Preparation method and use of an iron-zinc nano-microsphere microelectrolysis composite material

Abstract

The present invention belongs to the technical field of water treatment, and specifically relates to a preparation method and application of an iron-zinc nano-microsphere micro-electrolysis composite material. The preparation method first prepares iron-zinc compound nano-microspheres by a solvothermal method, then obtains relatively pure nano-metal oxides after high-temperature calcination, and then mixes it with appropriate proportions of iron powder, modified activated carbon, borax, sodium-based bentonite and pore-forming agent with water, compresses and forms, and after drying, high-temperature sintering is carried out under an oxygen-free negative pressure condition to obtain the iron-zinc nano-microsphere micro-electrolysis composite material. Trace amounts of zinc oxide in the material are reduced to elemental zinc protective layers, which can effectively reduce the oxidation of iron and improve the chemical corrosion resistance of the material surface. This micro-electrolysis material has high catalytic performance and is suitable for the treatment of various industrial wastewaters such as electroplating, chemical industry, printing and dyeing, leather, and pharmaceuticals, and can significantly improve the biodegradability of the wastewater.

Description

Technical Field

[0001] The present invention belongs to the microelectrolysis technology in the field of wastewater treatment. Specifically, it relates to a preparation method and use of an iron-zinc nano-sphere microelectrolysis composite material. Background Art

[0002] The microelectrolysis technology is a catalytic reduction water treatment technology, which can break the molecular chains of benzene rings, condensed rings, and long-chain organic compounds, change the chemical bonds of molecular groups, thereby reducing the toxicity of organic pollutants and improving the biodegradability of wastewater. This technology has been widely used in the treatment of high-concentration and difficult-to-degrade industrial wastewater. In addition, this technology can also be combined with hydrogen peroxide to form a microelectrolysis-Fenton system, which can efficiently remove various pollutant indicators such as COD, ammonia nitrogen, chromaticity, and SS.

[0003] Domestic scholars have done a lot of work on the preparation process of microelectrolysis composite materials. For example, the Chinese patent document "Preparation and Application of a Core-Shell Iron-Carbon Microelectrolysis Material High-Efficiency Fenton Catalyst" with the publication number CN109179594A prepares an Fe-Pd MOFs material with a graphitized carbon shell and zero-valent iron to prepare a microelectrolysis composite material. The carbon shell protects the hydrolyzed iron ions from attaching to the surface, and the palladium in the inner core promotes the conversion of Fe 2+ and Fe 3+ The catalyst has good durability and stability, but the structure of the MOFs material prepared by mechanical grinding cannot be strictly controlled, which affects the macroscale preparation efficiency of the material. The Chinese patent document "A Nano-Micro Combined Iron-Based Bimetallic Microelectrolysis Material" with the publication number CN110643981A discloses that a displacement complex plating metal is used to cover the surface of the iron-based material, increasing the number of primary batteries on the surface of the plating metal and the iron-based material, and improving the catalytic performance of microelectrolysis. However, the conditions for displacement complex plating are relatively harsh. Summary of the Invention

[0004] One of the purposes of the present invention is to provide a preparation method of an iron-zinc nano-sphere microelectrolysis composite material. In the iron-zinc nano-sphere microelectrolysis composite material prepared by this method, trace zinc oxide is reduced to a zinc single-element protective layer, which can effectively reduce the oxidation of iron, improve the chemical corrosion resistance of the material surface, and at the same time has high catalytic performance, and is suitable for the treatment of various industrial wastewaters such as electroplating, chemical industry, printing and dyeing, leather, and pharmaceutical industries, and can significantly improve the biodegradability of wastewater.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A preparation method of an iron-zinc nano-sphere microelectrolysis composite material, comprising the following steps:

[0006] (1) Weigh zinc acetate, iron acetylacetonate, and terephthalic acid in a molar ratio of 1:1:2, add them to a sufficient amount of organic solvent until they are evenly dispersed, and obtain a mixed solution after ultrasonic dispersion and dissolution. The mixed solution undergoes a solvothermal synthesis reaction, and the product is then washed, dried, and calcined at a low temperature to obtain iron-zinc nanospheres;

[0007] (2) Weigh activated carbon powder, soak it in a modification solution and combine it with ozone treatment to obtain modified activated carbon powder;

[0008] (3) Mix the iron-zinc nanospheres prepared in step (1), the modified activated carbon powder prepared in step (2), borax, sodium-based bentonite, iron powder, and pore-forming agent in a mass ratio of (10-20):(10-20):(3-8):2:(50-70):1, press them into shape and dry, then calcine them at a high temperature under oxygen-free conditions and cool to obtain a copper-cerium bimetallic oxide ozone catalyst;

[0009] Among them, steps (1) and (2) have no sequential order.

