A method for degrading chlorophenol organic pollutants in water by activating persulfate with a cobalt-cerium dioxide monatomic catalyst in the presence of bicarbonate

Abstract

The present application belongs to the field of water pollution treatment, and particularly relates to a method for degrading chlorophenol organic pollutants in water by activating persulfate with a cobalt-cerium dioxide monatomic catalyst in the presence of bicarbonate. The present application calcines cerium nitrate hexahydrate in a muffle furnace to obtain cerium dioxide. A catalyst precursor is prepared by using a traditional equal-volume impregnation method. The catalyst precursor is annealed at different temperatures to obtain a series of catalysts, wherein Co1-CeO2-700 has the best catalytic performance and has more excellent catalytic performance in the presence of bicarbonate. The preparation method provided by the present application has simple steps, is easy to operate, has fast effect on treating chlorophenol, high product yield, low cost, good economic value and social benefits. The monatomic catalyst prepared by the present application has high atomic utilization rate, good stability and excellent catalytic effect, and is expected to become a key technology for solving actual water environmental organic pollution.

Description

Technical Field

[0001] This invention belongs to the field of water pollution treatment, specifically relating to a method and application of activating PMS with a cobalt-cerium dioxide single-atom catalyst to degrade chlorophenols in water in the presence of a certain amount of bicarbonate ions. Background Technology

[0002] Chlorophenols (CPs) are a class of highly stable and recalcitrant organic pollutants, widely found in industrial wastewater (such as oil refining, coking, papermaking, and textiles) and domestic sewage. Due to their broad-spectrum bactericidal properties, CPs are often used as raw materials in the pesticide, pharmaceutical, and textile printing and dyeing industries, and are applied to the disinfection and preservation of wooden furniture, fruits and vegetables, leather, and coatings. Therefore, as typical organic halogenated pollutants in the environment, CPs are often found in incompletely treated industrial wastewater. Their poor biodegradability and long-term accumulation in organisms lead to teratogenic, carcinogenic, and mutagenic effects. Furthermore, CPs are environmentally persistent, recognized as toxic and hazardous pollutants, and have been listed as priority pollutants by many countries. Among monochlorophenols, p-chlorophenol (4-CP) is the most toxic; wastewater containing 4-CP must be treated before being discharged into the environment. Controlling environmental pollution caused by 4-CP is of great significance for ensuring the health of people and various organisms in the environment. However, due to the high stability and difficulty in degradation of 4-CP, conventional treatment methods such as biological, physical, and some chemical methods cannot completely and cost-effectively remove 4-CP.

[0003] To address this issue, advanced oxidation technologies (AORs) utilize methods such as Fenton reactions, Fenton-like reactions, ozone, hydrogen peroxide, photolysis, photocatalysis, sonication, and electrochemistry to generate highly reactive species with strong oxidizing capabilities, thereby achieving effective wastewater treatment. These technologies are characterized by high efficiency, wide applicability, and thorough degradation. Due to the unique asymmetric structure of PMS, it is easily activated to generate large amounts of reactive oxygen species (ROS) for the elimination of 4-CP. Persulfate-based AOR processes have been accepted as one of the preferred methods. They primarily oxidize and degrade organic pollutants by activating oxidants (such as hydrogen peroxide and PMS) with catalysts to generate reactive oxygen species. Summary of the Invention

[0004] The purpose of this invention is to provide a solution with a certain amount of bicarbonate (HCO3) - This invention discloses a method and application for degrading chlorophenol organic pollutants in water by activating persulfate (PMS) with a cobalt-cerium dioxide single-atom catalyst (Co1-CeO2). The catalyst prepared by this invention has the characteristics of high atom utilization and can efficiently degrade chlorophenol organic pollutants, achieving rapid degradation of chlorophenol organic pollutants within 10 minutes.

