A photocatalytic synergistic multi-dimensional electric field composite membrane filtration device

Abstract

The present invention provides a photocatalytic synergistic multi-dimensional electric field composite membrane filtration device, which relates to the technical field of water treatment and includes: a conductive filter element module, which is a hollow cylindrical structure and includes a hollow porous support body and a composite conductive filter membrane covering the outer layer thereof; a photocatalytic ultrafiltration membrane module, which is annularly nested inside the conductive filter element module; the photocatalytic ultrafiltration membrane module is composed of a polyethersulfone-based membrane and a TiO2 / rGO composite photocatalytic layer loaded on its surface; a multi-dimensional electric field electrode system, which includes an axial electrode and a radial electrode array; the axial electrode is a hollow carbon fiber tube nested inside the photocatalytic ultrafiltration membrane module; and the radial electrode array is composed of multiple arc-shaped graphite electrodes surrounding the outer circumference of the conductive filter element module. The present invention can solve the problems of existing electric field filtration in insufficient removal of neutral / macromolecular pollutants, the dependence of photocatalysis on light and low efficiency, and the easy clogging and short life of the membrane of traditional electric field devices.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and in particular to a photocatalytic synergistic multi-dimensional electric field composite membrane filtration device. Background Art

[0002] Among existing water treatment technologies, electric field driven filtration and photocatalysis technologies each play an important role, but both have obvious limitations, as follows:

[0003] Electric field driven filtration technology mainly utilizes the effect of electric field forces on charged particles to achieve pollutant removal. In the electric field, charged pollutant particles will be pulled by the electric field force and move toward the electrode, thereby being intercepted or separated. When treating sewage containing charged particles, this technology can effectively remove charged colloids, microorganisms and other pollutants in the water. Although electric field filtration can adsorb charged particles through the action of charges, it has limited effect on the removal of neutral or large molecular organic matter, making it difficult for the treated water quality to meet higher standards. In addition, traditional electric field filtration devices are mostly single-layer or double-layer electric field structures with a single electric field distribution, which can easily lead to the accumulation of impurities on the membrane surface and shorten the membrane life.

[0004] Photocatalytic technology relies on the photogenerated electron-hole pairs produced by photocatalysts under illumination. These electrons and holes possess strong redox properties, reacting with pollutants in water, breaking them down into carbon dioxide, water, and other harmless small molecules. This technology eliminates the need for adding large amounts of chemical reagents to treat organic pollutants, achieving mineralization and degradation. While photocatalytic technology can decompose pollutants solely under illumination, its reaction efficiency is limited by the availability of light energy and the activity of the catalyst, making it difficult to guarantee sustained and efficient treatment results. Summary of the Invention

[0005] The problems solved by the present invention are that the existing electric field filtration is insufficient in removing neutral / macromolecular pollutants, photocatalysis is dependent on light and has low efficiency, and the membrane of the traditional electric field device is easily clogged and has a short lifespan.

[0006] To solve the above problems, the present invention provides a photocatalytic synergistic multi-dimensional electric field composite membrane filtration device, comprising:

[0007] The conductive filter element module is a hollow cylindrical structure, comprising a hollow porous support and a composite conductive filter membrane coated on the outer layer of the hollow porous support;

[0008] The photocatalytic ultrafiltration membrane module is annularly nested inside the conductive filter element module; the photocatalytic ultrafiltration membrane module is composed of a polyethersulfone base membrane and a TiO2 / rGO composite photocatalytic layer loaded on the surface of the polyethersulfone base membrane;

[0009] A multi-dimensional electric field electrode system comprising an axial electrode and a radial electrode array; the axial electrode is a hollow carbon fiber tube with micropores on its surface nested inside the photocatalytic ultrafiltration membrane module; the radial electrode array is composed of multiple arc-shaped graphite electrodes surrounding the outer periphery of the conductive filter module, with the spacing between the multiple arc-shaped graphite electrodes adjustable within a range of 10 to 20 cm; and

[0010] The intelligent control module is used to measure the real-time water quality and dynamically adjust the electric field strength, electrode polarity and lighting parameters according to the real-time water quality.

[0011] Optionally, the intelligent control module includes a water quality sensor, an adjustable power supply and an ultraviolet light source; the water quality sensor is located at the water inlet and the water outlet, and the ultraviolet light source is evenly distributed around the outside of the photocatalytic ultrafiltration membrane module.

