Recry-beta molecular sieves and catalysts, methods for their preparation and their use in hydrocarbon conversion reactions

Abstract

The application relates to the field of catalysts and discloses a Recry-Beta molecular sieve and a catalyst, a preparation method thereof and application thereof in hydrocarbon conversion reactions, wherein the preparation method of the molecular sieve comprises the following steps: performing acid pickling and aluminum removal treatment on H-Beta molecular sieve to obtain Si-Beta molecular sieve; mixing the Si-Beta molecular sieve, a template agent and water and performing crystallization to obtain the Recry-Beta molecular sieve; the particle size of the H-Beta molecular sieve is below 90 nm, and the molar ratio of the template agent to the Si-Beta molecular sieve in terms of SiO2 is 0.08-0.25. The prepared molecular sieve can promote the interaction between Zr and the framework elements of the molecular sieve, is suitable for the reaction of preparing 1,3-butadiene from ethanol-acetaldehyde, and exhibits excellent catalytic performance, and the conversion rate of raw materials, the selectivity of 1,3-butadiene and the stable running time are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of catalysts, specifically to a Recry-Beta molecular sieve and its preparation method, a catalyst and its preparation method, and the application of the Recry-Beta molecular sieve or the catalyst in hydrocarbon conversion reactions. Background Technology

[0002] Butadiene (1,3-Butadiene, BD) is an important basic raw material in petrochemicals and an intermediate monomer in synthetic rubber, playing a crucial role in industrial production, especially in rubber manufacturing and the automotive industry. With the development of naphtha cracking technology for ethylene production, approximately 97% of the world's butadiene is produced through a process that extracts 1,3-butadiene as a byproduct from C4 fractions. However, with increasingly scarce petroleum resources and rising oil prices, the petroleum-based butadiene production process is bound to be affected. Therefore, developing non-petroleum-based butadiene production processes is urgently needed. In recent years, with the continuous maturation of bioethanol production technology and the gradual increase in production scale, the ethanol-based butadiene production process represents a new alternative to the petroleum-based route. There are two processes for producing butadiene (ETB) from ethanol: the one-step process (Makshina EV, Dusselier M, Janssens W, et al. Chemical Society Reviews, 2014, 43(22):7917-7953.), namely the Lebedev process developed in the 1920s, which uses ethanol as a raw material to produce butadiene. This process has low butadiene selectivity but high acetaldehyde selectivity. Butadiene selectivity can be improved to 30-40% by recycling acetaldehyde. The two-step process (Alessandro M, Oberto C. Process for the manufacture of diolefins from alcohols and aldehydes. US2297424A. 1942.; Dunn JT, Toussaint W J. Process for making diolefins. US2421361A[P]. 1947.), namely the Ostromyslensky process developed in 1942, involves partial dehydrogenation of ethanol to produce acetaldehyde in the first reactor, and the conversion of the ethanol-acetaldehyde mixture to butadiene in the second reactor, achieving a selectivity of up to 60%. The two-step process has a more significant advantage.

[0003] Both the one-step and two-step processes include the following five reaction steps: ① ethanol dehydrogenation to acetaldehyde; ② acetaldehyde undergoes an aldol condensation reaction to generate butyrolaldehyde; ③ butyrolaldehyde is dehydrated to generate crotonaldehyde; ④ crotonaldehyde and ethanol undergo an MPV reaction to generate crotonol and acetaldehyde; ⑤ crotonol is dehydrated to generate butadiene. Among these, Ag and Cu are commonly used as catalysts for the ethanol dehydrogenation to acetaldehyde reaction, which can meet the needs of industrial production. Regarding the requirements for the second reaction in the two-step process, existing research results indicate that elements such as Ta, Zr, Zn, and Mg can enter the molecular sieve framework or pores, exhibiting L-acid centers, which are active centers in aldol condensation and MPV reduction reactions (T.-W. Kim, J.-W. Kim, C.-U. Kim, Chem. Eng. J. 2015, 278, 217-223); Si-OH on the surface of SiO2, MWW, and Beta molecular sieves exhibits weak Brønsted acid, serving as active centers for dehydration reactions (M. Gao, H. Jiang, M. Zhang, Catal. Surveys Asia 2020, 1-8; VLSushkevich, IIIvanova, E. Taarning, Green Chem. 17(4)(2015)2552–2559.; PI Kyriienko, OV Larina, SOSoloviev, SMO Orlyk, S. Dzwigaj. Catal. Commun. 77(2016)123–126.; Minhua Zhang, etc. Microporous and Mesoporous Materials 326(2021)111359). Among them, the Zr-Beta catalyst containing metallic zirconium with pure silica beta molecular sieve as support has a high butadiene selectivity, with a feed conversion rate of 43.2% and a butadiene selectivity of 73.9%. However, the catalyst has poor activity stability and is prone to carbon deposition, and can only operate for a few hours. This is because the structure of the beta molecular sieve is damaged in the two processes of dealumination and metal loading, and the crystallinity is greatly reduced. Therefore, how to maintain the good crystallinity of the molecular sieve is the key factor to improve the performance of the catalyst. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art and provide a highly crystalline Beta molecular sieve (denoted as Recry-Beta molecular sieve) and a catalyst prepared based on the Recry-Beta molecular sieve, which exhibits excellent catalytic performance in the reaction of ethanol-acetaldehyde to prepare 1,3-butadiene.

[0005] To achieve the above objectives, a first aspect of the present invention provides a method for preparing Recry-Beta molecular sieves, the method comprising:

[0006] (1) H-Beta molecular sieve was acid-washed and dealuminized to obtain Si-Beta molecular sieve;

[0007] (2) Si-Beta molecular sieve, template agent and water are mixed and then crystallized to obtain the Recry-Beta molecular sieve;

[0008] The particle size of the H-Beta molecular sieve is below 90 nm.

[0009] The molar ratio of the template agent to the Si-Beta molecular sieve (calculated as SiO2) is 0.08-0.25.

[0010] A second aspect of the present invention provides a Recry-Beta molecular sieve prepared by the method described above.

[0011] A third aspect of the present invention provides a method for preparing a catalyst, the method comprising: loading Zr onto a Recry-Beta molecular sieve as described above, and then subjecting it to drying and calcination to obtain the catalyst.

