Hydrogen peroxide production wastewater pretreatment method

Abstract

The invention relates to a hydrogen peroxide production wastewater pretreatment method, and belongs to the technical field of wastewater treatment. The graphene oxide is used as a substrate material, some oxygen-containing functional groups such as hydroxyl, epoxy group and carboxyl are connected to the two-dimensional base plane of the graphene oxide, and the hydrophilicity is good. Carboxyl on graphene oxide and soluble ferric salt are subjected to a complex reaction under the high-temperature condition, the ferric salt covers the surface of the graphene oxide, graphene-loaded nano ferroferric oxide particles are synthesized, the agglomeration effect of nano ferroferric oxide can be reduced, the catalytic effect of nano ferroferric oxide is improved, the dosage of a catalyst is reduced, and the cost is reduced. In addition, a sulfonic acid-based ionic liquid is added in the process of synthesizing graphene nano ferroferric oxide, sulfonic acid groups are introduced into interlayers and the surface of graphene, and the introduction of the sulfonic acid groups increases the number of acidic active centers on the surface of the graphene, so that the catalytic activity, the selectivity and the reaction rate of the nano ferroferric oxide are improved; the catalytic oxidation effect is improved, and the wastewater treatment efficiency is improved.

Description

Technical Field

[0001] The invention relates to a method for pretreating wastewater from hydrogen peroxide production, and belongs to the technical field of wastewater treatment. Background Art

[0002] At present, in the process of industrial production, a kind of wastewater containing peroxide is sometimes produced, among which the most common is wastewater containing hydrogen peroxide. The wastewater produced by hydrogen peroxide has the characteristics of high concentration, contains difficult-to-degrade heavy aromatic hydrocarbons, and has unstable water quality and quantity. At present, most production plants use catalytic oxidation technology combined with other unit technologies to treat anthraquinone method hydrogen peroxide production wastewater. There are two methods for treating hydrogen peroxide production wastewater. One method does not include a biochemical treatment step. The disadvantages of this method are that ① hydrogen peroxide needs to be added in the catalytic oxidation step, and ② the effect of treating wastewater is not ideal. Usually, the treated wastewater needs to be diluted before it can be discharged. Another method includes a biochemical treatment step. In order to ensure the treatment effect of this method, it is necessary to improve the biodegradability of the wastewater and remove hydrogen peroxide in the wastewater before the wastewater enters the biochemical system. Both of the above methods require the addition of nano-Fe3O4 as a catalyst in the catalytic oxidation step, but nano-Fe3O4 has agglomeration, which greatly reduces its surface area, thereby causing its catalytic activity to decrease. Therefore, the dosage is relatively large and the cost of the agent is high.

[0003] In view of the above-mentioned defects, the designers have actively carried out research and innovation in order to create a method for pretreatment of hydrogen peroxide production wastewater to make it more valuable for industrial use. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a method for pretreating hydrogen peroxide production wastewater.

[0005] A method for pretreating hydrogen peroxide production wastewater of the present invention comprises the following specific treatment steps:

[0006] (1) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for oil separation treatment, and then placed in a flotation tank for flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after flotation treatment is placed in a catalytic oxidation reactor with an aeration device at the bottom;

[0007] (2) adding a self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor, and at the same time passing hydrogen sulfide gas from the aeration device at the bottom of the reactor into the catalytic oxidation reactor, so that hydrogen sulfide gas fully contacts with the wastewater from bottom to top in the reactor, and the waste gas after the reaction is discharged from the top of the reactor for subsequent treatment, so that the water discharged after the aeration reaction can complete the pretreatment of the hydrogen peroxide production wastewater;

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

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

[0011] Furthermore, the preparation steps of the homemade pretreatment agent are:

[0012] A 50% ethylene glycol solution is prepared, and 20 to 30 parts of graphene oxide, 40 to 50 parts of propylpiperidinium bistrifluoromethanesulfonimide salt, 20 to 25 parts of ferric chloride hexahydrate, 200 to 300 parts of polyethylene glycol, and 40 to 50 parts of urea are weighed by weight. The mixture is stirred for 20 to 30 minutes, and then transferred into a microwave reactor. After reacting for 1 to 2 hours at a power of 500 W and a temperature of 190 to 200° C., a filter cake is obtained by filtration and separation. The filter cake is placed in a resistance furnace and reacted at 200° C. for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

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

[0014] Graphite powder, 70% sulfuric acid and potassium permanganate are mixed in a mass ratio of 1:40:5, stirred for 2 to 3 hours in an ice water bath, and then transferred to a 35°C water bath to continue reacting for 1 to 2 hours. After the reaction, the water bath temperature is increased to 60°C and reacted for 15 to 20 minutes. Deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder are added, stirred for 20 to 30 minutes, allowed to settle for 1 to 2 hours, filtered and separated to obtain a filter residue, and placed in an oven to dry at 80 to 90°C to obtain graphene oxide.

