Use of a zirconium-based metal organic framework film material to catalyze acetal reactions

Abstract

The application relates to application of a zirconium-based metal organic framework film material to a fast high-conversion-rate catalytic acetal reaction. The catalyst used in the catalytic acetal reaction is a zirconium-based metal organic framework nanosheet which is regularly stacked under negative pressure to prepare a film catalytic material with one-dimensional channels perpendicular to a plane. Under the driving of a pressure difference, in a continuous flow phase reaction mode, efficient reaction of aldehyde molecules and alcohol molecules is carried out in the one-dimensional limited channels of the film catalytic material, the product flows out and is separated from the system, and finally, a fast and efficient acetal reaction is realized. Moreover, the conversion rate of the reactant aldehyde molecules is above 85%, and separation of the product from the catalytic material can be realized. The method is suitable for acetal reactions of different reaction activities and different sizes of reaction molecules.

Description

Technical Field

[0001] This invention belongs to the field of catalytic materials technology, and specifically relates to the application of a zirconium-based metal-organic framework membrane material for rapid and high-conversion catalytic acetal reaction. Background Technology

[0002] The acetal reaction is a process in which an alcohol molecule undergoes protonation and nucleophilic attack, leading to an addition reaction with an aldehyde molecule and ultimately producing an alcohol or ether compound. Acetal reactions are an important class of reactions with wide applications in organic synthesis, including drug synthesis, fine chemical preparation, functional material synthesis, industrial catalysis, and the synthesis of organic intermediates. To improve catalyst utilization efficiency and reduce product separation difficulty, heterogeneous catalysts, such as solid acids, acidic zeolites, and MOF powders, are commonly used in this type of reaction (Can. J. Chem. Eng. 1999, 77, 489; Adv. Synth. Catal. 2010, 352, 3022-3030). However, these reactions suffer from drawbacks such as long reaction times (>3 hours) and low conversion rates (60-80%) at room temperature. Furthermore, when using heterogeneous catalysts, the reaction requires centrifugation after completion, and the crude product needs further purification via silica gel column chromatography or preparative liquid chromatography, consuming significant amounts of reagents and time, and causing environmental pollution, which contradicts the principles of green chemistry. Therefore, finding a membrane catalytic material that can achieve rapid and high-conversion acetal reactions is of great significance. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides an application of zirconium-based metal-organic framework membrane materials in catalyzing acetal reactions and a catalytic method thereof.

[0004] The technical solution of the present invention is as follows:

[0005] Applications of zirconium-based metal-organic framework membrane materials in catalyzing acetal reactions of aldehyde and alcohol molecules.

[0006] According to an embodiment of the present invention, the thickness of the zirconium-based metal-organic framework membrane material is 0.5–100 μm, for example 1–80 μm, 1–70 μm, 1–60 μm, 1–50 μm, 2–40 μm or 5–30 μm; the interlayer spacing of the membrane material is 0.50–0.75 nm, for example 0.60–0.67 nm.

[0007] According to an embodiment of the present invention, the aldehyde molecule is an aliphatic aldehyde or an aromatic aldehyde, such as C 6-12 Aromatic aldehydes and their derivatives; for example, benzaldehyde, either unsubstituted or substituted with one, two or more of the following groups: halogen, C 1-6 Alkyl, C 1-6alkoxy or halogenated C 1-6 Alkyl; for example, the aldehyde molecule is selected from benzaldehyde, p-methylbenzaldehyde, p-anisaldehyde or 4-chlorobenzaldehyde.

[0008] According to an embodiment of the present invention, the alcohol molecule is an aliphatic alcohol or an aromatic alcohol compound, for example, a C1000011-C1 ... 1-12 Aliphatic alcohols, such as methanol, ethanol, n-propanol, isopropanol, tert-butanol, or 1-butanol; aromatic alcohols, such as benzyl alcohol or phenylethanol.