[0012] A fourth aspect of the present invention provides a catalyst comprising the Recry-Beta molecular sieve as described above and a zirconium-containing species supported on the Recry-Beta molecular sieve.

[0013] The fifth aspect of the present invention provides the application of the Recry-Beta molecular sieve or the catalyst described above in hydrocarbon conversion reactions, preferably in the reaction of ethanol-acetaldehyde to prepare 1,3-butadiene.

[0014] This invention prepares small-particle-size Si-beta molecular sieves by acid elution and dealuminization of small-particle-size H-beta molecular sieves, and then crystallizes them to obtain the Beta molecular sieve (denoted as Recry-Beta molecular sieve) described in this invention. The Recry-Beta molecular sieve has a small particle size, a large number of silanol groups and a high degree of crystallinity, which can promote the interaction between metals and molecular sieve framework elements, improve metal dispersion, improve catalyst activity and selectivity, and extend catalyst operating time.

[0015] The Zr-containing catalyst prepared by the Recry-Beta molecular sieve by the method of the present invention can be used in the reaction of ethanol-acetaldehyde to prepare 1,3-butadiene. Moreover, the catalyst exhibits excellent catalytic performance, significantly improving the conversion rate of raw materials, the selectivity of 1,3-butadiene, and the stable operating time. Attached Figure Description

[0016] Figure 1These are the XRD patterns of the molecular sieves prepared in Examples 1-5 of this invention;

[0017] Figure 2 This is a TEM image of the H-Beta molecular sieve prepared in Example 1 of this invention;

[0018] Figure 3 This is a TEM image of the Si-Beta molecular sieve prepared in Example 2 of this invention;

[0019] Figure 4 This is a TEM image of the Recry-Beta molecular sieve prepared in Example 3 of this invention;

[0020] Figure 5 This is a TEM image of the Recry-Beta molecular sieve prepared in Example 4 of this invention;

[0021] Figure 6 This is a TEM image of the Recry-Beta molecular sieve prepared in Example 5 of this invention;

[0022] Figure 7 These are isotherm curves of the molecular sieves prepared in Examples 1-3 of this invention;

[0023] Figure 8 The XRD patterns are of the catalysts prepared in Example 1 and Comparative Example 1 of this invention.

[0024] Figure 9 The molecular sieves or catalysts prepared in Examples 1-3, Example 1, and Comparative Example 1 of this invention are for the purpose of preparation. 29 Si MAS NMR spectrum;

[0025] Figure 10 The UV-Vis images are of the catalysts prepared in Example 1 and Comparative Example 1 of this invention.

[0026] Figure 11 XPS images of the catalysts prepared in Example 1 and Comparative Example 1 of this invention. Detailed Implementation

[0027] 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.

[0028] The technical terms used in this invention, where defined, shall be used according to their definitions, and where not defined, shall be understood according to their common meaning in the art.

[0029] The first aspect of this invention provides a method for preparing Recry-Beta molecular sieves, the method comprising:

[0030] (1) H-Beta molecular sieve was acid-washed and dealuminized to obtain Si-Beta molecular sieve;

[0031] (2) Si-Beta molecular sieve, template agent and water are mixed, and then crystallized and calcined to obtain the Recry-Beta molecular sieve;

[0032] The H-Beta molecular sieve has a particle size of less than 90 nm (for example, it can be 20, 30, 40, 50, 60, 70, 80, 90 nm or less, or any range between any two values).

[0033] The molar ratio of the template agent to the Si-Beta molecular sieve (based on SiO2) is 0.08-0.25 (for example, it can be 0.08, 0.1, 0.12, 0.14, 0.15, 0.16, 0.17, 0.18, 0.2, 0.25, or any range between any two values, preferably 0.13-0.18).

[0034] Preferably, the particle size of the H-Beta molecular sieve is 20-50 nm.

[0035] In this invention, the particle size of the molecular sieve and the catalyst can be determined by transmission electron microscopy.

[0036] The H-beta molecular sieve can be obtained commercially or prepared in-house. Its preparation method can be found in patent CN1324762A, which is incorporated herein by reference in its entirety.

[0037] In a preferred embodiment of the present invention, under alkaline conditions, a silicon source, an aluminum source, and a template agent are mixed and then subjected to hydrothermal crystallization, drying, ammonium exchange, and calcination to obtain H-beta molecular sieves. The order of the ammonium exchange and calcination treatments is not particularly limited.

[0038] The alkaline conditions can be provided by alkaline substances commonly used in the art, such as sodium hydroxide.

[0039] The silicon source can be a conventional silicon source in the art, such as silicon dioxide or silicone.

[0040] Preferably, the aluminum source is selected from one or more of alkali metal (metaseo)aluminates (such as sodium aluminate), hydrated alumina, aluminum hydroxide, hydrated aluminum chloride, and boehmite.

[0041] Preferably, the template agent has at least one of the structures shown in formula (1):

[0042]

[0043] R1, R2, R3 and R4 are each independently selected from alkyl groups having 1 to 4 carbon atoms. Preferably, R1, R2, R3 and R4 are each independently selected from one or more of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl, more preferably methyl or ethyl.

[0044] X - This includes hydroxide ions or halide anions.

[0045] Preferably, the template agent is tetramethylammonium hydroxide and / or tetraethylammonium hydroxide.

[0046] It should be understood that the hydrothermal crystallization is carried out under aqueous conditions.

[0047] Preferably, the amounts of each component are such that, in molar amounts, the SiO2 / Al2O3 ratio is 10-50 (e.g., it can be 10, 20, 30, 40, 50, or any range between any two values), the H2O / SiO2 ratio is 5-8 (e.g., it can be 5, 6, 7, 8, or any range between any two values), the template agent / SiO2 ratio is 0.05-0.15 (e.g., it can be 0.05, 0.08, 0.1, 0.12, 0.15, or any range between any two values), and the OH... - / SiO2 is 0.1-0.15 (for example, it can be 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, or any range between any two values).

[0048] Preferably, hydrothermal crystallization is carried out at 120-200°C and under autogenous pressure for 5-120 hours, more preferably at 80-138°C (preferably 110-130°C) and under autogenous pressure for 5-72 hours (preferably 16-32 hours), and then at 140-200°C (preferably 140-160°C) and under autogenous pressure for 5-72 hours (preferably 36-56 hours).

