A photocatalytic device and method for treating chlorophenol organic wastewater

Abstract

This invention discloses a photocatalytic treatment device and method for chlorophenol organic wastewater, comprising a first pipe and a second pipe, the second pipe being connected to the interior of the first pipe via the side of the first pipe; a first quick-connect connector and a second quick-connect connector with sealing at both ends of the first pipe respectively, the first quick-connect connector holding a light-transmitting element for quick replacement; the second quick-connect connector holding a photocatalytic-capacitor deionization coupling element with its photocatalytic layer facing the light-transmitting element, and the cathode and anode of the second quick-connect connector extending outward for connection to a power source.

Description

Technical Field

[0001] This invention relates to the field of advanced wastewater treatment and resource recovery technology, specifically to a photocatalytic treatment device and method for chlorophenol organic wastewater. It is particularly suitable for the deep mineralization treatment of highly toxic and recalcitrant organic pollutants such as chlorophenols, and can be widely applied in the fields of achieving standard discharge and resource recovery of chlorophenol organic wastewater in industries such as chemical, pesticide, and printing and dyeing. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] Chlorophenols (such as 2,4-dichlorophenol (2,4-DCP)) are typical persistent organic pollutants emitted during the production processes of chemical, pesticide, and pharmaceutical industries. Their detected concentrations are typically in the range of 0.1–100 mg / L, and they are highly toxic (LD50). 50 Pollutants with a concentration of <500 mg / kg, poor biodegradability (BOD5 / COD<0.2), and environmental accumulation can accumulate through the food chain, posing a serious threat to aquatic ecosystems and human health. They have been included in the list of priority pollutants controlled in the "Surface Water Environmental Quality Standard" (GB 3838-2002).

[0004] Traditional water treatment methods, such as physical adsorption and conventional biological treatment, have significant limitations, often resulting in low removal efficiency, secondary pollution, and incomplete mineralization. Photocatalysis technology utilizes light energy to generate highly reactive oxidizing species, achieving efficient degradation and even mineralization of organic pollutants. However, high-salinity wastewater contains high concentrations of salt ions (such as Cl-). - Na + Ca 2 + Salt ions inhibit photocatalyst activity through the following pathways: First, the competitive adsorption of salt ions on the catalyst surface occupies active sites, reducing the probability of contact between pollutants and active species; second, salt ions capture photogenerated carriers, accelerating electron-hole recombination, thus decreasing the photocatalytic quantum yield and ultimately reducing wastewater treatment efficiency by 30%–60%. Capacitive deionization (CDI) technology, by applying a low-voltage electric field to the electrodes, drives salt ions to migrate to the electrode surface and be adsorbed by the electrochemical double layer, effectively reducing the salt ion concentration in wastewater and mitigating the inhibitory effect of salt ions on photocatalytic performance. In recent years, photocatalysis and CDI have been coupled to form a photocatalysis-capacitive deionization coupling system (PC_CDI). The electric field promotes the separation of photogenerated carriers, improving photocatalytic efficiency; simultaneously, the photocatalytic process can alter the morphology of pollutants, enhancing their adsorption or electrochemical conversion on the electrode surface. Furthermore, for the removal of chlorophenol wastewater, Cl- can be removed, inhibiting the formation of highly toxic chlorine-containing products.

