Method for removing pollutants in water by activating percarbonate through electrochemical cathode

Abstract

The invention discloses a method for removing pollutants in water by activating percarbonate through an electrochemical cathode, which comprises the following steps: adding electrolyte and percarbonate into sewage to be treated, uniformly stirring to obtain reaction liquid, and then introducing the reaction liquid into an electrochemical reactor for electrolytic reaction, after the reaction is finished, the treatment on the pollutants in the water is finished. According to the method, percarbonate is excited to generate various active oxygen species such as hydroxyl free radicals (. OH), superoxide free radicals # imgabs 0 # singlet oxygen (1O2) and carbonate free radicals # imgabs 1 # through an electrochemical activation means, and the diversity and concentration level of the active oxide species are remarkably improved. The technology not only can efficiently inactivate antibiotic-resistant bacteria in the water body, but also can synchronously degrade halogenated organic matters and enable high-concentration organic matters to form polymers so as to be settled, filtered and removed. And the degradation or polymerization of pollutants in the sewage can be completed only under the input of relatively small energy, so that the method has a good application prospect and considerable technical popularization potential.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to a method for removing pollutants in water by electrochemical cathode activation of percarbonate. Background Art

[0002] With the acceleration of industrialization and urbanization, the types of pollutants in water bodies are becoming increasingly complex. In particular, antibiotic-resistant bacteria (ARBs), halogenated organic pollutants (such as 2,4-dichlorophenoxyacetic acid and polychlorinated biphenyls), and high-concentration organic pollutants pose an increasingly severe threat to the aquatic environment. Traditional water treatment technologies face multiple challenges in dealing with these pollutants.

[0003] When treating antibiotic-resistant bacteria (ARB), the traditional activated sludge method has low efficiency in removing ARB and is prone to secondary pollution of activated sludge; membrane bioreactors have problems such as serious membrane fouling, high cost and insufficient disinfection effect. Conventional disinfection technologies such as chlorine disinfection, ultraviolet disinfection and ozone disinfection can partially remove ARB, but they require high-dose operation and have the risk of bacterial resurrection (chlorine / ultraviolet disinfection), disinfection by-products (chlorine / ozone disinfection) and high energy consumption. When treating halogenated organic pollutants, physical adsorption methods (such as activated carbon) only transfer pollutants and have the risk of secondary release; chemical oxidation methods (Fenton reagent, ozone oxidation) rely on strong acidic conditions or high concentrations of oxidants, resulting in iron sludge by-products or high energy consumption; biodegradation methods are inefficient for highly halogenated pollutants and microorganisms are easily inhibited by toxicity. When treating high-concentration organic pollutants, existing technologies generally have problems such as low efficiency, high cost, secondary pollution risk and complex processes.

[0004] In this context, advanced oxidation technologies (AOPs) based on free radical reactions have attracted much attention due to their efficient degradation capabilities. Among them, sodium percarbonate (SPC) has become a new oxidant due to the environmentally friendly properties of its decomposition products (Na2CO3 and H2O2) and its wide pH adaptability. However, existing SPC activation technologies still have significant drawbacks:

[0005] For example, the method of zero-valent iron activation percarbonate degradation of organic pollutants in water proposed in CN119390228A requires the addition of excessive iron when activating percarbonate, which easily leads to secondary pollution of iron ions and increased costs. Akash et al. use the Na, B and O co-doped g-CN / polypyrrole carbon black (CCNP) composite hydrogel prepared by in-situ crosslinking method to improve the tetracycline degradation efficiency by free radical generation, but the direct activation performance of non-metallic materials on SPC is limited, relying on visible light conditions and low light energy utilization, and the rapid recombination of photogenerated electron-hole pairs easily leads to catalyst deactivation. In addition, ozone catalysis SPC has technical bottlenecks such as low mass transfer efficiency, by-product toxicity risk and high energy consumption.

[0006] In summary, there is an urgent need to develop a new green, efficient and low-cost SPC activation method to achieve efficient wastewater treatment. Summary of the Invention

[0007] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for removing pollutants in water by electrochemical cathode activation of percarbonate, so as to solve the problems of low activation efficiency, high cost, easy environmental pollution and disadvantageous for sewage treatment of the existing percarbonate activation methods.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0009] A method for removing pollutants in water by electrochemical cathode activation of percarbonate comprises the following steps: adding electrolyte and percarbonate to wastewater to be treated and stirring evenly to obtain a reaction solution, then passing the reaction solution into an electrochemical reactor for electrolysis reaction, and completing the treatment of pollutants in the water after the reaction is completed.

