A method for pretreatment of hydrogen peroxide production wastewater

Abstract

This invention relates to a method for pretreatment of hydrogen peroxide production wastewater, belonging to the field of wastewater treatment technology. The invention uses graphene oxide as a substrate material, with oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl groups attached to its two-dimensional surface, exhibiting good hydrophilicity. Through a complexation reaction between the carboxyl groups on the graphene oxide and soluble iron salts under high-temperature conditions, the iron salts coat the surface, synthesizing graphene-supported nano-ferric oxide particles. This reduces the aggregation of nano-ferric oxide, improves its catalytic effect, and reduces the amount of catalyst required. Furthermore, this invention incorporates sulfonic acid ionic liquids during the synthesis of graphene nano-ferric oxide, introducing sulfonic acid groups into the graphene interlayer and surface. The introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is beneficial for improving the catalytic activity, selectivity, and reaction rate of the nano-ferric oxide, thereby enhancing its catalytic oxidation effect and improving wastewater treatment efficiency.

Description

Technical Field

[0001] This invention relates to a method for pretreatment of hydrogen peroxide production wastewater, belonging to the field of wastewater treatment technology. Background Technology

[0002] Currently, industrial production processes sometimes generate wastewater containing peroxides, the most common being hydrogen peroxide wastewater. Hydrogen peroxide production wastewater is characterized by high concentrations, the presence of recalcitrant heavy aromatics, and unstable water quality and quantity. Most production plants currently employ catalytic oxidation technology combined with other unit technologies to treat anthraquinone process hydrogen peroxide production wastewater. Treatment methods for hydrogen peroxide production wastewater can be divided into two types. One method does not include a biological treatment step. The shortcomings of this method are: ① hydrogen peroxide needs to be added during the catalytic oxidation step; ② the treatment effect is not ideal, and the treated wastewater usually needs to be diluted before discharge. The other method includes a biological treatment step. To ensure the treatment effect of this method, the biodegradability of the wastewater needs to be improved and hydrogen peroxide removed before it enters the biological system. Both of these methods require the addition of nano-Fe3O4 as a catalyst in the catalytic oxidation step. However, nano-Fe3O4 exhibits agglomeration, significantly reducing its surface area and consequently its catalytic activity. Therefore, the dosage is relatively large, resulting in high reagent costs.

[0003] In view of the above-mentioned shortcomings, the designer actively researched and innovated in order to create a pretreatment method for hydrogen peroxide production wastewater, making it more valuable for industrial use. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention aims to provide a method for pretreatment of hydrogen peroxide production wastewater.

[0005] The present invention provides a method for pretreatment of hydrogen peroxide production wastewater, the specific treatment steps of which are as follows:

[0006] (1) The hydrogen peroxide production wastewater to be treated is introduced into the oil separator for oil separation treatment, and then into the flotation tank for flotation treatment to initially remove oil and suspended impurities. The wastewater after flotation treatment is then integrated into the catalytic oxidation reactor with an aeration device at the bottom.

[0007] (2) Add the self-made pretreatment agent to the wastewater in the above catalytic oxidation reactor, and at the same time introduce hydrogen sulfide gas into the catalytic oxidation reactor from the aeration device at the bottom of the reactor. In the reactor, the hydrogen peroxide production wastewater is fully contacted from bottom to top. After the reaction, the waste gas is discharged from the top of the reactor for subsequent treatment. In this way, the wastewater after aeration reaction can be discharged, and the pretreatment of hydrogen peroxide production wastewater can be completed.

[0008] The self-made pretreatment agent is prepared by mixing and reacting ethylene glycol solution, graphene oxide, propylpiperidine bis(trifluoromethanesulfonyl)imide salt, ferric chloride hexahydrate, polyethylene glycol and urea.

[0009] Furthermore, in step (1), the oil separation treatment time is 20-30 minutes, and the air flotation treatment time is 10-15 minutes.

[0010] Furthermore, in step (2), the dosage of the self-made pretreatment agent is 20 mg / L, the gas velocity of hydrogen sulfide gas is 1500 Nm3 / (m2h), and the aeration reaction time is 4 to 6 h.

