Preparation method of a modified anti-bacterial reverse osmosis membrane by terramycin
By grafting terbinazone onto the surface of the reverse osmosis membrane, the problem of easy fouling of the reverse osmosis membrane is solved, achieving highly efficient antibacterial properties and extended service life.
Patent Information
- Application Number
- CN202310694785.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-12
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2043-06-12
AI Technical Summary
Existing reverse osmosis membranes are susceptible to fouling by bacteria, colloids, and particles, leading to a decrease in permeate flux and permeate quality, and conventional antibacterial measures may harm health.
A method for preparing a reverse osmosis membrane modified with terbinazone was adopted. Terbinazone was grafted onto the membrane surface by reacting glutaraldehyde with the amide bonds on the surface of the polyamide membrane, thereby improving the antibacterial performance of the membrane by utilizing its antibacterial properties.
It significantly improves the antibacterial properties of reverse osmosis membranes, extends their service life, and achieves highly efficient antibacterial effects under mild conditions.
Smart Images
Figure CN116603400B_ABST
Abstract
Description
Technical fields:
[0001] This invention relates to the field of marine fungal bioactive metabolites and reverse osmosis membrane preparation technology, specifically to a method for preparing an aspergillus terrestris-modified antibacterial reverse osmosis membrane. Background technology:
[0002] As more researchers develop processes to improve water purity, membrane-based water purification has emerged. Reverse osmosis membranes, as the least precise liquid separation membranes, have received considerable attention. Currently, the most widely used reverse osmosis membrane material is the polyamide thin-layer composite (PA-TFC) membrane. PA-TFC membranes are prepared by interfacial polymerization between m-phenylenediamine and trimesoyl chloride, using nanoporous polysulfone as a carrier. However, these PA-TFC membranes are susceptible to fouling by bacteria, colloids, and trapped particles, leading to a decrease in permeate flux and permeate quality. Currently, membrane cleaning and chlorination pretreatment are the main methods to mitigate fouling. However, frequent membrane cleaning can damage the membrane surface, and residual chlorine in the water after adding active chlorine can attack the amide bonds on the membrane surface. Byproducts produced from the reaction of chlorine with organic matter can also harm human health. Furthermore, antibacterial membranes containing metal ions or nanoparticles may release these ions and nanoparticles from the reverse osmosis membrane, potentially harming human and aquatic organisms. Therefore, improving the biofouling resistance of reverse osmosis membranes remains a crucial issue in practical applications.
[0003] To improve the antifouling and antibacterial properties of reverse osmosis membranes, researchers have explored various methods, such as incorporating antibacterial nanofillers into the membrane and grafting antibacterial polymers onto the membrane surface. Marine fungi, due to their abundant resources, short growth cycle, lack of seasonal limitations, and ability to be cultivated in large quantities artificially, have gained significant attention in scientific research and production. Aspergillus terrestris, a bioactive metabolite extracted from the marine Aspergillus terrestris fungus, is readily soluble in water, highly stable, and possesses various biological activities. Aspergillus terrestris is naturally harmless and is often used as a drug to inhibit the proliferation of various tumor cells, including breast cancer, cervical cancer, and liver cancer. In addition, aspergillus terrestris has been found to have excellent inhibitory effects on bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, as well as fungi such as Candida albicans. Furthermore, its abundant hydroxyl groups can bond with the terminal amino groups of polyamides, allowing it to be grafted onto the surface of polyamide reverse osmosis membranes, effectively improving the membrane's antibacterial properties. Currently, there is little research on surface modification of polyamide reverse osmosis membranes using aspergillus terrestris. Summary of the Invention:
[0004] The purpose of this invention is to provide a method for preparing an aspergillus terrestris-modified antibacterial reverse osmosis membrane. Specifically, it includes the following steps:
[0005] After cleaning the polysulfone-based membrane with deionized water, fix it on the clamp and dry it with an air knife. Pour the aqueous solution onto the surface of the polysulfone membrane. After a period of time, pour off the excess aqueous solution and dry it again with an air knife. Then pour the oil solution onto the surface of the base membrane. After a period of time, pour off the excess oil solution.
[0006] The membrane obtained above is placed in an oven and heat-treated for a period of time. After that, it is taken out and cleaned to obtain the reverse osmosis membrane.
