Wet oxidation catalyst, method for preparing and using the same, and method for treating organic waste water

Abstract

The present application provides a wet oxidation catalyst, a preparation method and application thereof. The catalyst comprises a carrier, a wet oxidation active metal oxide, the relative amount (x10 ‑2 ) of L acid of the catalyst is 0.01-1.50; and / or the relative amount (x10 ‑2 ) of B acid is 0.01-0.13. The present application provides a treatment method of organic wastewater. The organic wastewater is contacted with an oxidant in the presence of the catalyst to remove COD in the wastewater. According to a preferred embodiment, the catalyst comprises 48 parts of MoO3, 4 parts of Bi2O3, 16 parts of NiO, 12 parts of MnO2 and 20 parts of SiO2 carrier components by weight. After mixing the industrial wastewater with oxygen and passing through a wet oxidation reactor loaded with the catalyst, under the conditions of a reaction temperature of 260 DEG C, a pressure of 7.0 MPa and a volume ratio of oxygen to industrial wastewater of 200, the COD removal rate is 99.6%, and excellent results are achieved.

Description

Technical Field

[0001] This invention relates to the field of wet oxidation, specifically to a wet oxidation catalyst, its preparation method and application, and a method for treating organic wastewater. Background Technology

[0002] Compared to many other wastewater treatment technologies, catalytic wet oxidation (CWAO) technology has a high efficiency in oxidizing and degrading high-concentration organic pollutants, and can completely solve the environmental problems of high-concentration wastewater from industries such as petrochemicals, pesticides, dyes, and food processing.

[0003] Therefore, heterogeneous catalysts have become a research hotspot in recent years. Heterogeneous catalysts are mainly divided into two categories: noble metals and composite metal oxides. Among them, composite metal oxide catalysts mostly use Al2O3, SiO2 or their composite oxides as supports, and the active components are mainly oxides of metal elements such as Mo, Bi, Fe, Cu, Co, Ni, and Mn.

[0004] CN101219376B discloses a catalyst for wastewater treatment, which uses γ-Al2O3 as a support, Mn metal oxide, Sn metal oxide as the main active component, and Sb oxide as a promoter. CN101485987B belongs to the field of water treatment technology and environmental functional materials. This catalyst is prepared by a layered impregnation method using powdered zinc-aluminum hydrotalcite as a support, Fe as the active component, and Ce and Ti as promoters. Summary of the Invention

[0005] This invention addresses the problem of low chemical oxygen demand (COD) removal rate in the treatment of organic wastewater in existing technologies by providing a novel wet oxidation catalyst for treating organic wastewater. When using the catalyst to treat organic wastewater, it has the advantage of high COD degradation efficiency.

[0006] According to a first aspect of the present invention, the present invention provides a wet oxidation catalyst comprising: a support, a wet oxidation active metal oxide, wherein the relative amount of L acid in the catalyst is (×10) -2 The relative amounts of 0.01 to 1.30 and / or β-acid (×10) are 0.01 to 1.30. -2 The value ranges from 0.01 to 0.12.

[0007] According to a second aspect of the present invention, the present invention provides a method for preparing the wet oxidation catalyst of the present invention, the method comprising:

[0008] S1, in the presence of organic acid, the carrier source is mixed with a solution containing a wet oxidizing active metal source to obtain a slurry;

[0009] S2, spray-dry the slurry to obtain powder;

[0010] S3, the powder, water and binder are bonded together in a bonding machine, and then formed, dried and calcined to obtain the wet oxidation catalyst.

[0011] According to a third aspect of the present invention, the present invention provides the application of the catalyst described herein in the treatment of industrial organic wastewater, preferably said industrial organic wastewater is herbicide wastewater and / or food additive wastewater.

[0012] According to a fourth aspect of the present invention, the present invention provides a method for treating organic wastewater, wherein the organic wastewater is reacted with an oxidant in the presence of the catalyst described in the present invention to remove COD from the wastewater.

