A Fenton catalyst and its preparation method and application

Abstract

The invention discloses a Fenton catalyst and a preparation method and application thereof, belonging to the technical field of wastewater treatment. The preparation method of the Fenton catalyst of the invention comprises the following steps: subjecting a solution containing ferric chloride hexahydrate, terephthalic acid and riboflavin (VB2) to a hydrothermal reaction to obtain a Fenton catalyst VB2@MIL‑101(Fe); the temperature of the hydrothermal reaction is 110 to 150° C., and the time is 20 to 24 hours; the molar ratio of ferric chloride hexahydrate, terephthalic acid and riboflavin is 2:1:(0.1 to 0.6); the prepared Fenton catalyst can be used to improve Fe 3+ / Fe 2+ Cycle efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and more specifically to a Fenton catalyst and a preparation method and application thereof. Background Art

[0002] The abuse of antibiotics in livestock and poultry and aquaculture and the effective treatment of antibiotic wastewater are receiving increasing attention. In particular, various antibiotics such as enrofloxacin, florfenicol and sulfamethoxazole are often used in aquaculture to prevent and treat fish diseases and increase production. These drugs play an important role in preventing and treating bacterial diseases, red fin disease and enteritis. However, the long-term use and improper treatment of antibiotics can lead to serious environmental pollution and ecological risks. Antibiotics in the environment can enter the water body through surface runoff, exist in the river sediment for a long time, inhibit the growth of certain organisms, and induce the production of drug-resistant bacteria and resistance genes.

[0003] At present, the commonly used methods for removing antibiotics are advanced oxidation treatment, biological treatment and ecological treatment. Advanced oxidation is often used to remove antibiotics from water bodies. By regulating various catalytic conditions, a relatively efficient removal effect can be achieved. The Fenton oxidation method uses hydrogen peroxide (H2O2) mixed with divalent iron ions to produce highly oxidizing hydroxyl radicals to degrade pollutants in wastewater. It has the advantages of high efficiency and simple operation. Fe plays the role of a catalyst in Fenton oxidation. 3+ / Fe 2+ The cyclic catalysis of hydrogen peroxide generates hydroxyl radicals. In the traditional homogeneous Fenton process of organic wastewater degradation, the best effect can be achieved in the pH range of 2 to 4. The applicable pH range is narrow. At the same time, Fe 3+ Sedimentation will occur, resulting in the production of large amounts of iron sludge.

[0004] Iron-based solid catalysts to replace Fe in homogeneous Fenton reaction 2+The homogeneous Fenton technology has the advantages of fast reaction speed, wide pH range, and low iron sludge, and has attracted widespread attention. Iron-based metal organic framework materials (MOFs), as an advanced catalytic material, are composed of organic ligands and iron ions, forming a pore structure with high specific surface area and multiple active sites. It not only has a highly controllable structure, but also exhibits excellent catalytic performance. It is an ideal catalyst in the heterogeneous Fenton oxidation process. However, a Chinese patent with publication number CN118543364A discloses a preparation method and application of NH2-MIL-101 (Fe)-derived Fe-Cu bimetallic catalyst. The technical solution adopts a supramolecular self-assembly-hydrothermal process, using 2-aminoterephthalic acid, ferric chloride hexahydrate, copper nitrate trihydrate, DMF, etc. as raw materials. In the process of synthesizing the Fe-Cu bimetallic carbon material precursor, the amino modification of MIL-101 is simultaneously realized, and the Fe and Cu active sites are exposed through a low-temperature carbonization process to increase the reaction active sites, but the Fe cannot be increased. 3+ / Fe 2+ cycle efficiency. Summary of the invention

[0005] 1. Technical problem to be solved by the invention

[0006] In view of the Fe 3+ / Fe 2+ To solve the problem of low cycle efficiency, a Fenton catalyst is provided, as well as a preparation method and application thereof.

[0007] 2. Technical solution

[0008] In order to achieve the above object, the technical solution provided by the present invention is:

[0009] A method for preparing a Fenton catalyst of the present invention comprises the following steps:

[0010] A solution containing ferric chloride hexahydrate, terephthalic acid, and riboflavin (VB2) was subjected to a hydrothermal reaction to obtain a Fenton catalyst VB2@MIL-101(Fe);

[0011] The temperature of the hydrothermal reaction is 110-150°C and the time is 20-24h;

[0012] The molar ratio of the ferric chloride hexahydrate, terephthalic acid and riboflavin is 2:1:(0.1-0.6).

[0013] Preferably, the molar ratio of the ferric chloride hexahydrate, terephthalic acid and riboflavin is 2:1:(0.2-0.3).