[0005] To achieve the above objectives, the present invention provides the following technical solution: cerium dioxide and cobalt nitrate hexahydrate are impregnated in water, dried, and the dried solid is collected and calcined at different temperatures to obtain a cobalt-cerium dioxide single-atom catalyst. The cobalt-cerium dioxide single-atom catalyst and PMS are added to the polluted water body to oxidize and remove aromatic organic pollutants in the water body.

[0006] Using a cobalt-cerium dioxide single-atom catalyst in conjunction with a potassium persulfate PMS system, in the presence of HCO3 - The oxidative degradation of chlorophenol in polluted water includes the following steps:

[0007] (1) The support cerium dioxide and cobalt nitrate hexahydrate were impregnated in water, dried, and the dried solid was collected and calcined at different temperatures to obtain cobalt-cerium dioxide single-atom catalysts. The catalysts were annealed in air at 500℃-700℃ with a heating rate of 5℃ / min for 10.0h.

[0008] (2) Add cobalt-cerium dioxide single-atom catalyst and potassium persulfate PMS to HCO3 containing bicarbonate ions. - The polluted water body has a bicarbonate concentration of 0.1 mM to 1 mM, and chlorophenols in the water body are oxidized and eliminated.

[0009] Preferably, the calcination temperature in step (1) is 700℃.

[0010] Preferably, the mass ratio of the support cerium dioxide to cobalt is 1:0.02; the mass concentration and molar concentration of the cobalt-cerium dioxide single-atom catalyst and PMS are 0.15-0.2 g / L and 0.2-0.6 mM, respectively.

[0011] Preferably, the specific preparation methods for the cobalt-cerium dioxide single-atom catalysts Co1-CeO2-500 and Co1-CeO2-700 are as follows:

[0012] (1) 4g of Ce(NO3)3·6H2O was placed in a muffle furnace, heated at a rate of 5℃ / min, and calcined at 350℃ for 2.0h to obtain CeO2, which was then ground.

[0013] (2) The Co1-CeO2 catalyst precursor was prepared by the traditional equal volume impregnation method. The CeO2 obtained in step (1) was slurried in deionized water under stirring, and the required amount of Co(NO3)2 solution was added dropwise. The mixture was impregnated for 2.0 h, dried under vacuum at 40 °C overnight, and a Co-CeO2 catalyst precursor with a Co loading of 2.0 wt% was prepared.

[0014] (3) The Co1-CeO2 catalyst precursor obtained in step (2) is ground and annealed for 10.0 h in an air atmosphere at 500℃ and 700℃ respectively, with a heating rate of 5℃ / min. The resulting catalysts are denoted as Co1-CeO2-500 and Co1-CeO2-700 respectively.

[0015] Preferably, the cobalt-cerium dioxide single-atom catalyst has an atomic dispersion effect, which can achieve rapid degradation and removal of chlorophenol within 10 minutes.

[0016] Preferably, a cobalt-cerium dioxide single-atom catalyst is added to water containing chlorophenol, thoroughly mixed and stirred, and then PMS is added. The oxidant is activated by the cobalt-cerium dioxide single-atom catalyst, generating a large number of free radicals and non-free radicals, which then decompose HCO3-. - Converted to CO3 ·- It can efficiently degrade chlorophenol.

[0017] Preferably, in 1mM HCO3 - Under the given conditions, Co-CeO2-700 / HCO3 - The PMS system can completely degrade 5 mg / L of 4-CP within 10 minutes.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] (1) This invention proposes that in water containing 1 mM bicarbonate, this catalyst can efficiently activate 0.2 mM PMS and completely degrade 5 mg / L of p-chlorophenol (4-CP) within 10 minutes. Experiments show that Co-CeO2-700 / HCO3 - The / PMS system generates SO4. ·- O2 ·- , 1 O2 and CO3 ·- It contains multiple reactive oxygen species, including CO3. Compared to the Co-CeO2-700 / PMS system, it adds CO3. ·- The generation of HCO3 significantly enhances the degradation effect. Current research rarely considers the ubiquitous presence of HCO3 at environmentally relevant concentrations. - To mitigate the potential impacts of HCO3, this invention proposes the study of HCO3, which is prevalent in real-world water bodies. - It can efficiently degrade 4-CP and is suitable for the treatment of organic pollutants in industrial wastewater.

