A method of electrochemically rejuvenating activated carbon

Abstract

This invention discloses a method for electrochemically regenerating activated carbon. Saturated activated carbon containing adsorbed organic matter is placed in an anode-cathode system containing a regeneration solution, and positioned on the cathode. Two peroxides, peroxide I and peroxide II, are added to the regeneration solution. Peroxide I is persulfate. The power is then turned on to initiate the reaction. After the reaction, the activated carbon is removed and dried to obtain regenerated activated carbon. This invention is simple to operate, requires no addition of metal ions, and employs a combination of technologies. These technologies work synergistically to simultaneously generate oxidizing and reducing active species, achieving efficient degradation and mineralization of pollutants. It also improves the regeneration effect of activated carbon, reduces the impact on its adsorption performance, and achieves harmless treatment of the regeneration solution. This method has significant practical application value and is of great importance in making activated carbon regeneration more economical and environmentally friendly.

Description

Technical Field

[0001] This invention belongs to the field of in-situ regeneration technology of adsorbents, specifically relating to a method for electrochemically regenerating saturated activated carbon for the adsorption of organic matter. Background Technology

[0002] Activated carbon is a widely used and highly efficient adsorbent material. Its surface has a large number of pores, resulting in a large specific surface area, allowing for rapid adsorption of small molecules. Due to its stable structure, high adsorption capacity, and easy regeneration, activated carbon is widely used in chemical, pharmaceutical, and environmental protection fields. In the environmental field, its main applications include the treatment of organic polluted water, industrial wastewater, and emergency response to water pollution, particularly in the treatment of various polluted water bodies, including phenol-containing wastewater and pharmaceutical wastewater. However, after a certain period of treatment with organic wastewater, activated carbon reaches adsorption saturation and can no longer adsorb organic pollutants. Direct disposal would result in resource waste, environmental pollution, and increased operating costs. Therefore, it is necessary to regenerate saturated activated carbon to restore its adsorption performance and allow for reuse.

[0003] Currently, commonly used industrial regeneration methods include thermal regeneration, ultrasonic regeneration, microwave regeneration, biological regeneration, and chemical regeneration. Thermal regeneration involves four stages: drying, evaporation, pyrolysis, and activation. From the perspective of the regeneration process, high temperatures alter the surface structure of activated carbon, damaging the surface properties of the adsorbent and leading to heat loss. Repeated regeneration can result in the loss of adsorption performance. For example, CN101987275B proposes a method and apparatus for adsorption-electrothermal desorption recovery of volatile organic compounds. This apparatus uses electricity to heat the adsorption cylinder, which uses activated carbon fiber as the adsorbent, and introduces an inert gas, allowing the VOCs adsorbed on the cylinder wall to desorb, thus achieving the purpose of device regeneration. For thermal desorption regeneration technology, increasing the desorption process temperature is a direct means to enhance its operating efficiency. However, this method is only suitable for in-situ regeneration of activated carbon adsorbing low-boiling-point organic compounds (VOCs), and has almost no effect on the regeneration of activated carbon adsorbing high-boiling-point organic compounds.

[0004] Electrochemical regeneration utilizes local pH changes and electrostatic repulsion to desorb pollutants from activated carbon, making it an effective desorption and regeneration method. However, this method cannot completely degrade and mineralize the desorbed pollutants, which instead accumulate in the regeneration solution, potentially posing a serious ecological hazard. Furthermore, the toxicity may increase with prolonged regeneration time. CN103435132A discloses an activated carbon fiber treatment method and apparatus for oily wastewater, using activated carbon fiber felt coated with titanium-based metal oxides as the anode and pure titanium metal as the cathode. Although the oil removal rate and regeneration effect can reach 95% and 97% respectively, the electrochemical oxidation only occurs on the anode surface. Limited by its mass transfer capacity, the mineralization ability is limited, and toxic intermediate products are generated. Moreover, achieving electrochemical oxidation requires high voltage, resulting in high energy consumption and significant electrode wear, hindering its widespread application. To enhance the oxidation capacity of electrochemical regeneration, electrolytes such as sodium chloride and hydrochloric acid can be used. The electrolysis products, including strong oxidizing substances like chlorine, hypochlorous acid, and hydroxyl radicals, enhance the ability to decompose and oxidize pollutants. For example, CN107055670A discloses an activated carbon adsorption-electrochemical regeneration method for treating recalcitrant organic wastewater. Air is introduced during electrolysis, and oxygen is reduced to H2O2 at the cathode. This H2O2 is further converted to ·OH by Mn or Fe catalysts on the activated carbon, improving the efficiency of organic matter oxidation and degradation. Although the formed three-dimensional electrode has a good regeneration effect on activated carbon for low-pressure nanofiltration (DF) concentrate after adsorption biological treatment processes, the ·OH generated is limited due to the limited H2O2 production, making it difficult to completely mineralize pollutants. Furthermore, it is only effective for activated carbon loaded with small amounts of Fe and Mn, and ineffective for activated carbon without Mn or Fe catalysts.