[0014] Furthermore, the solvent of the solution includes N,N-dimethylformamide (DMF).

[0015] Preferably, the solvent of the solution is N,N-dimethylformamide.

[0016] Furthermore, in the solution, the ratio of ferric chloride hexahydrate to the solvent is 5 mmol: (30-50) mL.

[0017] Furthermore, the hydrothermal reaction further includes centrifugation, washing, drying and grinding.

[0018] Furthermore, the washing may be performed by using DMF and ethanol.

[0019] For example, wash three times with DMF and three times with ethanol.

[0020] Furthermore, the drying temperature is 50-90° C. and the drying time is 6-12 hours.

[0021] Furthermore, the grinding can be performed using an agate mortar.

[0022] Furthermore, the solution containing ferric chloride hexahydrate, terephthalic acid and riboflavin can be obtained by the following method:

[0023] S1. Dissolve ferric chloride hexahydrate and terephthalic acid in DMF to obtain a ferric chloride solution and a terephthalic acid solution;

[0024] S2. The ferric chloride solution and the terephthalic acid solution were stirred and mixed for 30 to 120 min to obtain a mixed solution C;

[0025] S3. Dissolve riboflavin in the mixed solution C, and stir and mix for 30 to 120 minutes to obtain the solution containing ferric chloride hexahydrate, terephthalic acid, and riboflavin.

[0026] The solution containing ferric chloride hexahydrate, terephthalic acid and riboflavin is prepared in the manner described, and the reactants are mixed more evenly, which is more conducive to the hydrothermal reaction and improves the uniformity of the hydrothermal reaction.

[0027] Furthermore, the present invention also provides a Fenton catalyst prepared by the above preparation method.

[0028] Furthermore, the Fenton catalyst includes MIL-101(Fe), and riboflavin is loaded on the MIL-101(Fe).

[0029] Furthermore, the crystal structure of the Fenton catalyst is a regular octahedral structure.

[0030] Furthermore, the particle size of the Fenton catalyst is 500-600 nm.

[0031] The present invention also provides a Fenton catalyst prepared by the preparation method or a method for using the Fenton catalyst to degrade florfenicol in water.

[0032] Furthermore, the Fenton catalyst is added to water containing florfenicol, and then hydrogen peroxide is added to perform an oscillation reaction.

[0033] Furthermore, the concentration of florfenicol in the water containing florfenicol is 1 to 50 mg / L.

[0034] Furthermore, the dosage of the Fenton catalyst is 0.2-0.5 g / L.

[0035] Furthermore, the dosage of the hydrogen peroxide is 10 to 30 mmol / L.

[0036] Furthermore, after the oscillation reaction, the water after the reaction can be filtered through a filter membrane to recover the catalyst.

[0037] Furthermore, the filter membrane may be a water filter membrane with a pore size of 0.45 μm.

[0038] The present invention also provides a heterogeneous Fenton reaction system.

[0039] Including Fenton reaction cell,

[0040] The Fenton reaction tank is provided with a partition component.

[0041] The partition component divides the Fenton reaction tank into a Fenton reaction zone and an effluent sedimentation zone;

[0042] The Fenton reaction zone is provided with a water inlet and a drug inlet;

[0043] The Fenton reaction zone is provided with a fixing component, a lifting component, and a catalyst loading component connected in sequence.

[0044] The catalyst supporting component is loaded with the Fenton catalyst prepared by the above preparation method or the above Fenton catalyst;

[0045] The water outlet sedimentation area is provided with a mud outlet and a water outlet.

[0046] Furthermore, the volume ratio of the Fenton reaction zone to the effluent sedimentation zone in the Fenton reaction tank is 4 to 2:1.

[0047] Furthermore, the catalyst supporting component is rotatably connected to the lifting component;

[0048] The catalyst supporting component is connected to a driving component.

[0049] Furthermore, the effluent sedimentation area is provided with a sludge collection component.

[0050] The sludge collecting component is connected to the partition component, and the sludge collecting component is connected to the sludge outlet.

[0051] Furthermore, the fixing component is a fixing rod, and both ends of the fixing rod are fixedly connected to the Fenton reaction tank.

[0052] Furthermore, an overflow weir is included, and the partition component is connected to the overflow weir.

[0053] Furthermore, the overflow weir is a rounded overflow weir, and the angle of the weir mouth of the rounded overflow weir is 60° to 80°.

[0054] Furthermore, the partition component is a partition, and the angle between the partition and the horizontal plane is 45° to 60°.

[0055] Furthermore, it also includes a water inlet tank and a reagent dosing component.

[0056] The water inlet tank is connected to the water inlet of the Fenton reaction zone;

[0057] The reagent dosing component is connected to the reagent inlet of the Fenton reaction zone.