[0020] (2) The degradation rate is greatly improved: at 1mM HCO3 - Under the given conditions, the Co-CeO2-700 / HCO3 of the present invention -The PMS system can completely degrade 5 mg / L of 4-CP within 10 minutes, while traditional heterogeneous catalysts (such as Fe3O4, MnO2, CuO / Al2O3, TiO2, ZnO, zero-valent iron, montmorillonite, hematite, etc.) typically require more than 60 minutes to achieve the same effect, demonstrating a significant advantage. This system not only requires a smaller catalyst dosage (only 0.2 g / L, far lower than the 0.5–1 g / L of traditional catalysts) but also exhibits a faster degradation rate, providing a superior solution for environmental remediation.

[0021] (3) Environmental adaptability breakthrough HCO3 - Inhibition effect: In traditional advanced oxidation technologies, HCO3 - Typically considered a free radical scavenger, HCO3 can reduce degradation efficiency. However, this invention innovatively utilizes HCO3... - Converted to CO3 ·- (E 0 =1.78V), which changes it from an "inhibitor" to an "accelerator".

[0022] (4) Reduced catalyst cost: The cobalt-cerium dioxide single-atom catalyst developed in this invention has a metal loading of only 2wt%, compared with traditional nanocatalysts (such as supported Co3O4, Fe2O3 nanoparticles, Ni / Al2O3, CuO-TiO2 composite materials, etc.) which usually require 10-20wt% metal loading. The amount of metal used is reduced to 1 / 5-1 / 10, which greatly reduces the amount of metal used and significantly reduces the catalyst cost.

[0023] (5) Clarify Co-CeO2-700 / HCO3 - The synergistic mechanism of the / PMS ternary system was confirmed by probe experiments for CO3. ·- Its key role provides new ideas for designing environmentally friendly catalysts.

[0024] These advantages make the present invention highly competitive in engineering applications, and it is particularly suitable for the deep treatment of recalcitrant organic wastewater from industries such as papermaking and dyeing.

[0025] (6) Figure 5 As shown, the Co1-CeO2-700 single-atom catalyst prepared in this experiment exhibits excellent catalytic performance in the degradation of 4-CP. In the Co1-CeO2-700 / PMS system, the removal rate of 4-CP is 40% after 20 min; while in the Co1-CeO2-700 / HCO3 system... - In the PMS system, complete degradation of 4-CP (100% removal rate) can be achieved in 10 minutes. This result indicates that HCO3- - The introduction of [the substance] significantly improves the activation efficiency of PMS, and may achieve efficient degradation by promoting the free radical generation oxidation pathway. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is the XRD pattern of the single-atom catalyst prepared in Example 1 of the present invention;

[0028] Figure 2 This is an EPR diagram of the oxygen vacancies in Co1-CeO2-700 prepared in Example 1 of this invention;

[0029] Figure 3 The graph shows the effect of a series of catalysts prepared in Case 1 on the activation of PMS for the degradation of p-chlorophenol (4-CP);

[0030] Figure 4 This is a graph showing the effect of Co1-CeO2-700 prepared in Case 1 on the adsorption of p-chlorophenol (4-CP);

[0031] Figure 5 The best single-atom catalyst prepared in Implementation Case 1 is used in quantitative HCO3 - The effect of activated PMS on the degradation of p-chlorophenol (4-CP) in the presence of the present element is illustrated in the figure.

[0032] Figure 6 This is a graph showing the effect of quenching experiments on Co1-CeO2-700 prepared in Example 1 of this invention to determine the active species;

[0033] Figure 7 The Co1-CeO2-700 prepared in Example 1 of this invention is a product with a certain amount of HCO3 - The effect of quenching experiments in the presence of active species is shown in the diagram.