[0007] The aforementioned reverse osmosis membrane was immersed in a mixed solution of glutaraldehyde and sulfuric acid, allowed to stand for a period of time, then excess solution was discarded and the membrane was dried. Finally, a solution of a certain concentration of terbinafine was poured onto the surface of the reverse osmosis membrane coated with glutaraldehyde. After heat treatment for a certain period of time, it was immersed in deionized water to obtain a terbinafine-modified antibacterial reverse osmosis membrane.
[0008] The aqueous solution is prepared by mixing 1.0–3.0% m-phenylenediamine, 1.0–2.0% dimethyl sulfoxide, 1.0–2.0% triethylamine, 2.0–3.0% camphor sulfonic acid, and 0.1–0.2% sodium dodecyl sulfate in an aqueous solution with a mass fraction of 1.0–3.0%, and then sonicating for a period of time to obtain the aqueous solution.
[0009] The oil phase solution is a 0.1-0.5% (w / w) solution of pyromellitic chlorohexane.
[0010] The heat treatment temperature is 60-80℃, the heat treatment time is 1-10 min, the standing time is 5 minutes, and the heat treatment time is 40-60 min.
[0011] The method for preparing the mixed solution of glutaraldehyde and sulfuric acid is as follows: prepare an aqueous solution of glutaraldehyde with a mass fraction of 0.01-0.05% and sulfuric acid with a mass fraction of 0.1-0.5%.
[0012] The aforementioned terbinafine solution has a concentration of 5–20 mg / ml.
[0013] The terbinafine-modified antibacterial reverse osmosis membrane has antibacterial properties.
[0014] The present invention has the following advantages over the prior art:
[0015] This invention innovatively prepares an aspergillus-modified antibacterial reverse osmosis membrane by grafting terbinazone onto the surface of a reverse osmosis membrane. Firstly, the aldehyde group of glutaraldehyde reacts with the amide bond or unreacted amino group on the polyamide reverse osmosis membrane, making it easy for glutaraldehyde to attach to the membrane surface. Then, using glutaraldehyde as a linker, oxytetracycline is grafted onto the membrane surface through the reaction between the unreacted aldehyde group of glutaraldehyde and the hydroxyl group of oxytetracycline. The antibacterial properties of terbinazone significantly improve the antibacterial activity of the reverse osmosis membrane, effectively extending its service life. The advantages of this invention are simple and mild reaction conditions, mature and effective operation methods, and significant antibacterial properties. Attached image description:
[0016] Figure 1 The image shows a scanning electron microscope (SEM) image of the surface structure of the terbinafine-modified antibacterial reverse osmosis membrane prepared in Example 1.
[0017] Figure 2 The image shows a scanning electron microscope (SEM) image of the surface structure of the blank control reverse osmosis membrane prepared in Comparative Example 1. Detailed implementation method:
[0018] The present invention will be described in detail below through specific embodiments, but the embodiments do not limit the scope of the present invention.
[0019] Example 1:
[0020] (1) Clean the polysulfone ultrafiltration membrane (molecular weight cutoff 30,000) with pure water and use it as a support layer for later use;
[0021] (2) Preparation of oil phase solution: Prepare an aqueous solution of m-phenylenediamine with a mass fraction of 2.0%;
[0022] (3) Preparation of oil phase solution: Prepare a 0.1% (w / w) solution of pyromellitic methyl chloride and hexane;
[0023] (4) Preparation of aromatic polyamide layer reverse osmosis membrane: Take out the polysulfone-based membrane and fix it on the glass plate. Use an air knife to blow dry the water. Pour the aqueous phase solution onto the surface of the polysulfone-based membrane. After 5 minutes, pour off the excess aqueous phase solution and blow dry with an air knife. Then pour the oil phase solution onto the membrane surface and react for 1 minute. Pour off the excess oil phase solution.
[0024] (5) The reverse osmosis membrane was immersed in a mixed solution of 0.04% glutaraldehyde and 0.1% sulfuric acid by mass, allowed to stand for 5 minutes, then the excess solution was poured off and the membrane was dried. Finally, a 10 mg / ml terbinafine solution was poured onto the surface of the reverse osmosis membrane coated with glutaraldehyde.
[0025] (6) Place the membrane obtained above in an oven at 60°C and heat treat for 1 hour; remove the membrane and rinse with pure water for later use.
[0026] Figure 1 The image shows a scanning electron microscope (SEM) image of the surface structure of the terbinafine-modified antibacterial reverse osmosis membrane prepared in Example 1.
