Preparation method of organic matter photocatalysis-peroxysulfate coupling degradation agent in aquaculture wastewater

Abstract

The application discloses a preparation method of an organic matter photocatalysis-peroxysulfate coupling degradation agent in aquaculture wastewater, and comprises the following steps: (1) Mg-Al-Fe water slurry powder is calcined and then placed in a saturated iron ion source solution, and after standing, the powder is separated out, and a sodium borohydride solution is added to the powder for reaction; after the reaction is completed, a solid product is separated out and subjected to thermal reduction treatment, then the obtained modified powder is uniformly mixed with a polyethylene glycol aqueous solution, granulation is conducted, and after drying, a catalyst core is obtained; (2) titanium dioxide particles, low-melting-point glass powder and a binder are uniformly mixed to form a slurry; then the catalyst core is placed in the slurry to obtain a green body with a coating layer on the surface; and (3) the green body is subjected to heat treatment in an air atmosphere, and the degradation agent is obtained.The degradation agent can simultaneously perform photocatalysis and peroxysulfate advanced oxidation coupling degradation on the organic matter in the aquaculture wastewater, and has the characteristics of high degradation efficiency and good degradation effect.

Description

Technical Field

[0001] This invention relates to the field of organic wastewater treatment, specifically to a method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] With global population growth and increasing demand for high-quality protein, aquaculture, including fish farming, has become one of the fastest-growing food production sectors. However, while intensive, high-density farming methods bring high yields, they also generate large amounts of aquaculture wastewater rich in organic matter. If untreated feed and excrement in this wastewater are discharged directly, they will pose a serious risk of eutrophication to surrounding waters and disrupt the aquatic ecosystem.

[0004] The main sources of dissolved organic matter in aquaculture wastewater include: uneaten feed that sinks to the bottom during artificial feeding, which is the primary source of organic pollution in the early stages of aquaculture; and metabolic products of farmed organisms, including feces and excrement, which contain large amounts of protein, fat, and carbohydrates. These organic compounds are complex in composition, and the gradual degradation of high concentrations of organic matter by microorganisms consumes dissolved oxygen (DO) in the water, leading to oxygen deficiency or stress in farmed organisms such as fish, and even death. Therefore, how to efficiently degrade organic matter in aquaculture wastewater has become a core issue for the green and sustainable development of the aquaculture industry. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater. This degradation agent can simultaneously perform photocatalytic and advanced persulfate oxidation coupled degradation of organic matter in aquaculture wastewater, exhibiting high degradation efficiency and good degradation effect. Specifically, the technical solution of this invention is as follows.

[0006] A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater includes the following steps: (1) After calcining Mg-Al-Fe hydrotalcite powder, it was placed in a saturated iron ion source solution, allowed to stand, and then the powder was separated. Sodium borohydride solution was added to the solution for reaction. After the reaction was completed, the solid product was separated, washed, dried, and then placed in a reducing atmosphere for thermal reduction treatment. The modified powder was then mixed with polyethylene glycol aqueous solution, granulated, and dried to obtain the catalyst core for later use.

[0007] (2) Titanium dioxide microparticles, low-melting-point glass powder, and binder are mixed to form a slurry. The catalyst core is then placed in the slurry and separated. After drying, a blank with a coating layer on the surface is obtained for later use.

[0008] (3) The blank is heat-treated in an air atmosphere and then cooled to room temperature to obtain the coupling degradation agent.

[0009] Furthermore, in step (1), the calcination temperature is 400~470℃ and the time is 40~50min.

[0010] Further, in step (1), the ratio of the Mg-Al-Fe hydrotalcite powder to the saturated iron ion source solution is 1g: 20~35mL. Optionally, the iron ion source includes at least one of ferric chloride, ferric sulfate, ferric nitrate, etc.

[0011] Furthermore, in step (1), the settling time is 20~30 minutes.

[0012] Further, in step (1), the ratio of the powder to the sodium borohydride solution is 1g:10~15mL. Optionally, the concentration of the sodium borohydride solution is 4~8wt.%.

[0013] Further, in step (1), the reaction time is 20-30 min. Optionally, the drying temperature is 80-120℃ and the time is 45-60 min.

[0014] Further, in step (1), the thermal reduction treatment is performed at a temperature of 800~900℃ for 1~1.5 hours. Optionally, the reducing atmosphere includes any one of hydrogen, carbon monoxide, etc.

[0015] Further, in step (1), the ratio of the modified powder to the polyethylene glycol aqueous solution is 1g:0.19~0.23mL. Optionally, the concentration of the polyethylene glycol aqueous solution is 35~45wt.%.

