A Cu2O / MXene-PVDF self-cleaning hybrid membrane, its preparation method, and its application.

Abstract

This invention discloses a Cu2O / MXene-PVDF self-cleaning hybrid membrane, its preparation method, and its applications. The membrane preparation method includes: adding copper salt and a reducing agent to an MXene material solution and then ultrasonically dispersing the mixture to obtain a mixed solution; heating the solution to obtain a Cu2O / MXene composite material; mixing the Cu2O / MXene composite material, a polymer, and a surfactant uniformly, and reacting to obtain the Cu2O / MXene-PVDF self-cleaning hybrid membrane. In other words, this invention enhances the redox properties of the material by constructing stable cuprous oxide nanoparticles on the surface of MXene sheets; then, through hybridization with an organic polymer and an inorganic catalyst, the susceptibility of MXene to oxidation is suppressed. Through the synergistic effect of oxidation and membrane separation, the irreversible fouling ratio of the membrane is reduced, the flux recovery capacity is improved, and the self-cleaning effect of the membrane is achieved.

Description

Technical Field

[0001] This invention belongs to the field of membrane treatment technology, specifically relating to a Cu2O / MXene-PVDF self-cleaning hybrid membrane, its preparation method, and its application. Background Technology

[0002] Pressure membrane technology plays a vital role in modern water treatment, with widespread applications in the separation and concentration of industrial wastewater, municipal sewage, rural wastewater, and specialty materials. Pressure membranes are classified by grade into microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO). In terms of membrane materials, organic polymers offer advantages such as low cost, ease of preparation, and simple operation, including polyvinylidene fluoride (PVDF), polyacrylonitrile polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), polyethersulfone (PS), and polysulfone (PES).

[0003] However, membrane fouling is a significant limitation during application, requiring frequent cleaning and maintenance, which increases economic costs. Therefore, developing antifouling and highly hydrophilic membranes is crucial for solving membrane module fouling. Compared to conventional pure water backwashing and chemical cleaning, catalytic oxidation cleaning combines advanced oxidation and membrane separation technologies, representing a novel approach to achieving membrane antifouling. It also offers significant advantages in treating organic pollutants, breaking down stubborn organic matter in the membrane atmosphere. MXene is a novel two-dimensional material with high electrical and thermal conductivity, high surface area, excellent hydrophilicity, and stability. Its ultrathin structure and numerous active terminals allow for tight anchoring of more nanoparticles. Furthermore, the abundant active sites and coordinating unsaturated chemical bonds on the MXene surface provide redox advantages, leading to its application in catalytic oxidation and membrane separation technologies in recent years.

[0004] Therefore, it is necessary to develop and prepare a catalytic membrane that can simultaneously catalytically oxidize organic pollutants through filtration, achieving a synergistic effect. Under advanced oxidation systems, pollutants are degraded and removed, enhancing the membrane's antifouling properties. Among various high-molecular-weight organic polymers, polyvinylidene fluoride (PVDF) not only possesses good mechanical stability, high chemical stability, and high mechanical strength, but also exhibits resistance to acids, alkalis, and ultraviolet radiation, making it suitable for preparing catalytic membranes. Cuprous oxide, as a typical p-type semiconductor, has a high reduction potential, exhibits ideal catalytic effects, and is also a bactericide. Summary of the Invention

[0005] To achieve the above objectives, this invention provides a Cu2O / MXene-PVDF self-cleaning hybrid membrane, its preparation method, and its application, so as to achieve the purpose of anti-fouling and self-cleaning.

[0006] The specific technical solution of the present invention is as follows:

[0007] The first objective of this invention is to provide a method for preparing a Cu2O / MXene-PVDF self-cleaning hybrid membrane, which includes the following steps:

[0008] S1. After adding copper salt and reducing agent to the MXene material solution, ultrasonic dispersion is performed to obtain a mixed liquid, which is then heated to react and obtain Cu2O / MXene composite material.

[0009] S2. The Cu2O / MXene composite material, polymer and surfactant are mixed evenly and reacted to obtain the Cu2O / MXene-PVDF self-cleaning hybrid membrane.