[0058] Furthermore, the water outlet of the water outlet sedimentation area is connected to a drain pipe.

[0059] 3. Beneficial effects

[0060] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0061] (1) The preparation method of the Fenton catalyst provided by the present invention adopts a hydrothermal method, the preparation method is simple, the raw materials used are all cheap and readily available materials, and it is easy to prepare for large-scale production.

[0062] (2) The Fenton catalyst provided by the present invention, MIL-101(Fe) is loaded with VB2, which can promote the transfer of electrons and increase the Fe 3+ / Fe 2+ It improves the circulation efficiency and promotes the generation of more hydroxyl radicals to improve the degradation efficiency of organic pollutants in pharmaceutical wastewater in the Fenton reaction. It effectively solves the problems of low redox efficiency of the catalyst and substandard effluent quality, and has broad application prospects.

[0063] (3) The Fenton catalyst provided by the present invention can effectively degrade florfenicol in water in the method for degrading florfenicol in water, and the degradation rate can reach more than 95%, which has broad application prospects in the treatment of aquaculture tail water and antibiotic organic wastewater.

[0064] (4) The heterogeneous Fenton reaction system provided by the present invention can control the addition of Fenton catalyst and the start and end of the Fenton reaction, and ensure that pollutants in wastewater are fully degraded during the Fenton reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 This is a scanning electron microscope (SEM) image of the modified iron-based MOFs material VB2@MIL-101(Fe) in Example 1 of the present invention;

[0066] Figure 2 The X-ray diffraction XRD pattern of the modified iron-based MOFs material VB2@MIL-101(Fe) in Example 1 of the present invention;

[0067] Figure 3 It is a schematic diagram of the degradation of the modified iron-based MOFs material VB2@MIL-101(Fe) in Example 1 and the unmodified iron-based MOFs material MIL-101(Fe) in Comparative Example 1 containing 10 mg / L florfenicol drug solution;

[0068] Figure 4 The impedance test diagram is of the modified iron-based MOFs material VB2@MIL-101(Fe) in Example 1 of the present invention and the unmodified iron-based MOFs material MIL-101(Fe) in Comparative Example 1;

[0069] Figure 5 The impedance test diagram of the modified iron-based MOFs material VB2@MIL-101(Fe) in Examples 1-3 of the present invention and Comparative Example 2;

[0070] Figure 6 This is a schematic diagram of the three-dimensional structure of a heterogeneous Fenton reaction system in Example 4 of the present invention;

[0071] Figure 7 This is a schematic structural diagram of a heterogeneous Fenton reaction system in Example 4 of the present invention;

[0072] Figure 8 This is a schematic diagram of the structure of an operation room in Example 4 of the present invention;

[0073] Fig. 9 For the present invention Figure 6 Schematic diagram of the partial cross-sectional structure of an overflow weir.

[0074] Explanation of the symbols in the schematic diagram:

[0075] 100, Fenton reaction tank; 110, fixing component; 120, lifting component; 130, driving component; 140, catalyst loading component; 150, overflow weir; 151, supporting section; 152, overflow section; 153, buffer section; 160, partition component; 170, sludge collecting component; 180, second liquid conveying component;

[0076] 200, water inlet tank; 210, first liquid delivery component;

[0077] 300, operating room; 310, third liquid conveying component; 320, drug adding component; 330, water sample collecting component; 340, fourth liquid conveying component. DETAILED DESCRIPTION

[0078] The present disclosure may be more easily understood by reference to the following description in conjunction with examples, all of which constitute a part of the present disclosure. It should be understood that the present disclosure is not limited to the specific products, methods, conditions or parameters described and / or illustrated herein. Further, the terms used herein are only used for the purpose of describing specific embodiments by way of example and are not intended to be limiting unless otherwise indicated.

[0079] It should also be understood that, for the sake of clarity, certain features of the present disclosure may be described herein in the context of separate embodiments, but may also be provided in combination with each other in a single embodiment. That is, unless clearly incompatible or specifically not included, each separate embodiment is considered to be combinable with any other embodiment, and the combination is considered to represent another different embodiment. Conversely, for the sake of simplicity, the various features of the present disclosure described in the context of a single embodiment may also be provided individually or in any sub-combination. Finally, although a particular embodiment may be described as part of a series of steps or part of a more general structure, each step or substructure itself may also be considered to be an independent embodiment.

[0080] Unless otherwise indicated, it should be understood that each individual element in a list and each combination of individual elements in the list will be interpreted as a different embodiment. For example, a list of embodiments represented as "A, B, or C" should be interpreted to include embodiments "A", "B", "C", "A or B", "A or C", "B or C", or "A, B, or C".