[0012] Optionally, the axial electrode is connected to the positive pole of the adjustable power supply, the radial electrode array is connected to the variable positive / negative pole of the adjustable power supply in different regions, and the photocatalytic ultrafiltration membrane module is connected to the negative pole of the adjustable power supply; the frequency of the adjustable power supply in the pulse output mode is 10 to 100 Hz.

[0013] Optionally, the distance between the ultraviolet light source and the surface of the photocatalytic ultrafiltration membrane module is 3 to 7 cm.

[0014] Optionally, the hollow porous support is a hollow cylinder made of polypropylene, the diameter of the pores in the middle of the hollow porous support is 10 to 50 μm, and the porosity is ≥70%.

[0015] Optionally, the composite conductive filter membrane has a thickness of 50 to 100 μm.

[0016] Optionally, the polyethersulfone-based membrane has a molecular weight cut-off of 10 kDa and a pore size of 0.1 to 0.5 μm.

[0017] Optionally, the micropores have a pore diameter of 5 μm to 15 μm and a pore density of 90 to 100 pores / cm².

[0018] Optionally, the manufacturing method of the conductive filter element module includes the following steps:

[0019] The hollow porous support is immersed in anhydrous ethanol and ultrasonically cleaned for 20 to 40 minutes; then rinsed with deionized water, and vacuum dried at 50 to 70° C. for 1 to 3 hours to obtain a pretreated hollow porous support;

[0020] Take 1 mol / L hydrochloric acid solution, add aniline monomer to make the concentration of aniline monomer 4 to 6 g / mL, and stir magnetically until completely dissolved;

[0021] A 2 mg / mL graphene oxide dispersion containing 50% of the volume of a hydrochloric acid solution was added to the above solution, and ultrasonic treatment was performed to uniformly disperse the graphene oxide to form an aniline-graphene oxide mixed solution; the pretreated hollow porous support was immersed in the aniline-graphene oxide mixed solution;

[0022] Slowly adding an ammonium persulfate solution dropwise to the aniline-graphene oxide mixed solution in an ice-water bath at 0 to 5°C to initiate aniline polymerization; continuing the reaction for 5 to 7 hours while maintaining a stirring speed of 160 to 240 rpm to form a composite conductive layer on the surface of the hollow porous support;

[0023] The hollow porous support was taken out, rinsed with deionized water, and then immersed in a 0.1 mol / L NaOH solution for 5 to 15 minutes, and finally dried under vacuum conditions at 50 to 70° C. to obtain a hollow porous support with a surface coated with a graphene / polyaniline composite conductive filter membrane.

[0024] Optionally, the method for manufacturing the photocatalytic ultrafiltration membrane module comprises the following steps:

[0025] The polyethersulfone base membrane is immersed in deionized water and ultrasonically cleaned; rinsed with anhydrous ethanol, and vacuum-dried at 30 to 50° C. for later use to obtain a pretreated polyethersulfone base membrane;

[0026] Tetrabutyl titanate was added dropwise to anhydrous ethanol to a volume fraction of 20 to 30% of tetrabutyl titanate, and magnetic stirring was performed for 20-30 minutes. Then, glacial acetic acid (50% by volume of tetrabutyl titanate) was added and stirring was continued until the solution was clear. Deionized water was then added dropwise until a transparent TiO2 sol was formed.

[0027] A graphene oxide dispersion twice the volume of tetrabutyl titanate is added to the TiO2 sol; ultrasonic treatment is performed for 1 to 3 hours, and hexadecyltrimethylammonium bromide is added to a concentration of 1 to 2 g / L, and stirred for 1 to 3 hours to form a TiO2 / rGO composite sol;

[0028] The pretreated polyethersulfone base membrane is fixed on a dip coating machine bracket, and the polyethersulfone base membrane is immersed in the TiO2 / rGO composite sol at a speed of 0.3 to 0.7 cm / s. After staying for 8 to 12 seconds, it is pulled up at a constant speed to form a uniform coating; the dip coating is repeated multiple times, and each layer is dried at room temperature after coating to obtain a coated polyethersulfone base membrane;

[0029] The coated polyethersulfone-based membrane was placed in a UV curing box and irradiated with 365nm UV light for 20 to 40 minutes; the cured polyethersulfone-based membrane was immersed in a 0.1mol / L NaOH solution for 8 to 12 minutes; the membrane was rinsed with deionized water and vacuum dried at 30 to 50°C to obtain a polyethersulfone-based membrane loaded with a TiO2 / rGO composite photocatalytic layer.