[0010] In a further embodiment, the heating reaction described in step S1 is carried out under conditions of water bath and stirring, with a reaction temperature of 85-95℃ and a time of 5-10 hours.

[0011] The mixture contains 0.1-3 wt% MXene, 3-10 wt% copper salt, and 2-8 wt% reducing agent.

[0012] In a further embodiment, the MXene material solution in step S1 is prepared by adding MXene to deionized water and ultrasonically dispersing it for 30-60 minutes.

[0013] The copper salt is copper chloride, copper acetate, or copper nitrate, and the reducing agent is at least one of urea, glucose, and hydrazine hydrate.

[0014] In a further embodiment, the polymer in step S2 is at least one of PVDF, PVP, and PEG, and the surfactant is Tween 80.

[0015] The Cu2O / MXene-PVDF self-cleaning hybrid membrane is in the shape of a hollow fiber or a flat plate. The hollow fiber shape can be prepared using a spinneret or a spinneret plate, while the flat plate shape can be prepared using a doctor blade.

[0016] In a further embodiment, the reaction described in step S2 refers to either a wet phase inversion method or a hot melt extrusion method. Specifically:

[0017] When the reaction refers to the wet phase inversion method, the Cu2O / MXene composite material is added to an organic solvent and ultrasonically dispersed to obtain a Cu2O / MXene composite material solution. Then, a polymer and a surfactant are added to the Cu2O / MXene composite material solution, and after stirring and mixing, a Cu2O / MXene-PVDF self-cleaning hybrid membrane is obtained by vacuum treatment.

[0018] The polymers therein are composed of PVDF, PVP and PEG in a mass ratio of 15-18:1-3:2-6, and the surfactant is Tween 80, which accounts for 1-3% of the total mass of the mixture.

[0019] The Cu2O / MXene composite solution has a mass fraction of 0.1%-2wt%, preferably 0.1-1wt%; the organic solution is DMAC or DMF.

[0020] The vacuuming process involves evacuating at a temperature of 75-85℃ and a pressure of 0.05-0.1 MPa for 12-15 hours.

[0021] When the reaction refers to the hot melt extrusion method, the mixture of Cu2O / MXene composite material, polymer and surfactant is heated and melted, and then extruded through a twin-screw extruder to obtain Cu2O / MXene-PVDF self-cleaning hybrid membrane.

[0022] In a further embodiment, the thickness of the MXene material is 20-50 μm;

[0023] The MXene material is obtained by etching the MAX phase with an etching solvent. The etching time is 24-48 hours, the temperature is 60-80℃, preferably 65-70℃, and the stirring rate is 200-500 revolutions per minute.

[0024] Preferably, MAX is one of Ti3AlC2, V3AlC2, and Mo3AlC2, and the etching solvent is one of hydrochloric acid and sodium fluoride solution, phosphoric acid and potassium fluoride solution, and ammonium fluoride aqueous solution.

[0025] The second objective of this invention is to provide a Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared by the above-described preparation method.

[0026] The third objective of this invention is to provide an application of the aforementioned Cu2O / MXene-PVDF self-cleaning hybrid membrane in an external column filtration system or an immersion filtration system for the removal of contaminants.

[0027] In a further embodiment, the contaminants include tetrabromobisphenol A, tetracycline, or rhodamine B;

[0028] The Cu2O / MXene-PVDF self-cleaning hybrid membrane operates with a flux of 100-300 LMH in external filtration systems and 15-30 LMH in submerged filtration systems.

[0029] The removal rate of pollutants reaches 91-95%.

[0030] This invention involves the directional anchoring of cuprous oxide nanoparticles onto the surface-active terminals (-F, -OH, -O) of MXene material via a reaction. A Cu₂O / MXene-PVDF hybrid membrane is then prepared through phase inversion or hot-melt extrusion. The catalyst structure is encapsulated by a high-molecular-weight organic compound, thereby mitigating MXene oxidation. Under persulfate oxidation conditions, cuprous oxide activates persulfate, generating reactive oxygen species such as sulfate radicals, hydroxyl radicals, and superoxide radicals, achieving the degradation and removal of organic pollutants. Simultaneously, it alleviates irreversible membrane fouling and enhances the hydrophilicity of the membrane surface, thus achieving self-cleaning properties.