[0027] Membrane flux and rejection rate testing: The modified reverse osmosis membrane was filtered for 1 hour at 2 MPa and 25°C using a 2000 ppm sodium chloride aqueous solution, and its initial permeate flux and rejection rate were then tested. The membrane flux and sodium chloride rejection rate were calculated using the following formulas.
[0028] Flux = Permeate volume / (Time × Membrane area)
[0029] Retention rate = (Feed solution conductivity - Permeate conductivity) / Feed solution conductivity
[0030] The initial permeation flux and salt rejection rate of the modified membrane were obtained by filtering a 2000ppm sodium chloride aqueous solution at 2MPa and 25℃, as shown in Table 1.
[0031] Antibacterial test: The membrane sample was uniformly dispersed in a diluted solution of *E. coli* or *Staphylococcus aureus*, and the suspension containing the membrane sample was placed in a shaker at 37°C for 3 hours. After contacting the culture with the membrane sample for 3 hours, the bacterial solution was further diluted 10⁻⁶. 1 Then, 100 μL was evenly added to an LB plate, and photographs and observations were taken. The same *E. coli* and *Staphylococcus aureus* suspensions were used in the blank control group, with the steps identical to the above except that no membrane sample was added. Colony counts were recorded and the inhibition rate was calculated. The formula for calculating the antibacterial rate (R) is as follows:
[0032]
[0033] Where R is the antibacterial rate, A is the number of colonies in the sample containing the membrane, and B is the number of colonies in the blank bacterial solution.
[0034] The experimental results of the reverse osmosis membrane prepared in Example 1 are shown in Table 2.
[0035] Example 2:
[0036] (1) Clean the polysulfone ultrafiltration membrane (molecular weight cutoff 30,000) with pure water and use it as a support layer for later use;
[0037] (2) Preparation of oil phase solution: Prepare an aqueous solution of m-phenylenediamine with a mass fraction of 2.0%;
[0038] (3) Preparation of oil phase solution: Prepare a 0.1% (w / w) solution of pyromellitic methyl chloride and hexane;
[0039] (4) Preparation of aromatic polyamide layer reverse osmosis membrane: Take out the polysulfone-based membrane and fix it on the glass plate. Use an air knife to blow dry the water. Pour the aqueous phase solution onto the surface of the polysulfone-based membrane. After 5 minutes, pour off the excess aqueous phase solution and blow dry with an air knife. Then pour the oil phase solution onto the membrane surface and react for 1 minute. Pour off the excess oil phase solution.
[0040] (5) The reverse osmosis membrane was immersed in a mixed solution of 0.04% glutaraldehyde and 0.1% sulfuric acid by mass, allowed to stand for 5 minutes, then the excess solution was poured off and the membrane was dried. Finally, a 5 mg / ml terbinafine solution was poured onto the surface of the reverse osmosis membrane coated with glutaraldehyde.
[0041] (6) Place the membrane obtained above in an oven at 60°C and heat treat for 1 hour; remove the membrane and rinse with pure water for later use.
[0042] Membrane flux and rejection rate testing: The modified reverse osmosis membrane was filtered for 1 hour at 2 MPa and 25°C using a 2000 ppm sodium chloride aqueous solution, and its initial permeate flux and rejection rate were then tested. The membrane flux and sodium chloride rejection rate were calculated using the following formulas.
[0043] Flux = Permeate volume / (Time × Membrane area)
[0044] Retention rate = (Feed solution conductivity - Permeate conductivity) / Feed solution conductivity
[0045] The initial permeation flux and salt rejection rate of the modified membrane were obtained by filtering a 2000ppm sodium chloride aqueous solution at 2MPa and 25℃, as shown in Table 1.
[0046] Antibacterial test: The membrane sample was uniformly dispersed in a diluted solution of *E. coli* or *Staphylococcus aureus*, and the suspension containing the membrane sample was placed in a shaker at 37°C for 3 hours. After contacting the culture with the membrane sample for 3 hours, the bacterial solution was further diluted 10⁻⁶. 1 Then, 100 μL was evenly added to an LB plate, and photographs and observations were taken. The same *E. coli* and *Staphylococcus aureus* suspensions were used in the blank control group, with the steps identical to the above except that no membrane sample was added. Colony counts were recorded and the inhibition rate was calculated. The formula for calculating the antibacterial rate (R) is as follows:
[0047]
[0048] Where R is the antibacterial rate, A is the number of colonies in the sample containing the membrane, and B is the number of colonies in the blank bacterial solution.