[0011] Furthermore, the preparation steps of the self-made pretreatment agent are as follows:

[0012] Prepare a 50% ethylene glycol solution. Weigh out 20-30 parts by weight of graphene oxide, 40-50 parts by weight of propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 20-25 parts by weight of ferric chloride hexahydrate, 200-300 parts by weight of polyethylene glycol, and 40-50 parts by weight of urea. Stir and mix for 20-30 minutes, then transfer to a microwave reactor. React at 500W power and 190-200℃ for 1-2 hours. Filter to obtain a filter cake. Place the filter cake in a resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

[0013] Furthermore, the preparation steps of the graphene oxide are as follows:

[0014] Graphite powder, 70% sulfuric acid, and potassium permanganate were mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 2-3 hours. The mixture was then transferred to a water bath at 35°C and reacted for another 1-2 hours. After the reaction, the temperature of the water bath was increased to 60°C and reacted for 15-20 minutes. Then, 150 times the mass of deionized water and 10 times the mass of hydrogen peroxide were added to the mixture. The mixture was stirred for 20-30 minutes and allowed to stand for 1-2 hours to precipitate. The residue was then filtered and dried in an oven at 80-90°C to obtain graphene oxide.

[0015] By means of the above-described solution, the present invention has at least the following advantages:

[0016] (1) This invention uses graphene oxide as the substrate material. Graphene oxide is a layered compound with a much larger interlayer spacing than graphite, obtained by deep liquid-phase oxidation of graphite. It has a large specific surface area and good adsorption performance. At the same time, it has oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl groups on its two-dimensional substrate, which have good hydrophilicity. By complexing the carboxyl groups on graphene oxide with soluble iron salts under high temperature conditions, the iron salts cover its surface, and graphene-supported nano-Fe3O4 particles are synthesized. This can greatly reduce the aggregation of nano-Fe3O4, thereby improving the catalytic effect of nano-Fe3O4 and reducing the amount of catalyst used. In addition, this invention adds sulfonic acid ionic liquid during the synthesis of graphene nano-Fe3O4, introducing sulfonic acid groups into the interlayer and surface of graphene. The introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is beneficial to improving the catalytic activity, selectivity, and reaction rate of nano-Fe3O4, thereby improving its catalytic oxidation effect and wastewater treatment efficiency.

[0017] (2) In the process of mixing wastewater and self-made hydrogen peroxide pretreatment agent, hydrogen sulfide gas is introduced into the wastewater through aeration. During the reaction, nano-ferric oxide reacts with hydrogen peroxide in the wastewater, catalyzing the formation of a large number of hydroxyl radicals. This not only decomposes heavy aromatics in the wastewater and improves its biodegradability, but also rapidly oxidizes hydrogen sulfide into strong acidic substances, lowering the pH value of the wastewater. These acidic substances can "donate" protons or "accept" paired electrons, thereby "combining" with the reactants in the reaction system, changing the reaction rate and selectivity, and promoting the occurrence of catalytic oxidation chemical reactions. This further improves the effect of catalytic oxidation, thereby improving the pretreatment effect of wastewater and enhancing its biodegradability.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in further detail below with reference to the examples. These examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0020] (1) Graphite powder, sulfuric acid with a mass fraction of 70% and potassium permanganate are mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 2-3 hours. Then, the mixture is transferred to a water bath at 35°C and the reaction continues for 1-2 hours. After the reaction, the temperature of the water bath is raised to 60°C and the reaction is carried out for 15-20 minutes. Then, 150 times the mass of deionized water and 10 times the mass of graphite powder are added. After stirring for 20-30 minutes, the mixture is allowed to stand and precipitate for 1-2 hours. After filtration, the residue is separated and dried in an oven at 80-90°C to obtain graphene oxide.