[0034] Figure 8 The Co1-CeO2-700 prepared in Example 1 of this invention is a product with a certain amount of HCO3 - The effect of probe experiments in the presence of activated PMS. Detailed Implementation

[0035] The following examples further illustrate the above-described content of the present invention, but it should not be construed as limiting the scope of the subject matter of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention.

[0036] Example 1:

[0037] Preparation of Co1-CeO2 single-atom catalyst:

[0038] 4 g of Ce(NO3)3·6H2O was placed in a muffle furnace and calcined at 350 °C for 2.0 h at a heating rate of 5 °C / min to obtain CeO2. A Co1-CeO2 catalyst precursor was prepared using a conventional equal-volume impregnation method. 2 g of the obtained CeO2 was added to a small amount of deionized water and stirred to form a slurry. 2 mL of 0.34 M Co(NO3)2 solution was added dropwise, and the mixture was impregnated for 2.0 h. The mixture was then vacuum dried at 40 °C overnight. A Co1-CeO2 catalyst precursor with a Co loading of 2.0 wt% was prepared.

[0039] The obtained Co1-CeO2 catalyst precursor was dried overnight, then ground and annealed in air at 300℃, 500℃, 700℃, and 800℃ for 10.0 h at a heating rate of 5℃ / min. The resulting catalysts were named Co1-CeO2-300, Co1-CeO2-500, Co1-CeO2-700, and Co1-CeO2-800, respectively.

[0040] The single-atom catalyst prepared in Example 1 was subjected to phase analysis by XRD. Figure 1 As shown, the diffraction peaks of 2θ in the single-atom catalyst at 28.55°, 33.08°, 47.48°, 56.34°, 59.09°, 69.42°, 76.70°, and 79.07° correspond to the (111), (200), (220), (311), (222), (400), (331), (420), and (422) planes of the standard card of CeO2 with the number No.00-043-1002, respectively. This confirms the formation of the Co1-CeO2 single-atom catalyst. Figure 1 The characteristic peaks of the standard card are provided below. For example... Figure 2 As shown, a distinct oxygen vacancy characteristic signal was measured in the obtained optimal material (Co1-CeO2-700). Oxygen vacancies (Vo) in cerium dioxide (CeO2) can be clearly characterized by electron paramagnetic resonance (EPR), with characteristic signals typically appearing in the range of g≈1.96–2.01, corresponding to the paramagnetic CeO2 formed by oxygen vacancy trapping electrons. 3+ -Vo Defect Center.

[0041] Example 2:

[0042] Optimal material selection:

[0043] Typically, the catalytic degradation experiment is conducted in a 50mL vial, with magnetic stirring at 750 rpm throughout the experiment, and the water bath temperature maintained at 25℃. The specific steps are as follows:

[0044] Add 30 mL of 5 mg / L 4-CP solution to a vial. Under magnetic stirring, add PMS stock solution sequentially to achieve a concentration of 0.6 mM in the reaction system (selecting a relatively high concentration of 0.6 mM is crucial for efficient screening of the optimal material). Add a single-atom material suspension to achieve a concentration of 0.2 g / L in the reaction system to initiate the reaction. At a specified time point, take 1 mL of the reaction solution and quickly mix it with 1 mL of 10 mM sodium thiosulfate aqueous solution to terminate the reaction. Filter the mixture through a 0.22 μm polytetrafluoroethylene filter into a brown liquid chromatography vial. Detect residual contaminants using high-performance liquid chromatography (HPLC). All degradation experiments were performed in triplicate, and the results are expressed as mean and standard deviation.

[0045] In addition, the material was added separately to a 4-CP solution to evaluate the adsorption performance of the single-atom material for 4-CP, such as... Figure 4 As shown, the adsorption effect of the material itself is not significant. All degradation experiments were performed in triplicate, and the results are expressed as mean and standard deviation.

