High-acidity hierarchical porous Beta molecular sieves and their application in the catalytic dehydration of glucose to prepare 5-hydroxymethylfurfural

Abstract

This invention belongs to the field of Beta molecular sieve technology, and discloses a high-acidity hierarchical porous Beta molecular sieve and its application in the catalytic dehydration of glucose to prepare 5-hydroxymethylfurfural. The invention involves a first treatment of the microporous Beta molecular sieve with an inorganic base NaOH solution to obtain an intermediate product molecular sieve; a second treatment of the intermediate product molecular sieve with an aluminum salt and an organic base pyridine solution; and calcination of the second-treated molecular sieve with NH4Cl solution to generate a high-acidity hierarchical porous Beta molecular sieve. The molecular sieve provided by this invention has an increased Al content, forming more Si-O(H2O)... + )-Al structure, protic acid (H + With the increase of ) content, a high acid content hierarchical porous Beta molecular sieve was finally obtained, which can be used to catalyze the preparation of 5-HMF from glucose. The yield of 5-HMF is high, and there are few by-products such as humic substances. The catalyst can be reused.

Description

Technical Field

[0001] This invention belongs to the field of Beta molecular sieve technology, and specifically relates to high acidity hierarchical porous Beta molecular sieves and their application in the catalytic dehydration of glucose to prepare 5-hydroxymethylfurfural. Background Technology

[0002] 5-Hydroxymethylfurfural (5-HMF) is a common intermediate and important raw material for fine chemicals in biorefining processes. It can be upgraded through reactions such as oxidation, reduction, rehydration, and etherification to produce high-value-added chemicals and advanced fuels, including 2,5-furandicarboxylic acid (FDCA), 2,5-dimethylfuran (DMF), and γ-valerol (GVL). The production of 5-HMF from glucose via acid catalysis is simple in process and equipment, low in cost, produces few byproducts such as humic substances, and is easy to process, showing promising application prospects.

[0003] In related studies, catalysts used for the catalytic preparation of 5-HMF from glucose include ionic liquids, ion exchange resins, and molecular sieves. Ionic liquids and ion exchange resins face problems such as poor reusability and the generation of byproducts. Microporous Beta molecular sieves are commonly used catalysts in acid catalysis, and their regular pore structure and excellent acid properties have led to their widespread application in industrial production. However, the microporous channels limit the diffusion ability of Beta molecular sieves in macromolecular catalytic reactions, resulting in technical problems such as low product yield, high catalyst coking rate, short lifespan, and poor regeneration performance.

[0004] The kinetic diameter of a glucose molecule is about 1 nm, which is larger than the pore size of a Beta zeolite of 0.74 nm. If a microporous Beta zeolite is to be used as a catalyst to catalyze the preparation of 5-HMF from glucose, then mesoporous channels are needed to improve the catalytic efficiency of the Beta zeolite. Imparting a hierarchical porous structure to the zeolite can solve this problem. Hierarchical porous zeolites not only have the strong acidity, good hydrothermal stability and excellent shape selectivity of microporous zeolites, but also have the excellent mass transfer and diffusion performance of mesoporous channels.

[0005] While traditional alkaline etching methods are often used to impart hierarchical porous structures to molecular sieves, these methods introduce mesopores and cause the loss of related acidic centers, reducing the accessibility of glucose active sites within the Beta molecular sieve channels and hindering the reaction. Therefore, providing a high-acidity hierarchical porous Beta molecular sieve is of great significance for the preparation of 5-hydroxymethylfurfural from glucose. Summary of the Invention

[0006] To address the technical problem that the traditional alkaline etching method introduces mesopores but causes the loss of related acid centers, reducing the accessibility of active sites of glucose within the Beta molecular sieve channels, this invention provides a high-acidity hierarchical porous Beta molecular sieve.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A high-acidity hierarchical porous Beta molecular sieve is prepared by first treating the microporous Beta molecular sieve with an inorganic base NaOH solution to obtain an intermediate product molecular sieve; then treating the intermediate product molecular sieve with an aluminum salt and an organic base pyridine solution; and finally calcining the molecular sieve after the second treatment with NH4Cl solution to generate a high-acidity hierarchical porous Beta molecular sieve.