[0010] As a further improvement to the preparation method of the iron-zinc nanosphere microelectrolysis composite material:

[0011] Preferably, the organic solvent in step (1) is composed of N,N-dimethylformamide (DMF) and pure water mixed in a volume ratio of 8:1, or composed of dimethylacetamide (DMAC) and pure water mixed in a volume ratio of 8:1.

[0012] Preferably, the solvothermal synthesis reaction in step (1) is carried out in a reaction kettle with a polytetrafluoroethylene liner, the reaction temperature is 150-160 °C, and the reaction time is 3-4 h.

[0013] Preferably, the low-temperature calcination in step (1) is carried out in a tubular furnace under argon protection, the heating rate of calcination is 3-5 °C / min, the calcination temperature is 500-600 °C, and the calcination time is 1-2 h.

[0014] Preferably, the modification solution in step (2) is nitric acid with a concentration of 5-20 wt%, sulfuric acid with a concentration of 5-20 wt%, or an aqueous sodium hydroxide solution with a concentration of 5-20 wt%. The soaking and combined ozone treatment time is 4-6 h, and the ozone treatment method is to introduce ozone gas into the modification solution, and the flow rate of introduction is 0.1-0.2 L / min.

[0015] Preferably, the high-temperature calcination temperature in step (3) is 1100-1300 °C, the heating rate is 3-5 °C / min, the calcination time is 2-4 h, and the negative pressure in the furnace chamber during calcination is -0.1 to -0.3 Mpa.

[0016] Preferably, in step (3), the method of pressing and forming is hydraulic pressing or pneumatic pressing, and the pressure is 2 - 5 bar.

[0017] Preferably, in step (3), the cooling method is quenching, and the quenching medium is pure water or 1 - 3 wt% sodium chloride or 1 - 3 wt% sodium hydroxide solution.

[0018] Preferably, the pore - forming agent in step (3) is one or a mixture of two or more of oxalic acid, sodium carbonate, and calcium carbonate.

[0019] The second object of the present invention is to provide the use of the iron - zinc nano - microsphere micro - electrolysis composite material prepared by the above - mentioned preparation method in treating high - concentration organic industrial wastewater.

[0020] The beneficial effects of the present invention compared with the prior art are as follows:

[0021] 1) The present invention provides a preparation method of an iron - zinc nano - microsphere micro - electrolysis composite material. This preparation method first prepares iron - zinc compound nano - microspheres by a solvothermal method, then obtains relatively pure nano - metal oxides after high - temperature calcination, and then mixes them with appropriate proportions of iron powder, modified activated carbon powder, borax, sodium - based bentonite, and pore - forming agent with water and mixes them evenly, presses and forms, dries, and then conducts high - temperature sintering under an anaerobic negative - pressure condition to obtain the iron - zinc nano - microsphere micro - electrolysis composite material. Among them, in step (1), the preparation of the iron - zinc nano - microsphere catalytic component can increase the surface area of the material, which will improve the electron transfer efficiency of the material; in step (2), the combined treatment of the modified solution and ozone is used to modify the activated carbon, which can enhance the surface acidic oxygen - containing groups, such as carboxyl groups, hydroxyl groups, lactone groups, etc., thereby reducing the surface energy, increasing the surface active groups of the material, and improving the hydrophilicity; in step (3), pressing and forming the material is conducive to industrial application, and quenching is used to improve the toughness and strength of the alloy material.

[0022] 2) The micro - electrolysis material prepared by the present invention has a high specific surface area. Based on the relatively large specific surface area of the iron - zinc nano - microsphere material, the incorporation of nano - microspheres can significantly increase the contact area between the iron - carbon composite material and pollutants, and improve the reaction efficiency.

