Method for preparing high-performance inorganic molecular sieve membrane by dehydrating and refining organic matters
By adding antibacterial agents and optimizing the pore structure during the preparation of inorganic molecular sieve membranes, the problems of antibacterial agent stability and water permeability were solved, resulting in the preparation of a molecular sieve membrane with broad-spectrum antibacterial properties and high water permeability, suitable for medical equipment, food packaging, and water treatment systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2026-03-31
AI Technical Summary
Existing inorganic molecular sieve membranes suffer from problems in terms of antibacterial properties, such as poor stability of antibacterial agents, easy loss of antibacterial agents, low crystallinity and stability, resulting in insufficient water permeability.
By employing a combination of silicon source, aluminum source, organic template agent and antibacterial agent, and through steps such as spin coating, drying, crystallization, calcination, hydrothermal treatment and acid-base treatment, the antibacterial agent is ensured to be uniformly distributed in the molecular sieve membrane and the pore structure is optimized.
A high-performance inorganic molecular sieve membrane with broad-spectrum antibacterial properties and high water permeability was prepared. It can inhibit bacterial growth for a long time and is suitable for medical equipment, food packaging and water treatment systems, improving separation performance and permeability.
Smart Images
Figure CN121755066A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of inorganic molecular sieve membrane technology, specifically a method for preparing high-performance inorganic molecular sieve membranes by dehydrating and refining organic matter. Background Technology
[0002] With social development and technological advancements, antibacterial materials are increasingly widely used in medical, food, and environmental protection fields. Traditional methods for preparing antibacterial materials often suffer from problems such as short-lasting antibacterial effects, narrow antibacterial spectrum, and low safety. To overcome these shortcomings, researchers have been searching for new preparation methods and technologies to achieve more efficient and safer antibacterial performance. Currently, inorganic molecular sieve membranes, due to their unique pore structure and excellent separation performance, are widely used in filtration and separation. However, traditional inorganic molecular sieve membranes still have certain limitations in terms of antibacterial performance. To improve the antibacterial performance of inorganic molecular sieve membranes, researchers have attempted to modify their surfaces through various methods. Adding antibacterial agents is an effective method, but ensuring that the antibacterial agent is uniformly distributed, persistently stable, and has good biocompatibility within the molecular sieve membrane remains a problem to be solved.
[0003] Existing preparation methods often have the following shortcomings: the antibacterial agent has poor stability and is easily lost during application, reducing its antibacterial effect. Simultaneously, the crystallinity and stability of the molecular sieve membrane are not high enough, resulting in insufficient water permeability. Summary of the Invention
[0004] The purpose of this invention is to provide a method for preparing high-performance inorganic molecular sieve membranes by dehydrating and refining organic matter in order to solve the problems mentioned above.
[0005] The technical solution adopted in this invention is as follows: a method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter, the preparation method comprising the following steps:
[0006] S1: Select raw materials, including 50-70 parts by weight of suitable silicon source, 5-10 parts by weight of aluminum source, 10-20 parts by weight of organic template agent and 1-5 parts by weight of antibacterial agent as raw materials.
[0007] S2: Prepare a sol by mixing silicon source, aluminum source and organic template agent in a certain proportion, adding deionized water and stirring evenly to form a uniform sol;
[0008] S3: Add an antibacterial agent during the preparation of the sol and mix it evenly.
[0009] S4: Coating the substrate, the prepared sol containing antibacterial agent is uniformly coated onto the substrate material using a spin coating method;
[0010] S5: Drying: Place the coated base material in an oven and gradually heat it to 100-150℃. Dry for 2-4 hours to remove moisture from the sol.
[0011] S6: Place the dried substrate material into a sealed container, add deionized water, and maintain a certain humidity. Then place the sealed container in an oven and heat it to 100-150℃ for crystallization for 24-48 hours;
[0012] S7: Take out the crystallized molecular sieve membrane, place it in a muffle furnace, and calcine it to remove the organic template agent, thereby obtaining a high-performance inorganic molecular sieve membrane.
[0013] S8: The prepared high-performance inorganic molecular sieve membrane is subjected to hydrothermal treatment and acid-base treatment;
[0014] S9: Next, performance testing is performed on the prepared high-performance inorganic molecular sieve membrane, including porosity, pore size distribution, water permeability, and separation performance.
[0015] S10: Conduct antibacterial performance testing. Evaluate the antibacterial effect of the molecular sieve membrane through antibacterial activity tests (such as ISO 20776-1, ASTM E2149, etc.).
