K / FeS / g-C3N4 / TiO2 coated PVDF (Polyvinylidene Fluoride) membrane for photocatalytic oxidation as well as preparation method and application thereof

Abstract

The invention discloses a K / FeS / g-C3N4 / TiO2 (at) PVDF membrane for photocatalytic oxidation, a preparation method and application, through SO2 and CO2 generated by pyrolysis of K4 [Fe (CN) 6] and K2SO3, gaps are generated in a microstructure of g-C3N4, the specific surface area is higher, adsorption of organic pollutants is enhanced, the reaction rate is increased, a FeS / g-C3N4 / TiO2 heterojunction structure is constructed, and the photocatalytic oxidation performance of the membrane is improved. And carbon defects or nitrogen defects generated by K ionization are introduced into the structure, so that stable electron channel connection and light energy absorption and conversion paths are realized, the light response efficiency is improved, the recombination rate of photo-generated electron holes is reduced, and the free radical yield is improved. The membrane material is applied to a circulating aquaculture water body treatment system, odor substances are degraded through photocatalytic oxidation, and deep purification of water is achieved.

Description

Technical Field

[0001] This invention belongs to the field of environmental engineering water treatment technology, specifically involving photocatalytic membrane materials, preparation methods, and applications in odor purification of recirculating aquaculture water. Background Technology

[0002] With the increasing demand for aquatic products, the aquaculture industry faces increasingly stringent requirements for wastewater discharge and environmental protection pressures. Recirculating aquaculture systems (RAS) can integrate multiple water treatment technologies to create a closed aquaculture model, achieving a water recycling rate of over 95%. However, during the continuous circulation of aquaculture water, various pollutants gradually accumulate, easily leading to severe deterioration of aquaculture water quality. Odor-causing substances such as geosmin (GSM) and 2-methylisoborneol (2-MIB) can also cause aquatic products to have a noticeable odor, significantly impacting their quality. Commonly used physicochemical methods such as filtration, coagulation, sedimentation, or biological methods are ineffective in treating odor-causing substances, only offering temporary relief through activated carbon adsorption or dilution with large amounts of clean water.

[0003] Photocatalytic oxidation technology is a novel water treatment technology. Under ultraviolet light, photocatalysts generate highly oxidizing free radicals, efficiently and environmentally degrading COD and odor-causing substances. It has broad application prospects and enormous industrialization potential in recirculating aquaculture systems. Traditional TiO2 photocatalysts can only generate free radicals under ultraviolet irradiation, greatly limiting their application scenarios and reaction rates. Furthermore, they suffer from drawbacks such as high photo-generated electron-hole recombination rates and poor free radical generation efficiency.

[0004] In recent years, carbon-based materials, especially graphitic carbon nitride (g-C3N4), have gradually become novel materials for improving the photocatalytic performance of TiO2 due to their unique layered microstructure, good chemical stability, and conductivity. However, the two-dimensional layered structure of bulk g-C3N4 prepared by conventional methods is prone to multilayer stacking, resulting in the following technical defects: (1) low efficiency of photogenerated electron separation and fast hole recombination rate; (2) lack of surface defects and atomic vacancies, limiting redox kinetics; (3) lack of gaps between layered structures, resulting in insufficient exposure of active sites.

[0005] Furthermore, by simply mixing g-C3N4 with TiO2 nanomaterials, the resulting material is bound only by electrostatic adsorption and lacks a stable electron transfer channel. Therefore, it cannot effectively improve photocatalytic efficiency and free radical yield, and it also suffers from high loss rate, poor stability, and difficulty in recycling and reuse, which can easily lead to secondary pollution risks.

[0006] Based on the current research status, how to effectively modify g-C3N4 / TiO2 materials to prepare photocatalysts with excellent performance and effectively apply them in the treatment of odor substances in aquaculture wastewater is of great practical significance and urgent need for the green, low-carbon, safe and efficient development of circular aquaculture. Summary of the Invention

[0007] Based on the problems existing in the prior art, the purpose of this invention is to provide a photocatalytic membrane material, its preparation method, and its application.