[0013] The relative amount of L-acid in the catalyst of the present invention (×10) -2 The relative amount of β-acid is 0.01–1.30; -2 The concentration of oxygen in the catalyst is 0.01–0.12. Using the catalyst of this invention, industrial wastewater is mixed with oxygen and then passed through a wet oxidation reactor containing the catalyst. According to a preferred embodiment, the catalyst comprises 48 parts by weight of MoO3, 4 parts by weight of Bi2O3, 16 parts by weight of NiO, 12 parts by weight of MnO2, and 20 parts by weight of SiO2 support components. Under the conditions of a reaction temperature of 260°C, a pressure of 7.0 MPa, and a volume ratio of oxygen to industrial wastewater of 200, the COD removal rate after the reaction is 99.6%, achieving excellent results.

[0014] The method for preparing the catalyst of the present invention involves adding an organic carboxylic acid in combination with other technical means during the catalyst slurry preparation process, thereby obtaining the acid-based catalyst of the present invention.

[0015] The catalyst of this invention has the advantage of high COD degradation efficiency when treating organic wastewater. Attached Figure Description

[0016] Figure 1 The image shows the infrared pyridine spectrum of the catalyst in Example 2 and Comparative Example 2. Detailed Implementation

[0017] The endpoints and any values ​​of the ranges disclosed herein 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0018] This invention provides a wet oxidation catalyst, which comprises: a support, a wet oxidation active metal oxide, and the relative amount of L acid in the catalyst (×10) -2The relative amounts of 0.01 to 1.50 and / or β-acid (×10) are 0.01 to 1.50. -2 The value ranges from 0.01 to 0.13.

[0019] The catalyst of this invention has the advantage of high COD degradation efficiency when treating organic wastewater.

[0020] According to a preferred embodiment of the present invention, the relative amount of L acid in the catalyst (×10) -2 ): 0.8~1.5; Relative amount of Brønsted acid (×10) -2 (%): 0.07~0.13. The catalyst of this invention has the advantage of high COD degradation efficiency when treating organic wastewater.

[0021] In this invention, the composition and content of the catalyst can be selected from a wide range, and commonly used ratios can be applied to this invention. According to a preferred embodiment of this invention, the catalyst contains 20 to 40 parts of support and 60 to 80 parts of wet oxidation active metal oxide per 100 parts by weight.

[0022] In this invention, the range of types of carriers that can be selected is relatively wide, and commonly used types can be applied to this invention. For example, they can include, but are not limited to, SiO2 and / or Al2O3.

[0023] In this invention, the wet oxidation active metal oxide can be a conventional wet oxidation active metal oxide. For example, the wet oxidation active metal oxide of this invention includes, but is not limited to, oxides of at least two metal elements selected from Mo, Bi, Fe, Co, Ni and Mn.

[0024] According to a preferred embodiment of the present invention, the wet oxidation active metal oxide preferably includes oxides of four metal elements: Mo, Bi, Ni and Mn. More preferably, the weight ratio of Mo oxide, Bi oxide, Ni oxide and Mn oxide is 48:2-10:12-18:8-14, and more preferably 48:4-8:14-16:10-12.

[0025] Catalysts possessing the aforementioned properties of this invention can achieve the objectives of this invention, and there are no special requirements for their preparation methods. According to a preferred embodiment of this invention, this invention provides a method for preparing the wet oxidation catalyst described herein, the method comprising:

[0026] S1, in the presence of organic acid, the carrier source is mixed with a solution containing a wet oxidizing active metal source to obtain a slurry;

[0027] S2, spray-dry the slurry to obtain powder;

[0028] S3, the powder, water and binder are bonded together in a bonding machine, and then formed, dried and calcined to obtain the wet oxidation catalyst.

[0029] According to a preferred embodiment of the present invention, in preferred step S1, the pulping conditions include a temperature of 70°C to 85°C.