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

[0016] (1) The present invention uses graphene oxide as a substrate material. Since graphene oxide is a single-atom or multi-atom layered compound with a much larger interlayer distance 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, some oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl are connected to its two-dimensional base surface, and it has good hydrophilicity. The carboxyl groups on the graphene oxide react with soluble iron salts under high temperature conditions to cover the iron salts on its surface, and the synthetic graphene-loaded nano-iron tetroxide particles can greatly reduce the agglomeration of nano-iron tetroxide, thereby improving the catalytic effect of nano-iron tetroxide and reducing the amount of catalyst. In addition, the present invention adds sulfonic acid ionic liquids in the process of synthesizing graphene nano-iron tetroxide, introduces sulfonic acid groups between graphene layers and on the surface, and the introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is beneficial to the improvement of the catalytic activity and selectivity of nano-iron tetroxide and the reaction rate, improves its catalytic oxidation effect, and improves the 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 by aeration. During the reaction, nano-iron tetroxide reacts with hydrogen peroxide in the wastewater to form a large number of hydroxyl radicals by oxidation catalysis, which can not only decompose heavy aromatic hydrocarbons in the wastewater and improve the biodegradability of the wastewater, but also quickly oxidize hydrogen sulfide into strong acidic substances and reduce the pH value of the wastewater. These acidic substances can "dispense" protons or "receive" paired electrons, thereby "combining" with reactants in the reaction system, changing the reaction rate and selectivity, and promoting the occurrence of catalytic oxidation chemical reactions. The effect of catalytic oxidation is further improved, thereby improving the wastewater pretreatment effect and improving its biodegradability.

[0018] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail as follows. DETAILED DESCRIPTION

[0019] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0020] (1) mixing graphite powder, 70% sulfuric acid and potassium permanganate in a mass ratio of 1:40:5, stirring the mixture in an ice water bath for 2 to 3 hours, and then transferring the mixture to a 35° C. water bath to continue reacting for 1 to 2 hours. After the reaction, raising the temperature of the water bath to 60° C. to react for 15 to 20 minutes, adding deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder, stirring the mixture for 20 to 30 minutes, allowing the mixture to settle for 1 to 2 hours, and filtering and separating the residue, and drying the residue in an oven at 80 to 90° C. to obtain graphene oxide;

[0021] (2) preparing a 50% ethylene glycol solution, weighing 20 to 30 parts of graphene oxide, 40 to 50 parts of propylpiperidinium bistrifluoromethanesulfonyl imide salt, 20 to 25 parts of ferric chloride hexahydrate, 200 to 300 parts of polyethylene glycol, and 40 to 50 parts of urea, stirring and mixing for 20 to 30 minutes, transferring to a microwave reactor, reacting at a power of 500 W and a temperature of 190 to 200° C. for 1 to 2 hours, filtering and separating to obtain a filter cake, placing the filter cake in a resistance furnace, and reacting at 200° C. for 20 hours to obtain a homemade hydrogen peroxide pretreatment agent;

[0022] The present invention uses graphene oxide as a substrate material. Since graphene oxide is a single-atom or multi-atom layered compound with a much larger interlayer distance 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, some oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl are connected to its two-dimensional base surface, and it has good hydrophilicity. The carboxyl groups on the graphene oxide react with soluble iron salts under high temperature conditions to cover the iron salts on its surface, and the synthetic graphene-loaded nano-iron tetroxide particles can greatly reduce the agglomeration of nano-iron tetroxide, thereby improving the catalytic effect of nano-iron tetroxide and reducing the amount of catalyst. In addition, the present invention adds sulfonic acid ionic liquids in the process of synthesizing graphene nano-iron tetroxide, introduces sulfonic acid groups between graphene layers and on the surface, and the introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is conducive to the improvement of the catalytic activity and selectivity of nano-iron tetroxide and the reaction rate, improves its catalytic oxidation effect, and improves the wastewater treatment efficiency;

[0023] (3) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for 20 to 30 minutes of oil separation treatment, and then placed in an air flotation tank for 10 to 15 minutes of air flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after air flotation treatment is introduced into a catalytic oxidation reactor with an aeration device at the bottom;

[0024] (4) A self-made pretreatment agent was added to the wastewater in the above catalytic oxidation reactor at a dosage of 20 mg / L, and hydrogen sulfide gas was simultaneously aerated at 1500 Nm / s from the aeration device at the bottom of the reactor. 3 / (m2 h) is passed into the catalytic oxidation reactor at a gas rate of 1.5 to 2.0 g / cm2, and is fully contacted 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 subsequent treatment. After 4 to 6 hours of aeration reaction, the water is discharged, and the pretreatment of the hydrogen peroxide production wastewater is completed.