[0005] While advanced oxidation technologies (AEOs) alone are effective at degrading pollutants, they inevitably damage the structure and surface properties of activated carbon. Coupling with other technologies can mitigate this impact on the activated carbon structure. For example, CN113680340A discloses a low-temperature thermo-liquid phase in-situ regeneration method for powdered activated carbon based on continuous frequency conversion ultrasound / ozone solution coupling. Continuous frequency conversion ultrasound promotes ozone migration and mass transfer within the activated carbon pores, reducing the destructive effect of ozone on the activated carbon structure and achieving effective regeneration. However, the high construction and operation costs of continuous frequency conversion ultrasound technology hinder its widespread application. Existing AEOs may produce more biotoxic intermediates during the oxidation of certain pollutants (halogenated organic compounds), while advanced reduction technologies can generate reducing free radicals (e.g., hydroxyl radicals). aq - SO3 ·- H·O2 ·- (etc.) can effectively remove halogens and degrade ecotoxicity in regenerated solutions, but the reaction process requires the isolation of oxygen, which greatly limits its application range. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide an electrochemical method for regenerating activated carbon, which solves the problems of existing activated carbon regeneration methods, such as difficulty in simultaneously achieving activated carbon regeneration and pollutant degradation and mineralization, poor reproducibility of activated carbon regeneration efficiency, limited pollutant degradation and mineralization capacity, easy damage to activated carbon structure and surface properties, high energy consumption, high cost, and limited application scope.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] An electrochemical method for regenerating activated carbon involves placing activated carbon saturated with adsorbed organic matter into an anode-cathode system containing a regeneration solution, with the cathode positioned thereon; adding two peroxides, peroxide I and peroxide II, to the regeneration solution; wherein peroxide I is persulfate; then turning on the power supply to initiate the reaction, and continuously adding peroxide II during the reaction; after the reaction is complete, removing the activated carbon and drying it to obtain regenerated activated carbon.

[0009] Furthermore, the operating current density of the electrode system is 10–120 mA / cm². 2 .

[0010] Furthermore, the mass ratio of activated carbon, persulfate, and peroxide II is 1:5-50:5-50. Preferably, the mass ratio of activated carbon, persulfate, and peroxide II is 1:10-40:10-45.

[0011] Furthermore, the peroxide II includes one or more of hydrogen peroxide, peracetic acid, and alkali metal peroxides. Hydrogen peroxide is preferred.

[0012] Furthermore, the organic compound is one or more of the following: halogenated organic compounds, phenol, antibiotics, and endocrine disruptors.

[0013] Furthermore, during the reaction, peroxide II is continuously added in stages and at different rates. Preferably, the dropping rate of peroxide II in the first 0.5–1 hour is greater than the dropping rate for the remaining reaction time. This is because as the reaction proceeds, hydrogen peroxide may be blown off by the gas generated at the anode and cathode. If added all at once, it cannot be guaranteed that there will be a sufficient amount of hydrogen peroxide throughout the reaction, which would affect the regeneration effect of the activated carbon. Also, persulfate is consumed during the reaction, and there is relatively little persulfate in the reaction solution in the later stages. Therefore, less hydrogen peroxide is added in the later stages, and a slower dropping rate is used.

[0014] Furthermore, in the electrode system, the cathode is a metal electrode or a metal composite electrode, which serves as a support layer for placing the activated carbon to be regenerated; the anode is a metal electrode, a metal oxide electrode, a graphite electrode, or a metal composite electrode.

[0015] Furthermore, the activated carbon is a composite carbon-based or modified carbon-based material that has good adsorption properties for organic matter, such as powdered activated carbon, granular activated carbon, activated carbon fiber, or carbon felt. Activated carbon fiber is preferred.

