-ray diffraction peaks, i.e. characteristic peaks of SCM-38 molecular sieve, appear at 7.20 ± 0.1, 10.81 ± 0.1, 11.60 ± 0.1, wherein 2Θ is the strongest peak at 7.20 ± 0.1 of the characteristic peaks of SCM-38 molecular sieve;

preferably, the XRD pattern of the co-crystal molecular sieve comprises X-ray diffraction peaks as shown in the following table, calculated as 100% intensity of the strongest of the characteristic peaks of the SCM-38 molecular sieve:

3. The eutectic molecular sieve of claim 1 or 2, wherein the characteristic peaks of SCM-38 molecular sieve in the XRD pattern of the eutectic molecular sieve further comprise X-ray diffraction peaks at 14.32±0.1, 21.39 ±0.1, 21.83±0.1, 27.31±0.1, 28.72±0.1;

4. A co-crystal molecular sieve according to any one of claims 1 to 3, wherein the chemical composition of the co-crystal molecular sieve comprises, in molar ratio: siO (SiO) ₂ ∶Al ₂ O ₃ ∶P ₂ O ₅ ＝(0.11-0.80)∶(0.88-1.30)∶1。

5. A co-crystal molecular sieve according to any one of claims 1 to 3, wherein in the co-crystal molecular sieve, CHA molecular sieve comprises 1% to 99% by mass, further 10% to 90% by mass, and SCM-38 molecular sieve comprises 1% to 99% by mass, further 10% to 90% by mass, of the co-crystal molecular sieve.

6. The method of making the co-crystal molecular sieve of any of claims 1-5, comprising:

a) Mixing an aluminophosphate precursor, a silicon source, an organic base R1, an organic matter R2, a fluorine source, water and optionally an aluminum source A to obtain a synthetic mother solution;

wherein, the organic alkali R1 is one or more of tetramethyl ammonium hydroxide, tetraethyl ammonium hydroxide and tetrapropyl ammonium hydroxide; the organic matter R2 is 6-N, N-dimethylaminohexyl-2-hydroxyethyl dimethyl ammonium bromide;

the aluminophosphate precursor has the formula of Al ₂ O ₃ ∶xP ₂ O ₅ "the chemical composition is shown, wherein x is more than or equal to 0.8 and less than or equal to 2; the XRD pattern of the aluminophosphate precursor mainly comprises X-ray diffraction peaks shown in the following table:

7. The method of preparing according to claim 6, wherein in step a), the XRD pattern of the aluminophosphate precursor further comprises X-ray diffraction peaks as shown in the following table:

8. The method of preparing according to claim 6 or 7, wherein in step a), the XRD pattern of the aluminophosphate precursor further comprises X-ray diffraction peaks as shown in the following table:

9. the preparation method according to claim 6, wherein the molar ratio of each material in the synthetic mother liquor is as follows: the aluminum source A is Al ₂ O ₃ Meter, silicon source with SiO ₂ Metering the aluminophosphate precursor to A1 ₂ O ₃ 、P ₂ O ₅ Meter, organic base R ₁ R is organic matter ₂ Fluorine source in HF and water in H ₂ O meter, (0.08-0.8) SiO ₂ ∶(0.88-1.3)Al ₂ O ₃ ∶1P ₂ O ₅ ∶(0.3-0.8)R ₁ ∶(1-2)R ₂ ∶(0.5-1.8)HF∶(50-130)H ₂ O, preferably (0.11-0.8) SiO ₂ ∶(0.88-1.3)Al ₂ O ₃ ∶1P ₂ O ₅ ∶(0.3-0.8)R ₁ ∶(1-2)R ₂ ∶(0.5-1.8)HF∶(50-130)H ₂ O。

10. The preparation method according to claim 6, wherein the aluminum source A is one or more selected from the group consisting of pseudo-boehmite, aluminum isopropoxide, aluminum sol and aluminum oxide; the silicon source is selected from one or more of silica sol and fumed silica; the fluorine source is selected from aqueous HF solutions.

11. The process according to any one of claims 6 to 10, characterized in that in step b), the crystallization conditions are as follows: the crystallization temperature is 160-210 ℃, the crystallization time is 8-100 hours, preferably 170-200 ℃, and the crystallization time is 20-84 hours.

12. A eutectic molecular sieve composition comprising the eutectic molecular sieve of any one of claims 1-5 or prepared according to the method of any one of claims 6-11, and a binder.

13. Use of the co-crystal molecular sieve of any one of claims 1 to 5, or the co-crystal molecular sieve prepared according to the method of any one of claims 6 to 11, or the co-crystal molecular sieve composition of claim 12 in an adsorbent or catalyst.