[0016] Furthermore, in step (1), the drying temperature is 85~100℃ and the time is 1~2 hours.

[0017] Furthermore, in step (1), the particle size of the catalyst core is 3~5 mm.

[0018] Further, in step (2), the ratio of titanium dioxide microparticles, low-melting-point glass powder, and binder is 1g:0.32~0.36g:25~35mL. Optionally, the fineness of the titanium dioxide microparticles is 60~80 mesh.

[0019] Further, in step (2), the adhesive includes at least one of: polyethylene glycol aqueous solution, ethylene glycol aqueous solution, glycerol aqueous solution, etc. Optionally, the concentration of the solution is 35~45 wt.%.

[0020] Further, in step (2), the softening temperature of the low-melting-point glass powder does not exceed 480°C. Optionally, the fineness of the low-melting-point glass powder is 200~250 mesh.

[0021] Furthermore, in step (3), the heat treatment temperature is 430~550℃ and the time is 60~75min.

[0022] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects: The degradation agent of this invention can simultaneously perform photocatalytic and persulfate advanced oxidation coupled degradation of organic matter in aquaculture wastewater, exhibiting high degradation efficiency and good degradation effect. To this end, this invention first uses Mg-Al-Fe hydrotalcite as a raw material, calcining it to retain the layered structure composed of magnesium oxide, aluminum oxide, and iron oxide. Then, after adsorbing an iron ion source between the layers, it is reduced to nano-iron particles distributed in the interlayer using sodium borohydride. Further, this invention subjectes the solid powder obtained after the above treatment to thermal reduction treatment, thereby reducing the iron oxide in the layered structure to elemental iron particles. Simultaneously, the interlayer structure remains stable during the thermal reduction treatment under the support of the nano-iron particles, facilitating the formation of a modified powder that retains its layered characteristics. The elemental iron formed by the iron element conversion and the nano-iron particles together act as a catalyst, catalyzing the release of highly oxidizing free radicals (such as SO42-) from persulfate. - ·OH, ·O2 -This invention utilizes advanced oxidative degradation of organic matter in aquaculture wastewater. Simultaneously, because the catalyst maintains a layered structure, the elemental iron and nano-iron particles within it can more fully contact persulfate, effectively improving the catalytic degradation effect and the utilization rate of persulfate. Furthermore, this invention uses polyethylene glycol to form a core, and then coats its surface with a slurry composed of titanium dioxide particles, low-melting-point glass powder, and a binder, followed by heat treatment. On one hand, the polyethylene glycol in the core and the binder in the coating layer are removed at high temperature, forming a porous structure that facilitates the catalytic degradation of organic matter. On the other hand, the iron element in the core dopes the titanium dioxide, and the elemental iron nano-iron particles in the core can rapidly transfer photogenerated electrons generated by the titanium dioxide in the coating layer, suppressing electron-hole pair recombination, thereby effectively improving the response of titanium dioxide to visible light. This allows the coupled degradation agent obtained by this invention to simultaneously utilize visible light for photocatalytic degradation of organic matter. Furthermore, the coupled degradation agent of this invention can be reused without introducing new pollutants. In addition, the coupling degradation agent of the present invention can be regenerated by undergoing thermal reduction treatment to convert the elemental iron and nano-iron particles into iron oxide after repeated use, which leads to a decrease in efficiency. This overcomes the waste disposal and waste problems caused by catalyst failure. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention and do not constitute an undue limitation of the invention.

[0024] Figure 1 The image shows a sample of the coupling degradation agent prepared in Example 1 below.

[0025] Figure 2 The image shows a sample of the coupling degradation agent prepared in Example 2 below.

[0026] Figure 3 The image shows a sample of the coupling degradation agent prepared in Example 3 below.

[0027] Figure 4 The image shows a sample of the coupling degradation agent prepared in Example 4 below. Detailed Implementation

[0028] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer.

[0029] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as those skilled in the art. The reagents or raw materials used in this invention are readily available through conventional means, and unless otherwise specified, they are used in accordance with conventional methods or product instructions. Furthermore, any methods and materials similar to or equivalent to those described herein can be applied to the methods of this invention. The technical solution of this invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0030] Example 1: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Calcine Mg-Al-Fe hydrotalcite powder at 450℃ for 40 min, then cool to room temperature. Mix the calcined product with saturated ferric nitrate solution at a ratio of 1 g: 30 mL and stir until homogeneous. Let stand for 25 min. After filtering out the solid, add sodium borohydride solution at a ratio of 1 g: 10 mL and react for 25 min. After completion, filter out the solid product, wash with water, then heat to 110℃ and dry for 50 min. Then place it in a carbon monoxide atmosphere and heat to 880℃ for thermal reduction treatment for 1 hour. Then cool to room temperature. Mix the modified powder with polyethylene glycol aqueous solution at a ratio of 1 g: 0.2 mL and stir until homogeneous. Then granulate. Heat the obtained particles to 100℃ and dry for 1 hour to obtain catalyst cores with a particle size distribution between 3 and 5 mm for later use.

