A photocatalytic self-fenton water treatment method based on graphene / self-assembled tetra (4-carboxyphenyl) porphyrin

Abstract

The application belongs to the technical field of environmental material preparation, and relates to a photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl) porphyrin (rGO / SA-TCPP). Self-assembled tetracarboxyphenyl porphyrin (SA-TCPP) is prepared by a supramolecular self-assembly method, and the rGO / SA-TCPP photocatalyst is prepared by an in-situ self-assembly method; then, Fe salt and the photocatalyst are added to the reaction system to construct a photocatalytic self-Fenton system for water treatment. The rGO introduced in the prepared rGO / SA-TCPP can effectively enhance the light absorption capacity, increase the number of surface active sites, and accelerate the separation and migration rate of photo-generated charges, thereby improving the ability of the rGO / SA-TCPP to in-situ synthesize H2O2 through two reaction pathways, i.e., the reduction of O2 by photo-generated electrons and the thermal decomposition of peroxycarboxylic acid intermediates by photo-generated holes oxidizing carboxylic acid groups in the structure of SA-TCPP. The photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP realizes efficient removal of antibiotics, drug-resistant bacteria and resistance genes in water.

Description

Technical Field

[0001] This invention relates to a photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin (rGO / SA-TCPP), belonging to the fields of environmental chemistry and materials science. Background Technology

[0002] Developing green, simple, and efficient treatment technologies to improve the removal of antibiotics, ARBs, and ARGs from water bodies is of great significance for controlling antibiotic resistance pollution in the environment.

[0003] In recent years, advanced oxidation technologies, represented by Fenton oxidation and photocatalytic oxidation, have attracted widespread attention worldwide. However, the Fenton process still faces challenges. 3+ / Fe 2+ The traditional Chinese medicine (TCM) method suffers from problems such as low recycling conversion rate, large H2O2 dosage, narrow pH range, and easy formation of iron sludge. Meanwhile, photocatalytic oxidation still faces challenges including low utilization of solar energy by photocatalysts, low separation and migration rates of photogenerated carriers, and unsatisfactory oxidation capacity and mineralization efficiency, thus limiting its application prospects in water treatment. The photocatalytic self-Fenton technology, a combination of Fenton and photocatalysis, effectively solves these problems. This technology primarily utilizes a photocatalyst for in-situ efficient synthesis of H2O2, then promotes a heterogeneous self-Fenton reaction mediated by Fe, converting H2O2 into a large number of hydroxyl radicals (·OH). The reducing power of photogenerated electrons promotes the reaction process by increasing Fe content in the reaction system. 3+ / Fe 2+ The cyclic transformation improves the efficiency of H2O2 to ·OH conversion, while reducing the recombination probability of its own photogenerated charges and releasing more free photogenerated holes to participate in the oxidation reaction; thus, a photocatalytic self-Fenton water treatment method with stronger oxidation capacity and higher mineralization efficiency is developed, resulting in a more significant removal effect on antibiotics, drug-resistant bacteria and resistance genes in water.

[0004] Self-assembled tetra(4-carboxyphenyl)porphyrin (SA-TCPP) photocatalysts possess advantages such as a wide visible light response range, abundant elemental sources, easily tunable structure, and high stability, making them widely applicable in fields such as organic matter degradation, pathogenic bacteria elimination, and H2O2 synthesis. They have become an excellent carrier for constructing photocatalytic self-Fenton synergistic reaction systems. However, SA-TCPP particles prepared by supramolecular self-assembly are small in size and prone to aggregation, resulting in a high probability of photogenerated charge recombination and affecting their photocatalytic activity. Therefore, modifying SA-TCPP using appropriate methods to further improve its photocatalytic activity and meet the requirements for constructing photocatalytic self-Fenton reaction systems is key to solving this problem. Summary of the Invention

[0005] To address the aforementioned problems in existing technologies, this invention prepares an rGO / SA-TCPP composite photocatalyst via in-situ self-assembly. Then, by adding Fe salt to the reaction system, a photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP is developed. The introduction of rGO into the rGO / SA-TCPP prepared in this invention effectively enhances its light absorption capacity, increases the number of surface active sites, and accelerates the separation and migration rate of photogenerated charges. This, in turn, improves the ability of rGO / SA-TCPP to synthesize H2O2 in situ through two reaction pathways: photogenerated electron reduction of O2 and photogenerated hole oxidation of the carboxylic acid group in the SA-TCPP structure to form a peroxycarboxylic acid intermediate, followed by thermal decomposition. This addresses the problems existing in current SA-TCPP photocatalysts and photocatalytic self-Fenton technology.

[0006] The purpose of this invention is to provide a photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin.

[0007] The water treatment method is as follows: graphene / self-assembled tetra(4-carboxyphenyl)porphyrin photocatalyst is added to the wastewater to be treated, the pH and temperature of the reaction system are adjusted, Fe salt is added to the reaction system to construct a photocatalytic self-Fenton system, the reaction system is placed under a light source for irradiation, and continuous aeration is carried out to keep the solution in an oxygen-saturated state.

[0008] The method for preparing the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin is as follows:

[0009] Step 1: Disperse tetra(4-carboxyphenyl)porphyrin in an alkaline solution, heat and stir until the solid is completely dissolved, add acid solution, adjust pH, heat and stir until precipitation stops, and prepare self-assembled tetra(4-carboxyphenyl)porphyrin dispersion, i.e., SA-TCPP dispersion;

[0010] Step 2: Prepare graphene oxide dispersion, i.e., GO dispersion;

[0011] Step 3: Mix the SA-TCPP dispersion, GO dispersion and reducing agent solution, sonicate, then heat and stir. After the reaction is complete, separate and purify, dry and grind to prepare graphene / self-assembled tetra(4-carboxyphenyl)porphyrin, which is rGO / SA-TCPP photocatalyst.

[0012] In one embodiment, the rGO / SA-TCPP photocatalyst is added to the wastewater to be treated and then ultrasonically dispersed. The ultrasonic power is 200-800W, the ultrasonic frequency is 10-50kHz, and the ultrasonic time is 0.1-10h.

[0013] In one embodiment, the mass ratio of rGO / SA-TCPP photocatalyst to Fe salt is 1:0.005-20, the pH of the reaction system is 1-14, and the reaction temperature is 0-100℃.

[0014] In one embodiment, the mass ratio of rGO / SA-TCPP photocatalyst to Fe salt is less than 5:2.

[0015] In one embodiment, the mass ratio of rGO / SA-TCPP photocatalyst to Fe salt is 15:4.

[0016] In one embodiment, the pH of the reaction system is 5 to 8.

[0017] In one embodiment, the Fe salt includes ferric chloride, ferrous chloride, ferric nitrate, ferrous nitrate, ferric sulfate, or ferrous sulfate.

[0018] The introduced gas includes oxygen, air, or a mixture of oxygen and argon, and the gas flow rate is 0.1 to 10 mL / min;

[0019] Light sources include LED lamps, xenon lamps, high-pressure mercury lamps, metal halide lamps, or sunlight.

[0020] In one embodiment, after adjusting the pH and temperature of the reaction system, the mixture is stirred to reach adsorption-desorption equilibrium. The stirring speed is 50–1500 r / min, and the stirring time is 0.1–10 h.

[0021] In one embodiment, step 1 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method includes:

[0022] The mass-to-volume ratio (mg / mL) of the tetra(4-carboxyphenyl)porphyrin to the alkaline solution is 1:0.01–100;

[0023] The stirring speed is 50–1500 r / min, and the stirring time is 0.1–10 h;

[0024] The rate at which the acid solution is added is 0.1–100 mL / min;

[0025] The pH of the reaction system is 1 to 10;

[0026] The heating temperature is 30–100°C.

[0027] In one embodiment, step 1 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method:

[0028] The alkaline solution includes potassium hydroxide, sodium hydroxide, sodium carbonate, or sodium bicarbonate solution;

[0029] Acid solutions include hydrochloric acid, sulfuric acid, nitric acid, or acetic acid solutions.

[0030] In one embodiment, step 2 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method involves: obtaining a GO dispersion by dispersing graphene oxide in water and then ultrasonicating it.