[0009] Furthermore, the molar ratio of silicon to aluminum in the microporous Beta molecular sieve is 10-300:1. The silicon-to-aluminum ratio (S / A ratio) is an important indicator of the structural characteristics of a molecular sieve. A higher S / A ratio indicates a smaller pore size and lower acid content, while a lower S / A ratio indicates a larger pore size and higher acid content. Therefore, using microporous Beta molecular sieves as catalysts in catalytic reactions presents technical problems such as low product yield, high catalyst coking rate, short lifespan, and poor regeneration performance due to the limited diffusion capacity of the microporous channels in macromolecular catalytic reactions. To solve these problems, mesoporous channels are inevitably needed to improve the catalytic efficiency of Beta molecular sieves, giving them a hierarchical porous structure. While traditional alkaline etching methods are often used to impart a hierarchical porous structure, the introduction of alkali causes the loss of related acidic centers, reducing the accessibility of reactants to active sites within the pores of the Beta molecular sieve, which is detrimental to the reaction. Therefore, the present invention uses an organic base pyridine solution and aluminum salt to re-treat the intermediate molecular sieve with crystal defects to solve the above-mentioned technical problems.

[0010] Furthermore, the aluminum salt described in this invention is one or more of sodium aluminate, aluminum nitrate, aluminum silicate, or aluminum chloride.

[0011] The preferred method for the first treatment of microporous Beta molecular sieves using inorganic alkali NaOH solution is as follows: the microporous Beta molecular sieves are mixed with inorganic alkali NaOH solution, stirred at 60-90℃ for 0.5-3.0h and dried at 80-150℃ for 6-24h to obtain the intermediate product molecular sieve.

[0012] Furthermore, the mass ratio of the microporous Beta molecular sieve to the NaOH solution is 1:10-1:40.

[0013] The preferred method for the second treatment of the intermediate molecular sieve in this invention is as follows: the intermediate molecular sieve is mixed with aluminum salt and organic base pyridine solution, stirred at 60-90℃ for 0.5-4h and dried at 80-150℃ for 6-12h; the dried molecular sieve is mixed with NH4Cl solution, stirred at 60-90℃ for 2-4h and dried at 80-150℃ for 6-12h, and finally calcined at 500-550℃ for 2-6h to obtain the high acid content hierarchical porous Beta molecular sieve product.

[0014] Furthermore, the mass ratio of the aluminum salt to the intermediate product molecular sieve is 1:10-1:40, the mass ratio of the intermediate product molecular sieve to the pyridine solution is 1:20, and the mass ratio of the dried molecular sieve to the NH4Cl solution is 1:40.

[0015] Finally, this invention also provides a method for preparing 5-hydroxymethylfurfural by dehydrating glucose, which involves using the high-acidity hierarchical porous Beta molecular sieve obtained above as a catalyst in an organic solvent solution to catalyze the dehydration of glucose to generate 5-hydroxymethylfurfural.

[0016] Furthermore, the mass ratio of the high-acidity hierarchical porous Beta molecular sieve to glucose is 1:3-1:10.

[0017] Furthermore, the reaction conditions are as follows: reaction temperature is 130-180℃, and reaction time is 10-60 min.

[0018] This invention provides a high-acidity hierarchical porous Beta molecular sieve and its application in the catalytic dehydration of glucose to prepare 5-hydroxymethylfurfural. The invention employs an inorganic base NaOH solution to first treat the microporous Beta molecular sieve to obtain an intermediate product molecular sieve; then, an aluminum salt and an organic base pyridine solution are used to second treat the intermediate product molecular sieve to finally obtain the high-acidity hierarchical porous Beta molecular sieve. Compared with related technologies, the technical solution of this invention has the following technical advantages:

[0019] This invention first treats a microporous molecular sieve with NaOH solution, etching the microporous structure of the sieve to form mesoporous channels. Simultaneously, some Si and Al are removed from the molecular sieve framework, forming crystal defects on the sieve surface. The intermediate product molecular sieve with crystal defects is then treated with an organic base pyridine solution and aluminum salt. The pyridine organic base interacts with the added aluminum source, "carrying" some aluminum back into the defect positions of the intermediate product molecular sieve. Although some mesoporous pore volume is sacrificed, the Al content in the molecular sieve increases, forming more Si-O(H₂)₂. + )-Al structure, protonic acid (H + By increasing the content of ) content, a high-acid, multi-level porous Beta molecular sieve was finally obtained.

