Preparation method and application method of a multi-level pore nitrogen-doped carbon loaded iron oxide cluster and iron single-atom catalyst

Abstract

The application discloses a preparation method and application method of a multi-level hole nitrogen-doped carbon loaded iron oxide cluster and iron single-atom catalyst, and comprises the following steps: S1, preparing an iron-based metal organic framework; calcining the iron-based metal organic framework under a nitrogen or argon atmosphere at high temperature to obtain a carbonized iron-based metal organic framework; S2, adding 50 mg of the carbonized iron-based metal organic framework into 100 mL of an acid solution, and magnetically stirring at room temperature; and removing unstable iron species through acid washing; S3, repeatedly leaching the carbonized iron-based metal organic framework after the acid washing with distilled water, and drying the carbonized iron-based metal organic framework in a vacuum drying box after washing to neutrality; and S4, grinding the powder obtained in the step S3 with a jade mortar to obtain the multi-level hole nitrogen-doped carbon loaded iron oxide cluster and iron single-atom catalyst. The application can effectively increase channels for reaction substrates to reach active sites, improve utilization of the active sites, and strengthen the performance of traditional iron single-atom catalysts, and can be used for catalytic activation of persulfate.

Description

Technical Field

[0001] This invention relates to the field of catalyst materials technology, specifically to a method for preparing and applying a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst. Background Technology

[0002] Persulfate advanced oxidation technology has shown great potential in the removal of persistent pollutants in aquatic environments. Generally, the direct oxidation effect of persulfate on organic pollutants is very limited. Catalytic activation has attracted widespread attention because it can activate persulfate to generate more active species, thereby enhancing its oxidation capacity. The key lies in the design and synthesis of highly efficient catalytic activators.

[0003] Iron-nitrogen-carbon (Fe-NC) materials are a type of heterogeneous catalytic material that has attracted much attention from researchers in recent years, and have been widely used in advanced persulfate oxidation technology due to their green and efficient advantages. Generally, the catalytic reaction only occurs on the surface of particulate catalysts, with almost no reaction occurring inside the particles. Therefore, for Fe-NC catalysts with high iron loading, only a small number of metal active components actually participate in the catalytic reaction, and a large number of metal active sites remain unutilized. Iron single-atom-nitrogen-carbon catalysts (Fe SACs-NC) are a special type of Fe-NC catalyst where the iron components on the support exist in a single-atom dispersed form. Compared with traditional Fe-NC catalysts, the atom utilization rate is significantly improved, and the metal active sites are fully exposed, thus exhibiting stronger catalytic activity.

[0004] However, previous studies have reported that the symmetrical electronic structure of the Fe-N4 configuration in Fe SACs-NC is unfavorable for optimal adsorption of oxygen intermediates, thus limiting the number of active species generated during catalysis. Furthermore, due to its simple structure and lack of synergistic active sites, Fe SACs-NC exhibits inherent performance limitations in complex catalytic reactions. Therefore, in current research, introducing adjacent active sites to obtain more efficient and stable single-atom catalysts by rationally adjusting the electronic structure of Fe-N4 and the synergistic effects between active sites remains a significant challenge. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst. This method introduces iron oxide clusters adjacent to Fe-N4, which can consume the electron density around the iron single-atom sites, giving the catalyst a higher oxidation state, and further enhancing the catalytic ability through the synergistic effect of the clusters and single atoms. Furthermore, the catalyst obtained by this method has microporous, mesoporous, and macroporous structures. The hierarchical pore structure not only enhances the catalyst stability but also provides more channels for reactants to reach the active site center. The significant improvement in active site utilization promotes substrate transport and catalytic reaction, and can be used for persulfate catalytic activation to achieve efficient removal of pollutants.

[0006] This invention is achieved through the following technical solution: a method for preparing hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts, comprising the following steps:

[0007] S1. Preparation of iron-based metal-organic frameworks: The iron-based metal-organic frameworks are calcined at high temperature under a nitrogen or argon atmosphere to obtain iron-carbide metal-organic frameworks.

[0008] S2. Add 50 mg of iron carbide-based metal-organic framework to 100 mL of acid solution, stir magnetically at room temperature for a certain period of time, and acid wash to remove unstable iron species.

[0009] S3. The acid-washed iron carbide-based metal-organic framework is repeatedly rinsed with distilled water until neutral and then dried in a vacuum drying oven.

[0010] S4. The powder obtained in step S3 is ground with an agate mortar to obtain hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts.