[0009] According to an embodiment of the present invention, the zirconium-based metal-organic framework membrane material is prepared by the following method:

[0010] 1,3,5-tris(4-carboxyphenyl)benzene, zirconium chloride, end-capping agent and reaction solvent were mixed and heated to react. After the reaction was completed, the mixture was centrifuged and dried under vacuum. The resulting product was dispersed in an aprotic solvent and subjected to ultrasonic treatment to obtain a zirconium-based metal-organic framework nanosheet dispersion.

[0011] Subsequently, the zirconium-based metal-organic framework nanosheet dispersion was vacuum filtered to form a membrane, and the obtained membrane was subjected to negative pressure drying and heat treatment to obtain the zirconium-based metal-organic framework membrane material.

[0012] According to an embodiment of the present invention, the thickness of the zirconium-based metal-organic framework nanosheet is 4.0–6.0 nm, for example, 4.4–5.6 nm.

[0013] According to an embodiment of the present invention, the capping agent is formic acid; the reaction solvent is DMF and water.

[0014] In some embodiments of the present invention, the zirconium-based metal-organic framework membrane material is prepared by the following method: 1,3,5-tris(4-carboxyphenyl)benzene, zirconium chloride, water, formic acid and DMF are mixed and reacted at 100-140°C for 0.5-12 hours. After the reaction is completed and cooled to room temperature, the reaction solution is centrifuged to obtain a centrifuged substrate. DMF is added to the centrifuged substrate, followed by ultrasonic treatment, centrifugation, and collection of the substrate. This process is repeated at least once. After washing, the substrate is vacuum dried, dispersed with DMF, and then ultrasonically treated to obtain a zirconium-based metal-organic framework nanosheet dispersion.

[0015] The obtained zirconium-based metal-organic framework nanosheet dispersion was vacuum filtered to form a membrane. The membrane was then subjected to negative pressure drying and heat treatment at 100-140℃ for 0.5-12 hours to obtain the membrane catalytic material.

[0016] The present invention also provides a method for catalyzing the acetal reaction of aldehyde molecules and alcohol molecules using the zirconium-based metal-organic framework membrane material as described above, comprising the following steps: passing a reaction solution containing aldehyde molecules and alcohol molecules through the zirconium-based metal-organic framework membrane material as described above to catalyze the reaction and obtain an acetal product.

[0017] According to an embodiment of the present invention, the molar ratio of the aldehyde molecule to the alcohol molecule is 1:1 to 1000, for example 1:2 to 500, 1:2 to 400, 1:2 to 300, 1:2 to 200 or 1:2 to 100; such as 1:2 to 75.

[0018] According to an embodiment of the present invention, the reaction is carried out under the action of a pressure difference, wherein the pressure difference is 0.1 atm or more, for example 0.9 atm or more, 0.8 atm or more, or 0.7 atm or more.

[0019] According to an embodiment of the present invention, the reaction temperature is above 0°C, for example above 10°C, such as 0 to 30°C.

[0020] According to an embodiment of the present invention, the method includes the following steps: preparing a membrane reaction solution by taking 1 mmol of reactant aldehyde molecules and 2-75 mmol of reactant alcohol molecules; passing the reaction solution through the zirconium-based metal-organic framework membrane material as described above under conditions of 0-30°C by pressure difference (above 0.9 atm); the reaction is carried out in a continuous flow phase reaction manner, and the reactant aldehyde molecules and alcohol molecules react in a one-dimensional confined channel within the thin film layer of the zirconium-based metal-organic framework membrane material.

[0021] According to an embodiment of the present invention, the reaction is carried out at atmospheric pressure in an air atmosphere.

[0022] In some embodiments of the present invention, the alcohol molecule serves simultaneously as a reactant and a solvent.

[0023] In some embodiments of the present invention, the product flows out with the alcohol molecules and is separated from the membrane material.