[0008] In a first aspect, the present invention provides a method for preparing a K / FeS / g-C3N4 / TiO2@PVDF membrane for photocatalytic oxidation, comprising the following steps:

[0009] 1) TiO2 powder was ultrasonically dispersed in deionized water, and K4[Fe(CN)6] solution, K2SO3 solution and melamine solution were added while stirring and mixed evenly; after vacuum freeze-drying, it was calcined under N2 protection, washed, dried and ground to obtain K / FeS / g-C3N4 / TiO2 material with heterojunction structure;

[0010] 2) Mix PVDF powder and N,N-dimethylformamide, heat and sonicate to dissolve to obtain a mixed solution;

[0011] 3) Place the K / FeS / g-C3N4 / TiO2 material into the mixed solution obtained in step 2) and stir thoroughly. Filter and degas under vacuum to obtain the casting solution.

[0012] 4) The casting solution obtained in step 3) is uniformly coated onto a glass plate using a flatbed coating machine, and then placed in a gel bath for solidification to obtain a K / FeS / g-C3N4 / TiO2@PVDF membrane.

[0013] Furthermore, the mass ratio of TiO2, K4[Fe(CN)6], K2SO3, and melamine is 100:0.1~5:0.5~10:5~50, with a preferred ratio of 100:2:4:20.

[0014] Furthermore, in step 1), the calcination temperature is 600℃ and the calcination time is 3-6h.

[0015] Furthermore, the mass concentration of PVDF in the mixed solution is 7-10%.

[0016] Further, in step 2), the mixture is heated in a 50°C water bath and sonicated for 2 hours.

[0017] Furthermore, the mass concentration of K / FeS / g-C3N4 / TiO2 material in the casting solution is 0.5~10‰.

[0018] Further, in step 3), the membrane is placed in a gel bath and soaked in deionized water for 24 hours, and then solidified to obtain a K / FeS / g-C3N4 / TiO2@PVDF membrane.

[0019] In a second aspect, the present invention provides a K / FeS / g-C3N4 / TiO2@PVDF membrane prepared by the preparation method described in the first aspect.

[0020] Thirdly, the present invention provides the application of the K / FeS / g-C3N4 / TiO2@PVDF membrane prepared by the preparation method described in the first aspect in the photocatalytic oxidation removal of odor pollutants in circulating aquaculture water.

[0021] Furthermore, the odor contaminants are any one or both of 2-MIB (2-methylisoborneol) and GSM (geosin).

[0022] Furthermore, the K / FeS / g-C3N4 / TiO2@PVDF membrane was placed in aquaculture wastewater containing a certain concentration of odor pollutants, and a photocatalytic oxidation reaction was carried out under ultraviolet light and stirring.

[0023] Furthermore, the ultraviolet light intensity is 50-200 mW / cm². 2 The wavelength is 365nm; the stirring speed is 300-800rpm.

[0024] Furthermore, for aquaculture wastewater containing 100-500 ng / L of odor pollutants, the water treatment capacity per unit area membrane is 5-25 L / (m²). 2 ·h).

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1) The preparation process of this invention is short, the conditions are simple, and the cost is low, which has high economic value and practical value.

[0027] 2) This invention generates SO2 and CO2 by pyrolyzing K4[Fe(CN)6] and K2SO3, which creates voids in the microstructure of g-C3N4, resulting in a higher specific surface area, enhanced adsorption of organic pollutants, and increased reaction rate.

[0028] 3) This invention constructs a FeS / g-C3N4 / TiO2 heterojunction structure and introduces carbon or nitrogen defects generated by K ionization into the structure, thereby realizing stable electron channel connection and light energy absorption and conversion path, improving photoresponse efficiency, reducing the recombination rate of photogenerated electrons and holes, and improving free radical yield.

[0029] 4) This invention uses PVDF membrane as a substrate, which effectively solves the problem of difficult recycling of K / FeS / g-C3N4 / TiO2 photocatalytic materials. It is simple to manufacture and conducive to large-scale application.

[0030] 5) This invention uses K / FeS / g-C3N4 / TiO2@PVDF membrane to treat organic pollutants and odor substances in aquaculture water, providing a simple, effective, and low-cost treatment method for deep purification of aquaculture water. Attached Figure Description

[0031] Figure 1 The image shows a scanning electron microscope image of g-C3N4 obtained by direct pyrolysis at 7000x magnification.