[0016] Furthermore, the regenerated liquid is water, and may also include one or more electrolytes selected from sulfates, chlorides, and carbonates.

[0017] Advanced oxidation technology based on persulfate activates persulfate through methods such as heat, ultraviolet light, transition metal ions, carbon materials, electricity, and alkalis, thereby generating various reactive oxygen species to achieve oxidative degradation. It has attracted widespread attention due to its strong oxidizing power, stable treatment, and lack of secondary pollution. This invention regenerates saturated activated carbon by electrochemically coupling peroxides. This allows pollutants to rapidly desorb into the regeneration solution under the influence of an electric field and the formation of an alkaline diffusion layer through water electrolysis and hydrogen peroxide. Simultaneously, the electric field activates peroxides to continuously generate reactive species, thereby degrading and mineralizing pollutants in situ. Furthermore, placing the activated carbon at the cathode of the electrochemical regeneration system protects it from oxidative damage by oxidants and active substances, preserving its structural integrity and properties. Therefore, by electrocoupling persulfate and hydrogen peroxide, the activated carbon undergoes an in-situ regeneration reaction, restoring its adsorption capacity, degrading and mineralizing the adsorbed pollutants, and completing the in-situ regeneration of activated carbon. This achieves the goal of recycling, reduces operating costs, and solves the problems of resource waste and environmental pollution caused by discarded activated carbon. Furthermore, the method of this invention can restore the adsorption capacity of activated carbon and completely degrade and mineralize organic matter in the desorption solution, with the products being carbon dioxide, water, and inorganic ions, which is environmentally friendly and pollution-free.

[0018] In this invention, the regeneration principle of activated carbon using the electro / persulfate / hydrogen peroxide method can be divided into several aspects: first, electrodesorption, caused by local pH changes, local salinity changes, and electrostatic repulsion; second, electrooxidation, where organic matter is degraded through electron transfer at the anode surface; third, direct oxidation of peroxides; and fourth, indirect oxidation, utilizing the synergistic effect of electrochemistry with persulfate and hydrogen peroxide to simultaneously generate oxidizing and reducing reactive oxygen species (including...). HO · , HO2 - , 1 O2 and atomic hydrogen, etc., can be used to achieve efficient degradation and mineralization of recalcitrant organic matter.

[0019] The main reactions included are:

[0020] First, activated carbon is placed at the cathode, where OH- is generated during discharge. - Electrorepulsion causes organic compound R to desorb:

[0021] 2H2O+e - →2OH - +H2↑

[0022] H2O2+e - →HO · +OH -

[0023] ROH→RO - +H +

[0024] Second, persulfate and hydrogen peroxide in the electrolyte produce reactive oxygen species during electrocatalysis, which synergistically oxidize organic matter.

[0025] H2O→HO · +H + +e -

[0026] OH - →OH · +e -

[0027]

[0028]

[0029] XO2 (alkaline peroxide) + 2H2O → H2O2 + X(OH)2

[0030] ROOH(PAA) + H₂O → H₂O₂ + ROH

[0031] H2O2+e - →HO · +OH -

[0032]

[0033] Third, removal of organic matter R:

[0034]

[0035] Regeneration rate calculation: RE(%) = Q` / Q

[0036] In the formula: Q is the adsorption capacity (mg / g) of activated carbon when it first reaches adsorption saturation; Q' is the adsorption capacity (mg / g) of regenerated activated carbon when it reaches adsorption saturation.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. This invention utilizes electrochemical technology to couple persulfate and hydrogen peroxide to treat activated carbon saturated with adsorbed organic matter. This simultaneously achieves activated carbon regeneration and pollutant degradation and mineralization, with excellent reproducibility of activated carbon regeneration, consistently maintaining a reproducibility rate above 60%. Furthermore, the pollutant degradation and mineralization rate is high, consistently maintaining a removal rate above 95% and a mineralization rate above 90%. Compared to electrocoupled persulfate systems and separate electrolysis systems, this invention's electrocoupled persulfate and hydrogen peroxide system has lower energy consumption and lower cost. When treating the same mass and adsorption capacity of activated carbon, the energy consumption of this invention is half that of the electrocoupled persulfate system and one-tenth that of the separate electrolysis system, while also achieving a higher pollutant degradation and mineralization rate.