[0049] The experimental results of the reverse osmosis membrane prepared in Example 1 are shown in Table 2.
[0050] Example 3:
[0051] (1) Clean the polysulfone ultrafiltration membrane (molecular weight cutoff 30,000) with pure water and use it as a support layer for later use;
[0052] (2) Preparation of oil phase solution: Prepare an aqueous solution of m-phenylenediamine with a mass fraction of 2.0%;
[0053] (3) Preparation of oil phase solution: Prepare a 0.1% (w / w) solution of pyromellitic methyl chloride and hexane;
[0054] (4) Preparation of aromatic polyamide layer reverse osmosis membrane: Take out the polysulfone-based membrane and fix it on the glass plate. Use an air knife to blow dry the water. Pour the aqueous phase solution onto the surface of the polysulfone-based membrane. After 5 minutes, pour off the excess aqueous phase solution and blow dry with an air knife. Then pour the oil phase solution onto the membrane surface and react for 1 minute. Pour off the excess oil phase solution.
[0055] (5) The reverse osmosis membrane was immersed in a mixed solution of 0.04% glutaraldehyde and 0.1% sulfuric acid by mass, allowed to stand for 5 minutes, then the excess solution was poured off and the membrane was dried. Finally, a 15 mg / ml terbinafine solution was poured onto the surface of the reverse osmosis membrane coated with glutaraldehyde.
[0056] (6) Place the membrane obtained above in an oven at 60°C and heat treat for 1 hour; remove the membrane and rinse with pure water for later use.
[0057] Membrane flux and rejection rate testing: The modified reverse osmosis membrane was filtered for 1 hour at 2 MPa and 25°C using a 2000 ppm sodium chloride aqueous solution, and its initial permeate flux and rejection rate were then tested. The membrane flux and sodium chloride rejection rate were calculated using the following formulas.
[0058] Flux = Permeate volume / (Time × Membrane area)
[0059] Retention rate = (Feed solution conductivity - Permeate conductivity) / Feed solution conductivity
[0060] The initial permeation flux and salt rejection rate of the modified membrane were obtained by filtering a 2000ppm sodium chloride aqueous solution at 2MPa and 25℃, as shown in Table 1.
[0061] Antibacterial test: The membrane sample was uniformly dispersed in a diluted solution of *E. coli* or *Staphylococcus aureus*, and the suspension containing the membrane sample was placed in a shaker at 37°C for 3 hours. After contacting the culture with the membrane sample for 3 hours, the bacterial solution was further diluted 10⁻⁶. 1 Then, 100 μL was evenly added to an LB plate, and photographs and observations were taken. The same *E. coli* and *Staphylococcus aureus* suspensions were used in the blank control group, with the steps identical to the above except that no membrane sample was added. Colony counts were recorded and the inhibition rate was calculated. The formula for calculating the antibacterial rate (R) is as follows:
[0062]
[0063] Where R is the antibacterial rate, A is the number of colonies in the sample containing the membrane, and B is the number of colonies in the blank bacterial solution.
[0064] The experimental results of the reverse osmosis membrane prepared in Example 1 are shown in Table 2.
[0065] Comparative Example 1
[0066] (1) Clean the polysulfone ultrafiltration membrane (molecular weight cutoff 30,000) with pure water and use it as a support layer for later use;
[0067] (2) Preparation of oil phase solution: Prepare an aqueous solution of m-phenylenediamine with a mass fraction of 2.0%;
[0068] (3) Preparation of oil phase solution: Prepare a 0.1% (w / w) solution of pyromellitic methyl chloride and hexane;
[0069] (4) Preparation of aromatic polyamide layer reverse osmosis membrane: Take out the polysulfone-based membrane and fix it on the glass plate. Use an air knife to blow dry the water. Pour the aqueous phase solution onto the surface of the polysulfone-based membrane. After 5 minutes, pour off the excess aqueous phase solution and blow dry with an air knife. Then pour the oil phase solution onto the membrane surface and react for 1 minute. Pour off the excess oil phase solution.
[0070] (5) Place the membrane obtained above in an oven at 60°C and heat treat for 1 hour; remove the membrane and rinse with pure water for later use.
