Advanced sewage treatment method based on Magneli-phase Ti4O7 reactive electrochemical membrane

Abstract

The invention provides a sewage advanced treatment method based on a Magneli phase Ti4O7 reactive electrochemical membrane, which comprises the following steps: taking secondary effluent of a municipal sewage treatment plant as a sewage source, pre-filtering, and injecting the sewage into an open type electrochemical reactor; arranging a Magneli-phase Ti4O7 reactive electrochemical membrane at the center of the electrochemical reactor as an anode, arranging a stainless steel mesh at the outer side of the anode as a cathode, and respectively connecting the anode and the cathode to a positive electrode and a negative electrode of a direct-current stabilized power supply; and pumping out the sewage in the electrochemical reactor at a set flow rate and re-injecting the sewage to form a cross-flow circulating mode, applying constant current density to carry out electrochemical oxidation reaction, and taking the effluent after circulating treatment as the advanced treatment effluent. Compared with the prior art, the current efficiency is high, the ARGs removal capacity is high, the antibiotic degradation performance is excellent, secondary pollution is avoided, and an efficient and low-cost solution is provided for advanced sewage treatment.

Description

Technical Field

[0001] This invention relates to the field of electrochemical water treatment technology, and in particular to a method for deep wastewater treatment based on a Magnéli phase Ti4O7 reactive electrochemical membrane. Background Technology

[0002] With the widespread use of antibiotics, antibiotic resistance genes (ARGs) have become an emerging environmental pollutant. Traditional biological treatment processes in wastewater treatment plants are generally ineffective at removing antibiotics, and only a small amount is metabolized, with the majority entering the environment through wastewater discharge. This can even accelerate the spread of ARGs within wastewater treatment plants. As a major producer and consumer of antibiotics, China faces a high environmental risk from ARGs. Therefore, developing a technology to effectively remove this type of pollutant is urgently needed.

[0003] Electrochemical oxidation methods have been widely studied due to their high efficiency and ease of operation. However, traditional electrode materials have many limitations: SnO2 and PbO2 doped electrodes pose environmental toxicity risks due to the release of heavy metals (such as Sb and Pb); while boron-doped diamond (BDD) electrodes offer excellent performance, their high cost limits their application in large-scale wastewater treatment. Magnéli phase titanium oxide (especially Ti4O7) combines the conductivity of metals with the chemical stability of ceramics and possesses a high oxygen evolution potential, making it an ideal electrode material. However, traditional plate electrodes are limited by diffusion mass transfer, and there is still room for improvement in treatment efficiency.

[0004] In summary, developing a method to efficiently remove antibiotics and ARGs from secondary effluent using a porous Magnéli phase Ti4O7 reactive electrochemical membrane combined with crossflow mode to enhance mass transfer has become an important direction in the field of advanced water treatment. Summary of the Invention

[0005] To address the above technical problems, this invention discloses a wastewater deep treatment method based on a Magnéli phase Ti4O7 reactive electrochemical membrane. By utilizing the convective mass transfer advantage of porous electrodes, the current efficiency is significantly improved, antibiotics are effectively degraded, and ARGs are reduced. This solves the technical problems of high electrode material cost, high risk of heavy metal precipitation, and low mass transfer efficiency of traditional plate electrodes in existing electrochemical oxidation technologies.

[0006] The technical solution adopted by this invention is as follows: A method for advanced wastewater treatment based on a Magnéli phase Ti4O7 reactive electrochemical membrane includes the following steps: Step S1: Using secondary effluent from a municipal wastewater treatment plant as the wastewater source, the wastewater is pre-filtered and then injected into an open electrochemical reactor. Step S2: A Magnéli phase Ti4O7 reactive electrochemical membrane is placed at the center of the electrochemical reactor as the anode, and a stainless steel mesh is placed outside the anode as the cathode, keeping the electrode spacing constant; the anode and cathode are connected to the positive and negative terminals of a DC regulated power supply, respectively. Step S3: The wastewater in the electrochemical reactor is extracted at a set flow rate and re-injected to form a cross-flow circulation mode, so that the wastewater flows through the cathode and anode pores in sequence. Step S4: Adjust the DC regulated power supply to apply a constant current density for the electrochemical oxidation reaction; monitor the voltage drift during the reaction process in real time to maintain a constant current; the effluent after circulation treatment is the deep-treated effluent. In this step, hydroxyl radicals generated on the anode surface are used to oxidize and degrade antibiotics, resistance genes, and organic matter in the wastewater to achieve the purpose of water treatment.