[0030] The beneficial effects of the photocatalytic synergistic multi-dimensional electric field composite membrane filtration device of the present invention are: organically combining electric field adsorption, photocatalytic degradation and membrane separation technology, and realizing efficient removal of pollutants and long-term operation of the system through modular innovative design. The conductive filter element cooperates with the multi-dimensional electrode system to form a dynamic cross electric field, which can effectively remove charged and neutral pollutants; the photocatalytic ultrafiltration membrane module decomposes large molecular organic matter through the composite photocatalytic layer, and realizes the membrane self-cleaning function, reducing the need for chemical cleaning. The intelligent control module can adjust the electric field strength, electrode polarity and light parameters in real time according to the water quality to ensure that the system is always in an efficient operating state. The structural optimization of each component of the device effectively reduces membrane pollution, improves the uniformity of water flow distribution, and greatly reduces energy consumption and maintenance costs. It can be widely used in scenarios such as industrial wastewater treatment and drinking water purification. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a structural schematic diagram of a photocatalytic synergistic multi-dimensional electric field composite membrane filtration device.

[0032] Description of reference numerals:

[0033] 1. Conductive filter element module; 1a. Composite conductive filter membrane; 1b. Hollow porous support; 2. Photocatalytic ultrafiltration membrane module; 2a. Polyethersulfone-based membrane; 2b. TiO2 / rGO composite photocatalytic layer; 3. Axial electrode; 3a. Micropores; 4. Radial electrode array; 5. Intelligent control module; 6. Water inlet; 7. Water outlet. DETAILED DESCRIPTION

[0034] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0035] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to"; the term "based on" means "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0036] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0037] like Figure 1 As shown, this embodiment provides a photocatalytic synergistic multi-dimensional electric field composite membrane filtration device, including a cylindrical shell and the following components arranged in the shell:

[0038] The conductive filter element module 1 is a hollow cylindrical structure, comprising a hollow porous support 1b and a composite conductive filter membrane 1a coated on the outer layer of the hollow porous support 1b;

[0039] The photocatalytic ultrafiltration membrane module 2 is annularly nested inside the conductive filter element module 1 and is composed of a polyethersulfone base membrane 2a and a TiO2 / rGO composite photocatalytic layer 2b loaded on the surface of the polyethersulfone base membrane 2a;

[0040] The multi-dimensional electric field electrode system includes an axial electrode 3 and a radial electrode array. The axial electrode 3 is a hollow carbon fiber tube nested inside the photocatalytic ultrafiltration membrane module 2, with micropores 3a on its surface. The radial electrode array 4 is composed of multiple arc-shaped graphite electrodes surrounding the outer periphery of the conductive filter module 1. The spacing between the multiple arc-shaped graphite electrodes can be adjusted within a range of 10 to 20 cm.

[0041] The intelligent control module 5 is used to measure the real-time water quality and dynamically adjust the electric field strength, electrode polarity and illumination parameters according to the real-time water quality;

[0042] The middle of the side of the shell is provided with a water inlet 6 and the bottom is provided with a water outlet 7. There can be multiple water inlets 6, evenly arranged outside the shell. The axis of the photocatalytic ultrafiltration membrane module 2 coincides with the axis of the hollow porous support 1b.

[0043] In this embodiment, a significant performance breakthrough is achieved through the collaborative design of multiple components: the composite conductive filter membrane is coordinated with the multi-dimensional electric field electrode system, and the axial main electric field and the radial dynamic cross electric field are utilized, combined with the dielectrophoresis effect to efficiently remove charged and neutral pollutants. At the same time, the TiO2 / rGO composite photocatalytic layer in the photocatalytic ultrafiltration membrane module decomposes large molecular organic matter; the adjustable characteristics of the radial electrode array avoid local accumulation of pollutants on the membrane surface, and the self-cleaning function of the photocatalytic layer further reduces membrane pollution and extends the service life of the membrane; the intelligent control module monitors the water quality in real time and dynamically adjusts the electric field strength, electrode polarity and light parameters to ensure that the device can operate efficiently under different water quality and light conditions; in addition, the structural design of the hollow porous support body, spiral guide groove and other structural designs optimizes the mass transfer efficiency, and the durable materials ensure long-term stable operation, making it widely applicable to various complex water quality treatment scenarios.