[0031] The mass-to-volume ratio of the oxidized graphite to water (mg / mL) is 1:0.01 to 100;

[0032] The ultrasonic power is 200–800W, the ultrasonic frequency is 10–50kHz, and the ultrasonic time is 0.1–10h.

[0033] In one embodiment, step 3 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method:

[0034] The mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:0.1 to 1000, and the mass ratio of graphene oxide to reducing agent is 1:0.01 to 10.

[0035] The ultrasonic power is 200–800W, the ultrasonic frequency is 10–50kHz, and the ultrasonic time is 0.1–10h.

[0036] The heating temperature is 30–100°C; the stirring speed is 50–1500 r / min, and the stirring time is 0.1–10 h.

[0037] The separation and purification process includes centrifugation followed by precipitate washing; the centrifugation speed is 1000–15000 r / min;

[0038] The drying method is atmospheric pressure drying, vacuum drying or freeze drying, the drying temperature is 0 to 100°C, the drying time is 1 to 50 hours, and the grinding time is 0.1 to 10 hours.

[0039] In one embodiment, in step 3 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method: the reducing agent includes ascorbic acid, glucose or sodium citrate, and the concentration of the reducing agent is 0.01-100 mg / mL.

[0040] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:200.

[0041] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:100.

[0042] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:50.

[0043] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 3:100.

[0044] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:25.

[0045] In one embodiment, the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:20.

[0046] The aforementioned photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin is used to remove one or more of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics, one or more of sulfonamide-resistant bacteria, quinolone-resistant bacteria, and tetracycline-resistant bacteria, and one or more of sulfonamide resistance genes, quinolone resistance genes, and tetracycline resistance genes from water.

[0047] Beneficial effects:

[0048] (1) The rGO / SA-TCPP photocatalyst prepared in this invention has superior performance in synthesizing H2O2, degrading antibiotics, killing drug-resistant bacteria and removing resistance genes compared with the SA-TCPP photocatalyst.

[0049] (2) The photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP developed in this invention has superior performance in degrading antibiotics, killing drug-resistant bacteria and removing resistance genes compared with Fenton alone and photocatalytic water treatment methods.

[0050] (3) The method described in this invention has mild reaction conditions, simple process, high versatility and good stability, and is a green and efficient new water treatment technology.

[0051] This invention prepares an rGO / SA-TCPP composite photocatalyst via in-situ self-assembly. On one hand, the introduction of rGO promotes the uniform dispersion of SA-TCPP particles on the surface of its two-dimensional nanosheets, thereby exposing more active sites, increasing surface activity, and enhancing the composite photocatalyst's adsorption capacity for O2 and pollutants. This accelerates the reaction of photogenerated charges participating in the synthesis of H2O2 and the removal of pollutants. The introduction of rGO also enhances the light absorption capacity of the composite photocatalyst, leading to the generation of more photogenerated charges participating in the reaction. As an electron acceptor, rGO can improve the separation and migration rate of photogenerated charges in the composite photocatalyst, effectively suppressing the recombination probability of electron-hole pairs. This significantly improves the ability of the rGO / SA-TCPP composite photocatalyst to synthesize H2O2 in situ via two reaction pathways: photogenerated electron reduction of O2 and photogenerated hole oxidation of the carboxylic acid groups in the SA-TCPP structure to a peroxycarboxylic acid intermediate followed by thermal decomposition. On the other hand, this invention constructs a photocatalytic self-Fenton synergistic system based on rGO / SA-TCPP by adding Fe salt to the rGO / SA-TCPP reaction system. Photogenerated electrons can promptly convert Fe... 3+ Reduced to Fe 2+ Promote Fe 3+ / Fe 2+ The cyclic conversion significantly improves the in-situ production of H2O2 and Fe by rGO / SA-TCPP. 2+ The efficiency of generating ·OH through the self-Fenton reaction further enhances the oxidation capacity of the reaction system. Simultaneously, the consumption of photogenerated electrons successfully suppresses the recombination of its own photogenerated charges, releasing more free photogenerated holes to participate in the oxidation reaction, further enhancing the mineralization efficiency of the reaction system. Under the synergistic effect of a large amount of ·OH and photogenerated holes, the rGO / SA-TCPP-based photocatalytic self-Fenton water treatment method achieves highly efficient removal of antibiotics, ARBs, and ARGs from water. Therefore, this invention develops a rGO / SA-TCPP-based photocatalytic self-Fenton water treatment method with strong oxidation capacity and high mineralization efficiency without the addition of H2O2, achieving better environmental purification effects and higher application value than Fenton and photocatalytic water treatment methods alone. Attached Figure Description

[0052] Figure 1 The graphs show the photocatalytic degradation performance of sulfadimethoxypyrimidine by rGO / SA-TCPP prepared in Examples 1-6, SA-TCPP prepared in Comparative Example 1, g-C3N4 prepared in Comparative Example 3, and 3% rGO / SA-TCPP (physical mixture) prepared in Comparative Example 4 under visible light; where (a) is the degradation activity curve and (b) is the apparent rate constant.

[0053] Figure 2A comparison chart of the H2O2 synthesis performance of 3% rGO / SA-TCPP prepared in Example 1 and SA-TCPP prepared in Comparative Example 1.

[0054] Figure 3 The graph shows the cyclic synthesis performance of H2O2 using 3% rGO / SA-TCPP prepared in Example 1.

[0055] Figure 4 The graph shows a comparison of the degradation performance of sulfadimethoxypyrimidine by the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP prepared in Example 1 under different conditions; where (a) under different types of Fe salts, (b) under different amounts of Fe salts added, and (c) under different pH conditions.

[0056] Figure 5 The graph shows a comparison of the degradation of sulfadiazine and its total organic carbon (TOC) removal rates of the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6; where (a) degradation activity curve, (b) apparent rate constant, and (c) TOC removal rate.

[0057] Figure 6 The graph shows a comparison of the degradation of sulfadiazine using the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6; where (a) is the degradation activity curve and (b) is the apparent rate constant.

[0058] Figure 7 This is a cyclic degradation activity diagram of the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7.

[0059] Figure 8 The graph shows a comparison of the photocatalytic water treatment performance of the 3% rGO / SA-TCPP prepared in Example 1, the SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6 in killing sulfonamide ARBs.

[0060] Figure 9 The graph shows a comparison of the performance of the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6 in removing sulfonamide ARGs.

[0061] Figure 10 The images show TEM comparisons of 3% rGO / SA-TCPP prepared in Example 1 with SA-TCPP prepared in Comparative Example 1 and rGO prepared in Comparative Example 2; where (a) is rGO, (b) is SA-TCPP and (c) is 3% rGO / SA-TCPP.

[0062] Figure 11 The XRD patterns are comparison images of rGO / SA-TCPP prepared in Examples 1-6 with SA-TCPP prepared in Comparative Example 1 and rGO prepared in Comparative Example 2.

[0063] Figure 12 The image shows a comparison of FTIR values ​​of rGO / SA-TCPP prepared in Examples 1-6 with SA-TCPP prepared in Comparative Example 1 and rGO prepared in Comparative Example 2.

[0064] Figure 13 Raman comparison images of 3% rGO / SA-TCPP prepared in Example 1, SA-TCPP prepared in Comparative Example 1, and rGO prepared in Comparative Example 2.

[0065] Figure 14 DRS comparison chart of 3% rGO / SA-TCPP prepared in Example 1, SA-TCPP prepared in Comparative Example 1, and rGO prepared in Comparative Example 2.

[0066] Figure 15 The graph shows a comparison of the photoelectric conversion performance of the 3% rGO / SA-TCPP prepared in Example 1 and the SA-TCPP prepared in Comparative Example 1; where (a) is the photocurrent response under alternating light and dark conditions; and (b) is the electrochemical impedance Nyquist plot under visible light.

[0067] Figure 16 This is a comparison of the degradation performance of sulfadimethoxypyrimidine by the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7 after the addition of different active species capture agents. Detailed Implementation

[0068] The following embodiments further illustrate the content of the present invention, but should not be construed as limiting the present invention. Any modifications and substitutions made to the methods, steps, or conditions of the present invention without departing from the spirit and essence of the present invention are within the scope of the present invention.