[0016] S11: The entire inorganic molecular sieve membrane preparation process can be completed by collecting and packaging the prepared inorganic molecular sieve membrane.
[0017] In a preferred embodiment, in step S1, the silicon source is selected from silica sol, tetraethyl orthosilicate, etc., the aluminum source is selected from sodium aluminate, aluminum nitrate, etc., and the organic template agent can be selected from tetrapropylammonium hydroxide (TPAOH) or hexadecyltrimethylammonium bromide (CTAB).
[0018] In a preferred embodiment, in step S2, a mechanical stirrer is used to stir the mixture at a speed of 300-500 rpm for about 30 minutes until a uniform sol is formed.
[0019] In a preferred embodiment, in step S1, the antibacterial agent comprises:
[0020] Silver nitrate (AgNO3): 1 part by weight;
[0021] Polyvinylpyrrolidone (PVP): 0.5 parts by weight;
[0022] Nano titanium dioxide (TiO2): 0.5 parts by weight;
[0023] Sodium carboxymethyl cellulose (CMC): 0.2 parts by weight;
[0024] Deionized water: 97.8 parts by weight.
[0025] In a preferred embodiment, step S3, the method for preparing the antibacterial agent includes: first, adding 0.2 parts by weight of sodium carboxymethyl cellulose to 97.8 parts by weight of deionized water and stirring until completely dissolved to form a stable suspension; then, adding 0.5 parts by weight of nano-titanium dioxide to the above suspension and continuing to stir to ensure uniform dispersion of nanoparticles; S13: then, adding 1 part by weight of silver nitrate and 0.5 parts by weight of polyvinylpyrrolidone to the suspension and continuing to stir until the silver nitrate is completely dissolved to form a uniform composite antibacterial agent.
[0026] In a preferred embodiment, step S4 specifically includes the following steps:
[0027] Secure the substrate material on the sample stage of the spin coater, ensuring its surface is flat, clean, and dust-free. Then, using a pipette or dropper, carefully drop an appropriate amount of sol containing the antibacterial agent onto the center of the substrate material. Start the spin coater and adjust to an appropriate speed, between 500-2000 rpm. The speed selection depends on the desired coating thickness and the viscosity of the sol. During rotation, the sol will diffuse outwards due to centrifugal force, uniformly covering the surface of the substrate material. After a period of rotation, the solvent in the sol will gradually evaporate, leaving a uniform film layer. Finally, turn off the spin coater, slowly stop the rotation, remove the substrate material, and place it in a desiccator to further remove residual solvent, ensuring the uniformity and integrity of the film layer. The key to this step is controlling the amount of sol added, the rotation speed, and the time to ensure a molecular sieve membrane of the desired thickness and uniformity.
[0028] In a preferred embodiment, in step S7, the temperature is increased to 500-600°C at a rate of 1-2°C / min during the roasting process and maintained for 2-4 hours. The roasting temperature is set to 550°C, and the muffle furnace atmosphere is an air or nitrogen protective atmosphere. During the cooling process, the temperature is reduced to below 100°C through a programmed cooling process (2-5°C / min) and then allowed to cool naturally.
[0029] In a preferred embodiment, in step S8, during the hydrothermal treatment process, the calcined molecular sieve membrane is placed in deionized water, heated to 100-150°C, and treated for 2-4 hours.
[0030] In a preferred embodiment, in step S8, the molecular sieve membrane is soaked in dilute hydrochloric acid, dilute nitric acid, or sodium hydroxide solution during the acid-base treatment process to optimize its pore structure and performance.
[0031] In a preferred embodiment, step S10, the antibacterial performance test includes: first, selecting the sample to be tested and the control sample, and ensuring that all sample surfaces are clean; second, preparing a standard strain suspension of a certain concentration, using Staphylococcus aureus and Escherichia coli, etc.; then, uniformly coating the strain suspension onto the sample surface and incubating; next, performing an antibacterial activity assessment by measuring the bacterial survival rate or colony count on the sample surface to determine the antibacterial performance of the sample to be tested.
[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:
[0033] 1. In this invention, by adding antibacterial agents (silver nitrate and nano-titanium dioxide) during the preparation process and ensuring their uniform distribution within the molecular sieve membrane, the antibacterial agents used exhibit inhibitory effects on a variety of microorganisms, including common Staphylococcus aureus and Escherichia coli. This broad-spectrum antibacterial property enables the molecular sieve membrane to function effectively in various application environments, whether in medical devices, food packaging, or water treatment systems, thereby effectively reducing the risk of bacterial infection. Furthermore, it maintains its antibacterial activity within the molecular sieve membrane for an extended period. This means that the prepared inorganic molecular sieve membrane not only possesses highly efficient antibacterial capabilities initially but also continuously inhibits bacterial growth and reproduction during use, thus extending its service life.