[0030] In this invention, the pulping time is determined based on the temperature. According to a preferred embodiment of the invention, the pulping time is preferably 1.5 to 2.5 hours.

[0031] In this invention, the range of organic acids that can be selected in step S1 is relatively wide, preferably selected from one or more of formic acid, propionic acid, benzoic acid, and stearic acid. According to a preferred embodiment of the invention, the organic acid is preferably a mixture of propionic acid and benzoic acid in a weight ratio of 0.1-10:1. In the embodiments of the invention, a weight ratio of propionic acid to benzoic acid of 1:1 is used as an example to illustrate the advantages of the invention, but this should not be construed as limiting the scope of the invention.

[0032] In this invention, the amount of organic acid used is preferably less than 5% by weight of the finished catalyst product, preferably less than 3% by weight, and more preferably 1-2% by weight.

[0033] In this invention, the solid content of the slurry can be selected from a wide range. For this invention, the solid content of the slurry is 25-40% by weight.

[0034] In this invention, there are no special requirements for the spray drying conditions. For this invention, in step S2, the spray drying temperature is preferably 350-500℃, preferably 380-450℃, and more preferably 420-440℃. The spray drying time is determined according to specific needs. For this invention, the spray drying time is preferably 20-80 min, preferably 30-60 min, and more preferably 30-50 min.

[0035] In this invention, in step S3, the amount of binder added, calculated as oxide, can be selected from a wide range, preferably less than 5% of the total mass of the catalyst product, and more preferably 2 to 4%.

[0036] In this invention, the type of adhesive selected in step S3 is relatively wide. For this invention, it preferably includes at least one of PEG, CMC, and methylcellulose. In the embodiments of this invention, methylcellulose is used as an example, but this should not be construed as limiting the scope of the invention.

[0037] According to a preferred embodiment of the present invention, in step S3, the amounts of powder, water and binder can be used in accordance with conventional methods. Based on experience, the powder is added in accordance with a theoretical amount of 100 parts and the water is added in accordance with an empirical amount of 90 parts, but this should not limit the scope of the present invention.

[0038] According to a preferred embodiment of the present invention, in step S3, the drying and calcination conditions are not particularly required and can be conventional conditions.

[0039] According to a preferred embodiment of the present invention, the drying temperature is 95°C to 115°C. The drying time is determined according to the drying temperature; for the present invention, the preferred drying time is 12 to 16 hours. According to the present invention, it is preferable to pre-dry at room temperature for 0.5 to 3 hours before performing the aforementioned heating drying.

[0040] According to a preferred embodiment of the present invention, the roasting temperature is 400-600℃, preferably 480-530℃, and more preferably 450-550℃. The roasting time is determined according to the temperature. For the present invention, the roasting time is preferably 2.0-4.5h, more preferably 2.5-4.0h, and more preferably 2.5-3.2h.

[0041] In this invention, there are no special requirements for the bonding and molding methods, and conventional bonding and molding methods can be used. These methods will not be described in detail here.

[0042] The catalyst of this invention is particularly suitable for industrial wastewater treatment, especially industrial organic wastewater.

[0043] This invention provides the application of the catalyst described herein in the treatment of industrial organic wastewater, preferably herbicide wastewater and / or food additive wastewater.

[0044] According to a preferred embodiment of the present invention, the COD content of the industrial organic wastewater is 20,000 to 40,000 ppm.

[0045] The present invention provides a method for treating organic wastewater, the method comprising: reacting organic wastewater with an oxidant in the presence of the catalyst described in the present invention to remove COD from the wastewater.

[0046] According to a preferred embodiment of the present invention, the COD content in the organic wastewater is 20,000 to 40,000 ppm.

[0047] The present invention does not explicitly limit the source of organic wastewater, such as the herbicide wastewater and food additive wastewater.

[0048] According to a preferred embodiment of the present invention, the oxidant is oxygen or air.