[0069] Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0070] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0071] Example 1

[0072] A method for preparing an rGO / SA-TCPP photocatalyst includes the following steps:

[0073] (1) 100 mg of tetra(4-carboxyphenyl)porphyrin powder was dispersed in 71.43 mL of 0.05 mol / L potassium hydroxide solution and heated and stirred at 50 °C and 500 r / min for 0.5 h until the solid was completely dissolved. Then, 0.05 mol / L hydrochloric acid solution was added to the solution at a rate of 1 mL / min until pH = 7. The solution was heated and stirred at 50 °C and 500 r / min for 1 h until precipitation stopped, thus preparing SA-TCPP dispersion.

[0074] (2) Disperse graphene oxide powder in ultrapure water and sonicate (560W, 40kHz) for 2h to prepare a 1mg / mL GO dispersion.

[0075] (3) Add 3 mL of GO dispersion and 3 mL of 1 mg / mL ascorbic acid solution to the SA-TCPP dispersion obtained in step (1), sonicate (560 W, 40 kHz) for 1 h, heat and stir at 80 °C and 500 r / min for 4 h, centrifuge (8000 r / min) to collect the precipitate after the reaction is completed, wash the precipitate several times with ultrapure water, vacuum dry at 60 °C for 24 h, and finally grind by hand for 1 h. The obtained product is recorded as 3% rGO / SA-TCPP photocatalyst.

[0076] Example 2

[0077] Example 2 is basically the same as Example 1, except that the mass ratio of GO to SA-TCPP is 1:200. The remaining steps and raw materials are the same as in Example 1. The resulting product is denoted as 0.5% rGO / SA-TCPP photocatalyst.

[0078] Example 3

[0079] Example 3 is basically the same as Example 1, except that the mass ratio of GO to SA-TCPP is 1:100. The remaining steps and raw materials are the same as in Example 1. The resulting product is denoted as 1% rGO / SA-TCPP photocatalyst.

[0080] Example 4

[0081] Example 4 is basically the same as Example 1, except that the mass ratio of GO to SA-TCPP is 1:50. The remaining steps and raw materials are the same as in Example 1. The resulting product is denoted as 2% rGO / SA-TCPP photocatalyst.

[0082] Example 5

[0083] Example 5 is basically the same as Example 1, except that the mass ratio of GO to SA-TCPP is 1:25. The remaining steps and raw materials are the same as in Example 1. The resulting products are denoted as 4% rGO / SA-TCPP photocatalysts.

[0084] Example 6

[0085] Example 6 is basically the same as Example 1, except that the mass ratio of GO to SA-TCPP is 1:20. The remaining steps and raw materials are the same as in Example 1. The resulting products are denoted as 5% rGO / SA-TCPP photocatalysts.

[0086] Example 7

[0087] A photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP includes the following steps:

[0088] (1) 100 mg of tetra(4-carboxyphenyl)porphyrin powder was dispersed in 71.43 mL of 0.05 mol / L potassium hydroxide solution and heated and stirred at 50 °C and 500 r / min for 0.5 h until the solid was completely dissolved. Then, 0.05 mol / L hydrochloric acid solution was added to the solution at a rate of 1 mL / min until pH = 7. The solution was heated and stirred at 50 °C and 500 r / min for 1 h until precipitation stopped, thus preparing SA-TCPP dispersion.

[0089] (2) Disperse graphene oxide powder in ultrapure water and sonicate (560W, 40kHz) for 2h to prepare a 1mg / mL GO dispersion.

[0090] (3) Add 3 mL of GO dispersion and 3 mL of 1 mg / mL ascorbic acid solution to the SA-TCPP dispersion obtained in step (1), sonicate (560 W, 40 kHz) for 1 h, heat and stir at 80 °C and 500 r / min for 4 h, centrifuge (8000 r / min) to collect the precipitate after the reaction, wash the precipitate several times with ultrapure water, vacuum dry at 60 °C for 24 h, and finally grind by hand for 1 h. The obtained product is recorded as 3% rGO / SA-TCPP photocatalyst.

[0091] (4) Add 15 mg of 3% rGO / SA-TCPP photocatalyst to the wastewater to be treated, disperse it by ultrasonication (560 W, 40 kHz) for 0.5 h, adjust the pH of the reaction system to 6 and the temperature to 60 °C, stir at 500 r / min for 1 h to reach adsorption-desorption equilibrium, add 4 mg of ferric chloride (the mass ratio of 3% rGO / SA-TCPP photocatalyst to Fe salt is 15:4) to the reaction system, and then place the reaction system under an LED lamp for irradiation to initiate the photocatalytic self-Fenton reaction based on 3% rGO / SA-TCPP. During the reaction, oxygen is continuously introduced (1 mL / min) to keep the solution in an oxygen-saturated state.

[0092] Example 8

[0093] A photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP includes the following steps:

[0094] (1) Disperse 100 mg of tetra(4-carboxyphenyl)porphyrin powder in 1 mL of 0.01 mol / L sodium hydroxide solution, heat and stir at 30 °C and 50 r / min for 0.1 h until the solid is completely dissolved, then add 0.01 mol / L sulfuric acid solution to the solution at a rate of 0.1 mL / min until pH = 1, heat and stir at 30 °C and 50 r / min for 0.1 h until precipitation stops, and prepare SA-TCPP dispersion;

[0095] (2) Disperse graphite oxide powder in ultrapure water and sonicate it (200W, 10kHz) for 0.1h to prepare a 0.01mg / mL GO dispersion.

[0096] (3) Add 10 mL of GO dispersion prepared in step (2) and 0.1 mL of 0.01 mg / mL glucose solution to the SA-TCPP dispersion prepared in step (1), sonicate (200 W, 10 kHz) for 0.1 h, heat and stir at 30 °C and 50 r / min for 0.1 h, centrifuge (1000 r / min) to collect the precipitate after the reaction is completed, wash the precipitate several times with ultrapure water, freeze dry at 0 °C for 1 h, and finally grind by hand for 0.1 h. The obtained product is recorded as 0.1% rGO / SA-TCPP photocatalyst.

[0097] (4) Add 15 mg of 0.1% rGO / SA-TCPP photocatalyst to the wastewater to be treated, disperse it by ultrasound (200W, 10kHz) for 0.1h, adjust the pH of the reaction system to 1 and the temperature to 0℃, stir at 50r / min for 0.1h to reach adsorption-desorption equilibrium, add 0.075 mg of ferric nitrate to the reaction system (the mass ratio of 0.1% rGO / SA-TCPP photocatalyst to Fe salt is 200:1), and then place the reaction system under a xenon lamp for irradiation to initiate the photocatalytic self-Fenton reaction based on 0.1% rGO / SA-TCPP. During the reaction, continuously introduce air (0.1 mL / min) to keep the solution in an oxygen-saturated state.

[0098] Example 9

[0099] A photocatalytic self-Fenton water treatment method based on rGO / SA-TCPP includes the following steps:

[0100] (1) Disperse 100 mg of tetra(4-carboxyphenyl)porphyrin powder in 1000 mL of 10 mol / L sodium carbonate solution, heat and stir at 100 °C and 1500 r / min for 10 h until the solid is completely dissolved, then add 10 mol / L nitric acid solution to the solution at 100 mL / min until pH = 10, heat and stir at 100 °C and 1500 r / min for 10 h until precipitation stops, and prepare SA-TCPP dispersion;

[0101] (2) Disperse graphene oxide powder in ultrapure water and sonicate it (800W, 50kHz) for 10h to prepare a GO dispersion of 100mg / mL.

[0102] (3) Add 10 mL of GO dispersion and 100 mL of 100 mg / mL sodium citrate solution to the SA-TCPP dispersion obtained in step (1), sonicate (800 W, 50 kHz) for 10 h, heat and stir at 100 °C and 1500 r / min for 10 h, centrifuge (15000 r / min) to collect the precipitate after the reaction, wash the precipitate several times with ultrapure water, dry at 100 °C and normal pressure for 50 h, and finally grind by hand for 10 h. The obtained product is recorded as 1000% rGO / SA-TCPP photocatalyst.