[0039] 2. The electrocatalytic double peroxide of this invention can simultaneously generate reducing and oxidizing active species. The addition of hydrogen peroxide, on the one hand, can form an alkaline diffusion layer at the cathode under the influence of an electric field, achieving rapid desorption of organic matter; on the other hand, it can catalyze the rapid production of persulfate. In the electrocatalytic dual peroxide system of this invention The yield is 18.2 times that of the electrocoupled persulfate system, which can maximize the degradation and mineralization of organic matter while reducing the amount of pharmaceutical input and saving costs.

[0040] 3. This invention, through cathodic protection, prevents activated carbon from being damaged by oxidants and active oxides during the regeneration process, thus solving the problem of severe structural damage to activated carbon in existing activated carbon regeneration methods. Attached Figure Description

[0041] Figure 1 This is a time-concentration curve of phenol in the regeneration solution in Example 1.

[0042] Figure 2 This is a time-concentration curve of TOC in the regenerated solution in Example 1.

[0043] Figure 3 This is a time-concentration curve of PFOS in the regenerated solution in Example 2.

[0044] Figure 4 This is a time-concentration curve of TOC in the regenerated solution in Example 2.

[0045] Figure 5 This is a time-concentration curve of phenol in the regeneration solution in Example 3.

[0046] Figure 6 For electro / persulfate / hydrogen peroxide systems and electro / persulfate systems Steady-state concentration comparison chart. Detailed Implementation

[0047] The specific embodiments of the present invention will be described in further detail below with reference to specific examples.

[0048] The numerical ranges in this invention should be understood to also specifically disclose each intermediate value between the upper and lower limits of the range. Each smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0049] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail. The terms “comprising,” “including,” “having,” “containing,” etc., as used herein are open-ended, meaning that they include but are not limited to.

[0050] Unless otherwise specified, the experimental methods used in this invention are all conventional methods.

[0051] Unless otherwise specified, all materials and reagents used in this invention can be purchased or synthesized by known methods.

[0052] In the quantitative experiments of this invention, each experiment was repeated three times, and the average value of the results was taken.

[0053] In the examples, phenol concentration was determined by liquid chromatography, perfluorooctane sulfonate (PFOS) concentration was determined by LC-MS, and TOC was determined by a TOC analyzer.

[0054] The formula for calculating the organic matter removal rate is shown in equation (1):

[0055]

[0056] In equation (1), C 有机物 Q represents the concentration of organic matter in the solution after regenerating activated carbon; Q represents the mass of organic matter adsorbed per gram of activated carbon after it becomes saturated with adsorbed organic matter; m represents the mass of activated carbon; and V represents the volume of the regeneration liquid.

[0057] The formula for calculating the mineralization rate is shown in equation (2):

[0058]

[0059] In equation (2), C TOC Q represents the concentration of TOC in the solution after regenerating activated carbon; Q represents the mass of organic matter adsorbed per gram of activated carbon after saturation; m represents the mass of activated carbon; V represents the volume of the regeneration liquid; N represents the number of carbon atoms in the pollutant; and M represents the molecular weight of the pollutant.

[0060] Example 1

[0061] A method for electrochemically regenerating saturated activated carbon includes the following steps:

[0062] (1) Preparation of saturated activated carbon fiber: 0.2g of activated carbon fiber was placed in 200mL of phenol solution with a concentration of 1600mg / L for 24h to adsorb, and then placed in an oven at 38℃ for 12h to obtain activated carbon fiber saturated with adsorption of phenol.

[0063] Based on the phenol concentration before and after adsorption, the volume of the phenol solution, and the mass of the activated carbon fiber before adsorption, the adsorption capacity of the activated carbon fiber was calculated to be 271.96 mg / g.

[0064] (2) Regeneration of saturated activated carbon fiber: Activated carbon fiber saturated with phenol adsorption is placed in an anode-cathode system and positioned at the cathode; 250 mL of regeneration solution (water) is added to the reaction chamber of the anode-cathode system, and potassium persulfate is added to the regeneration solution to achieve a concentration of 18 g / L; then hydrogen peroxide solution is added to the regeneration solution to achieve an initial hydrogen peroxide concentration of 0.4 mM / L. The activated carbon is then regenerated using a DC power supply (operating current density 28.57 mA / cm²). 2 During the regeneration process, 30wt% hydrogen peroxide solution is continuously added dropwise at different times and rates. The addition rate is 1.1mL / h for the first 40 minutes and 0.3mL / h for the next 260 minutes. After 5 hours of reaction, the activated carbon fiber is removed and dried at 38℃ for 12 hours to obtain the regenerated activated carbon fiber.