[0049] According to a preferred embodiment of the present invention, the reaction temperature is 200–280°C and the reaction pressure is 4.0–9.0 MPa.

[0050] This invention utilizes infrared spectroscopy based on pyridine adsorption to determine acidity characterization (acidity and acid strength). A BIO-RADF TS 3000 infrared spectrometer (USA) was employed. The specific spectral acquisition method was as follows: approximately 10 mg of sample was weighed, pressed into a Φ15 mm circular sheet, placed in a quartz sample cell frame, and subjected to a vacuum of 4 × 10⁻⁶. -3 After dehydration at 400℃ for 2 hours under Torr (1 mmHg) conditions, the temperature was lowered to 200℃, followed by pyridine adsorption for 10 min, equilibration for 5 min, desorption under low vacuum for 10 min, and high vacuum for 30 min, with IR scanning performed. The temperature was then increased to 300℃ for another 10 min, equilibrated for 5 min, and IR scanning was performed again; finally, the temperature was increased to 400℃ for another 10 min, equilibrated for 5 min, and IR scanning was performed again. The spectrum was obtained at 1450 cm⁻¹. -1 This is considered a characteristic absorption peak for L-acids; 1540 cm⁻¹ -1 It is considered a characteristic absorption peak of Brønsted acid, while 1610 cm⁻¹ -1 This is considered a characteristic absorption peak shared by both L-acid and Brønsted acid. The calculation formula is: C(L-acid) = 1.42 * I(L) * R * R / W; C(Brønsted acid) = 1.88 * I(B) * R * R / W, where I(L) is the peak area of ​​L-acid, I(B) is the peak area of ​​Brønsted acid, R is the tablet diameter, and W is the tablet weight.

[0051] The evaluation method for the catalyst of this invention is as follows: 100g of catalyst was taken and loaded into a wet oxidation reactor (the reactor is a fixed-bed reactor with an inner diameter of 22mm and a reactor length of 700mm). Herbicide wastewater (COD: 35000ppm) and food additive wastewater (COD: 28000ppm) were used as raw materials, mixed with oxygen, and then passed through the wet oxidation reactor containing the catalyst. The reaction temperature was 260℃, the pressure was 7.0MPa, the volume ratio of oxygen to industrial wastewater was 180, and the mass hourly space velocity of the industrial wastewater was 1.0h⁻¹. -1 The COD of the reaction products was determined using a Hach analyzer.

[0052] To make the present invention easier to understand, the present invention will be further described in detail below with reference to embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of application of the present invention. Unless otherwise specified, the raw materials or components used in the present invention can be obtained commercially or by conventional methods.

[0053] In this invention, the method for calculating the COD removal rate is a conventional method, and there are no special requirements for this invention.

[0054] Example 1

[0055] 1. Catalyst Preparation

[0056] A solution of ammonium molybdate containing 48 parts by weight of MoO3, a solution of bismuth nitrate containing 4 parts by weight of Bi2O3, a solution of nickel nitrate containing 16 parts by weight of NiO, a solution of manganese nitrate containing 12 parts by weight of MnO2, and a silica sol containing 20 parts by weight of silica were mixed to form a slurry. The slurry temperature was 80°C and the slurry time was 2.0 h. During the slurry process, 2 parts by weight of propionic acid were added, and the solid content of the slurry was 28% by weight.

[0057] The slurry was then spray-dried (drying temperature 420℃, spray drying time 40min) to obtain powder.

[0058] 100 parts by weight of powder were mixed in a kneader, and 3 parts by weight of methylcellulose and 90 parts by weight of water were added. The mixture was stirred and kneaded for 30 minutes. The agglomerated material was dried at room temperature for 20 minutes, then extruded and sphericalized. The spherical material was first dried at room temperature for 60 minutes, and then dried in an oven at 105°C for 14 hours. Subsequently, it was calcined in a muffle furnace at 500°C for 3 hours to obtain shaped spherical catalysts with a diameter of 3 mm.