[0005] However, existing laboratory-scale photocatalytic or electrochemical reactors mostly employ beaker, column, or plate-and-frame structures, which suffer from the following technical defects, limiting the industrial application and mechanism research of PC-CDI coupling technology: ① The device consists of multiple independent components connected by bolts, flanges, or adhesives, resulting in cumbersome assembly, long assembly time (30-60 minutes per assembly), poor sealing performance at the joints, risk of wastewater leakage, and inconvenience for frequent disassembly and assembly to replace or study different types of electrodes / photocatalytic materials; ② The design of the photo-electric synergistic interface is unreasonable. For P-CDI reactions requiring illumination, the illumination window is usually fixed or difficult to align, resulting in light energy utilization of less than 50%, and uneven distribution of light intensity on the catalyst layer surface, affecting reaction stability; ③ The electrode spacing cannot be precisely controlled (the error is usually greater than 0.5 mm), leading to uneven electric field distribution and electric field intensity fluctuations exceeding 20%, significantly affecting the efficiency of capacitive deionization and desalination and the separation effect of photogenerated carriers; ④ The reactor flow field design is unreasonable, and the contact time between wastewater and the catalyst layer / electrode is short and insufficient, resulting in low pollutant degradation rate and salt ion removal rate, which is difficult to meet the actual wastewater treatment needs. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a photocatalytic treatment device and method for chlorophenol organic wastewater, which solves the technical problems of existing reactors such as cumbersome assembly, low light utilization, uneven electric field distribution, and poor synergistic effect. At the same time, it can be extended to the efficient and stable treatment of chlorophenol organic wastewater, and provides technical support for the promotion of PC-CDI coupling technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides a photocatalytic treatment device for chlorophenol organic wastewater, comprising a first pipe and a second pipe, wherein the second pipe is connected to the interior of the first pipe through the side of the first pipe; The first pipe is equipped with a first quick-connect fitting and a second quick-connect fitting with sealing at both ends. The first quick-connect fitting holds a light-transmitting element for quick replacement of the light-transmitting element. The second quick connector has an inner sealing clamp holding a photocatalytic-capacitor deionization coupling element, with its photocatalytic layer facing the light-transmitting element. The cathode and anode of the second quick connector extend outward for connection to a power source.

[0008] Secondly, the present invention provides a photocatalytic treatment method for chlorophenol-based organic wastewater, comprising the following steps: The photocatalytic treatment device for the chlorophenol organic wastewater is assembled. The photocatalytic-capacitor deionization coupling element includes a Cu mesh / Cu2Se / CN photocatalytic membrane, a non-woven fabric isolation layer, a CNT carbon fiber membrane and a steel mesh stacked in sequence. The photocatalytic surface of the Cu mesh / Cu2Se / CN photocatalytic membrane faces the light-transmitting element. The light source is directed towards the Cu mesh / Cu2Se / CN photocatalytic membrane through the light-transmitting element; Connect the Cu mesh / Cu2Se / CN photocatalytic membrane and the steel mesh to a power source, making the Cu mesh / Cu2Se / CN photocatalytic membrane the cathode and the steel mesh and CNT carbon fiber membrane the anode; The organic wastewater to be treated is introduced into the first pipe through the second pipe. The organic wastewater undergoes photocatalytic-capacitor deionization treatment as it flows out of the photocatalytic-capacitor deionization element. The treated organic wastewater flows out from the outlet.

[0009] The beneficial effects achieved by one or more embodiments of the present invention described above are as follows: The first pipe forms the main channel for wastewater flow, and the second pipe is connected to the first pipe on the side to form a T-shaped structure, which is used to introduce the wastewater to be treated and ensure that the wastewater flows evenly through the photocatalytic-capacitor deionization coupling element to provide a stable flow field environment for the reaction.

[0010] The first quick-connector seals and clamps the light-transmitting element (such as a quartz glass window), enabling efficient light transmission and supporting rapid replacement of the light-transmitting element. The light-transmitting element is positioned directly opposite the photocatalytic film, effectively solving the problem of light energy loss caused by difficulty in light alignment and significantly improving light utilization efficiency.

[0011] The second quick connector is used to seal and clamp the sequentially stacked photocatalytic layers (such as Cu mesh / Cu2Se / CN photocatalytic membrane), non-woven isolation layer, CNT carbon fiber membrane and steel mesh, forming the core reaction unit of cathode-isolation layer-anode.

[0012] The quartz glass window provides an optimal light transmission path, ensuring that the high-intensity light source reaches the surface of the cathode catalytic film directly. The precisely controlled 1 mm electrode spacing facilitates the formation of a uniform and strong electric field, promoting the separation of photogenerated electrons and holes. This structure provides an ideal and standardized verification platform for the synergistic mechanism of photocatalysis and capacitive deionization.

[0013] This modular pipe fitting can be connected in series or parallel as a core unit to expand processing capacity. Furthermore, the device can be fabricated using 3D printing, significantly reducing the manufacturing cost and barriers to entry for complex structural components, thus facilitating the widespread adoption of this technology. Attached Figure Description

[0014] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0015] Figure 1 This is a physical diagram of the device of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention; Figure 3 This is a cross-sectional structural diagram of the present invention; Figure 4 This is a schematic diagram of the main structure of the present invention; Figure 5 This is a schematic diagram of the left-side structure of the present invention; Figure 6 This is a graph showing the degradation of 2,4-DCP by a quick-connect tee fitting based on photocatalytic-capacitive deionization coupling technology in an embodiment of the present invention.

