Composite hydrogel suspension carrier for advanced treatment of recalcitrant organic industrial wastewater and its preparation method

Abstract

This invention relates to a composite hydrogel suspension carrier for the deep treatment of recalcitrant organic industrial wastewater and its preparation method, belonging to the field of polymer composite materials and wastewater treatment. The composite hydrogel suspension carrier of this invention is obtained by immobilizing activated carbon and manganese trioxide in a polyacrylamide hydrogel, followed by foaming with sodium bicarbonate and potential modification with polyquaternary ammonium salt-10. The composite hydrogel suspension carrier of this invention exhibits strong oxidation resistance through the synergistic effect of adsorption and catalytic ozone oxidation, while the use of pore-forming agents and potential modifiers enables rapid enrichment of microorganisms. This provides a specialized carrier with strong oxidation resistance, long-term stability, high degradation efficiency, and economical preparation for the efficient treatment of recalcitrant organic industrial wastewater using a near-field coupling process of catalytic ozone oxidation-biodegradation.

Description

Technical Field

[0001] This invention belongs to the field of polymer composite materials and wastewater treatment technology, specifically relating to a composite hydrogel suspension carrier with adsorption-catalytic ozone oxidation synergistic effect for the deep treatment of recalcitrant organic industrial wastewater and its preparation method. Background Technology

[0002] In recent years, while rapid industrial development has brought economic benefits, it has also generated a large amount of industrial wastewater. If industrial wastewater enters the environment without proper treatment, it poses a serious threat to the aquatic ecosystem and human health; some pollutants can cause poisoning and allergic reactions.

[0003] Catalytic ozone oxidation-biodegradation near-field coupling technology uses a porous carrier as a bridge, cultivating a biofilm within the carrier's pores. The strong oxidizing free radicals generated by catalytic ozone oxidation oxidize recalcitrant pollutants, while the resulting biodegradable intermediates are rapidly utilized and mineralized by microorganisms within the pores. This technology can achieve highly efficient pollutant degradation and deep mineralization when treating recalcitrant industrial wastewater. The porous carrier is the core component enabling this coupling technology. However, commonly used porous carriers, such as polyurethane foam, are primarily used as biological carriers. When faced with ozone oxidation, sponge carriers suffer from limitations such as structural collapse, surface dissolution, and low oxidation resistance. Therefore, improving the carrier's oxidation resistance and its ability to simultaneously catalyze ozone oxidation and protect organisms is crucial for its suitability as a coupling carrier.

[0004] Polyacrylamide hydrogels exhibit good biocompatibility, can firmly adhere to catalysts, and possess tunable morphology. Containing electron-withdrawing carbon groups, the hydrogel structure exhibits a slow reaction rate with ozone, stable structural properties, and high oxidation resistance. Furthermore, it can support a large number of microorganisms, protecting their growth and meeting the carrier requirements for near-field coupling systems of catalytic ozone oxidation and biodegradation, thus demonstrating its potential as a carrier for constructing such systems.

[0005] However, traditional polyacrylamide hydrogels cannot adsorb pollutants, do not have the ability to catalyze ozone oxidation, and the pore structure of un-pore-formed polyacrylamide hydrogels is so small that microorganisms cannot enter and grow and reproduce inside. Summary of the Invention

[0006] This invention aims to solve the technical problems in the prior art by providing a composite hydrogel suspension carrier for the deep treatment of recalcitrant organic industrial wastewater and its preparation method. The composite hydrogel suspension carrier of this invention possesses synergistic adsorption-catalytic ozone oxidation capabilities, and microorganisms can enter the internal structure, thereby enhancing the oxidation resistance, degradation efficiency, and economical preparation of the porous carrier, and achieving a specialized design for the coupled carrier.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0008] A composite hydrogel suspension carrier for the deep treatment of recalcitrant organic industrial wastewater is a composite hydrogel suspension carrier of activated carbon / manganese trioxide / polyacrylamide, wherein activated carbon, manganese trioxide and polyacrylamide are associated through hydrogen bonds.

[0009] More preferably, the composite hydrogel suspension carrier has a sponge-like structure with an average pore size of 44 micrometers.

