Preparation and application method of catalyst for oxidative degradation of antibiotic wastewater by room temperature activated peroxyacetic acid

Abstract

The application discloses a preparation method and application method of a room-temperature activated peracetic acid oxidative degradation antibiotic wastewater catalyst. The preparation method comprises the following steps: taking anhydrous manganese chloride and copper acetate monohydrate, dissolving in water, then adding hexagonal boron nitride powder and cetyltrimethylammonium bromide, stirring to obtain a mixed solution; the mixed solution is moved into a microwave synthesis reaction kettle for a synthesis reaction; after the reaction is completed, the synthesis product is washed, dried and ground to obtain a composite catalyst. The application method comprises the following steps: the hexagonal boron nitride nanosheet modified metal manganese element is used to replace the cupric oxychloride composite catalyst, and is added into a reactor containing antibiotic wastewater to be degraded; after adsorption equilibrium is reached, a peracetic acid solution is added to initiate the degradation reaction of the antibiotic. The catalyst prepared by the application has excellent ability of oxidatively degrading antibiotic wastewater in a room-temperature activated peracetic acid system, has strong environmental interference resistance, and has good reusability.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and relates to catalysts for the degradation of antibiotic wastewater, particularly a method for preparing and applying a room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater. This technology can effectively reduce the negative environmental impact of antibiotic wastewater and has significant environmental implications. Background Technology

[0002] Currently, global antibiotic consumption is experiencing rapid growth. Antibiotics primarily originate from use in medical, agricultural, and aquaculture fields. These antibiotic residues, once released into water bodies, can lead to elevated antibiotic concentrations in the aquatic environment, posing potential hazards. For example, they can have toxic effects on aquatic organisms and promote the development of antibiotic resistance in bacteria, increasing the risk of the spread of antibiotic-resistant bacteria in water. Even more concerning, they can pose potential health risks to humans. Advanced oxidation processes are a viable method for addressing antibiotic pollution in aquatic environments. They help degrade antibiotics into less toxic metabolites, reducing the risks to aquatic organisms and ecosystems.

[0003] Advanced oxidation processes (AOPs) based on peracetic acid (PAA) have promising applications in water treatment due to their high degradation efficiency and environmental compatibility. Peracetic acid (PAA), also known as acetyl hydroperoxide, is a strong oxidizing compound. Its chemical formula is CH3CO3H, composed of acetic acid (CH3COOH) and hydrogen peroxide (H2O2). It possesses strong oxidizing and bactericidal properties. Compared to H2O2-based AOPs, PAA exhibits better redox capabilities, with weaker O-OH bonds and smaller LUMOs, making it more susceptible to attacking bonds in organic compounds and thus enabling their degradation. Nevertheless, PAA's catalytic performance for the direct decomposition of organic pollutants is not high. Activation is commonly achieved through physical fields such as heating, microwave irradiation, ultrasound, and ultraviolet irradiation; however, in real-world water treatment, these methods typically involve high costs. Therefore, activation with transition metals is the most commonly used method.

[0004] Transition metal alkali salts (M2(OH)3Cl) have become a highly active emerging frontier in many fields such as hydrogen production, methane oxidation, and water-gas conversion, but their application in water treatment is rare. Therefore, this invention provides a method for preparing and applying a room-temperature activated catalyst for the oxidation and degradation of antibiotic wastewater by peracetic acid (PAA). It provides a composite catalyst modified with hexagonal boron nitride nanosheets, where manganese metal replaces some copper ions, introducing more active metal and promoting the formation of oxygen vacancies. The boron nitride nanosheets provide a stable support and promote electron transfer in the chemical reaction, all of which greatly enhance the oxidation capacity of the system, strengthen the ability of PAA to generate free radicals, promote the degradation of organic pollutants, and reduce the risk to aquatic organisms and ecosystems. Summary of the Invention

[0005] The first objective of this invention is to provide a catalyst with high catalytic performance, easy recovery, and applicable to the room-temperature activated peracetic acid oxidation degradation of antibiotic wastewater.

[0006] The second objective of this invention is to provide a method for preparing a catalyst with high catalytic performance, easy recovery, and applicable to the room-temperature activated peracetic acid oxidation degradation of antibiotic wastewater.

[0007] The third objective of this invention is to provide a method for applying a catalyst with high catalytic performance, easy recovery, and room temperature activated peracetic acid oxidation to degrade antibiotic wastewater.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] (I) This invention provides a method for preparing a room temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater, comprising the following steps: dissolving anhydrous manganese chloride and copper acetate monohydrate in water, then adding hexagonal boron nitride powder and hexadecyltrimethylammonium bromide, stirring to obtain a mixed solution; transferring the mixed solution into a microwave synthesis reactor for synthesis reaction; after the reaction is completed, washing the synthesized product to remove impurities, then drying and grinding to obtain a composite catalyst.