[0046] The results are as follows Figure 3 As shown, the Co1-CeO2 single-atom catalyst prepared in this experiment exhibited excellent catalytic performance in the degradation of 4-CP. Under the conditions of PMS concentration of 0.6 mM, material concentration of 0.2 g / L, and 4-CP concentration of 5 mg / L, the removal rates of 4-CP, ranked from highest to lowest, were: Co1-CeO2-700 > Co1-CeO2-500 > Co1-CeO2-300 > Co-CeO2-800. Among them, Co1-CeO2-700 showed the best catalytic performance, degrading all 5 mg / L of 4-CP in 30 min. This was followed by Co1-CeO2-500 with a 92% degradation rate in 30 min; Co1-CeO2-300 with a 78% degradation rate in 30 min; and Co-CeO2-800 with a 59% degradation rate in 30 min.

[0047] Example 3:

[0048] Co1-CeO2-700 / PMS and Co1-CeO2-700 / HCO3 - Degradation effect of PMS system determined:

[0049] The catalytic degradation experiment was conducted in 50mL vials, with magnetic stirring at 750rpm throughout the experiment, and the water bath temperature maintained at 25℃. The specific steps are as follows:

[0050] Add 30 mL of 5 mg / L 4-CP solution to a vial. Under magnetic stirring, add PMS stock solution sequentially to achieve a concentration of 0.2 mM in the reaction system (this concentration of 0.2 mM is chosen to generate sufficient free radicals, ensuring complete degradation of pollutants while achieving optimal reagent utilization and treatment economy); add single-atom material suspension to a concentration of 0.2 g / L in the reaction system, and Co1-CeO2-700 / HCO3. - Adding NaHCO3 mother liquor to the PMS system reduces the HCO3 content in the system. - The reaction was initiated with a concentration of 1 mM; at specified time points, 1 mL of the reaction solution was taken and rapidly mixed with 1 mL of 10 mM sodium thiosulfate aqueous solution to terminate the reaction; the mixture was filtered through a 0.22 μm polytetrafluoroethylene filter into a brown liquid chromatography vial, and residual contaminants were detected by high performance liquid chromatography (HPLC). All degradation experiments were performed in triplicate, and the results are expressed as mean and standard deviation.

[0051] The results are as follows Figure 5 As shown, the Co1-CeO2-700 single-atom catalyst prepared in this experiment exhibits excellent catalytic performance in the degradation of 4-CP. In the Co1-CeO2-700 / PMS system, the removal rate of 4-CP is 40% after 20 min; while in the Co1-CeO2-700 / HCO3 system... - In the PMS system, complete degradation of 4-CP (100% removal rate) can be achieved in 10 minutes. This result indicates that HCO3- - The introduction of [the substance] significantly improves the activation efficiency of PMS, and may achieve efficient degradation by promoting the free radical generation oxidation pathway.

[0052] Example 4:

[0053] Co-CeO2-700 / PMS system and Co-CeO2-700 / HCO3 - Identification of active species generated during the degradation process of the PMS system:

[0054] Typically, the catalytic degradation experiment is conducted in a 50mL vial, with magnetic stirring at 750 rpm throughout the experiment, and the water bath temperature maintained at 25℃. The specific steps are as follows:

[0055] Add 30 mL of 5 mg / L 4-CP solution to a vial. Under magnetic stirring, add PMS stock solution sequentially to a concentration of 0.6 mM in the reaction system; single-atom material suspension to a concentration of 0.2 g / L in the reaction system; and the corresponding active species quencher to initiate the reaction. At a specified time point, take 1 mL of the reaction solution and quickly mix it with 1 mL of 10 mM sodium thiosulfate aqueous solution to terminate the reaction. Filter the above mixture through a 0.22 μm polytetrafluoroethylene filter membrane into a brown liquid chromatography vial, and detect residual contaminants using high performance liquid chromatography (HPLC).