[0007] This technical solution utilizes a Magnéli phase Ti4O7 reactive electrochemical membrane and a stainless steel mesh as the anode and cathode, respectively. The porous electrode structure enables convective mass transfer of pollutants, overcoming the mass transfer limitations of traditional electrochemical systems. The Ti4O7 reactive electrochemical membrane has low internal resistance (approximately 14.2 Ω) and good conductivity. The degradation mechanism is clear; EPR confirms that hydroxyl radicals (•OH) play a dominant role, meaning the main degradation mechanism is oxidation dominated by hydroxyl radicals (•OH), including benzene ring hydroxylation, amino oxidation, and direct attack of pollutant molecules by •OH. Compared with traditional treatment methods, this invention demonstrates superior performance in removing trace organic pollutants and ARGs, and high antibiotic removal efficiency.

[0008] As a further improvement of the present invention, the Magnéli phase Ti4O7 reactive electrochemical membrane is a porous ceramic electrode prepared by high-temperature hydrogen reduction method, with a pore size of 0.5 μm to 2.0 μm and an electrode spacing of 1.5 to 2.5 mm between the anode and cathode. Further, the electrode spacing between the anode and cathode is 2 mm. Further, the effective reaction area of ​​the Magnéli phase Ti4O7 reactive electrochemical membrane is 130 cm². 2 ~140cm 2 .

[0009] As a further improvement of the present invention, in step S4, the current density is 0.70 mA / cm². 2 ~10.90mA / cm 2 Furthermore, the current density is 5.80 mA / cm². 2 ~10.90mA / cm 2 .

[0010] As a further improvement of the present invention, when the secondary effluent contains sulfamethoxazole (SMX), the current density is 10.50–10.90 mA / cm². 2 Furthermore, the current density is 10.90 mA / cm². 2 .

[0011] When treating secondary effluent containing sulfamethoxazole (SMX), apply 10.90 mA / cm. 2 At a given current density and after a reaction time of 240 minutes, the removal rate of SMX can reach 75%–80%. At 5.80 mA / cm 2 At the specified current density, the removal rate of typical ARGs such as qnrS, aac (6')-Ib-cr, and tetM in wastewater is higher than 98%, with the removal rate of aac (6')-Ib-cr reaching 100%. At the same time, it significantly reduces the relative abundance of host bacteria of ARGs such as Proteobacteria and Bacteroidetes.

[0012] Furthermore, the method of this invention has a good removal effect on organic pollutants in secondary effluent, at 5.80 mA / cm³. 2 At a given current density, after a reaction time of 240 minutes, the total organic carbon (TOC) removal rate of wastewater can reach over 40%, and the UV... 254 The removal rate can reach over 59%; at 10.90 mA / cm² 2 At current density, the TOC removal rate can reach 43.22%, and the UV... 254 The removal rate can reach 60.47%.

[0013] As a further improvement of the present invention, in step S3, a peristaltic pump is used to extract and re-inject wastewater from the electrochemical reactor at a set flow rate. Driven by the peristaltic pump, the wastewater flows from the reactor body to the electrode interface, enhancing the contact between the pollutants and the anode surface through convective mass transfer.

[0014] As a further improvement of the present invention, the Magnéli phase Ti4O7 reactive electrochemical film is prepared by the following steps: Rutile TiO2 powder is added to an isopropanol aqueous solution, followed by the addition of polyethylene oxide binder. The mixture is then pressed into a tubular shape and sintered in air at 1000-1100°C for 18-24 hours, followed by reduction sintering in a hydrogen atmosphere at 1000-1100°C for 3-6 hours.

[0015] As a further improvement of the present invention, the amount of the polyethylene oxide binder is 5 wt% of the mass of the TiO2 powder and the isopropanol aqueous solution, and the sintering temperature in air and hydrogen atmosphere is 1050°C.