[0103] (4) Add 15 mg of 1000% rGO / SA-TCPP photocatalyst to the wastewater to be treated, disperse it by ultrasound (800W, 50kHz) for 10 h, adjust the pH of the reaction system to 14 and the temperature to 100℃, stir at 1500 r / min for 10 h to reach adsorption-desorption equilibrium, add 300 mg of ferric sulfate to the reaction system (the mass ratio of 1000% rGO / SA-TCPP photocatalyst to Fe salt is 1:20), and then place the reaction system under a high-pressure mercury lamp for irradiation to initiate the photocatalytic self-Fenton reaction based on 1000% rGO / SA-TCPP. During the reaction, continuously introduce oxygen-argon mixed gas (10 mL / min) to keep the solution in an oxygen-saturated state.

[0104] Comparative Example 1

[0105] The supramolecular self-assembly method for preparing SA-TCPP photocatalysts includes the following steps:

[0106] 100 mg of tetra(4-carboxyphenyl)porphyrin powder was dispersed in 71.43 mL of 0.05 mol / L potassium hydroxide solution. The solution was heated and stirred at 50 °C and 500 r / min for 0.5 h until the solid was completely dissolved. Then, 0.05 mol / L hydrochloric acid solution was added to the solution at a rate of 1 mL / min until the pH = 7. The solution was heated and stirred at 50 °C and 500 r / min for 1 h until precipitation stopped. After the reaction was completed, the precipitate was collected by centrifugation (8000 r / min), washed several times with ultrapure water, and dried under vacuum at 60 °C for 12 h. The product obtained was the SA-TCPP photocatalyst.

[0107] Comparative Example 2

[0108] The preparation of rGO by hydrothermal reduction includes the following steps:

[0109] 100 mg of graphite oxide powder was dispersed in ultrapure water and sonicated (560 W, 40 kHz) for 2 h to prepare a 1 mg / mL GO dispersion. Then, 100 mL of 1 mg / mL ascorbic acid solution was added and sonicated (560 W, 40 kHz) for 1 h. The mixture was then heated and stirred at 80 °C and 500 r / min for 4 h. After the reaction was completed, the precipitate was collected by centrifugation (8000 r / min), washed several times with ultrapure water, and dried under vacuum at 60 °C for 24 h. The resulting product was rGO.

[0110] Comparative Example 3

[0111] The preparation of g-C3N4 photocatalysts via high-temperature polycondensation includes the following steps:

[0112] Weigh 10g of melamine and transfer it to a 50mL covered crucible. Heat the crucible to 550℃ in a muffle furnace at a heating rate of 2℃ / min. Calcinate the product at 550℃ for 4 hours. After the calcined product cools naturally, grind it by hand for 1 hour. The resulting product is g-C3N4 photocatalyst.

[0113] Comparative Example 4

[0114] The preparation of 3% rGO / SA-TCPP by physical mixing includes the following steps:

[0115] 14.55 mg SA-TCPP and 0.55 mg rGO were manually ground and mixed for 1 hour. The resulting product was denoted as 3% rGO / SA-TCPP (physical mixture).

[0116] Comparative Example 5

[0117] A photocatalytic self-Fenton water treatment method based on SA-TCPP includes the following steps:

[0118] (1) Disperse 100 mg of tetra(4-carboxyphenyl)porphyrin powder in 71.43 mL of 0.05 mol / L potassium hydroxide solution, heat and stir at 50 °C and 500 r / min for 0.5 h until the solid is completely dissolved, then add 0.05 mol / L hydrochloric acid solution to the solution at 1 mL / min until pH = 7, heat and stir at 50 °C and 500 r / min for 1 h until precipitation stops, centrifuge (8000 r / min) to collect the precipitate after the reaction is completed, wash the precipitate several times with ultrapure water, and vacuum dry at 60 °C for 12 h. The product obtained is SA-TCPP photocatalyst.

[0119] (2) Add 15 mg of SA-TCPP photocatalyst to the wastewater to be treated, disperse it by ultrasonication (560 W, 40 kHz) for 0.5 h, adjust the pH of the reaction system to 6 and the temperature to 60 °C, stir at 500 r / min for 1 h to reach adsorption-desorption equilibrium, add 4 mg of ferric chloride (the mass ratio of SA-TCPP photocatalyst to Fe salt is 15:4) to the reaction system, and then place the reaction system under an LED lamp for irradiation to initiate the SA-TCPP-based photocatalytic self-Fenton reaction. During the reaction, oxygen is continuously introduced (1 mL / min) to keep the solution in an oxygen-saturated state.

[0120] Comparative Example 6

[0121] The Fenton water treatment method includes the following steps:

[0122] Add 4 mg of ferrous chloride to the wastewater to be treated and stir at 500 r / min for 0.5 h. Add H2O2 to the reaction system to make its concentration 82.7 μmol / L to initiate the Fenton reaction.

[0123] Example 10 Antibiotic Degradation Performance Test

[0124] Sulfamethoxypyrimidine (SDM) and sulfadiazine (SDZ) were selected as target degradation products. The degradation of SDM (50 mL, 10 ppm) or SDZ (50 mL, 10 ppm) was conducted using a Polyfibrillated PCX50C multichannel reactor. Visible light was emitted from a 10W LED lamp (100 mW / cm²). 2 Provided, the reaction system was adjusted to pH=6 and temperature=60℃. In the photocatalytic reaction system, the photocatalyst concentration was 0.3 g / L; in the photocatalytic self-Fenton reaction system, the photocatalyst concentration was 0.3 g / L, Fe... 3+ The salt concentration is 0.08 g / L; in the Fenton reaction system, Fe... 2+ The salt concentration was 0.08 g / L, and the H2O2 concentration was 82.7 μmol / L. After the degradation reaction started, 2 mL of the reaction solution was taken at regular intervals, centrifuged (11000 r / min) to remove the photocatalyst, and the supernatant was filtered through a 0.22 μm Millipore filter. The concentrations of SDM and SDZ in the supernatant were detected at 270 nm using high-performance liquid chromatography (Waters 1525) at a flow rate of 1 mL / min (Waters-C18, acetonitrile to 0.1% acetic acid aqueous solution volume ratio of 40:60). The TOC content in the supernatant was detected using a total organic carbon analyzer (Shimadzu, TOC-V CPH).

[0125] Figure 1The graph shows a comparison of the photocatalytic degradation performance of SDM under visible light between rGO / SA-TCPP prepared in Examples 1-6 and SA-TCPP prepared in Comparative Example 1. Figure 1 (a) It can be seen that the SA-TCPP, g-C3N4, and 3% rGO / SA-TCPP (physical mixture) samples exhibited low photocatalytic degradation activity, degrading only approximately 20.2%, 16.7%, and 17.9% of SDM, respectively, within 6 hours. In contrast, all rGO / SA-TCPP composite photocatalysts showed high degradation activity. As the rGO content increased from 0.5% to 5%, the photocatalytic degradation activity of the rGO / SA-TCPP composite material first increased and then decreased, with 3% rGO / SA-TCPP showing the highest SDM degradation activity and a degradation rate of 42.2%. Figure 1 (b) It can be seen that, through fitting the pseudo-first-order kinetic equation, the apparent rate constant (k) is obtained, and the k value of 3%rGO / SA-TCPP is the largest (0.093h). -1 ), respectively approximately SA-TCPP(0.036h -1 ), g-C3N4 (0.022h -1 ) and 3% rGO / SA-TCPP (physical mixture) (0.027h -1 The photocatalytic activity of 3% rGO / SA-TCPP was 2.6 times, 4.2 times, and 3.4 times that of SA-TCPP. Since the 3% rGO / SA-TCPP (physical mixture) was prepared by manual grinding, there was no close interaction between rGO and SA-TCPP. Therefore, rGO could not effectively enhance the light absorption capacity of the composite material, increase the number of surface active sites, or accelerate the separation and migration rate of photogenerated charges. Consequently, the photocatalytic activity of 3% rGO / SA-TCPP (physical mixture) was much lower than that of 3% rGO / SA-TCPP. When the rGO content was too low, the dispersion of SA-TCPP nanocrystals on the surface of the rGO nanosheets was not uniform enough, and the number of rGO as electron acceptors was limited, resulting in insufficient surface active sites and low migration rate of photogenerated charges, thus leading to a lack of significant improvement in the catalytic activity of the composite material. Conversely, when the rGO content was too high, the proportion of SA-TCPP decreased accordingly, resulting in fewer photogenerated carriers and longer migration distances of photogenerated electrons, thus affecting the improvement in the catalytic activity of the composite material. The above results demonstrate that combining SA-TCPP and rGO can indeed improve the photocatalytic degradation activity of the composite material, and the improved photocatalyst performance is a result of the synergistic effect of SA-TCPP and rGO. This proves that rGO / SA-TCPP exhibits superior photocatalytic degradation performance of organic matter compared to the SA-TCPP photocatalyst.

