Fenton catalyst as well as preparation method and application thereof

Abstract

The invention provides a preparation method of a Fenton catalyst, which comprises the following steps: kneading iron-containing minerals, copper-containing minerals and optional adsorption components and / or matrixes for forming, and then roasting. The invention also provides application of the Fenton catalyst obtained by the preparation method in wastewater treatment. When being used for treating DMSO wastewater, the Fenton catalyst has the advantages of simple process, low cost, high treatment depth and zero emission.

Description

Technical Field

[0001] The invention belongs to the field of catalysts, and specifically relates to a Fenton catalyst and a preparation method thereof, as well as an application thereof in industrial wastewater treatment, especially in advanced oxidation treatment of DMSO-containing wastewater. Background Art

[0002] Dimethyl sulfoxide (DMSO) is widely used as an intermediate or solvent in the fields of pharmaceuticals, chemicals, electrical components, etc. However, the residual dimethyl sulfoxide in the wastewater during the production process is easily converted into harmful substances such as hydrogen sulfide and sulfide in natural water bodies, causing harm to the environment. In addition, organic wastewater containing DMSO is difficult to biodegrade, with a BOD5 / COD ratio of only 0.035 and poor biodegradability, so the treatment effect of conventional biological methods is not ideal.

[0003] At present, the treatment of DMSO wastewater mainly includes distillation and biological methods. In the production process of dimethyl sulfoxide, most of the dimethyl sulfoxide is recovered through vacuum distillation to obtain a high-purity product, but the residual bottom liquid and the wastewater from cleaning oxidation towers, vacuum distillation towers and other equipment still contain a certain concentration of dimethyl sulfoxide. Since the wastewater contains various impurities such as inorganic salts and the concentration of dimethyl sulfoxide is low, it is very difficult and costly to recover dimethyl sulfoxide in the wastewater. Therefore, most dimethyl sulfoxide production companies do not recycle and directly discharge the wastewater containing dimethyl sulfoxide to wastewater treatment facilities. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a method for treating DMSO wastewater by thermally enhanced Fenton oxidation and achieving standard reuse. The method activates the heterogeneous Fenton catalyst by heating, and has the characteristics of simple process, low cost, high treatment depth, and zero emission.

[0005] In order to achieve the above object, the present invention provides the following technical solutions.

[0006] In a first aspect, the present invention provides a method for preparing a Fenton catalyst, comprising kneading a mixture containing an iron-containing mineral and a copper-containing mineral and optionally an adsorption component and / or a matrix into a mold, and then calcining the mixture.

[0007] In some embodiments, the iron-containing mineral includes at least one of hematite, limonite, crucible clay or iron mud. In some embodiments, the iron mud comes from the blast furnace ironmaking process and refers to impurities with a relatively high iron content, and its main components are ferroferric oxide and ferrous oxide.

[0008] In some embodiments, the copper-containing mineral includes at least one of cuprite, malachite, azurite, and chrysocolla.

[0009] In some embodiments, the molar ratio of the Fe element in the iron-containing mineral to the Cu element in the copper-containing mineral is (0.5-5): 1, for example, 0.5: 1, 1: 1, 2: 1, 3: 1, 4: 1, 5: 1 or any value therebetween. In some preferred embodiments, the molar ratio of the Fe element in the iron-containing mineral to the Cu element in the copper-containing mineral is (1-2): 1, for example, 1: 1, 1.2: 1, 1.4: 1, 1.6: 1, 1.8: 1, 2: 1 or any value therebetween.

[0010] In some embodiments, the content of the Fe element is 0.5wt%-5wt%, for example, 0.5wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt% or any value therebetween, based on the total amount of the iron-containing mineral and the copper-containing mineral.

[0011] In some embodiments, the adsorption component is selected from molecular sieves, preferably selected from at least one of phosphate aluminum molecular sieves or silicon aluminum molecular sieves, and more preferably selected from at least one of beta molecular sieves, Y-type molecular sieves, mordenite, MCM-22, MCM-41, SAPO-34 or SAPO-5. In the Fenton catalyst of the present application, the adsorption component is used to enrich pollutants such as DMSO, thereby improving the degradation ability.