[0010] Furthermore, the ratio of anhydrous manganese chloride, copper acetate monohydrate, hexadecyltrimethylammonium bromide, and hexagonal boron nitride is (0-5.0336 g) g : (0-7.9864 g) g : (0.0182 g ~ 0.5824 g) g : (0-1.9856 g) g.

[0011] Furthermore, the ratio of anhydrous manganese chloride, copper acetate monohydrate, hexadecyltrimethylammonium bromide, and hexagonal boron nitride is 2.5168g:(0.9983-7.9864)g:(0.0182g~0.1452)g:(0.2482-1.9856)g.

[0012] Furthermore, the stirring speed of the mixed solution of anhydrous manganese chloride, copper acetate monohydrate, hexadecyltrimethylammonium bromide, and hexagonal boron nitride was 100–500 rpm, and the stirring time was 2–12 h.

[0013] Furthermore, the synthesis reaction time is 5–30 min, and the synthesis reaction temperature is 160–200 °C.

[0014] Furthermore, the washing method is as follows: wash four times alternately with deionized water and anhydrous ethanol.

[0015] Furthermore, the drying temperature is 30–70°C, and the drying time is 6–10 hours.

[0016] (ii) The present invention also provides a room temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater, which has the following characteristics: the catalyst is a hexagonal boron nitride nanosheet modified with manganese metal-substituted copper oxychloride composite catalyst, which is prepared by the preparation method described above.

[0017] (III) The present invention also provides a method for applying the above-described room temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater, which has the following characteristics: a composite catalyst of copper oxychloride replaced by hexagonal boron nitride nanosheets is added to a reactor containing antibiotic wastewater to be degraded. After reaching adsorption equilibrium, a peracetic acid solution is added to initiate the degradation reaction of antibiotics.

[0018] Furthermore, the mass ratio of the added hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst to the added peracetic acid is (0.015-0.05 g): (0.1-1 mmol).

[0019] Furthermore, the reaction temperature is room temperature (25±2℃), and the reaction time is (1-25min).

[0020] The beneficial effects of this invention are as follows:

[0021] 1. This invention synthesizes a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, wherein the doping of manganese metal replaces some copper ions, introduces more active metal, and promotes the formation of oxygen vacancies; the boron nitride nanosheets provide a stable support and promote electron transfer in the chemical reaction, all of which greatly improve the oxidation capacity of the system.

[0022] 2. The present invention prepares a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst. In the cyclic experiment, the leaching concentrations of manganese ions and copper ions are lower than the national wastewater discharge standards.

[0023] 3. The hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst prepared in this invention exhibits good catalytic oxidation ability in activated peracetic acid system, and can realize the oxidative degradation of a variety of antibiotics.

[0024] 5. The hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst prepared in this invention exhibits good stability and reusability. Even after multiple cycles in an activated peracetic acid system, it still demonstrates high degradation performance against antibiotics. Attached Figure Description

[0025] Figure 1 This is a SEM image of the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst in Example 1.

[0026] Figure 2 The image shows the FT-IR spectrum of the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst in Example 1.

[0027] Figure 3 EIS image of the hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst in Example 1;

[0028] Figure 4 The image shows the removal effect of the hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst activated at room temperature by peracetic acid oxidation and degradation of tetracycline.

[0029] Figure 5 The image shows the removal effect of the hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst on tetracycline hydrochloride under different pH conditions in Example 7.

[0030] Figure 6 This is a graph showing the effect of the hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst in Example 8 on the degradation of tetracycline after 5 cycles.

[0031] Figure 7 The concentration of metal elements leached after each cycle of the tetracycline degradation experiment using the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst in Example 8 is shown. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the reagents, methods, and equipment used are conventional reagents, methods, and equipment in this technical field.

[0033] Example 1

[0034] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting tetracycline as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0035] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0036] Measure 2.5168 g of anhydrous manganese chloride and 0.9983 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.9928 g of hexagonal boron nitride and 0.0364 g of cetyltrimethylammonium bromide and stir at 500 rpm for 5 h to obtain a mixed solution.

[0037] The above mixed solution was transferred to a microwave reactor and reacted at 180°C for 30 min under microwave-assisted hydrothermal conditions.

[0038] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0039] The hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst was characterized, and the SEM, FT-IR, and EIS images are shown below. Figure 1-3 As shown.

