Method for synergistically degrading organic pollutants by low consumption of persulfate through electro-enhanced activation of anode and cathode

Abstract

The application discloses an electro-enhanced activation persulfate oxidation method for removing organic pollutants with low consumption through cooperation of anode and cathode, uses LaCoO3 modified Ti4O7 active electrochemical film rich in oxygen vacancy as an anode, and uses in-situ grown nano-carbon modified carbon felt as a cathode to construct an anode-cathode cooperative activation persulfate system, achieves 100% removal of sulfamethoxazole within 37.3 seconds, and the energy consumption is only 0.0015 kWh / m 3 ·order. The technology meets the demand of high flux (1061 L / m 2 ·h) for complete degradation of pollutants, and can also realize deep mineralization (89%) of pollutants at slightly lower flux (212.22 L / m 2 ·h). Compared with the prior art, the bipolar activation persulfate system of the application has the characteristics of significantly improving the space-time efficiency by using bipolar multi-active sites, solving the problems of low wastewater treatment capacity, poor mineralization and high energy consumption of the single-pole system, and efficiently treating actual marine aquaculture wastewater and domestic sewage. The application has excellent pollutant removal and mineralization efficiency, wide pH application range, good stability, long service life, and wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of electro-enhanced activation of persulfate technology and wastewater treatment, specifically to a method for low-consumption degradation of organic pollutants using electro-enhanced activation of persulfate with synergistic anode and cathode. Background Technology

[0002] Water pollution and clean water shortages, especially those caused by organic pollutants, pose significant threats to ecosystems and public health, hindering global sustainable development initiatives. Rapid global industrialization has exceeded initial projections of water demand, driving research into innovative wastewater treatment technologies. In recent years, electro-enhanced persulfate activation technology has seen increasingly widespread application in wastewater treatment. Utilizing an electric field to improve the activation efficiency of persulfate can combine the advantages of two treatment technologies, complementing their shortcomings. This addresses the issues of narrow pH application range and secondary pollution caused by iron sludge in electrocatalysis, while overcoming the disadvantages of poor catalyst recovery and reuse in persulfate catalysis. Electro-enhanced persulfate activation technology encompasses both anodic and cathodic activation methods; however, regardless of whether anodic or cathodic activation is used, the idle state of the electrodes leads to resource waste. Using only anodes or cathodes for wastewater treatment results in low treatment capacity, poor mineralization efficiency, and high energy consumption. In practical applications, single-electrode activation is limited by a narrow pH application range, interference from coexisting substances, and poor stability. Therefore, it is crucial to develop an electrochemical water treatment technology that co-activates persulfate with anode and cathode to avoid wasting electrodes and maximize the mineralization efficiency of organic pollutants and wastewater treatment capacity.

[0003] Traditional planar electrodes suffer from low processing efficiency, limited reaction area, and poor mass transfer performance. Membrane electrodes, on the other hand, can fully utilize their surface and internal space to participate in the electrochemical reactions during membrane filtration, thus increasing the reactive area. During the penetration of organic pollutants through porous membrane electrodes, increased pressure can promote turbulence on the electrode surface, accelerating the mass transfer rate of pollutants and persulfate molecules, thereby improving pollutant removal and mineralization efficiency. Magnéli phase Ti4O7 (TO) is an ideal anolyte active electrochemical membrane (REM) due to its high conductivity, good corrosion resistance, economy, stability, and non-toxicity. However, pure TO exhibits poor electron migration ability and electrochemical reactivity due to its high charge transfer resistance and lack of reaction sites. Perovskite oxide LaCoO3 (LCO) can increase reaction sites and improve electrochemical activity; oxygen-vacancy (Vo)-modified TO active electrochemical membranes (LCVTO REM) show promising potential as anodes. On the cathode side, research focuses on improving wastewater purification efficiency and reducing costs. Carbon felt (CF) is widely used due to its high conductivity, porous structure, and good mass transfer performance; however, pure CF has limited persulfate activation capacity. Introducing nano-carbon can enhance the charge transfer process and improve pollutant removal efficiency. The synergistic effect of LCVTO REM anodes and nano-carbon modified CF (C / CF) will improve treatment capacity, enhance mineralization efficiency, and save energy, achieving efficient and economical water purification. Summary of the Invention