[0012] In some embodiments, the matrix is ​​selected from at least one of attapulgite, diatomaceous earth, bentonite, or kaolin.

[0013] In some embodiments, the mass ratio of the adsorbent component to the matrix is ​​(0.05-5): 1, for example, 0.1: 1, 0.5: 1, 1: 1, 2: 1, 3: 1, 4: 1, 5: 1 or any value therebetween. In some preferred embodiments, the mass ratio of the adsorbent component to the matrix is ​​(0.1-0.8): 1, for example, 0.1: 1, 0.2: 1, 0.3: 1, 0.4: 1, 0.5: 1, 0.6: 1, 0.7: 1, 0.8: 1 or any value therebetween.

[0014] In some embodiments, the mixture further includes a molding agent.

[0015] In some embodiments, the molding agent includes cellulose and / or sesbania powder.

[0016] In some embodiments, the mass ratio of the molding agent to the matrix is ​​(0.02-0.5): 1, for example, 0.02: 1, 0.025: 1, 0.05: 1, 0.1: 1, 0.2: 1, 0.3: 1, 0.4: 1, 0.5: 1 or any value therebetween. In some preferred embodiments, the mass ratio of the molding agent to the matrix is ​​(0.05-0.2): 1.

[0017] In a second aspect, the present invention provides a Fenton catalyst prepared by the preparation method described in the first aspect, wherein the Fenton catalyst comprises an iron-containing oxide and a copper-containing oxide.

[0018] In some embodiments, the specific surface area of ​​the catalyst is 200-1000m 2 / g, for example, 200m 2 / g, 220m 2 / g, 240m 2 / g, 260m 2 / g, 280m 2 / g、300m 2 / g, 350m 2 / g, 400m 2 / g, 450m 2 / g、500m 2 / g、600m 2 / g、700m 2 / g、800m 2 / g、900m 2 / g、1000m 2 / g or any value in between.

[0019] In some preferred embodiments, the specific surface area of ​​the catalyst is 200-500m 2 / g.

[0020] In a third aspect, the present invention provides a method for treating wastewater containing DMSO, comprising subjecting a mixed solution of wastewater containing DMSO and hydrogen peroxide to a Fenton reaction in the presence of a Fenton catalyst obtained by the preparation method of the first aspect.

[0021] In some embodiments, in the mixed solution, the volume ratio of the wastewater to hydrogen peroxide is (10-100):1, for example, 20:1, 40:1, 60:1, 80:1, 100:1 or any value therebetween. In some preferred embodiments, in the mixed solution, the volume ratio of the wastewater to hydrogen peroxide is (20-50):1.

[0022] In some embodiments, the pH of the mixed solution is 2-5, for example, 2.5, 3, 3.5, 4, 4.5, 5 or any value therebetween.

[0023] In some embodiments, the total organic carbon TOC content in the wastewater is 70 ppm-3500 ppm, for example, 100 ppm, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, 2500 ppm, 3000 ppm, 3500 ppm or any value therebetween.

[0024] In some embodiments, the Fenton reaction is enhanced.

[0025] In some embodiments, the strengthening treatment is selected from at least one of microwave treatment, ultrasonic treatment, electric heating, infrared heating or steam heating.

[0026] In some embodiments, the temperature of the Fenton reaction is 50°C-100°C, such as 50°C, 60°C, 70°C, 80°C, 90°C, 100°C or any value therebetween. In some preferred embodiments, the temperature of the Fenton treatment is 60°C-90°C.

[0027] In some embodiments, the volume space velocity of the wastewater is 0.1 h -1 -2.0h -1 .

[0028] In some embodiments, the method further comprises post-treating the effluent after the Fenton reaction.

[0029] In some embodiments, the post-treatment comprises filtration and / or flocculation.