[0044] The device of the present invention achieves efficient pollutant removal and membrane performance optimization through the synergistic effect of multi-dimensional electric fields and photocatalysis: the DOC (Dissolved Organic Carbon) removal rate exceeds 90%, COD (Chemical Oxygen Demand) is reduced to below 15 mg / L, and the microbial retention rate reaches more than 99.9%, significantly improving the water purification effect; the membrane operating pressure fluctuation is reduced by 40%, and the cleaning cycle is extended to twice that of traditional devices, effectively reducing membrane pollution and maintenance costs; the overall energy consumption is reduced by 30%, and it is suitable for deep treatment scenarios of highly polluted industrial wastewater and drinking water, combining high efficiency, economy and wide applicability.

[0045] Specifically, the intelligent control module 5 includes a water quality sensor, an adjustable power supply and an LED ultraviolet light source; the water quality sensors are located at the water inlet and the water outlet. The water quality sensor at the water inlet is located at the front end of the water inlet pipe and is used to monitor the raw water quality parameters (such as COD, TOC, turbidity, pH value, conductivity, etc.) in real time. The water quality sensor at the water outlet is located at the purified water outlet and is used to verify that the final water quality meets the standards.

[0046] Specifically, the axial electrode 3 is connected to the positive electrode, the radial electrode array 4 is connected to the variable positive / negative electrode in different regions, and the photocatalytic ultrafiltration membrane module 2 is connected to the negative electrode.

[0047] Specifically, the ultraviolet light sources are evenly distributed around the outer side of the photocatalytic ultrafiltration membrane module 2; and the frequency of the adjustable power supply in the pulse output mode is 10 to 100 Hz.

[0048] Specifically, the distance between the ultraviolet light source and the surface of the photocatalytic ultrafiltration membrane module 2 is 3 to 7 cm.

[0049] The water quality sensor primarily detects water quality parameters such as COD, TOC, turbidity, pH, and conductivity. Intelligent control module 5 dynamically adjusts the electric field strength, electrode polarity, and illumination parameters based on real-time water quality as follows: For every 20 mg / L increase in COD, the axial electric field strength increases by 1 V / cm. When TOC is greater than 10 mg / L, the UV light intensity increases from 30 mW / cm² to 50 mW / cm². If TOC is less than 5 mg / L and turbidity is less than 1 NTU, the UV light is turned off. When conductivity is greater than 3 mS / cm, pulse mode (10 to 100 Hz) is activated, with the positive and negative polarity switching every 5 minutes. When the pH is less than 4 or greater than 10, the UV light source is turned off.

[0050] In this embodiment, the intelligent control module 5 utilizes water quality sensors installed at the water inlet and outlet to monitor key parameters of both raw and purified water in real time, including COD, TOC, turbidity, pH, and conductivity. Based on pre-set rules, it dynamically adjusts the electric field intensity, electrode polarity, and illumination parameters. This multi-parameter intelligent control mechanism not only enables adaptive processing of complex water quality, avoiding energy waste, but also significantly improves pollutant removal efficiency and extends the life of the membrane modules by precisely matching the electric field with photocatalytic conditions, ensuring stable and efficient operation of the device under diverse operating conditions.

[0051] The present invention uses a stable main electric field to adsorb charged pollutants, a dynamic cross-electric field dielectrophoresis to capture neutral pollutants, and uses the electric field and photocatalysis to synergistically optimize the distribution of pollutants on the membrane surface and achieve self-cleaning, thereby significantly improving the device's removal efficiency for all types of pollutants and the long-term stability of membrane performance.

[0052] Specifically, the hollow porous support body 1b is a hollow cylinder made of polypropylene, the pore size of the pore in the middle of the hollow porous support body (1b) is 10 to 50 μm, and the porosity is ≥70%.

[0053] Specifically, the thickness of the composite conductive filter membrane 1a is 50 to 100 μm.

[0054] Specifically, the polyethersulfone-based membrane 2a has a molecular weight cut-off of 10 kDa and a pore size of 0.1 to 0.5 μm.

[0055] Specifically, the micropores 3a have a pore diameter of 5 μm to 15 μm and a pore density of 90 to 100 pores / cm².