[0065] In this embodiment, both the anode and cathode are titanium-plated platinum electrode plates. In practical applications, the cathode can also be other metal electrodes or metal composite electrodes, used as a support layer for placing the activated carbon to be regenerated; the anode can also be other metal electrodes, metal oxide electrodes, graphite electrodes or metal composite electrodes.

[0066] The method of this invention is also applicable to the regeneration of powdered activated carbon, granular activated carbon, carbon felt, carbon nanotubes or graphene.

[0067] Treatment effect: After treating activated carbon fibers saturated with phenol using the method of this embodiment, the regeneration rate of activated carbon fibers was 80.77%. The curves showing the changes in phenol concentration and TOC concentration in the regeneration solution over time are shown below. Figure 1 , 2 As shown. By Figure 1 It can be seen that in this embodiment, the phenol concentration in the solution after 5 hours of regeneration is 4.22 mg / L. According to formula (1), the phenol removal rate is 98%. Figure 2 It can be seen that the TOC concentration in the solution after 5 hours of regeneration is 6.81 mg / L. According to formula (2), the mineralization rate of organic matter is 95%.

[0068] Example 2

[0069] A method for electrochemical regeneration of saturated activated carbon, the main steps of which are the same as in Example 1, except that the type of organic matter adsorbed is potassium perfluorooctane sulfonate (PFOS), and the adsorption capacity is 98.71 mg / g.

[0070] Treatment effect: The activated carbon fiber regeneration rate was 95.9%. The curves showing the changes in PFOS and TOC concentrations in the regeneration solution over time are shown below. Figure 3 , 4 As shown. By Figure 3 It can be seen that the PFOS concentration after 5 hours of regeneration is 0.33 mg / L. According to formula (1), the PFOS removal rate is 99%. Figure 4 It can be seen that the TOC concentration of the solution after 5 hours of regeneration is 1.08 mg / L. According to formula (2), the mineralization rate of organic matter is 93%.

[0071] Example 3

[0072] A method for electrochemically regenerating saturated activated carbon, the main steps of which are the same as in Example 1, except that the current density is 114.28 mA / cm². 2 The reaction time is 5 hours.

[0073] Treatment effect: The activated carbon fiber regeneration rate was 69.66%. Figure 5 As shown, in this embodiment, the phenol concentration in the solution after 5 hours of regeneration is 2.88 mg / L. According to formula (1), the phenol removal rate is 99%.

[0074] Example 4

[0075] A method for electrochemically regenerating saturated activated carbon, the main steps of which are the same as in Example 1, except that the current density is 57.14 mA / cm². 2 .

[0076] Treatment effect: Activated carbon regeneration rate was 77.85%. The phenol concentration after 5 hours of regeneration was 2.90 mg / L. According to formula (1), the phenol removal rate was 99%.

[0077] Example 5

[0078] A method for electrochemically regenerating saturated activated carbon, the main steps of which are the same as in Example 1, except that the current density is 17.14 mA / cm².2 .

[0079] Treatment effect: The activated carbon regeneration rate was 61.27%. The phenol concentration after 5 hours of regeneration was 11.23 mg / L. According to formula (1), the phenol removal rate was 95%.

[0080] Example 6

[0081] A method for electrochemical regeneration of saturated activated carbon, the main steps of which are the same as in Example 1, except that the concentration of potassium persulfate is 27 g / L.

[0082] Treatment effect: The activated carbon regeneration rate was 70.02%. The phenol concentration after 5 hours of regeneration was 4.08 mg / L. According to formula (1), the phenol removal rate was 98%.

[0083] Example 7

[0084] A method for electrochemical regeneration of saturated activated carbon, the main steps of which are the same as in Example 1, except that the concentration of potassium persulfate is 9 g / L.

[0085] Treatment effect: The activated carbon regeneration rate was 65.96%. The phenol concentration after 5 hours of regeneration was 7.4 mg / L. According to formula (1), the phenol removal rate was 97%.

[0086] Example 8

[0087] A method for electrochemical regeneration of saturated activated carbon, the main steps of which are the same as in Example 1, except that the hydrogen peroxide is added dropwise at an acceleration rate of 0.6 mL / h for the first 40 minutes and then at an acceleration rate of 0.3 mL / h for the next 260 minutes.