[0030] In some embodiments, the filter aid used in the filtration is selected from at least one of diatomaceous earth, perlite, cellulose, asbestos, graphite powder, sawdust, magnesium oxide, gypsum, activated carbon or clay.

[0031] In some embodiments, the working pressure of the filtration is 0.01 MPa-0.6 MPa.

[0032] In some embodiments, if the filtered water meets the requirement of DMSO removal rate greater than 90%, it can be directly reused; if it does not meet the requirement of DMSO removal rate greater than 90%, flocculation is performed.

[0033] In some embodiments, the flocculant used in the flocculation includes at least one of aluminum salt or iron salt, preferably polyferric sulfate.

[0034] In some embodiments, the flocculant is added in an amount of 0.1 wt% to 0.5 wt%.

[0035] In some embodiments, the method further comprises adjusting the pH of the effluent after flocculation to 7-8.

[0036] In a fourth aspect, the present invention provides the use of the Fenton catalyst obtained by the preparation method described in the first aspect, the Fenton catalyst described in the second aspect, or the treatment method described in the third aspect in industrial wastewater treatment.

[0037] In some embodiments, the industrial wastewater is wastewater containing DMSO.

[0038] The present invention has the following beneficial effects:

[0039] The heterogeneous Fenton catalyst raw material provided by the present invention adopts natural minerals, and the preparation cost is low; the wastewater treatment method solves the problem that DMSO wastewater is difficult to biodegrade, and the final effluent can be reused, turning waste into treasure, and the process is simple and efficient. In summary, the wastewater treatment method has good effect, technical applicability, economic feasibility and the like. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to constitute any limitation of the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concepts of the present disclosure. Such structures and technologies are also described in many publications.

[0041] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0042] The present invention will be described in detail below through examples.

[0043] In the present invention, the treatment effect of DMSO wastewater is represented by the total organic carbon (TOC) of the effluent, and the DMSO removal rate is defined as the value of TOC reduced after treatment divided by the value of TOC in the raw water.

[0044] In the examples and comparative examples of the present invention, the DMSO wastewater is derived from wastewater generated during the distillation of carbon fiber wastewater, and the DMSO content of the raw water is about 0.64%, and TOC=450 ppm.

[0045] In the examples and comparative examples of the present invention, the contents of Fe and Cu in the minerals were tested by an ICP emission spectrometer.

[0046] The reagents used in the following examples are commercially available and of analytical grade.

[0047] Example 1

[0048] (1) Preparation of heterogeneous Fenton catalyst: 890 g of crucible clay, 23.6 g of malachite, 500 g of β molecular sieve as adsorption component, 1000 g of attapulgite as matrix, 35 g of cellulose, 100 g of sesbania powder and 1 L of water were put into a kneader and kneaded for 30 min. The material was dug out and extruded into strips. After one week of crystal growth, it was sent into a muffle furnace and calcined at 550° C. for 4 h. The Fe content of this catalyst was about 3%, the molar ratio of iron to copper was 1.5:1, the mass ratio of adsorption component to matrix was 0.5:1, and the specific surface area of ​​this catalyst was 258 m 2 / g.

[0049] (2) 300 mL of catalyst was loaded into the heterogeneous reactor, and the heating was turned on and preheated to 80°C. DMSO wastewater (DMSO content of about 0.64%, TOC = 450 ppm) and hydrogen peroxide were respectively adjusted to pH 3 by adding sulfuric acid, and then the feed was pumped into the heterogeneous Fenton reactor. The flow rate of DMSO wastewater through the catalyst bed was 0.25 mL / min, and the flow rate of H2O2 through the catalyst bed was 0.01 mL / min, that is, the volume space velocity of water through the catalyst bed was 0.5 h -1 , the TOC of the effluent is 113ppm.

[0050] (3) The effluent from step (2) is passed into a filtration device at a working pressure of 0.4 MPa. Activated carbon is used as a filter aid. The TOC of the effluent from the filtration device is 55 ppm.

