A fenton-like oxidation membrane suitable for weak acid conditions and application thereof

Abstract

The application discloses a Fenton-like oxidation membrane suitable for weak acid conditions and application thereof, and a membrane reactor capable of realizing self-supply and self-catalysis of H2O2 is prepared by synthesizing bifunctional Pt / CuO2 JNPs and loading the Pt / CuO2 JNPs on the surface of a PVDF membrane. 2+ The functional unit CuO2 NPs can dissociate and output Cu 2+ / Cu + cycle and drive a Fenton-like oxidation system with H2O2 self-supply. On the other hand, the functional unit Pt NPs can further activate H2O2 to generate reactive oxygen species as a kind of high-efficiency nano-enzyme catalyst, so that the efficiency of the membrane reactor in catalytic degradation of antibiotics is improved. Meanwhile, the nano-confinement effect of the nanometer cavity existing in the membrane reaction surface is utilized in the degradation process, so that the interaction between antibiotic molecules and functional materials is enhanced, and the catalytic efficiency of the membrane reactor is improved. Therefore, the bifunctional Pt / CuO2 JNPs capable of self-supply and self-catalysis of H2O2 are loaded on the surface of a PVDF membrane, so that an "All-in-One" Fenton-like oxidation membrane reactor capable of being applied all day long under natural pH conditions is constructed. Meanwhile, the nanometer cavity existing on the surface of the PVDF membrane is utilized to improve the reaction efficiency of the membrane reactor in catalytic degradation of antibiotics by means of the nano-confinement effect.

Description

Technical Field

[0001] This invention belongs to the field of inorganic nanomaterials technology, specifically relating to a Fenton-like oxide film suitable for weakly acidic conditions and its applications. Background Technology

[0002] In recent years, antibiotics, as important antibacterial drugs, have been widely used in agriculture, animal husbandry, and human healthcare. However, the overuse of antibiotics and their bioaccumulation in food pose a significant threat to public health. Excessive antibiotic levels in the environment can induce increased bacterial resistance, leading to the development of resistance genes through gene transfer and mutation, ultimately resulting in drug-resistant strains that seriously threaten public health. Currently, technologies such as physical adsorption, biodegradation, photocatalysis, and advanced oxidation processes have been reported for the elimination and degradation of residual antibiotics in environmental media. Among these methods, physical adsorption is costly and cannot fundamentally remove antibiotics; biological degradation has low efficiency, and most antibiotics cannot be completely degraded; photocatalysis, which uses semiconductor materials to absorb light and generate reactive oxygen species to oxidize and degrade antibiotics, also suffers from low catalytic efficiency and is sensitive to the intensity of incident sunlight, limiting its efficiency at night or when sunlight is weak; while advanced oxidation technologies, such as the Fenton oxidation reaction, produce highly reactive hydroxyl radicals (·OH), giving the Fenton oxidation system high oxidation efficiency, but it has a low and narrow pH range and low Fe content. 2+ / Fe 3+ The low recycling efficiency of traditional Fenton oxidation systems leads to the generation of iron sludge, causing secondary pollution. Even more problematic is the fact that the low utilization efficiency of H2O2 in the reaction system necessitates the addition of excessive H2O2, which clearly contradicts the principles of sustainable development.

[0003] Therefore, developing a Fenton-like oxide membrane suitable for weakly acidic conditions and its application to promote the efficient degradation and elimination of residual antibiotics in environmental media is an urgent problem to be solved in the field of environmental analysis. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a Fenton-like oxide film suitable for weakly acidic conditions and its applications. This invention prepares a novel bifunctional Fenton-like oxidant, Pt / CuO2 JNPs, through hydrothermal and self-assembly reactions. On one hand, under weakly acidic conditions, the functional unit CuO2 NPs can dissociate and release Cu... 2+ With H2O2, the reaction system can achieve self-supply of H2O2, and a Cu-based system can also be constructed. 2+ / Cu +A Fenton-like oxidation system driven by a cycle. On the other hand, functional units Pt NPs, as highly efficient nanozyme catalysts, can further accelerate the decomposition of H2O2, accelerate molecular oxygen activation in the reaction system, and improve the efficiency of antibiotic degradation. Furthermore, another way to improve the degradation efficiency of organic pollutants is to enhance the interaction between organic molecules and active substances. Accordingly, this invention uses a PVDF membrane as a carrier and loads the prepared Pt / CuO2 JNPs onto its surface through vacuum filtration. During the degradation process, the nano-confinement effect of the cavities on the membrane reaction surface is utilized to enhance the interaction between antibiotic molecules and functional materials, thereby improving the catalytic efficiency of the membrane reactor.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] The first objective of this invention is to provide a Fenton-like oxidant, the preparation method of which includes the following steps:

[0007] (1) Synthesis of CuO2 NPs: (CuNO3)2·3H2O and polyvinylpyrrolidone were dissolved in ultrapure water, and NH3·H2O and H2O2 were added to the mixed solution in sequence. After stirring and centrifugation, the solution was washed multiple times with ultrapure water and ethanol solution to obtain CuO2 NPs.

[0008] (2) Synthesis of Pt NPs: H2PtCl6 and PVP were dissolved in deionized water to prepare Pt nano-dendritic crystals; then, ascorbic acid solution was added dropwise to the above H2PtCl6 solution, and after stirring at 45°C, a dispersion of Pt NPs was prepared.

[0009] (3) Synthesis of Pt / CuO2 JNPs: The CuO2 NPs prepared in step (1) were dispersed in a 6.7% ethanol aqueous solution and CTAB solution was added. The mixture was heated to 75°C and liquid paraffin was added. The mixture was stirred at 75°C for 1 h to form a Pickering emulsion. The mixture was cooled to room temperature and diluted with methanol. 3-mercaptopropyltrimethoxysilane was added to the emulsion to functionalize its surface. After stirring for 3 h, the resulting solid was centrifuged. After washing with methanol several times, the surface thiol-functionalized CuO2 NPs were redispersed in the Pt NPs dispersion prepared in step (2). The mixture was stirred at room temperature overnight. The resulting solid was centrifuged and filtered, washed with chloroform and dried to prepare Pt / CuO2 JNPs.

[0010] Preferably, in step (1), the molar ratio of (CuNO3)2·3H2O to polyvinylpyrrolidone is 1:0.01, the ratio of (CuNO3)2·3H2O to polyvinylpyrrolidone ultrapure water is 1:1, the volume ratio of NH3·H2O to H2O2 is 0.02:1, the stirring time is 30-60 min, and the CuO2NPs obtained in step (1) are stored in anhydrous ethanol at 4℃.

[0011] Preferably, in step (2), the molar ratio of H2PtCl6 to PVP is 1:0.5, the ratio of H2PtCl6 to ultrapure water of PVP is 1:10, the molar ratio of ascorbic acid to H2PtCl6 is 1:10, and the stirring time is 1-1.5h.

[0012] Preferably, in step (3), the molar ratio of CuO2 NPs to CTAB is 1000:1, the ratio of CuO2 NPs to CTAB in ultrapure water is 500:1, the volume ratio of CuO2 NPs to liquid paraffin is 10:1, the volume ratio of CuO2 NPs to methanol is 1:1, the volume ratio of CuO2 NPs to (3-mercaptopropyl)trimethoxysilane is 50:1, the stirring reaction time after adding liquid paraffin is 1-1.5 h, and the stirring reaction time after functionalization treatment is 3-5 h.

[0013] The second objective of this invention is to provide a Fenton-like oxide membrane. The preparation method of the Fenton-like oxide membrane includes the following steps: dispersing the prepared Fenton-like oxidant in deionized water, sonicating, and then loading Pt / CuO2 JNPs onto the surface of a PVDF membrane by vacuum filtration to obtain a membrane reactor.

[0014] Preferably, the ultrasonic time is 20-40 min, and the prepared membrane reactor is stored at 4°C.

[0015] A third objective of this invention is to provide an application of a Fenton-like oxide film in the environment for antibiotic degradation.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The system can initiate a highly efficient Fenton-like oxidation reaction under natural pH conditions. Compared with the traditional Fenton oxidation which requires strong acid conditions, this reaction system is more practical.

[0018] (2) The reactor has no requirements for natural environmental conditions and meets the requirements for all-weather applicability.