[0016] In the diagram: 1. First snap-fit ​​quick connector; 2. First annular groove; 3. O-ring seal; 4. Quartz glass window; 5. First quartz glass slot; 6. Second quartz glass slot; 7. Second snap-fit ​​quick connector; 8. Second annular groove; 9. First pipe; 10. Liquid inlet pipe slot; 11. Liquid inlet; 12. Third snap-fit ​​quick connector; 13. Third annular groove; 14. Fourth snap-fit ​​quick connector; 15. Fourth annular groove; 16. Cu mesh / Cu2Se / CN photocatalytic membrane; 17. Non-woven fabric isolation layer; 18. CNT carbon fiber membrane; 19. Steel mesh; 20. Electrode insertion hole; 21. Electrode slot; 22. Electrode clamping tube; 23. Drain pipe slot; 24. Drain outlet. Detailed Implementation

[0017] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0018] In view of the technical problems mentioned in the background art, the present invention provides a photocatalytic treatment device for chlorophenol organic wastewater, including a first pipe and a second pipe, wherein the second pipe is connected to the interior of the first pipe through the side of the first pipe; The first pipe is equipped with a first quick-connect fitting and a second quick-connect fitting with sealing at both ends. The first quick-connect fitting holds a light-transmitting element for quick replacement of the light-transmitting element. The second quick connector has an inner sealing clamp holding a photocatalytic-capacitor deionization coupling element, with its photocatalytic layer facing the light-transmitting element. The cathode and anode of the second quick connector extend outward for connection to a power source.

[0019] The first pipe forms the main channel for wastewater flow, and the second pipe is connected to the first pipe on the side to form a T-shaped structure, which is used to introduce the wastewater to be treated and ensure that the wastewater flows evenly through the photocatalytic-capacitor deionization coupling element to provide a stable flow field environment for the reaction.

[0020] The first quick-connector seals and clamps the light-transmitting element (such as a quartz glass window), enabling efficient light transmission and supporting rapid replacement of the light-transmitting element. The light-transmitting element is positioned directly opposite the photocatalytic film, effectively solving the problem of light energy loss caused by difficulty in light alignment and significantly improving light utilization efficiency.

[0021] The second quick connector is used to seal and clamp the sequentially stacked photocatalytic layers (such as Cu mesh / Cu2Se / CN photocatalytic membrane), non-woven isolation layer, CNT carbon fiber membrane and steel mesh, forming the core reaction unit of cathode-isolation layer-anode.

[0022] The cathode (Cu mesh / Cu2Se / CN photocatalytic membrane) combines photocatalytic activity and conductivity, generating strong oxidizing species to degrade organic matter under illumination, while simultaneously adsorbing cations; the anode (steel mesh + CNT carbon fiber membrane) provides high specific surface area electro-adsorption sites to adsorb anions. A low-voltage electric field is applied through the leads of the cathode and anode to drive ion directional migration, promote the separation of photogenerated electrons and holes, and reduce the inhibitory effect of salt ions on the photocatalyst through capacitive deionization.

[0023] The non-woven fabric isolation layer is used to precisely control the electrode spacing, ensure the uniformity of the electric field, and also serves as a wastewater flow channel.

[0024] In some embodiments, the angle between the first pipe and the second pipe is 30-90°, and preferably, the first pipe and the second pipe are arranged perpendicularly.

[0025] The vertical layout allows wastewater to enter the first pipe vertically from the side, forming radial flow, that is, from the pipe wall to the center or from the center to the surroundings, rather than a parallel unidirectional direct flow. This avoids the problem of uneven local flow velocity that may occur when parallel settings are used, and ensures that wastewater flows evenly through the reaction interface of the photocatalytic-capacitor deionization coupling element, thereby improving the contact efficiency between pollutants and catalysts and electrodes. The vertical structure makes the axis of the second pipe perpendicular to that of the first pipe, avoiding interference between the liquid inlet direction and the light illumination direction (along the axis of the first pipe), ensuring that the light source can directly shine on the surface of the photocatalytic layer after passing through the light-transmitting element, and reducing light refraction or shading loss caused by the tilt of the flow channel. The T-shaped vertical structure can be integrated through 3D printing, reducing connecting parts and lowering the risk of leakage. At the same time, the standardized vertical interface facilitates the expansion of multiple devices in series or parallel, flexibly adapting to different processing scale requirements.