[0126] Example 11 Performance Test of H2O2 Synthesis

[0127] The synthesis of H2O2 was carried out using a PCX50C multichannel reactor from Profilo. Visible light was emitted from a 10W LED lamp (100mW / cm²). 2 The following steps are provided: First, add 15 mg of photocatalyst to 50 mL of SDM solution (10 ppm), ultrasonically disperse for 0.5 h, adjust the pH of the reaction system to 6, and the temperature to 25 °C or 60 °C. Stir continuously in the dark for 1 h. After turning on the light, take 1 mL of the reaction solution at regular intervals, add 3 mL of ultrapure water, centrifuge (11000 r / min) to remove the photocatalyst from the reaction solution, and filter the supernatant with a 0.22 μm Millipore filter. During the reaction, continuously introduce oxygen (1 mL / min) to keep the solution oxygen saturated. The content of H2O2 synthesized by photocatalysis was analyzed by iodometric titration: 1 mL of potassium hydrogen phthalate aqueous solution (0.1 mol / L) and 1 mL of potassium iodide aqueous solution (0.4 mol / L) were added to the supernatant, and the mixture was shaken on a shaker for 1 h. Then, the absorbance of the reaction solution at 350 nm was measured by a UV-Vis spectrophotometer (ShimadzuUV-3600Plus). The concentration of H2O2 produced at different reaction stages was calculated based on the H2O2 concentration-absorbance standard curve.

[0128] Figure 2 A comparison of the performance of 3% rGO / SA-TCPP prepared in Example 1 and SA-TCPP prepared in Comparative Example 1 in synthesizing H2O2 under visible light. Figure 2 It can be seen that after 6 hours of visible light irradiation at room temperature (25℃), the yield of H2O2 synthesized by SA-TCPP and the 3% rGO / SA-TCPP composite material was 2.1 mmol L. -1 g -1 and 2.4 mmol L -1 g -1 When the temperature rises to 60℃, the amount of H2O2 produced increases significantly. The cumulative concentration of H2O2 produced by SA-TCPP and 3% rGO / SA-TCPP after 6 hours of visible light irradiation can reach 3.2 mmol / L. -1 g -1 and 5.5 mmol L -1 g -1Compared to SA-TCPP, the 3% rGO / SA-TCPP sample exhibited enhanced activity under both room temperature (25℃) and heated (60℃) conditions, being 1.1 times and 1.7 times more active than SA-TCPP, respectively. Simultaneously, at 60℃, the yield of H2O2 synthesized by 3% rGO / SA-TCPP was 2.3 times that at room temperature (25℃). When the temperature rose to 60℃, the cumulative concentration of H2O2 synthesized by both SA-TCPP and 3% rGO / SA-TCPP photocatalytically increased significantly. This is because photogenerated electrons generated by SA-TCPP under light irradiation reduce O2 adsorbed on the -NH group of the pyrrole ring to generate H2O2, while photogenerated holes oxidize the carboxylic acid group in the SA-TCPP structure to a thermally unstable peroxycarboxylic acid intermediate. Further increasing the reaction temperature hydrolyzes the peroxycarboxylic acid intermediate to generate H2O2. The introduction of rGO can effectively enhance the light absorption capacity of the composite material, increase the number of surface active sites, and accelerate the separation and migration rate of photogenerated charges. This, in turn, improves the ability of rGO / SA-TCPP to synthesize H2O2 in situ via two reaction pathways: photogenerated electron reduction of O2 and photogenerated hole oxidation of carboxylic acid groups in the SA-TCPP structure. This demonstrates that the rGO / SA-TCPP photocatalyst exhibits superior H2O2 synthesis performance compared to the SA-TCPP photocatalyst.

[0129] Figure 3 The graph shows the cyclic synthesis performance of H2O2 from 3% rGO / SA-TCPP prepared in Example 1. Figure 3 It can be seen that after 4 cycles, the H2O2 activity synthesized by 3% rGO / SA-TCPP did not decrease significantly, indicating that it has good stability.

[0130] Figure 4 This is a comparison of the SDM degradation performance under different conditions using the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP prepared in Example 1. Figure 4 (a) It can be seen that the addition of Fe 3+ The salt reaction system has the best effect on the degradation of SDM, 3% rGO / SA-TCPP+Fe 3+ The degradation rate of SDM reached 94.5% within 6 hours of light exposure, while the degradation rates of 3% rGO / SA-TCPP and 3% rGO / SA-TCPP+Fe were significantly higher. 2+ The degradation rates were only 43.6% and 61.0%, which may be attributed to Fe. 3+ Reduced to Fe 2+ This process consumes a large number of photogenerated electrons, inhibiting electron-hole recombination and thus facilitating the release of more holes to participate in the oxidation reaction, thereby increasing the degradation performance of the reaction system for organic matter. Figure 4(b) It can be seen that the catalyst and Fe 3+ The reaction system exhibited the best SDM degradation effect when the salt mass ratio was 15:4. As the mass ratio increased from 15:2 to 15:4, the degradation activity significantly improved, and the degradation performance increased with increasing Fe content. 3+ The increase in salt content significantly improved H₂O₂ utilization; however, when the mass ratio increased to 15:6, the reaction system was affected by the reduced light transmittance of the solution, resulting in a slight weakening of degradation performance. Figure 4 (c) It can be seen that the reaction system at pH=6 has the best SDM degradation effect. When pH=6.0, the SDM degradation rate reaches 94.5% after 6 hours of illumination, which is much higher than the degradation rates at pH=2.0 (48.4%) and pH=9.0 (78.6%). Therefore, the photocatalytic self-Fenton reaction system is selected with added Fe 3+ Salt, catalyst and Fe 3+ The experiment was conducted under conditions of a salt mass ratio of 15:4 and pH = 6.