[0021] (2) Prepare a 50% ethylene glycol solution. Weigh 20-30 parts graphene oxide, 40-50 parts propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 20-25 parts ferric chloride hexahydrate, 200-300 parts polyethylene glycol, and 40-50 parts urea by weight. Stir and mix for 20-30 minutes, then transfer to a microwave reactor. React at 500W and 190-200℃ for 1-2 hours. Filter to obtain a filter cake. Place the filter cake in a resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

[0022] This invention uses graphene oxide as the substrate material. Graphene oxide, obtained through deep liquid-phase oxidation of graphite, is a layered compound with a much larger interlayer spacing than graphite, possessing a large specific surface area and excellent adsorption properties. Furthermore, it exhibits good hydrophilicity due to the presence of oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl groups on its two-dimensional basal surface. By allowing the carboxyl groups on graphene oxide to undergo a complexation reaction with soluble iron salts under high-temperature conditions, the iron salts are coated onto the surface, synthesizing graphene-supported nano-Fe3O4 particles. This significantly reduces the aggregation of nano-Fe3O4, thereby improving its catalytic effect and reducing catalyst dosage. In addition, this invention incorporates sulfonic acid ionic liquids during the synthesis of graphene nano-Fe3O4, introducing sulfonic acid groups into the graphene interlayer and surface. The introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is beneficial for improving the catalytic activity, selectivity, and reaction rate of nano-Fe3O4, thus enhancing its catalytic oxidation effect and improving wastewater treatment efficiency.

[0023] (3) The hydrogen peroxide production wastewater to be treated is put into the oil separator for oil separation treatment for 20-30 minutes, and then into the flotation tank for flotation treatment for 10-15 minutes to initially remove oil and suspended impurities. Then the wastewater after flotation treatment is integrated into the catalytic oxidation reactor with aeration device at the bottom.

[0024] (4) Add the self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor at a dosage of 20 mg / L, and at the same time, introduce hydrogen sulfide gas from the aeration device at the bottom of the reactor at a rate of 1500 Nm³. 3 / (m2 The gas is introduced into the catalytic oxidation reactor at a rate of h), and it comes into full contact with the wastewater from bottom to top in the reactor. The waste gas after the reaction is discharged from the top of the reactor for further treatment. After aeration and reaction for 4 to 6 hours, the water is discharged, and the pretreatment of hydrogen peroxide production wastewater is completed.

[0025] In this invention, hydrogen sulfide gas is introduced into the wastewater through aeration during the mixing of wastewater and a self-made hydrogen peroxide pretreatment agent. During the reaction, nano-ferric oxide reacts with hydrogen peroxide in the wastewater, catalytically forming a large number of hydroxyl radicals. This not only decomposes heavy aromatic hydrocarbons in the wastewater, improving its biodegradability, but also rapidly oxidizes the hydrogen sulfide into a strong acid, lowering the pH value of the wastewater. These acidic substances can release protons or accept paired electrons, thus combining with the reactants in the reaction system, altering the reaction rate and selectivity, and promoting the catalytic oxidation reaction. This further enhances the catalytic oxidation effect, thereby improving the wastewater pretreatment effect and its biodegradability.

[0026] Example 1

[0027] (1) Graphite powder, sulfuric acid with a mass fraction of 70% and potassium permanganate were mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 2 hours. Then the mixture was transferred to a water bath at 35°C and the reaction continued for 1 hour. After the reaction, the temperature of the water bath was raised to 60°C and the reaction was carried out for 15 minutes. Then, 150 times the mass of deionized water and 10 times the mass of graphite powder were added. After stirring for 20 minutes, the mixture was allowed to stand and precipitate for 1 hour. After filtration, the residue was separated and dried in an oven at 80°C to obtain graphene oxide.

[0028] (2) Prepare a 50% ethylene glycol solution. Weigh 20 parts graphene oxide, 40 parts propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 20 parts ferric chloride hexahydrate, 200 parts polyethylene glycol, and 40 parts urea by weight. Stir and mix for 20 minutes, then transfer to a microwave reactor. React at 500W and 190℃ for 1 hour. Filter to obtain filter cake. Place the filter cake in an electric resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

[0029] (3) The hydrogen peroxide production wastewater to be treated is put into the oil separator for 20 minutes of oil separation treatment, and then into the flotation tank for 10 minutes of flotation treatment to initially remove oil and suspended impurities. Then the wastewater after flotation treatment is integrated into the catalytic oxidation reactor with aeration device at the bottom.