[0020] The high-acidity hierarchical Beta molecular sieve obtained by the microporous molecular sieve treatment method provided by this invention can be used to catalyze the preparation of 5-HMF from glucose. Using this catalyst to prepare 5-HMF results in a high yield of 5-HMF, with fewer byproducts such as humic substances, less catalyst coke deposition, a long service life, and reusability. Attached Figure Description

[0021] Figure 1 X-ray diffraction scans of molecular sieves S1 and S2, the intermediate products of Example 1.

[0022] Figure 2 The N2 adsorption-desorption curve (A), BJH pore size distribution curve (B), Py-FTIR curve (C), and NH3-TPD curve (D) of the intermediate molecular sieves S1 and S2 in Example 1 are shown in Figure 1.

[0023] Figure 3 X-ray diffraction scans of molecular sieves S2 and S3 in Example 1;

[0024] Figure 4 The attached graphs (A), (B), Py-FTIR, (C), and NH3-TPD are for the N2 adsorption and desorption of molecular sieves S2 and S3 in Example 1.

[0025] Figure 5 X-ray diffraction scans of molecular sieves S2 and S4 in Example 1;

[0026] Figure 6 The attached graphs (A), (B), (C), and (D) show the N2 adsorption and desorption of molecular sieves S2 and S4 in Example 1. Detailed Implementation

[0027] This invention discloses a high-acidity hierarchical porous Beta molecular sieve and its application in the catalytic dehydration of glucose to prepare 5-hydroxymethylfurfural. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It is particularly important to note that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0028] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments.

[0029] Example 1: Preparation and parameter analysis of different molecular sieves

[0030] The intermediate product molecular sieve S1 was obtained by mixing a microporous Beta molecular sieve with a Si to Al molar ratio of 25 and a 0.4 mol / L NaOH solution, wherein the mass ratio of the microporous molecular sieve to the NaOH solution was 1:20. The mixture was stirred at 70 °C for 1.5 h, cooled, filtered, washed with deionized water until neutral, and dried at 100 °C for 12 h.

[0031] Molecular sieve S2 was obtained by treating the intermediate molecular sieve S1 obtained in this example with a 1 mol / L pyridine solution at 70 °C for 11 h. The mass ratio of the intermediate molecular sieve S1 to the pyridine solution was 1:20. After cooling, the mixture was filtered, washed with deionized water until neutral, and dried at 100 °C for 12 h. Then, the dried molecular sieve was mixed with a 1 mol / L NH4Cl solution at a mass ratio of 1:40. The mixture was stirred at 80 °C for 4 h, washed with deionized water 5 times, dried at 100 °C for 12 h, and calcined at 550 °C for 6 h to obtain molecular sieve S2.

[0032] Molecular sieve S3 was prepared by treating a microporous Beta molecular sieve with a Si to Al molar ratio of 25 (Si:Al) with a 1 mol / L pyridine solution at 70 °C for 1 h (mass ratio of microporous molecular sieve to pyridine solution 1:20). After cooling, the mixture was filtered, washed with deionized water until neutral, and dried at 100 °C for 12 h. The pyridine-treated molecular sieve was then mixed with NaOH solution (mass ratio of treated molecular sieve to NaOH solution 1:20), stirred at 70 °C for 1.5 h, cooled, filtered, washed with deionized water until neutral, and dried at 100 °C for 12 h. The dried molecular sieve was then mixed with a 1 mol / L NH4Cl solution (mass ratio of dried molecular sieve to NH4Cl solution 1:40), stirred at 80 °C for 4 h, washed five times with deionized water, dried at 100 °C for 12 h, and calcined at 550 °C for 6 h to obtain molecular sieve S3.

[0033] The difference between the preparation methods of molecular sieve S3 and molecular sieve S2 lies in the change of the treatment order of pyridine solution and NaOH solution on microporous Beta molecular sieve.

[0034] Molecular sieve S4 was prepared by mixing the intermediate molecular sieve S1 obtained in this embodiment with sodium aluminate and treating it with a 1 mol / L pyridine solution at 70°C for 1 h. The mass ratio of intermediate molecular sieve S1 to pyridine solution was 1:20, and the mass ratio of sodium aluminate to intermediate molecular sieve S1 was 1:20. After cooling, the mixture was filtered, washed with deionized water until neutral, and dried at 100°C for 12 h. Then, the dried molecular sieve was mixed with a 1 mol / L NH4Cl solution at a mass ratio of 1:40. The mixture was stirred at 80°C for 4 h, washed with deionized water 5 times, dried at 100°C for 12 h, and calcined at 550°C for 6 h to finally obtain the target product of this invention, high acid content hierarchical porous Beta molecular sieve S4.