[0011] Further: The carbon-based metal-organic framework mentioned in step S1 is any one of MIL-53, MIL-88B, MIL-100 and MIL-101.

[0012] Further: The preparation method of the iron-based metal-organic framework MIL-53 is as follows: accurately weigh 1.34 g of Fe(NO3)3·9H2O into a 100 mL polytetrafluoroethylene reactor, add 56 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.83 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 150 °C at a rate of 5 °C / min and maintain it for 15 h. After cooling to room temperature, wash three times with N,N-dimethylformamide and methanol by centrifugation, dry in a vacuum drying oven at 80 °C for 12 h, and grind with an agate mortar to obtain MIL-53(Fe) solid powder;

[0013] The preparation method of the iron-based metal-organic framework MIL-88B is as follows: accurately weigh 0.3108 g of FeCl3·6H2O into a 100 mL polytetrafluoroethylene reactor, add 25 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.1911 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform, and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 150 °C at a rate of 5 °C / min and maintain it for 12 h. After cooling to room temperature, wash three times with N,N-dimethylformamide and methanol by centrifugation, dry in an 80 °C vacuum drying oven for 12 h, and grind with an agate mortar to obtain MIL-88B(Fe) solid powder.

[0014] Further: The preparation method of the iron-based metal-organic framework MIL-100 is as follows: accurately weigh 0.8104 g of Fe(NO3)3·9H2O into a 100 mL polytetrafluoroethylene reactor, add 30 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.4983 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 150 °C at a rate of 5 °C / min and maintain it for 10 h. After cooling to room temperature, wash three times with N,N-dimethylformamide and methanol by centrifugation, dry in a vacuum drying oven at 80 °C for 12 h, and grind with an agate mortar to obtain MIL-100(Fe) solid powder;

[0015] The preparation method of the iron-based metal-organic framework MIL-101 is as follows: accurately weigh 1.35 g of FeCl3·6H2O into a 100 mL polytetrafluoroethylene reactor, add 30 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.415 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 110 °C at a rate of 5 °C / min and maintain it for 24 h. After cooling to room temperature, wash three times with ethanol and deionized water respectively, dry in a vacuum drying oven at 100 °C for 12 h, and grind with an agate mortar to obtain MIL-101(Fe) solid powder.

[0016] Further: the high-temperature calcination temperature in step S1 is 700-750℃, and the high-temperature calcination time is 1.5-2h.

[0017] Further: the acid solution mentioned in step S2 is any one of hydrochloric acid, sulfuric acid, and nitric acid, with a concentration of 1-5 mol / L, and the magnetic stirring time is 8-24 h.

[0018] Further: The vacuum drying temperature in step S3 is 60-100℃, and the drying time is 6-24h.

[0019] Furthermore: the hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalyst described in step S4 have a hierarchical porous structure containing micropores, mesopores and macropores, and the iron loading is 0.4-0.6%. The iron is uniformly dispersed on the support in the form of single atoms and iron oxide clusters. The N source that forms Fe-N coordination bonds with the iron is the organic solvent N,N-dimethylformamide used in the solvothermal preparation of iron-based metal-organic frameworks.

[0020] A method for applying hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts is disclosed, which utilizes hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts to activate persulfate to degrade phenolic pollutants in the aquatic environment.

[0021] Furthermore, the dosage of the hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalyst is 0.05-0.2 g / L, and the dosage of persulfate is 0.025-0.2 g / L. The persulfate is any one or more of persulfate monosulfate and perdisulfate, and the phenolic pollutants are bisphenol A, bisphenol S, bisphenol F, and bisphenol fluorene. The time required for complete degradation of the pollutants is 5-30 min.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. In this invention, the iron single-atom site Fe-N x The nitrogen source required for formation is N,N-dimethylformamide, the solvent used in the solvothermal preparation of metal-organic frameworks. No additional nitrogen source needs to be added during the single-atom synthesis process.

[0024] 2. The synergistic effect between iron oxide clusters and iron single atoms can improve the oxidation state of the catalyst, promote the adsorption of oxygen intermediates and the formation of active species during the catalytic process, and significantly improve the catalytic efficiency.

[0025] 3. The catalyst of the present invention has multiple pore structures, including micropores, mesopores, and macropores. This structure has the following advantages: (1) it increases the number of active sites and improves catalytic efficiency; (2) it helps to improve species diffusion efficiency and accelerate reaction rate; (3) it helps to shorten electron diffusion paths and improve electron transfer efficiency; and (4) it helps to enhance the structural stability of the catalyst. Attached Figure Description

[0026] Figure 1 The X-ray diffraction (XRD) pattern of the catalyst in Example 1 of this invention;

[0027] Figure 2 The image shows the aberration-corrected high-angle annular dark-field scanning electron microscope (AC-HAADFSTEM) pattern of the catalyst in Example 1 of this invention.