[0051] (4) The effluent from step (3) is added with polyferric sulfate at a mass concentration of 0.0025%, and then the pH is adjusted to 8 using 5% calcium oxide. The TOC of the effluent after filtration is 20 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent can be reused.

[0052] Example 2

[0053] (1) Preparation of heterogeneous Fenton catalyst: 890 g of crucible clay, 18.6 g of malachite, 500 g of β molecular sieve as adsorption component, 1000 g of attapulgite as matrix, 35 g of cellulose, 100 g of sesbania powder and 1 L of water were put into a kneader and kneaded for 30 min. The material was dug out and extruded into strips. After one week of crystal growth, it was sent into a muffle furnace and calcined at 550° C. for 4 h. The Fe content of this catalyst was about 3%, the molar ratio of iron to copper was 1.9:1, the mass ratio of adsorption component to matrix was 0.5:1, and the specific surface area of ​​this catalyst was 250 m 2 / g.

[0054] (2) 300 mL of catalyst was loaded into the heterogeneous reactor, and the heating was turned on and preheated to 80°C. DMSO wastewater (DMSO content of about 0.64%, TOC = 450 ppm) and hydrogen peroxide were respectively adjusted to pH 3 by adding sulfuric acid, and then the feed was pumped into the heterogeneous Fenton reactor. The flow rate of DMSO wastewater through the catalyst bed was 0.25 mL / min, and the flow rate of H2O2 through the catalyst bed was 0.01 mL / min, that is, the volume space velocity of water through the catalyst bed was 0.5 h -1 , the TOC of the effluent is 120ppm.

[0055] (3) The effluent from step (2) was passed into a filtration device at a working pressure of 0.4 MPa. Activated carbon was used as a filter aid. The TOC of the effluent from the filtration device was 63 ppm.

[0056] (4) The effluent from step (3) is added with polyferric sulfate at a mass concentration of 0.0025%, and then the pH is adjusted to 8 using 5% calcium oxide. The TOC of the effluent after filtration is 25 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent can be reused.

[0057] Example 3

[0058] The catalyst was prepared by the same method as in Example 1, except that the molar ratio of Fe to Cu was 5:1. The specific surface area of ​​the catalyst was 248 m 2 / g.

[0059] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 45 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0060] Example 4

[0061] The catalyst was prepared by the same method as in Example 1, except that the molar ratio of Fe to Cu was 2.5:1. The specific surface area of ​​the catalyst was 252 m 2 / g.

[0062] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 40 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0063] Example 5

[0064] The catalyst was prepared by the same method as in Example 1, except that the molar ratio of Fe to Cu was 1:2. The specific surface area of ​​the catalyst was 245 m 2 / g.

[0065] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 44 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0066] Example 6

[0067] The catalyst was prepared by the same method as in Example 1, except that the mass ratio of the adsorbed component to the matrix was 0.05:1. The specific surface area of ​​the catalyst was 220 m 2 / g.

[0068] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 45 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0069] Example 7

[0070] The catalyst was prepared by the same method as in Example 1, except that the mass ratio of the adsorbed component to the matrix was 1:1. The specific surface area of ​​the catalyst was 300 m 2 / g.

[0071] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 43 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0072] Example 8

[0073] The catalyst was prepared by the same method as in Example 1, except that the mass ratio of the adsorbent component to the matrix was 5:1. The specific surface area of ​​the catalyst was 350 m 2 / g.

[0074] The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 42 ppm, reaching the standard of DMSO removal rate greater than 90%, and the effluent could be reused.

[0075] Example 9

[0076] (1) Preparation of heterogeneous Fenton catalyst: 890g crucible clay, 23.6g malachite, 500g β molecular sieve as adsorption component, 1000g attapulgite as matrix, 35g cellulose, 100g sesbania powder and 1L water were put into a kneading machine and kneaded for 30min. The material was dug out and squeezed into strips. After one week of crystal growth, it was sent into a muffle furnace and calcined at 550℃ for 4h. The Fe content of this catalyst is about 3%, the molar ratio of iron to copper is 1.5:1, and the mass ratio of adsorption component to matrix is ​​0.5:1. The specific surface area of ​​this catalyst is 258m 2 / g.