[0088] Treatment effect: The activated carbon regeneration rate was 71.32%. The phenol concentration after 5 hours of regeneration was 6.18 mg / L. According to formula (1), the phenol removal rate was 97%.

[0089] Comparative Example 1

[0090] A method for electrochemically regenerating saturated activated carbon, the main steps of which are the same as in Example 1, except that hydrogen peroxide solution is not added.

[0091] Treatment effect: The activated carbon fiber regeneration rate was 62.08%. The phenol concentration after 5 hours of regeneration was 9.05 mg / L. According to formula (1), the phenol removal rate was 96%. The TOC concentration in the solution after 5 hours of regeneration was 21.67 mg / L. According to formula (2), the organic matter mineralization rate was 85%.

[0092] Comparative Example 2

[0093] A method for electrochemically regenerating saturated activated carbon, the main steps of which are the same as in Example 1, except that sodium chloride is used instead of potassium persulfate and no hydrogen peroxide solution is added; the concentration of sodium chloride is 2.93 g / L.

[0094] Treatment effect: The activated carbon fiber regeneration rate was 62.54%. The phenol concentration after 5 hours of regeneration was 42.63 mg / L. According to formula (1), the phenol removal rate was 80%. The TOC concentration in the solution after 5 hours of regeneration was 137.6 mg / L. According to formula (2), the organic matter mineralization rate was 20%.

[0095] The energy consumption of Example 1 and Comparative Examples 1 and 2 was calculated using Equation (3), as shown in Table 1:

[0096]

[0097] Where P is the DC power of the energized system (W), t is the regeneration time (h), V is the regeneration liquid volume (L), C0 is the initial TOC concentration, and C t K is the TOC concentration at time t min, and K is the first-order rate constant for pollutant removal (min). -1 ).

[0098] Table 1 Energy Consumption Comparison Table

[0099]

[0100] As shown in Table 1, in the process of regenerating activated carbon, compared with the single electrolysis system and the electro-composite persulfate system, the present invention has lower energy consumption and lower cost for treating activated carbon that adsorbs the same amount of organic matter.

[0101] In addition, such as Figure 6 As shown, in the electrocoupled persulfate and hydrogen peroxide system of this invention, SO · 4 - The yield is 18.2 times that of the electrocoupled persulfate system in Comparative Example 1. The more active oxygen there is, the stronger the ability to degrade and mineralize organic matter. Therefore, this invention can maximize the degradation and mineralization of organic matter while reducing the amount of pharmaceutical input and saving costs.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the technical solutions. Those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of the present invention without departing from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A method for electrochemically regenerating activated carbon, characterized in that, Saturated activated carbon containing adsorbed organic matter is placed in an anode-cathode system containing a regeneration solution, with the cathode positioned thereon. Two peroxides, peroxide I and peroxide II, are added to the regeneration solution. Peroxide I is a persulfate. The power is then turned on to initiate the reaction, and peroxide II is continuously added dropwise during the reaction. After the reaction is complete, the activated carbon is removed and dried to obtain regenerated activated carbon. The regeneration solution is water or an aqueous solution containing electrolytes.

2. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, The operating current density of the electrode system is 10~120 mA / cm². 2 .

3. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, The mass ratio of activated carbon, persulfate, and peroxide II is 1:5~50:5~50.

4. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, The peroxide II is hydrogen peroxide.

5. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, The organic compound is one or more of the following: halogenated organic compounds, phenol, antibiotics, and endocrine disruptors.

6. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, During the reaction, peroxide II is continuously added in stages and at different rates.

7. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, In the electrode system, the cathode is a metal electrode or a metal composite electrode, which serves as a support layer for placing the activated carbon to be regenerated; the anode is a metal electrode, a metal oxide electrode, a graphite electrode, or a metal composite electrode.

8. The method for electrochemically regenerating activated carbon according to claim 1, characterized in that, The activated carbon is powdered activated carbon, granular activated carbon, activated carbon fiber, or carbon felt.

9. The method for electrochemically regenerating activated carbon according to claim 3, characterized in that, The mass ratio of activated carbon, persulfate, and peroxide II is 1:10~40:10~45.

10. The method for electrochemically regenerating activated carbon according to claim 6, characterized in that, The dropping rate of the peroxide II in the first 0.5-1 hours is greater than the dropping rate during the remaining reaction time.

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