[0081] In the present disclosure, the singular forms of the articles "a," "an," and "the" also include the corresponding plural references, and a reference to a specific value includes at least that specific value unless the context clearly indicates otherwise. Thus, for example, a reference to "a substance" is a reference to at least one of that substance and equivalents thereof.

[0082] When items are described by using the conjunction terms "... and / or...," etc., the description should be understood to include any one of the associated listed items and all combinations of one or more thereof.

[0083] In general, the use of the term "about" indicates an approximate value that can vary depending on the desired properties obtained by the disclosed subject matter, and will be interpreted in a context-dependent manner based on function. Therefore, one of ordinary skill in the art will be able to interpret a certain degree of difference on a case-by-case basis. In some cases, the number of significant figures used when expressing a particular value can be a representative technique for determining the difference allowed by the term "about". In other cases, a gradient in a range of values ​​can be used to determine the range of differences allowed by the term "about". Further, all ranges in this disclosure are inclusive and combinable, and reference to a value in a range includes each value within that range.

[0084] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs; the terms used herein and / or include any and all combinations of one or more of the associated listed items.

[0085] In the following examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if no manufacturer is specified, are all conventional products that can be purchased commercially.

[0086] The present invention is further described below in conjunction with specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art. The essential characteristics and remarkable effects of the present invention can be reflected from the following examples, and the described embodiments are part of the embodiments of the present invention, rather than all the embodiments, and therefore, they do not limit the present invention in any way, and those skilled in the art make some non-essential improvements and adjustments based on the content of the present invention, which all belong to the protection scope of the present invention.

[0087] Example 1

[0088] A method for preparing VB2-modified iron-based MOFs material is as follows:

[0089] (1) 5 mmol of ferric chloride hexahydrate (FeCl3·6H2O) and 2.5 mmol of terephthalic acid (H2BDC) were dissolved in 15 mL of N,N-dimethylformamide (DMF) to obtain a ferric chloride solution and a terephthalic acid solution;

[0090] (2) pouring the ferric chloride solution into the terephthalic acid solution, mixing and stirring for 30 minutes to obtain a mixed solution C;

[0091] (3) Weigh 0.2 mmol of riboflavin and dissolve it in mixed solution C. Mix and stir thoroughly for 60 min to form a homogeneous solution.

[0092] (4) The resulting homogeneous solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave and then heated at 110 °C for 20 h;

[0093] (5) The reaction solution was centrifuged at 4000 r / min for 15 min, washed three times with DMF and ethanol respectively, dried at 60 °C for 12 h, and then ground and collected with an agate mortar to obtain a brown-yellow solid, which is the VB2-modified iron-based MOFs material VB2@MIL-101(Fe), denoted as VB2-20@MIL-101(Fe).

[0094] Figure 1 The SEM image of the modified iron-based MOFs material VB2@MIL-101(Fe), i.e., the Fenton catalyst, prepared in this example is shown in FIG. Figure 1 It can be seen that the overall morphology structure of VB2-modified iron-based MOFs material is a regular octahedral crystal structure, and the particle size is between 500 and 600 nm.

[0095] Figure 2 The X-ray diffraction XRD pattern of the modified iron-based MOFs material VB2@MIL-101(Fe) prepared in this example. Figure 2 It can be seen that MIL-101(Fe) has characteristic diffraction peaks with high intensity at 2θ angles of 9.02°, 11.86°, 17.34°, and 21.82°, which indicates that MIL-101(Fe) has a high degree of crystallinity. In addition, the characteristic diffraction peaks of MIL-101(Fe) can be found in the X-ray diffraction pattern of VB2@MIL-101(Fe), and no other characteristic peaks appear when 2θ is at other angles. This shows that when VB2 is used to modify MIL-101(Fe), the crystal structure of MIL-101(Fe) itself is not destroyed, but VB2 is grafted onto the surface of the material. This shows that VB2 successfully modified MIL-101(Fe).

[0096] Example 2

[0097] A method for preparing VB2-modified iron-based MOFs material is as follows:

[0098] (1) 5 mmol of ferric chloride hexahydrate (FeCl3·6H2O) and 2.5 mmol of terephthalic acid (H2BDC) were dissolved in 15 mL of N,N-dimethylformamide (DMF) to obtain a ferric chloride solution and a terephthalic acid solution;

[0099] (2) pouring the ferric chloride solution into the terephthalic acid solution, mixing and stirring for 30 minutes to obtain a mixed solution C;

[0100] (3) Weigh 0.1 mmol of riboflavin and dissolve it in mixed solution C. Mix and stir thoroughly for 60 min to form a homogeneous solution.