[0056] In this embodiment, the thickness of the composite conductive filter membrane can maintain a high ion conduction efficiency while ensuring mechanical strength, avoiding the risk of increased resistance due to excessive thickness or damage due to excessive thinness; the polyethersulfone-based membrane can accurately intercept large molecular pollutants (such as proteins and colloids) with a molecular weight greater than 10kDa, and can also reduce membrane filtration resistance through a larger pore size, thereby increasing water flux; the axial electrode micropores can ensure uniform water flow while providing sufficient migration channels for charged pollutants, enhancing the electric field adsorption effect, and the dense and uniform distribution of micropores can optimize the electric field distribution, reduce local eddy currents, and improve overall filtration efficiency and stability.

[0057] Optionally, the manufacturing method of the conductive filter element module 1 includes the following steps:

[0058] The hollow porous support 1b was immersed in anhydrous ethanol and ultrasonically cleaned for 30 minutes to remove surface impurities; then rinsed with deionized water three times and vacuum dried at 60°C for 2 hours for later use;

[0059] Take 100 mL of 1 mol / L hydrochloric acid solution, add 5 g of aniline monomer, and stir magnetically until completely dissolved;

[0060] Add 50 mL of 2 mg / mL graphene oxide dispersion to the above solution and sonicate for 2 hours to uniformly disperse the GO to form an aniline-GO mixed solution. Immerse the pretreated hollow porous support 1b in the aniline-GO mixed solution to ensure complete immersion.

[0061] In an ice-water bath at 0 to 5°C, ammonium persulfate solution (APS:aniline molar ratio = 1:1) was slowly added dropwise to initiate aniline polymerization. The reaction was continued for 6 hours with a stirring speed of 200 rpm to allow polyaniline (PANI) and GO to copolymerize on the support surface, forming a composite conductive layer.

[0062] The hollow porous support 1b was taken out and rinsed with deionized water three times to remove unreacted monomers and impurities. The sample was then immersed in a 0.1 mol / L NaOH solution for 10 minutes to neutralize the residual hydrochloric acid. Finally, it was dried under vacuum conditions at 60°C for 4 hours to obtain a hollow porous support 1b with a surface-coated graphene / polyaniline composite conductive filter membrane 1a. The thickness of the graphene / polyaniline composite conductive filter membrane 1a was 50 μm to 100 μm.

[0063] In this embodiment, the manufacturing method of the conductive filter element module achieves performance optimization through a multi-step process. Through the precise control of process parameters, a firm bond between the composite conductive filter membrane and the support body and a balance between conductive performance and mechanical strength are achieved, providing an efficient and stable electric field conduction foundation for the device.

[0064] Optionally, the manufacturing method of the photocatalytic ultrafiltration membrane module 2 includes the following steps:

[0065] Soak the polyethersulfone base membrane 2a in deionized water and ultrasonically clean it for 20 minutes to remove surface impurities; rinse it with anhydrous ethanol 3-5 times, and vacuum dry it at 40°C for 1 hour for later use;

[0066] Slowly add 10 mL of tetrabutyl titanate (TBOT) dropwise to 40 mL of anhydrous ethanol and stir magnetically for 20-30 minutes. Then add 5 mL of glacial acetic acid as a stabilizer and continue stirring until the solution is clear. Then, add 10 mL of deionized water dropwise (control the dropwise addition rate at 1 mL / min) to form a transparent TiO2 sol.

[0067] 20 mL of graphene oxide dispersion (GO concentration 2 mg / mL) was added to the TiO2 sol. Ultrasonic treatment was performed for 2 hours to uniformly disperse the GO and bind it to the TiO2 nanoparticles. 0.1 g of hexadecyltrimethylammonium bromide (CTAB) was added as a surfactant and stirred for 2 hours to form a TiO2 / rGO composite sol.

[0068] The pretreated polyethersulfone base membrane 2a is fixed on the dip coating machine bracket, and the polyethersulfone base membrane (2a) is immersed in the composite sol at a speed of 0.5 cm / s, and then pulled up at a constant speed after staying for 10 seconds to form a uniform coating; the dipping is repeated 3 times, and each layer is dried at room temperature for 10 minutes after coating;

[0069] The coated polyethersulfone-based membrane (2a) was placed in a UV curing box and irradiated with 365nm UV light for 30 minutes (light intensity 30W / cm²); the cured polyethersulfone-based membrane (2a) was immersed in a 0.1mol / L NaOH solution for 10 minutes to remove residual surfactant; it was rinsed with deionized water three times and vacuum dried at 40°C for 2 hours to obtain a polyethersulfone-based membrane (2a) loaded with a TiO2 / rGO composite photocatalytic layer (2b).

