Method for degrading antibiotic wastewater based on SR-AOPs mediated Fenton system

Abstract

The invention provides a method for degrading antibiotic wastewater based on an SR-AOPs mediated Fenton system, which comprises the following steps: putting a Fenton reaction Fe3O4-MXene catalytic material into antibiotic wastewater to construct a catalytic system, and activating persulfate to catalytically degrade the antibiotic wastewater for 0-30 minutes; the addition amount of the Fenton reaction Fe3O4-MXene catalytic material is 100-200 mg / L. A catalytic system which does not need to be additionally provided with H2O2 and an iron source and can produce H2O2 in situ is constructed, mixed reactive oxygen species (ROS) generated in the catalytic system is used for degrading antibiotic wastewater, the oxidation efficiency is high, the cost is low, and the stability is good; according to the catalytic material, Fe3O4 nanoparticles are integrated to interlayer and heterogeneous surfaces of MXene to form a double-catalytic-center structure, a Fe3O4-MXene heterostructure promotes sustainable redox cycle of Fe < 2 + > / Fe < 3 + > through electron transfer, O2 is reduced to generate H2O2, PMS is synergistically activated to generate hydroxyl radicals (OH) to drive efficient Fenton reaction, the preparation method is simple, the stability is good after multiple times of cycle use, and the catalytic material is suitable for industrial production. And secondary pollution can be avoided through magnetic recovery.

Description

Technical Field

[0002] The present invention belongs to the technical field of antibiotic wastewater treatment, and specifically relates to a method for degrading antibiotic wastewater based on an SR-AOPs-mediated Fenton system, a Fe3O4-MXene catalytic material for Fenton reaction and a preparation method thereof, and an antibiotic wastewater treatment agent. Background Art

[0004] Antibiotics pollute surface water and groundwater, and their antibacterial and stable properties make them difficult to degrade, threatening human health. Currently, conventional sewage biological methods cannot efficiently remove them. The Fenton reaction has received attention because it can generate highly reactive hydroxyl radicals (•OH) and efficiently degrade refractory organic pollutants.

[0005] In the traditional Fenton system, continuous external addition of H2O2 is required, which not only has high operating costs and complex operations, but also induces free radical quenching reactions due to excessive H2O2, reducing the oxidation efficiency. Moreover, the instability of H2O2 in the aqueous phase system makes it easily decompose into O2 and H2O, limiting the continuous progress of the Fenton reaction. In addition, the large-scale addition of H2O2 significantly increases the system operating costs and operation complexity.

[0006] Compared with •OH, the sulfate radical (SO4• - )in the advanced oxidation process based on sulfate radicals has a longer lifespan (30–40 μs, while •OH is only ~1 ns), and still maintains a high oxidation ability between pH 3-9. Activation of peroxymonosulfate (PMS) can simultaneously generate SO4• - and •OH, forming a "dual radical system", which can significantly improve the degradation efficiency of organic pollutants. Existing studies have shown that PMS-activated AOPs can degrade more than 90% of TC within a few minutes. However, the activation efficiency of PMS depends on the performance of the catalyst, and is usually activated by an electron transfer method using a reducing metal or transition metal carbide, oxide, carbon material, etc. However, the reaction conditions of the electron transfer method are harsh, requiring specific catalysts and reaction temperatures, and are prone to environmental pollution during the activation process. Therefore, finding efficient and stable catalysts remains the focus of current research. In recent years, many composites based on Cu, Ag, Fe, Co doping have been developed, which also improve the activation rate of persulfate. Heterogeneous Fe-based materials have been widely studied because they are environmentally friendly and have good electron transfer characteristics. However, the activation of persulfate on Fe-based materials is limited by the speed of the Fe 3+ / Fe 2+ redox reaction, resulting in a decrease in the activation rate of persulfate. Summary of the invention

[0008] In order to overcome the shortcomings of the above-mentioned prior art, the present invention constructs a catalytic system that can produce H2O2 in situ without the need for external H2O2 and iron source, a method for degrading antibiotic wastewater based on the SR-AOPs-mediated Fenton system with high oxidation efficiency, low cost and good stability, and also provides a Fenton reaction Fe3O4-MXene catalytic material and preparation method, and an antibiotic wastewater treatment agent.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] A method for degrading antibiotic wastewater based on a SR-AOPs-mediated Fenton system, wherein a Fenton reaction Fe3O4-MXene catalytic material is added into the antibiotic wastewater to construct a catalytic system, and activated persulfate is used to catalyze and degrade the antibiotic wastewater for 0 to 30 minutes; the dosage of the Fenton reaction Fe3O4-MXene catalytic material is 100 to 200 mg / L, and the concentration of the persulfate is 10 to 40 mg / L.

