A FeCo-NC catalyst, its preparation method and application, and a method for degrading antibiotics.

Abstract

This invention provides an FeCo-N-C catalyst, its preparation method, its application, and a method for degrading antibiotics. The FeCo-N-C catalyst of this invention not only efficiently activates recalcitrant organic pollutants (PAA) but also exhibits excellent regeneration performance and stability. Under conditions of 25°C, pH 7.0, catalyst dosage of 0.5 g / L, and an initial PAA concentration of 100 μM, the degradation rate of sulfamethoxazole reaches 91.5% within 90 minutes. Even in the presence of various anions and humic acids, the catalytic system of this invention maintains high degradation efficiency. After four cycles, the degradation efficiency of the FeCo-N-C catalyst remains above 70%. This invention provides a novel and environmentally friendly solution for the efficient treatment of recalcitrant organic pollutants.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and in particular to an FeCo-NC catalyst, its preparation method and application, and a method for degrading antibiotics. Background Technology

[0002] Sulfamethoxazole is a common antibiotic widely used in medicine and aquaculture. However, with the widespread use of antibiotics, antibiotic pollution has become one of the major threats to water pollution. Due to its persistent nature, sulfamethoxazole remains in the aquatic environment for a long time, posing a potential threat to the ecological environment and human health.

[0003] Traditional water treatment methods have limited effectiveness in removing antibiotic-like pollutants. In recent years, peracetic acid (PAA), as a highly efficient oxidant, has attracted widespread attention in wastewater treatment. PAA has shown good performance in degrading recalcitrant organic pollutants, and the byproducts produced after degradation are relatively harmless. However, the slow reaction rate of PAA and its corrosiveness at high concentrations limit its effectiveness in practical applications. Therefore, developing efficient catalytic materials to accelerate PAA activation has become a research hotspot. Summary of the Invention

[0004] This invention provides an FeCo-NC catalyst, its preparation method and application, and a method for degrading sulfamethoxazole. The aim is to degrade antibiotics such as sulfamethoxazole (SMX) in water by activating peracetic acid (PAA). The catalyst has excellent PAA activation performance and can maintain good degradation effect over a wide pH range. It can even efficiently degrade SMX in complex water environments (such as those containing multiple anions and humic acids).

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a method for preparing a FeCo-NC catalyst, comprising the following steps:

[0007] The ferrous salt was dissolved in water, and then polyvinylpyrrolidone was added to obtain a mixture.

[0008] An aqueous solution of K3[Co(CN)6] was added to the mixture, and the reaction was carried out at 80-90℃. The mixture was filtered, the solid was collected, dried, and calcined under an inert atmosphere to obtain the FeCo-NC catalyst.

[0009] Preferably, the calcination temperature is 700–850℃ and the time is 1.5–2.5h.

[0010] Preferably, an aqueous solution of K3[Co(CN)6] is added to the mixture, and the reaction is carried out at 80-90°C for 20-25 hours. The mixture is then filtered, the solid is collected, dried, and calcined under an inert atmosphere to obtain the FeCo-NC catalyst.

[0011] Preferably, the ferrous salt is FeCl2·4H2O, and the mass-to-volume ratio of FeCl2·4H2O, polyvinylpyrrolidone, water, and K3[Co(CN)6] aqueous solution is (0.03~0.04)g:(0.5~0.7)g:(20~25)mL:(20~25)mL.

[0012] Preferably, the inert atmosphere includes at least one of nitrogen, helium, argon, and neon.

[0013] Preferably, the concentration of the K3[Co(CN)6] aqueous solution is 0.05–0.1 mol / L.

[0014] Secondly, the present invention also provides an FeCo-NC catalyst, which is prepared by the preparation method described above.

[0015] Thirdly, the present invention also provides an application of the FeCo-NC catalyst prepared by the preparation method described above, or the FeCo-NC catalyst described above, in the degradation of antibiotics in water.

[0016] Preferably, the present invention also provides a method for degrading antibiotics, comprising the following steps:

[0017] The FeCo-NC catalyst prepared by the above preparation method or the FeCo-NC catalyst itself is added to wastewater containing antibiotics, and peracetic acid is added to the wastewater at the same time.

[0018] The FeCo-NC catalyst degrades antibiotics in wastewater by activating peracetic acid.