[0023] 3) The micro - electrolysis material prepared by the present invention has a certain corrosion resistance. The iron - zinc nano - oxides are partially reduced at high temperatures and form zinc wrapped in iron - carbon after calcination. The potential of zinc is relatively low, which can reduce the corrosion degree of iron. At the same time, the incorporation of iron - zinc microspheres changes the potential difference of the material, promotes the diffusion of the material's oxide film, and enhances the corrosion - resistant performance of the material.

[0024] 4) The micro - electrolysis material prepared by the present invention has high catalytic performance and is suitable for the treatment of various industrial wastewaters such as electroplating, chemical industry, printing and dyeing, leather, and pharmaceutical industries, and can significantly improve the biodegradability of wastewater. Description of the Drawings

[0025] Figure 1 To scan the SEM spectrum of the iron-zinc nano-oxide microspheres prepared in Example 1 using a FEI-Quanta 200 type scanning electron microscope (SEM).

[0026] Figure 2 To scan the TEM spectrum of the iron-zinc nano-oxide microspheres prepared in Example 1 using a Tecnai G2 F20 type transmission scanning electron microscope (TEM).

[0027] Figure 3 To obtain the energy spectrum of the iron-zinc nano-oxide microspheres prepared in Example 1.

[0028] Figure 4 To obtain the mapping diagram of the electrolytic composite material of the iron-zinc nano-microspheres prepared in Example 1.

[0029] Figure 5 To obtain the BET and pore size distribution diagrams of the electrolytic composite material of the iron-zinc nano-microspheres prepared in Example 1.

[0030] Figure 6 To obtain the XPS total spectrum of the electrolytic composite material of the iron-zinc nano-microspheres prepared in Example 1.

[0031] Figure 7 Cyclic test diagram of the electrolytic composite material of the iron-zinc nano-microspheres prepared in Example 1 for treating high-concentration organic wastewater;

[0032] Figure 8 Total iron leaching concentration diagram of the electrolytic composite material of the iron-zinc nano-microspheres prepared in Example 1 tested under the conditions of pH 4.5 and a filler dosage of 20 g / L. Detailed implementation method

[0033] The present invention will be further described below in conjunction with specific embodiments, but the substantial content of the present invention is not limited to the following embodiments. The methods are conventional methods unless otherwise specified, and the materials can be obtained from public commercial channels unless otherwise specified. Those skilled in the art should know that any simple transformation or substitution based on the substantial content of the present invention belongs to the protection scope required by the present invention.

[0034] Example 1

[0035] This example provides a preparation method of an electrolytic composite material of iron-zinc nano-microspheres, including the following steps:

[0036] (1) Preparation of iron-zinc nanoparticles. Weigh 2.2 g of zinc acetate dihydrate, 3.5 g of ferric acetylacetonate, and 3.3 g of terephthalic acid in a molar ratio of 1:1:2, and add them to 400 mL of an organic solvent in sequence. The organic solvent is prepared by mixing DMAC and water in a ratio of 8:1, and fully dispersed by ultrasonication to obtain a mixed solution. The mixed solution is transferred to a polytetrafluoroethylene reactor and reacted at 150°C for 4 h. The product is washed with anhydrous ethanol, dried in vacuum, and then transferred to a 500°C tube furnace for calcination. The product is fully protected by argon gas at 40 mL / min and calcined for 1 h. The product is ground and sieved for use. Repeat the above steps to prepare several grams of iron-zinc nanoparticles.

[0037] (2) Modification of activated carbon. Weigh a certain amount of activated carbon powder, soak it in a 10wt% sulfuric acid solution and treat it with ozone. The ozone flow rate is 0.1L / min and the treatment time is 4h to obtain modified activated carbon powder.

[0038] (3) Preparation of iron-zinc nano-microsphere electrolytic composite material. Weigh 18g of the iron-zinc nano-microspheres prepared in step (1), 11g of modified activated carbon powder, 3g of borax, 2g of sodium bentonite, 65g of zero-valent iron powder, and 1g of sodium carbonate, add water and mix, and then press and form with a hydraulic press to form a cube shape. After vacuum drying at 60°C for 24h at a pressure of 3bar, transfer to a pit furnace and sinter at a high temperature of 1300°C. During the sintering process, the negative pressure in the furnace is -0.3Mpa. The sintering time is 2h, and the mixture is placed in pure water for quenching and cooling to room temperature to form an iron-zinc nano-microsphere electrolytic composite material.