[0031] The beneficial effects of the invention include:

[0032] (1) This invention generates Cu2O / MXene composite material in situ, utilizing the MXene sheet-like confinement structure to enhance electron transport capability, improve catalytic efficiency, and also prevent Cu + A disproportionation reaction occurs.

[0033] (2) The present invention enhances the chemical stability of the catalytic material by organic-inorganic hybridization and a large number of hydrogen bonds at the interface.

[0034] (3) Under the persulfate system, the removal rate of pollutants is improved, the proportion of irreversible fouling on the membrane surface is reduced, and the antifouling performance of the membrane is enhanced.

[0035] (4) This invention constructs stable cuprous oxide nanoparticles on the surface of MXene sheets to enhance the redox properties of the material. Then, through hybridization of organic polymers and inorganic catalysts, multiple functional groups on the surfaces of both are combined, thereby achieving the effect of stabilizing the catalyst and suppressing the defect of MXene being easily oxidized. Through the synergistic effect of advanced oxidation and membrane separation, the irreversible fouling ratio of the membrane is reduced, the flux recovery capability is improved, and the self-cleaning effect of the membrane is achieved. Attached Figure Description

[0036] Figure 1 The images show the SEM and XRD patterns of the Cu2O / MXene composite material prepared in Example 1.

[0037] Figure 2 The images show the surface and cross-sectional SEM images of the Cu2O / MXene self-cleaning hybrid film prepared in Example 1.

[0038] Figure 3 This is a mapping elemental distribution diagram of the Cu2O / MXene self-cleaning hybrid film prepared in Example 1.

[0039] Figure 4 The image shows the EDS elemental content distribution of the Cu2O / MXene self-cleaning hybrid membrane prepared in Example 1. Detailed Implementation

[0040] The present invention will be further described below with reference to specific embodiments, but the essence of the present invention is not limited to the embodiments described below. Unless otherwise specified, the methods described are conventional methods, and the materials described are available from publicly available commercial sources unless otherwise specified. Those skilled in the art should know that any simple modifications or substitutions based on the essence of the present invention fall within the scope of protection claimed by the present invention.

[0041] The performance tests in the following embodiments are as follows:

[0042] The determination method for flat sheet membranes is as follows:

[0043] The pure water flux of the membrane was measured using a dead-end filtration device. The membrane was coated on PET (polyethylene terephthalate) nonwoven fabric with a density of 80 g / m³. 2 The filter membrane was cut to a size of 15.8cm. 2 The pure water flux was measured at an inlet pressure of 1 bar. Jw1=V / (A*t), where V: liquid volume passing through, A: membrane area, and t: filtration time.

[0044] To determine the membrane flux recovery rate, the feed water concentration and humic acid concentration were both 30 mg / L. The membrane was coated on PET (polyethylene terephthalate) nonwoven fabric with a density of 80 g / m², and the filter membrane was cut to a size of 15.8 cm². The concentration of the filtered water was measured under an inlet pressure of 1 bar. After one cycle of operation, the membrane was removed, immersed in ultrapure water, rinsed for 60 minutes, and then irradiated under a 300 W UV lamp for 30 minutes. The pure water flux Jw2 was then measured. The flux recovery rate (FRR) (%) was calculated as: FRR (%) = Jw2 / Jw1

[0045] The determination method for hollow membranes is as follows:

[0046] The pure water flux of the membrane was measured using a cross-flow filtration device. The membrane was cast into a columnar module with an internal surface area of ​​0.15 m². 2 The pure water flux was measured at an inlet pressure of 2 bar. Jw1=V / (A*t), where V: liquid volume passing through, A: membrane area, and t: filtration time.

[0047] Flux recovery rate (FRR) and irreversible fouling index (DRir) determination: The influent concentration was set at 20 mg / L for both pollutants and humic acid. After one operating cycle, the membrane was removed, immersed in ultrapure water for 60 min, rinsed, and then irradiated under a 300W UV lamp for 30 min. The pure water flux Jw2 was then measured. Flux recovery rate (FRR) (%) = Jw2 / Jw1 × 100. Irreversible fouling index (DRir) (%) = ((Jw1-Jw2) / Jw1) × 100

[0048] For pollutant retention rate determination, the influent pollutant concentration and persulfate concentration were set to 20 mg / L under an influent membrane pressure of 2 bar. The concentration and retention rate after retention were measured, R(%) = ((Cf-Cp) / Cf)×100, where Cf is the influent pollutant concentration and Cp is the effluent pollutant concentration.