[0016] As a further improvement of the present invention, in the isopropanol aqueous solution, the volume ratio of isopropanol to [the other component] is 1:1.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: First, the electrode material exhibits excellent performance and produces no secondary pollution. The Magnéli phase Ti4O7 reactive electrochemical film used combines high conductivity, strong corrosion resistance, and high oxygen evolution potential. No heavy metal doping occurs during the preparation process, and no heavy metal precipitation occurs during the reaction, thus avoiding secondary pollution. Compared to BDD electrodes, Ti4O7 electrodes have lower preparation costs and are more suitable for large-scale engineering applications. Second, it has high mass transfer efficiency and improved current efficiency. The Ti4O7 electrode adopts a porous tubular structure and is combined with a peristaltic pump-driven cross-flow circulation mode, which allows wastewater to quickly reach the anode surface through convection. This overcomes the diffusion mass transfer limitation of traditional plate electrodes, greatly improves the contact efficiency between pollutants and the electrode, and thus improves the current efficiency of electrochemical oxidation. Third, the pollutant removal effect is comprehensive and efficient. Through the dominant oxidation effect of hydroxyl radicals, it can simultaneously achieve highly efficient removal of antibiotics, organic pollutants, and ARGs. The removal rate of SMX can reach 75%–80%, and the removal rate of typical ARGs is higher than 98%. TOC and UV... 254 The removal effect is significant, solving the problem that traditional processes are not effective in removing trace organic pollutants and ARGs. Fourth, it disrupts the transmission pathways of ARGs, resulting in low environmental risk. The method of this invention can not only directly oxidize and degrade ARGs, but also reduce the abundance of ARGs host bacteria by disrupting bacterial cell structure, thereby reducing the spread of ARGs from the source and significantly reducing the risk of ARGs exposure in the aquatic environment. Fifth, it is easy to operate, highly controllable, and has great potential for engineering applications. The entire treatment process combines electrochemical oxidation with circulating flow. The equipment structure is simple, and the treatment efficiency can be controlled by adjusting the current density. During the reaction process, only voltage drift needs to be monitored in real time and the current needs to be kept constant. Operation and maintenance are simple, making it suitable for large-scale advanced treatment of secondary effluent from urban wastewater treatment plants. Attached Figure Description

[0018] Figure 1 These are characterization images of the Magnéli phase Ti4O7 reactive electrochemical film prepared in Example 1 of this invention; wherein, (a) is a SEM morphology image, (b) is an XRD pattern, (c) is an XPS full spectrum, and (d) is a Ti2p XPS pattern.

[0019] Figure 2 This is a schematic diagram of the structure of the electrochemical reactor in Embodiment 2 of the present invention.

[0020] Figure 3 This is a graph showing the change of SMX in the secondary effluent over time under different current densities in Embodiment 5 of the present invention.

[0021] Figure 4 The TOC and UV levels in the secondary effluent under different current densities in Embodiment 5 of this invention are... 254 The graph shows the changes over time; where (a) is the TOC change graph and (b) is the UV change graph. 254 Change diagram.

[0022] Figure 5 These are diagrams showing the ARGs removal effect and microbial community analysis in the secondary effluent under different current densities in Example 5 of the present invention; wherein, (a) is a diagram showing the AGRs removal effect, and (b) is a diagram showing the microbial community analysis.

[0023] The attached figures are labeled as follows: 1-DC regulated power supply, 2-peristaltic pump, 3-Magnéli phase Ti4O7 porous tube, 4-stainless steel mesh. Detailed Implementation

[0024] The preferred embodiments of the present invention will be described in further detail below.

[0025] A method for advanced wastewater treatment based on a Magnéli phase Ti4O7 reactive electrochemical membrane includes the following steps: Step 1: Using secondary effluent from a municipal wastewater treatment plant as the wastewater source, after pre-filtration to remove large particulate matter, the wastewater is injected into an open cylindrical electrochemical reactor. Step 2: Place a Magnéli phase Ti4O7 porous tube as the anode in the center of the reactor, and place a stainless steel mesh as the cathode on the outside of the anode, keeping the electrode spacing constant. Step 3: Connect the anode and cathode to the positive and negative terminals of the DC regulated power supply, respectively; Step 4: Start the peristaltic pump to extract and re-inject the wastewater in the reactor at a set flow rate, forming a cross-flow circulation mode, so that the wastewater flows sequentially through the stainless steel mesh cathode and the Ti4O7 anode pores. Step 5: Adjust the DC power supply and apply a constant current density to carry out the electrochemical oxidation reaction; Step 6: Monitor voltage drift during the reaction process in real time and maintain constant current; Step 7: Utilize the hydroxyl radicals generated on the anode surface to oxidize and degrade antibiotics, resistance genes, and organic matter in the wastewater; Step 8: The effluent after reactor circulation treatment is the deep-treated effluent.