[0101] (4) The resulting homogeneous solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave and then heated at 110 °C for 20 h;

[0102] (5) The reaction solution was centrifuged at 4000 r / min for 15 min, washed three times with DMF and ethanol respectively, dried at 60 °C for 12 h, and then ground and collected with an agate mortar to obtain a brown-yellow solid, which is the VB2-modified iron-based MOFs material VB2@MIL-101(Fe), denoted as VB2-10@MIL-101(Fe).

[0103] Example 3

[0104] A method for preparing VB2-modified iron-based MOFs material is as follows:

[0105] (1) 5 mmol of ferric chloride hexahydrate (FeCl3·6H2O) and 2.5 mmol of terephthalic acid (H2BDC) were dissolved in 15 mL of N,N-dimethylformamide (DMF) to obtain a ferric chloride solution and a terephthalic acid solution;

[0106] (2) pouring the ferric chloride solution into the terephthalic acid solution, mixing and stirring for 30 minutes to obtain a mixed solution C;

[0107] (3) Weigh 0.3 mmol of riboflavin and dissolve it in mixed solution C. Mix and stir thoroughly for 60 min to form a homogeneous solution.

[0108] (4) The resulting homogeneous solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave and then heated at 110 °C for 20 h;

[0109] (5) The reaction solution was centrifuged at 4000 r / min for 15 min, washed three times with DMF and ethanol respectively, dried at 60 °C for 12 h, and then ground and collected with an agate mortar to obtain a brown-yellow solid, which is the VB2-modified iron-based MOFs material VB2@MIL-101(Fe), denoted as VB2-30@MIL-101(Fe).

[0110] Comparative Example 1

[0111] A method for preparing an iron-based MOFs material is as follows:

[0112] (1) 5 mmol of ferric chloride hexahydrate (FeCl3·6H2O) and 2.5 mmol of terephthalic acid (H2BDC) were dissolved in 15 mL of N,N-dimethylformamide (DMF) to obtain a ferric chloride solution and a terephthalic acid solution;

[0113] (2) pouring the ferric chloride solution into the terephthalic acid solution, mixing and stirring for 30 minutes to obtain a mixed solution C;

[0114] (3) The resulting homogeneous solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave and then heated at 110 °C for 20 h;

[0115] (4) The reaction solution was centrifuged at 4000 r / min for 15 min, washed three times with DMF and ethanol respectively, dried at 60° C. for 12 h, and then ground and crushed with an agate mortar to obtain a brown solid, which is the iron-based MOFs material MIL-101 (Fe).

[0116] Comparative Example 2

[0117] A method for preparing VB2-modified iron-based MOFs material is as follows:

[0118] (1) 5 mmol of ferric chloride hexahydrate (FeCl3·6H2O) and 2.5 mmol of terephthalic acid (H2BDC) were dissolved in 15 mL of N,N-dimethylformamide (DMF) to obtain a ferric chloride solution and a terephthalic acid solution;

[0119] (2) pouring the ferric chloride solution into the terephthalic acid solution, mixing and stirring for 30 minutes to obtain a mixed solution C;

[0120] (3) Weigh 0.05 mmol of riboflavin and dissolve it in mixed solution C. Mix and stir thoroughly for 60 min to form a homogeneous solution.

[0121] (4) The resulting homogeneous solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave and then heated at 110 °C for 20 h;

[0122] (5) The reaction solution was centrifuged at 4000 r / min for 15 min, washed three times with DMF and ethanol respectively, dried at 60 °C for 12 h, and then ground and collected with an agate mortar to obtain a brown-yellow solid, which is the VB2-modified iron-based MOFs material VB2@MIL-101(Fe), denoted as VB2-5@MIL-101(Fe).

[0123] Figure 4 The impedance test graph shows that the conductivity of the modified iron-based MOFs material VB2-20@MIL-101(Fe) prepared in Example 1 is stronger than that of the unmodified iron-based MOFs material MIL-101(Fe), and can effectively reduce the impedance of MIL-101(Fe) from 179Ω / cm 2 Down to 136Ω / cm 2 , its conductivity is 16% higher than that of AQS (sodium anthraquinone-2-sulfonate)-MIL-101 (Fe). It should be noted that the preparation of AQS-MIL-101 (Fe) is the same as Example 1 in the Chinese patent document "Preparation method and application of modified iron-based MOFs" with publication number CN117186426A.

[0124] Combination Figure 5 The impedance of VB2-30@MIL-101(Fe) prepared in Example 3 is the smallest, which is 133Ω / cm 2 As the amount of VB2 added decreases, the impedance of the prepared VB2-modified iron-based MOFs material gradually increases.