[0040] (2) Oxidative degradation of antibiotics:

[0041] 0.04 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of a reactor containing tetracycline hydrochloride wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 500 rpm. After reaching adsorption equilibrium (time 30 min), 0.7 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 15 min.

[0042] Samples were taken at 1, 5, 7, 10, and 15 minutes, with the removal rate of tetracycline hydrochloride used as the evaluation index. The concentration of tetracycline hydrochloride was determined by HPLC, and the results are shown below. Figure 4 .Depend on Figure 4 It can be seen that the removal rate of tetracycline hydrochloride reached 97.18% after 15 minutes of reaction.

[0043] Example 2

[0044] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting sulfadiazine as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0045] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0046] Measure 2.5168 g of anhydrous manganese chloride and 3.9932 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.2482 g of hexagonal boron nitride and 0.0182 g of cetyltrimethylammonium bromide and stir at 500 rpm for 5 h to obtain a mixed solution.

[0047] The above mixed solution was transferred to a microwave reactor and reacted at 180°C for 20 min under microwave-assisted hydrothermal conditions.

[0048] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0049] (2) Oxidative degradation of antibiotics:

[0050] 0.03 g of hexagonal boron nitride nanosheets-modified manganese-substituted copper oxychloride composite catalyst was added to 100 mL of sulfadiazine wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 500 rpm until adsorption equilibrium was reached (time 30 min). Then, 0.8 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 20 min.

[0051] Samples were taken every 5 minutes, with the removal rate of sulfadiazine used as the evaluation index. The concentration of sulfadiazine was determined by HPLC, and the removal rate of sulfadiazine reached 88.67% after 20 minutes of reaction.

[0052] Example 3

[0053] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting sulfamethoxazole as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0054] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0055] Measure 2.5168 g of anhydrous manganese chloride and 7.9864 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.4964 g of hexagonal boron nitride and 0.0728 g of cetyltrimethylammonium bromide and stir at 500 rpm for 6 h to obtain a mixed solution.

[0056] The above mixed solution was transferred to a microwave reactor and reacted at 170°C for 30 min under microwave-assisted hydrothermal conditions.

[0057] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0058] (2) Oxidative degradation of antibiotics:

[0059] 0.03 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of sulfamethoxazole wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 350 rpm until adsorption equilibrium was reached (time 30 min). Then, 0.8 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 20 min.

[0060] Samples were taken every 5 minutes, with the removal rate of sulfamethoxazole used as the evaluation index. The concentration of sulfamethoxazole was determined by HPLC, and the removal rate of sulfamethoxazole reached 84.67% after 20 minutes of reaction.

[0061] Example 4

[0062] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting ciprofloxacin as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0063] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0064] Measure 2.5168 g of anhydrous manganese chloride and 6.7114 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.6618 g of hexagonal boron nitride and 0.04853 g of cetyltrimethylammonium bromide and stir at 400 rpm for 5 h to obtain a mixed solution.

[0065] The above mixed solution was transferred to a microwave reactor and reacted at 190°C for 30 min under microwave-assisted hydrothermal conditions.

[0066] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0067] (2) Oxidative degradation of antibiotics:

[0068] 0.02 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of ciprofloxacin wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 300 rpm. After reaching adsorption equilibrium (time 30 min), 1 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 25 min.

[0069] Samples were taken every 5 minutes, with the removal rate of ciprofloxacin used as the evaluation index. The concentration of ciprofloxacin was determined by HPLC, and the removal rate of ciprofloxacin reached 76.73% after 25 minutes of reaction.

[0070] Example 5

[0071] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting norfloxacin as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0072] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0073] Measure 2.5168 g of anhydrous manganese chloride and 1.9966 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.4946 g of hexagonal boron nitride and 0.1452 g of hexadecyltrimethylammonium bromide and stir for 5 h to obtain a mixed solution.

[0074] The above mixed solution was transferred to a microwave reactor and reacted at 200°C for 20 min under microwave-assisted hydrothermal conditions.

[0075] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was dried in an oven at 50℃ for 10 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0076] (2) Oxidative degradation of antibiotics:

[0077] 0.02 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of norfloxacin wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 300 rpm until adsorption equilibrium was reached (time 30 min). Then, 1 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 25 min.

[0078] Samples were taken every 5 minutes, with the removal rate of norfloxacin used as the evaluation index. The concentration of norfloxacin was determined by HPLC, and the removal rate of norfloxacin reached 71.74% after 25 minutes of reaction.

[0079] Example 6

[0080] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting bisphenol A as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0081] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0082] Measure 2.5168 g of anhydrous manganese chloride and 3.7752 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.7942 g of hexagonal boron nitride and 0.0364 g of cetyltrimethylammonium bromide and stir for 10 h to obtain a mixed solution.