[0030] (4) Add the self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor at a dosage of 20 mg / L, and at the same time, introduce hydrogen sulfide gas from the aeration device at the bottom of the reactor at a rate of 1500 Nm³. 3 / (m2 The gas flow rate (h) is introduced into the catalytic oxidation reactor, where it comes into full contact with the wastewater from bottom to top. The waste gas after the reaction is discharged from the top of the reactor for further treatment. After 4 hours of aeration and reaction, the wastewater is discharged, thus completing the pretreatment of hydrogen peroxide production wastewater.

[0031] Example 2

[0032] (1) Graphite powder, sulfuric acid with a mass fraction of 70% and potassium permanganate were mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 3 hours. Then the mixture was transferred to a water bath at 35°C and the reaction continued for 2 hours. After the reaction, the temperature of the water bath was increased to 60°C and the reaction was carried out for 18 minutes. Then, 150 times the mass of deionized water and 10 times the mass of graphite powder were added. After stirring for 25 minutes, the mixture was allowed to stand and precipitate for 2 hours. After filtration, the residue was separated and dried in an oven at 85°C to obtain graphene oxide.

[0033] (2) Prepare a 50% ethylene glycol solution. Weigh 25 parts graphene oxide, 45 parts propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 23 parts ferric chloride hexahydrate, 250 parts polyethylene glycol, and 45 parts urea by weight. Stir and mix for 25 minutes, then transfer to a microwave reactor. React at 500W and 195℃ for 2 hours. Filter to obtain filter cake. Place the filter cake in an electric resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

[0034] (3) The hydrogen peroxide production wastewater to be treated is put into the oil separator for 25 minutes and then into the flotation tank for 13 minutes to remove oil and suspended impurities. Then the wastewater after flotation treatment is integrated into the catalytic oxidation reactor with aeration device at the bottom.

[0035] (4) Add the self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor at a dosage of 20 mg / L, and at the same time, introduce hydrogen sulfide gas from the aeration device at the bottom of the reactor at a rate of 1500 Nm³. 3 / (m 2 The gas flow rate (h) is introduced into the catalytic oxidation reactor, where it comes into full contact with the wastewater from bottom to top. The waste gas after the reaction is discharged from the top of the reactor for further treatment. After 5 hours of aeration and reaction, the wastewater is discharged, thus completing the pretreatment of hydrogen peroxide production wastewater.

[0036] Example 3

[0037] (1) Graphite powder, sulfuric acid with a mass fraction of 70% and potassium permanganate were mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 3 hours. Then the mixture was transferred to a water bath at 35°C and the reaction continued for 2 hours. After the reaction, the temperature of the water bath was raised to 60°C and the reaction was carried out for 20 minutes. Then, 150 times the mass of deionized water and 10 times the mass of graphite powder were added. After stirring for 30 minutes, the mixture was allowed to stand and precipitate for 2 hours. After filtration, the residue was separated and dried in an oven at 90°C to obtain graphene oxide.

[0038] (2) Prepare a 50% ethylene glycol solution. Weigh out 30 parts graphene oxide, 50 parts propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 25 parts ferric chloride hexahydrate, 300 parts polyethylene glycol, and 50 parts urea by weight. Stir and mix for 30 minutes, then transfer to a microwave reactor. React at 500W and 200℃ for 2 hours. Filter to obtain a filter cake. Place the filter cake in an electric resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

[0039] (3) The hydrogen peroxide production wastewater to be treated is put into the oil separator for 30 minutes of oil separation treatment, and then into the flotation tank for 15 minutes of flotation treatment to initially remove oil and suspended impurities. Then the wastewater after flotation treatment is integrated into the catalytic oxidation reactor with aeration device at the bottom.