[0049] The drying and ammonium exchange methods are conventional in the art and will not be described in detail here. The calcination conditions can be, for example, a temperature of 500-600℃ and a time of 3-5 hours.

[0050] Preferably, the acid leaching and dealuminization conditions result in a silica content of 99.5% or higher in the obtained Si-Beta molecular sieve, such as 99.5%, 99.6%, 99.7%, 99.8%, 99.9 wt% or higher, or any range between any two values, thereby reducing the impurity content of the catalyst.

[0051] Preferably, the pickling conditions include: a temperature of 60-90℃, an acid selected from one or more of nitric acid, hydrochloric acid, and sulfuric acid, and a pickling solution concentration generally of 1-15 mol / L. The number of acid exchanges and the time depend on the silica (or alumina) content in the molecular sieve during the actual operation.

[0052] The material obtained after acid washing can be further processed to obtain the Si-Beta molecular sieve. The subsequent processing operations can include filtration, washing and drying, etc., and can refer to conventional operations in the field.

[0053] Preferably, the crystallinity of the Si-Beta molecular sieve is 60-90%, for example, it can be 60, 65, 70, 75, 80, 85, 90% or any range between any two values, more preferably 70-85%.

[0054] The crystallinity was determined by XRD and calculated as the sum of the areas of the characteristic peaks at 2θ = 7-9° and 22-23°. The standard sample was the H-beta molecular sieve prepared in Preparation Example 1 of this invention.

[0055] Preferably, the BET specific surface area S of the Si-Beta molecular sieve is... BET 450-680m 2 / g, for example, can be 450, 480, 500, 550, 600, 650, 680m 2 / g and any range between any two values, more preferably 480-650m 2 / g.

[0056] Preferably, the total pore volume V of the Si-Beta molecular sieve 总 The value is 0.25-0.85cm. 3 / g, for example, can be 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.85cm 3 / g and any range between any two values, more preferably 0.45-0.7cm 3 / g.

[0057] Preferably, the packing pore volume V of the Si-Beta molecular sieve meso It is 0.2-0.55cm 3 / g, for example, can be 0.23, 0.25, 0.3, 0.4, 0.5, 0.55cm 3 / g and any range between any two values, more preferably 0.26-0.48cm 3 / g.

[0058] Specific surface area, pore volume, and pore volume can be measured using a nitrogen adsorption analyzer.

[0059] Preferably, the molar ratio of the template agent to the Si-Beta molecular sieve (based on SiO2) is 0.1-0.2 (for example, it can be 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, or any range between any two values). The template agent is described in the section on template agents for preparing H-beta molecular sieves, and will not be repeated here.

[0060] Preferably, the molar ratio of water to Si-Beta molecular sieve (calculated as SiO2) is 3-10, for example, it can be 3, 4, 6, 8, 10, or any range between any two values, more preferably 5-8.

[0061] Preferably, the crystallization conditions include: a crystallization temperature of 100-300℃, more preferably 110-150℃; and a crystallization time of 12h-120h, more preferably 24h-72h. It should be understood that the pressure is autogenous pressure.

[0062] Preferably, the crystallization method is a two-step crystallization, more preferably, crystallization at 110-130℃ for 18-36 hours, and then crystallization at 130-150℃ for 18-36 hours.

[0063] Preferably, the calcination conditions include: a calcination temperature of 400-650℃, more preferably 500-600℃; and a calcination time of 2-8 hours, preferably 3-5 hours.

[0064] A second aspect of the present invention provides a Recry-Beta molecular sieve prepared by the method described above.

[0065] Preferably, the silica-alumina ratio of the Recry-Beta molecular sieve is 800 or higher, such as 800, 1000, 1500, 2000, 2500 or higher, or any range between any two values, more preferably 1200-2500.

[0066] Preferably, the crystallinity of the Recry-Beta molecular sieve is 50-100%, for example, it can be 50, 60, 65, 70, 75, 80, 85, 90, 100% and any range between any two values, more preferably 55-80%.

[0067] Preferably, the BET specific surface area S of the Recry-Beta molecular sieve is... BET 450-680m 2 / g, for example, can be 450, 480, 500, 550, 600, 650, 680m 2 / g and any range between any two values, more preferably 500-660m 2 / g.

[0068] Preferably, the total pore volume V of the Recry-Beta molecular sieve 总 The value is 0.25-0.85cm. 3 / g, for example, can be 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.85cm 3 / g and any range between any two values, more preferably 0.45-0.7cm 3 / g.

[0069] Preferably, the packing pore volume V of the Recry-Beta molecular sieve meso It is 0.2-0.55cm 3 / g, for example, can be 0.23, 0.25, 0.3, 0.4, 0.5, 0.55cm 3 / g and any range between any two values, more preferably 0.26-0.48cm 3 / g.

[0070] A third aspect of the present invention provides a method for preparing a catalyst, the method comprising: loading Zr onto a Recry-Beta molecular sieve as described above, and then subjecting it to drying and calcination to obtain the catalyst.

[0071] The catalyst described in this invention can be prepared using conventional methods in the art. For example, it can be prepared using a conventional impregnation method (i.e., an equal-volume impregnation method), or it can be prepared using an ion exchange method. The impregnation method involves contacting a Zr precursor solution with a Recry-Beta molecular sieve. The Zr precursor can be a water-soluble or alcohol-soluble compound of Zr, such as one or more of nitrates (e.g., ZrO(NO3)2·2H2O), chlorides, and acetates. The impregnation method can be a conventional method in the art and will not be described in detail here.

[0072] Preferably, the loading method includes impregnating Recry-Beta molecular sieves with a Zr precursor solution.

[0073] Preferably, the impregnation conditions include: pH 3-12, such as 3, 5, 7, 9, 11, 12 and any range between any two values, more preferably 7-11; and temperature 20-60℃, such as 20, 30, 40, 50, 60℃ and any range between any two values.

[0074] The pH of the zirconium precursor solution can be adjusted to a range of 7-11 using an alkaline substance. Preferably, the alkaline substance is ammonia and / or ammonium salts (such as ammonium chloride, ammonium sulfate, ammonium nitrate, etc.).

[0075] The impregnation time can be appropriately selected according to the degree of dispersion of the precursor. In the preferred case, the impregnation time is 1-5 hours.