[0034] 2. In this invention, the pore structure of the molecular sieve membrane can be optimized through hydrothermal treatment and acid-base treatment steps, thereby improving its separation performance. Hydrothermal treatment helps improve the crystallinity and stability of the molecular sieve membrane, while acid-base treatment can adjust the pore size and distribution, optimizing the permeability and selectivity of the molecular sieve membrane. These treatment steps enable the prepared high-performance inorganic molecular sieve membrane to exhibit excellent performance in filtration, separation, and other fields, improving water permeability while maintaining the separation efficiency for specific molecules. This provides a more efficient and reliable solution for industrial applications requiring high-efficiency separation and purification processes. Attached Figure Description
[0035] Figure 1 This is a schematic diagram illustrating the process principle of the present invention. Detailed Implementation
[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0037] Reference Figure 1 ,
[0038] Example 1:
[0039] A method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter, the method comprising the following steps:
[0040] S1: Select raw materials, including 50 parts by weight of silicon source, 5 parts by weight of aluminum source, 10 parts by weight of organic template agent and 1 part by weight of antibacterial agent.
[0041] S2: Prepare a sol by mixing silicon source, aluminum source and organic template agent in a certain proportion, adding deionized water and stirring evenly to form a uniform sol;
[0042] S3: Add an antibacterial agent during the preparation of the sol and mix it evenly.
[0043] S4: Coating the substrate, the prepared sol containing antibacterial agent is uniformly coated onto the substrate material using a spin coating method;
[0044] S5: Drying: Place the coated base material in an oven and gradually heat it to 100-150℃. Dry for 2-4 hours to remove moisture from the sol.
[0045] S6: Place the dried substrate material into a sealed container, add deionized water, and maintain a certain humidity. Then place the sealed container in an oven and heat it to 100-150℃ for crystallization for 24-48 hours;
[0046] S7: Take out the crystallized molecular sieve membrane, place it in a muffle furnace, and calcine it to remove the organic template agent, thereby obtaining a high-performance inorganic molecular sieve membrane.
[0047] S8: The prepared high-performance inorganic molecular sieve membrane is subjected to hydrothermal treatment and acid-base treatment;
[0048] S9: Next, performance testing is performed on the prepared high-performance inorganic molecular sieve membrane, including porosity, pore size distribution, water permeability, and separation performance.
[0049] S10: Conduct antibacterial performance testing. Evaluate the antibacterial effect of the molecular sieve membrane through antibacterial activity tests (such as ISO20776-1, ASTM E2149, etc.).
[0050] S11: The entire inorganic molecular sieve membrane preparation process can be completed by collecting and packaging the prepared inorganic molecular sieve membrane.
[0051] In step S1, the silicon source can be silica sol, tetraethyl orthosilicate, etc., the aluminum source can be sodium aluminate or aluminum nitrate, and the organic template agent can be tetrapropylammonium hydroxide (TPAOH) or hexadecyltrimethylammonium bromide (CTAB).
[0052] In step S2, use a mechanical stirrer to stir the mixture at a speed of 300-500 rpm for about 30 minutes until a uniform sol is formed.
[0053] In step S1, the antibacterial agent includes:
[0054] Silver nitrate (AgNO3): 1 part by weight;
[0055] Polyvinylpyrrolidone (PVP): 0.5 parts by weight;
[0056] Nano titanium dioxide (TiO2): 0.5 parts by weight;
[0057] Sodium carboxymethyl cellulose (CMC): 0.2 parts by weight;
[0058] Deionized water: 97.8 parts by weight.
[0059] In step S3, the preparation method of the antibacterial agent includes: first, adding 0.2 parts by weight of sodium carboxymethyl cellulose to 97.8 parts by weight of deionized water and stirring until completely dissolved to form a stable suspension; then, adding 0.5 parts by weight of nano-titanium dioxide to the above suspension and continuing to stir to ensure uniform dispersion of nanoparticles; S13: then, adding 1 part by weight of silver nitrate and 0.5 parts by weight of polyvinylpyrrolidone to the suspension and continuing to stir until the silver nitrate is completely dissolved to form a uniform composite antibacterial agent.