[0010] Furthermore, the concentration of percarbonate in the reaction solution is 0.5 to 15 mM.

[0011] Furthermore, when used to inactivate antibiotic-resistant bacteria and / or degrade halogenated organic pollutants in wastewater, the percarbonate concentration is 0.5 to 2 mM. When the percarbonate concentration reaches 1.5 mM, increasing the percarbonate concentration does not change the bacterial removal rate after 20 minutes, so the preferred percarbonate concentration is 1 to 1.5 mM.

[0012] Furthermore, when used for polymerization and sedimentation to remove high-concentration organic matter in sewage, the concentration of the percarbonate is 14 to 16 mM.

[0013] Furthermore, during the electrolysis reaction, the current intensity is 4 to 17 mA / cm 2 .

[0014] Furthermore, the current intensity is 4.15~12.55mA / cm 2 .

[0015] Furthermore, the percarbonate is sodium percarbonate.

[0016] Furthermore, the electrolyte is sodium sulfate.

[0017] Furthermore, the concentration of the electrolyte is 40-50 mM.

[0018] Furthermore, in the electrochemical reactor, the cathode is a carbon-based electrode, a titanium electrode, a stainless steel electrode, or a metal composite electrode, and the anode is a graphite electrode, a metal electrode, or a metal composite electrode. The cathode is preferably a carbon-based electrode. Carbon-based materials have a high specific surface area, a rich pore structure, and excellent electrical conductivity, providing a large number of active sites and significantly enhancing reaction activity.

[0019] The reaction mechanism of the present invention is as follows:

[0020] Na2CO3·1.5H2O2→Na2CO3+1.5H2O2

[0021] The following reaction occurs at the anode:

[0022] 2H2O-4e - →O2+4H +

[0023]

[0024] The following reaction occurs at the cathode:

[0025] H2O+2e - →H2+2OH -

[0026] H2O2+2e - → OH+OH -

[0027]

[0028]

[0029] From the above reaction formula, it is not difficult to see that under the action of the external electric field, the cathode H2O and Get electrons to generate OH and Reactive oxygen species (ROS) such as O2 generate electrons Then further transformed into 1 O2 reactive oxygen species, in the anode, The redox reaction between OH and OH will also produce a certain amount of OH - and and other reactive oxygen species.

[0030] These ROS generated at the anode and cathode can effectively inactivate antibiotic-resistant bacteria in wastewater and degrade halogenated organic pollutants and aggregated high-concentration organic pollutants. When inactivating antibiotic-resistant bacteria, ROS attack their cell membranes, cytoplasm, and other cellular structures, thereby inactivating them. When degrading halogenated organic pollutants, these ROS cause the halogenated organic matter to undergo dehalogenation reactions, followed by gradual decomposition and mineralization. When aggregating high-concentration organic pollutants, these ROS attack the organic matter to generate organic free radicals (R·), which in turn trigger free radical chain polymerization reactions. Under conditions of high organic concentrations, the high collision frequency between free radicals and monomers drives polymerization, resulting in the precipitation of large organic molecules through aggregate precipitation, ultimately achieving the removal of high-concentration organic matter through solid-liquid separation. However, in the absence of electrical current, percarbonate produces little or no reactive oxygen species, resulting in poor inactivation of antibiotic-resistant bacteria in water. Furthermore, it is also less effective in degrading halogenated organic matter and aggregate precipitation of high-concentration organic pollutants in wastewater.