[0077] (2) 300 mL of catalyst was loaded into the heterogeneous reactor without preheating the reactor. DMSO wastewater (DMSO content of about 0.64%, TOC = 450 ppm) and hydrogen peroxide were respectively adjusted to pH 3 by sulfuric acid, and then fed into the heterogeneous Fenton reactor by a feed pump. The flow rate of DMSO wastewater through the catalyst bed was 0.25 mL / min, and the flow rate of H2O2 through the catalyst bed was 0.01 mL / min, that is, the volume space velocity of water through the catalyst bed was 0.5 h -1 , the TOC of the effluent is 433ppm.

[0078] (3) The effluent from step (2) was passed into a filtration device at a working pressure of 0.4 MPa. Activated carbon was used as a filter aid. The TOC of the effluent from the filtration device was 252 ppm.

[0079] (4) The effluent from step (3) was added with polyferric sulfate at a mass concentration of 0.0025%, and then the pH was adjusted to 8 using 5% calcium oxide. The TOC of the effluent after filtration was 230 ppm, which did not meet the standard of DMSO removal rate greater than 90%, and the effluent was unqualified.

[0080] Comparative Example 1

[0081] (1) Preparation of heterogeneous Fenton catalyst: 890 g of crucible clay, 23.6 g of malachite, 1500 g of attapulgite matrix, 35 g of cellulose, 100 g of sesbania powder and 1 L of water were put into a kneader and kneaded for 30 min. The material was dug out and squeezed into strips. After one week of crystal growth, it was sent into a muffle furnace and calcined at 550 ° C for 4 h. The Fe content of this catalyst is about 3%, and the molar ratio of iron to copper is 1.5:1. The specific surface area of ​​this catalyst is 102 m 2 / g.

[0082] (2) 300 mL of catalyst was loaded into the heterogeneous reactor, and the heating was turned on and preheated to 80°C. DMSO wastewater (DMSO content of about 0.64%, TOC = 450 ppm) and hydrogen peroxide were respectively adjusted to pH 3 by adding sulfuric acid, and then the feed was pumped into the heterogeneous Fenton reactor. The flow rate of DMSO wastewater through the catalyst bed was 0.25 mL / min, and the flow rate of H2O2 through the catalyst bed was 0.01 mL / min, that is, the volume space velocity of water through the catalyst bed was 0.5 h -1 , the TOC of the effluent is 442ppm.

[0083] (3) The effluent from step (2) is passed into a filtration device at a working pressure of 0.4 MPa. Activated carbon is used as a filter aid. The TOC of the effluent from the filtration device is 270 ppm.

[0084] (4) The effluent from step (3) was added with polyferric sulfate at a mass concentration of 0.0025%, and then the pH was adjusted to 8 using 5% calcium oxide. The TOC of the effluent after filtration was 265 ppm, which did not meet the standard of DMSO removal rate greater than 90%, and the effluent was unqualified.

[0085] Comparative Example 2

[0086] (1) Preparation of heterogeneous Fenton catalyst: 89.25 g of ferrous sulfate heptahydrate was added to 200 mL of water to prepare solution A, 51.5 g of copper nitrate trihydrate was added to 200 mL of water to prepare solution B, 1 L of 2 mol / L sodium hydroxide was used as the base liquid, solution A and solution B were added dropwise at the same time, stirred for 60 min, aged for 24 h, dried at 120 ° C for 8 h, and finally calcined at 550 ° C for 4 h to obtain a catalyst with a specific surface area of ​​50 m 2 / g.

[0087] (2) The DMSO wastewater was treated in the same manner as in Example 1. The TOC of the effluent after treatment and filtration was 300 ppm, which did not meet the standard of DMSO removal rate greater than 90%. The effluent could not be reused.