[0060] Step S4 specifically includes the following steps:
[0061] Secure the substrate material on the sample stage of the spin coater, ensuring its surface is flat, clean, and dust-free. Then, using a pipette or dropper, carefully drop an appropriate amount of sol containing the antibacterial agent onto the center of the substrate material. Start the spin coater and adjust to an appropriate speed, between 500-2000 rpm. The speed selection depends on the desired coating thickness and the viscosity of the sol. During rotation, the sol will diffuse outwards due to centrifugal force, uniformly covering the surface of the substrate material. After a period of rotation, the solvent in the sol will gradually evaporate, leaving a uniform film layer. Finally, turn off the spin coater, slowly stop the rotation, remove the substrate material, and place it in a desiccator to further remove residual solvent, ensuring the uniformity and integrity of the film layer. The key to this step is controlling the amount of sol added, the rotation speed, and the time to ensure a molecular sieve membrane of the desired thickness and uniformity.
[0062] In step S7, the temperature is increased to 500-600℃ at a rate of 1-2℃ / min during calcination and maintained for 2-4 hours. The calcination temperature is set to 550℃, and the muffle furnace atmosphere is an air or nitrogen protective atmosphere. During cooling, the temperature is reduced to below 100℃ through a programmed cooling process (2-5℃ / min) followed by natural cooling.
[0063] In step S8, during the hydrothermal treatment process, the calcined molecular sieve membrane is placed in deionized water, heated to 100-150℃, and treated for 2-4 hours.
[0064] In step S8, the molecular sieve membrane is soaked in dilute hydrochloric acid, dilute nitric acid, or sodium hydroxide solution during the acid-base treatment process to optimize its pore structure and performance.
[0065] In step S10, the antimicrobial performance test includes: first, selecting the sample to be tested and the control sample, and ensuring that all sample surfaces are clean; second, preparing a standard strain suspension of a certain concentration, using Staphylococcus aureus and Escherichia coli, etc.; then, uniformly coating the strain suspension on the sample surface and incubating it; next, performing an antimicrobial activity assessment by measuring the bacterial survival rate or colony count on the sample surface to determine the antimicrobial performance of the sample to be tested.
[0066] Based on the above, we can conclude that:
[0067] In this invention, by adding antibacterial agents (silver nitrate and nano-titanium dioxide) during the preparation process and ensuring their uniform distribution within the molecular sieve membrane, the antibacterial agents exhibit inhibitory effects against a variety of microorganisms, including common Staphylococcus aureus and Escherichia coli. This broad-spectrum antibacterial property enables the molecular sieve membrane to function effectively in various application environments, including medical devices, food packaging, and water treatment systems, thereby reducing the risk of bacterial infection. Furthermore, it maintains its antibacterial activity within the molecular sieve membrane for an extended period. This means that the prepared inorganic molecular sieve membrane not only possesses highly efficient antibacterial capabilities initially but also continuously inhibits bacterial growth and reproduction during use, thus extending its service life.
[0068] In this invention, the pore structure of the molecular sieve membrane can be optimized through hydrothermal treatment and acid-base treatment steps, thereby improving its separation performance. Hydrothermal treatment helps improve the crystallinity and stability of the molecular sieve membrane, while acid-base treatment can adjust the pore size and distribution, optimizing the permeability and selectivity of the molecular sieve membrane. These treatment steps enable the prepared high-performance inorganic molecular sieve membrane to exhibit excellent performance in filtration, separation, and other fields, improving water permeability while maintaining the separation efficiency for specific molecules. This provides a more efficient and reliable solution for industrial applications requiring high-efficiency separation and purification processes.
[0069] Example 2:
[0070] A method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter, the method comprising the following steps:
[0071] S1: Select raw materials, including 70 parts by weight of silicon source, 10 parts by weight of aluminum source, 20 parts by weight of organic template agent and 5 parts by weight of antibacterial agent.
[0072] S2: Prepare a sol by mixing silicon source, aluminum source and organic template agent in a certain proportion, adding deionized water and stirring evenly to form a uniform sol;
[0073] S3: Add an antibacterial agent during the preparation of the sol and mix it evenly.
[0074] S4: Coating the substrate, the prepared sol containing antibacterial agent is uniformly coated onto the substrate material using a spin coating method;
[0075] S5: Drying: Place the coated base material in an oven and gradually heat it to 100-150℃. Dry for 2-4 hours to remove moisture from the sol.
[0076] S6: Place the dried substrate material into a sealed container, add deionized water, and maintain a certain humidity. Then place the sealed container in an oven and heat it to 100-150℃ for crystallization for 24-48 hours;
[0077] S7: Take out the crystallized molecular sieve membrane, place it in a muffle furnace, and calcine it to remove the organic template agent, thereby obtaining a high-performance inorganic molecular sieve membrane.