[0011] Preferably, the pH of the antibiotic wastewater is 3.53~11.01.

[0012] The present invention also provides a Fenton reaction Fe3O4-MXene catalytic material, wherein the catalytic material is formed by integrating Fe3O4 nanoparticles into the interlayer and heterogeneous surface of MXene to form a dual catalytic center structure, and the Fe3O4-MXene heterogeneous structure promotes Fe3O4 reaction through electron transfer. 2+ / Fe 3+ The sustainable redox cycle reduces O2 to generate H2O2 and synergistically activates PMS to generate hydroxyl radicals (•OH) to drive the efficient Fenton reaction.

[0013] The present invention also provides a method for preparing a Fe3O4-MXene catalytic material for a Fenton reaction, which is characterized by comprising the following steps:

[0014] (1) Sodium fluoride was added to the HF solution and magnetically stirred for 30 min, then Ti3AlC2 was added and stirred vigorously for 48 h, washed by centrifugation with deionized water, and freeze-dried for 48 h to obtain multilayer MXene;

[0015] (2) adding FeCl3-6H2O, polyethylene glycol, anhydrous sodium acetate and the multilayer MXene prepared in step (1) to a mixed solution of ethylene glycol and 1,2-propylene glycol in a volume ratio of 1:1 in sequence, and stirring the mixture by magnetic stirring for 2 hours to obtain a uniform suspension;

[0016] (3) Add the suspension in step (2) to an autoclave and react at 150 - 200 °C for 8 - 10 hours. After the reaction, wash, magnetically separate and dry to obtain the Fenton reaction Fe3O4-MXene catalytic material.

[0017] The present invention also provides an antibiotic wastewater treatment agent, which comprises the Fenton reaction Fe3O4-MXene catalytic material and persulfate mixed in a mass percentage of (10:1) - (15:4).

[0018] The antibiotics in the present invention are one or several mixed antibiotics of tetracycline, penicillin, amoxicillin, and ampicillin.

[0019] In the antibiotic wastewater of the present invention, the concentration of the antibiotic is not more than 50 mg / L. Theoretically, when the antibiotic concentration is greater than 50 mg / L, it is also applicable to the present invention, but only the dosages of the magnetic composite material Fe3O4-MXene and persulfate, as well as the degradation time, need to be adjusted.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. By integrating magnetic Fe3O4 nanoparticles into the interlayer and heterogeneous surface of MXene, the present invention constructs a novel Fe3O4-MXene heterostructure catalyst. This catalyst promotes the sustainable redox cycle of Fe 2+ / Fe 3+ through an electron transfer mechanism, realizes the efficient reduction of O2 to generate H2O2, and synergistically activates peroxymonosulfate (PMS) to generate hydroxyl radicals (•OH), thereby improving the efficiency of the Fenton reaction. Experimental results show that this system can achieve a degradation rate of 89% of tetracycline (TC) within 2.5 min. The reaction rate is six times higher than the degradation efficiency under the condition without PMS, and the oxidation efficiency is high. In addition, the in-situ generation amount of H2O2 reaches 42.669 mmol / L, and the degradation efficiency is equivalent to that of a traditional Fenton system that needs to externally add 50 mmol / L H2O2. Without the need to add H2O2, the operation is simple and the operating cost is reduced.

[0022] 2. For the Fenton reaction Fe3O4-MXene catalytic material of the present invention, the magnetic Fe3O4 nanoparticles provide Fe 2+ / Fe 3+ redox sites, and form an interfacial bridging structure of Fe 3+ -O-Ti 3+ through interfacial electron transfer (Ti³⁺→Fe 2+ -O-Ti 4+ with the Ti 2+-(OOSO3)-Ti 4+ - Transition state, significantly reducing its activation energy and increasing the regeneration rate of Fe 2+ .

[0023] 3. The electron donor property of MXene and the redox ability of Fe3O4 synergistically establish an efficient electron transfer channel, stabilizing the Fe(IV)=O intermediate. Under the condition of no external energy, Fe3O4 not only acts as an electron donor to reduce O2 to H2O2, but also catalyzes the generation of ·OH through continuous redox cycles (Fe 3+ / Fe 2+ ). Without adding external H2O2 and iron source, the operation is simple and the operation cost is reduced.