[0024] Beneficial effects

[0025] The catalyst used in this invention for the acetal reaction is a membrane catalytic material with one-dimensional channels perpendicular to the plane, formed by the regular stacking of zirconium-based metal-organic framework nanosheets under negative pressure. Driven by a pressure difference, aldehyde and alcohol molecules react efficiently within the one-dimensional confined channels of the membrane catalytic material in a continuous mobile phase reaction. The products flow out with the mobile phase and leave the system, ultimately achieving a rapid and efficient acetal reaction (reaction time less than 1 second). (The membrane material of this invention is relatively regularly stacked, belonging to an oriented stacking method, and the actual spacing between membrane layers is impenetrable to reactant molecules, constructing a one-dimensional confined channel within the membrane. The confinement effect of the one-dimensional channels within the membrane allows for the matching of frontier molecular orbitals of reactants with different reactivity and sizes, reducing the activation energy of the reaction, thereby enabling rapid acetal reactions of different aldehyde and alcohol molecules at room temperature.) Furthermore, the conversion rate of reactant aldehyde molecules is over 85%, and the products can be separated from the catalytic material without the need for product separation and purification. This method is applicable to acetal reactions of different reactivity and sizes of reactant molecules.

[0026] Specifically, the zirconium-based metal-organic framework membrane material of the present invention has the following advantages in catalyzing acetal reactions:

[0027] 1. The reaction proceeds at room temperature without heating.

[0028] 2. Short reaction time (<1 second).

[0029] 3. Applicable to acetal reactions of molecules with different reactivity and sizes.

[0030] 4. The reaction conversion rate can reach 100%, and the product does not require separation and purification.

[0031] 5. Continuous mobile phase reaction, eliminating the need to separate the catalyst and products. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a membrane catalysis process. Driven by a pressure difference, the reaction solution permeates through a zirconium-based metal-organic framework membrane material. Catalytic reactants A and B react within a one-dimensional confined channel inside the membrane, and the products flow out with the solvent, escaping the membrane system. The collected solution is quantitatively analyzed using 1H NMR spectroscopy to calculate the reaction conversion rate. Detailed Implementation

[0033] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0034] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0035] In the following examples, the conversion rate of the reactant aldehyde molecule was calculated using the following method:

[0036] Quantitative analysis of the membrane-collected liquid (i.e., the product) was performed using 1H NMR spectroscopy to calculate the reaction conversion rate. The quantitative analysis method for the collected liquid involved preparing an NMR sample using a deuterated reagent (DMSO) on a portion of the collected liquid. Characteristic hydrogen atoms were present in both the reactant aldehyde molecule and the product molecule. A correlation existed between the number of characteristic hydrogen atoms and their corresponding molecules. By comparing the integrated areas of single peaks at different chemical shifts through single-peak fitting, the ratio of the corresponding molecule numbers was calculated, and thus the conversion rate of the reactant aldehyde molecules was determined.

[0037] Example 1

[0038] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). Five mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane via vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and isopropanol (molar ratio of benzaldehyde to isopropanol in the reaction solution: 1:75, pressure difference: 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate of benzaldehyde was 100%. Specific procedures are as follows: Figure 1 As shown. By Figure 1 It can be seen that the product can be directly filtered into the conical flask without any other operation, thus achieving the separation of the product from the membrane catalyst and the raw material benzaldehyde.

[0039] Example 2

[0040] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). Five mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and n-propanol (molar ratio of benzaldehyde to n-propanol in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 99%.

[0041] Example 3

[0042] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). 5 mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and ethanol (molar ratio of benzaldehyde to ethanol in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 96%. Specific procedures are as follows: Figure 1 As shown.

[0043] Example 4

[0044] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). Five mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven and heat-treated at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and tert-butanol (molar ratio of benzaldehyde to tert-butanol in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 97.5%. The specific reaction procedure is as follows: Figure 1 As shown.

[0045] Example 5

[0046] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). Five mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven and heat-treated at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of anisaldehyde and isopropanol (molar ratio of the two in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 92.5%. The specific reaction procedure is as follows: Figure 1 As shown.

[0047] Example 6

[0048] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). Five mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven and heat-treated at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 38.1 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of p-tolualdehyde and isopropanol (molar ratio in the reaction solution: 1:75, pressure difference: 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 86.7%. The specific reaction procedure is as follows: Figure 1 As shown.

[0049] Example 7

[0050] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). 1 mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 7.6 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and isopropanol (molar ratio of the two substances in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 87%.