[0039] The SEM spectrum of the iron-zinc nano-oxide microspheres prepared in step (1) was scanned using a FEI-Quanta 200 scanning electron microscope (SEM). Figure 1 As shown by Figure 1 It can be seen that the surface morphology of the material is mainly composed of closely arranged microspheres at the nanometer level, and the distribution is relatively uniform. The size of each microsphere is 40-50nm.

[0040] The TEM spectrum of the iron-zinc oxide nanospheres prepared in step (1) was scanned using a Tecnai G2 F20 transmission scanning electron microscope (TEM). Figure 2 As shown, from the transmission image, it can be seen that a single microsphere is composed of multiple tiny nanoparticles.

[0041] Figure 3 The energy spectrum of the iron-zinc nano-oxide microspheres obtained in the above step (1) can intuitively analyze the material composition as follows: the main elements are Fe, Zn, C, and O, with the proportion of Fe being 16% and the proportion of Zn being 4.49%.

[0042] Figure 4It is the mapping diagram of the iron-zinc nano-oxide microspheres prepared in the above step (1). It can be seen that the Fe, Zn, and O elements are evenly distributed.

[0043] Figure 5 It is the BET and pore size distribution diagram of the iron-zinc nano-oxide microspheres prepared in the above step (1). It can be seen that the average pore size of the material is The BET area is 13.8752 m 2 / g, N 2 The adsorption-desorption curve presents a type-IV isotherm and an H3-type hysteresis loop, indicating the presence of a mesoporous structure in the catalyst.

[0044] Figure 6 It is the XPS survey spectrum of the iron-zinc nano-oxide microspheres prepared in the above step (1). From the XPS survey spectrum, it can be seen that the elements Fe, Zn, C, and O exist in the material.

[0045] Take about 100 g of the iron-zinc nano-microsphere microelectrolysis composite material prepared in step (3). The appearance is a cube with a side length of 2 cm. The measured crushing strength is 1200 - 1300 N. Take 100 g of the prepared microelectrolysis material and apply it in a microelectrolysis pilot test device as a strengthening pretreatment material for chemical industrial wastewater. Place it in the microelectrolysis pilot test device. The treatment capacity is 3 - 5 L / d, and the hydraulic retention time is 30 min, which is controlled by the inlet peristaltic pump. The inlet COD is 6000 - 6500 mg / L, and the outlet drops to 3000 - 3300 mg / L. The B / C increases from 0.05 - 0.1 to 0.2 - 0.3, and the biodegradability is significantly improved. The remaining COD can be fully degraded by microorganisms in the subsequent stage.

[0046] Figure 7 It is the cyclic test diagram of the iron-zinc nano-microsphere electrolysis composite material prepared in Example 1 when used for treating high-concentration organic wastewater; from Figure 7 It can be seen that the iron-zinc nano-microelectrolysis material is relatively stable during application. In a high-concentration organic wastewater environment, after 5 cyclic tests, the removal rate of organic matter is still 68%.

[0047] Figure 8 It is the total iron leaching concentration diagram of the iron-zinc nano-microsphere electrolysis composite material prepared in Example 1 at pH 4.5 and a filler dosage of 20 g / L; from Figure 8 It can be seen that due to the presence of the iron-zinc nano-microspheres, under acidic conditions, the zinc protective layer in the material reduces the potential difference, which can effectively reduce the oxidation of iron and improve the chemical corrosion resistance of the material surface.

[0048] Example 2

[0049] This example provides a preparation method of an iron-zinc nano-microsphere microelectrolysis composite material, including the following steps:

[0050] (1) Preparation of iron-zinc nanoparticles. Weigh 3.3 g of zinc acetate dihydrate, 5.25 g of ferric acetylacetonate, and 4.95 g of terephthalic acid in a molar ratio of 1:1:2, and add them to 600 mL of an organic solvent in sequence. The organic solvent is prepared by mixing DMAC and water in a ratio of 8:1, and fully dispersed by ultrasonication to obtain a mixed solution. The mixed solution is transferred to a polytetrafluoroethylene reactor and reacted at 150°C for 3 h. The product is washed with anhydrous ethanol, dried in vacuum, and then transferred to a 500°C tube furnace for calcination. The product is fully protected by argon gas at 50 mL / min and calcined for 1 h. The product is ground and sieved for use. Repeat the above steps to prepare several grams of iron-zinc nanoparticles.