[0032] Figure 2 In the figures, A and B are scanning electron microscope images of the K / FeS / g-C3N4 / TiO2 material obtained in Example 1 at 1300x and 7000x magnification, respectively. Figure 2 C, D, E, and F in the figure are EDS diagrams of Fe, N, C, and S elements, respectively;

[0033] Figure 3 The examples and comparative examples illustrate the photocatalytic oxidation degradation effect of the membrane materials obtained, where A represents the degradation effect of GSM and B represents the degradation effect of 2-MIB.

[0034] Figure 4 The degradation effects of the membrane materials obtained in the examples and comparative examples were tested in five batches. A represents the effect of photocatalytic oxidation degradation of GSM, and B represents the effect of degradation of 2-MIB.

[0035] Figure 5 The specific surface area (BET) test results of the materials obtained in step 1) of Examples 1 and Comparative Examples 1-5 are shown. Detailed Implementation

[0036] The present application will be further described below with reference to specific embodiments.

[0037] It should be noted that terms such as "upper", "lower", "left", "right", and "middle" used in this specification are only for clarity of description and are not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered as within the scope of this application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0039] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0040] As used herein, the term “about” is used to provide for the flexibility and imprecision associated with a given term, measure, or value. Those skilled in the art can readily determine the degree of flexibility for a particular variable.

[0041] As used herein, the term “at least one of…” is intended to be synonymous with “one or more of…”. For example, “at least one of A, B, and C” explicitly includes only A, only B, only C, and combinations thereof.

[0042] Concentration, amount, and other numerical data may be presented in range format herein. It should be understood that such range format is used solely for convenience and brevity and should be flexibly interpreted to include not only the values ​​explicitly stated as the limits of the range, but also all individual values ​​or subranges encompassed within the range, as if each value and subrange were explicitly stated. For example, a range of values ​​from about 1 to about 4.5 should be interpreted to include not only the explicitly stated limits of 1 to 4.5, but also individual numbers (such as 2, 3, 4) and subranges (such as 1 to 3, 2 to 4, etc.). The same principle applies to ranges that describe only a single value, such as "less than about 4.5," which should be interpreted to include all the values ​​and ranges described above. Furthermore, this interpretation should apply regardless of the breadth of the range or characteristic described.

[0043] The overall concept of this invention is as follows: K4[Fe(CN)6] is used as the iron source. K4[Fe(CN)6], K2SO3, and melamine are mixed in solution and then freeze-dried to uniformly disperse them on the surface of TiO2. The mixture is then calcined at high temperature under N2 protection to obtain a heterojunction K / FeS / g-C3N4 / TiO2 material. Melamine pyrolysis produces g-C3N4, and the SO2 and CO2 gases generated by the pyrolysis of K4[Fe(CN)6] and K2SO3 create voids between the micro-layered structures of g-C3N4, resulting in a higher specific surface area. Sulfur reacts with K4[Fe(CN)6] under high temperature and K2SO3 reducing conditions to produce FeS, which embeds into the voids of g-C3N4, forming a heterojunction structure while protecting FeS from oxidation. Furthermore, potassium (K) occupies space in g-C3N4, forming nitrogen or carbon defects in water, thus improving the material's light conversion efficiency. Then, K / FeS / g-C3N4 / TiO2 material was loaded onto the surface of a PVDF membrane using a phase inversion method to construct a membrane material with high-efficiency photocatalytic oxidation performance. This membrane material was then applied to a recirculating aquaculture water treatment system to utilize photocatalytic oxidation to degrade odor substances and achieve deep purification of water quality.

[0044] Example 1

[0045] A K / FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0046] 1) Add 0.01g K4[Fe(CN)6], 0.02g K2SO3, and 0.1g melamine to 100mL of deionized water and stir until dissolved. Then add 0.5g TiO2 powder and sonicate for 30min to disperse evenly. The solution is freeze-dried under vacuum to obtain a solid, which is then calcined at 600℃ for 4h under N2 protection at a heating rate of 5℃ / min. The product is washed with deionized water, dried, and ground to obtain the K / FeS / g-C3N4 / TiO2 material.