[0031] It can be seen that there is a synergistic effect between electrochemical activation and percarbonate, and the removal efficiency of pollutants in water by this coupled oxidation system is much higher than that of the percarbonate system alone.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The present invention provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which stimulates percarbonate to produce hydroxyl radicals (·OH) and superoxide radicals by electrochemical activation. Singlet oxygen ( 1 O2), carbonate radicals The technology can not only effectively inactivate antibiotic-resistant bacteria in water bodies, but also simultaneously degrade halogenated organic matter and remove high-concentration organic pollutants through polymerization and sedimentation. During the reaction, through the coordinated optimization of the electrolyte system and reaction conditions, the stringent requirements of the traditional Fenton system for a strong acidic environment were broken through, and long-term stable operation under neutral to weakly acidic conditions was achieved. Furthermore, through the precise control of current density and the selection of functional electrode materials, the free radical species (such as ·OH, 1 O2) and reaction pathways to achieve highly adaptable degradation of complex pollutant systems. In addition, this method also abandons the Fe 2+ The addition of reagents avoids the generation of iron-containing sludge and the risk of secondary pollution from metal ions from the source, and is both environmentally friendly and cost-effective.

[0034] 2. Compared with the potential risk of microbial regeneration in traditional disinfection processes, the system constructed by the present invention can achieve persistent inactivation of antibiotic-resistant bacteria, providing effective protection for microbial risk control in water environments. In particular, the system exhibits excellent comprehensive treatment efficiency under acidic, neutral, and alkaline conditions: it maintains high efficiency in inactivating antibiotic-resistant bacteria, while achieving deep degradation of halogenated organic pollutants and effective polymerization of high-concentration organic matter. Experimental data show that the effect of the initial pH value on the degradation efficiency of target pollutants is significantly reduced, showing a wide pH adaptability, thereby greatly expanding the system's operating pH window and enhancing the adaptability of the technology to various scenarios.

[0035] 3. The method of the present invention features a simple operational process, utilizes an environmentally friendly percarbonate reagent, and eliminates the risk of secondary pollution. The percarbonate activity can be efficiently stimulated through low-energy electrochemical activation, demonstrating excellent degradation efficiency for a wide range of water pollutants. Optimized process parameters simultaneously reduce both power consumption and percarbonate dosage, significantly lowering operating costs while maintaining treatment efficiency. This provides significant technical and economic advantages for large-scale engineering applications and holds broad prospects for industrialization and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The inactivation curves of resistant bacteria in different systems in Example 1, Comparative Example 1 and Comparative Example 2 of the present invention, wherein C: activated carbon fiber; E: electrolysis; SPC: sodium percarbonate; N t is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours at different electrolysis times, N0 is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours when the electrolysis time is 0;

[0037] Figure 2 The effect of different current intensities on the inactivation of resistant bacteria in Examples 1-4 of the present invention; N t is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours at different electrolysis times, N0 is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours when the electrolysis time is 0;

[0038] Figure 3 This is a graph showing the effect of different SPC concentrations on the inactivation of resistant bacteria in Examples 1 and 5-8 of the present invention; N t is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours at different electrolysis times, N0 is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours when the electrolysis time is 0;

[0039] Figure 4The degradation curves of 2,4-D in different systems in Example 9, Comparative Example 3, and Comparative Example 4 of the present invention are shown, wherein C: activated carbon fiber; E: electrolysis; SPC: sodium percarbonate; C is the concentration of 2,4-D in the sample at different electrolysis times; C0 is the concentration of 2,4-D at the initial state;

[0040] Figure 5 This is a graph showing the polymerization degradation of phenol, a high-concentration organic pollutant, in Example 10 of the present invention; C is the concentration of phenol in the sample at different electrolysis times; C0 is the concentration of phenol at the initial state;

[0041] Figure 6 is the bactericidal effect curve under different pH conditions in Example 1, Example 11, and Example 12; N t is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours at different electrolysis times, N0 is the number of bacteria on the sample coated on the plate after incubation at 37°C for 24 hours when the electrolysis time is 0;

[0042] Figure 7 is the degradation curve of 2,4-D under different pH conditions in Example 9, Example 13, and Example 14; C is the concentration of 2,4-D in the sample at different electrolysis times; and C0 is the concentration of 2,4-D in the initial state. DETAILED DESCRIPTION

[0043] The specific implementation methods of the present invention are further described in detail below with reference to specific examples.

[0044] The numerical ranges herein are understood to specifically disclose every intervening value between the upper and lower limits of the range. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in that stated range is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

[0045] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art. Although the present invention has only described preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail. As used herein, "comprising", "including", "having", "containing", etc. are all open-ended terms, meaning including but not limited to.

[0046] Unless otherwise specified, the experimental methods used in the present invention are all conventional methods.