[0028] Figure 3 The specific surface area analysis results are for the catalyst in Example 1 of this invention;

[0029] Figure 4 AC-HAADFSTEM image of the catalyst in Example 2 of this invention;

[0030] Figure 5 The results of synchrotron radiation (XAFS) analysis of the catalyst in Example 2 of this invention are shown below.

[0031] Figure 6 The specific surface area analysis results are for the catalyst in Example 2 of this invention;

[0032] Figure 7 This is an AC-HAADFSTEM image of the catalyst in Example 3 of the present invention;

[0033] Figure 8 This is an AC-HAADFSTEM image of the catalyst in Example 4 of the present invention;

[0034] Figure 9 AC-HAADFSTEM image of the catalyst in Example 5 of this invention;

[0035] Figure 10 This is a diagram showing the degradation effect of the catalyst in Example 1 of the present invention on phenolic pollutants;

[0036] Figure 11 The figures show the degradation effect of the catalysts in Examples 1-5 of this invention on bisphenol A. Detailed Implementation

[0037] The present invention will be described in detail below with reference to specific embodiments:

[0038] Preparation of hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts

[0039] Example 1

[0040] Using MIL-88B(Fe) as a precursor, the temperature was raised to 700℃ at a rate of 5℃ / min under a nitrogen atmosphere and held for 2 h, then cooled to room temperature. 50 mg of the prepared black carbonized MIL-88B(Fe) powder was placed in 100 mL of 2 mol / L hydrochloric acid solution and stirred for 12 h. The solution was then repeatedly rinsed with distilled water until neutral and dried under vacuum at 80℃ for 12 h to obtain a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst, denoted as CM88-H.

[0041] Reference Figure 1 , Figure 1The XRD pattern of CM88-H shows no diffraction peaks for iron species. Only (002) and (101) plane diffraction peaks for carbon were observed at 2θ = 26° and 44°. The XRD results indicate that the acid washing step completely removed unstable iron species, and the iron content was below the XRD detection limit, indicating a high degree of graphitization in CM88-H. ICP-C analysis showed that the Fe loading in the example was 0.56%. AC-HAADFSTEM ( Figure 2 The results showed that iron existed in the examples in the form of single atoms and clusters. (The nitrogen desorption-adsorption isotherm diagram is shown.) Figure 3 As shown in figure a), the specific surface area of ​​CM88-H can be calculated to be 604.44 m². 2 / g, from the pore size distribution map ( Figure 3 As shown in b), after acid washing, the internal pore structure of the material is more abundant, and it is a multi-level pore structure containing micropores, mesopores and macropores.

[0042] Example 2

[0043] Using MIL-88B(Fe) as a precursor, the temperature was raised to 750℃ at a rate of 5℃ / min under a nitrogen atmosphere and held for 1.5 h, then cooled to room temperature. 50 mg of the prepared black carbonized MIL-88B(Fe) powder was added to 100 mL of 1 mol / L hydrochloric acid solution and stirred for 24 h. The solution was then repeatedly rinsed with distilled water until neutral and dried under vacuum at 70℃ for 15 h. The resulting catalyst was designated CM88-H1. In-cell plasma spectroscopy (ICP) analysis showed that the Fe loading in the example was 0.51%, and iron existed in the form of single atoms and clusters. Figure 4 (As shown).

[0044] Reference Figure 5 XAFS analysis of the catalyst showed that CM88-H1 contains Fe-N bonds and Fe-Fe bonds corresponding to iron oxides, indicating that iron exists in CM88-H1 in the form of single atoms and iron oxide clusters. The nitrogen desorption-adsorption isotherm diagram (…) Figure 6 As shown in figure a), the specific surface area of ​​CM88-H1 can be calculated to be 500.92 m². 2 / g, the internal pores are a hierarchical porous structure dominated by mesopores ( Figure 6 (as shown in b).

[0045] Example 3

[0046] Using MIL-53(Fe) as a precursor, the temperature was raised to 725℃ at a rate of 5℃ / min under an argon atmosphere and held for 1.5 h, then cooled to room temperature. 50 mg of carbonized MIL-53(Fe) powder was added to 100 mL of 5 mol / L nitric acid solution and stirred for 8 h. The solution was then repeatedly rinsed with distilled water until neutral and dried under vacuum at 60℃ for 24 h to obtain hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts. ICP testing showed that the Fe loading in the examples was 0.40%. Figure 7 As shown, in Example 3, iron exists in the form of single atoms and iron oxide clusters.