[0025] In the process of mixing wastewater and self-made hydrogen peroxide pretreatment agent, hydrogen sulfide gas is introduced into the wastewater by aeration. During the reaction, nano-ferroferric oxide reacts with hydrogen peroxide in the wastewater to form a large number of hydroxyl radicals by oxidation catalysis, which can not only decompose heavy aromatic hydrocarbons in the wastewater and improve the biodegradability of the wastewater, but also quickly oxidize hydrogen sulfide into strong acidic substances to reduce the pH value of the wastewater. These acidic substances can "dispense" protons or "receive" paired electrons, thereby "combining" with reactants in the reaction system, changing the reaction rate and selectivity, and promoting the occurrence of catalytic oxidation chemical reactions. The effect of catalytic oxidation is further improved, thereby improving the wastewater pretreatment effect and improving its biodegradability.

[0026] Example 1

[0027] (1) Graphite powder, 70% sulfuric acid and potassium permanganate were mixed in a mass ratio of 1:40:5, stirred in an ice water bath for 2 h, and then transferred to a 35° C. water bath to continue the reaction for 1 h. After the reaction, the water bath temperature was raised to 60° C. for 15 min, and then deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder were added. After stirring for 20 min, the mixture was allowed to stand for 1 h, filtered and separated to obtain a residue, and placed in an oven for drying at 80° C. to obtain graphene oxide;

[0028] (2) Prepare a 50% ethylene glycol solution, weigh 20 parts of graphene oxide, 40 parts of propylpiperidinium bis(trifluoromethanesulfonyl)imide salt, 20 parts of ferric chloride hexahydrate, 200 parts of polyethylene glycol, and 40 parts of urea, stir and mix for 20 minutes, transfer to a microwave reactor, react at a power of 500 W and a temperature of 190° C. for 1 hour, filter and separate to obtain a filter cake, place the filter cake in a resistance furnace, and react at 200° C. for 20 hours to obtain a homemade hydrogen peroxide pretreatment agent;

[0029] (3) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for 20 minutes of oil separation treatment, and then placed in a flotation tank for 10 minutes of flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after flotation treatment is introduced into a catalytic oxidation reactor with an aeration device at the bottom;

[0030] (4) A self-made pretreatment agent was added to the wastewater in the above catalytic oxidation reactor at a dosage of 20 mg / L, and hydrogen sulfide gas was simultaneously aerated at 1500 Nm / s from the aeration device at the bottom of the reactor. 3 / (m2 h) is passed into the catalytic oxidation reactor at a gas rate of 1.5 to 2.5 % and the wastewater is fully contacted 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 subsequent treatment. After 4 hours of aeration reaction, the water is discharged, and the pretreatment of the hydrogen peroxide production wastewater can be completed.

[0031] Example 2

[0032] (1) 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 3 h, then transferred to a 35° C. water bath and continued to react for 2 h. After the reaction, the water bath temperature was raised to 60° C. and reacted for 18 min. Deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder were added. After stirring for 25 min, the mixture was allowed to stand for 2 h and filtered to obtain a residue, which was then placed in an oven and dried at 85° C. to obtain graphene oxide;

[0033] (2) Prepare a 50% ethylene glycol solution, weigh 25 parts of graphene oxide, 45 parts of propylpiperidinium bistrifluoromethanesulfonyl imide salt, 23 parts of ferric chloride hexahydrate, 250 parts of polyethylene glycol, and 45 parts of urea, stir and mix for 25 minutes, transfer to a microwave reactor, react at a power of 500 W and a temperature of 195° C. for 2 hours, filter and separate to obtain a filter cake, place the filter cake in a resistance furnace, and react at 200° C. for 20 hours to obtain a homemade hydrogen peroxide pretreatment agent;

[0034] (3) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for 25 minutes of oil separation treatment, and then placed in a flotation tank for 13 minutes of flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after flotation treatment is introduced into a catalytic oxidation reactor with an aeration device at the bottom;

[0035] (4) A self-made pretreatment agent was added to the wastewater in the above catalytic oxidation reactor at a dosage of 20 mg / L, and hydrogen sulfide gas was simultaneously aerated at 1500 Nm / s from the aeration device at the bottom of the reactor. 3 / (m 2 h) is passed into the catalytic oxidation reactor at a gas rate of 1.5 gas / kg / min, and is fully contacted 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 subsequent treatment. After 5 hours of aeration reaction, the water is discharged, and the pretreatment of the hydrogen peroxide production wastewater is completed.