[0024] 4. The Fenton reaction Fe3O4-MXene catalytic material of the present invention has excellent stability and reusability. After five consecutive cycles, the catalyst can still maintain high degradation performance, and can be quickly recovered by magnetic separation technology, avoiding catalyst loss and secondary pollution in the traditional Fenton process. Description of the Drawings

[0026] Figure 1 is the electron microscope image of the Fe3O4-MXene catalytic material of the present invention;

[0027] Figure 2 is the treatment effect diagram of the Fe3O4-MXene catalytic material of the present invention and persulfate used alone and in combination for treating tetracycline antibiotic wastewater;

[0028] Figure 3 is the electron spin resonance spectrum of the Fe3O4-MXene catalytic material of the present invention synergistically catalyzing the reaction with persulfate;

[0029] Figure 4 is the treatment effect diagram of the Fe3O4-MXene catalytic material with different masses of the present invention synergistically with persulfate for treating tetracycline antibiotic wastewater;

[0030] Figure 5 Treatment effect diagram of the Fe3O4-MXene catalytic material of the present invention synergistically with different masses of persulfate (PMS) for treating tetracycline antibiotic wastewater;

[0031] Figure 6 is the treatment effect diagram of the Fe3O4-MXene catalytic material of the present invention synergistically with persulfate for treating tetracycline antibiotic wastewater under different pH conditions. Detailed Embodiments

[0033] ​The following further describes the specific embodiments of the present invention. It should be noted here that the descriptions of these embodiments are for helping to understand the present invention, but do not constitute a limitation to the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] The experimental methods in the following examples are all conventional methods unless otherwise specified, and the reagent materials used in the following examples can all be obtained through conventional commercial channels unless otherwise specified.

[0035] Example 1

[0036] The Fenton reaction Fe3O4-MXene catalytic material of the present invention is used in combination with persulfate (PMS) to treat antibiotic wastewater.

[0037] (1) Preparation of the Fenton reaction Fe3O4-MXene catalytic material

[0038] 2.04 g of FeCl3·6H2O, 4.5 g of polyethylene glycol, 12.0 g of anhydrous sodium acetate, and 0.19 g of MXene are added to a solution containing 120 m of ethylene glycol (EG) and 120 mL of 1,2-propanediol (PG). The mixture is magnetically stirred at 60 °C for 2 hours to obtain a uniform suspension, which is then added to an autoclave and reacted at 200 °C for 8 hours. After the reaction, it is washed, magnetically separated, and dried to obtain magnetic Fe3O4-MXene particles. Figure 1 , it can be seen that MXene presents an accordion structure with gaps, MXene etching is successful, Fe3O4 nanoparticles are embedded in the gaps of the MXene layer, with an obvious layered stacking structure, and the magnetism of the composite material is more stable.

[0039] (2) Oxidative degradation of tetracycline antibiotic wastewater

[0040] 45 mg of the Fe3O4-MXene (concentration of 150 mg / L) catalytic material is added to a solution containing 300 mL of tetracycline (solution pH = 7.46, the solution pH value is not adjusted). It is magnetically stirred for 30 min in the dark to reach the adsorption equilibrium, and then exposed to indoor natural light (about 0.198 mw / cm 2 ), 12 mg of persulfate (PMS) (concentration of 40 mg / L) is added. At regular intervals, 0.2 mL of the suspension is taken and filtered through a 0.22 μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, a high performance liquid chromatograph is used to analyze the residual antibiotic concentration.

[0041] As Figure 2As shown, under the conditions of adding 12 mg of persulfate (PMS) oxidant (concentration: 40 mg / L), 45 mg of Fe3O4-MXene catalyst (concentration: 150 mg / L), and a pH value of 7.46, the catalytic oxidation effect of Fe3O4-MXene on antibiotics is as Figure 2 shown. After 30 minutes of reaction, the removal rate of antibiotics reaches 92.46%. The reaction rate constant calculated by the reaction kinetic formula is 0.01334 min -1 .