[0088] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing a Fenton catalyst, comprising kneading a mixture containing an iron-containing mineral and a copper-containing mineral and an optional adsorption component and / or a matrix into a mold, and then calcining it.

2. The preparation method according to claim 1, characterized in that: The iron-containing mineral comprises at least one of hematite, limonite, crucible clay or iron mud; and / or The copper-containing mineral includes at least one of cuprite, malachite, azurite, and chrysocolla; Preferably, the molar ratio of the Fe element in the iron-containing mineral to the Cu element in the copper-containing mineral is (0.5-5):1, preferably (1-2):1; Preferably, the content of the Fe element is 0.5wt%-5wt% based on the total amount of the iron-containing mineral and the copper-containing mineral.

3. The preparation method according to claim 1 or 2, characterized in that: The adsorption component is selected from molecular sieves, preferably selected from at least one of phosphate aluminum molecular sieves or silicon aluminum molecular sieves, more preferably selected from at least one of β molecular sieves, Y-type molecular sieves, mordenite, MCM-22, MCM-41, SAPO-34 or SAPO-5; The matrix is ​​selected from at least one of attapulgite, diatomaceous earth, bentonite or kaolin; Preferably, the mass ratio of the adsorption component to the matrix is ​​(0.05-5):1, preferably (0.1-0.8):1; Preferably, the mixture also includes a molding agent, More preferably, the molding agent comprises cellulose and / or sesbania powder, More preferably, the mass ratio of the molding agent to the matrix is ​​(0.02-0.5):1, preferably (0.05-0.2):

1.

4. The preparation method according to any one of claims 1 to 3, characterized in that The calcination temperature is 500° C.-700° C., and the calcination time is 3 h-20 h.

5. A Fenton catalyst obtained by the preparation method according to any one of claims 1 to 4, comprising an iron-containing oxide and a copper-containing oxide; Preferably, the specific surface area of ​​the catalyst is 200-1000m 2 / g, preferably 200-500m 2 / g.

6. A method for treating wastewater containing dimethyl sulfoxide (DMSO), comprising subjecting a mixed solution of wastewater containing DMSO and hydrogen peroxide to a Fenton reaction in the presence of a Fenton catalyst obtained by the preparation method according to any one of claims 1 to 4.

7. The processing method according to claim 6, characterized in that: In the mixed solution, the volume ratio of the wastewater to hydrogen peroxide is (10-100):1, preferably (20-50):1; Preferably, the pH of the mixed solution is 2-5; Preferably, the content of total organic carbon (TOC) in the wastewater is 70ppm-3500ppm.

8. The processing method according to claim 6 or 7, characterized in that: The Fenton reaction is enhanced. Preferably, the strengthening treatment is selected from at least one of microwave treatment, ultrasonic treatment, electric heating, infrared heating or steam heating; Preferably, the temperature of the Fenton reaction is 50°C-100°C, preferably 60°C-90°C; Preferably, the volume space velocity of the wastewater is 0.1h -1 -2.0h -1 .

9. The processing method according to any one of claims 6 to 8, characterized in that: The method further comprises post-processing the effluent after the Fenton reaction. Preferably, the post-treatment comprises filtration and / or flocculation; More preferably, the filter aid used in the filtration is selected from at least one of diatomaceous earth, perlite, cellulose, asbestos, graphite powder, sawdust, magnesium oxide, gypsum, activated carbon or clay; More preferably, the working pressure of the filtration is 0.01MPa-0.6MPa; More preferably, the flocculant used in the flocculation comprises at least one of an aluminum salt or an iron salt, preferably polyferric sulfate; More preferably, the amount of the flocculant added is 0.1wt%-0.5wt%; More preferably, the method further comprises adjusting the pH of the effluent after flocculation to 7-8.

10. Use of the Fenton catalyst obtained by the preparation method according to any one of claims 1 to 4, the Fenton catalyst according to claim 5, or the treatment method according to any one of claims 6 to 9 in the treatment of industrial wastewater, especially wastewater containing DMSO.