[0131] Figure 5 This is a comparison chart showing the SDM degradation and TOC removal rates of the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP-PSF in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP-PSF in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6. Figure 5 As shown in (a) and 5(b), the Fenton system exhibits poor degradation performance of SDM, while the 3% rGO / SA-TCPP photocatalytic system can degrade approximately 63.0% of SDM within 6 hours, with a k value of 0.17h. -1 It is the SA-TCPP photocatalytic system (0.07h) -1 2.4 times that of ); plus Fe 3+ Subsequently, the degradation activities of the photocatalytic self-Fenton system based on SA-TCPP and 3% rGO / SA-TCPP were significantly improved. The photocatalytic self-Fenton system based on 3% rGO / SA-TCPP degraded approximately 94.5% of SDM within 6 hours, with a k-value as high as 0.53 h. -1 The results were based on a 3% rGO / SA-TCPP photocatalytic system (0.17h). -1 It is 3.1 times that of the SA-TCPP-based photocatalytic system (0.07h). -1 It is 7.6 times that of the SA-TCPP photocatalytic self-Fenton system (0.09h). -1 It is 5.9 times that of the Fenton system (0.03h) and is also 5.9 times that of the Fenton system (0.03h). -117.7 times that of ) . TOC can be used to analyze and evaluate the ability of water treatment technologies to remove mineralized antibiotics, by Figure 5 (c) It can be seen that after 8 hours of reaction, the TOC removal rate of the 3% rGO / SA-TCPP photocatalytic system reached 41.8%, which is 4.2 times that of the SA-TCPP photocatalytic system (9.9%), indicating that 3% rGO / SA-TCPP has a higher mineralization capacity under visible light. It is worth noting that the TOC removal rate of the photocatalytic self-Fenton system is significantly higher than that of the photocatalytic system. After 8 hours of reaction, the TOC removal rate of the 3% rGO / SA-TCPP photocatalytic self-Fenton system for SDM was 61.9%, which is 1.5 times that of the 3% rGO / SA-TCPP photocatalytic system (41.8%), 6.3 times that of the SA-TCPP photocatalytic system (9.9%), 2.1 times that of the SA-TCPP photocatalytic self-Fenton system (28.9%), and 13.2 times that of the Fenton system (4.7%). This is mainly because, compared to photocatalytic water treatment methods, the 3% rGO / SA-TCPP-based photocatalytic self-Fenton water treatment method generates more ·OH and photogenerated holes, further enhancing its oxidation capacity and mineralization efficiency; compared to Fenton water treatment methods, the Fe in the 3% rGO / SA-TCPP-based photocatalytic self-Fenton water treatment method is higher. 3+ It can be promptly reduced to Fe by photogenerated electrons. 2+ Promote Fe 3+ / Fe 2+ The cyclic transformation significantly increases the in-situ production of H2O2 and Fe by 3% rGO / SA-TCPP. 2 + The efficiency of generating ·OH through the self-Fenton reaction further enhances the oxidation capacity of the reaction system. This demonstrates that the 3% rGO / SA-TCPP photocatalyst exhibits superior organic matter degradation performance and mineralization efficiency compared to the SA-TCPP photocatalyst. Furthermore, it demonstrates that the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP possesses superior organic matter degradation performance and mineralization efficiency compared to photocatalysis alone and Fenton water treatment methods.

[0132] Figure 6This is a comparison of the degradation of SDZ using the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP-PSF in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP-PSF in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6; where (a) is the degradation activity curve and (b) is the apparent rate constant. Figure 6 As shown in (a) and 6(b), the Fenton system exhibits poor degradation performance of SDZ, while the 3% rGO / SA-TCPP photocatalytic system degrades approximately 57.9% of SDZ within 6 hours, with a k-value of 0.140 h. -1 It is the SA-TCPP photocatalytic system (0.056h) -1 The degradation activity was 2.5 times that of the standard photocatalytic system; compared to the standard photocatalytic system, the SA-TCPP-based and 3% rGO / SA-TCPP-based photocatalytic self-Fenton systems exhibited higher SDZ degradation activity; the 3% rGO / SA-TCPP-based photocatalytic self-Fenton system degraded approximately 86.7% of SDZ within 6 hours, with a k-value of 0.318h. -1 The two are photocatalytic systems based on SA-TCPP (0.056h). -1 The efficiency of the photocatalytic self-Fenton system based on SA-TCPP is 5.7 times that of the previous system (0.130h). -1 2.4 times that of ) based on a 3% rGO / SA-TCPP photocatalytic system (0.140h) -1 2.3 times that of the Fenton system (0.0140h) -1 The above results indicate that the 3% rGO / SA-TCPP photocatalytic self-Fenton system has good universality in removing antibiotic-like organic matter. This is mainly attributed to the synergistic effect of the introduction of rGO and the photocatalytic self-Fenton, which can significantly improve the degradation capacity and mineralization efficiency of the reaction system for organic matter, and therefore has great potential in water environment purification.

[0133] Figure 7 This is a cyclic degradation activity diagram of the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7. Figure 7 It can be seen that after four consecutive cycles of degradation, the activity of the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP for degrading SDM did not decrease significantly, indicating that it has good stability.

[0134] Example 12 Test of performance in killing drug-resistant bacteria

[0135] Sulfonamide ARBs were selected as the target bacterial strain, and antibacterial experiments were conducted using a Polyfibrillated PCX50C multichannel reactor. Visible light was provided by a 10W LED lamp (100mW / cm²). 2 The reaction system was adjusted to pH 6 and temperature 37℃. In the photocatalytic reaction system, the photocatalyst concentration was 0.3 g / L; in the photocatalytic self-Fenton reaction system, the photocatalyst concentration was 0.3 g / L, Fe... 3+ The salt concentration is 0.08 g / L; in the Fenton reaction system, Fe... 2+ The salt concentration was 0.08 g / L, and the H2O2 concentration was 82.7 μmol / L. Sulfonamide ARBs were incubated in Luria Bertani (LB) liquid medium at 37°C with shaking for 5 h. Bacterial cells were collected by centrifugation (4000 r / min, 5 min), washed several times with sterile physiological saline, and then resuspended in physiological saline solution. The concentration of sulfonamide ARBs in the antibacterial experiment was approximately 1 × 10⁻⁶ g / L. 7 cfu / mL. After the antibacterial reaction begins, equal amounts of bacterial suspension are taken at regular time intervals, diluted with sterile physiological saline, and 0.1 mL of the diluted solution is spread on LB solid medium and incubated at 37°C for 12 h. The number of bacteria in the bacterial suspension is counted using the plate count method. Each experiment is performed in triplicate. The experimental apparatus and physiological saline solution are sterilized at 121°C for 20 min.

[0136] Figure 8 This is a comparison chart showing the performance of the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP-PSF in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP-PSF in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6 in killing sulfonamide ARBs. Figure 8It was found that the light-controlled group (without photocatalyst but with visible light irradiation), the dark-controlled group (with photocatalyst but without visible light irradiation), and the Fenton system all showed poor removal effects on sulfonamide ARBs. The SA-TCPP-based photocatalytic system achieved a removal rate of 42.8% for sulfonamide ARBs within 4 hours, while the 3% rGO / SA-TCPP-based photocatalytic system achieved a removal rate of 91.7% within 4 hours. This is attributed to the fact that the introduction of rGO can enhance the light absorption capacity of the material, promote the migration of photogenerated charges, and expose more reactive sites, thereby improving the antibacterial performance of 3% rGO / SA-TCPP. Meanwhile, the sterilization effect of the SA-TCPP-based and 3% rGO / SA-TCPP-based photocatalytic self-Fenton systems on sulfonamide ARBs was significantly higher than that of the photocatalytic system. The SA-TCPP-based photocatalytic self-Fenton system achieved a removal rate of 59.9% for sulfonamide ARBs at 4 hours, which was higher than the removal rate of the SA-TCPP-based photocatalytic system (42.8%). The 3% rGO / SA-TCPP-based photocatalytic self-Fenton system showed the best sterilization performance, with removal rates of 97.1% and 100.0% for sulfonamide ARBs at 3 hours and 4 hours, respectively, which were much higher than the removal rates of the 3% rGO / SA-TCPP-based photocatalytic system (65.6% and 91.7%). Notably, the photocatalytic self-Fenton system based on 3% rGO / SA-TCPP achieved a 100.0% removal rate of sulfonamide ARBs within 4 hours, while the SA-TCPP-based photocatalytic self-Fenton system only achieved a 40.1% removal rate within 4 hours. This indicates that the introduction of rGO and the synergistic effect of photocatalytic self-Fenton are equally important in improving ARB removal performance. This demonstrates that the 3% rGO / SA-TCPP photocatalyst exhibits superior antibacterial properties compared to the SA-TCPP photocatalyst. Furthermore, it demonstrates that the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP possesses superior antibacterial properties compared to photocatalysis and Fenton water treatment methods alone.

[0137] Example 13 Performance test for removing resistance genes

[0138] Using sulfonamide ARGs(sul1) as the target resistance gene, 200 mL of environmental water sample containing sulfonamide ARGs(sul1) was treated. The experiment was conducted using a Polyfiber PCX50C multichannel reactor, with visible light provided by a 10W LED lamp (100mW / cm²). 2 The reaction system was adjusted to pH 6 and temperature 37℃. In the photocatalytic reaction system, the photocatalyst concentration was 0.25 g / L; in the photocatalytic self-Fenton reaction system, the photocatalyst concentration was 0.25 g / L, Fe... 3+ The salt concentration is 0.07 g / L; in the Fenton reaction system, Fe... 2+The salt concentration was 0.07 g / L, and the H2O2 concentration was 82.7 μmol / L. The reaction to remove resistance genes was carried out under stirring conditions for 4 h. After the reaction, the water sample was filtered, and the filter membrane was cut into pieces. DNA was extracted using a soil genomic DNA extraction kit. The concentration of DNA in the sample was detected using a Nanodrop micro spectrophotometer. The absolute abundance of sulfonamide ARGs (sul1) in the sample was detected using a real-time quantitative PCR (qPCR) analyzer (StepOnePlus, ABI). Each experiment was performed in triplicate.