[0036] Example 3

[0037] (1) 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 3 h, then transferred to a 35° C. water bath and continued to react for 2 h. After the reaction, the water bath temperature was raised to 60° C. and reacted for 20 min. Deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder were added. After stirring for 30 min, the mixture was allowed to stand for 2 h and filtered to obtain a residue, which was then placed in an oven and dried at 90° C. to obtain graphene oxide;

[0038] (2) Prepare a 50% ethylene glycol solution, weigh 30 parts of graphene oxide, 50 parts of propylpiperidinium bis(trifluoromethanesulfonyl)imide salt, 25 parts of ferric chloride hexahydrate, 300 parts of polyethylene glycol, and 50 parts of urea, stir and mix for 30 minutes, transfer to a microwave reactor, react at a power of 500 W and a temperature of 200° C. for 2 hours, filter and separate to obtain a filter cake, place the filter cake in a resistance furnace, and react at 200° C. for 20 hours to obtain a homemade hydrogen peroxide pretreatment agent;

[0039] (3) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for 30 minutes of oil separation treatment, and then placed in a flotation tank for 15 minutes of flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after flotation treatment is introduced into a catalytic oxidation reactor with an aeration device at the bottom;

[0040] (4) A self-made pretreatment agent was added to the wastewater in the above catalytic oxidation reactor at a dosage of 20 mg / L, and hydrogen sulfide gas was simultaneously aerated at 1500 Nm / s from the aeration device at the bottom of the reactor. 3 / (m 2 h) is passed into the catalytic oxidation reactor at a gas rate of 1.5 to 2.5 % and the wastewater is fully contacted 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 subsequent treatment. After 6 hours of aeration reaction, the water is discharged, and the pretreatment of the hydrogen peroxide production wastewater can be completed.

[0041] Comparison Example

[0042] Comparative Example 1

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

[0044] Comparative Example 2

[0045] This comparative example is basically the same as Example 1 of the present invention, except that propylpiperidinium bistrifluoromethanesulfonyl imide salt is not added when preparing the homemade hydrogen peroxide pretreatment agent, and the other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is also completed;

[0046] Comparative Example 3

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

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

[0049] Detection method:

[0050] Take hydrogen peroxide production wastewater with a COD of 1125 mg / L, a total P of 22.45 mg / L, and a B / C of 0.01, pretreat it using the pretreatment method of the present application, and detect the effluent parameters after treatment.

[0051] Table 1 Performance test results

[0052]

[0053]

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

[0055] The performance of Example 1 of the present invention is compared with that of Reference Example 1 and Reference Example 2. Since Reference Example 1 directly uses nano-ferroferric oxide to replace the homemade hydrogen peroxide pretreatment agent of the present invention, other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is also completed; when preparing the homemade hydrogen peroxide pretreatment agent in Reference Example 2, propylpiperidinium bistrifluoromethanesulfonyl imide salt is not added, and other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is also completed; as a result, after the wastewater of Reference Example 1 is treated, the pollutant removal rate in the water is significantly reduced, and the biodegradability of the sewage is also significantly reduced, while after the wastewater of Reference Example 2 is treated, the pollutant removal rate in the water is also reduced, and the biodegradability of the sewage is also reduced, but the degree of reduction is less than that of Reference Example 1, which can confirm that the present invention uses graphene oxide as a substrate material, because graphene oxide is a single-atom or multi-atom layered compound with an interlayer spacing much larger than that of graphite obtained by deep liquid phase oxidation of graphite, and has a large specific surface area and good adsorption performance. At the same time, some oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl are connected to its two-dimensional base surface, and the hydrophilicity is good. The carboxyl groups on the graphene oxide react with soluble iron salts under high temperature conditions to cover the iron salts on its surface, and the graphene-loaded nano-iron tetroxide particles are synthesized, which can greatly reduce the agglomeration of nano-iron tetroxide, thereby improving the catalytic effect of nano-iron tetroxide and reducing the amount of catalyst. In addition, the present invention adds sulfonic acid ionic liquids in the process of synthesizing graphene nano-iron tetroxide, introduces sulfonic acid groups between graphene layers and on the surface, and the introduction of sulfonic acid groups increases the number of acidic active centers on the graphene surface, which is conducive to the improvement of the catalytic activity and selectivity of nano-iron tetroxide and the reaction rate, improves its catalytic oxidation effect, and improves the wastewater treatment efficiency;