[0051] Example 8

[0052] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). 2 mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 15.2 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and isopropanol (molar ratio of benzaldehyde to isopropanol in the reaction solution: 1:75, pressure difference: 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 90%. Specific procedures are as follows: Figure 1 As shown.

[0053] Example 9

[0054] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). 3 mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 22.9 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and isopropanol (molar ratio of benzaldehyde to isopropanol in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 92.5%. Specific procedures are as follows: Figure 1 As shown.

[0055] Example 10

[0056] Take 30 mg of 1,3,5-tris(4-carboxyphenyl)benzene and 30 mg of zirconium chloride, add 2 mL of ultrapure water, 15 mL of N,N-dimethylformamide, and 2 mL of formic acid. Stir for 10 minutes to mix evenly, then heat to 120 °C and stir for 2 hours. After the reaction is complete and cooled to room temperature, centrifuge the reaction solution (10,000 rpm) to obtain the substrate. Add 20 mL of N,N-dimethylformamide to the substrate and treat with ultrasound at 150 W for 5 minutes, then centrifuge again (8,000 rpm) to collect the substrate. Repeat the cycle three times. After washing, vacuum dry for 24 hours, then treat with 20 mL of N,N-dimethylformamide with ultrasound at 150 W for 30 minutes to obtain a zirconium-based metal-organic framework nanosheet dispersion with a nanosheet thickness of approximately 4.4–5.6 nm. Store at room temperature in a sealed container (concentration approximately 0.8 mg / mL). 4 mL of zirconium-based metal-organic framework nanosheet dispersion was used to prepare a membrane using vacuum filtration (0.9 atm). After the water on top of the membrane was removed, the membrane was removed from the filtration apparatus and dried at room temperature in a petri dish for 3 hours. The membrane was then transferred to an oven for heat treatment at 120°C for 12 hours. Finally, the heat-treated membrane (approximately 30.5 μm thick, with an interlayer spacing of 0.65 nm) was used as a catalyst to catalyze the acetal reaction of benzaldehyde and isopropanol (molar ratio of benzaldehyde to isopropanol in the reaction solution was 1:75, pressure difference was 0.9 atm). The reaction temperature was 22°C, and the reaction time was less than 1 second. The product was tested, and the conversion rate was 96%. Specific procedures are as follows: Figure 1 As shown.

[0057] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. Application of zirconium-based metal-organic framework membrane materials in catalyzing acetal reactions of aldehyde and alcohol molecules; The zirconium-based metal-organic framework membrane material was prepared using the following method: 1,3,5-tris(4-carboxyphenyl)benzene, zirconium chloride, end-capping agent and reaction solvent were mixed and heated to react. After the reaction was completed, the mixture was separated by centrifugation and dried under vacuum. The resulting product was dispersed in an aprotic solvent and subjected to ultrasonic treatment to obtain a zirconium-based metal-organic framework nanosheet dispersion. Subsequently, the zirconium-based metal-organic framework nanosheet dispersion was vacuum filtered to form a membrane, and the obtained membrane was subjected to negative pressure drying and heat treatment to obtain the zirconium-based metal-organic framework membrane material. The capping agent is formic acid; The thickness of the zirconium-based metal-organic framework membrane material is 0.5~100μm; The interlayer spacing of the membrane material is 0.50~0.75 nm; The aldehyde molecule is an aliphatic aldehyde or an aromatic aldehyde; The alcohol molecule is an aliphatic alcohol or an aromatic alcohol compound.

2. The application according to claim 1, characterized in that, The thickness of the zirconium-based metal-organic framework membrane material is 1~80μm.

3. The application according to claim 1, characterized in that, The interlayer spacing of the membrane material is 0.60~0.67 nm.

4. The application according to claim 1, characterized in that, The aldehyde molecule is C. 6-12 Aromatic aldehydes and their derivatives.

5. The application according to claim 1, characterized in that, The aldehyde molecule is benzaldehyde that is unsubstituted or substituted with one, two or more of the following groups: halogen, C 1-6 Alkyl, C 1-6 alkoxy or halogenated C 1-6 alkyl.