[0139] Figure 9 This is a comparison chart showing the performance of the photocatalytic water treatment method based on 3% rGO / SA-TCPP prepared in Example 1, the photocatalytic water treatment method based on SA-TCPP prepared in Comparative Example 1, the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP in Example 7, the photocatalytic self-Fenton water treatment method based on SA-TCPP in Comparative Example 5, and the Fenton water treatment method in Comparative Example 6 in removing sulfonamide ARGs. Figure 9 It was found that after 4 hours of reaction, the removal rate of sulfonamide ARGs (sul1) in the water sample based on the 3% rGO / SA-TCPP photocatalytic system reached 74.8%, which was 2.9 times that of the SA-TCPP-based photocatalytic system (25.9%). This is attributed to the fact that the introduction of rGO enhanced the light absorption capacity of the material, promoted the migration of photogenerated charges, and exposed more active sites, thereby improving the performance of 3% rGO / SA-TCPP in removing ARGs. Compared with the photocatalytic system, the removal efficiency of sulfonamide ARGs (sul1) by the SA-TCPP and 3% rGO / SA-TCPP photocatalytic self-Fenton system was significantly improved. Under the same conditions, the 3% GO / SA-TCPP photocatalytic self-Fenton system achieved the best removal rate of sulfonamide ARGs (sulfuric acid precipitates) in the water sample, reaching 99.6%. This is 3.8 times the removal rate of the SA-TCPP photocatalytic system (25.9%), 1.7 times the removal rate of the SA-TCPP photocatalytic self-Fenton system (57.2%), 1.3 times the removal rate of the 3% GO / SA-TCPP photocatalytic system (74.8%), and 10.0 times the removal rate of the Fenton system (9.9%). In summary, the synergistic effect of introducing rGO and the photocatalytic self-Fenton system can further enhance the oxidation capacity of the SA-TCPP reaction system, thereby improving the performance of ARG removal. This demonstrates that the 3% rGO / SA-TCPP photocatalyst has superior performance in removing ARGs compared to the SA-TCPP photocatalyst. Meanwhile, it was demonstrated that the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP has superior performance in removing sulfonamide ARGs compared to photocatalysis alone and Fenton water treatment methods.

[0140] Transmission electron microscope (TEM) images were captured using a transmission electron microscope (JEOL JEM-2100) with an electron beam acceleration voltage of 200 kV. Figure 10 TEM comparison images of the 3% rGO / SA-TCPP prepared in Example 1, SA-TCPP prepared in Comparative Example 1, and rGO prepared in Comparative Example 2. Figure 10 (a) shows that rGO exhibits a two-dimensional nanosheet morphology. From Figure 10 (b) It can be seen that SA-TCPP exhibits a small-sized nanocrystalline structure with a diameter of 10–20 nm. Figure 10 (c) It can be seen that after SA-TCPP is combined with rGO, the SA-TCPP particles are uniformly dispersed on the rGO nanosheets. This heterogeneous structure of 3% rGO / SA-TCPP is beneficial to increasing the reactive sites.

[0141] The X-ray diffraction spectra (XRD) of the samples were studied using a Bruker D2-phaser X-ray diffractometer (CuKα, 30kV, 10mA). Figure 11 The images show a comparison of XRD patterns of the rGO / SA-TCPP prepared in Examples 1-6 with SA-TCPP prepared in Comparative Example 1 and rGO prepared in Comparative Example 2. Figure 11 It can be seen that the characteristic peaks of rGO at 16.8° and 25.4° correspond to the 001 and 002 diffraction peaks of the hexagonal graphite crystal structure, respectively; the broad diffraction peaks of SA-TCPP at 15-30° indicate that it has the characteristics of organic supramolecular π-π stacking and nanocrystalline structure; as the proportion of rGO in the composite material increases, the intensity of the broad diffraction peak corresponding to SA-TCPP at 15-30° in rGO / SA-TCPP gradually decreases, while the intensity of the 002 diffraction peak corresponding to rGO gradually increases, indicating that rGO and SA-TCPP are successfully combined.

[0142] The Fourier transform infrared (FTIR) spectra of the samples were studied using a Thermo Fisher Nicolet IS10 spectrometer. Figure 12 The image shows a comparison of FTIR spectra of rGO / SA-TCPP prepared in Examples 1-6 with SA-TCPP prepared in Comparative Example 1 and rGO prepared in Comparative Example 2. Figure 12 It can be seen that rGO is at 3454cm -1 The peak at 1599 cm⁻¹ corresponds to the OH stretching vibration. -1 The peak at 1064 cm⁻¹ corresponds to the C=C stretching vibration of the aromatic ring. -1 and 1166cm -1 The peak at 966 cm⁻¹ corresponds to the CO stretching vibration. SA-TCPP occurs at 966 cm⁻¹. -1 and 784cm-1 The absorption peaks correspond to the NH bending vibration and the out-of-plane bending vibration of CH in the benzene ring, respectively, at 3303 cm⁻¹. -1 1606cm -1 and 1400cm -1 The absorption peaks at 3450 cm⁻¹ correspond to the stretching vibrations of the NH, C=C, and CN groups of the pyrrole ring, respectively. -1 1696cm -1 and 1181cm -1 The peaks correspond to the stretching vibrations of the OH, CO, and C=O groups of the carboxyl group surrounding the porphyrin ring, respectively. Compared with SA-TCPP, as the rGO ratio increases, the peaks corresponding to OH (~3450 cm⁻¹) increase. -1 ) and C = C (~1600cm) -1 The stretching vibration peaks of SA-TCPP gradually shift to lower wavenumbers, indicating that there are hydrogen bonds and π-π interactions between SA-TCPP and rGO.

[0143] The Raman spectra of the samples were measured using a microconfocal Raman spectrometer (Thermofisher DXR2xi) with an excitation wavelength of 532 nm. Figure 13 Raman comparison images of the 3% rGO / SA-TCPP prepared in Example 1, SA-TCPP prepared in Comparative Example 1, and rGO prepared in Comparative Example 2. Figure 13 It can be seen that rGO is at 1329cm -1 and 1562cm -1 The peak at that point corresponds to the D-band and G-band, with the G-band consisting of sp. 2 The D band is generated by the vibration of carbon atoms, and consists of sp bands from disordered carbon or defective graphite structures. 3 The vibrations of carbon atoms produce the signal; SA-TCPP does not exhibit obvious Raman characteristic peaks, indicating that the electron cloud of the 18-π-electron aromatic structure in SA-TCPP is relatively stable; the D band of 3% rGO / SA-TCPP shifts to 1367 cm⁻¹. -1 The G-band moved to 1592cm -1 The shifts in these Raman peaks are primarily due to the π-π interaction between rGO and SA-TCPP; the ratio of the G-band to the D-band peak intensities (Ig) is typically used. G / I D To evaluate the π-π packing degree of the material, the I of 3% rGO / SA-TCPP G / I D The value (1.2) is higher than that of rGO (0.8), indicating that after rGO and SA-TCPP are combined, the similar conjugated π structure of the two enhances the degree of ordered π-π packing of the composite material, which in turn helps to enhance the π electron delocalization effect and electronic coupling effect, and promotes the migration of photogenerated carriers in the 3% rGO / SA-TCPP reaction system.