[0042] (2) Detection of reactive oxygen species

[0043] Under the conditions of adding 12 mg of persulfate (PMS) oxidant (concentration: 40 mg / L) and 45 mg of Fe3O4-MXene catalyst (concentration: 150 mg / L), samples are taken after 2.5 minutes, 5 minutes, and 10 minutes of reaction. The radical scavengers DMPO (5,5-dimethyl-1-pyrroline-N-oxide) and TEMP (5-ethoxycarbonyl-5-methyl-1-pyrroline-N-oxide) are added, and the generation of free radicals is analyzed using an electron spin resonance spectrometer, as Figure 3 shown. The electron spin resonance spectrum shows the signals of hydroxyl radicals and sulfate radicals. With the increase of reaction time, the signal intensities of the characteristic peaks of DMPO(•OH) and DMPO(SO4• - ) increase significantly. The six-peak signal (1:1:1:1:1:1) of •OH can be clearly observed at 5 minutes of reaction in the system, while the characteristic peak of SO4•- remains at the three-peak signal at 10 minutes. It can be seen that with the progress of the reaction, the generated •OH radicals gradually increase and play a dominant role in the degradation process of tetracycline.

[0044] Example 2

[0045] The Fe3O4-MXene catalytic materials with different masses in the Fenton reaction of the present invention are used to treat antibiotic wastewater in combination with persulfate (PMS).

[0046] (1) The preparation of the Fe3O4-MXene catalytic material for the Fenton reaction is the same as that in Example 1.

[0047] (2) The optimal mass of the Fe3O4-MXene catalyst used in this example test.

[0048] (3) Oxidative degradation of tetracycline antibiotic wastewater.

[0049] 30 mg and 60 mg of Fe3O4-MXene (concentrations of 100 mg / L and 200 mg / L) catalytic materials were separately added to a solution containing 300 mL of tetracycline (solution pH = 7.46, and the solution pH value was not adjusted). Magnetic stirring was carried out for 30 min under dark conditions to reach the adsorption equilibrium, and then it was exposed to indoor natural light (0.198 mw / cm 2 or so). 12 mg of persulfate (PMS) (concentration of 40 mg / L) was added. Suspension of 0.2 mL was taken at regular intervals and filtered through a 0.22-μm PES hydrophilic filter. Formic acid water and acetonitrile were used as the mobile phase, and a high-performance liquid chromatograph was used to analyze the residual antibiotic concentration.

[0050] As Figure 4 shown, under the conditions of the dosages of 30 mg and 60 mg of Fe3O4-MXene catalysts (concentrations of 100 mg / L and 200 mg / L), 12 mg of persulfate (PMS) oxidant (concentration of 40 mg / L), and a pH value of 7.46, the catalytic oxidation effect of Fe3O4-MXene on antibiotics was as Figure 4 shown. After the reaction for 30 minutes, the removal rates of antibiotics were 80.01% and 76.23%, and the reaction rate constants calculated by the reaction kinetic formula were 0.00623 min -1 and 0.01097 min -1 .

[0051] Example 3

[0052] The present invention was used to treat antibiotic wastewater by using different masses of persulfate (PMS) in combination with Fe3O4-MXene catalytic materials in the Fenton reaction.

[0053] (1) The preparation of the Fe3O4-MXene catalytic material for the Fenton reaction was the same as in Example 1.

[0054] (2) The optimal mass of persulfate (PMS) in this example was tested.

[0055] (3) Oxidative degradation of tetracycline antibiotic wastewater.

[0056] 45 mg of Fe3O4-MXene (concentration of 150 mg / L) catalytic material was added to a solution containing 300 mL of tetracycline (solution pH = 7.46, and the solution pH value was not adjusted). Magnetic stirring was carried out for 30 min under dark conditions to reach the adsorption equilibrium, and then it was exposed to indoor natural light (0.198 mw / cm 2Around (left and right), 3 mg, 6 mg, and 9 mg of persulfate (PMS) (concentrations of 10 mg / L, 20 mg / L, and 30 mg / L) were added respectively. Every once in a while, 0.2 mL of the suspension was taken and filtered through a 0.22-μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, a high-performance liquid chromatograph was used to analyze the concentration of the residual antibiotic.

[0057] As Figure 5 shown, under the conditions of the dosages of 3 mg, 6 mg, and 9 mg of persulfate (PMS) (concentrations of 10 mg / L, 20 mg / L, and 30 mg / L), 45 mg of the catalyst Fe3O4-MXene (concentration of 150 mg / L), and a pH value of 7.46, the catalytic oxidation effect of Fe3O4-MXene on the antibiotic was as Figure 5 shown. After reacting for 30 minutes, the removal rates of the antibiotic were 45.21%, 50.11%, and 62.35%. The reaction rate constants calculated through the reaction kinetic formula were 0.0011 min -1 , 0.0013 min -1 , 0.00381 min -1 .