[0059] 2. Catalyst Evaluation

[0060] 100g of catalyst was loaded into a wet oxidation fixed-bed reactor for reaction. The reaction temperature was 260℃, the pressure was 7.0MPa, the volume ratio of oxygen to industrial wastewater was 180, and the mass hourly space velocity (MHV) of the industrial wastewater was 1.0 h⁻¹. -1 The COD value of the reaction products was determined using a Hach analyzer. Industrial wastewater included herbicide wastewater (COD: 35,000 ppm) and food additive wastewater (COD: 28,000 ppm).

[0061] The composition of the active components of the catalyst is shown in Table 1, the catalyst preparation conditions are shown in Table 2, and the catalyst evaluation results are shown in Table 3.

[0062] Example 2

[0063] 1. Catalyst Preparation

[0064] A slurry containing 48 parts by weight of an ammonium molybdate solution of MoO3, 4 parts by weight of a bismuth nitrate solution of Bi2O3, 16 parts by weight of a nickel nitrate solution of NiO, 12 parts by weight of a manganese nitrate solution of MnO2, 12 parts by weight of a silica sol containing silica, and 8 parts by weight of an alumina sol was prepared. The slurry preparation temperature was 80℃, and the preparation time was 2.0 h. During the slurry preparation process, 2 parts by weight of propionic acid were added, and the solid content of the slurry was 28% by weight. The slurry was then spray-dried (drying temperature was 420℃, and spray drying time was 40 min) to obtain a powder.

[0065] 100 parts by weight of powder were mixed in a kneader, and 3 parts by weight of methylcellulose and 90 parts by weight of water were added. The mixture was stirred and kneaded for 30 minutes. The agglomerated material was dried at room temperature for 20 minutes, then extruded and sphericalized. The spherical material was first dried at room temperature for 60 minutes, and then dried in an oven at 105°C for 14 hours. Subsequently, it was calcined in a muffle furnace at 500°C for 3 hours to obtain shaped spherical catalysts with a diameter of 3 mm. Figure 1 Including the infrared pyridine spectrum of the catalyst prepared in Example 2. (From...) Figure 1 It can be seen that at a wavenumber of 1450cm -1 (Characterial peak of L-acid), wavenumber 1540 cm⁻¹ -1 (Characterial peak of Brønsted acid), wavenumber 1610 cm⁻¹ -1 (Common characteristic peaks of L+B acids) all have obvious peaks.

[0066] 2. Catalyst Evaluation

[0067] 100g of catalyst was loaded into a wet oxidation fixed-bed reactor for reaction. The reaction temperature was 260℃, the pressure was 7.0MPa, the volume ratio of oxygen to industrial wastewater was 180, and the mass hourly space velocity (MHV) of the industrial wastewater was 1.0 h⁻¹. -1 The COD value of the reaction products was determined using a Hach analyzer. Industrial wastewater included herbicide wastewater (COD: 35,000 ppm) and food additive wastewater (COD: 28,000 ppm).

[0068] The composition of the active components of the catalyst is shown in Table 1, the catalyst preparation conditions are shown in Table 2, and the catalyst evaluation results are shown in Table 3.

[0069] Comparative Example 1

[0070] 1. Catalyst Preparation

[0071] A solution containing 48 parts by weight of ammonium molybdate (MoO3), 4 parts by weight of bismuth nitrate (Bi2O3), 16 parts by weight of nickel nitrate (NiO), 12 parts by weight of manganese nitrate (MnO2), and 20 parts by weight of silica sol were mixed to form a slurry. The slurry had a solid content of 28% by weight, the slurry temperature was 80℃, and the slurry time was 2.0 h.

[0072] The powder was obtained by spray drying (drying temperature 420℃, spray drying time 40min).