[0031] (2) Titanium dioxide particles with a fineness of 60 mesh, low-melting-point glass powder with a softening temperature of 200 mesh (softening temperature between approximately 435 and 452°C), and a polyethylene glycol aqueous solution with a concentration of 40 wt.% are mixed at a ratio of 1 g: 0.35 g: 30 mL and stirred until homogeneous to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a blank with a coating layer on its surface, which is then ready for use.

[0032] (3) The preform is heated to 520°C in air for 75 minutes and then cooled to room temperature to obtain the coupling degradation agent (e.g. Figure 1 (As shown).

[0033] Degradation performance test: The coupling degradation agent prepared in this embodiment was added to aquaculture wastewater (initial organic matter concentration was 206.6 mg / L) from a fish farm at an addition ratio of 3 g / L. Sodium persulfate was then added to the wastewater at a ratio of 0.04 g / L and stirred thoroughly. A xenon lamp was then placed 10 cm above the wastewater as a light source for irradiation (light intensity 1000 W / m²). 2After irradiation for 120 minutes, the concentration of organic matter in the aquaculture effluent was measured again, and the organic matter degradation rate was calculated. The result was 98.19%.

[0034] Example 2: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Calcine Mg-Al-Fe hydrotalcite powder at 400℃ for 50 min, then cool to room temperature. Mix the calcined product with saturated ferric chloride solution at a ratio of 1 g: 20 mL and stir until homogeneous. Let stand for 30 min. After filtering out the solid, add sodium borohydride solution at a ratio of 1 g: 15 mL and react for 30 min. After completion, filter out the solid product, wash with water, then heat to 120℃ and dry for 45 min. Then place it in a hydrogen atmosphere and heat to 800℃ for thermal reduction treatment for 1.5 hours. Then cool to room temperature. Mix the modified powder with polyethylene glycol aqueous solution at a ratio of 1 g: 0.23 mL and stir until homogeneous. Then granulate. Heat the obtained particles to 90℃ and dry for 1.5 hours to obtain catalyst cores with a particle size distribution between 3 and 5 mm for later use.

[0035] (2) Titanium dioxide particles with a fineness of 70 mesh, low-melting-point glass powder with a softening temperature of 250 mesh (softening temperature between approximately 463 and 475°C), and a polyethylene glycol aqueous solution with a concentration of 35 wt.% are mixed at a ratio of 1 g: 0.32 g: 25 mL and stirred evenly to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a green body with a coating layer on its surface, which is then ready for use.

[0036] (3) The preform is heated to 430°C in air for 70 minutes and then cooled to room temperature to obtain the coupling degradation agent (e.g. Figure 2 (As shown).

[0037] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 98.58%.

[0038] Example 3: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Calcine Mg-Al-Fe hydrotalcite powder at 470℃ for 45 min, then cool to room temperature. Mix the calcined product with saturated ferric nitrate solution at a ratio of 1 g: 35 mL and stir until homogeneous. Let stand for 20 min. After filtering out the solid, add 6 wt.% sodium borohydride solution at a ratio of 1 g: 12 mL and react for 20 min. After completion, filter out the solid product, wash with water, then heat to 80℃ and dry for 60 min. Then place it in a carbon monoxide atmosphere and heat to 900℃ for thermal reduction treatment for 1 hour. Then cool to room temperature. Mix the modified powder with 45 wt.% polyethylene glycol aqueous solution at a ratio of 1 g: 0.19 mL and stir until homogeneous. Then granulate. Heat the obtained particles to 85℃ and dry for 2 hours to obtain catalyst cores with a particle size distribution between 3 and 5 mm for later use.

[0039] (2) Titanium dioxide particles with a fineness of 80 mesh, low-melting-point glass powder with a fineness of 200 mesh (softening temperature between approximately 463 and 475°C), and a polyethylene glycol aqueous solution with a concentration of 45 wt.% are mixed at a ratio of 1 g: 0.36 g: 35 mL and stirred evenly to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a green body with a coating layer on its surface, which is then ready for use.