[0058] Example 4

[0059] The Fenton reaction Fe3O4-MXene catalytic material of the present invention (without adding PMS) was used to treat the antibiotic wastewater.

[0060] (1) The preparation of the Fenton reaction Fe3O4-MXene catalytic material was the same as that in Example 1.

[0061] (2) Oxidative degradation of the tetracycline antibiotic wastewater

[0062] 45 mg of the Fe3O4-MXene catalytic material (concentration of 150 mg / L) was added to a solution containing 300 mL of tetracycline (solution pH = 7.46, and the solution pH value was not adjusted). It was magnetically stirred for 30 minutes under dark conditions to reach the adsorption equilibrium, and then exposed to indoor natural light (0.198 mw / cm 2 around). Every once in a while, 0.2 mL of the suspension was taken and filtered through a 0.22-μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, a high-performance liquid chromatograph was used to analyze the concentration of the residual antibiotic.

[0063] As Figure 2 shown, under the conditions of the dosage of 45 mg of the Fe3O4-MXene catalyst (concentration of 150 mg / L) and a pH value of 7.46, the catalytic oxidation effect of the prepared Fe3O4-MXene on tetracycline was as Figure 2As shown, after 30 minutes of reaction, the removal rate of tetracycline was 14.12%, and the reaction rate constant was calculated to be 0.00091 min -1 .

[0064] Example 5

[0065] The oxidation degradation of tetracycline antibiotic wastewater by the Fenton reaction Fe3O4-MXene catalytic material and the co-oxidant PMS of the present invention under different pH conditions.

[0066] (1) The preparation of the Fenton reaction Fe3O4-MXene catalytic material was the same as in Example 1.

[0067] (2) Oxidation degradation of tetracycline antibiotic wastewater

[0068] The pH values of the tetracycline solution containing 40 mg / L PMS were adjusted to 3.53, 5.33, 7.46 (the solution pH value was not adjusted), 9.01 and 11.01 with 0.1 M H2SO4 and NaOH, respectively. Then, 45 mg (concentration of 150 mg / L) of the catalyst Fe3O4-MXene prepared in Example 1 was weighed and added to the tetracycline solutions with different pH values (50 mg / L, 300 mL) under magnetic stirring to start the catalytic degradation reaction. After 30 min of reaction (sampling time: 2.5 min, 5 min, 10 min, 15 min, 20 min, 30 min), 0.2 mL of the suspension was taken with a syringe at regular intervals and filtered through a 0.22 μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, a high performance liquid chromatograph was used to detect and analyze the residual tetracycline concentration.

[0069] Under the condition of the dosage of 12 mg PMS co-oxidant (concentration of 40 mg / L) and 45 mg Fe3O4-MXene catalyst (concentration of 150 mg / L), the catalytic oxidation effect of the prepared Fe3O4-MXene and co-oxidant PMS on tetracycline wastewater at different pH values was as Figure 6 shown. When the pH value was 3.53 and 5.33, the removal rate of tetracycline decreased to 71.12% and 58.65%, and the reaction rate constant was 0.00622 min -1 , 0.00382 min -1 . When the pH value rose to 7.46 and 9.01, the removal rate of tetracycline increased to 92.36% and 86.36%, and the reaction rate constant was 0.01334 min -1 . When the pH value was 11.01, the degradation rate of tetracycline decreased to 65.95%, and the reaction rate constant was 0.0019 min -1 .

[0070] Example 6

[0071] The yield of H2O2 in the catalytic reaction of the Fenton reaction Fe3O4-MXene catalytic material and the co-oxidant PMS of the present invention under different environments.

[0072] (1) The preparation of the Fenton reaction Fe3O4-MXene catalytic material was the same as in Example 1.

[0073] (2) The yield of H2O2 in the catalytic reaction under different environments

[0074] The electrochemical workstation was used to measure the H2O2 yield of different catalysts in the catalytic reaction of tetracycline. The current response method was used to measure the H2O2 yield in the system. Based on the standard curve of H2O2 and the current response curve, the H2O2 yields under different environments ("oxygen-rich, normal") were calculated. The order of H2O2 yields under different environments was oxygen-rich > normal (the catalytic system was Fe3O4-MXene / PMS), and the corresponding yields were 62.956 and 42.699 mmol / L respectively.