[0035] The difference between molecular sieve S4 and molecular sieve S2 in their preparation methods is that molecular sieve S4 has sodium aluminate, an aluminum source, added during the second pyridine treatment.

[0036] The intermediate products molecular sieves S1, S2, and S3 prepared in this example, as well as the target product of this invention, high-acidity hierarchical porous Beta molecular sieve S4, were analyzed. The analysis results are as follows:

[0037] 1.1 X-ray diffraction scans were performed on the intermediate products molecular sieves S1 and S2. The X-ray diffraction patterns are shown in the figure. Figure 1 ; Figure 2 The N2 adsorption-desorption curves (A), BJH pore size distribution curves (B), Py-FTIR curves (C), and NH3-TPD curves (D) for intermediate products molecular sieves S1 and S2 are shown in Table 1. The parameters of intermediate products molecular sieves S1 and S2 are also shown in Table 1.

[0038] Table 1 Structural parameters of molecular sieves S1 and S2

[0039]

[0040]

[0041] Note: The calculation of relative crystallinity a uses the Beta molecular sieve parent material as 100%.

[0042] Table 1 shows that molecular sieve S2 and the intermediate product molecular sieve S1 have similar relative crystallinity and pore structure. However, the total acidity of molecular sieve S2 is 1.6, which is higher than that of S1 (1.3). Furthermore, NH3-TPD analysis indicates that the acid strength of molecular sieve S2 is greater than that of S1. Py-FTIR analysis indicates that molecular sieve S2... The acid to Lewis ratio is 1.2, which is greater than the 1.0 ratio of the intermediate molecular sieve S1. This is because pyridine treatment "encapsulates" some Al atoms, which are then inserted into defects in the molecular sieve framework, forming Si-O(H)₂. +The )-OAl structure increases the proportion of protic acids. Therefore, the synergistic treatment of microporous molecular sieves with inorganic base NaOH and organic base pyridine is more effective in improving the acidity of the molecular sieves than the traditional inorganic base NaOH etching method.

[0043] 1.2 X-ray diffraction scans were performed on molecular sieves S2 and S3. The X-ray diffraction patterns are shown in the figure. Figure 3 ; Figure 4 The N2 adsorption-desorption curves (A), BJH pore size distribution curves (B), Py-FTIR curves (C), and NH3-TPD curves (D) for molecular sieves S2 and S3 are shown in Table 2. The parameters of molecular sieves S2 and S3 are also shown in Table 2.

[0044] Table 2 Structural parameters of molecular sieves S2 and S3

[0045]

[0046]

[0047] Note: The calculation of relative crystallinity a uses the Beta molecular sieve parent material as 100%.

[0048] Table 2 shows that the relative crystallinity of molecular sieve S3 and molecular sieve S2 is similar. Molecular sieve S3 has more microporous structures etched to form mesoporous channels, and its average pore size... Greater than S2 Therefore, pyridine treatment before NaOH etching produces a more significant etching effect on the pores of the molecular sieve. The total acid content of molecular sieve S3 (1.4 mmNH3 / g) is lower than that of molecular sieve S2 (1.6 mmNH3 / g), and the acid distribution shows that the acid strength of molecular sieve S3 is also lower than that of molecular sieve S2. Therefore, NaOH etching after pyridine treatment can form larger mesoporous channels, but the acidity is weaker.

[0049] 1.3 X-ray diffraction scans were performed on molecular sieves S2 and S4. The X-ray diffraction patterns are shown in the figure. Figure 5 ; Figure 6 The N2 adsorption-desorption curves (A), BJH pore size distribution curves (B), Py-FTIR curves (C), and NH3-TPD curves (D) for molecular sieves S2 and S4 are shown in Table 3. The parameters of molecular sieves S2 and S4 are also shown in Table 3.

[0050] Table 3 Structural parameter data of molecular sieves S2 and S4

[0051]

[0052] Note: The calculation of relative crystallinity a uses the Beta molecular sieve parent material as 100%.