[0040] (3) The preform is heated to 550°C in air for 60 minutes and then cooled to room temperature to obtain the coupling degradation agent (e.g. Figure 3 (As shown).

[0041] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 97.66%.

[0042] Example 4: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Mg-Al-Fe hydrotalcite powder was heated to 450℃ and calcined for 40 min, then cooled to room temperature, and then placed in a carbon monoxide atmosphere and heated to 880℃ for 1 hour for thermal reduction treatment. After cooling to room temperature, the modified powder was mixed with a 40wt.% polyethylene glycol aqueous solution at a ratio of 1g:0.2mL and stirred evenly. Then, it was granulated and the resulting particles were heated to 100℃ and dried for 1 hour to obtain a catalyst core with a particle size distribution between 3 and 5 mm for later use.

[0043] (2) Titanium dioxide particles with a fineness of 60 mesh, low-melting-point glass powder with a softening temperature of 200 mesh (softening temperature between approximately 435 and 452°C), and a polyethylene glycol aqueous solution with a concentration of 40 wt.% are mixed at a ratio of 1 g: 0.35 g: 30 mL and stirred until homogeneous to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a blank with a coating layer on its surface, which is then ready for use.

[0044] (3) The preform is heated to 520°C in air for 75 minutes and then cooled to room temperature to obtain the coupling degradation agent (e.g. Figure 4 (As shown).

[0045] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 85.43%.

[0046] Example 5: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Calcine Mg-Al-Fe hydrotalcite powder at 470℃ for 45 min, then cool to room temperature. Mix the calcined product with saturated ferric nitrate solution at a ratio of 1 g: 35 mL and stir until homogeneous. Let stand for 20 min. After filtering out the solid, add 6 wt.% sodium borohydride solution at a ratio of 1 g: 12 mL and react for 20 min. After completion, filter out the solid product, wash with water, and then heat to 80℃ to dry for 60 min. Mix the modified powder with 45 wt.% polyethylene glycol aqueous solution at a ratio of 1 g: 0.19 mL and stir until homogeneous. Then granulate the mixture and heat the resulting particles to 85℃ to dry for 2 hours to obtain catalyst cores with a particle size distribution between 3 and 5 mm for later use.

[0047] (2) Titanium dioxide particles with a fineness of 80 mesh, low-melting-point glass powder with a fineness of 200 mesh (softening temperature between approximately 463 and 475°C), and a polyethylene glycol aqueous solution with a concentration of 45 wt.% are mixed at a ratio of 1 g: 0.36 g: 35 mL and stirred evenly to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a green body with a coating layer on its surface, which is then ready for use.

[0048] (3) Heat the blank to 550°C in air for 60 minutes and then cool it to room temperature to obtain the coupling degradation agent.

[0049] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 80.16%.

[0050] Example 6: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) The Al-Mg hydrotalcite powder was calcined at 450℃ for 40 min, then cooled to room temperature. The calcined product was mixed with saturated ferric nitrate solution at a ratio of 1 g: 30 mL and stirred until homogeneous. The mixture was then allowed to stand for 25 min. After filtering out the solid, an 8 wt.% sodium borohydride solution was added at a ratio of 1 g: 10 mL and reacted for 25 min. After the reaction was completed, the solid product was filtered out and washed with water. The product was then heated to 110℃ and dried for 50 min. It was then placed in a carbon monoxide atmosphere and heated to 880℃ for 1 hour for thermal reduction treatment. The product was then cooled to room temperature. The modified powder was mixed with a 40 wt.% polyethylene glycol aqueous solution at a ratio of 1 g: 0.2 mL and stirred until homogeneous. The mixture was then granulated. The resulting particles were heated to 100℃ and dried for 1 hour to obtain a catalyst core with a particle size distribution between 3 and 5 mm. The catalyst core was then prepared for use.

[0051] (2) Titanium dioxide particles with a fineness of 60 mesh, low-melting-point glass powder with a softening temperature of 200 mesh (softening temperature between approximately 435 and 452°C), and a polyethylene glycol aqueous solution with a concentration of 40 wt.% are mixed at a ratio of 1 g: 0.35 g: 30 mL and stirred until homogeneous to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a blank with a coating layer on its surface, which is then ready for use.

[0052] (3) Heat the blank to 520°C in air for 75 minutes and then cool it to room temperature to obtain the coupling degradation agent.

[0053] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 82.02%.