[0073] 100 parts by weight of powder were mixed in a kneader, and 3 parts by weight of methylcellulose and 90 parts by weight of water were added. The mixture was stirred and kneaded for 30 minutes. The agglomerated material was dried at room temperature for 20 minutes, then extruded and sphericalized. The spherical material was first dried at room temperature for 60 minutes, and then dried in an oven at 105°C for 14 hours. Subsequently, it was calcined in a muffle furnace at 500°C for 3 hours to obtain shaped spherical catalysts with a diameter of 3 mm.

[0074] 2. Catalyst Evaluation

[0075] 100g of catalyst was loaded into a wet oxidation fixed-bed reactor for reaction. The reaction temperature was 260℃, the pressure was 7.0MPa, the volume ratio of oxygen to industrial wastewater was 180, and the mass hourly space velocity (MHV) of the industrial wastewater was 1.0 h⁻¹. -1 The COD value of the reaction products was determined using a Hach analyzer. Industrial wastewater included herbicide wastewater (COD: 35,000 ppm) and food additive wastewater (COD: 28,000 ppm).

[0076] The composition of the active components of the catalyst is shown in Table 1, the catalyst preparation conditions are shown in Table 2, and the catalyst evaluation results are shown in Table 3.

[0077] Comparative Example 2

[0078] 1. Catalyst Preparation

[0079] A slurry containing 48 parts by weight of an ammonium molybdate solution of MoO3, 4 parts by weight of a bismuth nitrate solution of Bi2O3, 16 parts by weight of a nickel nitrate solution of NiO, 12 parts by weight of a manganese nitrate solution of MnO2, 12 parts by weight of a silica sol containing 12 parts by weight of silica, and 8 parts by weight of an alumina sol was prepared. The slurry preparation temperature was 80℃, the preparation time was 2.0 h, and the solid content of the slurry was 28% by weight. The slurry was then spray-dried (drying temperature was 420℃, spray drying time was 40 min) to obtain a powder.

[0080] 100 parts by weight of powder were mixed in a kneader, then 3 parts by weight of methylcellulose and 90 parts by weight of water were added, and the mixture was stirred and kneaded for 30 minutes. The resulting agglomerated material was dried at room temperature for 20 minutes, then extruded and sphericalized. The spherical material was first dried at room temperature for 60 minutes, then dried in an oven at 105°C for 14 hours. Subsequently, it was calcined in a muffle furnace at 500°C for 3.0 hours to obtain shaped spherical catalysts with a diameter of 3 mm. Figure 1 It can be seen that at a wavenumber of 1450cm -1 (Characterial peak of L-acid), wavenumber 1540 cm⁻¹ -1 (Characterial peak of Brønsted acid), wavenumber 1610 cm⁻¹ -1 The peak area of ​​(common characteristic peak of L+B acid) is significantly smaller than that of Example 2.

[0081] 2. Catalyst Evaluation

[0082] 100g of catalyst was loaded into a wet oxidation fixed-bed reactor for reaction. The reaction temperature was 260℃, the pressure was 7.0MPa, the volume ratio of oxygen to industrial wastewater was 180, and the mass hourly space velocity (MHV) of the industrial wastewater was 1.0 h⁻¹. -1The COD value of the reaction products was determined using a Hach analyzer. Industrial wastewater included herbicide wastewater (COD: 35,000 ppm) and food additive wastewater (COD: 28,000 ppm).

[0083] The composition of the active components of the catalyst is shown in Table 1, the catalyst preparation conditions are shown in Table 2, and the catalyst evaluation results are shown in Table 3.

[0084] The active components of the catalysts in the other examples and comparative examples are shown in Table 1, the catalyst preparation conditions are shown in Table 2, and the catalyst evaluation results are shown in Table 3.

[0085] Table 1

[0086]

[0087]

[0088] *The amount of organic carboxylic acid added refers to the weight ratio of the amount of the product catalyst.