[0078] S8: The prepared high-performance inorganic molecular sieve membrane is subjected to hydrothermal treatment and acid-base treatment;
[0079] S9: Next, performance testing is performed on the prepared high-performance inorganic molecular sieve membrane, including porosity, pore size distribution, water permeability, and separation performance.
[0080] S10: Conduct antibacterial performance testing. Evaluate the antibacterial effect of the molecular sieve membrane through antibacterial activity tests (such as ISO20776-1, ASTM E2149, etc.).
[0081] S11: The entire inorganic molecular sieve membrane preparation process can be completed by collecting and packaging the prepared inorganic molecular sieve membrane.
[0082] In step S1, the silicon source can be silica sol, tetraethyl orthosilicate, etc., the aluminum source can be sodium aluminate or aluminum nitrate, and the organic template agent can be tetrapropylammonium hydroxide (TPAOH) or hexadecyltrimethylammonium bromide (CTAB).
[0083] In step S2, use a mechanical stirrer to stir the mixture at a speed of 300-500 rpm for about 30 minutes until a uniform sol is formed.
[0084] In step S1, the antibacterial agent includes:
[0085] Silver nitrate (AgNO3): 1 part by weight;
[0086] Polyvinylpyrrolidone (PVP): 0.5 parts by weight;
[0087] Nano titanium dioxide (TiO2): 0.5 parts by weight;
[0088] Sodium carboxymethyl cellulose (CMC): 0.2 parts by weight;
[0089] Deionized water: 97.8 parts by weight.
[0090] In step S3, the preparation method of the antibacterial agent includes: first, adding 0.2 parts by weight of sodium carboxymethyl cellulose to 97.8 parts by weight of deionized water and stirring until completely dissolved to form a stable suspension; then, adding 0.5 parts by weight of nano-titanium dioxide to the above suspension and continuing to stir to ensure uniform dispersion of nanoparticles; S13: then, adding 1 part by weight of silver nitrate and 0.5 parts by weight of polyvinylpyrrolidone to the suspension and continuing to stir until the silver nitrate is completely dissolved to form a uniform composite antibacterial agent.
[0091] Step S4 specifically includes the following steps:
[0092] Secure the substrate material on the sample stage of the spin coater, ensuring its surface is flat, clean, and dust-free. Then, using a pipette or dropper, carefully drop an appropriate amount of sol containing the antibacterial agent onto the center of the substrate material. Start the spin coater and adjust to an appropriate speed, between 500-2000 rpm. The speed selection depends on the desired coating thickness and the viscosity of the sol. During rotation, the sol will diffuse outwards due to centrifugal force, uniformly covering the surface of the substrate material. After a period of rotation, the solvent in the sol will gradually evaporate, leaving a uniform film layer. Finally, turn off the spin coater, slowly stop the rotation, remove the substrate material, and place it in a desiccator to further remove residual solvent, ensuring the uniformity and integrity of the film layer. The key to this step is controlling the amount of sol added, the rotation speed, and the time to ensure a molecular sieve membrane of the desired thickness and uniformity.
[0093] In step S7, the temperature is increased to 500-600℃ at a rate of 1-2℃ / min during calcination and maintained for 2-4 hours. The calcination temperature is set to 550℃, and the muffle furnace atmosphere is an air or nitrogen protective atmosphere. During cooling, the temperature is reduced to below 100℃ through a programmed cooling process (2-5℃ / min) followed by natural cooling.
[0094] In step S8, during the hydrothermal treatment process, the calcined molecular sieve membrane is placed in deionized water, heated to 100-150℃, and treated for 2-4 hours.
[0095] In step S8, the molecular sieve membrane is soaked in dilute hydrochloric acid, dilute nitric acid, or sodium hydroxide solution during the acid-base treatment process to optimize its pore structure and performance.
[0096] In step S10, the antimicrobial performance test includes: first, selecting the sample to be tested and the control sample, and ensuring that all sample surfaces are clean; second, preparing a standard strain suspension of a certain concentration, using Staphylococcus aureus and Escherichia coli, etc.; then, uniformly coating the strain suspension on the sample surface and incubating it; next, performing an antimicrobial activity assessment by measuring the bacterial survival rate or colony count on the sample surface to determine the antimicrobial performance of the sample to be tested.