[0047] Unless otherwise specified, the materials, reagents, etc. used in the present invention can be purchased or synthesized by known methods.

[0048] The quantitative tests in the present invention were repeated three times and the results were averaged.

[0049] 1. Implementation

[0050] Example 1

[0051] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate. The initial concentration of bacteria in the sewage is 10 7 ~10 8 CFU / mL, the reactor is a cylindrical flow-through electrochemical reactor with a chamber inside. The reactor has an outer radius of 10 cm and a thickness of 4.8 cm, and an inner chamber with a diameter of 4 cm and a depth of 1.5 cm.

[0052] The specific steps include:

[0053] The treated sewage was stirred thoroughly with a magnetic stirrer at a speed of 800 r / min. Then, sodium sulfate was added to the sewage under stirring conditions to a concentration of 50 mM. The pH of the sewage was adjusted to 7 (using NaOH and H2SO4). After that, sodium percarbonate solution was added to the sewage to a concentration of 1.5 mM. Finally, the obtained sewage solution was injected into the electrochemical reactor, and a DC power supply was started. With activated carbon fiber as the cathode and titanium-plated platinum electrode as the anode, the current intensity was 12.55 mA / cm 2 The wastewater was electrolyzed under the condition of 100℃. During the reaction, samples were taken at regular intervals, i.e., 0, 2, 5, 10, 15, and 20 minutes, with 1 mL sampled each time. The samples were then subjected to 10 1 , 10 2 , 10 3 , 10 4 , 10 5 The dilution is done in a gradient manner. In the specific operation, each dilution is performed by diluting the sample after the previous dilution until a dilution of 10 is obtained. 5 Take 0.1mL of the sample solution and dilute it 10 times. 5 After coating the plate with 100 times the sample solution, place it in a 37℃ oven and culture it for 24 hours. Then read the number of bacteria at each time point and record it. Then calculate the bacteria removal rate and draw a time-bacteria removal logarithm curve, as shown in the figure. Figure 1 、 2 As shown in Figure 3, in this embodiment, the bacteria removal rate is 7.48 log after 20 minutes.

[0054] Example 2

[0055] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is similar to that of Example 1, except that the current intensity is 4.18 mA / cm 2 .

[0056] like Figure 2 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 2.84 log.

[0057] Example 3

[0058] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is similar to that of Example 1, except that the current intensity is 8.37 mA / cm 2 .

[0059] like Figure 2 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 6.48 log.

[0060] Example 4

[0061] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is similar to that of Example 1, except that the current intensity is 16.74 mA / cm 2 .

[0062] like Figure 2 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 7.48 log.

[0063] Example 5

[0064] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the concentration of sodium percarbonate in the sewage reaches 0.5 mM.

[0065] like Figure 3 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 3.57 log.

[0066] Example 6

[0067] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the concentration of sodium percarbonate in the sewage reaches 1.0 mM.

[0068] like Figure 3 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 4.68 log.

[0069] Example 7

[0070] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the concentration of sodium percarbonate in the sewage reaches 2.0 mM.

[0071] like Figure 3 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 7.48 log.

[0072] Example 8

[0073] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the concentration of sodium percarbonate in the sewage reaches 4.0 mM.

[0074] like Figure 3 As shown, in this embodiment, the bacterial removal rate is 7.48 log after 10 minutes, and remains unchanged at 7.48 log after 20 minutes.

[0075] Example 9

[0076] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate. The initial concentration of 2,4-D (Chinese name: 2,4-dichlorophenoxyacetic acid) in the sewage is 25 mg / L. The reactor is a cylindrical flow-through electrochemical reactor with a chamber inside. The reactor has an outer radius of 10 cm and a thickness of 4.8 cm. The internal chamber has a diameter of 4 cm and a depth of 1.5 cm.