[0010] A method for preparing a composite hydrogel suspension carrier for the advanced treatment of recalcitrant organic industrial wastewater includes the following steps:

[0011] Step 1: Mix and stir activated carbon and manganese trioxide catalyst with deionized water to obtain a uniform activated carbon / manganese trioxide slurry;

[0012] Step 2: Mix sodium alginate with the activated carbon / manganese trioxide mixed slurry obtained in Step 1. After the sodium alginate is completely dissolved, add acrylamide monomer, crosslinking agent, foaming agent, foam stabilizer and potential modifier while stirring. Stir until a well dispersed precursor suspension is formed. Finally, add catalyst and initiator and polymerize at 40℃-80℃ to obtain activated carbon / manganese trioxide / polyacrylamide composite hydrogel.

[0013] Step 3: Cut the activated carbon / manganese trioxide / polyacrylamide composite hydrogel obtained in Step 2 into cubes, and wash it with ultrasonic and deionized water until all unpolymerized acrylamide monomers are completely removed. Then, swell it to obtain an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier with adsorption and catalytic capabilities.

[0014] More preferably, in step one, the mass ratio of activated carbon to manganese trioxide catalyst is 1:1, and the mass ratio of the total mass of activated carbon and manganese trioxide catalyst to deionized water is 3:10.

[0015] More preferably, in step two, the mass of sodium alginate is 0.2813g.

[0016] In step two, a further optimization is performed.

[0017] The crosslinking agent is N, N 、 - Methylenebisacrylamide, wherein the mass of the crosslinking agent is 0.03 g;

[0018] The catalyst is N, N, N. 、 N 、 -Tetramethylethylenediamine, wherein the volume of the catalyst is 0.4 mL;

[0019] The initiator is sodium persulfate, with a mass fraction of 10 wt% and a volume of 5 mL.

[0020] In a further preferred embodiment, in step two, the foaming agent is sodium bicarbonate, and the mass of the foaming agent is 0.1g-2g. As a more preferred technical solution of the present invention, the mass of the foaming agent is 0.287g.

[0021] More preferably, in step two, the foam stabilizer is sodium dodecyl sulfate, and the mass of the foam stabilizer is 0.1g-0.2g. As a more preferred technical solution of the present invention, the mass of the foam stabilizer is 0.14g.

[0022] Further preferably, as a more preferred technical solution of the present invention, the polymerization temperature is 60°C.

[0023] This invention further adds sodium bicarbonate and sodium dodecyl sulfate to a polyacrylamide composite hydrogel to regulate the pore structure of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel. Sodium bicarbonate is unstable at high temperatures and easily decomposes into sodium carbonate and carbon dioxide. The carbon dioxide escapes from the inside of the hydrogel, forming a porous structure. Adding sodium dodecyl sulfate as a foam stabilizer further increases the porosity of the polyacrylamide composite hydrogel. This prevents microorganisms from suffering oxidative damage within the composite hydrogel under catalytic ozone oxidation conditions and allows the hydrogel to remain suspended in water.

[0024] More preferably, the potential modifier is polyquaternium-10, and the mass of the potential modifier is 0.1g-0.24g. As a more preferred technical solution of the present invention, the mass of the potential modifier is 0.14g.

[0025] This invention adds polyquaternium-10 to an activated carbon / manganese trioxide / polyacrylamide composite hydrogel. By utilizing its positively charged functional groups, the electrophilicity of the composite polyacrylamide hydrogel is increased, thereby accelerating the attachment of microorganisms to the carrier surface.

[0026] The beneficial effects of this invention are:

[0027] 1. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier of the present invention achieves hydrogen bond association between activated carbon, manganese trioxide and polyacrylamide through chemical cross-linking, so that it is firmly adhered to the interior and surface of polyacrylamide hydrogel, and has adsorption and catalytic effects while resisting a certain water erosion, thus avoiding wear and tear during long-term operation.

[0028] 2. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier of the present invention, through the synergistic effect of adsorption and catalytic ozone oxidation, preferentially adsorbs ozone onto the surface of activated carbon and reacts it with the manganese trioxide catalyst for catalytic oxidation, thereby avoiding direct contact between ozone and the polyacrylamide substrate and improving its oxidation resistance.