[0071] Figure 1 Scanning electron microscope image of the surface structure of the blank control reverse osmosis membrane prepared for Comparative Example 1.
[0072] Membrane flux and rejection rate testing: The modified reverse osmosis membrane was filtered for 1 hour at 2 MPa and 25°C using a 2000 ppm sodium chloride aqueous solution, and its initial permeate flux and rejection rate were then tested. The membrane flux and sodium chloride rejection rate were calculated using the following formulas.
[0073] Flux = Permeate volume / (Time × Membrane area)
[0074] Retention rate = (Feed solution conductivity - Permeate conductivity) / Feed solution conductivity
[0075] The initial permeation flux and salt rejection rate of the modified membrane were obtained by filtering a 2000ppm sodium chloride aqueous solution at 2MPa and 25℃, as shown in Table 1.
[0076] Antibacterial test: The membrane sample was uniformly dispersed in a diluted solution of *E. coli* or *Staphylococcus aureus*, and the suspension containing the membrane sample was placed in a shaker at 37°C for 3 hours. After contacting the culture with the membrane sample for 3 hours, the bacterial solution was further diluted 10⁻⁶. 1Then, 100 μL was evenly added to an LB plate, and photographs and observations were taken. The same *E. coli* and *Staphylococcus aureus* suspensions were used in the blank control group, with the steps identical to the above except that no membrane sample was added. Colony counts were recorded and the inhibition rate was calculated. The formula for calculating the antibacterial rate (R) is as follows:
[0077]
[0078] Where R is the antibacterial rate, A is the number of colonies in the sample containing the membrane, and B is the number of colonies in the blank bacterial solution.
[0079] The experimental results of the reverse osmosis membrane prepared in Comparative Example 1 are shown in Table 2.
[0080] Table 1. Membrane flux and rejection rate tests:
[0081]
[0082] Table 2 Antibacterial Tests:
[0083]
[0084] Test results show that, compared with the blank control reverse osmosis membrane (Comparative Example 1), the terbinafine-modified antibacterial reverse osmosis membrane prepared by the method of this invention has a significantly increased water flux and excellent antibacterial performance.
Claims
1. A method for preparing a terbinafine-modified antibacterial reverse osmosis membrane, characterized in that, The terbinafine-modified antibacterial reverse osmosis membrane is an aromatic polyamide reverse osmosis membrane, comprising the following steps: (1) Take out the polysulfone membrane and fix it on the plate. Use an air knife to blow dry the water. Pour the aqueous solution onto the surface of the polysulfone membrane. After a period of time, pour off the excess aqueous solution and blow dry it again with an air knife. Then pour the oil solution onto the surface of the base membrane. After a period of time, pour off the excess oil solution to obtain the pre-made aromatic polyamide reverse osmosis membrane. (2) Place the pre-made aromatic polyamide reverse osmosis membrane obtained in step (1) in an oven, heat-treat it for a period of time, and then take it out and clean it to obtain the aromatic polyamide reverse osmosis membrane. (3) The aromatic polyamide reverse osmosis membrane obtained in step (2) is immersed in a mixed solution of glutaraldehyde and sulfuric acid, left to stand for a period of time, then the excess solution is poured off and dried; finally, a 5-20 mg / ml terbinazone solution is poured onto the surface of the reverse osmosis membrane with glutaraldehyde coating; after heat treatment for a certain period of time, it is immersed in deionized water to obtain a terbinazone-modified antibacterial reverse osmosis membrane.
2. The method for preparing the terbinafine-modified antibacterial reverse osmosis membrane according to claim 1, characterized in that, In step (3), the method for preparing the mixed solution of glutaraldehyde and sulfuric acid is as follows: prepare an aqueous solution of glutaraldehyde with a mass fraction of 0.01-0.05% and sulfuric acid with a mass fraction of 0.1-0.5%, and sonicate for a period of time to obtain the mixed solution of glutaraldehyde and sulfuric acid.
3. The method for preparing the terbinafine-modified antibacterial reverse osmosis membrane according to claim 1, characterized in that, In step (3), the settling time is 1-10 minutes.
4. The method for preparing the terbinafine-modified antibacterial reverse osmosis membrane according to claim 1, characterized in that, The terbinafine-modified antibacterial reverse osmosis membrane exhibits antibacterial activity greater than 94% against Escherichia coli and Staphylococcus aureus, and a concentration greater than 75 L / m³. 2 ·h water flux.