[0004] This invention addresses the shortcomings of existing single-electrode activated persulfate degradation technologies for organic pollutants, such as low treatment capacity, poor mineralization efficiency, and high energy consumption. It utilizes a novel LCVTO REM anode, rich in oxygen vacancies, prepared using a TO active electrochemical membrane with high mass transfer efficiency and stable physicochemical properties as a substrate. This anode, combined with a modified C / CF cathode, forms a synergistic anode-cathode activation system for treating polluted water. Co and Vo on the LCVTO REM anode are the active sites. After persulfate is adsorbed onto the Co sites, there are two main reaction pathways. The first pathway involves the spontaneous decomposition of adsorbed *HSO5 (the main component of persulfate) into *OH and *SO4. - Groups, as shown in reaction formula (1). In the presence of Vo, persulfate passes through *HSO5 and *SO4. - The oxygen atom of the group is adsorbed onto the Co site, resulting in partial *OH conversion and desorption, and subsequently generating sulfate radicals (SO4) through reaction (2)-(3). •- ) and hydroxyl ( • OH). The second pathway involves the adsorbed persulfate desorbing H* and decomposing into SO5. •- (Reaction (4)), SO5 •- Singlet oxygen is rapidly formed through reaction (5).1 O2). Furthermore, Vo is readily converted into reactive oxygen species (O2) through electron transfer. o × ), and with HSO5 - Generate through reaction (6) coupling 1 O2. For cathode persulfate activation, nano-carbon serves as the reactive site. The oxygen-containing functional groups (–OH, –COOH) on the carbon electrode surface and at edge defects enhance the electron transfer process and provide catalytic active sites. During the reaction, persulfate adsorbed on the nano-carbon can react with another persulfate molecule to form… 1 O2 is used to degrade pollutants. Compared to single-electrode activated persulfate technology, the anode-cathode synergistic technology removes organic pollutants by efficiently generating active oxygen species at multiple active sites on the anode and cathode under the same or lower energy consumption conditions, significantly improving spatiotemporal efficiency. Furthermore, the use of a filtration reactor not only solves the bottlenecks of low current efficiency and poor mass transfer in planar electrodes, but also reduces the adsorption or deposition of pollutants on the membrane electrode surface through electrostatic repulsion between charged pollutants and the membrane electrode. Simultaneously, pollutants enriched on and inside the membrane electrode can be effectively degraded and mineralized by the active substances generated during the reaction, alleviating membrane fouling and enhancing the self-cleaning ability of the membrane electrode, thereby achieving the goal of ultra-high efficiency, low energy consumption, high throughput, and strong stability in wastewater purification.

[0005] HSO5 - → SO4 •- + • OH (1)

[0006] Co 2+ + HSO5 - + Vo → Co 3+ + SO4 •- + H + + O o × (2)

[0007] Co 2+ + HSO5 - + Vo + H2O → Co 3+ + SO4 2- + • OH + 2H + + O o × (3)

[0008] HSO5 - → SO5 •- + H + → 1 O2 (4)

[0009] SO5 •- + SO5 •- → SO4 2- + 1 O2 (5)

[0010] O o × + HSO5 - → HSO5 - + 1 O2 (6)

[0011] This invention is achieved through the following technical solution:

[0012] A method for low-consumption degradation of organic pollutants using electro-enhanced activation of persulfate with synergistic anode and cathode is characterized by the use of a dual-electrode system, including an anode, a cathode, electrolyte-containing organic wastewater, persulfate, and a filtration reactor for organic pollutant degradation. The anode is an oxygen-vacancy-rich LaCoO3 (LCO) modified Ti4O7 (TO) active electrochemical membrane (LCVTO REM) placed at the top of the filtration reactor. The cathode is an in-situ grown nano-carbon modified carbon felt (C / CF) placed at the bottom of the reactor. Organic wastewater containing persulfate flows into the reactor from bottom to top. The two electrodes are connected by wires and current is applied, and organic matter degradation is carried out in a continuous flow mode.

[0013] LCVTO REM anodes are prepared by the following method:

[0014] Step 1) The perovskite LCO powder prepared by the sol-gel method was transferred to a sodium borohydride (NaBH4) solution and stirred for 4 h, wherein the mass ratio of LCO to NaBH4 was 1:1 to 1:5. The material was then washed and vacuum dried to obtain LCO rich in Vo (LCO-Vo, LCV).

[0015] Step 2) Mix the LCV product from Step 1) with TO powder evenly, use paraffin oil as a binder, press into tablets and calcine at 800°C in an inert atmosphere to obtain the LCVTO REM anode.