[0019] (3) The reactor can achieve self-supply and self-catalysis of H2O2 without the need to add other Fenton oxidizing agents, which is beneficial for on-site immediate application in the field of environmental remediation.

[0020] (4) Functional materials Pt / CuO2 JNPs can be used to construct Cu 2+ / Cu + The reaction mechanism of cyclic and Pt NPs synergistic activation of H2O2 accelerates molecular oxygen activation and improves the catalytic degradation efficiency of membrane reactors.

[0021] (5) By utilizing the nano-confinence effect of the cavity on the membrane reaction surface, the interaction between antibiotic molecules and functional materials is enhanced, thereby improving the catalytic efficiency of the membrane reactor. Attached Figure Description

[0022] Figure 1 This is a schematic diagram and a degradation mechanism diagram of the membrane reactor prepared in this invention for degrading antibiotics exposed to the aquatic environment;

[0023] Figure 2 A- Figure 2 C represents the TEM and HRTEM images of the CuO2 NPs prepared in this invention;

[0024] Figure 2 D- Figure 2 F is the TEM and HRTEM image of the Pt / CuO2 JNPs prepared in this invention;

[0025] Figure 3 A is an optical photograph of the PVDF membrane before and after functionalization with Pt / CuO2 JNPs, and of the prepared membrane reactor under bending and stretching conditions in this invention.

[0026] Figure 3 B is a planar and cross-sectional SEM image of the PVDF membrane and membrane reactor in this invention;

[0027] Figure 3 C is a comparison diagram of the contact angle between the PVDF membrane and the membrane reactor in this invention;

[0028] Figure 3 D represents the flow rate variation of membrane reactors with different Pt / CuO2 JNPs loadings under the same pressure in this invention.

[0029] Figure 3 E is the time curve for the degradation of chloramphenicol (CAP) in this invention;

[0030] Figure 3F is the apparent rate constant in this invention (wherein, the loading amount of MR-0 is 0 mg, the loading amount of MR-1 is 1 mg, the loading amount of MR-2 is 5 mg, the loading amount of MR-3 is 10 mg, the loading amount of MR-4 is 15 mg, and the loading amount of MR-5 is 20 mg).

[0031] Figure 4 A is the time curve of CAP degradation by membrane reactors loaded with different functional materials in this invention;

[0032] Figure 4 B is the apparent rate constant of the membrane reactor loaded with different functional materials in this invention;

[0033] Figure 4 C is the time curve of CAP degradation in the membrane reactor under dark and light conditions in this invention;

[0034] Figure 4 D is the curve showing the effect of pH value of CAP mother liquor on the degradation performance of membrane reactor in this invention;

[0035] Figure 5 A is a schematic diagram illustrating the enhanced interaction between CAP molecules and functional materials Pt / CuO2 JNPs due to the confinement effect in this invention;

[0036] Figure 5 B- Figure 5 D is the SEM scan image and pore size distribution of the PVDF membrane and membrane reactor surface pores in this invention;

[0037] Figure 5 E- Figure 5 F is a comparison graph of the degradation time curve and apparent rate constant of CAP molecules in the membrane reactor and homogeneous solution system in this invention.

[0038] Figure 6 A is the time curve of CAP degradation in the membrane reactor under different atmospheres in this invention;

[0039] Figure 6 B is the addition of different free radical scavengers (·OH scavenger TBA, ·O) in this invention. 2- Capture agent p-BQ, 1 Effect curves of O2 scavenger His and H2O2 scavenger CAT on the degradation performance of CAP in the reaction system;

[0040] Figure 6 C represents DMPO-·OH and DMPO-·O in the catalytic system of this invention. 2- and DMPO- 1 O2's ESR signal;

[0041] Figure 6D is the curve showing the change of H2O2 accumulation over time in different reaction systems in this invention;

[0042] Figure 6 E is the Cu added in this invention. 2+ With Cu + Effect curve of the trapping agent on the degradation performance of CAP in the reaction system;

[0043] Figure 6 F is the Cu 2p XPS spectrum of the functional material Pt / CuO2 JNPs before and after the reaction in this invention;

[0044] Figure 7 This is a schematic diagram of the mechanism of the membrane reactor prepared in this invention for the self-supply and self-catalytic H2O2 molecule confinement self-enhanced Fenton-like oxidation degradation of CAP under weak acid conditions;

[0045] Figure 8 A– Figure 8 B is the time curve of CAP degradation on different numbers of times the membrane reactor was reused and stored for different days in this invention;

[0046] Figure 8 C is the time curve of CAP degradation in the membrane reactor of this invention for different types of water samples exposed to it.