[0056] Then, the performance of Example 1 of the present invention and Reference Example 3 are compared. Since Reference Example 3 does not introduce hydrogen sulfide gas through aeration when treating wastewater in a catalytic oxidation reactor, other treatment steps remain unchanged, and the pretreatment of hydrogen peroxide production wastewater is also completed; the final wastewater treatment effect is also significantly reduced, and the improvement of the biodegradability of the wastewater is not obvious. It can be confirmed that in the process of mixing wastewater and a homemade hydrogen peroxide pretreatment agent, the present invention introduces hydrogen sulfide gas into the wastewater by aeration. During the reaction process, nano-iron tetroxide reacts with hydrogen peroxide in the wastewater, and oxidative catalysis forms a large number of hydroxyl radicals, which can not only decompose heavy aromatic hydrocarbons in the wastewater and improve the biodegradability of the wastewater, but also quickly oxidize hydrogen sulfide into strongly acidic substances, reduce the pH value of the wastewater, and these acidic substances can "put" out protons or "receive" paired electrons, thereby "combining" with reactants in the reaction system, changing the reaction rate and selectivity, and promoting the occurrence of catalytic oxidation chemical reactions. The effect of catalytic oxidation is further improved, thereby improving the wastewater pretreatment effect and improving its biodegradability.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for pretreating wastewater from hydrogen peroxide production, characterized in that: The specific processing steps are: (1) The hydrogen peroxide production wastewater to be treated is placed in a grease trap for oil separation treatment, and then placed in a flotation tank for flotation treatment to preliminarily remove oil and suspended impurities, and then the wastewater after flotation treatment is placed in a catalytic oxidation reactor with an aeration device at the bottom; (2) adding a self-made pretreatment agent to the wastewater in the above-mentioned catalytic oxidation reactor, and at the same time passing hydrogen sulfide gas from the aeration device at the bottom of the reactor into the catalytic oxidation reactor, so that hydrogen sulfide gas fully contacts with the wastewater from bottom to top in the reactor, and the waste gas after the reaction is discharged from the top of the reactor for subsequent treatment, so that the water discharged after the aeration reaction can complete the pretreatment of the hydrogen peroxide production wastewater; The self-made pretreatment agent is prepared by mixed reaction of ethylene glycol solution, graphene oxide, propylpiperidinium bis(trifluoromethanesulfonyl)imide salt, ferric chloride hexahydrate, polyethylene glycol and urea.

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

3. A method for pretreating 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 the hydrogen sulfide gas is 1500 Nm 3 / (m 2 h), the aeration reaction time is 4 to 6 hours.

4. A method for pretreating hydrogen peroxide production wastewater according to claim 1, characterized in that: The preparation steps of the self-made pretreatment agent are: A 50% ethylene glycol solution is prepared, and 20 to 30 parts of graphene oxide, 40 to 50 parts of propylpiperidinium bistrifluoromethanesulfonimide salt, 20 to 25 parts of ferric chloride hexahydrate, 200 to 300 parts of polyethylene glycol, and 40 to 50 parts of urea are weighed by weight. The mixture is stirred for 20 to 30 minutes, and then transferred into a microwave reactor. After reacting for 1 to 2 hours at a power of 500 W and a temperature of 190 to 200° C., a filter cake is obtained by filtration and separation. The filter cake is placed in a resistance furnace and reacted at 200° C. for 20 hours to obtain a self-made hydrogen peroxide pretreatment agent.

5. A method for pretreating hydrogen peroxide production wastewater according to claim 1, characterized in that: The preparation steps of the graphene oxide are: Graphite powder, 70% sulfuric acid and potassium permanganate are mixed in a mass ratio of 1:40:5, stirred for 2 to 3 hours in an ice water bath, and then transferred to a 35°C water bath to continue reacting for 1 to 2 hours. After the reaction, the water bath temperature is increased to 60°C and reacted for 15 to 20 minutes. Deionized water 150 times the mass of the graphite powder and hydrogen peroxide 10 times the mass of the graphite powder are added, stirred for 20 to 30 minutes, allowed to settle for 1 to 2 hours, filtered and separated to obtain a filter residue, and placed in an oven to dry at 80 to 90°C to obtain graphene oxide.

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