[0016] The C / CF cathode is prepared by the following method:

[0017] Step 1) Dissolve citric acid monohydrate in deionized water and disperse by ultrasonication, then transfer the solution to a 70°C water bath and stir for 3 hours;

[0018] Step 2) Immerse the carbon felt (CF) in the concentrated solution of Step 1) until it is completely absorbed, dry it, and then calcine it at 800°C for 3 h under an inert atmosphere to obtain the modified C / CF cathode.

[0019] The above-mentioned method for low-consumption degradation of organic pollutants by electro-enhanced activation of persulfate through synergistic anode and cathode is characterized in that the persulfate is permonosulfate or perdisulfate with a concentration of 0.5-2.0 mM.

[0020] The above-mentioned method for low-consumption degradation of organic pollutants by electro-enhanced activation of persulfate through synergistic anode and cathode is characterized in that the influent flow rate of organic wastewater is 2.5-15.0 mL / min.

[0021] The above-mentioned method for low-consumption degradation of organic pollutants by electro-enhanced activation of persulfate through synergistic anode and cathode is characterized in that the applied current is 1-4 mA.

[0022] This invention has the following outstanding features:

[0023] (1) The synergistic activation of persulfate by anode and cathode significantly outperforms the single-electrode activation of persulfate system in removing organic pollutants. For example, sulfamethoxazole (SMX) was removed with 100% efficiency within a residence time of 37.3 seconds and a rate constant of 15.84 min. -1 These figures are 12 times and 21 times higher than those achieved by using only the anode and cathode for activation, respectively.

[0024] (2) The energy consumption of this anode-cathode synergistic activation persulfate system is extremely low (0.0015 kWh / m³). 3 • order), which is only 7.9% and 4.6% of that of anode or cathode activation alone.

[0025] (3) This anode-cathode synergistic technology meets the requirements of high throughput (1061 L / m). 2 The requirement for complete degradation of organic pollutants (·h) can be met at a slightly lower flux (212.22 L / m³). 2 Deep mineralization of organic pollutants (89%) was achieved under h).

[0026] (4) The anode-cathode synergistic technology has excellent performance in removing organic pollutants, a wide pH range, good mechanical stability and long service life, which broadens the types and scope of wastewater treatment.

[0027] (5) This anode-cathode synergistic technology can efficiently remove organic pollutants from marine aquaculture wastewater and domestic sewage, and has broad application prospects for both high-conductivity and low-conductivity wastewater. Attached Figure Description

[0028] Figure 1 These are scanning electron microscope images of the LCVTO REM anode prepared according to the present invention;

[0029] Figure 2 These are scanning electron microscope images of the C / CF cathode prepared according to the present invention;

[0030] Figure 3 This is a schematic diagram of the reaction of the anode-cathode synergistic activation persulfate system constructed in this invention;

[0031] Figure 4 This is a comparison diagram of the degradation effects of the synergistic activation of persulfate system by anode and cathode constructed in this invention and the separate activation of persulfate system by anode and cathode.

[0032] Figure 5 A comparison of the energy consumption of the synergistic activation persulfate system constructed by the anode and cathode of this invention and the single activation persulfate system by the anode and cathode for the degradation of sulfamethoxazole.

[0033] Figure 6 This is a comparison diagram of the active species generated by the synergistic anode and cathode system constructed in this invention and the individual anode and cathode systems;

[0034] Figure 7 This is a graph showing the effect of LCVTO REM anolysate-activated persulfate system with different oxygen vacancy contents prepared in this invention on the degradation of sulfamethoxazole;

[0035] Figure 8 This is a comparison chart of the performance of the anodic-cathode synergistic system constructed in this invention in degrading sulfamethoxazole through different processes;

[0036] Figure 9 This is a graph showing the degradation effect of sulfamethoxazole and the total organic carbon mineralization of the anode-cathode synergistic activation persulfate system constructed in this invention at different flow rates.

[0037] Figure 10 This is a diagram showing the effect of the anodic and cathodic synergistic activation persulfate system constructed in this invention on the decomposition of sulfamethoxazole at different pH values;

[0038] Figure 11 This is a diagram illustrating the effect of the anode-cathode synergistic activation persulfate system constructed in this invention on the degradation of various pollutants;

[0039] Figure 12 This is a graph showing the effect of the anode-cathode synergistic activation persulfate system constructed in this invention on the degradation of sulfamethoxazole after 20 repeated uses and the persulfate utilization rate.

[0040] Figure 13 The graph shows the sulfamethoxazole removal effect, total organic carbon mineralization effect, and persulfate utilization rate of the anodic and anode synergistic activation persulfate system constructed in this invention after 12 hours of continuous operation.