[0047] Figure 8 D is the time curve of CAP degradation in the membrane reactor when different substances coexist in the reaction system in this invention. Detailed Implementation

[0048] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0049] Example 1: Preparation of functional materials Figure 1 ).

[0050] (1) Synthesis of CuO2 NPs: 0.024 g of (CuNO3)2·3H2O and 2.5 g of polyvinylpyrrolidone (PVP, M w =111.48) was dissolved in 10 mL of ultrapure water. Then, NH3·H2O (10 mL, 1 M) and H2O2 (200 μL, 30%) were added sequentially to the mixed solution. After stirring for 30 min, the mixture was centrifuged at 10000 rpm for 10 min, washed three times with ultrapure water and ethanol solution, and the obtained CuO2 NPs were stored in anhydrous ethanol at 4 °C.

[0051] (2) Synthesis of Pt NPs: 2 mL of H₂PtCl₆ (0.02 M) and 20 mg of PVP were dissolved in 20 mL of deionized water to prepare Pt nanodendritic crystals. Then, 10 mL of ascorbic acid solution (0.003 M) was added dropwise to the above H₂PtCl₆ solution. After heating and stirring at 45 °C for 1 h, a dispersion of Pt NPs was prepared.

[0052] (3) Synthesis of Pt / CuO2 JNPs: 180 mg of CuO2 NPs prepared in step (1) was dispersed in 10 mL of 6.7% ethanol aqueous solution, and 200 μL of CTAB solution (1 μM) was added. The mixture was heated to 75 °C, and 1.2 mL of liquid paraffin was added. The mixture was stirred at 75 °C for 1 h to form a Pickering emulsion. After cooling to room temperature, the emulsion was diluted with 10 mL of methanol, and 200 μL of 3-mercaptopropyltrimethoxysilane was added to functionalize its surface. After stirring for 3 h, the resulting solid was centrifuged. After washing three times with methanol, the surface-thiol-functionalized CuO2 NPs were redispersed in 30 mL of the Pt NPs dispersion prepared in step (2). The mixture was stirred overnight at room temperature, and the resulting solid was centrifuged, filtered, washed with chloroform, and dried. Pt / CuO2 JNPs were thus prepared.

[0053] Example 2: Membrane preparation.

[0054] Accurately weigh 0.015 g of the prepared Pt / CuO2 JNPs and disperse them in 2.0 mL of deionized water. Sonicate for 20 min to ensure uniform dispersion. Further, load the Pt / CuO2 JNPs onto the surface of a PVDF membrane using vacuum filtration to prepare a membrane reactor. Store at 4℃.

[0055] Example 3: Characterization of materials.

[0056] like Figure 2 As shown in Figure A, before being combined with Pt NPs, the original CuO2 NPs exhibited nanospheres with a diameter of approximately 200 nm. Figure 2 Further magnification of the TEM image revealed that the CuO2 NPs had a uniform color distribution on their surface, indicating that the CuO2 NPs had a single crystal structure. Figure 2 High-resolution transmission electron microscopy (HRTEM) images further revealed lattice fringes with a width of 0.249 nm belonging to the CuO2 NPs(111) crystal plane. Figure 2 After Pt NPs in D are attached to the surface of CuO2 NPs, it can be clearly observed that the surface of CuO2 NPs is loaded with a large number of small particles (about 2 nm in diameter) with different crystal structures. Figure 2Further magnification of the TEM image reveals that the complex surface exhibits an uneven color distribution, indicating the presence of different crystal structures within the particles. Figure 2 FHRTEM data show that the newly emerging crystal structure has a lattice spacing of 0.230 nm, which is attributed to the (111) crystal plane of Pt NPs, proving the successful preparation of Pt / CuO2 JNPs.