[0054] Example 7: A method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, comprising the following steps: (1) Mix Mg-Al-Fe hydrotalcite powder with saturated ferric chloride solution at a ratio of 1g:20mL and stir until homogeneous. Let stand for 30min. After filtering out the solid, add sodium borohydride solution with a concentration of 4wt.% at a ratio of 1g:15mL and react for 30min. After completion, filter out the solid product, wash with water, heat to 120℃ and dry for 45min. Then place it in a hydrogen atmosphere and heat to 800℃ for thermal reduction treatment for 1.5 hours. Then cool to room temperature. Mix the obtained modified powder with polyethylene glycol aqueous solution with a concentration of 35wt.% at a ratio of 1g:0.23mL and stir until homogeneous. Then granulate. Heat the obtained particles to 90℃ and dry for 1.5 hours to obtain catalyst cores with a particle size distribution between 3 and 5mm for later use.

[0055] (2) Titanium dioxide particles with a fineness of 70 mesh, low-melting-point glass powder with a softening temperature of 250 mesh (softening temperature between approximately 463 and 475°C), and a polyethylene glycol aqueous solution with a concentration of 35 wt.% are mixed at a ratio of 1 g: 0.32 g: 25 mL and stirred evenly to form a slurry. The catalyst core is then placed in the slurry to coat its surface with the slurry. The core is then filtered out and dried to obtain a green body with a coating layer on its surface, which is then ready for use.

[0056] (3) Heat the blank to 430°C in air for 70 minutes and then cool it to room temperature to obtain the coupling degradation agent.

[0057] Degradation performance test: The degradation rate of organic matter in fish farming wastewater prepared in this example was tested using the same method as in Example 1 above, and the result was 91.31%.

[0058] The above description is merely a preferred embodiment of the present invention and is 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 method for preparing a photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater, characterized in that, Includes the following steps: (1) After calcining Mg-Al-Fe hydrotalcite powder, it is placed in a saturated iron ion source solution, and after standing, the powder is separated. Sodium borohydride solution is added to it for reaction. After completion, the solid product is separated, washed, dried, and then placed in a reducing atmosphere for thermal reduction treatment. The modified powder is then mixed with polyethylene glycol aqueous solution and granulated. After drying, the catalyst core is obtained and used for later use. (2) Titanium dioxide microparticles, low melting point glass powder and binder are mixed to form a slurry; then the catalyst core is placed in the slurry and then separated, and dried to obtain a blank with a coating layer on the surface for later use; (3) The blank is heat-treated in an air atmosphere and then cooled to room temperature to obtain the coupling degradation agent.

2. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the calcination temperature is 400~470℃ and the time is 40~50min.

3. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the ratio of the Mg-Al-Fe hydrotalcite powder to the saturated iron ion source solution is 1g: 20~35mL; Optionally, in step (1), the iron ion source includes at least one of ferric chloride, ferric sulfate, and ferric nitrate; Optionally, in step (1), the settling time is 20~30 minutes.

4. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the ratio of the powder to the sodium borohydride solution is 1g:10~15mL; optionally, in step (1), the concentration of the sodium borohydride solution is 4~8wt.%.

5. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the reaction time is 20-30 min; optionally, in step (1), the drying temperature is 80-120℃ and the time is 45-60 min.

6. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the temperature of the heat reduction treatment is 800~900℃ and the time is 1~1.5 hours; Optionally, in step (1), the reducing atmosphere includes either hydrogen or carbon monoxide.

7. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (1), the ratio of the modified powder to the polyethylene glycol aqueous solution is 1g: 0.19~0.23mL; Optionally, in step (1), the concentration of the polyethylene glycol aqueous solution is 35~45 wt.%; Optionally, in step (1), the drying temperature is 85~100℃ and the time is 1~2 hours; Optionally, in step (1), the particle size of the catalyst core is 3~5 mm.

8. The preparation method of the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to claim 1, characterized in that, In step (2), the ratio of titanium dioxide microparticles, low melting point glass powder, and binder is 1g:0.32~0.36g:25~35mL; optionally, in step (2), the fineness of the titanium dioxide microparticles is 60~80 mesh.

9. The method for preparing the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to any one of claims 1-8, characterized in that, In step (2), the adhesive comprises at least one of: polyethylene glycol aqueous solution, ethylene glycol aqueous solution, and glycerin aqueous solution; optionally, the concentration of the solution is 35~45 wt.%. Optionally, in step (2), the softening temperature of the low melting point glass powder does not exceed 480°C; Optionally, in step (2), the fineness of the low melting point glass powder is 200~250 mesh.

10. The method for preparing the photocatalytic-persulfate coupled degradation agent for organic matter in aquaculture wastewater according to any one of claims 1-8, characterized in that, In step (3), the heat treatment temperature is 430~550℃ and the time is 60~75min.

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