[0041] Figure 14 This is a diagram showing the effect of the anode-cathode synergistic activation persulfate system constructed in this invention on the treatment of sulfamethoxazole, total organic carbon, and chemical oxygen demand in marine aquaculture wastewater;

[0042] Figure 15 This is a diagram showing the effect of the anode-cathode synergistic activation persulfate system constructed in this invention on the treatment of sulfamethoxazole, total organic carbon, and chemical oxygen demand in domestic sewage. Detailed Implementation

[0043] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0044] Implementation Case 1

[0045] The preparation method of LCVTO REM anode is as follows: 1 mM La(NO3)3·6H2O, 1 mM Co(NO3)2·6H2O and 2 mM citric acid monohydrate were heated and stirred in a water bath at 70°C for 4 h to form a wet gel. The gel was then dried in an oven at 60°C and calcined in a muffle furnace at 800°C for 2 h to obtain LCO powder. The obtained LCO powder was transferred to a sodium borohydride (NaBH4) solution and stirred for 4 h, wherein the mass ratio of LCO to NaBH4 was 1:4. The solution was then washed with deionized water and ethanol and vacuum dried to obtain LCO rich in Vo (LCO-Vo, LCV). 15 mg of the obtained product was mixed evenly with 10 g of TO powder, and 2 mL of paraffin oil was added as a binder. The resulting mixture was placed in a stainless steel mold with a diameter of 3.8 cm and a pressure of about 8 MPa was applied to obtain a disc with a thickness of 2.5 mm. The disc was then calcined at 800°C for 6 h in an inert atmosphere to obtain the LCVTO REM anode. Scanning electron microscopy revealed that the large, bulky substrate was TO, and the small particles distributed on it were LCV (see results). Figure 1 The C / CF cathode was prepared as follows: 2.5 g of citric acid monohydrate was dissolved in 30 mL of deionized water, ultrasonically dispersed for 20 min, and then the solution was transferred to a 70℃ water bath and stirred for 3 hours. Carbon felt (CF) was immersed in the above concentrated solution until complete absorption, dried at 60℃ for 12 h, and then calcined at 800℃ for 3 h under an inert atmosphere to obtain the modified C / CF cathode. Scanning electron microscopy revealed uniformly distributed carbon nanoparticles on the CF (see results). Figure 2 ).

[0046] This implementation example uses the activation of permonosulfate (PMS) as an example to demonstrate the effectiveness of the anode-cathode synergistic activation persulfate system. The prepared LCVTO REM anode and C / CF cathode were placed at the top and bottom of a filter reactor, respectively. A solution containing 1.5 mM PMS and pH 7, and containing 20 mg / L sulfamethoxazole (SMX, the target pollutant), flowed from bottom to top into the reactor at a flow rate of 12.5 mL / min. The two electrodes were connected by wires, and a current of 2 mA was applied. Organic matter degradation was carried out in a continuous flow mode. (See [link to relevant documentation]). Figure 3 In contrast, the anode activation system alone used a titanium mesh as the cathode, which lacks persulfate activation properties, and the cathode activation system alone used a titanium mesh as the anode. This synergistic anode-cathode activation system for persulfate removal exhibited ultra-high efficiency in SMX removal, achieving 100% SMX removal within a residence time of 37.3 seconds. In contrast, the anode and cathode activation systems alone could only remove approximately 64% and 36% of SMX, respectively, and the reaction rate constant of the synergistic anode-cathode system was 15.84 min. -1 The values ​​were for a single anode (1.31 min). -1 ) and cathode (0.75 min) -1 The activation was 12-fold and 21-fold higher. (See results) Figure 4 ).

[0047] Implementation Case 2

[0048] The steps in Implementation Case 2 are basically the same as those in Implementation Case 1. The energy consumption (EEO) for removing an order of magnitude of SMX from 1 cubic meter of water is calculated using formula (7). The resulting anode-cathode synergistic system has extremely low power consumption, only 0.0015 kWh / m³. 3 • order, while the energy consumption of the individual anodic activation and cathodic activation systems is 0.0189 and 0.0328 kWh / m², respectively. 3 • In order, the synergistic anode-cathode system achieved only 7.9% and 4.6% of the activation rates of either the anode or cathode alone (see results). Figure 5 ).

