Multilayer antimicrobial superhydrophobic membrane

Abstract

The utility model relates to a kind of multilayer antibacterial super-hydrophobic membrane, belong to membrane material technical field, including the fiber braided tube of supporting effect, the upper surface of fiber braided tube is high-temperature consolidation and has flat plate film, the upper surface of flat plate film is attached with antibacterial particle and forms antibacterial layer, antibacterial layer is coated with low surface energy modifier and forms super-hydrophobic layer located in top layer, the multilayer antibacterial super-hydrophobic membrane solves the flux low of traditional hydrophobic membrane and faces serious membrane pollution and membrane infiltration etc., can be applied in the process of other industrial wastewater such as desulfurization wastewater and pure water.

Description

Technical Field

[0001] This utility model relates to a multilayer antibacterial superhydrophobic membrane, belonging to the field of membrane material technology. Background Technology

[0002] Seawater desalination is currently a relatively effective way to solve the shortage of freshwater. Among many technologies, membrane distillation technology uses the vapor pressure difference across the membrane as a driving force to allow water vapor to pass through the membrane material for desalination. It can also utilize low-grade heat energy such as high-concentration, highly polluted brine and industrial waste heat to improve the resource utilization rate of wastewater. However, traditional hydrophobic membranes have low flux and face serious problems such as membrane fouling and membrane wetting, which seriously limit the further development of membrane distillation technology.

[0003] Polytetrafluoroethylene (PTFE) membrane materials are prone to fouling after prolonged immersion in seawater, leading to wetting failure. Current commercial membrane modules generally employ periodic cleaning to mitigate fouling, but this method cannot completely reverse the problem and significantly reduces the membrane material's lifespan. Therefore, it is necessary to improve the antifouling performance of membrane materials from the material itself. However, seawater pollutants are complex in composition, and traditional antifouling modifications have short effective periods. Thus, it is essential to explore and develop novel antifouling technologies targeting the membrane material itself. Utility Model Content

[0004] To address the aforementioned problems in existing technologies, this invention provides a multilayer antibacterial superhydrophobic membrane with antibacterial properties and a superhydrophobic surface, thereby extending its service life in practical applications.

[0005] The technical solution of this utility model is as follows:

[0006] One of the objectives of this invention is to provide a multilayer antibacterial superhydrophobic membrane, comprising a fiber braided tube that provides support, a flat sheet membrane that is solidified at high temperature on the upper surface of the fiber braided tube, antibacterial particles that are attached to the upper surface of the flat sheet membrane to form an antibacterial layer, and a low surface energy modifier that is coated on the antibacterial layer to form a superhydrophobic layer on the top layer.

[0007] Furthermore, the thickness of the multilayer antibacterial superhydrophobic membrane is 0.2-0.3 mm.

[0008] Furthermore, the fiber braided tube is one of glass fiber braided tube, polylactic acid fiber braided tube, or polyester fiber braided tube.

[0009] Furthermore, the thickness of the fiber braided tube is 0.1-0.2 mm.

[0010] Furthermore, the flat sheet membrane is made of either polyvinylidene fluoride or polytetrafluoroethylene, with a pore size of 0.1-0.5 μm and a thickness of 0.05-0.1 mm.

[0011] Furthermore, the antibacterial particles are silver nanoparticles encapsulated in silica.

[0012] Furthermore, the superhydrophobic layer is a fluorosilane coupling agent.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] 1. This utility model tightly wraps a soft and poorly supportive flat sheet membrane onto the outer surface of a fiber braided tube with good structural strength. This design makes up for the limitation of insufficient rigidity of the flat sheet membrane material itself. In this way, not only can the technical difficulties of flat sheet membrane module packaging be overcome, but the creep resistance and overall mechanical strength of the membrane material are also significantly improved. In practical applications, it can resist water flow impact and fluctuation, thus broadening the application scenarios.

[0015] 2. This utility model uses silica-encapsulated silver nanoparticles as the core component of the antibacterial layer. Utilizing the slow-release mechanism of silver ions, the silver ions are continuously and slowly released, providing long-lasting antibacterial efficacy. Furthermore, the application uses a fluorosilane coupling agent as a superhydrophobic layer. This agent can form a low surface energy surface, constructing a superhydrophobic barrier on the surface of the membrane material. This greatly reduces the wetting problem of the membrane material during application, giving the membrane material both antibacterial and hydrophobic effects, and improving the material's durability and self-cleaning ability.

[0016] 3. This utility model constructs a high-performance membrane material that integrates support, filtration, antibacterial properties and superhydrophobicity, and is suitable for various specific working conditions and durability application environments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] The reference numerals in the figure are as follows:

[0019] 1. Fiber braided tube; 2. Flat sheet membrane; 3. Antibacterial layer; 4. Superhydrophobic layer. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0021] Please see Figure 1 This utility model discloses a multilayer antibacterial superhydrophobic membrane, comprising a fiber braided tube 1, a flat sheet membrane 2, an antibacterial layer 3, and a superhydrophobic layer 4, which are sequentially stacked from bottom to top. The fiber braided tube 1 serves as the bottom layer for support, and the flat sheet membrane 2 is placed on top of it. The flat sheet membrane 2 and the fiber braided tube 1 are fixedly connected by high-temperature sintering. Antibacterial particles are attached to the surface of the flat sheet membrane 2 to form the antibacterial layer 3 in the middle layer. A low surface energy modifier is coated on the surface of the antibacterial layer 3 to form the superhydrophobic layer 4 in the top layer.