[0029] 3. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier of the present invention removes pollutants through adsorption while simultaneously catalyzing ozone oxidation to efficiently degrade pollutants located at the adsorption sites, thereby regenerating these sites and achieving a highly efficient adsorption-catalytic oxidation-adsorption-catalytic oxidation cycle. The carrier exhibits high degradation efficiency and long-term stability.

[0030] 4. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier of the present invention, after the pore structure is controlled, has a density close to that of water and can be suspended in water. The suspension carrier is not only conducive to the attachment of extracellular polymers by bacteria and other microorganisms, but also conducive to the renewal and regeneration of biofilm.

[0031] 5. The preparation method of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier of the present invention involves fixing activated carbon and manganese trioxide into a polyacrylamide hydrogel, and using a foaming agent such as sodium bicarbonate and a foaming stabilizer such as sodium dodecyl sulfate to regulate the pore structure of the composite hydrogel. A potential modifier such as polyquaternium-10 is used for modification, utilizing its positively charged functional groups to increase the electrophilicity of the composite polyacrylamide hydrogel, thereby accelerating the attachment of microorganisms to the carrier surface. The composite hydrogel suspension carrier of the present invention is convenient to prepare, has a simple process, and is inexpensive to produce.

[0032] 6. The innovation of this invention lies in the doping of activated carbon and manganese trioxide into polyacrylamide hydrogel to form an activated carbon / manganese trioxide / polyacrylamide composite hydrogel carrier with strong oxidation resistance, which has synergistic effects of adsorption and catalytic ozone oxidation. Attached Figure Description

[0033] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0034] Figure 1 This is an overall morphological image of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1.

[0035] Figure 2 The images show SEM and pore size distribution of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1, where a is an SEM image and b is a pore size distribution image.

[0036] Figure 3The image shows the Fourier transform infrared (FT-IR) spectrum of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1.

[0037] Figure 4 The diagrams show the zeta potentials of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspensions without polyquaternium-10 modification and with polyquaternium-10 modification in Examples 1, 5 and 6.

[0038] Figure 5 This is the compressive stress-strain curve of the polyquaternium-10 modified activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier in Example 1. Detailed Implementation

[0039] The invention is further defined in the following embodiments. Based on the following description and these embodiments, those skilled in the art can determine the basic features of the invention, and various changes and modifications can be made to the invention to make it suitable for various uses and conditions without departing from the nature and scope of the invention.

[0040] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; and the materials and reagents used are commercially available unless otherwise specified.

[0041] Example 1

[0042] The preparation of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier was carried out according to the following steps:

[0043] Step 1: Mix activated carbon and manganese trioxide catalyst at a mass ratio of 1:1, and then mix with deionized water at a mass ratio of 3:10 to form a uniform slurry.

[0044] Step 2: Mechanically stir the homogenate formed in Step 1 at 750 r / min, while adding 0.2813 g of sodium alginate, and stir until completely dissolved;

[0045] Step 3: Add 9g of acrylamide and 0.03g of N,N to the mixed solution from Step 2. 、 Mix methylenebisacrylamide, 0.287g sodium bicarbonate, 0.14g sodium dodecyl sulfate and 0.14g polyquaternium-10, and stir until completely dissolved;

[0046] Step four, add 0.4 mL of N,N,N to the mixture from step three. 、 N 、 - Tetramethylethylenediamine and 5 mL of 10 wt% sodium persulfate were mechanically stirred for 2 min, then poured into a mold and cured at 60°C.

[0047] Step 5: Cut the cured composite polyacrylamide hydrogel into 5mm×5mm cubes as needed, and swell them by ultrasonic soaking in deionized water to obtain an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier.