[0026] Furthermore, in step two, the Magnéli phase Ti4O7 porous tube is a porous ceramic electrode prepared by high-temperature hydrogen reduction, with a pore size of 0.5 μm to 2.0 μm and an effective reaction area of ​​137 cm². 2 The distance between the anode and the cathode is 2 mm.

[0027] Furthermore, the applied current density in step five is in the range of 0.70 mA / cm². 2 ~10.90mA / cm 2 .

[0028] Furthermore, in step two, a stainless steel mesh (39mm in diameter and 130mm in length) is used as the cathode to surround the anode.

[0029] The following description uses specific examples to illustrate the point.

[0030] Example 1 This embodiment describes the preparation of a Magnéli phase Ti4O7 reactive electrochemical membrane, including the following steps: Step S10: Weigh rutile TiO2 powder and isopropanol aqueous solution (isopropanol to water volume ratio is 1:1), and place them in a mixing and stirring device for preliminary mixing; Step S20: Add 5 wt% polyethylene oxide binder to the mixture from step S10 and continue stirring until the mixture is homogeneous to form a viscous slurry. Step S30: The viscous slurry is pressed into a tubular blank under a pressure of 20 MPa. The blank has a diameter of 35 mm and a length of 130 mm. The tubular blank is placed in a muffle furnace and sintered at 1050 °C for 24 hours in an air atmosphere to complete the blank shaping. Then, the sintered tubular blank is transferred to a tube furnace, hydrogen is introduced into the furnace, and reduction sintering is carried out at 1050 °C for 4 hours in a hydrogen atmosphere. Step S40: After reduction sintering is completed, turn off the hydrogen gas and allow the tube furnace to cool naturally to room temperature to obtain the finished black Magnéli phase Ti4O7 porous tube.

[0031] The obtained samples were characterized, and the results are as follows: Figure 1 As shown, the pore size of the Ti4O7 electrode is 0.5μm to 2.0μm, the effective reaction area is 137cm², and the internal resistance is about 14.2Ω. XRD and XPS analyses confirmed that its main crystalline phase is Ti4O7, and it exhibits excellent conductivity and chemical stability.

[0032] Example 2 The Ti4O7 electrode prepared in Example 1 was used for the removal of sulfamethoxazole (SMX) from secondary effluent, comprising the following steps: (1) Collect secondary effluent from the secondary sedimentation tank of the urban sewage treatment plant and pre-filter it with 20-30μm filter paper to remove large particulate suspended impurities; (2) such as Figure 2 As shown, an open cylindrical electrochemical reactor was constructed, with the Magnéli phase Ti4O7 porous tube 3 prepared in Example 1 placed at the center of the reactor as the anode. The effective area of ​​the Ti4O7 reactive electrochemical membrane was 137 cm². 2 A stainless steel mesh 4 is placed outside the anode as the cathode. The stainless steel mesh has a diameter of 39mm and a length of 130mm to ensure that the distance between the anode and cathode is 2mm. (3) Connect the anode to the positive terminal of DC regulated power supply 1 and the cathode to the negative terminal of the power supply; (4) Inject 960 mL of pretreated secondary effluent and 200 mL of SMX standard solution into the reactor to prepare a treated water sample with an initial SMX concentration of 10 mg / L; (5) Start the peristaltic pump 2 to drive the water sample to form a through-flow circulation in the reactor, so that the water sample flows through the stainless steel mesh cathode and Ti4O7 anode pores in sequence; (6) Adjust the DC regulated power supply to apply 10.90 mA / cm 2 The electrochemical oxidation reaction was initiated with a constant current density, and the total reaction time was 240 minutes. During the reaction, the voltage change was monitored in real time, and the voltage drift was controlled between 3.87V and 3.91V to maintain a constant current density.

[0033] Samples were taken at 0, 60, 120, 180, and 240 minutes of reaction, and the concentration of SMX in the water samples was determined by high performance liquid chromatography (HPLC).