[0057] Example 4: Degradation and application results of antibiotics.

[0058] A chloramphenicol solution of a certain concentration is filtered under reduced pressure through a pre-prepared membrane reactor to undergo an oxidative degradation reaction. Figure 7 ).

[0059] Figure 3 A. The prepared Pt / CuO2 JNPs were loaded onto the surface of a polyvinylidene fluoride (PVDF) membrane. Optical photographs show that the original PVDF membrane is white, while the membrane reactor becomes darker in color after functionalization with Pt / CuO2 JNPs. Furthermore, when the membrane reactor is bent or stretched, the surface-loaded functional material layer does not show obvious cracking or detachment, indicating that the prepared membrane reactor has good stability and mechanical strength. Figure 3 Scanning electron microscopy (SEM) characterized the surface morphology of the original PVDF membrane and the membrane reactor, revealing that the PVDF membrane possesses a rough, mesh-like surface and abundant internal pores. After being covered with Pt / CuO2 JNPs, the membrane surface became denser, indicating that the Pt / CuO2 JNPs have a certain pore-blocking effect, which helps reduce the porosity of the PVDF membrane surface and facilitates the nano-confinement effect on the membrane reactor surface, thereby enhancing the catalytic degradation performance of CAP by the membrane reactor. A comparison of cross-sectional SEM images before and after membrane modification shows that the thickness of the Pt / CuO2 JNPs layer is approximately 40 μm. Figure 3 Contact angle experiments revealed that the contact angle of a water droplet on the surface of the original PVDF membrane was 60.7°. However, the contact angle of the membrane reactor modified with a Pt / CuO2 JNPs layer was 43.6°. This indicates that the hydrophilicity of the membrane was improved after modification with Pt / CuO2 JNPs. This improved hydrophilicity allows antibiotic molecules to easily migrate into the reactor and react, which is beneficial for the application of the prepared membrane in highly polar aqueous solutions. Figure 3 Compared to the original PVDF membrane, the water flux of the membrane reactor modified with Pt / CuO2 JNPs is slightly reduced under the same pressure because the functional material Pt / CuO2 JNPs enters the voids inside the PVDF membrane. Figure 3 With the increase of E Pt / CuO2JNPs loading, the degradation efficiency of CAP in membrane reactors MR-0 to MR-4 gradually increased, but when the loading continued to increase, the degradation efficiency of CAP in MR-5 did not increase significantly. Figure 3 Taking into account both membrane flux and reaction efficiency, a first-order kinetic model was used to fit the apparent rate constant of CAP degradation in the prepared membrane reactor. The results show that the prepared membrane reactor (MR-4) has the best catalytic degradation efficiency for CAP when the Pt / CuO2 JNPs loading is 15 mg.

[0060] like Figure 4 As shown, the degradation curves of CAP for membrane reactors modified with Pt NPs or CuO2 NPs and membrane reactors functionalized with Pt / CuO2 JNPs are compared and analyzed. Figure 4 A) and apparent rate constant ( Figure 4 B). The results show that the membrane reactor modified with Pt NPs alone has almost negligible degradation efficiency for CAP. In addition, the PVDF membrane modified with CuO2 NPs exhibits a certain degradation efficiency for CAP, which may be due to the presence of Cu... 2+ / Cu + Cyclic-mediated H2O2 activation generates reactive oxygen species that contribute to CAP degradation. The PVDF membrane modified with Pt / CuO2 JNPs exhibits the best performance in catalytic CAP degradation, indicating that the synergistic catalytic H2O2 activation by Pt NPs plays a crucial role in enhancing the efficiency of membrane reactor catalytic CAP degradation. Figure 4 Under both light and dark conditions, the membrane reactor showed no significant difference in degradation efficiency for CAP, indicating that the catalytic degradation of CAP by the membrane reactor is independent of light. Compared to photocatalytic degradation technology for antibiotics, the membrane reactor developed in this invention can be used "around the clock". Figure 4 D. The effect of the pH of the antibiotic mother liquor on the catalytic degradation of CAP by the membrane reactor was investigated. The results showed that the membrane reactor could exhibit good CAP removal efficiency under natural acidic conditions (pH=5.0). Obviously, compared with the traditional Fenton oxidation technology which requires strong acid conditions, the Fenton-like oxidation membrane developed in this invention has better applicability and environmental friendliness.