[0048] Figures 1-5 The images show the physical composition, SEM / pore size distribution, FT-IR, Zeta potential, and compressive stress-strain curve of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension. The physical composition reveals that the composite hydrogel suspension exhibits a sponge-like structure, allowing it to float in water and fluidize under aeration. The SEM / pore size distribution shows an average pore size of 44 micrometers and a maximum pore size of 90 micrometers, which is beneficial for bacterial growth and reproduction within the suspension, avoiding the adverse effects of external ozone oxidation. The FT-IR curve shows that the activated carbon, manganese trioxide, and polyacrylamide hydrogel are bonded by hydrogen bonds, resisting some water erosion. The Zeta potential curve indicates that modification with polyquaternium-10 increases the surface charge of the composite hydrogel suspension, promoting microbial adhesion. Furthermore, the compressive stress-strain curve shows that the modified hydrogel has a fracture stress of 0.26 MPa, meeting practical application requirements.

[0049] Example 2

[0050] Control group. Five groups of polyurethane foams from different manufacturers were used as experimental carriers, with a filling rate of 20% (V). 载体 / V 总 The polyurethane sponge was added to clean water, the pH was maintained at neutral, the temperature was room temperature, the ozone dosage was 14 mg / L, and the aeration flow rate was controlled at 100 mL / min. Under these conditions, the COD content of the polyurethane sponge was monitored for 8 hours. The solution was filtered using a 0.45 micron filter to determine the COD content in the solution. The calculated COD values ​​for the five groups of polyurethane sponge leaching were approximately 25 mg / L, 83 mg / L, 60 mg / L, 48 mg / L, and 57 mg / L, respectively.

[0051] Experimental group. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1 was used as the experimental carrier, with a filling rate of 20% (V). 载体 / V 总 The composite hydrogel suspension was added to clean water, with the pH maintained at neutral and the temperature at room temperature. An ozone dose of 14 mg / L was used, and the aeration flow rate was controlled at 100 mL / min. Under these conditions, the COD content of the dissolved composite hydrogel suspension was monitored over 8 hours. The solution was filtered using a 0.45-micron filter to determine the COD content in the solution, and the calculated COD dissolved from the hydrogel was approximately 8 mg / L.

[0052] By comparing the control group and the experimental group, it can be found that the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier has better oxidation resistance than the polyurethane sponge carrier.

[0053] Example 3

[0054] The application of activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension in the synergistic removal of pollutants through adsorption-catalytic ozone oxidation is carried out according to the following steps:

[0055] Control group. Chlorophenol was used as a characteristic pollutant in industrial wastewater. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1 was used with a filling rate of 20% (V). 载体 / V 总 The chlorophenol solutions were added to 40 mg / L, 60 mg / L, 80 mg / L, 140 mg / L, and 200 mg / L solutions, respectively, at room temperature. Adsorption removal of the chlorophenol solutions was carried out under these conditions for 2.5 hours. The residual concentration of the chlorophenol solutions was measured after filtration using a 0.22-micron filter. The calculated removal rates of chlorophenol by adsorption were approximately 90%, 87%, 84%, 79%, and 76%, respectively.

[0056] Experimental group. Chlorophenol was used as a characteristic pollutant in industrial wastewater. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1 was used with a filling rate of 20% (V 载体 / V 总 Chlorophenol solutions with concentrations of 40 mg / L, 60 mg / L, 80 mg / L, 140 mg / L, and 200 mg / L were added, respectively. The ozone concentration was 14 mg / L, the aeration flow rate was controlled at 100 mL / min, and the temperature was room temperature. Under these conditions, adsorption-catalytic ozone oxidation was performed to degrade the chlorophenol solutions for 2.5 hours. The residual concentration of the chlorophenol solutions was measured using a 0.22-micron filter. The calculated degradation rates of chlorophenol by adsorption-catalytic ozone oxidation were approximately 95%, 94%, 93%, 85%, and 80%, respectively.

[0057] By comparing the control group and the experimental group, it can be found that the synergistic effect of adsorption-catalytic ozone oxidation of activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier in degrading chlorophenol is more efficient than single adsorption removal.