[0022] In this embodiment, the fiber braided tube 1 serves as the structural support material and can be made of glass fiber, polylactic acid fiber, or polyester fiber. It undergoes alkalization treatment to optimize surface properties, followed by thorough rinsing and drying to ensure the purity and durability of the material. The large pore size of the fiber braided tube 1 has minimal impact on the flux of the subsequent membrane material, and the thickness of the fiber braided tube 1 is controlled at 0.1-0.2 mm, which ensures sufficient mechanical strength without compromising the overall lightweight design.

[0023] In this embodiment, the flat sheet membrane 2 is made of high-performance materials such as polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE). These materials have chemical stability and microporous structure with a pore size of 0.1-0.5 μm. The thickness of the flat sheet membrane 2 is 0.05-0.1 mm, so as to achieve effective filtration of small particles while maintaining good fluid permeability.

[0024] In this embodiment, silica-coated silver nanoparticles are used as an antibacterial medium, uniformly distributed on the surface of the flat sheet membrane 2. This not only enhances the antibacterial efficacy of the membrane and effectively inhibits the growth of microorganisms, but the silica shell also provides some protection for silver ions, extending its antibacterial activity period.

[0025] In this embodiment, the top layer is a superhydrophobic layer 4, which is surface modified using a fluorosilane coupling agent. This significantly reduces the surface energy of the material, giving the membrane a superhydrophobic surface. By coating the surface of the antibacterial layer 3 with a fluorosilane coupling agent, not only can the hydrophobicity and antifouling properties of the membrane material be improved, but the service life of the membrane material during long-term operation can also be extended.

[0026] The working principle of this utility model:

[0027] The combination of a multilayer antibacterial superhydrophobic membrane and a membrane distillation system achieves water purification. During operation, the raw water sample first enters a reinforced fiber braided tube 1. This tube, with its excellent support properties, not only provides a stable support platform for the subsequent flat sheet membrane 2 but also ensures smooth water flow. The large pore size of the fiber braided tube 1 avoids limitations on the membrane material's permeability, ensuring sufficient water vapor can pass through efficiently per unit time without compromising overall treatment efficiency. Next, the water flows to the flat sheet membrane 2 for filtration. The membrane effectively isolates and removes various ions from the water, improving water purity. The surface of the membrane 2 is coated with an antibacterial layer 3 and a superhydrophobic layer 4. The antibacterial layer 3 effectively inhibits microbial growth and prevents membrane fouling, while the superhydrophobic layer 4 promotes the rapid sliding of water droplets off the membrane surface, reducing liquid adhesion and retention, thereby enhancing the continuous purification capacity and efficiency of the multilayer antibacterial superhydrophobic membrane. This multilayer antibacterial superhydrophobic membrane can be applied to various water purification scenarios such as seawater desalination, desulfurization wastewater, and oilfield produced water, which is a further development of membrane distillation technology.

[0028] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A multilayer antibacterial superhydrophobic membrane, characterized in that: It includes a fiber braided tube (1) that provides support, a flat sheet membrane (2) that is solidified at high temperature on the upper surface of the fiber braided tube (1), antibacterial particles that are attached to the upper surface of the flat sheet membrane (2) to form an antibacterial layer (3), and a low surface energy modifier that is coated on the antibacterial layer (3) to form a superhydrophobic layer (4) on the top layer.

2. The multilayer antibacterial superhydrophobic membrane as described in claim 1, characterized in that: The thickness of the multilayer antibacterial superhydrophobic membrane is 0.2-0.3 mm.

3. The multilayer antibacterial superhydrophobic membrane as described in claim 1, characterized in that: The fiber braided tube is one of glass fiber braided tube, polylactic acid fiber braided tube, or polyester fiber braided tube.

4. The multilayer antibacterial superhydrophobic membrane as described in claim 3, characterized in that: The thickness of the fiber braided tube (1) is 0.1-0.2 mm.

5. The multilayer antibacterial superhydrophobic membrane as described in claim 1, characterized in that: The flat sheet membrane (2) is made of either polyvinylidene fluoride or polytetrafluoroethylene, with a pore size of 0.1-0.5 μm and a thickness of 0.05-0.1 mm.

6. The multilayer antibacterial superhydrophobic membrane as described in claim 1, characterized in that: The antibacterial particles are silver nanoparticles encapsulated in silica.

7. The multilayer antibacterial superhydrophobic membrane as described in claim 1, characterized in that: The superhydrophobic layer (4) is a fluorosilane coupling agent.

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