[0076] Furthermore, the amount of solvent in the Zr precursor solution must be sufficient to ensure both the complete dissolution of the Zr precursor in the solvent and the adequate dispersion of the molecular sieve. Preferably, the amount of solvent in the Zr precursor solution is 10-400 ml, more preferably 20-50 ml, compared to 1 g of Recry-Beta molecular sieve. The solvent can be at least one of water, ethanol, and propanol.

[0077] Preferably, the amount of each component is such that, based on the total weight of the catalyst, the content of Recry-Beta molecular sieve is 95-99.9 wt%, for example, it can be 95, 96, 97, 98, 99, 99.5, 99.9 wt% or more, or any range between any two values, more preferably 97-99.5 wt%, and the content of zirconium-containing species, calculated as Zr oxide, is 0.1-5 wt%, for example, it can be 0.1, 0.5, 1, 2, 3, 4, 5 wt% or more, or any range between any two values, more preferably 0.5-3 wt%.

[0078] It should be understood that the zirconium-containing species may be zirconium oxides or other forms of zirconium.

[0079] There are no particular restrictions on the drying conditions, such as drying at 60-120°C, and there are no particular restrictions on the drying time, as long as the weight is kept constant.

[0080] Preferably, the calcination conditions include: a temperature of 400-600℃ and a time of 1-6 hours.

[0081] A fourth aspect of the present invention provides a catalyst comprising the Recry-Beta molecular sieve as described above and an oxide of Zr supported on the Recry-Beta molecular sieve.

[0082] Preferably, based on the total weight of the catalyst, the content of Recry-Beta molecular sieve is 95-99.9 wt%, for example, it can be 95, 96, 97, 98, 99, 99.5, 99.9 wt% or more, or any range between any two values, more preferably 97-99.5 wt%, and the content of zirconium-containing species, calculated as Zr oxide, is 0.1-5 wt%, for example, it can be 0.1, 0.5, 1, 2, 3, 4, 5 wt% or more, or any range between any two values, more preferably 0.5-3 wt%.

[0083] In a preferred embodiment of the present invention, the present invention provides a catalyst having a crystallinity of 30-85%, for example, it can be any range of 30, 35, 40, 45, 50, 60, 65, 70, 75, 80, 85%, preferably 40-75%; and / or the catalyst having a silica-alumina ratio of 800 or higher, for example, it can be 800, 1000, 1500, 2000, 2500 or higher, preferably 1200-2500; and / or the catalyst having a BET specific surface area S BET 450-680m 2 / g, for example, can be 450, 480, 500, 550, 600, 650, 680m 2 / g and any range between any two values, preferably 480-650m. 2 / g; and / or the total pore volume V of the catalyst 总 It is 0.35-0.7cm 3 / g, for example, can be 0.35, 0.4, 0.5, 0.6, 0.7cm 3 / g and any range between any two values, preferably 0.44-0.65cm. 3 / g; and / or the packing pore volume V of the catalyst meso It is 0.1-0.7cm 3 / g, for example, can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7cm 3 / g and any range between any two values, preferably 0.2-0.55cm 3 / g.

[0084] The fifth aspect of the present invention provides the application of the Recry-Beta molecular sieve or the catalyst described above in hydrocarbon conversion reactions, preferably in the reaction of ethanol-acetaldehyde to prepare 1,3-butadiene.

[0085] The conditions for preparing 1,3-butadiene can be carried out with reference to existing technologies, with the aim of preparing 1,3-butadiene from ethanol-acetaldehyde.

[0086] According to the present invention, the conditions for the contact reaction of ethanol and acetaldehyde typically include reaction temperature and reaction pressure. The reaction temperature can be maintained at 250-450°C, preferably 250-400°C; the reaction pressure can be maintained at 0.1-4 MPa, preferably 0.1-1.5 MPa. The objective of the present invention can be achieved simply by using the catalyst described herein. From the perspective of further improving the catalytic activity of the catalyst, the amount of the catalyst is set based on the total amount of ethanol and acetaldehyde, so that the gas hourly space velocity (HSV) of the reactants is 0.1-9 h⁻¹. -1 (h -1 Preferably 0.1-6 hours -1 (h -1 The molar ratio of ethanol to acetaldehyde in the feed can be 1-12, preferably 1.5-5.

[0087] In the method of the present invention, the reaction for preparing 1,3-butadiene from ethanol can be carried out in various reactors conventionally used in the art, for example, including but not limited to at least one of a fixed bubble bed reactor, a fixed trickle bed reactor, and a slurry bed reactor.

[0088] The present invention will be described in detail below through embodiments.

[0089] (1) In the following examples, the particle size of the molecular sieve was analyzed by TEM.

[0090] (2) In the following examples, the crystallinity of the molecular sieve and the catalyst was analyzed by XRD, with the sum of the characteristic peak areas of 2θ = 7-9° / 22-23° of the H-Beta molecular sieve prepared in Example 1 as the benchmark.

[0091] (3) In the following embodiments, the specific surface area and pore volume of the molecular sieve and catalyst were measured according to the following analytical methods:

[0092] Equipment: Micromeritic ASAP2010 static nitrogen adsorption instrument.

[0093] Measurement conditions: Place the sample in the sample processing system and evacuate to 1.33 × 10⁻⁶ at 350°C. -2 The sample was purified by maintaining the temperature and pressure at 15 h. At liquid nitrogen temperature -196℃, the adsorption and desorption amounts of nitrogen on the purified sample under different specific pressures P / P0 were measured to obtain adsorption-desorption isotherms. The total specific surface area was then calculated using the two-parameter BET formula, and the total pore volume was calculated based on the adsorption amount at P / P0 = 0.98.

[0094] (4) In the following examples, a Rigaku Electric Co., Ltd. 3013 X-ray fluorescence spectrometer was used for silicon-to-aluminum ratio analysis. Test conditions: tungsten target, excitation voltage 40 kV, excitation current 50 mA. Experimental procedure: The catalyst sample was pressed into a tablet and mounted on the X-ray fluorescence spectrometer. Under X-ray irradiation, it emitted fluorescence. The fluorescence wavelength λ and the atomic number Z of the element had the following relationship: λ = K(Z - S). -2 K is a constant; the element can be identified simply by measuring the wavelength λ of the fluorescence. The intensity of the characteristic spectral lines of each element is measured using a scintillation counter and a proportional counter for quantitative or semi-quantitative elemental analysis.