[0049] EEO (kWh / m 3 ·order) = 10 -3 × UI / [Qlog(C0 / C t (7)

[0050] Implementation Case 3

[0051] The steps for Implementation Case 3 are basically the same as those for Implementation Case 1, except that SMX is not added to the reaction solution. Please refer to [link / reference]. Figure 6 When using electron paramagnetic resonance (EPR) technology to investigate the mechanism of synergistic activation of persulfate by cathode and anode, the main active species detected were:• OH, SO4 •- and 1 O2 was also detected in the anolyte activated persulfate system. • OH, SO4 •- and 1 O2 and three active substances, and • OH and SO4 •- The signal strength is close to that of the anode-cathode synergistic system. In the cathode-activated system, extremely weak signals were observed. • OH and SO4 •- Signals and obvious 1 The O2 signal proves 1 O2 dominates the cathode system, and O2 •- It is almost non-existent in all three systems. Therefore, in the anode-cathode synergistic system, the anode primarily provides... • OH, SO4 •- and a part 1 O2, while the cathode mainly provides another part. 1 O2.

[0052] Implementation Case 4

[0053] The steps for Implementation Case 4 are basically the same as those for Implementation Case 1, except that the mass ratio of LCO to NaBH4 in the LCVTO REM anode preparation process is 1:1 to 1:5. Please refer to [link / reference]. Figure 7 When the LCO / NaBH4 mass ratio increased from 1:1 to 1:4, the removal rate of sulfamethoxazole increased from 72% to 100%. However, when the LCO / NaBH4 mass ratio was 1:5, the removal rate of SMX decreased slightly to 94%. Therefore, the LCVTO REM anode with an LCO / NaBH4 mass ratio of 1:4 showed the best effect in degrading sulfamethoxazole, and this ratio of anode was selected for subsequent experiments.

[0054] Implementation Case 5

[0055] The steps in Implementation Case 5 are basically the same as in Implementation Case 1, except that no current is applied during the persulfate activation process, and no persulfate is added during the electrocatalytic process. Please refer to [link to relevant documentation]. Figure 8 The electro-enhanced persulfate activation system described in this invention exhibits a synergistic effect between the electric field and persulfate. The electro-enhanced persulfate activation system can remove approximately 100% of sulfamethoxazole, which is far higher than that of the single persulfate activation process (~45%) and the single electrocatalytic process (~2%).

[0056] Implementation Case 6

[0057] The steps for Implementation Case 6 are basically the same as those for Implementation Case 1, except that the flow rates are set to 2.5 mL / min, 5.0 mL / min, 7.5 mL / min, 10.0 mL / min, 12.5 mL / min, and 15.0 mL / min, respectively. Please refer to [link / reference]. Figure 9 The anode-cathode synergistic activation system of persulfate described in this invention operates at a rate of 2.5 mL / min (212.22 L / m³). 2 •h) -12.5 mL / min (1061 L / m 2 At flow rates of up to 100% (·h), almost all (~100%) of the organic pollutant sulfamethoxazole can be removed, and at a flow rate of 15 mL / min, removal of over 86% can be achieved. The total organic carbon (TOC) mineralization rate decreases with increasing flow rate, but at a flow rate of 2.5 mL / min, 89% TOC removal can be achieved, achieving deep mineralization of the organic pollutant. Therefore, this anode-cathode synergistic technology meets the requirements for high throughput (1061 L / m³). 2 The requirement for complete degradation of organic pollutants (·h) can be met at a slightly lower flux (212.22 L / m³). 2 Deep mineralization of organic pollutants can be achieved under h).

[0058] Implementation Case 7

[0059] The steps for implementing Case 7 are basically the same as those for Case 1, except that the pH values ​​are set to 3, 4, 5, 7, 9, 10, 11, 12, 13, and 14 respectively. Please refer to [link / reference]. Figure 10 The anodic and cathodic synergistic activation persulfate system described in this invention can remove 100% of sulfamethoxazole at pH 4-14, and can achieve a removal rate of about 80% even under strongly acidic conditions (pH=3), proving that the anodic and cathodic synergistic activation persulfate system described in this invention has a wide pH range of applicability.

[0060] Implementation Case 8

[0061] The steps for implementing Case 8 are basically the same as those for Case 1, except that the target pollutants are 20 mg / L tetracyclines (tetracycline, oxytetracycline), sulfonamides (sulfamethoxazole, sulfadiazine), quinolones (norfloxacin, ciprofloxacin), and acetaminophen (chloramphenicol, florfenicol) antibiotics. Please refer to [link to relevant documentation]. Figure 11 The cathodic-anode synergistic activation persulfate system described in this invention can achieve a removal rate of over 90% for four classes (eight types) of antibiotics, indicating that the cathodic-anode synergistic activation persulfate system is applicable to the degradation and removal of a variety of antibiotics.