[0070] In this embodiment, the manufacturing method of the photocatalytic ultrafiltration membrane module 2 achieves performance optimization through a multi-step process. Through the precise control of process parameters, a firm combination of the TiO2 / rGO composite photocatalytic layer and the polyethersulfone-based membrane is achieved, thereby optimizing the synergistic effect of photocatalytic activity and membrane separation performance, and providing the device with efficient and stable pollutant degradation and separation capabilities.

[0071] Optionally, the manufacturing method of the axial electrode 3 includes the following steps: soaking the hollow carbon fiber tube in acetone and ultrasonically cleaning it for 30 minutes to remove surface contaminants. After rinsing with deionized water, vacuum drying is performed at 80°C for 2 hours. Using an ultraviolet laser puncher (wavelength 355nm, power 30W), uniformly punch holes on the surface of the carbon fiber tube, with a pore size of 5 to 15μm and a pore density of 100 holes / cm². After punching, ultrasonic cleaning is performed again to remove residual carbon debris. Conductive silver glue is applied to the inner wall of each end of the carbon fiber tube and connected to a copper wire (diameter 2mm). After curing, the resistance is ≤0.1Ω. The hollow carbon fiber tube is nested inside the photocatalytic ultrafiltration membrane module and secured with a sealing ring to prevent water leakage.

[0072] The radial electrode array 4 manufacturing method includes the following steps: the radius of the curved graphite electrodes matches the outer diameter of the conductive filter element. A copper guide is welded to the back of each electrode to support independent voltage control in each zone. The electrodes are placed around the conductive filter module with a spacing of 10 to 20 cm. The power supply is connected via a waterproof junction box.

[0073] In this embodiment, the axial electrode achieves a clean surface, uniform pores and excellent conductive performance through precise control of process parameters, and the nested fixed design ensures sealing; the radial electrode achieves dynamic adjustment of the electric field direction and stable power supply through precise control of process parameters. Both processes improve the uniformity of electric field distribution, electrode conductivity and overall reliability of the device through material processing and structural optimization, providing an efficient and stable electric field foundation for multi-dimensional electric field synergistic photocatalysis.

[0074] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A photocatalytic synergistic multi-dimensional electric field composite membrane filtration device, characterized in that: include: The conductive filter element module (1) is a hollow cylindrical structure, comprising a hollow porous support body (1b) and a composite conductive filter membrane (1a) coated on the outer layer of the hollow porous support body (1b); A photocatalytic ultrafiltration membrane module (2) is annularly nested inside the conductive filter element module (1); the photocatalytic ultrafiltration membrane module (2) is composed of a polyethersulfone-based membrane (2a) and a TiO2 / rGO composite photocatalytic layer (2b) loaded on the surface of the polyethersulfone-based membrane (2a); A multi-dimensional electric field electrode system comprises an axial electrode (3) and a radial electrode array (4); the axial electrode (3) is a hollow carbon fiber tube embedded inside the photocatalytic ultrafiltration membrane module (2), and has micropores (3a) on its surface; the radial electrode array (4) is composed of a plurality of arc-shaped graphite electrodes surrounding the outer periphery of the conductive filter element module (1), and the spacing between the plurality of arc-shaped graphite electrodes is adjustable within a range of 10 to 20 cm; as well as The intelligent control module (5) is used to measure the real-time water quality and dynamically adjust the electric field intensity, electrode polarity and illumination parameters according to the real-time water quality.

2. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The intelligent control module (5) comprises a water quality sensor, an adjustable power supply and an ultraviolet light source; the water quality sensor is located at the water inlet and the water outlet, and the ultraviolet light source is evenly distributed around the outside of the photocatalytic ultrafiltration membrane module (2).

3. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 2, characterized in that: The axial electrode (3) is connected to the positive pole of the adjustable power supply, the radial electrode array (4) is connected to the variable positive / negative poles of the adjustable power supply in different regions, and the photocatalytic ultrafiltration membrane module (2) is connected to the negative pole of the adjustable power supply; the frequency of the adjustable power supply in the pulse output mode is 10 to 100 Hz.

4. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 2, characterized in that: The distance between the ultraviolet light source and the surface of the photocatalytic ultrafiltration membrane module (2) is 3 to 7 cm.

5. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The hollow porous support (1b) is a hollow cylinder made of polypropylene. The pores in the middle of the hollow porous support (1b) have a pore diameter of 10 to 50 μm and a porosity of ≥70%.

6. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The thickness of the composite conductive filter membrane (1a) is 50 to 100 μm.

7. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The polyethersulfone-based membrane (2a) has a molecular weight cut-off of 10 kDa and a pore size of 0.1 to 0.5 μm.

8. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The micropores (3a) have a pore diameter of 5 μm to 15 μm and a pore density of 90 to 100 pores / cm².

9. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The manufacturing method of the conductive filter element module (1) comprises the following steps: The hollow porous support (1b) is immersed in anhydrous ethanol and ultrasonically cleaned for 20 to 40 minutes; then rinsed with deionized water, and vacuum dried at 50 to 70° C. for 1 to 3 hours for use, thereby obtaining a pretreated hollow porous support (1b); Take 1 mol / L hydrochloric acid solution, add aniline monomer to make the concentration of aniline monomer 4 to 6 g / mL, and stir magnetically until completely dissolved; Adding 2 mg / mL graphene oxide dispersion in a volume of 50% of the hydrochloric acid solution to the above solution, and performing ultrasonic treatment to uniformly disperse the graphene oxide to form an aniline-graphene oxide mixed solution; immersing the pretreated hollow porous support (1b) in the aniline-graphene oxide mixed solution; Slowly adding an ammonium persulfate solution to the aniline-graphene oxide mixed solution in an ice-water bath at 0 to 5° C. to initiate an aniline polymerization reaction; continuing the reaction for 5 to 7 hours while maintaining a stirring speed of 160 to 240 rpm to form a composite conductive layer on the surface of the hollow porous support (1b); The hollow porous support (1b) is taken out and rinsed with deionized water. The hollow porous support (1b) is then immersed in a 0.1 mol / L NaOH solution for 5 to 15 minutes. Finally, the hollow porous support (1b) is dried under vacuum conditions at 50 to 70° C. to obtain a hollow porous support (1b) having a surface coated with a graphene / polyaniline composite conductive filter membrane (1a).

10. The photocatalytic synergistic multi-dimensional electric field composite membrane filtration device according to claim 1, characterized in that: The manufacturing method of the photocatalytic ultrafiltration membrane module (2) comprises the following steps: The polyethersulfone-based membrane (2a) is immersed in deionized water and ultrasonically cleaned; rinsed with anhydrous ethanol, and vacuum-dried at 30 to 50° C. for later use, thereby obtaining a pretreated polyethersulfone-based membrane (2a); Tetrabutyl titanate was added dropwise to anhydrous ethanol to a volume fraction of 20 to 30% by volume of the tetrabutyl titanate, and magnetic stirring was performed for 20-30 minutes; glacial acetic acid (50% by volume of the tetrabutyl titanate) was then added, and stirring was continued until the solution was clear; deionized water was then added dropwise until a transparent TiO2 sol was formed; A graphene oxide dispersion having a volume twice that of the tetrabutyl titanate is added to the TiO2 sol; ultrasonic treatment is performed for 1 to 3 hours, and hexadecyltrimethylammonium bromide is added to a concentration of 1 to 2 g / L, and stirred for 1 to 3 hours to form a TiO2 / rGO composite sol; Fixing the pretreated polyethersulfone-based membrane (2a) on a dip-coating machine support, dipping the polyethersulfone-based membrane (2a) into the TiO2 / rGO composite sol at a speed of 0.3 to 0.7 cm / s, holding for 8 to 12 seconds, and then pulling at a constant speed to form a uniform coating; repeating the dipping process multiple times, drying each layer at room temperature after coating, to obtain a coated polyethersulfone-based membrane (2a); The coated polyethersulfone-based membrane (2a) is placed in a UV curing box and irradiated with 365nm UV light for 20 to 40 minutes; the cured polyethersulfone-based membrane (2a) is immersed in a 0.1mol / L NaOH solution for 8 to 12 minutes; the membrane is rinsed with deionized water and vacuum-dried at 30 to 50°C to obtain a polyethersulfone-based membrane (2a) loaded with a TiO2 / rGO composite photocatalytic layer (2b).

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