[0049] Example 1:

[0050] Weigh out 2g of Ti3AlC2 and place it in 80mL of 50% ammonium fluoride solution. Disperse the mixture ultrasonically for 30min and react at 65℃ for 36h at a rate of 500r / min. Wash with anhydrous ethanol until impurities are removed to obtain MXene material with multiple layered structures of Ti3C2Tx, with a thickness of 20-50μm.

[0051] Add 0.5g of the MXene material prepared above to 100mL of deionized water and disperse it by ultrasonication; then weigh 4.5g of copper nitrate trihydrate and 5g of urea and dissolve them in the above dispersion, then transfer them to a beaker and stir in a 90℃ water bath for 6h to obtain Cu2O / MXene catalyst. After the reaction is complete, clean it and vacuum dry it for later use.

[0052] like Figure 1 The SEM and XRD patterns of the Cu2O / MXene composite material prepared in this embodiment are shown. As can be seen from the figure, 110, 111, 200 and 220 are characteristic peaks of cuprous oxide in XRD. And as can be seen from SEM, cuprous oxide particles are uniformly grown on the surface of the MXene layer-transfer structure, indicating that the Cu2O / MXene composite material was successfully synthesized in this embodiment.

[0053] 0.5 g of the prepared Cu₂O / MXene catalyst was dissolved in 55 mL of DMAC (dimethylacetamide) solution and sonicated until completely dispersed. 21 g of PVDF (polyvinylidene fluoride), 10 g of PVP (polyvinylpyrrolidone), 10 mL of PEG400 (polyethylene glycol), and 3 g of Tween 80 were added to the catalyst-DMAC system and stirred thoroughly to dissolve. The mixture was then vacuumed at 85 °C and 0.05 MPa for 15 h. A hollow fibrous Cu₂O / MXene-PVDF self-cleaning hybrid membrane with an inner diameter of 0.7 mm and an outer diameter of 1.3 mm was obtained, with pore sizes ranging from 0.1 to 0.2 μm.

[0054] like Figure 2 The image shows the surface and cross-sectional SEM images of the Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared in this embodiment. As can be seen from the images, the membrane surface has relatively uniform and dense pores. Under the catalytic action of the Cu2O / MXene composite material, the phase transformation of PVDF is hindered, and the cross-sectional pore size is relatively large.

[0055] In the Cu2O / MXene-PVDF self-cleaning hybrid film prepared in this embodiment, copper atoms are uniformly distributed in the film, with a mass percentage of approximately 0.2%.

[0056] Specifically, such as Figure 3 The image shows the elemental distribution of the Cu2O / MXene-PVDF self-cleaning hybrid film prepared in this embodiment, revealing a uniform distribution of copper within the film. Figure 4 The EDS elemental distribution spectrum shows that the mass percentage of copper atoms is 0.2%.

[0057] The Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared in this embodiment was applied to an immersion filtration system for the treatment of tetracycline contaminants. With an initial tetracycline concentration of 20 mg / L and an initial potassium persulfate concentration of 30 mg / L, and an operating flux of 20 LMH, the tetracycline concentration in the effluent was 1.5 mg / L, achieving a tetracycline removal rate of 92.5%. Compared to a simple PVDF microfiltration membrane, the flux recovery rate increased from 75% to 85%, and the irreversible fouling of the membrane decreased from 5% to 1.5%. Through the combined effects of membrane filtration and advanced oxidation, the Cu2O / MXene-PVDF self-cleaning hybrid membrane exhibits high removal efficiency for organic contaminants while simultaneously improving the membrane's antifouling performance.

[0058] Example 2:

[0059] Weigh out 2g of Ti3AlC2 and place it in 80mL of a mixed solution of sodium fluoride and hydrochloric acid. Disperse the mixture ultrasonically for 30min and react at 68℃ for 48h at a rate of 350r / min. Wash with anhydrous ethanol until impurities are removed to obtain MXene material with an accordion-like layered structure of Ti3C2Tx and a thickness of 20-50μm.