[0083] The above mixed solution was transferred to a microwave reactor and reacted at 180°C for 15 min under microwave-assisted hydrothermal conditions.

[0084] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0085] (2) Oxidative degradation of antibiotics:

[0086] 0.04 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of bisphenol A wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 500 rpm until adsorption equilibrium was reached (time was 30 min). Then, 0.5 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 15 min.

[0087] Samples were taken at 1, 5, 7, 10, and 15 minutes, with the removal rate of bisphenol A used as the evaluation index. The concentration of bisphenol A was measured using a UV spectrophotometer, and the removal rate of bisphenol A reached 91.64% after 15 minutes of reaction.

[0088] Example 7

[0089] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting tetracycline hydrochloride as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0090] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0091] Measure 2.5168 g of anhydrous manganese chloride and 0.9983 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 0.2482 g of hexagonal boron nitride and 0.0182 g of hexadecyltrimethylammonium bromide and stir for 5 h to obtain a mixed solution.

[0092] The above mixed solution was transferred to a microwave reactor and reacted at 170°C for 20 min under microwave-assisted hydrothermal conditions.

[0093] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0094] (2) Oxidative degradation of antibiotics by hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst under different pH conditions:

[0095] 0.04 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst were added to 100 mL reactors containing tetracycline hydrochloride wastewater (concentration 10 mg / L) to be degraded at initial pH values ​​of 3, 5, 7, 9, and 11, respectively. After reaching adsorption equilibrium at a rotation speed of 500 rpm (time 30 min), 0.5 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 15 min.

[0096] Samples were taken at 1, 5, 7, 10, and 15 minutes, with the removal rate of tetracycline hydrochloride used as the evaluation index. The concentration of tetracycline hydrochloride was determined by HPLC, and the results are as follows: Figure 5 As shown, the degradation of tetracycline hydrochloride was inhibited at pH 3, while the degradation of tetracycline hydrochloride was hardly inhibited at pH 5-11.

[0097] The results show that the present invention has excellent degradation ability of organic pollutants over a relatively wide pH range.

[0098] Example 8

[0099] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting tetracycline hydrochloride as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0100] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0101] Measure 2.5168 g of anhydrous manganese chloride and 6.3892 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 1.9856 g of hexagonal boron nitride and 0.1162 g of hexadecyltrimethylammonium bromide and stir for 8 h to obtain a mixed solution.

[0102] The above mixed solution was transferred to a microwave reactor and reacted at 180°C for 25 min under microwave-assisted hydrothermal conditions.

[0103] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0104] (2) Stability and repeatability tests of the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst:

[0105] 0.05 g of hexagonal boron nitride nanosheets modified with manganese-substituted copper oxychloride composite catalyst was added to 100 mL of a reactor containing tetracycline hydrochloride wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 450 rpm. After reaching adsorption equilibrium (time 30 min), 0.7 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 15 min.

[0106] Samples were taken every 5 minutes, with the removal rate of tetracycline hydrochloride used as the evaluation index. The concentration of tetracycline hydrochloride was determined by HPLC. After the reaction, the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst was recovered for regeneration, and antibiotic degradation experiments were continued. The results of repeated degradation experiments are shown below. Figure 6 As shown, after repeating the process five times, the removal efficiency of tetracycline hydrochloride remained above 80%.

[0107] In addition, by detecting the leaching concentration of metal elements after each cycle of the experiment, reference was made. Figure 7 It was found that the leaching concentrations of metallic manganese and copper were both lower than the national standard (GT 31962-2015).

[0108] Example 9

[0109] This embodiment prepares a hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst, and uses it as a catalyst to activate a peracetic acid system at room temperature, selecting tetracycline hydrochloride as the target pollutant for the oxidative degradation of antibiotics. The specific technical solution is as follows:

[0110] (1) Synthesis of a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets:

[0111] Measure 2.5168 g of anhydrous manganese chloride and 6.3892 g of copper acetate monohydrate and dissolve them in 20 mL of ultrapure water. Then add 1.9856 g of hexagonal boron nitride and 0.1162 g of hexadecyltrimethylammonium bromide and stir for 8 h to obtain a mixed solution.

[0112] The above mixed solution was transferred to a microwave reactor and reacted at 180°C for 30 min under microwave-assisted hydrothermal conditions.

[0113] After the reaction was completed, the supernatant was discarded, and the mixture was cooled to room temperature. It was then washed four times with anhydrous ethanol and distilled water, and centrifuged at 5000 r / min for 3 min. After that, it was placed in a 50℃ oven to dry for 8 h, ground and sieved to obtain a hexagonal boron nitride nanosheet modified manganese-substituted copper oxychloride composite catalyst.