[0040] (4) Add the self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor at a dosage of 20 mg / L, and at the same time, introduce hydrogen sulfide gas from the aeration device at the bottom of the reactor at a rate of 1500 Nm³. 3 / (m 2 The gas flow rate (h) is introduced into the catalytic oxidation reactor, where it comes into full contact with the wastewater from bottom to top. The waste gas after the reaction is discharged from the top of the reactor for further treatment. After 6 hours of aeration and reaction, the wastewater is discharged, thus completing the pretreatment of hydrogen peroxide production wastewater.

[0041] Comparison Example

[0042] Compare with Example 1

[0043] This comparative example is basically the same as Example 1 of the present invention, except that nano-iron oxide is used directly to replace the self-made hydrogen peroxide pretreatment agent of the present invention. Other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is completed in the same way.

[0044] Compare with Example 2

[0045] This comparative example is basically the same as Example 1 of the present invention, except that propylpiperidine bis(trifluoromethanesulfonyl)imide salt is not added when preparing the self-made hydrogen peroxide pretreatment agent. Other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is completed in the same way.

[0046] Compare with Example 3

[0047] This comparative example is basically the same as Example 1 of the present invention, except that hydrogen sulfide gas is not introduced into the catalytic oxidation reactor when treating wastewater. Other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is completed in the same way.

[0048] The treatment effects of Examples 1-3 and Control Examples 1-3 of the present invention were monitored respectively, and the test results are shown in Table 1:

[0049] Detection method:

[0050] Wastewater from hydrogen peroxide production with a COD of 1125 mg / L, a total P of 22.45 mg / L, and a B / C ratio of 0.01 was pretreated using the pretreatment method described in this application, and the parameters of the treated effluent were measured.

[0051] Table 1 Performance Test Results

[0052]

[0053]

[0054] As can be seen from the test data in the table above, the pretreated wastewater in Examples 1-3 of this invention not only significantly reduces the pollutant content in industrial waste gas, but also increases the B / C value after catalytic oxidation, greatly improving the biodegradability of the wastewater. This demonstrates that the technical solution of this application is highly feasible and has excellent treatment effects.

[0055] The performance of Example 1 of the present invention was compared with that of Comparative Examples 1 and 2. In Comparative Example 1, nano-ferric oxide was used directly instead of the self-made hydrogen peroxide pretreatment agent of the present invention, and the other treatment steps remained unchanged, thus completing the pretreatment of hydrogen peroxide production wastewater. In Comparative Example 2, propylpiperidine bis(trifluoromethanesulfonyl)imide salt was not added when preparing the self-made hydrogen peroxide pretreatment agent, and the other treatment steps remained unchanged, thus completing the pretreatment of hydrogen peroxide production wastewater. As a result, after the wastewater of Comparative Example 1 was treated, the removal rate of pollutants in the water was significantly reduced, and the biodegradability of the wastewater was also significantly reduced. After the wastewater of Comparative Example 2 was treated, the removal rate of pollutants in the water was also reduced, and the biodegradability of the wastewater was also reduced, but the degree of reduction was less than that of Comparative Example 1. This can confirm that the present invention uses graphene oxide as the base material. Since graphene oxide is a single-atom or multi-atom layered compound with a much larger interlayer spacing than graphite obtained by deep liquid-phase oxidation of graphite, it has a large specific surface area and good adsorption performance. Meanwhile, it possesses oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl groups on its two-dimensional basal surface, exhibiting good hydrophilicity. By synthesizing graphene-supported nano-Fe3O4 particles through a complexation reaction between the carboxyl groups on graphene oxide and soluble iron salts under high-temperature conditions, the iron salts coat its surface. This significantly reduces the aggregation of nano-Fe3O4, thereby improving its catalytic effect and reducing catalyst dosage. Furthermore, this invention incorporates sulfonic acid-based ionic liquids during the synthesis of graphene nano-Fe3O4, introducing sulfonic acid groups into the graphene interlayer and surface. The introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is beneficial for improving the catalytic activity, selectivity, and reaction rate of nano-Fe3O4, thus enhancing its catalytic oxidation effect and improving wastewater treatment efficiency.