[0034] Test results: After 240 minutes of reaction, the removal rate of SMX in the water sample reached 78.02%. Free radical quenching experiments confirmed that hydroxyl radicals (…) OH) is the dominant active substance in the degradation of SMX. It is evident that the Ti4O7 reactive electrochemical membrane exhibits excellent removal efficiency for sulfonamide antibiotics under high current density.

[0035] Example 3 Based on Example 2, the reactor was used for experiments to remove organic pollutants from secondary effluent, including the following steps: (1) Collect secondary effluent from the secondary sedimentation tank of the urban sewage treatment plant, pre-filter it through 20-30 μm filter paper, and inject 1160 mL into the electrochemical reactor of Example 2; (2) Start the peristaltic pump to form a through-flow circulation, adjust the DC regulated power supply, and apply 5.80 mA / cm. 2 An electrochemical oxidation reaction was carried out at a constant current density for 240 minutes. (3) During the reaction, the voltage drift is controlled between 3.42V and 3.45V, and the current is kept constant; (4) Samples were taken at different time points during the reaction. The TOC concentration of the water samples was determined using a TOC-VCPH type total organic carbon analyzer, and the UV concentration of the water samples was determined using an ultraviolet spectrophotometer. 254 The concentration.

[0036] Test results: After a reaction time of 240 minutes, the TOC removal rate of the secondary effluent was 40.11%, and the UV removal rate was [missing information]. 254 The removal rate was 59.13%, indicating that under medium current density, this method can effectively remove organic pollutants from secondary effluent, achieving a certain degree of mineralization removal.

[0037] Example 4 Based on Example 2, using the reactor for the removal of antibiotic resistance genes (ARGs) and host bacteria from secondary effluent includes the following steps: (1) Collect secondary effluent from the secondary sedimentation tank of the urban sewage treatment plant, pre-filter it through 20-30 μm filter paper, and inject 1160 mL into the electrochemical reactor of Example 2; (2) Start the peristaltic pump to form a through-flow circulation, adjust the DC regulated power supply, and apply 5.80 mA / cm. 2 At a constant current density, an electrochemical oxidation reaction is carried out; (3) After the reaction was completed, water samples were collected and the DNA of microorganisms in the water samples was extracted. The relative abundance of ARGs such as qnrS, aac(6')-Ib-cr, and tetM was determined by qPCR technology, and the microbial community structure was analyzed by high-throughput sequencing technology.

[0038] Test results: qPCR detection showed that the relative abundance of intracellular ARGs was significantly reduced, the removal rates of qnrS and tetM were both higher than 98%, and the removal rate of aac(6')-Ib-cr reached 100%; high-throughput sequencing showed that the relative abundance of potential host bacteria of ARGs such as Proteobacteria and Bacteroidetes in the water sample was significantly reduced, and the bacterial cell structure was effectively destroyed.

[0039] It is evident that the method of this invention can not only remove chemical pollutants, but also efficiently remove biological pollutants (ARGs and bacteria), significantly reducing the risk of resistance gene transmission in the environment.

[0040] Example 5 Experiment on the effect of different current densities on pollutant removal.

[0041] Based on Example 2, 0.70 mA / cm was set respectively. 21.50mA / cm 2 3.60 mA / cm 2 5.80 mA / cm 2 8.80 mA / cm 2 10.90 mA / cm 2 Six current densities were used to treat secondary effluent according to the methods in Examples 2-4, and the SMX, TOC, and UV were measured at different current densities. 254 And the removal effect of ARGs.

[0042] Test results are as follows Figure 3 , Figure 4 and Figure 5 As shown, it can be seen that with the increase of current density, SMX, TOC, and UV... 254 The removal rate gradually increases, and the removal rate of ARGs gradually increases; when the current density is below 3.60 mA / cm³, the removal rate of ARGs gradually increases. 2 At that time, the pollutant removal efficiency was relatively low; when the current density reached 5.80 mA / cm², the efficiency was even lower. 2 At current densities of 10.90 mA / cm³, efficient removal of ARGs can be achieved (removal rate > 98%); 2 At this time, the removal efficiency of antibiotics and organic pollutants reaches its optimal level.

[0043] The above embodiments demonstrate that the method of the present invention can efficiently remove antibiotics, organic pollutants and antibiotic resistance genes from the secondary effluent of urban sewage treatment plants. It is also simple to operate, highly controllable, and suitable for large-scale engineering applications.