[0097] Based on the above, we can conclude that:
[0098] In this invention, by adding antibacterial agents (silver nitrate and nano-titanium dioxide) during the preparation process and ensuring their uniform distribution within the molecular sieve membrane, the antibacterial agents exhibit inhibitory effects against a variety of microorganisms, including common Staphylococcus aureus and Escherichia coli. This broad-spectrum antibacterial property enables the molecular sieve membrane to function effectively in various application environments, including medical devices, food packaging, and water treatment systems, thereby reducing the risk of bacterial infection. Furthermore, it maintains its antibacterial activity within the molecular sieve membrane for an extended period. This means that the prepared inorganic molecular sieve membrane not only possesses highly efficient antibacterial capabilities initially but also continuously inhibits bacterial growth and reproduction during use, thus extending its service life.
[0099] In this invention, the pore structure of the molecular sieve membrane can be optimized through hydrothermal treatment and acid-base treatment steps, thereby improving its separation performance. Hydrothermal treatment helps improve the crystallinity and stability of the molecular sieve membrane, while acid-base treatment can adjust the pore size and distribution, optimizing the permeability and selectivity of the molecular sieve membrane. These treatment steps enable the prepared high-performance inorganic molecular sieve membrane to exhibit excellent performance in filtration, separation, and other fields, improving water permeability while maintaining the separation efficiency for specific molecules. This provides a more efficient and reliable solution for industrial applications requiring high-efficiency separation and purification processes.
[0100] Example 3:
[0101] A method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter, the method comprising the following steps:
[0102] S1: Select raw materials, including 60 parts by weight of silicon source, 8 parts by weight of aluminum source, 15 parts by weight of organic template agent and 3 parts by weight of antibacterial agent.
[0103] S2: Prepare a sol by mixing silicon source, aluminum source and organic template agent in a certain proportion, adding deionized water and stirring evenly to form a uniform sol;
[0104] S3: Add an antibacterial agent during the preparation of the sol and mix it evenly.
[0105] S4: Coating the substrate, the prepared sol containing antibacterial agent is uniformly coated onto the substrate material using a spin coating method;
[0106] S5: Drying: Place the coated base material in an oven and gradually heat it to 100-150℃. Dry for 2-4 hours to remove moisture from the sol.
[0107] S6: Place the dried substrate material into a sealed container, add deionized water, and maintain a certain humidity. Then place the sealed container in an oven and heat it to 100-150℃ for crystallization for 24-48 hours;
[0108] S7: Take out the crystallized molecular sieve membrane, place it in a muffle furnace, and calcine it to remove the organic template agent, thereby obtaining a high-performance inorganic molecular sieve membrane.
[0109] S8: The prepared high-performance inorganic molecular sieve membrane is subjected to hydrothermal treatment and acid-base treatment;
[0110] S9: Next, performance testing is performed on the prepared high-performance inorganic molecular sieve membrane, including porosity, pore size distribution, water permeability, and separation performance.
[0111] S10: Conduct antibacterial performance testing. Evaluate the antibacterial effect of the molecular sieve membrane through antibacterial activity tests (such as ISO20776-1, ASTM E2149, etc.).
[0112] S11: The entire inorganic molecular sieve membrane preparation process can be completed by collecting and packaging the prepared inorganic molecular sieve membrane.
[0113] In step S1, the silicon source can be silica sol, tetraethyl orthosilicate, etc., the aluminum source can be sodium aluminate or aluminum nitrate, and the organic template agent can be tetrapropylammonium hydroxide (TPAOH) or hexadecyltrimethylammonium bromide (CTAB).
[0114] In step S2, use a mechanical stirrer to stir the mixture at a speed of 300-500 rpm for about 30 minutes until a uniform sol is formed.
[0115] In step S1, the antibacterial agent includes:
[0116] Silver nitrate (AgNO3): 1 part by weight;
[0117] Polyvinylpyrrolidone (PVP): 0.5 parts by weight;
[0118] Nano titanium dioxide (TiO2): 0.5 parts by weight;
[0119] Sodium carboxymethyl cellulose (CMC): 0.2 parts by weight;
[0120] Deionized water: 97.8 parts by weight.
[0121] In step S3, the preparation method of the antibacterial agent includes: first, adding 0.2 parts by weight of sodium carboxymethyl cellulose to 97.8 parts by weight of deionized water and stirring until completely dissolved to form a stable suspension; then, adding 0.5 parts by weight of nano-titanium dioxide to the above suspension and continuing to stir to ensure uniform dispersion of nanoparticles; S13: then, adding 1 part by weight of silver nitrate and 0.5 parts by weight of polyvinylpyrrolidone to the suspension and continuing to stir until the silver nitrate is completely dissolved to form a uniform composite antibacterial agent.