[0144] The diffuse reflectance (DRS) spectrum of the sample was measured using a UV-Vis spectrophotometer (Shimadzu UV-3600Plus). Figure 14 The image shows a comparison of the DRS values ​​of the 3% rGO / SA-TCPP prepared in Example 1, the SA-TCPP prepared in Comparative Example 1, and the rGO prepared in Comparative Example 2. Figure 14 It can be seen that the spectral response range of SA-TCPP spans the entire visible light region, with the strong absorption peak at 350-380 nm corresponding to the Soret (B) band, and the weak absorption peak at 500-700 nm corresponding to the Q band; the peak of rGO at 210 nm corresponds to the sp band. 2 The π-π* transition characteristic peaks on the basal plane (C=C) are observed. After SA-TCPP and rGO are combined, 3% rGO / SA-TCPP exhibits stronger light absorption and a wider light absorption range than SA-TCPP, with the absorption edge extending from the visible light region to the near-infrared region. Furthermore, compared to SA-TCPP and rGO alone, the absorption peaks of the Soret (B) band and Q band of 3% rGO / SA-TCPP show enhanced intensity and redshifted positions, while the π-π* transition characteristic peaks also exhibit a slight redshift, further illustrating the π-π interaction between SA-TCPP and rGO. The stronger light absorption intensity and wider spectral response range of 3% rGO / SA-TCPP can effectively improve the material's utilization of sunlight, thereby generating a greater number of photogenerated carriers to participate in the reaction.

[0145] Example 14 Photoelectric conversion performance test

[0146] Photoelectric conversion performance was tested on a CHI 660D electrochemical workstation (Chenhua Instrument). The standard three-electrode system included a counter electrode (platinum wire), a reference electrode (saturated calomel electrode), and a working electrode, with 0.1 mol / L Na₂SO₄ solution used as the electrolyte. The working electrode was prepared as follows: 5 mg of sample powder was ultrasonically dispersed in 1 mL of ultrapure water. The suspension was coated onto an indium tin oxide (ITO) glass surface, dried at room temperature, and heated at 180 °C for 5 h. A 300 W xenon lamp with a 400 nm cutoff filter was used as the visible light source. Photocurrent response was measured at 0.0 V; electrochemical impedance spectroscopy (EIS) was performed at 5 mV AC voltage from 0.01 Hz to 10 Hz. 5 Recorded within the Hz range.

[0147] Figure 15 This is a comparison of the photoelectric conversion performance of the 3% rGO / SA-TCPP prepared in Example 1 and the SA-TCPP prepared in Comparative Example 1. Figure 15(a) It can be seen that, compared with SA-TCPP, 3% rGO / SA-TCPP has a stronger photocurrent response value, approximately 2.2 times that of SA-TCPP. This indicates that the separation efficiency of photogenerated charges generated by 3% rGO / SA-TCPP is significantly improved, allowing more photogenerated electrons to migrate from 3% rGO / SA-TCPP to the ITO glass substrate. Figure 15 (b) It can be seen that under both dark and light conditions, the radius of the arc of 3% rGO / SA-TCPP is smaller than that of SA-TCPP, indicating that its transfer resistance of photogenerated charge at the interface is lower, and the recombination probability of photogenerated electron-hole pairs is significantly suppressed. Compared with SA-TCPP, 3% rGO / SA-TCPP has a more outstanding photoelectric conversion capability. This is mainly because the introduction of highly conductive rGO improves the separation and migration efficiency of photogenerated electrons and holes in the composite material. At the same time, the π-π interaction between rGO and SA-TCPP enhances the electron delocalization effect, which can promote the migration of photogenerated electrons in SA-TCPP along the π-π stacking direction. Since the synthesis of H2O2 by 3% rGO / SA-TCPP requires two reaction pathways: the reduction of O2 by photogenerated electrons and the oxidation of the carboxylic acid group in the SA-TCPP structure by photogenerated holes to form a peroxycarboxylic acid intermediate followed by thermal decomposition, the performance of 3% rGO / SA-TCPP in synthesizing H2O2 is stronger. Since the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP requires the reduction of Fe by photogenerated electrons, the performance of 3% rGO / SA-TCPP in synthesizing H2O2 is stronger. 3+ The 3% rGO / SA-TCPP photocatalytic self-Fenton water treatment method achieves the removal of antibiotics, ARBs, and ARGs through photogenerated hole oxidation of pollutants. It demonstrates that compared to the SA-TCPP photocatalyst, the 3% rGO / SA-TCPP photocatalyst exhibits faster photogenerated carrier separation and migration rates, resulting in superior H2O2 synthesis and removal performance of antibiotics, ARBs, and ARGs, making it a better carrier for constructing a photocatalytic self-Fenton synergistic reaction system.

[0148] Figure 16 This is a comparison of the SDM degradation performance of the photocatalytic self-Fenton water treatment method (3% rGO / SA-TCPP-PSF) based on 3% rGO / SA-TCPP in Example 7 after the addition of different active species capture agents. Figure 16 It can be seen that ammonium oxalate (AO), isopropanol (IPA), p-benzoquinone (p-BQ), and furfuryl alcohol (FFA) are used to capture photogenerated h, respectively. + ·OH, ·O2 - and 1O2 and blank control group results showed that SDM had good stability under light irradiation. The addition of AO and IPA significantly inhibited the degradation rate of SDM by the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP, while the addition of p-BQ and FFA had relatively low inhibitory effects on degradation performance. The contribution of active species was, in descending order, h + >·OH>·O2 - > 1 O2, indicating h + O2 - ·OH and 1 O2 participated in the reaction, among which h + ·OH plays a crucial role in the reaction process of the photocatalytic self-Fenton water treatment method based on 3% rGO / SA-TCPP.

Claims

1. The application of a photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin in the removal of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics from water, characterized in that, The water treatment method is as follows: graphene / self-assembled tetra(4-carboxyphenyl)porphyrin photocatalyst is added to the wastewater to be treated, the pH and temperature of the reaction system are adjusted, Fe salt is added to the reaction system to construct a photocatalytic self-Fenton system, the reaction system is placed under a light source for irradiation, and continuous aeration is carried out to keep the solution in an oxygen-saturated state. The method for preparing the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin is as follows: Step 1: Tetra(4-carboxyphenyl)porphyrin is dispersed in an alkaline solution, heated and stirred until the solid is completely dissolved, an acid solution is added, the pH is adjusted, and the mixture is heated and stirred until precipitation stops, thus preparing a self-assembled tetra(4-carboxyphenyl)porphyrin dispersion, i.e., SA-TCPP dispersion; Step 2: GO dispersion is obtained by dispersing graphene oxide in water and sonicating; Step 3: SA-TCPP dispersion, GO dispersion, and reducing agent solution are mixed, sonicated, heated and stirred, and after the reaction is completed, separated, purified, dried, and ground to prepare graphene / self-assembled tetra(4-carboxyphenyl)porphyrin, i.e., rGO / SA-TCPP photocatalyst; the mass ratio of graphene oxide to self-assembled tetra(4-carboxyphenyl)porphyrin is 1:20~200; the mass ratio of rGO / SA-TCPP photocatalyst to Fe salt is 15:

4.

2. The application of the photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin as described in claim 1 in the removal of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics from water, characterized in that... The Fe salts mentioned include ferric chloride, ferrous chloride, ferric nitrate, ferrous nitrate, ferrous sulfate, or ferrous sulfate; The introduced gas includes oxygen, air, or an oxygen-argon mixture, and the gas flow rate is 0.1~10 mL / min; Light sources include LED lamps, xenon lamps, high-pressure mercury lamps, metal halide lamps, or sunlight.

3. The application of the photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin as described in claim 1 in the removal of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics from water, characterized in that... After adjusting the pH and temperature of the reaction system, stir to reach adsorption-desorption equilibrium. The stirring speed is 50~1500 r / min and the stirring time is 0.1~10 h.

4. The application of the photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin as described in claim 1 in the removal of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics from water, characterized in that... In step 1 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method: Acid solutions include hydrochloric acid, sulfuric acid, nitric acid, or acetic acid solutions.

5. The application of the photocatalytic self-Fenton water treatment method based on graphene / self-assembled tetra(4-carboxyphenyl)porphyrin as described in claim 1 in the removal of sulfonamide antibiotics, quinolone antibiotics, and tetracycline antibiotics from water, characterized in that... In step 3 of the graphene / self-assembled tetra(4-carboxyphenyl)porphyrin preparation method: the reducing agent includes ascorbic acid, glucose or sodium citrate, and the concentration of the reducing agent is 0.01~100 mg / mL.

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