[0056] To analyze the main active species in the degradation of 4-CP by the Co1-CeO2-700 / PMS system, methanol (MeOH), tert-butanol (TBA), 2,2,6,6-tetramethylpiperidin-1-oxy (TEMPO), furfuryl alcohol (FFA), and 1,10-phenanthroline (phen) were selected as quenchers for active species quenching experiments to elucidate the role of free radicals (SO42-). ·- , · OH, O2 ·- ) and non-free radicals ( 1 The role of O2 in the degradation process.

[0057] All degradation experiments were performed in triplicate, and the results are expressed as mean and standard deviation. The quenching experiment results are as follows: Figure 6 As shown, after adding phen (5 mM) to the system, the degradation rate of 4-CP within 20 min was less than 5%. This is because phen's strong metal chelating ability blocks the reaction between the single-atom Co site and PMS, thereby inhibiting the degradation of 4-CP. Adding MeOH (20 mM) to the system as SO42-... ·- and · OH quencher, the degradation rate of 4-CP within 20 min was only 20%; TBA was added to the system as... · The fact that the removal rate of 4-CP hardly decreased when using OH quenchers indicates that the system contains SO4. ·- ,and · OH is not the main active species leading to 4-CP degradation. When TEMPO (5 mM) is added to this system, O2 is quenched. ·- At that time, the degradation efficiency of 4-CP decreased from 40% to 10%, indicating that the system contained O2. ·- When FFA (5mM) is added to this system for quenching... 1 When O2 is present, the degradation efficiency of 4-CP decreases from 40% to 2%, indicating that the system contains [O2]. 1 O2.

[0058] To analyze Co1-CeO2-700 / HCO3 -The main active species in the degradation of 4-CP by the PMS system were analyzed using methanol (MeOH), tert-butanol (TBA), 2,2,6,6-tetramethylpiperidin-1-oxy (TEMPO), furfuryl alcohol (FFA), and 1,10-phenanthroline (phen) as quenchers to elucidate the quenching of active species during the degradation process. ·- , · OH, O2 ·- ) and non-free radicals ( 1 The role of O2 in the degradation process.

[0059] All degradation experiments were performed in triplicate, and the results are expressed as mean and standard deviation. The quenching experiment results are as follows: Figure 7 As shown, after adding phen (5 mM) to the system, the degradation rate of 4-CP within 20 min was less than 5%. This is because phen's strong metal chelating ability blocks the reaction between the single-atom Co site and PMS, thereby inhibiting the degradation of 4-CP. Adding MeOH (20 mM) to the system as SO42-... ·- and · OH quencher, the degradation rate of 4-CP within 20 minutes was only 50%; TBA was added to the system as... · The fact that the removal rate of 4-CP hardly decreased when using OH quenchers indicates that the system contains SO4. ·- ,and · OH is not the main active species leading to 4-CP degradation. When TEMPO (5 mM) is added to this system, O2 is quenched. ·- At that time, the degradation efficiency of 4-CP decreased from 100% to 40%, indicating that the system contained O2. ·- When FFA (5mM) is added to this system for quenching... 1 When O2 is present, the degradation efficiency of 4-CP decreases from 100% to 3%, indicating that the system contains [a substance that is not present in the system]. 1 O2.

[0060] Therefore, it can be concluded that both systems contain SO4. ·- O2 ·- and 1 O2.

[0061] Example 5:

[0062] Co1-CeO2-700 / HCO3 - / PMS system probe experiment:

[0063] N,N-Dimethylaniline (DMA) is known for its affinity for CO3. ·- Its high selectivity and reactivity make it suitable as a molecular probe for quantifying CO3. ·- concentration.

[0064] Co1-CeO2-700 / HCO3 - The / PMS probe experiment was conducted in a 50mL vial. Magnetic stirring at 750 rpm was used throughout the experiment, and the water bath temperature was maintained at 25℃. The specific steps are as follows:

[0065] Add 30 mL of 10 μM DMA solution to a vial. Under magnetic stirring, add NaHCO3 solution, PMS stock solution and single-atom material suspension in sequence to start the reaction. Take 1 mL of the reaction solution at a specified time point and quickly mix it with 1 mL of sodium thiosulfate aqueous solution to terminate the reaction. Filter the above mixture through a 0.22 μm polytetrafluoroethylene filter membrane into a brown liquid chromatography vial. Analyze the concentration decay of DMA using high performance liquid chromatography (HPLC).