[0122] Step S4 specifically includes the following steps:
[0123] Secure the substrate material on the sample stage of the spin coater, ensuring its surface is flat, clean, and dust-free. Then, using a pipette or dropper, carefully drop an appropriate amount of sol containing the antibacterial agent onto the center of the substrate material. Start the spin coater and adjust to an appropriate speed, between 500-2000 rpm. The speed selection depends on the desired coating thickness and the viscosity of the sol. During rotation, the sol will diffuse outwards due to centrifugal force, uniformly covering the surface of the substrate material. After a period of rotation, the solvent in the sol will gradually evaporate, leaving a uniform film layer. Finally, turn off the spin coater, slowly stop the rotation, remove the substrate material, and place it in a desiccator to further remove residual solvent, ensuring the uniformity and integrity of the film layer. The key to this step is controlling the amount of sol added, the rotation speed, and the time to ensure a molecular sieve membrane of the desired thickness and uniformity.
[0124] In step S7, the temperature is increased to 500-600℃ at a rate of 1-2℃ / min during calcination and maintained for 2-4 hours. The calcination temperature is set to 550℃, and the muffle furnace atmosphere is an air or nitrogen protective atmosphere. During cooling, the temperature is reduced to below 100℃ through a programmed cooling process (2-5℃ / min) followed by natural cooling.
[0125] In step S8, during the hydrothermal treatment process, the calcined molecular sieve membrane is placed in deionized water, heated to 100-150℃, and treated for 2-4 hours.
[0126] In step S8, the molecular sieve membrane is soaked in dilute hydrochloric acid, dilute nitric acid, or sodium hydroxide solution during the acid-base treatment process to optimize its pore structure and performance.
[0127] In step S10, the antimicrobial performance test includes: first, selecting the sample to be tested and the control sample, and ensuring that all sample surfaces are clean; second, preparing a standard strain suspension of a certain concentration, using Staphylococcus aureus and Escherichia coli, etc.; then, uniformly coating the strain suspension on the sample surface and incubating it; next, performing an antimicrobial activity assessment by measuring the bacterial survival rate or colony count on the sample surface to determine the antimicrobial performance of the sample to be tested.
[0128] Based on the above, we can conclude that:
[0129] In this invention, by adding antibacterial agents (silver nitrate and nano-titanium dioxide) during the preparation process and ensuring their uniform distribution within the molecular sieve membrane, the antibacterial agents exhibit inhibitory effects against a variety of microorganisms, including common Staphylococcus aureus and Escherichia coli. This broad-spectrum antibacterial property enables the molecular sieve membrane to function effectively in various application environments, including medical devices, food packaging, and water treatment systems, thereby reducing the risk of bacterial infection. Furthermore, it maintains its antibacterial activity within the molecular sieve membrane for an extended period. This means that the prepared inorganic molecular sieve membrane not only possesses highly efficient antibacterial capabilities initially but also continuously inhibits bacterial growth and reproduction during use, thus extending its service life.
[0130] In this invention, the pore structure of the molecular sieve membrane can be optimized through hydrothermal treatment and acid-base treatment steps, thereby improving its separation performance. Hydrothermal treatment helps improve the crystallinity and stability of the molecular sieve membrane, while acid-base treatment can adjust the pore size and distribution, optimizing the permeability and selectivity of the molecular sieve membrane. These treatment steps enable the prepared high-performance inorganic molecular sieve membrane to exhibit excellent performance in filtration, separation, and other fields, improving water permeability while maintaining the separation efficiency for specific molecules. This provides a more efficient and reliable solution for industrial applications requiring high-efficiency separation and purification processes.
[0131] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the term "comprising" or any other variations thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.