[0026] Preferably, the end of the second pipe is provided with an inlet pipe groove for connecting the inlet pipe.

[0027] In some embodiments, the first quick connector includes a first snap-fit ​​quick connector and a second snap-fit ​​quick connector that are configured to cooperate with each other. Each snap-fit ​​quick connector has at least two claws and two flanges symmetrically arranged in the circumferential direction. The claws and flanges are rotated and engaged to quickly connect or disconnect the two snap-fit ​​quick connectors.

[0028] Preferably, the claws and flanges of the same quick-connect coupling are alternately arranged, and one side of the flange is connected to the claw, while the other side is spaced apart from another claw by a distance greater than the width of the claw.

[0029] The claws and flanges are alternately distributed circumferentially, allowing the claws and flanges of two mating joints to engage with each other. When the joint rotates, the claws of one joint can engage with the flange gap of the other joint, forming a mechanical lock and enabling rapid connection. The distance between the flange and the adjacent claw is greater than the width of the claw, providing sufficient entry space for the claws of the mating joint and avoiding difficulties in engagement or structural damage due to dimensional interference.

[0030] The alternating arrangement ensures that the claws and flanges are evenly distributed circumferentially. After rotation and engagement, they can generate a uniform compression force on the sealing ring, ensuring a tight fit and achieving a leak-free seal under low-pressure conditions.

[0031] Preferably, the inner side of the first quick connector is provided with a first annular groove, and a sealing ring is provided inside the groove.

[0032] The system uses snap-fit ​​connectors and O-ring seals, allowing for tool-free assembly and disassembly of the entire pipe set, greatly facilitating electrode replacement, system cleaning, and maintenance.

[0033] 3D printing ensures the flatness of all connection surfaces, and combined with pre-compressed O-rings, leak-free operation can be achieved under working pressures below 0.1 MPa. All quick-connect fittings have pre-set standardized sealing ring grooves and use universal O-rings. The clamping and locking mechanism generates uniform clamping force, ensuring long-term reliable sealing under low-pressure gravity flow conditions and eliminating leakage.

[0034] Preferably, the first and second quick-connect couplings have annular grooves on their opposite surfaces for clamping and fixing the light-transmitting element.

[0035] Preferably, the structure of the second quick connector is the same as that of the first quick connector.

[0036] In a further preferred embodiment, the inner side of the second quick connector is provided with a second annular groove, and a sealing ring is provided inside the groove.

[0037] More preferably, the photocatalytic-capacitor deionization coupling element includes a Cu mesh / Cu2Se / CN photocatalytic film, a non-woven fabric isolation layer, a CNT carbon fiber film, and a steel mesh stacked sequentially, with the photocatalytic surface of the Cu mesh / Cu2Se / CN photocatalytic film facing the light-transmitting element.

[0038] Preferably, the thickness of the nonwoven fabric isolation layer is 0.5-1.5 mm.

[0039] The anode assembly consists of a steel mesh and a CNT carbon fiber membrane. The CNT carbon fiber membrane, with its high specific surface area and conductivity, provides electroadsorption sites for the anode. The cathode assembly is a Cu mesh / Cu₂Se / CN photocatalytic membrane, possessing both conductivity and photocatalytic activity, capable of adsorbing anions under an electric field. Precise control of the anode-cathode spacing is achieved through a non-woven fabric isolation layer of specific thickness, ensuring electric field uniformity and promoting efficient ion migration.

[0040] A low-voltage electric field is applied between the anode and cathode. Under the influence of the electric field, ions migrate directionally, with cations moving towards the cathode and anions moving towards the anode. An electrical bilayer is formed on the surfaces of the CNT carbon fiber membrane (anode) and the Cu mesh / Cu2Se / CN photocatalytic membrane (cathode), adsorbing ions that have migrated to the electrode surface through electrostatic attraction. The porous structure of the non-woven fabric isolation layer forms channels for the organic wastewater. The wastewater to be treated flows through the electrode surface under gravity, allowing ions to fully contact and be adsorbed by the electrodes.