[0056] Next, the performance of Example 1 and Comparative Example 3 of the present invention was compared. In Comparative Example 3, hydrogen sulfide gas was not introduced during wastewater treatment in the catalytic oxidation reactor, while other treatment steps remained unchanged, resulting in a significantly reduced final wastewater treatment effect and minimal improvement in the wastewater's biodegradability. This demonstrates that the present invention introduces hydrogen sulfide gas into the wastewater through aeration during the mixing of wastewater and the self-made hydrogen peroxide pretreatment agent. During the reaction, nano-ferric oxide reacts with hydrogen peroxide in the wastewater, catalyzing the formation of a large number of hydroxyl radicals. This not only decomposes heavy aromatics in the wastewater, improving its biodegradability, but also rapidly oxidizes hydrogen sulfide into a strong acid, lowering the pH value of the wastewater. These acidic substances can release protons or accept paired electrons, thus combining with the reactants in the reaction system, altering the reaction rate and selectivity, and promoting the occurrence of the catalytic oxidation chemical reaction. This further improves the catalytic oxidation effect, thereby enhancing the wastewater pretreatment effect and improving its biodegradability.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for pretreatment of hydrogen peroxide production wastewater, characterized in that: The specific processing steps are as follows: (1) The hydrogen peroxide production wastewater to be treated is introduced into the oil separator for oil separation treatment, and then into the flotation tank for flotation treatment to initially remove oil and suspended impurities. The wastewater after flotation treatment is then integrated into the catalytic oxidation reactor with aeration device at the bottom. (2) Add the self-made pretreatment agent to the wastewater in the above catalytic oxidation reactor, and at the same time, introduce hydrogen sulfide gas into the catalytic oxidation reactor from the aeration device at the bottom of the reactor. In the reactor, the hydrogen peroxide production wastewater is fully contacted from bottom to top. After the reaction, the waste gas is discharged from the top of the reactor for subsequent treatment. In this way, the wastewater after aeration reaction can be discharged, and the pretreatment of hydrogen peroxide production wastewater can be completed. The self-made pretreatment agent is prepared by mixing and reacting ethylene glycol solution, graphene oxide, propylpiperidine bis(trifluoromethanesulfonyl)imide salt, ferric chloride hexahydrate, polyethylene glycol and urea. The preparation steps of the self-made pretreatment agent are as follows: Prepare a 50% ethylene glycol solution. Weigh out 20-30 parts by weight of graphene oxide, 40-50 parts by weight of propylpiperidine bis(trifluoromethanesulfonyl)imide salt, 20-25 parts by weight of ferric chloride hexahydrate, 200-300 parts by weight of polyethylene glycol, and 40-50 parts by weight of urea. Stir and mix for 20-30 minutes, then transfer to a microwave reactor. React at 500W power and 190-200℃ for 1-2 hours. Filter to obtain a filter cake. Place the filter cake in a resistance furnace and react at 200℃ for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

2. The method for pretreatment of hydrogen peroxide production wastewater according to claim 1, characterized in that: In step (1), the oil separation treatment time is 20-30 minutes, and the air flotation treatment time is 10-15 minutes.

3. The method for pretreatment of hydrogen peroxide production wastewater according to claim 1, characterized in that: In step (2), the dosage of the self-made pretreatment agent is 20 mg / L, and the gas velocity of hydrogen sulfide is 1500 Nm. 3 / (m 2 The aeration reaction time is 4 to 6 hours.

4. The method for pretreatment of hydrogen peroxide production wastewater according to claim 1, characterized in that: The preparation steps of the graphene oxide are as follows: Graphite powder, 70% sulfuric acid, and potassium permanganate were mixed in a mass ratio of 1:40:5 and stirred in an ice-water bath for 2-3 hours. The mixture was then transferred to a water bath at 35°C and reacted for another 1-2 hours. After the reaction, the temperature of the water bath was increased to 60°C and reacted for 15-20 minutes. Then, 150 times the mass of deionized water and 10 times the mass of hydrogen peroxide were added to the mixture. The mixture was stirred for 20-30 minutes and allowed to stand for 1-2 hours to precipitate. The residue was then filtered and dried in an oven at 80-90°C to obtain graphene oxide.

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