[0061] Figure 5 A is a schematic diagram illustrating the enhanced interaction between CAP and functional material Pt / CuO2 JNPs due to the nanoconfinement effect on the membrane reactor surface. SEM images of the surface pores of Pt / CuO2 JNPs before and after PVDF membrane modification are also shown. Figure 5 B Figure 5 C). The images clearly show that the porosity on the membrane surface is significantly reduced. Figure 5BET pore size analysis in D further confirmed the "pore-blocking" effect of the functional material Pt / CuO2JNPs. The diameter of the pores on the membrane reactor surface was significantly reduced from 31 nm before modification to about 21 nm, and a large number of pores smaller than 10 nm appeared. Obviously, this is beneficial to the confinement effect of the membrane reactor. The effect of the membrane reactor on improving the CAP degradation efficiency is further illustrated by comparing the degradation efficiency of the membrane reactor with that of the functional material directly dispersed in the solution system. The results show that the degradation efficiency of CAP by the membrane reactor is higher than that of the same amount of Pt / CuO2JNPs dispersed in a homogeneous solution. Figure 5 E) and apparent rate constant ( Figure 5 F) is almost twice as high.

[0062] Figure 6 A comparison of the degradation efficiency of CAP by the membrane reactor before and after N2 deoxygenation. Experimental results show that when nitrogen is continuously injected into the reaction system to remove dissolved O2, the degradation efficiency of CAP by the membrane reactor decreases from 97.7% to 17.8%. This indicates that the activation of molecular O2 in the reaction system plays an important role in the degradation of CAP. Figure 6 tert-butanol (TBA), p-benzoquinone (p-BQ), histidine (His), and catalase (CAT) act as hydroxyl radicals (·OH), superoxide radicals (·O), and hydroxyl radicals (·OH), respectively. 2- ), singlet oxygen ( 1 When O2 and H2O2 scavengers were added to the reaction system, the degradation effect of CAP was significantly weakened, indicating that ·OH and ·O2 scavengers were present in the CAP. 2- , 1 O2 and H2O2 are the main reactive oxygen species in the CAP degradation process. Figure 6 The C electron spin resonance (ESR) experiment further confirmed the presence of ·OH and ·O2 in the reaction system. - , 1 The presence of O2. Figure 6 The change in the accumulation of H2O2 in the D reaction system indicates that H2O2 can be self-supplied and self-catalyzed in the reaction system. Figure 6 E Cu 2+ With Cu + The capture experiment investigated the presence of Cu in the reaction system. 2+ and Cu + The effect of Cu on CAP degradation. Results showed that Cu 2+ / Cu + Cycling also plays an important role in CAP degradation. Figure 6 XPS spectra of the functional materials on the membrane reactor surface before and after the F reaction further confirmed the presence of Cu on the membrane reactor surface during the catalytic degradation process. 2+ / Cu + cycle.

[0063] Figure 8 After five consecutive batches of use (approximately 6.5 hours in total), the catalytic efficiency of membrane reactor A for CAP degradation decreased from 94.3% to 87.5%, indicating that the membrane reactor has good operational stability. Figure 8 The membrane reactor in section B showed no significant difference in CAP degradation efficiency after being stored at 4℃ for 1, 5, 10, 15 and 20 days, respectively, indicating that it has good storage stability. Figure 8 C represents the degradation efficiency of the membrane reactor for antibiotics exposed in actual water samples. Using tap water and water from Qingshan Lake in Huangshi as actual samples, the degradation efficiency of the membrane reactor for CAP did not change significantly compared to the pure water system. This indicates that the catalytic performance of the reactor is not affected by the presence of impurities or pollutants in the actual water. Figure 8 In step D, ions commonly found in real-world aquatic environments (Cl-) are added to the reaction system. - SO4 2- PO4 3- The presence of ions and dissolved organic matter (humic acid) showed that the degradation efficiency of CAP was not significantly affected by the presence of ions, while the degradation efficiency decreased slightly in the presence of reducing humic acid, mainly due to competitive reactions. These results indicate that the prepared membrane reactor has good stability in use and storage, and is practically applicable to real water samples.