[0060] Add 1g of the prepared MXene material to 100mL of deionized water and disperse it by ultrasonication; then weigh 5g of copper chloride and 3g of hydrazine hydrate and dissolve them in the dispersion. Transfer the mixture to a beaker and stir in a 92℃ water bath for 8h to obtain Cu2O / MXene catalyst. After the reaction is complete, clean the catalyst and vacuum dry it for later use.

[0061] 1 g of the prepared Cu2O / MXene catalyst was weighed and added to 60 mL of DMF (dimethylformamide) solution, and sonicated until completely dispersed. 24 g of PVDF (polyvinylidene fluoride), 5 g of PVP (polyvinylpyrrolidone), 8 mL of PEG400 (polyethylene glycol), and 2 g of Tween 80 were weighed and added to the aforementioned catalyst-DMAC system, stirred thoroughly to dissolve, and vacuumed at 80 °C and 0.05 MPa for 12 h. A flat Cu2O / MXene-PVDF self-cleaning hybrid membrane with a thickness of 200 mm and a pore size of 0.1–0.4 μm was prepared using a doctor blade.

[0062] The Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared in this embodiment was applied to a cup filtration system for the treatment of tetrabromobisphenol A (TBA) contaminants. With an initial TBA concentration of 30 mg / L and an initial potassium persulfate concentration of 50 mg / L, and an operating flux of 10 LMH, the TBA concentration in the effluent was 2.5 mg / L, achieving a TBA removal rate of 91.6%. Compared to a simple PVDF microfiltration membrane, the flux recovery rate increased from 81.5% to 89.5%, and the irreversible fouling of the membrane was as low as 2%. Through the combined effects of membrane filtration and advanced oxidation, the Cu2O / MXene-PVDF self-cleaning hybrid membrane exhibits high removal efficiency for organic pollutants and enhances the membrane's antifouling performance.

[0063] Example 3:

[0064] Weigh out 2g of Ti3AlC2 and place it in 80mL of phosphoric acid and potassium fluoride solution. Disperse ultrasonically for 30min and react at 70℃ for 48h at a rate of 400r / min. Wash with anhydrous ethanol until impurities are removed. The prepared Ti3C2Tx MXene material consists of multiple stacked layered structures with a thickness of 20–50μm.

[0065] 1.5 g of the MXene material prepared above was added to 100 mL of deionized water and ultrasonically dispersed. Then, 5.5 g of copper acetate dihydrate and 6 g of glucose were weighed and dissolved in the dispersion. The solution was transferred to a beaker and stirred in a 92°C water bath for 6 h to obtain the Cu2O / MXene catalyst. After the reaction was complete, the catalyst was cleaned and vacuum dried for later use.

[0066] 0.2 g of the Cu2O / MXene catalyst, 5.8 g of Tween 80, and 85 g of PVDF6010 (polyvinylidene fluoride) prepared above were weighed and mixed in a mixer and heated. The mixture was melted at 220°C under multi-stage heating and extruded through a twin-screw extruder to prepare a hollow membrane. A hollow fibrous Cu2O / MXene-PVDF self-cleaning hybrid membrane with an inner diameter of 0.8 mm and an outer diameter of 1.5 mm was obtained, with a pore size of 0.03–0.05 μm.

[0067] The Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared in this embodiment was applied to a column filtration system for the treatment of Rhodamine B contaminant. With an initial concentration of 30 mg / L for both Rhodamine B and potassium persulfate, and an operating flux of 100 LMH, the concentration of Rhodamine B in the effluent was 1.5 mg / L, achieving a removal rate of 95%. Compared to a simple PVDF ultrafiltration membrane, the flux recovery rate increased from 80% to 83%, and irreversible membrane fouling decreased to 3%. Through the combined effects of membrane filtration and advanced oxidation, the Cu2O / MXene-PVDF self-cleaning hybrid membrane exhibits high removal efficiency for Rhodamine B while simultaneously improving the membrane's antifouling performance, achieving catalytic self-cleaning.