[0095] In the following examples, all reagents and raw materials are either commercially available or prepared using existing methods.

[0096] Preparation Example 1

[0097] This preparation example illustrates the preparation method of H-beta molecular sieves.

[0098] 5.17 g of sodium aluminate solution (specific gravity 1.24 g / ml, NaOH mass fraction 15.65%, Al2O3 mass fraction 8.19%) was added to a 45 mL polytetrafluoroethylene container. Then, 9.33 g of an aqueous solution of template agent (tetraethylammonium hydroxide) (mass fraction 26.46%) was added and stirred for 30 minutes until homogeneous. Next, 10 g of solid silica gel (SiO2 mass fraction 99.30%) and 8.823 g of deionized water were added and stirred for 5 minutes to mix thoroughly. The molar ratios of the components were: SiO2 / Al2O3 = 25, H2O / SiO2 = 6.5, template agent / SiO2 = 0.1, OH... - / SiO2=0.12.

[0099] The above mixture was placed in a 45 mL PTFE-lined steel autoclave, capped, and sealed. The autoclave was placed in a rotating convection oven at 20 rpm and reacted at 120 °C for 24 h, then at 145 °C for 48 h. The autoclave was removed and rapidly cooled to room temperature. The mixture was separated using a 5000 rpm high-speed centrifuge, and the solid was collected, thoroughly washed with deionized water, and dried at 100 °C for 24 h to obtain the Beta-structured molecular sieve raw powder. After ammonium exchange and calcination at 550 °C for 4 h, the hydrogen form sample was obtained, designated as H-Beta molecular sieve.

[0100] The XRD pattern of this product is as follows: Figure 1 As shown, its crystallinity is defined as 100%; transmission electron microscopy image as follows. Figure 2 As shown, the molecular sieve particle size is in the range of 20-50 nm; the isotherm curve is shown in the figure. Figure 7 As shown, a hysteresis loop appears; 29Si MAS NMR image as follows Figure 9 As shown, characteristic peaks such as Si(3Si,1OH) (chemical shift -116), Si(4Si) (chemical shift -111), and Si(3Si,1Al) (chemical shift -101) appear.

[0101] The results for particle size, crystallinity, and silicon-to-aluminum ratio of the product are shown in Table 1, and the results for surface area and pore volume are shown in Table 2.

[0102] Preparation Example 2

[0103] This preparation example illustrates the preparation method of Si-beta molecular sieves.

[0104] The H-Beta molecular sieve prepared in Preparation Example 1 was mixed with a 13 mol / L HNO3 solution at 80 °C, acid-washed for 12 h, filtered and washed until pH = 4, then mixed with distillate at 80 °C and washed with water for 4 h. The dealuminized Beta molecular sieve was recovered by filtration, washed with distilled water until neutral, and dried at 80 °C for 24 h to obtain Si-Beta molecular sieve.

[0105] The XRD pattern of this product is as follows: Figure 1 As shown, the transmission electron microscope image is as follows: Figure 3 As shown, the isotherm curve is as follows: Figure 7 As shown, 29 SiMAS NMR image as follows Figure 9 As shown.

[0106] The results for particle size, crystallinity, and silicon-to-aluminum ratio of the product are shown in Table 1, and the results for surface area and pore volume are shown in Table 2.

[0107] Preparation Example 3

[0108] This preparation example illustrates the preparation method of the beta molecular sieve (denoted as Recry-Beta molecular sieve) described in this invention.

[0109] In a polytetrafluoroethylene container, the Si-Beta molecular sieve prepared in Preparation Example 2 was used as a raw material. A template agent and water were added, and crystallization was carried out. The crystallization method included reacting at 120°C for 24 hours under sealed conditions, followed by reacting at 145°C for 24 hours, to obtain molecular sieve raw powder (crystallinity 95.4%). After calcining the raw powder at 550°C for 4 hours to remove the template agent, the resulting sample was designated Recry-Beta molecular sieve-1. The molar ratio of each component was: H2O / Si-Beta = 6.5, template agent / Si-Beta = 0.16, where the molar amount of Si-Beta was calculated as silicon dioxide, and the template agent was tetramethylammonium hydroxide.

[0110] The obtained XRD pattern of the product is as follows Figure 1 As shown, the transmission electron microscope image is as follows: Figure 4 As shown, the isotherm curve is as follows: Figure 7 As shown, 29 Si MAS NMR image as follows Figure 9 As shown.

[0111] The results for particle size, crystallinity, and silicon-to-aluminum ratio of the product are shown in Table 1, and the results for surface area and pore volume are shown in Table 2.

[0112] Preparation Example 4

[0113] This preparation example illustrates the preparation method of the beta molecular sieve (denoted as Recry-Beta molecular sieve) described in this invention.

[0114] The Recry-Beta molecular sieve was prepared according to the method described in Preparation Example 3, except that the molar ratio of the template agent to the Si-Beta molecular sieve was 0.13, and the resulting sample was designated as Recry-Beta molecular sieve-2.

[0115] The obtained XRD pattern of the product is as follows Figure 1 As shown, the transmission electron microscope image is as follows: Figure 5 As shown in the figure. The crystallinity of the raw powder is 86.0%.

[0116] The results for particle size, crystallinity, and silicon-to-aluminum ratio of the product are shown in Table 1, and the results for surface area and pore volume are shown in Table 2.

[0117] Preparation Example 5

[0118] This preparation example illustrates the preparation method of the beta molecular sieve (denoted as Recry-Beta molecular sieve) described in this invention.

[0119] The Recry-Beta molecular sieve was prepared according to the method described in Preparation Example 3, except that the molar ratio of the template agent to the Si-Beta molecular sieve was 0.10, and the resulting sample was denoted as Recry-Beta molecular sieve-3.

[0120] The obtained XRD pattern of the product is as follows Figure 1 As shown, the transmission electron microscope image is as follows: Figure 6 As shown. The crystallinity of the raw powder is 71.5%.

[0121] The results for particle size, crystallinity, and silicon-to-aluminum ratio of the product are shown in Table 1, and the results for surface area and pore volume are shown in Table 2.