[0047] Example 4

[0048] Using MIL-101(Fe) as a precursor, the temperature was raised to 750℃ at a rate of 5℃ / min under a nitrogen atmosphere and held for 2 hours, then cooled to room temperature. 50 mg of carbonized MIL-101(Fe) was added to 100 mL of 3 mol / L hydrochloric acid solution and stirred for 10 hours. The solution was then repeatedly rinsed with distilled water until neutral and dried under vacuum at 100℃ for 6 hours to obtain hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts. ICP testing showed that the Fe loading in the examples was 0.60%. Figure 8 As shown, in Example 4, iron exists in the form of single atoms and iron oxide clusters.

[0049] Example 5

[0050] Using MIL-100(Fe) as a precursor, the temperature was raised to 725℃ at a rate of 5℃ / min under a nitrogen atmosphere and held for 2 hours, then cooled to room temperature. 50 mg of carbonized MIL-100(Fe) was added to 100 mL of 2.5 mol / L hydrochloric acid solution and stirred for 15 hours. The solution was then repeatedly rinsed with distilled water until neutral and dried under vacuum at 90℃ for 10 hours to obtain hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts. ICP testing showed that the Fe loading in the examples was 0.49%. Figure 9 As shown, in Example 5, iron exists in the form of single atoms and iron oxide clusters.

[0051] Application of the present invention of hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalysts

[0052] Example 1

[0053] The catalyst synthesized in Example 1 was used to activate potassium persulfate for the degradation of bisphenol A, bisphenol S, bisphenol F, and bisphenol fluorene. The specific steps were as follows: 7.5 mg of the prepared CM88-H catalyst was accurately weighed and rapidly dispersed in 50 mL of a 10 mg / L pollutant solution. Potassium persulfate stock solution was added to achieve a concentration of 0.05 g / L in the pollutant solution. Samples were taken at specified times for analysis. The degradation kinetic curves for each pollutant are shown below. Figure 10 As shown, all pollutants achieved a removal rate of over 90% within 15 minutes, indicating that the catalyst synthesized in Example 1 has excellent catalytic activation ability for persulfate oxidation of pollutants.

[0054] Example 2

[0055] The catalysts synthesized in Examples 1-5 were used to activate sodium persulfate for the degradation of bisphenol A, a typical representative of phenolic organic compounds. The initial concentration of bisphenol A in the system was 10 mg / L, the amount of catalyst added was 0.1 g / L, and the amount of sodium persulfate added was 0.1 g / L. The degradation kinetic curves are shown below. Figure 11 As shown, all catalysts exhibited excellent monopersulfate activation performance, and the catalytic effect was ranked as follows: Example 1 = Example 4 > Example 5 > Example 2 > Example 3. All catalysts could achieve efficient removal of bisphenol A.

[0056] The above detailed description is a specific description of feasible embodiments of the present invention. These embodiments are not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included in the patent scope of this case.

Claims

1. A method for preparing a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst for activating persulfate degradation of phenolic pollutants in the aquatic environment, characterized in that: Includes the following steps: S1. Preparation of iron-based metal-organic frameworks: The iron-based metal-organic frameworks are calcined at high temperature under a nitrogen or argon atmosphere to obtain iron-carbide metal-organic frameworks. S2. Add 50 mg of iron carbide-based metal-organic framework to 100 mL of acid solution, stir magnetically at room temperature for a certain period of time, and acid wash to remove unstable iron species. S3. The acid-washed iron carbide-based metal-organic framework is repeatedly rinsed with distilled water until neutral and then dried in a vacuum drying oven. S4. The powder obtained in step S3 is ground with an agate mortar to obtain a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst for the degradation of phenolic pollutants in the water environment by activated persulfate. The iron-based metal-organic framework mentioned in step S1 is any one of MIL-53, MIL-88B, MIL-100 and MIL-101; The hierarchical porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalyst described in step S4 for activating persulfate to degrade phenolic pollutants in the water environment have a hierarchical porous structure containing micropores, mesopores and macropores. The iron loading is 0.4-0.6%. The iron is uniformly dispersed on the support in the form of single atoms and iron oxide clusters. The N source in the Fe-N coordination bond is N,N-dimethylformamide, an organic solvent used in the solvothermal preparation of iron-based metal-organic frameworks. The high-temperature calcination temperature in step S1 is 700-750℃, and the high-temperature calcination time is 1.5-2h; The acid solution mentioned in step S2 is any one of hydrochloric acid, sulfuric acid, and nitric acid, with a concentration of 1-5 mol / L, and the magnetic stirring time is 8-24 h.