[0044] As can be seen from the above embodiments, the wastewater deep treatment method based on the Magnéli phase Ti4O7 reactive electrochemical membrane disclosed in this invention utilizes the porous microstructure to enhance the mass transfer of pollutants to the anode surface, and combines this with the hydroxyl radicals generated at a high oxygen evolution potential to achieve deep oxidation. Compared with existing plate electrodes or biological treatment technologies, this method exhibits excellent antibiotic degradation rate and ARGs reduction rate. Experimental results show that, under higher current densities, the TOC and UV levels in the secondary effluent are significantly reduced. 254 The removal rate increases with increasing current density, and it can effectively destroy bacterial cell structure, reduce ARGs host activity, and prevent their spread in the aquatic environment.

[0045] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for advanced wastewater treatment based on a Magnéli phase Ti4O7 reactive electrochemical membrane, characterized in that: Includes the following steps: Step S1: Using secondary effluent from a municipal wastewater treatment plant as the wastewater source, the wastewater is pre-filtered and then injected into an open electrochemical reactor. Step S2: A Magnéli phase Ti4O7 reactive electrochemical membrane is placed at the center of the electrochemical reactor as the anode, and a stainless steel mesh is placed outside the anode as the cathode, keeping the electrode spacing constant; the anode and cathode are connected to the positive and negative terminals of a DC regulated power supply, respectively. Step S3: The wastewater in the electrochemical reactor is extracted at a set flow rate and then re-injected to form a cross-flow circulation mode, so that the wastewater flows through the cathode and anode pores in sequence. Step S4: Adjust the DC regulated power supply and apply a constant current density to carry out the electrochemical oxidation reaction; monitor the voltage drift during the reaction process in real time and maintain a constant current; the effluent after circulation treatment is the deep-treated effluent.

2. The wastewater deep treatment method based on the Magneli phase Ti4O7 reactive electrochemical membrane according to claim 1, characterized in that: The Magnéli phase Ti4O7 reactive electrochemical membrane is a porous ceramic electrode prepared by high-temperature hydrogen reduction method, with a pore size of 0.5 μm to 2.0 μm and an electrode spacing of 1.5 to 2.5 mm between the anode and the cathode.

3. The wastewater deep treatment method based on the Magnéli phase Ti4O7 reactive electrochemical membrane according to claim 1, characterized in that: In step S4, the current density is 0.70 mA / cm². 2 ~10.90mA / cm 2 .

4. The wastewater deep treatment method based on the Magneli phase Ti4O7 reactive electrochemical membrane according to claim 3, characterized in that: In step S4, the current density is 5.80 mA / cm². 2 ~10.90mA / cm 2 .

5. The wastewater deep treatment method based on the Magnéli phase Ti4O7 reactive electrochemical membrane according to claim 4, characterized in that: When the secondary effluent contains sulfamethoxazole, the current density is 10.50–10.90 mA / cm². 2 .

6. The wastewater deep treatment method based on the Magneli phase Ti4O7 reactive electrochemical membrane according to claim 4, characterized in that: In step S3, a peristaltic pump is used to extract the wastewater from the electrochemical reactor at a set flow rate and then re-inject it.

7. The wastewater deep treatment method based on the Magnéli phase Ti4O7 reactive electrochemical membrane according to claim 1, characterized in that: The Magneli phase Ti4O7 reactive electrochemical membrane was prepared using the following steps: Rutile TiO2 powder is added to an isopropanol aqueous solution, followed by the addition of polyethylene oxide binder. The mixture is then pressed into a tubular shape and sintered in air at 1000-1100°C for 18-24 hours, followed by reduction sintering in a hydrogen atmosphere at 1000-1100°C for 3-6 hours.

8. The wastewater deep treatment method based on the Magneli phase Ti4O7 reactive electrochemical membrane according to claim 7, characterized in that: The amount of the polyethylene oxide binder is 5 wt% of the mass of the TiO2 powder and the isopropanol aqueous solution, and the sintering temperature in air and hydrogen atmosphere is 1050℃.

9. The wastewater deep treatment method based on the Magneli phase Ti4O7 reactive electrochemical membrane according to claim 7, characterized in that: In the isopropanol aqueous solution, the volume ratio of isopropanol to water is 1:1.

Images