[0077] The specific steps include:

[0078] The wastewater to be treated was stirred thoroughly with a magnetic stirrer at a speed of 800 r / min. Then, sodium sulfate was added to the wastewater under stirring conditions to make the concentration of sodium sulfate in the wastewater reach 50 mM. The pH of the wastewater was adjusted to 7 (using NaOH and H2SO4). After that, sodium percarbonate solution was added to the wastewater to make the concentration of sodium percarbonate in the wastewater reach 1.25 mM. Finally, the obtained wastewater solution was injected into the electrochemical reactor, and a DC power supply was started. With activated carbon fiber as the cathode and titanium-plated platinum electrode as the anode, the current intensity was 12.55 mA / cm 2 Wastewater was electrolyzed under a 10-minute, 20-minute, 30-minute, 40-minute, 50-minute, and 60-minute intervals. 1 mL of sample was taken at regular intervals. Each 1 mL sample was filtered through a 0.22 μm PTFE membrane and then placed into a liquid phase vial containing 0.2 mL of methanol. All samples were stored at 3°C prior to testing.

[0079] Record the concentration of 2,4-D in each sample of this example, calculate the removal rate of 2,4-D, and draw a time-pollutant removal curve. Figure 4 、 7 As shown, in this embodiment, the removal rate of 2,4-D is about 95.7%.

[0080] Example 10

[0081] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as Example 6, except that the sewage contains high concentrations of organic pollutants (phenol is an example of a pollutant) and the concentration of sodium percarbonate in the sewage reaches 15mM.

[0082] Record the concentration changes of organic pollutants in the sewage before and after treatment in this example and observe the aggregation of organic pollutants. Figure 5 As shown, in this embodiment, after 60 minutes of treatment, the removal rate of organic pollutants is about 95.05%.

[0083] Example 11

[0084] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the pH of the sewage is adjusted to 3.

[0085] like Figure 6 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 7.58 log.

[0086] Example 12

[0087] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 1, except that the pH of the sewage is adjusted to 11.

[0088] like Figure 6 As shown, in this embodiment, the bacteria removal rate after 20 minutes was 7.61 log.

[0089] Example 13

[0090] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 9, except that the pH of the sewage is adjusted to 3.

[0091] like Figure 7 As shown, in this embodiment, the removal rate of 2,4-D is about 85.14%.

[0092] Example 14

[0093] This embodiment provides a method for removing pollutants from water by electrochemical cathode activation of percarbonate, which is mainly the same as that of Example 9, except that the pH of the sewage is adjusted to 11.

[0094] like Figure 7 As shown, in this embodiment, the removal rate of 2,4-D is about 82.31%.

[0095] Comparative Example 1

[0096] This comparative example provides a method for removing pollutants from water, which is mainly the same as Example 1, except that no electricity is applied during the reaction.

[0097] like Figure 1 As shown, in this comparative example, the bacteria removal rate was 1.10 log after 20 min.

[0098] Comparative Example 2

[0099] This comparative example provides a method for removing pollutants from water, which is mainly the same as Example 1, except that sodium percarbonate is not added to the sewage.

[0100] like Figure 1 As shown, in this comparative example, the bacteria removal rate was 0.36 log after 20 min.

[0101] Comparative Example 3

[0102] This comparative example provides a method for removing pollutants from water, which is mainly the same as Example 6, except that sodium percarbonate is not added to the sewage.

[0103] like Figure 4 As shown, in this comparative example, the removal rate of 2,4-D is about 20.71%.

[0104] Comparative Example 4

[0105] This comparative example provides a method for removing pollutants from water, which is mainly the same as Example 6, except that no electricity is applied during the reaction.

[0106] like Figure 4 As shown, in this comparative example, the removal rate of 2,4-D is about 36.65%.

[0107] 2. Data Analysis

[0108] Figure 1 The inactivation curves of resistant bacteria in different systems in Example 1, Comparative Example 1 and Comparative Example 2 of the present invention, wherein C: activated carbon fiber; E: electrolysis; SPC: sodium percarbonate; Figure 1It can be seen that under the same conditions, the present invention improves the removal of Escherichia coli by 7.12 log compared with the inactivation of antibiotic-resistant bacteria by the electrochemical system alone, and improves the removal of Escherichia coli by 6.38 log compared with the inactivation of antibiotic-resistant bacteria by the percarbonate system alone. It can be seen that the effect of the present invention is significantly better than other treatment methods, and it is not a simple superposition of the effects of the two. This is because there is a coupling effect between electricity / percarbonate, which greatly enhances the utilization rate of the agent and improves the efficiency of generating active oxidative species.