[0058] Example 4

[0059] The application of activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier in long-term pollutant degradation shall be carried out according to the following steps:

[0060] Control group. Chlorophenol was used as a characteristic pollutant in industrial wastewater. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1 was used with a filling rate of 20% (V). 载体 / V 总 The chlorophenol solution was added to a 60 mg / L chlorophenol solution at room temperature. Adsorption was performed to remove the chlorophenol solution under these conditions for 2.5 hours, repeated 5 times. The residual concentration of the chlorophenol solution was measured after filtering the solution using a 0.22 micrometer filter. The removal rates of chlorophenol in each cycle were calculated to be approximately 87%, 76%, 61%, 53%, and 46%.

[0061] Experimental group. Chlorophenol was used as a characteristic pollutant in industrial wastewater. The activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension prepared in Example 1 was used with a filling rate of 20% (V 载体 / V 总 The chlorophenol solution was added to a 60 mg / L chlorophenol solution, with an ozone dose of 14 mg / L, an aeration flow rate of 100 mL / min, and room temperature. Under these conditions, the chlorophenol solution was degraded by adsorption-catalytic ozone oxidation for 2.5 h, repeated 5 times. The residual concentration of the chlorophenol solution was measured by filtering the solution using a 0.22 micrometer filter. The degradation rates of chlorophenol by adsorption-catalytic ozone oxidation in each cycle were calculated to be approximately 94%, 87%, 80%, 73%, and 73%, respectively.

[0062] By comparing the control group and the experimental group, it can be found that the synergistic effect of adsorption-catalytic ozone oxidation of activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier in degrading chlorophenol is more stable than that of single adsorption removal.

[0063] Example 5

[0064] The preparation of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier was carried out according to the following steps:

[0065] Step 1: Mix activated carbon and manganese trioxide catalyst at a mass ratio of 1:1, and then mix with deionized water at a mass ratio of 3:10 to form a uniform slurry.

[0066] Step 2: Mechanically stir the homogenate formed in Step 1 at 750 r / min, while adding 0.2813 g of sodium alginate, and stir until completely dissolved;

[0067] Step 3: Add 9g of acrylamide and 0.03g of N,N to the mixed solution from Step 2. 、 Mix methylenebisacrylamide, 0.287g sodium bicarbonate, 0.14g sodium dodecyl sulfate and 0.04g polyquaternium-10, and stir until completely dissolved;

[0068] Step four, add 0.4 mL of N,N,N to the mixture from step three. 、 N 、 - Tetramethylethylenediamine and 5 mL of 10 wt% sodium persulfate were mechanically stirred for 2 min, then poured into a mold and cured at 60°C.

[0069] Step 5: Cut the cured composite polyacrylamide hydrogel into 5mm×5mm cubes as needed, and swell them by ultrasonic soaking in deionized water to obtain an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier.

[0070] Example 6

[0071] The preparation of the activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier was carried out according to the following steps:

[0072] Step 1: Mix activated carbon and manganese trioxide catalyst at a mass ratio of 1:1, and then mix with deionized water at a mass ratio of 3:10 to form a uniform slurry.

[0073] Step 2: Mechanically stir the homogenate formed in Step 1 at 750 r / min, while adding 0.2813 g of sodium alginate, and stir until completely dissolved;

[0074] Step 3: Add 9g of acrylamide and 0.03g of N,N to the mixed solution from Step 2. 、 Mix methylenebisacrylamide, 0.287g sodium bicarbonate, 0.14g sodium dodecyl sulfate and 0.24g polyquaternium-10, and stir until completely dissolved;

[0075] Step four, add 0.4 mL of N,N,N to the mixture from step three. 、 N 、 -Tetramethylethylenediamine and 5 mL sodium persulfate were mechanically stirred for 2 minutes, then poured into a mold and cured at 60°C.

[0076] Step 5: Cut the cured composite polyacrylamide hydrogel into 5mm×5mm cubes as needed, and swell them by ultrasonic soaking in deionized water to obtain an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier.

[0077] Compared to Example 1, Examples 5 and 6 maintained the same preparation conditions except for the amount of polyquaternium-10 added. The change in zeta of the prepared activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension was used as the evaluation criterion. The zeta of the suspension in Example 1 was -15.03 mV, while the zetas in Examples 5 and 6 were -17.03 mV and -19.17 mV, respectively. This indicates that within the scope of this invention, zeta is positively correlated with the zeta modifier, depending on the amount of polyquaternium-10 added, but there is an upper limit to the amount added.