[0041] In some embodiments, the end of the second quick-connect fitting is connected to a drain pipe groove.

[0042] In some embodiments, the distance between the light-transmitting element and the photocatalytic-capacitive deionization coupling element is 80-100 mm.

[0043] Secondly, the present invention provides a photocatalytic treatment method for chlorophenol-based organic wastewater, comprising the following steps: The photocatalytic treatment device for the chlorophenol organic wastewater is assembled. The photocatalytic-capacitor deionization coupling element includes a Cu mesh / Cu2Se / CN photocatalytic membrane, a non-woven fabric isolation layer, a CNT carbon fiber membrane and a steel mesh stacked in sequence. The photocatalytic surface of the Cu mesh / Cu2Se / CN photocatalytic membrane faces the light-transmitting element. The light source is directed towards the Cu mesh / Cu2Se / CN photocatalytic membrane through the light-transmitting element; Connect the Cu mesh / Cu2Se / CN photocatalytic membrane and the steel mesh to a power source, making the Cu mesh / Cu2Se / CN photocatalytic membrane the cathode and the steel mesh and CNT carbon fiber membrane the anode; The organic wastewater to be treated is introduced into the first pipe through the second pipe. The organic wastewater undergoes photocatalytic-capacitor deionization treatment as it flows out of the photocatalytic-capacitor deionization coupling element. The treated organic wastewater flows out from the outlet.

[0044] When organic wastewater flows through a photocatalytic-capacitor deionization coupling element, the flow rate per unit area is 200-600 L / h / m². 2 .

[0045] In some embodiments, the CNT carbon fiber membrane is composed of aminated carbon nanotubes in polyacrylonitrile (PAN) and / or N,N The dimethylformamide spinning solution is electrospun into a fiber membrane, which is then pre-oxidized in air at 200-250℃ for 2 h, and then carbonized in nitrogen at 750-850℃ for 1-3 h to obtain the final product.

[0046] In some embodiments, the Cu mesh / Cu2Se / CN photocatalytic membrane is prepared by reacting sodium hydroxide, sodium borohydride and selenium powder in water to generate a precursor solution; The clean copper mesh was immersed in the precursor solution and reacted for 1-3 h. After being removed and dried under vacuum, the copper mesh loaded with Cu2Se was obtained (Cu mesh / Cu2Se). Carbon nitride powder, ethyl cellulose, polyvinylidene fluoride, terpineol, anhydrous ethanol and acetic acid are mixed and ground into a uniform slurry. The slurry is then coated onto the surface of the Cu mesh / Cu2Se and dried and cured to obtain the final product.

[0047] The slurry is uniformly loaded onto a Cu mesh / Cu2Se using a screen printing method.

[0048] Preferably, the mass ratio of carbon nitride powder, ethyl cellulose, polyvinylidene fluoride, terpineol, anhydrous ethanol and acetic acid is (0.05-0.2):(0.01-0.1):(0.01-0.1):(0.5-2):(0.3-1.5):(0.02-0.1).

[0049] The present invention will be further described below with reference to the embodiments.

[0050] Example 1 Using a photopolymer 3D printer and rigid photosensitive resin, the first quick-connect coupling 1, the first pipe 9, and the electrode clamping tube 22 were printed according to the designed 3D model (30 mm inner diameter, 1 mm wall thickness). After printing, the parts were cleaned with ethanol, post-cured, and the sealing grooves and connecting surfaces were lightly polished to ensure a smooth surface. A waterproof coating was then applied to the surface, and the parts were allowed to dry.