[0019] Preferably, in the step of adding the FeCo-NC catalyst to wastewater containing antibiotics and simultaneously adding peracetic acid to the wastewater, the concentration of the FeCo-NC catalyst in the wastewater is 100-500 mg / L, the concentration of peracetic acid in the wastewater is 50-200 μM, and the pH of the wastewater is 3-9.

[0020] The antibiotics include at least one of sulfamethoxazole, tetracycline, ciprofloxacin, and quinolones.

[0021] The FeCo-NC catalyst, its preparation method, its application, and the method for degrading antibiotics of the present invention have the following advantages over the prior art:

[0022] 1. The FeCo-NC catalyst of this invention is a nitrogen-doped carbon-based composite material with excellent catalytic performance. Compared with traditional carbon nanotube catalysts, the FeCo-NC catalyst not only possesses outstanding activity, but also, due to its unique magnetic properties, can be easily recovered by an external magnetic field, reducing operating costs and improving its feasibility in industrial applications;

[0023] 2. The FeCo-NC catalyst of the present invention can significantly improve the activity of PAA, enabling it to degrade antibiotics such as sulfamethoxazole in a shorter time, and is suitable for practical water treatment applications;

[0024] 3. The FeCo-NC catalyst of the present invention has a wide range of applications: the catalytic system exhibits good degradation effect in the pH range of 3 to 9, and can still maintain high efficiency in degradation when complex water components such as anions and humic acid are present.

[0025] 4. The FeCo-NC catalyst of the present invention has good regeneration performance: the catalyst can still maintain a high degradation efficiency after multiple cycles, and has good stability and regenerability, thus reducing the cost of use;

[0026] 5. The FeCo-NC catalyst of this invention is environmentally friendly and safe: the byproducts produced after the degradation of peracetic acid are water, acetic acid and carbon dioxide, which are non-toxic and harmless and meet environmental protection requirements. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 The image shows a scanning electron microscope (SEM) image of the FeCo-NC catalyst prepared in Example 1.

[0029] Figure 2 EDS surface scan of the FeCo-NC catalyst prepared in Example 1;

[0030] Figures 3-4 This is a high-resolution transmission electron microscope (HRTEM) image of the FeCo-NC catalyst prepared in Example 1;

[0031] Figure 5 The images show the XRD patterns of the FeCo-NC catalyst prepared in Example 1 before the reaction and the FeCo-NC catalyst recovered after the reaction according to the method in Example 2.

[0032] Figure 6 The Raman spectrum of the FeCo-NC catalyst prepared in Example 1;

[0033] Figure 7 The X-ray photoelectron spectroscopy (XPS) spectra of the FeCo-NC catalyst prepared in Example 1 before the reaction and the FeCo-NC catalyst recovered after the reaction according to the method in Example 2 are shown.

[0034] Figure 8 The specific surface area and pore size distribution of the FeCo-NC catalyst prepared in Example 1;

[0035] Figure 9 The effects of wastewater pH, peracetic acid concentration, and FeCo-NC catalyst concentration on the degradation of sulfamethoxazole were investigated.

[0036] Figure 10 For different anions Cl - SO4 2- NO 3- HCO 3- Effects on the degradation of sulfamethoxazole;

[0037] Figure 11 The effect of humic acid (HA) on the degradation of sulfamethoxazole;

[0038] Figure 12 The results are from the experiment in Example 1, where the FeCo-NC catalyst was used 1 to 4 times under optimal experimental conditions. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of embodiments. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single digits within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.

[0041] This application provides a method for preparing a FeCo-NC catalyst, comprising the following steps:

[0042] S1. Dissolve the ferrous salt in water, then add polyvinylpyrrolidone to obtain a mixture;

[0043] S2. Add K3[Co(CN)6] aqueous solution to the mixture, react at 80-90℃, filter, collect the solid, dry it, and calcine it under an inert atmosphere to obtain the FeCo-NC catalyst.

[0044] In some embodiments, the calcination temperature is 700–850°C and the time is 1.5–2.5 h.

[0045] In some embodiments, an aqueous solution of K3[Co(CN)6] is added to the mixture, and the mixture is reacted at 80-90°C for 20-25 hours. The mixture is then filtered, the solid is collected, dried, and calcined under an inert atmosphere to obtain the FeCo-NC catalyst.