[0078] The above embodiments mainly describe a preferred solution of the present invention, including the basic operating steps and main features of the present invention. Those skilled in the art should have a certain understanding of these embodiments. The present invention is not limited to the above embodiments. The above embodiments and descriptions in the specification all illustrate the principle of the present invention. Various changes and modifications can be made without departing from the principle of the present invention, and all such changes and modifications fall within the protection scope of the present invention.

[0079] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a composite hydrogel suspended carrier for advanced treatment of recalcitrant organic industrial wastewater, characterized by, The method comprises the following steps: Step one: mix activated carbon and manganese trioxide catalyst with deionized water and stir to obtain a uniform activated carbon / manganese trioxide mixed slurry; Step two: mix sodium alginate with the activated carbon / manganese trioxide mixed slurry obtained in step one and stir until the sodium alginate is completely dissolved, then add acrylamide polymer monomer, crosslinking agent, foaming agent, foam stabilizer and potential modifier under stirring, and stir until a well-dispersed precursor suspension is formed; finally, add catalyst and initiator, and polymerize at 40-80°C to obtain activated carbon / manganese trioxide / polyacrylamide composite hydrogel; Step three: cut the activated carbon / manganese trioxide / polyacrylamide composite hydrogel prepared in step two into cubes, clean with ultrasonic and deionized water until the un-polymerized acrylamide polymer monomer is completely removed, and then swell to obtain an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier with adsorption and catalytic capacity; In step two: The foaming agent is sodium bicarbonate; The foam stabilizer is sodium dodecyl sulfate; The potential modifier is polyquaternary ammonium salt-10.

2. The method for preparing a composite hydrogel suspended carrier for advanced treatment of recalcitrant organic industrial wastewater according to claim 1, characterized in that, In step one, the mass ratio of activated carbon to manganese trioxide catalyst is 1:1, and the total mass of activated carbon and manganese trioxide catalyst to the mass of deionized water is 3:

10.

3. The method for preparing a composite hydrogel suspended carrier for advanced treatment of recalcitrant organic industrial wastewater according to claim 1, characterized in that, In step two, the mass of sodium alginate is 0.2813g.

4. The method for preparing a composite hydrogel suspended carrier for advanced treatment of non-biodegradable organic industrial wastewater according to claim 1, characterized in that, In step two, The crosslinking agent is N,N 、 - methylenebisacrylamide, the mass of the crosslinking agent being 0.03 g; The catalyst is N,N,N 、 , N 、 -tetramethylethylenediamine, the volume of the catalyst being 0.4 mL; The initiator is sodium persulfate, the mass fraction of the initiator is 10wt%, and the volume is 5mL.

5. The method for preparing the composite hydrogel suspended carrier for advanced treatment of the recalcitrant organic industrial wastewater according to claim 1, characterized in that, In step two, the mass of the foaming agent is 0.1g-2g.

6. The method for preparing a composite hydrogel suspended carrier for advanced treatment of non-biodegradable organic industrial wastewater according to claim 1, characterized in that, In step two, the mass of the foam stabilizer is 0.1g-0.2g.

7. The method for preparing a composite hydrogel suspended carrier for advanced treatment of non-biodegradable organic industrial wastewater according to claim 1, characterized in that, The polymerization temperature is 60°C.

8. The method for preparing a composite hydrogel suspended carrier for advanced treatment of recalcitrant organic industrial wastewater according to claim 1, characterized in that, The mass of the potential modifier is 0.1g-0.24g.

9. A composite hydrogel suspension carrier for advanced treatment of refractory organic industrial wastewater, prepared by the preparation method of any one of claims 1-8, which is an activated carbon / manganese trioxide / polyacrylamide composite hydrogel suspension carrier, wherein activated carbon, manganese trioxide and polyacrylamide are associated through hydrogen bonds.

10. The composite hydrogel suspended carrier for advanced treatment of recalcitrant organic industrial wastewater according to claim 9, characterized in that, The composite hydrogel suspension carrier has a sponge-like structure with an average pore size of 44 microns.

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