[0132] The foregoing description enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for preparing a high performance inorganic molecular sieve membrane for dehydration and purification of organic substances, characterized by: The preparation method comprises the following steps: S1: selecting raw materials, selecting suitable silicon source 50-70 parts by weight, aluminum source 5-10 parts by weight, organic template agent 10-20 parts by weight and antibacterial agent 1-5 parts by weight as raw materials; S2: preparing sol, mixing silicon source, aluminum source and organic template agent according to the proportion, adding deionized water, stirring uniformly to form uniform sol; S3: adding antibacterial agent during the preparation of sol and uniformly mixing; S4: coating the substrate, uniformly coating the prepared sol containing antibacterial agent on the substrate material by using the spin coating method; S5: drying, placing the coated substrate material in an oven, gradually heating to 100-150℃, and drying for 2-4 hours to remove the water in the sol; S6: placing the dried substrate material in a sealed container, adding deionized water to maintain a certain humidity, then placing the sealed container in an oven, heating to 100-150℃, and crystallizing for 24-48 hours; S7: taking out the crystallized molecular sieve membrane, placing it in a muffle furnace, and calcining to remove the organic template agent to obtain a high-performance inorganic molecular sieve membrane; S8: hydrothermal treatment and acid-base treatment are performed on the prepared high-performance inorganic molecular sieve membrane; S9: performance detection, the prepared high-performance inorganic molecular sieve membrane is subjected to performance detection, including porosity, pore size distribution, water permeability, separation performance; S10: antibacterial performance detection, the antibacterial effect of the molecular sieve membrane is evaluated through antibacterial activity test; S11: collecting and packaging the prepared inorganic molecular sieve membrane to end the entire preparation process of the inorganic molecular sieve membrane.
2. The method for preparing a high performance inorganic molecular sieve membrane for organic dehydration and purification according to claim 1, characterized in that: In the step S1, the silicon source is selected from silica sol, tetraethyl orthosilicate, etc., the aluminum source is selected from sodium metaaluminate and aluminum nitrate, and the organic template agent can be selected from tetrapropylammonium hydroxide and cetyltrimethylammonium bromide.
3. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S2, the mixture is stirred at a speed of 300-500 rpm for about 30 minutes until a uniform sol is formed.
4. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S1, the antibacterial agent comprises: Silver nitrate: 1 part by weight; Polyvinylpyrrolidone: 0.5 parts by weight; Nano titanium dioxide: 0.5 parts by weight; Sodium carboxymethyl cellulose: 0.2 parts by weight; Deionized water: 97.8 parts by weight.
5. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S3, the preparation method of the antibacterial agent comprises: first, adding 0.2 parts by weight of sodium carboxymethyl cellulose to 97.8 parts by weight of deionized water, stirring until completely dissolved to form a stable suspension; then, adding 0.5 parts by weight of nano titanium dioxide to the suspension, continuing to stir to ensure uniform dispersion of the nanoparticles; S13: then, adding 1 part of silver nitrate and 0.5 parts by weight of polyvinylpyrrolidone to the suspension, continuing to stir until the silver nitrate is completely dissolved to form a uniform composite antibacterial agent.
6. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S4, the following steps are specifically included: The substrate material is fixed on the sample stage of the spin coater, and the surface is ensured to be flat, clean and dust-free. Then, an appropriate amount of sol containing the antibacterial agent is taken using a pipette or dropper and carefully dropped at the center of the substrate material. The spin coater is started and adjusted to the appropriate rotation speed, between 500-2000 rpm, depending on the desired thickness of the coating layer and the viscosity of the sol. During the rotation, the sol spreads outward due to centrifugal force and uniformly covers the surface of the substrate material. After a certain period of rotation, the solvent in the sol gradually evaporates, leaving a uniform film layer. Finally, the spin coater is turned off, the rotation is slowly stopped, and the substrate material is removed and placed in a desiccator to further remove residual solvents, ensuring the uniformity and integrity of the film layer. The key to this step is to control the amount of sol added, the rotation speed and time to ensure the desired thickness and uniformity of the molecular sieve membrane.
7. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S7, the temperature is raised at a rate of 1-2℃ / min to 500-600℃ during calcination, and maintained for 2-4 hours. The calcination temperature is set to 550℃, and the muffle furnace atmosphere is air or nitrogen protective atmosphere. During cooling, the temperature is programmed to below 100℃ and then naturally cooled.
8. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S8, the calcined molecular sieve membrane is placed in deionized water during hydrothermal treatment, and the temperature is raised to 100-150℃ and treated for 2-4 hours.
9. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S8, during acid-base treatment, the molecular sieve membrane is immersed in dilute hydrochloric acid, dilute nitric acid or sodium hydroxide solution.
10. The method for preparing a high-performance inorganic molecular sieve membrane by dehydration and purification of organic matter as described in claim 1, characterized in that: In the step S10, the antibacterial performance detection includes: first, selecting the test sample and control sample, and ensuring that all sample surfaces are clean; second, preparing a standard strain suspension of a certain concentration, using Staphylococcus aureus and Escherichia coli, etc.; then, evenly coating the strain suspension on the sample surface and incubating; next, evaluating the antibacterial activity by measuring the bacterial survival rate or colony number on the sample surface to determine the antibacterial performance of the test sample.