[0125] The impedance test conditions are as follows: reference electrode: Ag / saturated AgCl electrode; counter electrode: Pt electrode; working electrode: glassy carbon electrode with the prepared catalyst material bonded to Nafion glue; electrolyte: 5.0mmol / L K3[Fe(CN)6] in 0.1mol / L KCl aqueous solution; the frequency range is set to 1-1×10 6 Hz, and the voltage amplitude is 5mV.

[0126] Application Examples

[0127] The VB2-20@MIL-101(Fe) prepared in Example 1 and the MIL-101(Fe) prepared in Comparative Example 1 are used as catalysts to degrade florfenicol in water. The specific applications are as follows:

[0128] (1) 0.04 g of the catalyst was added to 100 mL of water containing 10 mg / L florfenicol, and 10 mmol / L of hydrogen peroxide (H2O2) oxidant was added, and the Fenton reaction began.

[0129] (2) The solution was shaken thoroughly for reaction, and water samples were taken at 0, 0.5, 1, 1.5, 2, 2.5, and 3 h, respectively. 0.2 mol / L sodium thiosulfate (Na2S2O3) quencher was added to terminate the Fenton reaction, and the solution was filtered using a 0.45 μm water filter membrane.

[0130] (3) The filtered water sample was collected and placed in a brown liquid chromatography vial, and the florfenicol concentration in the water sample was detected by high performance liquid chromatography (HPLC), and the degradation rate of florfenicol was calculated.

[0131] Figure 3 Schematic diagram of the degradation of the modified iron-based MOFs material VB2@MIL-101(Fe) modified by VB2 prepared in Example 1 and MIL-101(Fe) in Comparative Example 1 to a drug solution containing 10 mg / L florfenicol. The horizontal axis represents the reaction time, and the vertical axis represents the degradation of florfenicol (florfenicol real-time concentration / florfenicol initial concentration). It can be seen that the degradation rate of adding the modified material after 150 minutes of Fenton reaction is as high as 98% ± 0.7%, while the degradation rate of adding the modified material is only 83.5% ± 1.8%, which can be explained that the selection of modified iron-based MOFs material has a better catalytic effect than unmodified iron-based MOFs material as Fenton catalyst.

[0132] Example 4

[0133] Combination Figure 6 , Figure 7 The present invention also provides a heterogeneous Fenton reaction system, including a Fenton reaction tank 100, a partition component 160 is arranged in the Fenton reaction tank 100, and the partition component 160 divides the Fenton reaction tank 100 into a Fenton reaction zone and a water outlet sedimentation zone; the Fenton reaction zone is provided with a water inlet and a drug inlet; the Fenton reaction zone is provided with a fixed component 110, a lifting component 120, and a catalyst loading component 140 connected in sequence, and the catalyst loading component 140 is loaded with a Fenton catalyst, and the Fenton catalyst can be a Fenton catalyst prepared in any one of embodiments 1 to 3; the water outlet sedimentation zone is provided with a mud outlet and a water outlet. The wastewater can be aquaculture tail water, pharmaceutical wastewater or other wastewater containing organic pollutants.

[0134] Wastewater and Fenton reagent enter the Fenton reaction zone through the water inlet and the reagent inlet respectively, and the wastewater is treated by Fenton oxidation under the catalytic action of the Fenton catalyst loaded on the catalyst loading component 140. The lifting component 120 can control the lifting and lowering of the catalyst loading component 140. For example, when the wastewater needs to be subjected to Fenton oxidation treatment, the catalyst loading component 140 can be lowered to immerse it in the wastewater, and the Fenton catalyst on the catalyst loading component 140 can play a catalytic role. After the Fenton oxidation treatment of the wastewater is completed, the catalyst loading component 140 can be lifted to separate it from the wastewater. After being separated from the wastewater, it is also convenient to replace the catalyst loading component 140.

[0135] When the water level in the Fenton reaction zone exceeds the highest position of the partition member 160, the treated wastewater flows into the effluent sedimentation zone. The treated wastewater also contains sludge, which settles in the effluent sedimentation zone and is discharged from the Fenton reaction tank 100 through the sludge outlet.

[0136] As an optional implementation, the Fenton catalyst can be dispersed in glue, and then the glue mixed with the catalyst is coated on the catalyst supporting component 140. In this process, the loading amount of the catalyst can be reasonably controlled.

[0137] Furthermore, the volume ratio of the Fenton reaction zone to the effluent sedimentation zone in the Fenton reaction tank 100 is 4 to 2:1, which is conducive to the wastewater fully reacting in the Fenton reaction zone to meet the discharge standard. As a preferred embodiment, the volume ratio of the Fenton reaction zone to the effluent sedimentation zone is 4:1.