[0047] 2) Mix 0.8g of PVDF powder and 9.2g of N,N-dimethylformamide, dissolve by ultrasonication at 50℃, and heat in a water bath for 2h to obtain a mixed solution.

[0048] 3) Weigh 0.05g of K / FeS / g-C3N4 / TiO2 material and add it to 10g of the mixed solution obtained in step 2). Mix thoroughly, filter through a 100-mesh filter, and vacuum degas for 30 minutes to obtain the casting solution for later use.

[0049] 4) Pour the casting solution obtained in step 3) onto a 100mm×100mm horizontal glass plate, spread it evenly with a scraper, immerse the glass plate in deionized water for 24 hours, and solidify to obtain K / FeS / g-C3N4 / TiO2@PVDF membrane.

[0050] Comparative Example 1

[0051] A K / FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0052] The difference from Example 1 is that in step 1), 0.5g TiO2 powder, 0.1g melamine, 0.0073g FeCl3·6H2O (Fe element content is the same as 0.01g K4[Fe(CN)6]) and 0.02g K2SO3 are mixed and calcined under the same conditions to obtain K / FeS / g-C3N4 / TiO2 material.

[0053] Comparative Example 2

[0054] A K / FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0055] The difference from Example 1 is that in step 1), 0.5g TiO2 powder, 0.1g melamine, 0.0075g FeSO4·7H2O (Fe element content is the same as 0.01g K4[Fe(CN)6]) and 0.02g K2SO3 are mixed and calcined under the same conditions to obtain K / FeS / g-C3N4 / TiO2 material.

[0056] Comparative Example 3

[0057] A FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0058] The difference from Example 1 is that in step 1), 0.5g TiO2 powder, 0.1g melamine and 0.0024g FeS (Fe element content is the same as 0.01g K4[Fe(CN)6]) are mixed and calcined under the same conditions to obtain FeS / g-C3N4 / TiO2 material.

[0059] Comparative Example 4

[0060] A FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0061] The difference from Example 1 is that in step 1), 0.5g TiO2 powder, 0.1g melamine, 0.01g K4[Fe(CN)6] and 0.004g sulfur powder (with the same S element content as 0.02g K2SO3) were mixed and calcined under the same conditions to obtain K / FeS / g-C3N4 / TiO2 material.

[0062] Comparative Example 5

[0063] A FeS / g-C3N4 / TiO2@PVDF membrane and its preparation method, comprising the following steps:

[0064] The difference from Example 1 is that in step 1), FeS / g-C3N4 / TiO2 material was obtained by calcination in air.

[0065] Figure 1 This is a scanning electron microscope image of g-C3N4 obtained by direct pyrolysis at 7000x magnification. Figure 2 In the figures, A and B are scanning electron microscope images of the K / FeS / g-C3N4 / TiO2 material obtained in Example 1 at 1300x and 7000x magnification, respectively. Figure 2 C, D, E, and F in the figure are EDS diagrams of Fe, N, C, and S elements, respectively. It can be seen that, unlike the blocky g-C3N4 obtained by direct pyrolysis, the material obtained by the method described in Example 1 of this invention has a distinct microporous structure, and the Fe and S elements are uniformly distributed and tightly bound in the CN structure.

[0066] Application Example 1

[0067] A method for removing typical odor substances from recirculating aquaculture water using membrane photocatalytic oxidation obtained in Example 1 and Comparative Examples 1-5 includes the following steps:

[0068] Cut membranes with a diameter of 60 mm from Examples 1 and Comparative Examples 1-5, and evenly attach them to the bottom of a jacketed beaker. Add 50 mL of a 100 ng / L mixed solution of GSM and 2-MIB to the beaker, and stir in the dark for 30 min to reach adsorption / desorption equilibrium. The mixture is then subjected to a light intensity of 100 mW / cm². 2 Photocatalytic oxidation was carried out under 365 nm ultraviolet light irradiation for 1 h. 2 mL samples were taken every 10 min, filtered through a 0.45 μm filter, and the concentrations of 2-MIB and GSM in the samples were quantitatively analyzed using headspace solid-phase microextraction (HS-SPME) / gas chromatography-mass spectrometry (GC-MS). The ratios of GSM and 2-MIB concentrations at each time point to their initial concentrations before the reaction were calculated, and the removal rates were calculated. The results are shown in [Figure number missing]. Figure 3 ,in Figure 3 In this context, A represents the effect of photocatalytic oxidation degradation of GSM. Figure 3 In this context, B represents the effect of degrading 2-MIB.