[0075] Control Example 1

[0076] Treat antibiotic wastewater with the oxidant persulfate PMS.

[0077] (1) Weigh 12 mg of persulfate PMS with a concentration of 40 mg / L;

[0078] (2) Under magnetic stirring, add 12 mg of persulfate PMS (concentration 40 mg / L) to 300 ml of tetracycline solution (solution pH = 7.46, solution pH value not adjusted), and stir magnetically for 30 min in the dark to reach adsorption equilibrium, and then expose it to indoor natural light (about 0.198 mw / cm 2 ). Take 0.2 mL of the suspension at regular intervals and filter it with a 0.22 μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, a high performance liquid chromatograph was used to analyze the residual tetracycline concentration.

[0079] Under the dosing amount of 12 mg of PMS oxidant (concentration 40 mg / L) and the pH value of 7.46, the catalytic oxidation effect of persulfate on tetracycline in this control example was as Figure 2 shown. After reacting for 30 minutes, the removal rate of tetracycline with an initial concentration of 50 mg / L was 22.1%, and the reaction rate constant was calculated to be 0.00834 min -1 .

[0080] Control Example 2

[0081] Treatment of antibiotic wastewater with magnetic Fe3O4 nanomaterials.

[0082] (1) Weigh 45 mg of magnetic Fe3O4 nanoparticles (concentration: 150 mg / L);

[0083] (2) Removal of tetracycline antibiotic wastewater by magnetic Fe3O4 catalyst;

[0084] Under magnetic stirring, add 45 mg of magnetic Fe3O4 nanoparticles (concentration: 150 mg / L) to 300 mL of tetracycline solution (solution pH = 7.46, solution pH value not adjusted). Stir magnetically for 30 min in the dark to reach adsorption equilibrium, and then expose it to indoor natural light (about 0.198 mw / cm 2 ). Take 0.2 mL of the suspension at regular intervals and filter it with a 0.22 μm PES hydrophilic filter. Use formic acid water and acetonitrile as the mobile phase, and analyze the residual tetracycline concentration by high performance liquid chromatography.

[0085] Under the conditions of a dosage of 45 mg of magnetic Fe3O4 catalyst (concentration: 150 mg / L) and a pH value of 7.46, the removal effect of magnetic Fe3O4 catalyst on tetracycline wastewater in this control example is as Figure 2 shown. After reacting for 30 minutes, the removal rate of tetracycline with an initial concentration of 50 mg / L is 6.26%.

[0086] Control Example 3

[0087] Treatment of antibiotic wastewater with a multi-layer MXene catalyst.

[0088] (1) Preparation of the catalyst

[0089] Add sodium fluoride to the HF solution and stir magnetically for 30 min. Then add Ti3AlC2 and stir vigorously for 48 hours. Centrifuge and wash with deionized water, and freeze-dry for 48 hours to obtain multi-layer MXene.

[0090] (2) Oxidative degradation of tetracycline antibiotic wastewater

[0091] Under magnetic stirring, add 45 mg of multi-layer MXene catalyst (concentration: 150 mg / L) to 300 mL of tetracycline solution (solution pH = 7.46, solution pH value not adjusted). Stir magnetically for 30 min in the dark, and then expose it to indoor natural light (about 0.198 mw / cm 2 ). Take 0.2 mL of the suspension at regular intervals and filter it with a 0.22 μm PES hydrophilic filter. Use formic acid water and acetonitrile as the mobile phase, and analyze the residual tetracycline concentration by high performance liquid chromatography.

[0092] Under the conditions of adding 45 mg of multi-layer MXene catalyst (concentration 150 mg / L) and a pH value of 7.46, the removal effect of the multi-layer MXene catalyst on tetracycline wastewater in this control example is as Figure 2 shown. After reacting for 30 minutes, the removal rate of tetracycline with an initial concentration of 50 mg / L is 47.27%.

[0093] Control Example 4

[0094] Mix the above Control Examples 2 and 3 with persulfate PMS respectively for synergistic treatment of antibiotic wastewater.

[0095] (1) Weigh 45 mg of magnetic Fe3O4 nanoparticles and multi-layer MXene (both with a concentration of 150 mg / L) and 12 mg of persulfate PMS (concentration 40 mg / L).