[0066] The results are as follows Figure 8 As shown, the concentration of DMA dropped to 0 within 5 minutes, indicating that CO3... ·- The generation of.

[0067] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, not all embodiments. Other embodiments can be obtained without inventiveness based on these embodiments, and all equivalent changes and modifications made in accordance with the scope of the claims of the present invention should be protected within the scope of the present invention.

Claims

1. A method for degrading chlorophenol organic pollutants in water using a cobalt-cerium dioxide single-atom catalyst activated in the presence of bicarbonate, characterized in that, Using a cobalt-cerium dioxide single-atom catalyst in conjunction with a potassium persulfate PMS system, in the presence of HCO3 - The oxidative degradation of chlorophenol in polluted water includes the following steps: (1) The support cerium dioxide and cobalt nitrate hexahydrate were impregnated in water, dried, and the dried solid was collected and calcined at different temperatures to obtain cobalt-cerium dioxide single-atom catalysts. The catalysts were annealed in air at 500℃-700℃ with a heating rate of 5℃ / min for 10.0h. (2) Add cobalt-cerium dioxide single-atom catalyst and potassium persulfate PMS to HCO3 containing bicarbonate ions. - The polluted water body has a bicarbonate concentration of 0.1 mM to 1 mM, and chlorophenols in the water body are oxidized and eliminated.

2. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 1, characterized in that, The calcination temperature in step (1) is 700℃.

3. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 1, characterized in that, The mass ratio of the support cerium dioxide to cobalt is 1:0.02; the mass concentration and molar concentration of the cobalt-cerium dioxide single-atom catalyst and PMS are 0.15-0.2 g / L and 0.2-0.6 mM, respectively.

4. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 1, characterized in that, The specific preparation methods for cobalt-cerium dioxide single-atom catalysts Co1-CeO2-500 and Co1-CeO2-700 are as follows: (1) 4g of Ce(NO3)3·6H2O was placed in a muffle furnace, heated at a rate of 5℃ / min, and calcined at 350℃ for 2.0h to obtain CeO2, which was then ground. (2) The Co1-CeO2 catalyst precursor was prepared by the traditional equal volume impregnation method. The CeO2 obtained in step (1) was slurried in deionized water under stirring, and the required amount of Co(NO3)2 solution was added dropwise. The mixture was impregnated for 2.0 h, dried under vacuum at 40 °C overnight, and a Co-CeO2 catalyst precursor with a Co loading of 2.0 wt% was prepared. (3) Grind the Co1-CeO2 catalyst precursor obtained in step (2) and heat it at 500℃ and 700℃ respectively. o In an air atmosphere, the heating rate was 5℃ / min, and the annealing time was 10.0h. The resulting catalysts were denoted as Co1-CeO2-500 and Co1-CeO2-700, respectively.

5. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 1, characterized in that, The cobalt-cerium dioxide single-atom catalyst has an atomic dispersion effect, which can achieve rapid degradation and removal of chlorophenol within 10 minutes.

6. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 1, characterized in that, A cobalt-cerium dioxide single-atom catalyst was added to water containing chlorophenol, thoroughly mixed and stirred, and then PMS was added. The oxidant was activated by the cobalt-cerium dioxide single-atom catalyst, generating a large number of free radicals and non-free radicals, which then converted HCO3- into HCO3-. - Converted to CO3 ·- It can efficiently degrade chlorophenol.

7. The method for degrading chlorophenol organic pollutants in water by activating a cobalt-cerium dioxide single-atom catalyst in the presence of bicarbonate according to claim 4, characterized in that, In 1mM HCO3 - Under the given conditions, Co-CeO2-700 / HCO3 - The PMS system can completely degrade 5 mg / L of 4-CP within 10 minutes.

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