[0068] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications can be made to the embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a Cu2O / MXene-PVDF self-cleaning hybrid membrane, characterized in that: Includes the following steps: S1. After adding copper salt and reducing agent to the MXene material solution, ultrasonic dispersion is performed to obtain a mixed liquid, which is then heated to react and obtain Cu2O / MXene composite material. S2. Mix Cu2O / MXene composite material, polymer and surfactant evenly, and react to obtain Cu2O / MXene-PVDF self-cleaning hybrid membrane.

2. The preparation method according to claim 1, characterized in that: The heating reaction described in step S1 is carried out under the conditions of water bath and stirring, with a reaction temperature of 85-95℃ and a time of 5-10h.

3. The preparation method according to claim 1, characterized in that: The mixture contains 0.1-3 wt% MXene, 3-10 wt% copper salt, and 2-8 wt% reducing agent.

4. The preparation method according to claim 1, characterized in that: The MXene material solution mentioned in step S1 is obtained by adding MXene to deionized water and ultrasonically dispersing it for 30-60 minutes. The copper salt is copper chloride, copper acetate, or copper nitrate, and the reducing agent is at least one of urea, glucose, and hydrazine hydrate.

5. The preparation method according to claim 1, characterized in that: The polymer mentioned in step S2 is composed of PVDF, PVP and PEG, and the surfactant is Tween 80; The Cu2O / MXene-PVDF self-cleaning hybrid membrane is in the shape of a hollow fiber or a flat plate.

6. The preparation method according to claim 1, characterized in that: The reaction described in step S2 refers to the wet phase inversion method, which involves first adding the Cu2O / MXene composite material to an organic solvent and ultrasonically dispersing it to obtain a Cu2O / MXene composite material solution. Then, a polymer and a surfactant are added to the Cu2O / MXene composite material solution, and finally the mixture is stirred and mixed to obtain a mixture. The mixture is then vacuum-treated to obtain a Cu2O / MXene-PVDF self-cleaning hybrid membrane. The polymers are composed of PVDF, PVP and PEG in a mass ratio of 15-18:1-3:2-6, and the surfactant is Tween 80, which accounts for 1-3% of the total mass of the mixture.

7. The preparation method according to claim 6, characterized in that: The Cu2O / MXene composite solution has a mass fraction of 0.1%-2wt%; the organic solution is DMAC or DMF. The vacuuming process involves evacuating at a temperature of 75-85℃ and a pressure of 0.05-0.1 MPa for 12-15 hours.

8. The preparation method according to claim 7, characterized in that: The mass fraction of the Cu2O / MXene composite solution is 0.1%-1wt%.

9. The preparation method according to claim 1, characterized in that: The reaction described in step S2 refers to the hot melt extrusion method, in which a mixture of Cu2O / MXene composite material, polymer and surfactant is heated and melted, and then extruded through a twin-screw extruder to obtain a Cu2O / MXene-PVDF self-cleaning hybrid membrane.

10. The preparation method according to claim 1, characterized in that: The thickness of the MXene material is 20-50 μm; The MXene material is obtained by etching the MAX phase with an etching solvent, wherein the etching time is 24-48 hours, the temperature is 60-80℃, and the stirring rate is 200-500 revolutions per minute. The MAX is one of Ti3AlC2, V3AlC2, and Mo3AlC2, and the etching solvent is one of hydrochloric acid and sodium fluoride solution, phosphoric acid and potassium fluoride solution, and ammonium fluoride aqueous solution.

11. The preparation method according to claim 10, characterized in that: The etching temperature is 65-70℃.

12. A Cu2O / MXene-PVDF self-cleaning hybrid membrane prepared by the preparation method according to any one of claims 1-11.

13. An application of the Cu2O / MXene-PVDF self-cleaning hybrid membrane as described in claim 12, characterized in that: It is used in external column filtration systems or submersible filtration systems to remove contaminants.

14. The application according to claim 13, characterized in that: The contaminants include tetrabromobisphenol A, tetracycline, or rhodamine B; The Cu2O / MXene-PVDF self-cleaning hybrid membrane operates with a flux of 100-300 LMH in external filtration systems and 15-30 LMH in submerged filtration systems. The removal rate of pollutants reaches 91-95%.

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