[0096] (2) The removal of tetracycline antibiotic wastewater by magnetic Fe3O4 catalyst and multi-layer MXene in synergy with persulfate (PMS) respectively

[0097] Under magnetic stirring, add 45 mg each of magnetic Fe3O4 nanoparticles and multi-layer MXene (both with a concentration of 150 mg / L) into 300 mL of tetracycline solution (solution pH = 7.46, solution pH value not adjusted) respectively. Stir magnetically for 30 min in the dark to reach adsorption equilibrium, then expose to indoor natural light (about 0.198 mw / cm 2 ), and then add persulfate (PMS) with a concentration of 40 mg / L respectively. Take 0.2 mL of the suspension at regular intervals and filter it with a 0.22 μm PES hydrophilic filter. Using formic acid water and acetonitrile as the mobile phase, analyze the residual tetracycline concentration by high performance liquid chromatography.

[0098] Under the conditions of adding 45 mg each of magnetic Fe3O4 nanoparticles and multi-layer MXene (both with a concentration of 150 mg / L) and a pH value of 7.46, the removal effect of magnetic Fe3O4 nanoparticles and multi-layer MXene in synergy with persulfate (PMS) on tetracycline wastewater in this control example is as Figure 2 shown. After reacting for 30 minutes, the removal rates of tetracycline with an initial concentration of 50 mg / L are 83.31% and 86.23% respectively.

[0099] In the Fenton reaction of the Fe3O4-MXene catalytic material of the present invention for synergistic treatment of antibiotic wastewater with PMS, the activation of persulfate on the Fe-based material will not be affected by Fe 3+ / Fe 2+The limitation of the rate of redox reaction has achieved unexpected effects in improving the activation rate of persulfate. The present invention does not require the addition of H2O2 and iron source, and the catalytic system that can in-situ produce H2O2 has high oxidation efficiency, low cost and good stability, and is worthy of popularization and application.

[0100] The above has described the embodiments of the present invention in detail, but the present invention is not limited to the described embodiments. For those skilled in the art, without departing from the principle and spirit of the present invention, various changes, modifications, substitutions and variations made to these embodiments still fall within the protection scope of the present invention.

Claims

1. A method for degrading antibiotic wastewater based on the Fenton system mediated by SR-AOPs, characterized in that: The Fenton reaction Fe3O4-MXene catalytic material is added into antibiotic wastewater to construct a catalytic system, and the activated persulfate is used to catalyze the degradation of the antibiotic wastewater for 30 minutes; the dosage of the Fenton reaction Fe3O4-MXene catalytic material is 100~200 mg / L, and the concentration of the persulfate is 10~40 mg / L.

2. The method according to claim 1, characterized in that The pH value of the antibiotic wastewater is 3.53-11.

01.

3. A Fenton reaction Fe3O4-MXene catalytic material, characterized in that: The catalytic material is composed of Fe3O4 nanoparticles integrated into the interlayer and heterogeneous surface of MXene to form a dual catalytic center structure. The Fe3O4-MXene heterogeneous structure promotes Fe 2+ / Fe 3+ The sustainable redox cycle reduces O2 to generate H2O2 and synergistically activates PMS to generate hydroxyl radicals (•OH) to drive the efficient Fenton reaction.

4. The method for preparing the Fenton reaction Fe3O4-MXene catalytic material according to claim 3, characterized in that: The following steps are involved: (1) Sodium fluoride was added to the HF solution and magnetically stirred for 30 min, then Ti3AlC2 was added and stirred vigorously for 48 h, washed by centrifugation with deionized water, and freeze-dried for 48 h to obtain multilayer MXene; (2) adding FeCl3-6H2O, polyethylene glycol, anhydrous sodium acetate and the multilayer MXene prepared in step (1) to a mixed solution of ethylene glycol and 1,2-propylene glycol in a volume ratio of 1:1 in sequence, and stirring the mixture by magnetic stirring for 2 hours to obtain a uniform suspension; (3) Add the suspension of step (2) into an autoclave and react at 150-200° C. for 8-10 hours. After the reaction is completed, wash, magnetically separate and dry to obtain a Fenton reaction Fe3O4-MXene catalytic material.

5. An antibiotic wastewater treatment agent, characterized in that: The Fenton reaction Fe3O4-MXene catalytic material is mixed with persulfate in a mass percentage of (10:1) to (15:4).

6. The method according to claim 1 or 2 or the antibiotic wastewater treatment agent according to claim 5, characterized in that: The antibiotic is one or a mixture of tetracycline, penicillin, amoxicillin and ampicillin.

Images