[0138] Further, the catalyst loading component 140 is rotatably connected to the lifting component 120, and the catalyst loading component 140 can be rotated so that the Fenton catalyst is fully contacted with the wastewater, and the hydrogen peroxide can be fully mixed, which is conducive to a more complete Fenton reaction. On the other hand, the catalyst loading component 140 is connected to the driving component 130, and the catalyst loading component 140 can be driven to rotate by the driving component 130. For example, the catalyst loading component 140 and the lifting component 120 can be connected to a rotating shaft, and the driving component 130 can drive the catalyst loading component 140 to rotate through the rotating shaft.

[0139] As an optional embodiment, the effluent sedimentation area is provided with a sludge collecting component 170, which is connected to the partition component 160, and the sludge collecting component 170 is connected to the mud outlet. The sludge collecting component 170 is a sludge hopper, one side of which is connected to the partition component 160, and the sludge can slide from the partition component 160 into the sludge hopper, and then be discharged from the Fenton reaction tank 100 through the mud outlet. As another optional embodiment, the lower end of the partition component 160 is connected to the upper end of one side of the sludge collecting component 170, and the Fenton reaction tank 100 is divided into a Fenton reaction area and an effluent sedimentation area, and the internal structure of the Fenton reaction tank 100 will be more compact.

[0140] Specifically, the fixed component 110 is a fixed rod, and the two ends of the fixed rod are fixedly connected to the Fenton reaction tank 100; the lifting component 120 can be a telescopic rod or a lift; the driving component 130 can be a motor; the catalyst load component 140 is a material plate of corrosion-resistant material, such as a material plate of polytetrafluoroethylene material, to extend its service life, and the shape of the catalyst load component 140 can be rectangular, rhombus, etc. The catalyst load component 140 can also be provided with a number of small holes, the aperture of the small holes is less than 500nm, which increases its air permeability, is conducive to improving the reaction efficiency and reducing the resistance during rotation. As a specific embodiment, the upper end of the lift is connected to the fixed rod, the lower end is connected to the motor, the output shaft of the motor is connected to one side of the rectangular material plate, and the other side corresponding to the rectangular material plate can be connected to the motor by another set of fixed rods and lifts. In addition, the rotation direction of different material plates can be controlled separately by the motor connected thereto.

[0141] Furthermore, combined with Fig. 9 , the Fenton reaction zone also includes an overflow weir 150, which is arranged in the Fenton reaction zone, and the partition component 160 is connected to the overflow weir 150, so that the treated wastewater overflows from the Fenton reaction zone to the effluent sedimentation zone. Specifically, the overflow weir 150 includes a smooth buffer section 153 connected to the sludge collection component 170 so that the sludge enters the sludge collection component 170 at a lower speed, and the other side is a support section 151 for supporting the overflow weir 150, and the support section 151 can be fixedly connected to the Fenton reaction tank 100; it also includes an overflow section 152 in the middle part, and the top of the overflow section 152 is provided with a weir, and the overflow section 152 also includes an inclined surface, and the partition component 160 is connected to the inclined surface. As a specific embodiment, the overflow weir 150 is a rounded overflow weir 150, and the angle of the weir of the rounded overflow weir 150 is 60° to 80°, so that the sludge can slide down along the partition component 160 under the action of gravity and settle to the effluent sedimentation zone. The partition member 160 is a partition made of corrosion-resistant material, for example, a partition made of polytetrafluoroethylene. The angle between the partition and the horizontal plane is 45° to 60°, which is also conducive to the sludge sliding down along the partition under the action of gravity.

[0142] The heterogeneous Fenton reaction system further comprises a water inlet tank 200 and a reagent dosing component 320, wherein the water inlet tank 200 is connected to the water inlet of the Fenton reaction zone, the reagent dosing component 320 is connected to the reagent inlet of the Fenton reaction zone, the water inlet tank 200 is filled with collected wastewater, and the reagent dosing component 320 is filled with Fenton reagent, which can be respectively delivered to the Fenton reaction zone through the first liquid delivery component 210 and the third liquid delivery component 310, for example, both of which can be metering pumps, and the delivery amount can also be controlled. Specifically, the reagent dosing component 320 can be a reagent cylinder.

[0143] As an optional embodiment, the outlet of the effluent sedimentation area is connected to a drain pipe, and a second liquid delivery component 180 is provided on the drain pipe, such as a centrifugal pump or other water pump, which can extract the treated wastewater in the effluent sedimentation area and deliver it to the outside, such as to a sewage pipe network. As another optional embodiment, a drain pipe can be connected from the top of the effluent sedimentation area and delivered to the outside through the second liquid delivery component 180.