[0053] Table 3 shows that in the target product of this invention, the high-acidity hierarchical porous Beta molecular sieve S4, more Al atoms are inserted into the framework defects of the molecular sieve. The occupancy of Al atoms reduces the mesoporous channels. Therefore, the pore volume of molecular sieve S4 (0.483 mL / g) is smaller than that of molecular sieve S2 (0.632 mL / g), and the average pore size is also smaller. Below S2 The total acid content of molecular sieve S4 is comparable to that of molecular sieve S2, but The ratio of acid to Lewis acid in molecular sieve S4 is higher than that in molecular sieve S2, therefore molecular sieve S4 forms more Si-O(H)₂. + The structure is Si-OAl. Therefore, the processing method provided by this invention involves treating the microporous Beta molecular sieve sequentially with inorganic base NaOH and organic base pyridine, with an external aluminum source. This method, while sacrificing some mesopore volume, satisfies the porous nature of the Beta molecular sieve while simultaneously forming more Si-O(H)-Al structure. + The α-Al structure improves the molecular sieve's properties. Acidic.

[0054] Example 2: Preparation of high-acidity hierarchical porous Beta molecular sieve

[0055] Prepare a 0.6 mol / L NaOH solution, mix a microporous Beta molecular sieve with a Si to Al molar ratio of 100 with the above NaOH solution, the mass ratio of the microporous Beta molecular sieve to the above NaOH solution is 1:10, stir at 90℃ for 0.5 h, cool and filter, wash with deionized water until neutral, dry at 80℃ for 24 h to obtain the intermediate product molecular sieve;

[0056] Sodium aluminate and intermediate molecular sieve were mixed at a mass ratio of 1:40, and then added to a 1.2 mol / L pyridine solution. The mass ratio of the intermediate molecular sieve to the pyridine solution was 1:20. The mixture was stirred at 60 °C for 2 h, cooled, filtered, washed with deionized water until neutral, and dried at 150 °C for 6 h. The dried molecular sieve was mixed with a 1 mol / L NH4Cl solution at a mass ratio of 1:40. The mixture was stirred at 90 °C for 2 h, washed several times with deionized water, dried at 150 °C for 6 h, and calcined at 530 °C for 4 h to obtain the high-acidity hierarchical porous Beta molecular sieve product.

[0057] Example 3: Preparation of high-acidity hierarchical porous Beta molecular sieve

[0058] Prepare a 1 mol / L NaOH solution, mix a microporous Beta molecular sieve with a Si to Al molar ratio of 80 with the above NaOH solution, the mass ratio of microporous Beta molecular sieve to NaOH solution is 1:40, stir at 60℃ for 3 h, cool and filter, wash with deionized water until neutral, dry at 150℃ for 6 h to obtain the intermediate product molecular sieve.

[0059] Alumina silicate and intermediate molecular sieve were mixed at a mass ratio of 1:10, and then added to a 0.5 mol / L pyridine solution at a mass ratio of 1:20. The mixture was stirred at 90 °C for 4 h, cooled, filtered, washed with deionized water until neutral, and dried at 80 °C for 12 h. The dried molecular sieve was then mixed with a 1 mol / L NH4Cl solution at a mass ratio of 1:40. The mixture was stirred at 60 °C for 4 h, washed several times with deionized water, dried at 80 °C for 12 h, and calcined at 500 °C for 6 h to obtain the high-acidity hierarchical porous Beta molecular sieve product.

[0060] Example 4 Preparation of 5-hydroxymethylfurfural

[0061] 0.15 g of glucose and 0.03 g of Beta molecular sieve catalyst prepared in Example 2 were added to a high-pressure reactor lined with polytetrafluoroethylene. Then, 1.5 ml of deionized water and 3.5 ml of methyl isobutyl ketone (MIBK) were added, and the mixture was heated to 150 °C and maintained at this temperature for 30 min to produce 5-hydroxymethylfurfural (5-HMF). The glucose conversion rate was 97.2%, the 5-HMF yield was 84.7%, and the humic matter yield was 12.1%.