2. The preparation method according to claim 1, characterized in that: The preparation method of the iron-based metal-organic framework MIL-53 is as follows: accurately weigh 1.34 g of Fe(NO3)3·9H2O into a 100 mL polytetrafluoroethylene reactor, add 56 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.83 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 150 °C at a rate of 5 °C / min and maintain it for 15 h. After cooling to room temperature, wash three times with N,N-dimethylformamide and methanol by centrifugation, dry in a vacuum drying oven at 80 °C for 12 h, and grind with an agate mortar to obtain MIL-53 (Fe) solid powder. The preparation method of the iron-based metal-organic framework MIL-88B is as follows: 0.3108 g of FeCl3·6H2O is accurately weighed into a 100 mL polytetrafluoroethylene reactor, 25 mL of N,N-dimethylformamide is added, and the mixture is stirred at room temperature for 1 h. Then, 0.1911 g of H2BDC is added and the mixture is stirred for another 3 h to obtain a transparent, uniform, and stable mixed solution. After sealing the reactor, it is placed in a forced-air drying oven and heated to 150 °C at a rate of 5 °C / min and maintained for 12 h. After cooling to room temperature, the mixture is washed three times by centrifugation with N,N-dimethylformamide and methanol, respectively. It is then dried in a vacuum drying oven at 80 °C for 12 h and ground with an agate mortar to obtain MIL-88B (Fe) solid powder.

3. The preparation method according to claim 2, characterized in that: The preparation method of the iron-based metal-organic framework MIL-100 is as follows: accurately weigh 0.8104 g of Fe(NO3)3·9H2O into a 100 mL polytetrafluoroethylene reactor, add 30 mL of N,N-dimethylformamide, stir at room temperature for 1 h, then add 0.4983 g of H2BDC and continue stirring for 3 h to obtain a transparent, uniform and stable mixed solution. After sealing the reactor, place it in a forced-air drying oven, raise the temperature to 150℃ at a rate of 5℃ / min and maintain it for 10 h. After cooling to room temperature, wash three times with N,N-dimethylformamide and methanol by centrifugation, dry in a vacuum drying oven at 80℃ for 12 h, and grind with an agate mortar to obtain MIL-100 (Fe) solid powder. The preparation method of the iron-based metal-organic framework MIL-101 is as follows: 1.35 g of FeCl3·6H2O is accurately weighed into a 100 mL polytetrafluoroethylene reactor, 30 mL of N,N-dimethylformamide is added, and the mixture is stirred at room temperature for 1 h. Then, 0.415 g of H2BDC is added and the mixture is stirred for another 3 h to obtain a transparent, uniform, and stable mixed solution. After sealing the reactor, it is placed in a forced-air drying oven and heated to 110 °C at a rate of 5 °C / min and maintained for 24 h. After cooling to room temperature, the mixture is washed three times with ethanol and deionized water, and dried in a vacuum drying oven at 100 °C for 12 h. After grinding with an agate mortar, MIL-101 (Fe) solid powder is obtained.

4. The preparation method according to claim 1, characterized in that: The vacuum drying temperature in step S3 is 60-100℃, and the drying time is 6-24h.

5. A method for applying a hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst for activating persulfate degradation of phenolic pollutants in an aquatic environment, wherein the hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and iron single-atom catalyst for activating persulfate degradation of phenolic pollutants in an aquatic environment is obtained by the preparation method described in claim 1, characterized in that: A hierarchical porous nitrogen-doped carbon-supported iron oxide cluster and an iron single-atom catalyst were used to activate persulfate to degrade phenolic pollutants in the aquatic environment.

6. The method for applying the multi-level porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalyst for activating persulfate degradation of phenolic pollutants in the aquatic environment according to claim 5, characterized in that: The dosage of the multi-level porous nitrogen-doped carbon-supported iron oxide clusters and iron single-atom catalyst for degrading phenolic pollutants in the aquatic environment using activated persulfate is 0.05-0.2 g / L, and the dosage of persulfate is 0.025-0.2 g / L. The persulfate is any one or more of persulfate monosulfate and perdisulfate, and the phenolic pollutants are bisphenol A, bisphenol S, bisphenol F, and bisphenol fluorene. The time required for complete degradation of the pollutants is 5-30 min.

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