[0114] (2) Oxidative degradation of antibiotics:

[0115] 0.05 g of hexagonal boron nitride nanosheets-modified manganese-substituted copper oxychloride composite catalyst was added to 100 mL of a reactor containing tetracycline hydrochloride wastewater (concentration 10 mg / L) to be degraded. The reaction was carried out at 450 rpm until adsorption equilibrium was reached (time 30 min). Then, 0.8 mM peracetic acid solution was added to initiate the reaction. The reaction temperature was 25 ± 2 °C and the reaction time was 15 min.

[0116] Samples were taken every 5 minutes, with the removal rate of tetracycline hydrochloride used as the evaluation index. The concentration of tetracycline hydrochloride was determined by HPLC, and the removal rate of tetracycline hydrochloride reached 97.18% after 15 minutes of reaction.

[0117] In addition, a comparative experiment was conducted. 0.8 mM peracetic acid solution was added to 100 mL of a reactor containing tetracycline hydrochloride wastewater (concentration of 10 mg / L) to be treated (without adding a catalyst). The concentration of tetracycline hydrochloride was determined by HPLC. After 15 min of reaction, the removal rate of tetracycline hydrochloride was only 11.12%.

[0118] This invention uses manganese metal to replace copper in copper oxychloride, introducing an active metal to promote the formation of oxygen vacancies. Simultaneously, hexagonal boron nitride is used as a support, which increases structural stability and promotes electron transfer during the chemical reaction, thereby enhancing the ability to activate PAA to generate free radicals and promoting the degradation of organic pollutants. In the degradation of various types of antibiotic wastewater, the hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst achieved a degradation performance of 71.74-97.17% in the peracetic acid system activated at room temperature. Furthermore, in the cyclic experiment of degrading tetracycline hydrochloride, the catalyst itself also exhibited excellent reusability, and the metal leaching rate during the recycling process was lower than the national standard limit.

[0119] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within the scope of its essence and protection. Such modifications or equivalent substitutions should also be considered to fall within the protection scope of the present invention.

Claims

1. A method for preparing a room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater, characterized in that, Includes the following steps: Anhydrous manganese chloride and copper acetate monohydrate were dissolved in water, and then hexagonal boron nitride powder and hexadecyltrimethylammonium bromide were added and stirred to obtain a mixed solution. The mixed solution was transferred into a microwave synthesis reactor to carry out the synthesis reaction; After the reaction was completed, the synthesized product was washed, dried and ground to obtain the composite catalyst; The ratio of anhydrous manganese chloride, copper acetate monohydrate, hexadecyltrimethylammonium bromide, and hexagonal boron nitride is (2.5168-5.0336) g : (0.9983-7.9864) g : (0.0182-0.5824) g : (0.2482-1.9856) g; the synthesis reaction time is 5-30 min, and the synthesis reaction temperature is 160-200℃. The catalyst is a composite catalyst of manganese-substituted copper oxychloride modified with hexagonal boron nitride nanosheets.

2. The preparation method of the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater according to claim 1, characterized in that, The stirring speed of the mixed solution of anhydrous manganese chloride, copper acetate monohydrate, hexadecyltrimethylammonium bromide, and hexagonal boron nitride was 100~500 rpm, and the stirring time was 2~12 h.

3. The preparation method of the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater according to claim 1, characterized in that, The washing method is as follows: wash with deionized water and anhydrous ethanol alternately 4 times.

4. The preparation method of the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater according to claim 1, characterized in that, The drying temperature is 30~70℃, and the drying time is 6~10h.

5. The room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater prepared by the preparation method according to any one of claims 1 to 4.

6. The method for applying the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater as described in claim 5, characterized in that, include: A composite catalyst of copper oxychloride replaced by manganese metal modified with hexagonal boron nitride nanosheets was added to a reactor containing antibiotic wastewater to be degraded. After adsorption equilibrium was reached, peracetic acid solution was added to initiate the degradation reaction of the antibiotics.

7. The method for applying the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater according to claim 6, characterized in that, The mass ratio of the added hexagonal boron nitride nanosheet-modified manganese-substituted copper oxychloride composite catalyst to the added peracetic acid was (0.015-0.05 g): (0.1-1 mmol).

8. The method for applying the room-temperature activated peracetic acid oxidative degradation catalyst for antibiotic wastewater according to claim 6, characterized in that, include: The reaction temperature is 25±2℃, and the reaction time is 1-25 min.

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