6. The application according to claim 1, characterized in that, The aldehyde molecule is selected from benzaldehyde, p-methylbenzaldehyde, p-anisaldehyde, or 4-chlorobenzaldehyde.

7. The application according to claim 1, characterized in that, The alcohol molecule is C. 1-12 Aliphatic alcohols.

8. The application according to claim 1, characterized in that, The alcohol molecule is methanol, ethanol, n-propanol, isopropanol, tert-butanol, 1-butanol, benzyl alcohol, or phenylethanol.

9. The application according to any one of claims 1-8, characterized in that, The reaction solvents are DMF and water.

10. A method for catalyzing the acetal reaction of aldehyde and alcohol molecules using zirconium-based metal-organic framework membrane materials, characterized in that, The process includes the following steps: passing a reaction solution containing aldehyde and alcohol molecules through a zirconium-based metal-organic framework membrane material to catalyze the reaction and obtain an acetal product; The zirconium-based metal-organic framework membrane material was prepared using the following method: 1,3,5-tris(4-carboxyphenyl)benzene, zirconium chloride, end-capping agent and reaction solvent were mixed and heated to react. After the reaction was completed, the mixture was separated by centrifugation and dried under vacuum. The resulting product was dispersed in an aprotic solvent and subjected to ultrasonic treatment to obtain a zirconium-based metal-organic framework nanosheet dispersion. Subsequently, the zirconium-based metal-organic framework nanosheet dispersion was vacuum filtered to form a membrane, and the obtained membrane was subjected to negative pressure drying and heat treatment to obtain the zirconium-based metal-organic framework membrane material. The capping agent is formic acid; The thickness of the zirconium-based metal-organic framework membrane material is 0.5~100μm; The interlayer spacing of the membrane material is 0.50~0.75 nm; The aldehyde molecule is an aliphatic aldehyde or an aromatic aldehyde; The alcohol molecule is an aliphatic alcohol or an aromatic alcohol compound.

11. The method according to claim 10, characterized in that, The thickness of the zirconium-based metal-organic framework membrane material is 1~80μm.

12. The method according to claim 10, characterized in that, The interlayer spacing of the membrane material is 0.60~0.67 nm.

13. The method according to claim 10, characterized in that, The aldehyde molecule is C. 6-12 Aromatic aldehydes and their derivatives.

14. The method according to claim 10, characterized in that, The aldehyde molecule is benzaldehyde that is unsubstituted or substituted with one, two or more of the following groups: halogen, C 1-6 Alkyl, C 1-6 alkoxy or halogenated C 1-6 alkyl.

15. The method according to claim 10, characterized in that, The aldehyde molecule is selected from benzaldehyde, p-methylbenzaldehyde, p-anisaldehyde, or 4-chlorobenzaldehyde.

16. The method according to claim 10, characterized in that, The alcohol molecule is C. 1-12 Aliphatic alcohols.

17. The method according to claim 10, characterized in that, The alcohol molecule is methanol, ethanol, n-propanol, isopropanol, tert-butanol, 1-butanol, benzyl alcohol, or phenylethanol.

18. The method according to claim 10, characterized in that, The molar ratio of the aldehyde molecule to the alcohol molecule is 1:1 to 1000.

19. The method according to claim 10, characterized in that, The reaction is carried out under the action of a pressure difference greater than 0.1 atm.

20. The method according to claim 10, characterized in that, The reaction temperature is above 0℃.

21. The method according to claim 10, characterized in that, The method includes the following steps: preparing a membrane reaction solution by taking 1 mmol of reactant aldehyde molecules and 2-75 mmol of reactant alcohol molecules; passing the reaction solution through a zirconium-based metal-organic framework membrane material under conditions of 0-30°C by pressure difference; the reaction is carried out in a continuous flow phase reaction mode, and the reactant aldehyde molecules and alcohol molecules react in a one-dimensional confined channel within the thin film layer of the zirconium-based metal-organic framework membrane material.

22. The method according to any one of claims 10-21, characterized in that, The reaction was carried out at normal pressure in an air atmosphere.

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