[0109] Figure 2 The effect of different current intensities on the inactivation of resistant bacteria in Examples 1-4 of the present invention is shown in FIG. Figure 2 It can be seen that under the same conditions, as the current intensity increases, the reaction system has a better effect on inactivating resistant bacteria. When the current density reaches 12.55 mA / cm 2 After that, with the increase of current intensity, the inactivation effect of resistant bacteria for 20 min is no longer enhanced, which shows that the optimal current density is 12.55 mA / cm 2 .

[0110] Figure 3 Graph showing the effect of different percarbonate concentrations on the inactivation of resistant bacteria in Examples 1 and 5-8 of the present invention; Figure 3 It can be seen that under the same conditions, as the SPC concentration increases, the reaction system has a better effect on inactivating resistant bacteria. When the SPC concentration reaches 1.5 mM, the inactivation effect of resistant bacteria in 20 min no longer increases with the increase of SPC concentration. It can be seen that the SPC concentration is preferably 1.5 mM.

[0111] Figure 4 The degradation curves of 2,4-D by different systems in Example 9, Comparative Example 3 and Comparative Example 4 of the present invention are shown, wherein C: activated carbon fiber; E: electrolysis; SPC: sodium percarbonate; Figure 1 It can be seen that under the same conditions, the degradation effect of the present invention is significantly better than that of the electrochemical system alone and the percarbonate system alone. It can be seen that there is a coupling effect between electricity and percarbonate, which greatly enhances the degradation effect of pollutants.

[0112] Figure 5 is the polymerization degradation curve of phenol in Example 10 of the present invention; Figure 5 It can be seen that the reaction system of the present invention can effectively remove high-concentration organic pollutants. After 60 minutes of treatment, the removal rate of organic pollutants is about 95.05%.

[0113] Figure 6 The bactericidal effect curves under different pH conditions in Example 1, Example 11 and Example 12 are shown in FIG. Figure 6 It can be seen that when sewage treatment is carried out, under acidic, neutral and alkaline conditions, the bacterial removal in 20 minutes can reach 7.48 log or above. It can be seen that when the reaction system of the present invention is used to inactivate antibiotic-resistant bacteria in sewage, the effect of the initial pH value on the inactivation efficiency of the target bacteria is significantly weakened, and the system of the present invention exhibits a wide pH adaptability.

[0114] Figure 7 The degradation curves of 2,4-D under different pH conditions in Example 9, Example 13 and Example 14 are shown in FIG. Figure 7 It can be seen that during wastewater treatment, the removal rate of 2,4-D remained stable at over 80% under acidic, neutral, and alkaline conditions. This indicates that when the reaction system of the present invention is used to degrade organic matter in wastewater, the effect of the initial pH value on the degradation efficiency of the target pollutant is significantly reduced, demonstrating that the system of the present invention exhibits broad pH adaptability.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present invention that do not depart from the purpose and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for removing pollutants from water by electrochemical cathode activation of percarbonate, characterized in that: The method comprises the following steps: adding electrolyte and percarbonate to the wastewater to be treated and stirring evenly to obtain a reaction solution, and then passing the reaction solution into an electrochemical reactor for electrolysis reaction. After the reaction is completed, the pollutants in the water are treated.

2. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 1, wherein The concentration of percarbonate in the reaction solution is 0.5-15 mM.

3. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 2, wherein: When used to inactivate antibiotic-resistant bacteria in sewage and / or degrade halogenated organic pollutants in sewage, the concentration of the percarbonate is 0.5-2 mM.

4. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 2, wherein: When used for polymerization and sedimentation to remove high-concentration organic matter in sewage, the concentration of the percarbonate is 14-16 mM.

5. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 1, wherein During the electrolysis reaction, the current intensity is 4 to 17 mA / cm 2 .

6. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 5, wherein: Current intensity is 4.15~12.55mA / cm 2 .

7. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 1, wherein: The percarbonate is sodium percarbonate.

8. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 1, wherein: The electrolyte is sodium sulfate.

9. The method for removing pollutants in water by electrochemical cathode activation of percarbonate according to claim 1, wherein: The concentration of the electrolyte is 40-50 mM.

10. The method for removing pollutants from water by electrochemical cathode activation of percarbonate according to claim 1, characterized in that: In the electrochemical reactor, the cathode is a carbon-based material electrode, a titanium material electrode, a stainless steel electrode or a metal composite electrode, and the anode is a graphite electrode, a metal electrode or a metal composite electrode.

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