[0069] from Figure 3 It can be seen that the membrane material of Example 1 exhibits high degradation efficiency for both GSM and 2-MIB under ultraviolet photocatalysis. Within a 1-hour reaction time, the degradation rate of both odor substances by the membrane is higher than 97%. Specifically, the degradation rate for GSM is 98.6%, and the degradation rate for 2-MIB is 97.3%. The degradation rates of GSM by the membranes of Comparative Examples 1-5 are 76.5%, 79.5%, 34.0%, 42.6%, and 62.5%, respectively, and the degradation rates for 2-MIB are 72.5%, 80.6%, 40.7%, 39.0%, and 55.2%, respectively.

[0070] Application Example 2

[0071] A method for removing typical odor substances from recirculating aquaculture water using the membranes obtained in Examples 1-5 through five-batch cyclic photocatalytic oxidation includes the following steps:

[0072] Cut membranes with a diameter of 60 mm from Examples 1 and Comparative Examples 1-5, and evenly attach them to the bottom of a jacketed beaker. Add 50 mL of a 100 ng / L mixed solution of GSM and 2-MIB to the beaker, and stir in the dark for 30 min to reach adsorption / desorption equilibrium. The mixture is then subjected to a light intensity of 100 mW / cm². 2 Photocatalytic oxidation was carried out under 365 nm ultraviolet light irradiation. After 1 h of reaction, 2 mL of sample was taken, filtered through a 0.45 μm filter, and the concentrations of 2-MIB and GSM in the sample were quantitatively analyzed using a headspace solid-phase microextraction (HS-SPME) / gas chromatography-mass spectrometry (GC-MS) system. The membrane material was recovered after each reaction, washed with deionized water, and the above steps were repeated 5 times. The ratios of the concentrations of GSM and 2-MIB in each group and each cycle batch to the initial concentrations before the reaction were calculated, and the removal rate was calculated. The results are shown in [Figure number missing]. Figure 4 ,in Figure 4 In this context, A represents the effect of photocatalytic oxidation degradation of GSM. Figure 4 In the figure, B represents the degradation effect of 2-MIB. After 5 cycles, the material obtained in Example 1 still maintained a degradation rate of 96.6% for GSM and 94.4% for 2-MIB after 1 hour, while the degradation rates of the other comparative materials were all below 70%. This indicates that the K / FeS / g-C3N4 / TiO2@PVDF membrane has high reusability and its catalytic activity does not decrease significantly with increasing usage time.

[0073] Figure 5The specific surface area test results are for the materials obtained in step 1) of Examples 1 and Comparative Examples 1-5. It can be seen that the specific surface area of ​​the material obtained in Example 1 is significantly higher than that of all comparative examples, reaching 58.4 m². 2 / g. Comparative Examples 3 and 4 used FeS and sulfur powder instead of K2SO3, and no SO2 or CO2 gases were generated during the N2 protected calcination process. Their specific surface areas were only 13.5 and 14.8 m², respectively. 2 The SO2 and CO2 gases produced by the pyrolysis of K4[Fe(CN)6] and K2SO3 create voids between the micro-layered structures of g-C3N4, resulting in a higher specific surface area. If the added raw materials do not contain oxygen, it is difficult to generate a large amount of gas during calcination under N2 protection, thus failing to produce a large number of microporous structures. The specific surface area of ​​the material is positively correlated with its ability to degrade odor substances, indicating that as the specific surface area increases, the adsorption capacity for odor substances is stronger, more active sites are exposed, and the production of strong oxidizing free radicals is higher.