[0062] Implementation Case 9

[0063] The steps for Implementation Case 9 are basically the same as those for Implementation Case 1, except that the same LCVTO REM anode and the same C / CF cathode are used continuously. Please refer to [link / reference needed]. Figure 12 The anodic-anode synergistic activation persulfate system described in this invention can still remove more than 96% of sulfamethoxazole after being used 20 times under an applied current of 2 mA, indicating that the anodic-anode synergistic activation persulfate system has strong stability.

[0064] Implementation Case 10

[0065] The steps for implementing Case 10 are basically the same as those for Case 1, except that it runs continuously for 12 hours. Please refer to [link / reference]. Figure 13 The anodic and anode synergistic activation persulfate system described in this invention maintains a removal rate of approximately 97% for sulfamethoxazole after 12 hours of continuous operation. The total organic carbon mineralization rate and persulfate utilization rate also remain stable within 12 hours, indicating that the anodic and anode synergistic activation persulfate system can operate stably for a long time.

[0066] Implementation Case 11

[0067] The steps for Implementation Case 11 are basically the same as those for Implementation Case 1, except that 1 mg / L sulfamethoxazole, close to the environmental concentration, is added to the actual marine aquaculture wastewater. Please refer to [link / reference needed]. Figure 14 The cathodic-anode synergistic activation persulfate system described in this invention can efficiently treat actual marine aquaculture wastewater. The removal rate of sulfamethoxazole is maintained at about 100%, and the total organic carbon and chemical oxygen demand can also be removed by about 49% and 41%, respectively, indicating that the cathodic-anode synergistic activation persulfate system has the ability to efficiently treat actual marine aquaculture wastewater.

[0068] Implementation Case 12

[0069] The steps for Implementation Case 12 are basically the same as those for Implementation Case 1, except that 1 mg / L sulfamethoxazole, close to the environmental concentration, is added to the actual domestic sewage. Please refer to [link / reference needed]. Figure 15 The anodic-anode synergistic activation persulfate system described in this invention can efficiently treat actual domestic sewage. The removal rate of sulfamethoxazole is maintained at about 100%, and the total organic carbon and chemical oxygen demand can also be removed by about 50% and 61%, respectively, indicating that the anodic-anode synergistic activation persulfate system has the ability to efficiently treat actual domestic sewage.

Claims

1. A method for synergistically degrading organic pollutants by electro-enhanced activation of persulfate with cathode and anode, characterized in that: The application relates to a double electrode system for organic pollutant degradation, which comprises an anode, a cathode, organic wastewater containing electrolyte, persulfate and a filter reactor, wherein the persulfate is peroxymonosulfate or peroxodisulfate, the anode is a LaCoO3 (LCO) modified Ti4O7 (TO) active electrochemical membrane (LCVTO REM) rich in oxygen vacancies (Vo), is arranged at the top end of the filter reactor, the cathode is an in-situ grown carbon nanomaterial modified carbon felt (C / CF), is arranged at the bottom end of the reactor, the organic wastewater containing 0.5-2.0 mM persulfate flows into the reactor from bottom to top at a flow rate of 2.5-15.0 mL / min, wires are used to connect the two electrodes and apply a current of 1-4 mA, and the organic pollutant degradation is carried out in a continuous flow mode. The LCVTO REM anode is prepared by the following method: Step 1) the perovskite LCO powder prepared by a sol-gel method is transferred into a sodium borohydride (NaBH4) solution and stirred for 4 h, wherein the mass ratio of LCO to NaBH4 is 1:1 to 1:5, then the material is washed and vacuum dried to obtain LCO rich in Vo (LCO-Vo, LCV); Step 2) the product LCV of step 1) is uniformly mixed with TO powder, paraffin oil is used as a binder, tabletting is carried out, and the LCVTO REM anode is obtained by calcining at 800 DEG C in an inert atmosphere; The C / CF cathode is prepared by the following method: Step 1) citric acid monohydrate is dissolved in deionized water and ultrasonically dispersed, then the solution is transferred into a 70 DEG C water bath and stirred for 3 h; Step 2) carbon felt (CF) is immersed in the concentrated solution of step 1) until complete absorption, and the modified C / CF cathode is obtained after drying and calcining at 800 DEG C in an inert atmosphere for 3 h.

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