[0051] (2) Modification of activated carbon. Weigh a certain amount of activated carbon powder, soak it in a 15wt% nitric acid solution and treat it with ozone. The ozone flow rate is 0.2L / min, and the treatment time is 5h to obtain modified activated carbon powder.

[0052] (3) Preparation of iron-zinc nano-microsphere electrolytic composite material. Weigh 15g of the iron-zinc nano-microspheres prepared in step (1), 17g of modified activated carbon powder, 5g of borax, 2g of sodium bentonite, 60g of zero-valent iron powder, and 1g of sodium carbonate, add water and mix, and then press and form into blocks with a side length of 2cm using a hydraulic press. After vacuum drying at 60°C for 24h at a pressure of 4bar, transfer to a pit furnace and sinter at a high temperature of 1200°C. During the sintering process, the negative pressure in the furnace is -0.3Mpa, and the sintering time is 2h to form an iron-zinc nano-microsphere electrolytic composite material.

[0053] Take about 100g of the iron-zinc nano-microsphere micro-electrolysis composite material prepared in step (3), which looks like a cube with a side length of 2cm. The crushing strength is measured to be 1000-1100N. Take 100g of the prepared micro-electrolysis material and apply it to a micro-electrolysis pilot device as a micro-electrolysis pretreatment material for pharmaceutical wastewater. The micro-electrolysis pilot device has a processing capacity of 3-5L / d and a hydraulic retention time of 30min, which is controlled by an inlet peristaltic pump. The inlet COD is 9000-10000mg / L, and the outlet water is reduced to 4200-4500mg / L. The B / C increases from 0.05-0.1 to 0.2-0.25, and the biodegradability is significantly improved. The remaining COD can be fully degraded by microorganisms in the later stage.

[0054] Example 3

[0055] This embodiment provides a method for preparing an iron-zinc nano-microsphere micro-electrolysis composite material, comprising the following steps:

[0056] (1) Preparation of iron-zinc nanoparticles. Weigh 4.4 g zinc acetate dihydrate, 7.0 g ferric acetylacetonate, and 6.6 g terephthalic acid in a molar ratio of 1:1:2, and add them to 800 mL of an organic solvent in sequence. The organic solvent is prepared by mixing DMAC and water in a ratio of 8:1, and fully dispersed by ultrasonication to obtain a mixed solution. The mixed solution is transferred to a polytetrafluoroethylene reactor and reacted at 150°C for 2 h. The product is washed with anhydrous ethanol, dried in vacuum, and then transferred to a 500°C tube furnace for calcination. The product is fully protected by argon gas at 30 mL / min and calcined for 1 h. The product is ground and sieved for use. Repeat the above steps to prepare several grams of iron-zinc nanoparticles.

[0057] (2) Modification of activated carbon. Weigh a certain amount of activated carbon powder, soak it in a 20wt% sodium hydroxide solution and treat it with ozone. The ozone flow rate is 0.2L / min, and the treatment time is 6h to obtain modified activated carbon powder;

[0058] (3) Preparation of iron-zinc nano-microsphere electrolytic composite material. Weigh 10 g of the iron-zinc nano-microspheres prepared in step (1), 15 g of modified activated carbon powder, 3 g of borax, 2 g of sodium-based bentonite, 70 g of zero-valent iron powder, and 1 g of sodium carbonate, add water and mix, and then press and form into a 2 cm square using a hydraulic press. After vacuum drying at 60°C for 24 h at a pressure of 5 bar, transfer to a pit furnace and sinter at a high temperature of 1300°C. During the sintering process, the negative pressure in the furnace is -0.3 MPa. The sintering time is 1 h to form an iron-zinc nano-microsphere electrolytic composite material.

[0059] Take about 100g of the iron-zinc nano-microsphere micro-electrolysis composite material prepared in step (3), and measure the crushing strength of 1200-1300N. Take 100g of the prepared micro-electrolysis material and apply it in a micro-electrolysis pilot device as a reinforced pretreatment material for printing and dyeing wastewater. Place it in a micro-electrolysis pilot device with a processing capacity of 3-5L / d and a hydraulic retention time of 30min, which is controlled by an inlet peristaltic pump. The raw water COD is reduced from 17000-17500mg / L, the effluent COD is reduced to 9600-10500mg / L, the B / C is increased from 0.03-0.05 to 0.15-0.2, and the biodegradability is significantly improved.