[0064] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A Fenton-like oxidizing agent, characterized in that, Its preparation method includes the following steps: (1) Synthesis of CuO2 NPs: Cu(NO3)2•3H2O and polyvinylpyrrolidone (PVP) were dissolved in ultrapure water, and NH3•H2O and H2O2 were added to the above mixed solution in sequence; after stirring and centrifugation, the solution was washed multiple times with ultrapure water and anhydrous ethanol to obtain CuO2 NPs. (2) Synthesis of Pt NPs: H2PtCl6 and PVP were dissolved in deionized water to prepare Pt nano-dendritic crystals; then, ascorbic acid solution was added dropwise to the above H2PtCl6 solution, and after stirring at 45°C, a dispersion of Pt NPs was prepared. (3) Synthesis of Pt / CuO2 JNPs: The CuO2 NPs prepared in step (1) were dispersed in a 6.7% ethanol aqueous solution and CTAB solution was added. The mixture was heated to 75°C and liquid paraffin was added. The mixture was stirred at 75°C to form a Pickering emulsion. The mixture was cooled to room temperature and diluted with methanol. 3-mercaptopropyltrimethoxysilane was added to the emulsion to functionalize its surface. After stirring, the solid was centrifuged. After washing with methanol several times, the surface thiol-functionalized CuO2 NPs were redispersed in the Pt NPs dispersion prepared in step (2). The mixture was stirred at room temperature overnight. The solid was centrifuged and filtered, washed with chloroform and dried to prepare Pt / CuO2 JNPs.

2. The Fenton-like oxidant according to claim 1, characterized in that, In step (1), 0.024 g Cu(NO3)2•3H2O and 2.5 g polyvinylpyrrolidone were dissolved in 10 mL of ultrapure water. Then, 10 mL of 1 M NH3•H2O and 200 μL of 30% H2O2 were added to the mixed solution in sequence. After stirring for 30 min, the solution was centrifuged at 10000 rpm for 10 min. The solution was washed three times with ultrapure water and ethanol solution. The obtained CuO2 NPs were stored in anhydrous ethanol at 4 °C.

3. The Fenton-like oxidant according to claim 1, characterized in that, In step (2), 2 mL of 0.02 M H2PtCl6 and 20 mg PVP were dissolved in 20 mL of deionized water to prepare Pt nanodendritic crystals. 10 mL of 0.003 M ascorbic acid solution was added dropwise to the above H2PtCl6 solution, and the mixture was heated and stirred at 45 °C for 1 h to prepare a dispersion of PtNPs.

4. The Fenton-like oxidant according to claim 1, characterized in that, In step (3), 180 mg of CuO2 NPs prepared in step (1) are dispersed in 10 mL of 6.7% ethanol aqueous solution, 200 μL of 1 μM CTAB solution is added, the mixture is heated to 75 °C, 1.2 mL of liquid paraffin is added, and the mixture is stirred at 75 °C for 1 h to form a Pickering emulsion. After cooling to room temperature, the emulsion is diluted with 10 mL of methanol, and 200 µL of 3-mercaptopropyltrimethoxysilane is added to it to functionalize its surface. After stirring for 3 h, the resulting solid is centrifuged. After washing with methanol 3 times, the surface thiol-functionalized CuO2 NPs are redispersed in 30 mL of the Pt NPs dispersion prepared in step (2). The mixture is stirred at room temperature overnight, the resulting solid is centrifuged and filtered, washed with chloroform and dried to prepare Pt / CuO2 JNPs.

5. A Fenton-like oxide film, characterized in that, The method for preparing the Fenton-like oxide film includes the following steps: dispersing the prepared Fenton-like oxidant as described in any one of claims 1-4 in deionized water, sonicating, and then loading Pt / CuO2 JNPs onto the surface of a PVDF membrane by vacuum filtration to obtain the Fenton-like oxide film.

6. The Fenton-like oxide film according to claim 5, characterized in that, The ultrasonic time is 20-40 min, and the prepared Fenton-like oxide film is stored at 4℃.

7. The application of a Fenton-like oxide film as described in claim 5 or 6 in the environment for antibiotic degradation.

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