[0122] Table 1

[0123] name Silicon ratio / mol Particle size / nm Crystallinity / % silicon-aluminum ratio H-Beta / 20-50 100 20 Si-Beta / 20-50 73.9 2440 Recry-Beta-1 0.16 20-30 75.4 1240 Recry-Beta-2 0.13 20-30 72.9 1374 Recry-Beta-3 0.1 20-50 58.3 1470

[0124] As can be seen from the results in Table 1, as the modulus-to-silicon ratio increases, the crystallinity of Recry-Beta molecular sieves increases, while the particle size and silicon-to-aluminum ratio decrease further.

[0125] Table 2

[0126]

[0127] The results in Table 2 show that, compared to Si-Beta molecular sieves, Recry-Beta molecular sieves have a higher BET specific surface area SE. BET and micropore volume V micro All increased, indicating a more complete molecular sieve structure; except for Recry-Beta-3, the external surface area S of Recry-Beta molecular sieves increased. external and the volume of the deposited pores V meso The increase indicates that the molecular sieve particle size has further decreased.

[0128] Preparation Example 6

[0129] This preparation example illustrates the preparation method of the beta molecular sieve (denoted as Recry-Beta molecular sieve) described in this invention.

[0130] The Recry-Beta molecular sieve was prepared according to the method described in Preparation Example 3, except that the molar ratio of the template agent to the Si-Beta molecular sieve was 0.18, and the resulting sample was designated as Recry-Beta molecular sieve-4.

[0131] Comparative Preparation Example 1

[0132] This comparative preparation example illustrates the preparation method of the comparative beta molecular sieve.

[0133] The process was carried out according to the methods described in Preparation Examples 2 and 3, except that the H-beta molecular sieve used was purchased from Qilu Catalyst Company and had a particle size greater than 100 nm, thus preparing molecular sieve D1.

[0134] Comparative Preparation Example 2

[0135] This comparative preparation example illustrates the preparation method of the comparative beta molecular sieve.

[0136] Si-beta molecular sieves were prepared according to a literature method (Miguel A. Camblor, Avelino Corma and Susana Valencia, Spontaneous nucleation and growth of pure silica zeolite-Betafree of connectivity defects, Chem. Cornmun., 1996, 2365-2366). The preparation method for the Si-beta molecular sieves was as follows: 43.62 g of tetraethylammonium hydroxide (35% aqueous solution, Aldrich) and 6.21 g of deionized water were mixed in a plastic container. Tetraethyl orthosilicate (Merck) was added, and the mixture was stirred at 25°C for 6.5 hours. 4.32 g of HF (48% aqueous solution) was added to form a white solid. The mixture was transferred to a stainless steel pressure vessel lined with polytetrafluoroethylene and crystallized at 150°C for 39 hours. The raw material composition was 0.54Et4OH:0.54HF:SiO2:7.25H2O. After crystallization, the molecular sieve was obtained by filtration and washing, with a crystallinity of 110% and a particle size of 0.5-5μm, thus obtaining molecular sieve D2.

[0137] Comparative preparation example 3

[0138] This comparative preparation example illustrates the preparation method of the comparative beta molecular sieve.

[0139] Recry-Beta molecular sieves were prepared according to the method described in Preparation Example 3, except that the molar ratio of the template agent to Si-Beta molecular sieves was 0.05, resulting in molecular sieve D3.

[0140] Example 1

[0141] This embodiment illustrates the preparation method of the catalyst described in this invention.

[0142] 4.0 g of Recry-Beta molecular sieve-1 synthesized in Preparation Example 3 was mixed with 120 mL of an aqueous solution containing 0.174 g of ZrO(NO3)2·2H2O (Acros Organic, 99.99%) at room temperature. The pH was adjusted to 8 with ammonia. After stirring continuously for 6 hours, the suspension was dried in air at 100 °C until all water evaporated. Finally, it was calcined in flowing air at 550 °C for 5 hours to obtain catalyst 1. In catalyst 1, the content of Beta molecular sieve was 97.9%, and the content of zirconium dioxide was 1.47 wt%.

[0143] Its XRD pattern is as follows Figure 8 As shown, the crystallinity of the catalyst is 60.9%. 29Si MAS NMR image as follows Figure 9 As shown, the UV-Vis diagram is as follows: Figure 10 As shown in the figure, the XPS graph is as follows Figure 11 As shown in the figure, most of the metals enter the molecular sieve framework and form bonds with the framework elements.

[0144] The total specific surface area of ​​the catalyst was determined to be S. BET =623m 2 / g, total pore volume V 总 =0.627cm 3 / g, packing pore volume V meso =0.428cm 3 / g.

[0145] Examples 2-4

[0146] This embodiment illustrates the preparation method of the catalyst described in this invention.

[0147] Following the method described in Example 1, Recry-Beta molecular sieves 2-4 prepared in Preparation Examples 4-6 were used to replace Recry-Beta molecular sieve-1 prepared in Preparation Example 3 to prepare catalysts 2-4.

[0148] Comparative Example 1

[0149] This comparative example is used to illustrate the preparation of the catalyst for comparison.

[0150] 4.0 g of the Si-Beta molecular sieve synthesized in Preparation Example 2 was mixed with 120 mL of an aqueous solution containing 0.174 g of ZrO(NO3)2·2H2O (Acros Organic, 99.99%) at room temperature. The pH was adjusted to 8 with ammonia. After stirring continuously for 6 hours, the suspension was dried in air at 100°C until all the water evaporated. Finally, it was calcined in flowing air at 550°C for 5 hours to obtain catalyst D1. The catalyst D1 contained 98.1% Beta molecular sieve and 0.89 wt% zirconium dioxide.

[0151] The XRD pattern of the sample is as follows Figure 8 As shown, the crystallinity is 51.7%. 29 Si MAS NMR image as follows Figure 9 As shown, the UV-Vis diagram is as follows: Figure 10 As shown in the figure, the XPS graph is as follows Figure 11 As shown in the figure, a small amount of metal enters the molecular sieve framework and forms bonds with the framework elements.

[0152] The BET specific surface area of ​​the catalyst was determined to be S. BET =529m 2 / g, total pore volume is V 总 =0.540cm 3 / g, packing pore volume is V 堆积 =0.365cm 3 / g.

[0153] Comparative Example 2

[0154] This comparative example is used to illustrate the preparation of the catalyst for comparison.