[0062] Comparative Example 1

[0063] 0.15 g of glucose and 0.03 g of microporous Beta molecular sieve catalyst (Si to Al molar ratio of 100) were added to a high-pressure reactor lined with polytetrafluoroethylene. Then, 1.5 ml of deionized water and 3.5 ml of methyl isobutyl ketone (MIBK) were added, and the mixture was heated to 150 °C and maintained at this temperature for 30 min to produce 5-hydroxymethylfurfural (5-HMF). The glucose conversion rate was 81.8%, the 5-HMF yield was 44.5%, and the humic matter yield was 32.9%.

[0064] In Comparative Example 1, an untreated microporous Beta molecular sieve was used. The molar ratio of silicon to aluminum in SiO2 and Al2O3 in the molecular sieve was 100:1. This sieve was used to catalyze the preparation of 5-hydroxymethylfurfural from glucose. This molecular sieve had a relatively dense structure and small pore size. Due to the microporous channels, the diffusion ability of the Beta molecular sieve in macromolecular catalytic reactions was limited, resulting in low product yield. It also led to technical problems such as high catalyst coking rate, short lifespan, and poor regeneration performance. Example 4 of this invention uses a high-acidity hierarchical porous Beta molecular sieve as a catalyst. The microporous Beta molecular sieve with a high silicon-to-aluminum ratio and small pore size was treated twice, resulting in a finished Beta molecular sieve with larger mesoporous channels and stronger acidic centers. The resulting catalyst had a lower coking rate and longer lifespan. When used to catalyze the preparation of 5-hydroxymethylfurfural from glucose, it showed better catalytic performance.

[0065] Example 5: Reuse of High Acidity Hierarchical Porous Beta Molecular Sieves

[0066] The high-acidity hierarchical porous Beta molecular sieve used in Example 4 was recovered and reused five times. The results of the reuse of the high-acidity hierarchical porous Beta molecular sieve catalyst are shown in Table 4.

[0067] Table 4. Results of Reuse of Beta-Py1 / 40

[0068]

[0069] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing 5-hydroxymethylfurfural by dehydration of glucose, characterized in that, In an organic solvent solution, a high-acidity hierarchical porous Beta molecular sieve was used as a catalyst to catalyze the dehydration of glucose to produce 5-hydroxymethylfurfural. The preparation method of the high-acidity hierarchical porous Beta molecular sieve includes the following steps: a first treatment of the microporous Beta molecular sieve with an inorganic alkali NaOH solution to obtain an intermediate product molecular sieve; a second treatment of the intermediate product molecular sieve with an aluminum salt and an organic alkali pyridine solution; and calcination of the second-treated molecular sieve with an NH4Cl solution to generate a high-acidity hierarchical porous Beta molecular sieve; wherein the conditions for the second treatment of the intermediate product molecular sieve are stirring at 60-90℃ for 0.5-4 h and drying at 80-150℃ for 6-12 h.

2. The method as described in claim 1, characterized in that, The molar ratio of Si to Al in the microporous Beta molecular sieve is 10-300:

1.

3. The method as described in claim 1, characterized in that, The aluminum salt is one or more of sodium aluminate, aluminum nitrate, or aluminum chloride.

4. The method as described in claim 1, characterized in that, The conditions for the first treatment of the microporous Beta molecular sieve with the inorganic base NaOH solution are: stirring at 60-90℃ for 0.5-3.0 h and drying at 80-150℃ for 6-24 h.

5. The method as described in claim 4, characterized in that, The mass ratio of the microporous Beta molecular sieve to the NaOH solution is 1:10-1:

40.

6. The method as described in claim 1, characterized in that, The dried molecular sieve is mixed with NH4Cl solution, stirred at 60-90℃ for 2-4 h and dried at 80-150℃ for 6-12 h, and finally calcined at 500-550℃ for 2-6 h to obtain the high acid content hierarchical porous Beta molecular sieve product.

7. The method as described in claim 6, characterized in that, The mass ratio of the aluminum salt to the intermediate product molecular sieve is 1:10-1:40, the mass ratio of the intermediate product molecular sieve to the pyridine solution is 1:20, and the mass ratio of the dried molecular sieve to the NH4Cl solution is 1:

40.

8. The method as described in claim 1, characterized in that, The mass ratio of the high-acidity hierarchical porous Beta molecular sieve to the glucose is 1:3-1:

10.

9. The method as described in claim 1 or 8, characterized in that, The catalytic reaction conditions are a reaction temperature of 130-180℃ and a reaction time of 10-60 min.

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