[0051] A photocatalytic treatment device for chlorophenol-based organic wastewater, such as Figure 1-5As shown, the reactor includes a first snap-fit ​​quick connector 1, a first pipe 9, and an electrode clamping tube 22. The first snap-fit ​​quick connector 1 serves as a light-transmitting top cover, with a high-transmittance quartz glass window 4 embedded in its center. The quartz glass window 4 is positioned between a first quartz glass slot 5 and a second quartz glass slot 6 to introduce an external light source. The lower part of the connector has a first annular groove 2 and an O-ring seal 3 to ensure a tight seal when connected to the lower part. The first pipe 9 serves as the reactor body and liquid inlet unit, with a second snap-fit ​​quick connector 7 and a third snap-fit ​​quick connector 12 at its upper and lower ends, respectively. Each quick connector has a second annular groove 8 and a third annular groove 13, and is equipped with an O-ring seal 3. A liquid inlet 11 is provided on the side wall, and a liquid inlet pipe slot 10 is provided between the liquid inlet 11 and the first pipe 9 for connecting the liquid inlet pipe. The electrode clamping tube 22 serves as the electrode chamber and liquid outlet unit. Its upper end is provided with a fourth quick-connect coupling 14 for connecting to the first pipe 9. The upper part of the coupling is provided with a fourth annular groove 15 and an O-ring seal 3. The inside is provided with a coaxial cylindrical electrode slot 21 for fixing the electrode assembly. The side wall has an electrode insertion hole 20 for wire lead-out. Its bottom is provided with a drain port 24. A drain pipe slot 23 is provided between the drain port 24 and the electrode clamping tube 22 for connecting the drain pipe.

[0052] See Figure 3 and Figure 5 In the above embodiment, a steel mesh 19, a CNT carbon fiber film 18, a non-woven fabric isolation layer 17, and a Cu mesh / Cu2Se / CN photocatalytic film 16 are sequentially placed from bottom to top in the electrode slot 21 of the electrode clamping tube 22. Ensure that each layer is aligned, and that the tails of the strip leads of the steel mesh 19 and the Cu mesh / Cu2Se / CN photocatalytic film 16 are aligned with the positions of the electrode insertion holes 20. Align the fourth quick-connect coupling 14 at the upper end of the assembled electrode clamping tube 22 with the third quick-connect coupling 12 at the lower end of the first pipe 9, press vertically and rotate 90° to complete the sealing connection. Similarly, fasten the first quick-connect coupling 1 with the quartz glass window 4 and O-ring 3 installed with the second quick-connect coupling 7 at the upper end of the main tube, press vertically and rotate 90° to complete the sealing connection. Insert the inlet pipe into the inlet pipe slot 10 and the drain pipe into the drain pipe slot 23. Lead the anode and cathode leads out from the electrode socket 20, connect the steel mesh 19 to the positive terminal of the DC power supply, and connect the Cu mesh / Cu2Se / CN photocatalytic membrane 16 to the negative terminal of the power supply.

[0053] The preparation method of Cu mesh / Cu2Se / CN photocatalytic film 16 is as follows: S1. Place 4 g of sodium hydroxide in 25 mL of deionized water and sonicate until completely dissolved; S2. Add 0.08 g of selenium powder and 0.378 g of sodium borohydride to the solution prepared in step S1, and sonicate until completely dissolved; S3. Immerse a copper mesh with a diameter of 32 mm into the solution prepared in step S2, react for 2 h, remove it, wash it with deionized water and ethanol, and dry it under vacuum at 60 °C to obtain a copper mesh loaded with Cu2Se (Cu mesh / Cu2Se). S4. Mix 0.1 g carbon nitride, 0.05 g ethyl cellulose, 0.05 g polyvinylidene fluoride, 1 mL terpineol, 0.75 mL anhydrous ethanol and 0.1 mL acetic acid, and grind to form a uniform slurry; S5. The slurry prepared in step S4 is screen-printed onto one side of the Cu mesh / Cu2Se, dried at 80°C, and the printing is repeated 3 times to obtain the Cu mesh / Cu2Se / CN photocatalytic film 16.

[0054] The preparation method of NH2-CNT carbon fiber membrane 18 is as follows: S1. Place 0.02 g of aminated carbon nanotubes (NH2-CNT) in 8.5 mL of N,N-dimethylformamide solution and sonicate until completely dissolved; S2. Add 1.5 g of polyacrylonitrile (PAN) to the solution prepared in step S1, and stir magnetically to obtain a uniform spinning solution; S3. 8 mL of the spinning solution prepared in step S2 is loaded into an electrospinning device and spun at a voltage of 15 kV, a feed rate of 1 mL / h, and a receiving distance of 15 cm to obtain a PAN / NH2-CNT composite fiber membrane. S4. The fiber membrane prepared in step S3 is placed in a muffle furnace and pre-oxidized in air at 240°C for 2 hours. S5. The pre-oxidized fiber membrane prepared in step S4 is placed in a tube furnace and carbonized at 800°C for 2 h under a nitrogen atmosphere. After natural cooling, NH2-CNT carbon fiber membrane 18 is obtained.