[0155] 2.0 g of Recry-Beta molecular sieve-1 synthesized in Preparation Example 3 was reacted with a solution containing 3.3 × 10⁻⁶ molecules at 40 °C. -3 A 100 mL ethanol solution of mol / L Zn(NO3)2 (Sinopharm Chemical Reagent Co., Ltd., 99.0%) was mixed and stirred continuously for 3 hours. The suspension (pH = 6.8) was then evaporated in a rotary distillation apparatus until the ethanol was completely evaporated. The resulting solid was washed three times with distilled water and dried in air at 80°C for 24 hours, and finally calcined in flowing air at 450°C for 3 hours to obtain catalyst D3. Catalyst D3 contained 98.1 wt% Beta-structured molecular sieve and 1.12 wt% zinc oxide.

[0156] The Zn-Beta-Recry molecular sieve has a crystallinity of 62.9% and a BET specific surface area of ​​S. BET =602m 2 / g, total pore volume is V 总 =0.593cm 3 / g, packing pore volume is V 堆积 =0.408cm 3 / g.

[0157] Comparative Example 3

[0158] This comparative example is used to illustrate the preparation of the catalyst for comparison.

[0159] 2.0 g of Recry-Beta molecular sieve-1 synthesized in Preparation Example 3 was reacted with a solution containing 1.5 × 10⁻⁶ molecules at 40 °C. -3A 100 mL isopropanol solution of mol / L Ta(OC2H5)5 (Acros Organic, 99.99%) was mixed and stirred continuously for 3 hours. The suspension (pH = 6.8) was then evaporated in a rotary distillation apparatus until the isopropanol was completely evaporated. The resulting solid was washed three times with distilled water and dried in air at 80°C for 24 hours, and finally calcined in flowing air at 450°C for 3 hours to obtain catalyst D4. Catalyst D4 contains 97.5 wt% Beta-structured molecular sieve and 1.36 wt% tantalum oxide. The crystallinity of the Ta-Beta-Recry molecular sieve is 60.5%, and the BET specific surface area is S0.05. BET =594m 2 / g, total pore volume is V 总 =0.586cm 3 / g, packing pore volume is V 堆积 =0.413cm 3 / g.

[0160] Comparative Examples 4-6

[0161] This comparative example is used to illustrate the preparation of the catalyst for comparison.

[0162] The method described in Example 1 was followed, except that the molecular sieves prepared in Comparative Preparation Examples 1-3 were used instead of the molecular sieves prepared in Preparation Example 3 to prepare catalysts D4-D6.

[0163] Test Example 1

[0164] The process of preparing 1,3-butadiene from ethanol was carried out using a fixed-bed reactor. The reactor was a stainless steel tubular isothermal reactor with an inner diameter of 12 mm and a catalyst loading of 4 g. Ethanol and acetaldehyde (40 wt% aqueous solution of acetaldehyde) were introduced from the top of the reactor. Material balance was performed on the apparatus, and the liquid recovery was over 95%.

[0165] The evaluation conditions were: based on a mixture of ethanol and acetaldehyde as reactants, and a gas hourly space velocity of 2 h⁻¹. -1 Carrier gas flow rate: 450 ml / min, reaction temperature: 350℃, reaction pressure: 0.44 MPa, catalyst loading: 2.0 g. Ethanol and acetaldehyde solution were used as raw materials, with an ethanol:acetaldehyde ratio of 2:1 (molar ratio).

[0166] For ease of expression, the following substances are abbreviated as: ethanol (EtOH), acetaldehyde (AA), unreacted ethanol (unreacted-EtOH), and unreacted acetaldehyde (unreacted-AA).

[0167] Ethanol conversion and 1,3-butadiene selectivity are calculated using the following formulas:

[0168]

[0169]

[0170] Where n is the mass percentage of each component in the product, and i is butadiene or other components in the product.

[0171] The catalysts prepared by the examples and comparative examples were applied to the reaction of ethanol-acetaldehyde to prepare 1,3-butadiene. The catalytic performance results are shown in Table 3 (sampling results at a reaction time of 2 h).

[0172] Table 3

[0173]

[0174]

[0175] As shown in Table 3, the Zr catalyst prepared using the Beta molecular sieve of this invention exhibits higher ethanol-acetaldehyde conversion and significantly better butadiene selectivity and yield compared to the comparative example when applied to the reaction of ethanol to 1,3-butadiene. This demonstrates that the catalyst provided by this invention possesses excellent catalytic performance.

[0176] from Figure 10 The results show that, compared with Comparative Example 1, most of the metals in the catalyst prepared in Example 1 entered the molecular sieve framework and formed bonds with the framework elements, which improved the activity and selectivity of the catalyst and effectively extended the stable operating time (it could run continuously for at least 60 hours when the ethanol-acetaldehyde conversion rate was above 40% and the butadiene selectivity was ≥65%). The catalyst prepared in Comparative Example 1 could only run continuously for less than 20 hours when the butadiene yield was ≥25%, and the repeatability was poor; the catalyst prepared in Comparative Example 4 had an operating time of less than 25 hours and a rapid decay.

[0177] Following the method described above, the catalyst 1 described in Example 1 of the present invention was used to prepare 1,3-butadiene under an alcohol-aldehyde ratio of 3:1. The results showed that the ethanol-acetaldehyde conversion rate was above 60%, and the butadiene selectivity was ≥40%, with continuous operation for at least 130 hours.

[0178] 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. A method for preparing a catalyst, characterized in that, The method includes: loading Zr onto a Recry-Beta molecular sieve, followed by drying and calcination to obtain the catalyst; The preparation method of the Recry-Beta molecular sieve includes: (1) H-Beta molecular sieve was acid-washed and dealuminized to obtain Si-Beta molecular sieve; (2) Si-Beta molecular sieve, template agent and water are mixed and then crystallized to obtain the Recry-Beta molecular sieve; The particle size of the H-Beta molecular sieve is below 90 nm. The molar ratio of the template agent to the Si-Beta molecular sieve (calculated as SiO2) is 0.08-0.

25.

2. The method according to claim 1, wherein, The loading methods include: impregnating Recry-Beta molecular sieves with a Zr precursor solution; and / or The amounts of each component are such that, based on the total weight of the catalyst, the content of Recry-Beta molecular sieve is 95-99.9 wt%, the content of zirconium-containing species (calculated as Zr oxides) is 0.1-5 wt%; and / or The impregnation conditions include: pH 3-12; temperature 20-60℃; and / or The roasting conditions include a temperature of 400-600℃ and a time of 1-6 hours.