[0144] Furthermore, the water outlet sedimentation area is also provided with a detection port, which is connected to the water sample collection component 330. A fourth liquid delivery component 340, such as a metering pump, can be provided between the detection port and the water sample collection component 330 to extract a small amount of treated wastewater for detecting various water quality data. On the other hand, the water sample collection component 330 can be connected to a TOC integrated cabinet, and the TOC integrated cabinet can detect the quality of the treated wastewater in real time. Specifically, the water sample collection component 330 can be a water sample cartridge.

[0145] The heterogeneous Fenton reaction system also includes an intelligent operation table, which is electrically connected to the TOC integrated cabinet and the third liquid delivery component 310, the first liquid delivery component 210 and other liquid delivery components, and can automatically control the dosage of Fenton reagents, the flow rate of wastewater, etc. according to the real-time detection data of the TOC integrated cabinet. Figure 8 In order to facilitate the integration of automatic control, the intelligent operation table, the TOC integrated cabinet, the water sample collection component 330, the drug adding component 320, the third liquid delivery component 310, and the fourth liquid delivery component 340 can be concentrated in the same operation room 300. In addition, fire fighting equipment and the like can be set in the operation room 300.

[0146] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a Fenton catalyst, characterized in that: A solution containing ferric chloride hexahydrate, terephthalic acid and riboflavin is subjected to a hydrothermal reaction to obtain a Fenton catalyst VB2@MIL-101(Fe); The temperature of the hydrothermal reaction is 110-150°C and the time is 20-24h; The molar ratio of the ferric chloride hexahydrate, terephthalic acid and riboflavin is 2:1:(0.1-0.6).

2. The method for preparing the Fenton catalyst according to claim 1, wherein: The molar ratio of the ferric chloride hexahydrate, terephthalic acid and riboflavin is 2:1:(0.2-0.3).

3. The method for preparing the Fenton catalyst according to any one of claims 1 or 2, characterized in that: The ratio of ferric chloride hexahydrate to solvent in the solution is 5 mmol: (30-50) mL; The solvent of the solution includes N,N-dimethylformamide.

4. A Fenton catalyst prepared by the preparation method according to any one of claims 1 to 3, characterized in that: The Fenton catalyst comprises MIL-101(Fe), and riboflavin is loaded on the MIL-101(Fe).

5. The Fenton catalyst according to claim 4, characterized in that: The crystal structure of the Fenton catalyst is a regular octahedral structure; The particle size of the Fenton catalyst is 500-600 nm.

6. A method for degrading florfenicol in water using a Fenton catalyst prepared by the preparation method according to any one of claims 1 to 3 or a Fenton catalyst according to any one of claims 4 to 5, characterized in that: The Fenton catalyst is added into a water body containing florfenicol, and then hydrogen peroxide is added to carry out a shaking reaction.

7. The method for degrading florfenicol in water using the Fenton catalyst according to claim 6, characterized in that: The dosage of the Fenton catalyst is 0.2-0.5 g / L; The concentration of florfenicol in the water containing florfenicol is 1 to 50 mg / L; The dosage of the hydrogen peroxide is 10 to 30 mmol / L.

8. A heterogeneous Fenton reaction system, characterized in that: It comprises a Fenton reaction pool (100), wherein a partition component (160) is arranged in the Fenton reaction pool (100), and the partition component (160) divides the Fenton reaction pool into a Fenton reaction zone and an effluent sedimentation zone; The Fenton reaction zone is provided with a water inlet and a drug inlet; The Fenton reaction zone is provided with a fixing component (110), a lifting component (120), and a catalyst supporting component (140) which are connected in sequence. The catalyst supporting component (140) is supported with a Fenton catalyst prepared by the preparation method described in any one of 1 to 3 or a Fenton catalyst described in any one of claims 4 to 5; The water outlet sedimentation area is provided with a mud outlet and a water outlet.

9. The heterogeneous Fenton reaction system according to claim 8, characterized in that: The volume ratio of the Fenton reaction zone to the effluent precipitation zone is 4 to 2:1; The catalyst supporting component (140) is rotatably connected to the lifting component (120); The catalyst supporting component (140) is connected to a driving component (130).

10. The heterogeneous Fenton reaction system according to claim 9, characterized in that: The effluent sedimentation area is provided with a sludge collecting component (170). The sludge collecting component (170) is connected to the partition component (160), and the sludge collecting component (170) is connected to the sludge outlet; and / or, It also includes an overflow weir (150), and the partition component (160) is connected to the overflow weir (150).

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