[0074] Table 1. XRF analysis of the elemental composition of the surface of six materials

[0075]

[0076] Table 1 shows the analysis of the surface elemental composition of the six materials by X-ray fluorescence spectrometry (XRF). It can be seen that the Fe:S mass ratio in the material obtained in Example 1 is 0.27:0.18, with a molar ratio close to 1:1, indicating that most of it exists in the form of FeS. The high proportion of K forms defect structures in the material structure that can ionize in water, providing active sites for photogenerated electrons. Comparative Examples 1 and 2 used FeCl3·6H2O and FeSO4·7H2O as iron sources, respectively. During calcination, they failed to form effective bonds with the CN structure, resulting in a significant loss of Fe during water washing and a decrease in the Fe content on the product surface. Comparative Example 3 directly added FeS for calcination. Due to its instability in air and easy oxidation, the FeS form in the product decreased, affecting its catalytic activity. Comparative Example 5 was obtained by calcination in air, where S was oxidized to SO2, resulting in Fe mainly existing in the form of oxides in the product, thus losing the photocatalytic activity of FeS.

[0077] The K / FeS / g-C3N4 / TiO2@PVDF membrane of the present invention, through multi-component composite synergy, regulates the transfer path of photogenerated electrons, improves charge transfer efficiency, significantly enhances photocatalytic activity and free radical yield, and promotes the degradation of typical odor substances such as GSM and 2-MIB. It has the advantages of being green, low-carbon, and free from secondary pollution.

[0078] The above embodiments are merely preferred embodiments of the present invention, but the implementation of the present invention is not limited to the above embodiments. Any changes, modifications, substitutions, or combinations made without departing from the spirit and principle of the present invention, such as various combinations of solutions in the embodiments, should be considered equivalent replacements and are all within the protection scope of the present invention.

Claims

1. A method for preparing a K / FeS / g-C3N4 / TiO2@PVDF membrane for photocatalytic oxidation, characterized in that, Includes the following steps: 1) TiO2 powder was ultrasonically dispersed in deionized water, and K4[Fe(CN)6] solution, K2SO3 solution and melamine solution were added while stirring and mixed evenly; after vacuum freeze-drying, it was calcined under N2 protection, washed, dried and ground to obtain K / FeS / g-C3N4 / TiO2 material with heterojunction structure; 2) Mix PVDF powder and N,N-dimethylformamide, heat and sonicate to dissolve to obtain a mixed solution; 3) Place the K / FeS / g-C3N4 / TiO2 material into the mixed solution obtained in step 2) and stir thoroughly. Filter and degas under vacuum to obtain the casting solution. 4) The casting solution obtained in step 3) is uniformly coated onto a glass plate using a flatbed coating machine, and then placed in a gel bath for solidification to obtain a K / FeS / g-C3N4 / TiO2@PVDF membrane.

2. The preparation method according to claim 1, characterized in that, The mass ratio of TiO2, K4[Fe(CN)6], K2SO3, and melamine is 100:0.1~5:0.5~10:5~50, with a preferred mass ratio of 100:2:4:

20.

3. The preparation method according to claim 1, characterized in that, The calcination temperature is 600℃ and the calcination time is 3-6 hours.

4. The preparation method according to claim 1, characterized in that, The mass concentration of PVDF in the mixed solution is 7-10%.

5. The preparation method according to claim 1, characterized in that, The mass concentration of K / FeS / g-C3N4 / TiO2 material in the casting solution is 0.5~10‰.

6. A K / FeS / g-C3N4 / TiO2@PVDF membrane prepared by any one of the preparation methods described in claims 1-5.

7. The application of a K / FeS / g-C3N4 / TiO2@PVDF membrane prepared by any one of the preparation methods described in claims 1-5 in the photocatalytic oxidation removal of odor pollutants in circulating aquaculture water.

8. The application as described in claim 7, characterized in that, The odor pollutant is any one or both of 2-methylisoborneol and geosmin.

9. The application as described in claim 7, characterized in that, The specific steps are as follows: Place the K / FeS / g-C3N4 / TiO2@PVDF membrane in the aquaculture wastewater containing odor pollutants, and carry out a photocatalytic oxidation reaction under ultraviolet light and stirring.

10. The application as described in claim 9, characterized in that, Ultraviolet light intensity is 50-200 mW / cm 2 The wavelength is 365nm; the stirring speed is 300-800rpm; for aquaculture wastewater containing 100-500ng / L of odor pollutants, the water treatment capacity per unit area membrane is 5-25L / (m²). 2 ·h).

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