3. The method according to claim 2, wherein, The amounts of each component are such that, based on the total weight of the catalyst, the content of Recry-Beta molecular sieve is 97-99.5 wt%, and the content of zirconium-containing species, calculated as Zr oxide, is 0.5-3 wt%. and / or The impregnation conditions include: pH 7-11; temperature 20-60℃.

4. The method according to claim 1, wherein, The H-Beta molecular sieve has a particle size of 20-50 nm.

5. The method according to claim 1, wherein, The acid leaching and dealuminization conditions ensure that the silica content in the obtained Si-Beta molecular sieve is above 99.5 wt%; and / or Wherein, the crystallinity of the Si-Beta molecular sieve is 60-90%; and / or Among them, the BET specific surface area of ​​the Si-Beta molecular sieve S BET 450-680 m 2 / g; and / or Wherein, the total pore volume of the Si-Beta molecular sieve V 总 It is 0.25-0.85 cm. 3 / g; and / or Wherein, the packing pore volume V of the Si-Beta molecular sieve meso It is 0.2-0.55 cm. 3 / g.

6. The method according to claim 5, wherein, The Si-Beta molecular sieve has a crystallinity of 70-85%; and / or Among them, the BET specific surface area of ​​the Si-Beta molecular sieve S BET 480-650m 2 / g; and / or Wherein, the total pore volume of the Si-Beta molecular sieve V 总 It is 0.45-0.7cm 3 / g; and / or Wherein, the packing pore volume V of the Si-Beta molecular sieve meso The value is 0.26-0.48cm. 3 / g.

7. The method according to claim 1, wherein, The template agent has at least one of the structures shown in formula (1): Equation (1); Among them, R1, R2, R3, and R4 are each independently selected from alkyl groups having 1-4 carbon atoms, X - This includes hydroxide ions or halide anions.

8. The method according to claim 7, wherein, R1, R2, R3, and R4 are each independently selected from one or more of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert-butyl; and / or Wherein, the template agent is tetramethylammonium hydroxide and / or tetraethylammonium hydroxide; and / or The molar ratio of the template agent to the Si-Beta molecular sieve (based on SiO2) is 0.1-0.2; and / or The molar ratio of water to Si-Beta molecular sieve (calculated as SiO2) is 3-10.

9. The method according to claim 8, wherein, R1, R2, R3, and R4 are each independently selected from methyl or ethyl; and / or The molar ratio of water to Si-Beta molecular sieve (calculated as SiO2) is 5-8.

10. The method according to claim 1, wherein, The crystallization conditions include: a crystallization temperature of 100-300℃ and a crystallization time of 12-120h.

11. The method according to claim 10, wherein, The crystallization conditions include: a crystallization temperature of 110-150℃ and a crystallization time of 24-72h.

12. The method according to claim 10, wherein, The method further includes calcining the crystallized product to obtain the Recry-Beta molecular sieve.

13. The method according to claim 12, wherein, The calcination conditions include: a calcination temperature of 400-650℃ and a calcination time of 2-8 hours.

14. The method according to claim 13, wherein, The calcination conditions include: a calcination temperature of 500-600℃ and a calcination time of 3-5 hours.

15. The method according to claim 1, wherein, The Recry-Beta molecular sieve has a silica-to-alumina ratio of 800 or higher; and / or Wherein, the crystallinity of the Recry-Beta molecular sieve is 50-100%; and / or Among them, the BET specific surface area of ​​the Recry-Beta molecular sieve S BET 450-680 m 2 / g; and / or The total pore volume of the Recry-Beta molecular sieve. V 总 The value is 0.25-0.85cm. 3 / g; and / or Wherein, the packing pore volume V of the Recry-Beta molecular sieve meso It is 0.2-0.55cm 3 / g.

16. The method of claim 15, wherein, The Recry-Beta molecular sieve has a silica-to-alumina ratio of 1200-2500; and / or Wherein, the crystallinity of the Recry-Beta molecular sieve is 55-80%; and / or Among them, the BET specific surface area of ​​the Recry-Beta molecular sieve S BET 500-660m 2 / g; and / or The total pore volume of the Recry-Beta molecular sieve. V 总 It is 0.45-0.7cm 3 / g; and / or Wherein, the packing pore volume V of the Recry-Beta molecular sieve meso The value is 0.26-0.48cm. 3 / g.

17. A catalyst, characterized in that, The catalyst comprises the Recry-Beta molecular sieve as described in any one of claims 1-16 and a zirconium-containing species supported on the Recry-Beta molecular sieve.

18. The catalyst according to claim 17, wherein, Based on the total weight of the catalyst, the content of Recry-Beta molecular sieve is 95-99.9 wt%; the content of zirconium-containing species, calculated as Zr oxide, is 0.1-5 wt%.

19. The catalyst according to claim 18, wherein, Based on the total weight of the catalyst, the Recry-Beta molecular sieve content is 97-99.5 wt%, and the zirconium-containing species content, calculated as Zr oxide, is 0.5-3 wt%.

20. The catalyst according to claim 18, wherein, The catalyst has a crystallinity of 30-85%; and / or The catalyst has a silicon-to-aluminum ratio of 800 or higher; and / or The catalyst's BET specific surface area S BET 450-680 m 2 / g; and / or The total pore volume of the catalyst V 总 It is 0.35-0.7 cm. 3 / g; and / or The packing pore volume V of the catalyst meso It is 0.1-0.7 cm. 3 / g.

21. The catalyst according to claim 20, wherein, The catalyst has a crystallinity of 40-75%; and / or The catalyst has a silicon-to-aluminum ratio of 1200-2500; and / or The catalyst's BET specific surface area S BET 480-650m 2 / g; and / or The total pore volume of the catalyst V 总 It is 0.44-0.65cm 3 / g; and / or The packing pore volume V of the catalyst meso It is 0.2-0.55cm 3 / g.

22. The use of the catalyst according to any one of claims 17-21 in hydrocarbon conversion reactions.

23. The application according to claim 22, wherein, The application is in the reaction of preparing 1,3-butadiene from ethanol and acetaldehyde.

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