[0055] The nonwoven fabric isolation layer 17 and the NH2-CNT carbon fiber membrane 18 are both cut into circular pieces with a diameter of 32 mm. The Cu mesh / Cu2Se / CN photocatalytic membrane 16 and the steel mesh 19 are both cut into circular pieces with a diameter of 32 mm and lead tails with a width of 4 mm and a length of 10 mm.

[0056] A 300 W xenon lamp with an AM 1.5 filter was used as a simulated solar light source, positioned vertically directly above quartz glass window 4, with the center of the light spot at a fixed distance of 10 cm from the cathode film surface. A constant DC voltage of 2 V was applied between the anode and cathode. (See also...) Figure 3 The distance between electrodes is precisely controlled by a 1 mm thick nonwoven fabric isolation layer 17.

[0057] Under the above conditions, the photocatalytic treatment device of this embodiment was connected to a continuous flow treatment system for performance testing. A 2,4-DCP solution with an initial concentration of 20 mg / L entered the first pipe 9 from the inlet 11 at a constant flow rate of 200 mL / h, corresponding to a membrane flux of approximately 283 L / m². 2 The 2,4-DCP solution enters the electrode clamping tube 22 under gravity, flows sequentially through the illuminated cathode surface, the isolation layer pores, and the anode surface, undergoes the dual synergistic effect of photocatalysis and capacitive deionization, and finally the degraded solution flows out from the drain port 24.

[0058] To verify the synergistic effect of the photocatalytic-capacitor deionization coupling system of this invention, comparative experiments were set up: a photocatalytic group alone, a capacitor deionization group alone, and a photocatalytic-capacitor deionization coupling group. All three groups used the same reactor body, electrode materials, and influent conditions. The only difference was that the photocatalytic group alone only activated illumination, the capacitor deionization group alone applied voltage, and the photocatalytic-capacitor deionization group activated both illumination and voltage simultaneously.

[0059] During operation, samples are taken periodically to determine the concentration of 2,4-DCP.

[0060] Figure 6 This is a graph showing the degradation results of 2,4-DCP solution by a quick-connect tee fitting based on the electrode material prepared in Example 1. It can be seen that the photocatalytic effect alone is limited, with a degradation efficiency of only about 41% for 2,4-DCP within 10 h, indicating that the photocatalytic group alone has a weak ability to degrade the target pollutant in this system.

[0061] The standalone capacitive deionization system exhibited some adsorption / enrichment effects, with a stable degradation efficiency of approximately 35% for 2,4-DCP within 10 h, mainly attributed to the electroadsorption effect of the electrode. The photocatalysis-capacitive deionization coupling system demonstrated a significant synergistic effect, with a degradation efficiency (approximately 82%) far superior to that of the standalone photocatalysis and capacitive deionization systems.

[0062] This indicates that in the integrated device provided by the present invention, the electric field effectively promotes the separation of photogenerated electrons and holes, improving quantum efficiency; at the same time, the photocatalytic process may change the morphology of pollutants or generate intermediate products, making them easier to be electrochemically removed on the electrode surface, thereby achieving a synergistic degradation effect.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A photocatalytic treatment device for chlorophenol-based organic wastewater, characterized in that: It includes a first pipe and a second pipe, with the second pipe communicating with the interior of the first pipe through the side of the first pipe; The first pipe is equipped with a first quick-connect fitting and a second quick-connect fitting with sealing at both ends. The first quick-connect fitting holds a light-transmitting element for quick replacement of the light-transmitting element. The second quick connector has an inner sealing clamp holding a photocatalytic-capacitor deionization coupling element, with its photocatalytic layer facing the light-transmitting element. The cathode and anode of the second quick connector extend outward for connection to a power source.

2. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 1, characterized in that: The angle between the first pipe and the second pipe is 30-90°, and preferably, the first pipe and the second pipe are set perpendicular to each other.

3. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 1, characterized in that: The first quick connector includes a first snap-fit ​​quick connector and a second snap-fit ​​quick connector that are configured to cooperate with each other. Each snap-fit ​​quick connector has at least two claws and two flanges symmetrically arranged in the circumferential direction. The claws and flanges are rotated and engaged to quickly connect or disconnect the two snap-fit ​​quick connectors.

4. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 3, characterized in that: The claws and flanges of the same quick-connect coupling are arranged alternately, with one side of the flange connected to the claw and the other side spaced apart from the other claw by a distance greater than the width of the claw.

5. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 1, characterized in that: The first quick connector has a first annular groove on its inner side, and a sealing ring is provided inside it.

6. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 3, characterized in that: The first and second quick-connect couplings have annular grooves on their opposite surfaces for clamping and fixing the light-transmitting element.

7. The photocatalytic treatment device for chlorophenolic organic wastewater according to claim 3, characterized in that: The structure of the second quick connector is the same as that of the first quick connector; the second quick connector has a second annular groove on its inner side, and a sealing ring is provided inside it.

8. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 1, characterized in that: The photocatalytic-capacitor deionization coupling element includes a Cu mesh / Cu2Se / CN photocatalytic film, a non-woven fabric isolation layer, a CNT carbon fiber film and a steel mesh stacked sequentially, with the photocatalytic surface of the Cu mesh / Cu2Se / CN photocatalytic film facing the light-transmitting element. Preferably, the thickness of the nonwoven fabric isolation layer is 0.5-1.5 mm.

9. The photocatalytic treatment device for chlorophenol-based organic wastewater according to claim 1, characterized in that: The second quick-connect fitting has a drain pipe slot at one end.

10. A photocatalytic treatment method for chlorophenol-based organic wastewater, characterized in that: Includes the following steps: The photocatalytic treatment device for the chlorophenol organic wastewater is assembled. The photocatalytic-capacitor deionization coupling element includes a Cu mesh / Cu2Se / CN photocatalytic membrane, a non-woven fabric isolation layer, a CNT carbon fiber membrane and a steel mesh stacked in sequence. The photocatalytic surface of the Cu mesh / Cu2Se / CN photocatalytic membrane faces the light-transmitting element. The light source is directed towards the Cu mesh / Cu2Se / CN photocatalytic membrane through the light-transmitting element; Connect the Cu mesh / Cu2Se / CN photocatalytic membrane and the steel mesh to a power source, making the Cu mesh / Cu2Se / CN photocatalytic membrane the cathode and the steel mesh and CNT carbon fiber membrane the anode; The organic wastewater to be treated is introduced into the first pipe through the second pipe. The organic wastewater undergoes photocatalytic-capacitor deionization treatment as it flows out of the photocatalytic-capacitor deionization element. The treated organic wastewater flows out from the outlet. Preferably, the CNT carbon fiber membrane is composed of aminated carbon nanotubes, polyacrylonitrile, and / or N,N The dimethylformamide spinning solution is electrospun into a fiber membrane, which is then pre-oxidized in air at 200-250℃ for 2 h, and then carbonized in nitrogen at 750-850℃ for 1-3 h to obtain the final product. Preferably, the Cu mesh / Cu2Se / CN photocatalytic membrane is prepared by reacting sodium hydroxide, sodium borohydride and selenium powder in water to generate a precursor solution; The clean steel mesh was immersed in the precursor solution and reacted for 1-3 h. After being removed and dried under vacuum, the steel mesh loaded with Cu2Se was obtained. Carbon nitride powder, ethyl cellulose, polyvinylidene fluoride, terpineol, anhydrous ethanol and acetic acid are mixed and ground into a uniform slurry. The slurry is then coated onto the surface of the Cu mesh / Cu2Se and dried and cured to obtain the final product. Preferably, the mass ratio of carbon nitride powder, ethyl cellulose, polyvinylidene fluoride, terpineol, anhydrous ethanol and acetic acid is (0.05-0.2):(0.01-0.1):(0.01-0.1):(0.5-2):(0.3-1.5):(0.02-0.1).

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