[0089] Table 2

[0090]

[0091] Table 3

[0092]

[0093] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0094] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A wet oxidation catalyst, characterized by, The catalyst contains a carrier, a wet oxidation active metal oxide, the relative amount of L acid of the catalyst is (0.8-1.5) x 10 -2 ; the relative amount of B acid is (0.07-0.13) x 10 -2 , the carrier comprises SiO2 and / or Al2O3, the wet oxidation active metal oxide comprises oxides of four metal elements of Mo, Bi, Ni and Mn, the weight ratio of Mo oxide, Bi oxide, Ni oxide and Mn oxide is 48:2-10:12-18:8-14.

2. The catalyst according to claim 1, wherein, the catalyst contains 20-40 parts of the carrier and 60-80 parts of the wet oxidation active metal oxide, based on 100 parts by weight.

3. The catalyst according to claim 1, wherein, the weight parts ratio of Mo oxide, Bi oxide, Ni oxide and Mn oxide is 48:4-8:14-16:10-12.

4. A method for preparing the wet oxidation catalyst according to any one of claims 1-3, the method comprising: S1, mixing a carrier source with a solution containing a wet oxidation active metal source in the presence of an organic acid to obtain a slurry, the organic acid being selected from one or more of formic acid, propionic acid, benzoic acid and stearic acid; S2, spray drying the slurry to obtain a powder; S3, binding the powder, water and a binder in a binder, shaping, drying and calcining to obtain the wet oxidation catalyst.

5. The method according to claim 4, wherein, in step S1, the slurry preparation conditions include a temperature of 70-85°C and / or a slurry preparation time of 1.5-2.5h; and / or in step S1, the organic acid is a mixture of propionic acid and benzoic acid, the weight ratio of the two being 0.1-10:1; and / or the amount of the organic acid is 5% by weight or less of the target catalyst product; and / or the solid content of the slurry is 25-40% by weight.

6. The method according to claim 5, wherein, the amount of the organic acid is 3% by weight or less of the target catalyst product.

7. The method according to claim 6, wherein, the amount of the organic acid is 1-2% by weight of the target catalyst product.

8. The method of any of claims 4-7, wherein, in step S2, the spray drying temperature is 350-500°C and the spray drying time is 20-80min.

9. The method of claim 8, wherein, in step S2, the spray drying temperature is 420-440°C and the spray drying time is 30-50min.

10. The method according to any one of claims 4-7, wherein, in step S3, the amount of the binder added is 5% or less of the total mass of the catalyst product; and / or in step S3, the binder comprises at least one of PEG, CMC and methyl cellulose.

11. The method according to claim 10, wherein, in step S3, the amount of the binder added is 2-4% of the total mass of the catalyst product; and / or in step S3, the binder is methyl cellulose.

12. The method of any one of claims 4-7, wherein, in step S3, the drying temperature is 95-115°C and the drying time is 12-16h; and / or the calcining temperature is 400-600°C and the calcining time is 2.0-4.5h.

13. The method of claim 12, wherein, in step S3, the calcining temperature is 480-530°C and the calcining time is 2.5-3.2h.

14. Use of the catalyst according to any one of claims 1-3 in treating industrial organic wastewater.

15. Use according to claim 14, wherein, the industrial organic wastewater is herbicide wastewater and / or food additive wastewater.

16. The use according to claim 14, wherein, the content of COD of the industrial organic wastewater is 20000-40000ppm.

17. A method for treating organic wastewater, characterized by, The organic waste water is contacted with an oxidant in the presence of the catalyst of any one of claims 1-3 to remove COD in the waste water.

18. The treatment method of claim 17, wherein, The organic waste water is selected from herbicide waste water and / or food additive waste water.

19. The treatment method of claim 17, wherein, The oxidant is oxygen or air.

20. The treatment method of claim 17, wherein, The reaction temperature is 200-280 DEG C and the reaction pressure is 4.0-9.0 MPa.

21. The treatment method of claim 17, wherein, The content of COD in the organic waste water is 20,000-40,000 ppm.

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