[0060] As the proportion of iron-zinc microsphere catalytic components in the composite filler increases, the pretreatment effect on organic industrial wastewater is obvious, the wastewater treatment efficiency is increased, the COD degradation rate is also increased, and the biodegradability of the effluent is improved. From the above cases, it can be concluded that the bimetallic microspheres in the composite material can synergistically degrade pollutants by combining valence state conversion, electron transfer, and redox in the micro-electrolysis system.

[0061] Those skilled in the art should understand that the above are only several specific embodiments of the present invention, rather than all embodiments. It should be noted that many variations and improvements can be made by those of ordinary skill in the art, and all variations or improvements that do not exceed the scope described in the claims should be regarded as the protection scope of the present invention.

Claims

1. A preparation method of an iron-zinc nano-microsphere microelectrolysis composite material, characterized in that, it includes the following steps: (1) Weigh zinc acetate, iron acetylacetonate and terephthalic acid with a molar ratio of 1:1:2, add them to an organic solvent until evenly dispersed, and obtain a mixed solution after ultrasonic dispersion and dissolution. The mixed solution undergoes a solvothermal synthesis reaction, and the product is then washed, dried and calcined. The calcination is carried out in a tubular furnace under argon protection. The heating rate of the calcination is 3-5 °C / min, the calcination temperature is 500-600 °C, and the calcination time is 1-2 h to obtain iron-zinc nano-microspheres. The solvothermal synthesis reaction is carried out in a reaction kettle with a polytetrafluoroethylene lining. The reaction temperature is 150-160 °C, and the reaction time is 3-4 h; (2) Weigh activated carbon powder, soak it in a modification solution and combine it with ozone treatment to obtain modified activated carbon powder; the modification solution is nitric acid with a concentration of 5-20 wt%, sulfuric acid with a concentration of 5-20 wt%, or sodium hydroxide aqueous solution with a concentration of 5-20 wt%. The soaking and combined ozone treatment time is 4-6 h. The ozone treatment method is to introduce ozone gas into the modification solution, and the flow rate of introduction is 0.1-0.2 L / min; (3) Mix the iron-zinc nano-microspheres prepared in step (1), the modified activated carbon powder prepared in step (2), borax, sodium-based bentonite, iron powder, and pore-forming agent according to the mass ratio of (10-20):(10-20):(3-8):2:(50-70):1, then press and form and dry, and calcine at high temperature under oxygen-free conditions and then cool to obtain the iron-zinc nano-microsphere microelectrolysis composite material; wherein steps (1) and (2) have no sequential order.

2. The preparation method of the iron-zinc nano-microsphere microelectrolysis composite material according to claim 1, characterized in that, the organic solvent in step (1) is composed of N,N-dimethylformamide (DMF) and pure water mixed according to a volume ratio of 8:1, or composed of dimethylacetamide (DMAC) and pure water mixed according to a volume ratio of 8:

1.

3. The preparation method of the iron-zinc nano-microsphere microelectrolysis composite material according to claim 1, characterized in that, the high-temperature calcination temperature in step (3) is 1100-1300 °C, the heating rate is 3-5 °C / min, the calcination time is 2-4 h, and the negative pressure in the furnace during the sintering process is -0.1 to -0.3 Mpa.

4. The preparation method of the iron-zinc nano-microsphere microelectrolysis composite material according to claim 1, characterized in that, the method of pressing and forming in step (3) is hydraulic pressing or pneumatic pressing, and the pressure is 2-5 bar.

5. The preparation method of the iron-zinc nano-microsphere microelectrolysis composite material according to claim 1, characterized in that, the cooling method in step (3) is quenching cooling, and the quenching medium is pure water or 1-3 wt% sodium chloride or 1-3 wt% sodium hydroxide solution.

6. The preparation method of the iron-zinc nano-microsphere microelectrolysis composite material according to claim 1, characterized in that, the pore-forming agent in step (3) is one or a mixture of two or more of oxalic acid, sodium carbonate, and calcium carbonate.

7. Use of the iron-zinc nano microsphere microelectrolysis composite material prepared by the preparation method according to any one of claims 1-6 in treating high-concentration organic industrial wastewater.

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