[0046] In some embodiments, the ferrous salt is FeSO4, FeCl2, Fe(NO3)2, etc., preferably FeCl2·4H2O, and the mass-volume ratio of FeCl2·4H2O, polyvinylpyrrolidone, water, and K3[Co(CN)6] aqueous solution is (0.03~0.04)g:(0.5~0.7)g:(20~25)mL:(20~25)mL.

[0047] In some embodiments, the concentration of the K3[Co(CN)6] aqueous solution is 0.05 to 0.1 mol / L, preferably 0.05 mol / L.

[0048] In some embodiments, the inert atmosphere includes at least one of nitrogen, helium, argon, and neon.

[0049] The FeCo-NC catalyst of this invention is a nitrogen-doped carbon-based composite material with excellent catalytic performance. Compared with traditional carbon nanotube catalysts, the FeCo-NC catalyst not only possesses superior activity, but also, due to its unique magnetic properties, can be easily recovered by an external magnetic field, reducing operating costs and improving its feasibility in industrial applications.

[0050] Based on the same inventive concept, the present invention also provides an FeCo-NC catalyst, which is prepared by the above-described preparation method.

[0051] Based on the same inventive concept, the present invention also provides the application of the FeCo-NC catalyst prepared by the above preparation method or the above FeCo-NC catalyst in the degradation of antibiotics such as sulfamethoxazole in water.

[0052] The FeCo-NC catalyst of this invention degrades antibiotics such as sulfamethoxazole (SMX) in water by activating peracetic acid (PAA). This catalyst exhibits excellent PAA activation performance, maintaining good degradation efficiency across a wide pH range, and even efficiently degrading SMX in complex aquatic environments (such as those containing multiple anions and humic acids). Experimental verification shows that the FeCo-NC catalyst of this invention, under conditions of 25°C, pH 7.0, catalyst dosage of 0.5 g / L, and an initial PAA concentration of 100 μM, can increase the SMX degradation rate to 91.5% within 90 minutes. Furthermore, after four cycles of use, the catalyst's degradation efficiency remains above 70%, demonstrating good regeneration capacity and stability.

[0053] Based on the same inventive concept, the present invention also provides a method for degrading antibiotics, comprising the following steps:

[0054] The FeCo-NC catalyst prepared by the above method was added to wastewater containing antibiotics, and peracetic acid was added to the wastewater at the same time.

[0055] FeCo-NC catalysts degrade antibiotics such as sulfamethoxazole in wastewater by activating peracetic acid.

[0056] In some embodiments, in the step of adding FeCo-NC catalyst to wastewater containing antibiotics and simultaneously adding peracetic acid to the wastewater, the concentration of FeCo-NC catalyst in the wastewater is 100–500 mg / L, the concentration of peracetic acid in the wastewater is 50–200 μM, and the pH of the wastewater is 3–9.

[0057] In some embodiments, the antibiotic includes at least one of sulfamethoxazole, tetracycline, ciprofloxacin, quinolones, etc.

[0058] Specifically, in the above embodiments, the pH value of the wastewater was adjusted by adding H2SO4 or NaOH. The specific reaction temperature was room temperature (25℃) and the time was 5 to 90 minutes. The concentration of antibiotics such as sulfamethoxazole in the wastewater after the reaction was determined by LC-16 high performance liquid chromatography (HPLC).

[0059] The FeCo-NC catalyst of this invention can significantly improve the activity of PAA, enabling it to degrade antibiotics such as sulfamethoxazole in a shorter time, making it suitable for practical water treatment applications.

[0060] The FeCo-NC catalyst of the present invention has a wide range of applications: the catalytic system exhibits good degradation effect in the pH range of 3 to 9, and can still maintain high degradation efficiency in the presence of complex water components such as anions and humic acids.

[0061] The FeCo-NC catalyst of the present invention has good regeneration performance: the catalyst can still maintain high degradation efficiency after multiple cycles, and has good stability and regenerability, thus reducing the cost of use.

[0062] The FeCo-NC catalyst of this invention is environmentally friendly and safe: the byproducts produced after the degradation of peracetic acid are water, acetic acid and carbon dioxide, which are non-toxic and harmless and meet environmental protection requirements.

[0063] The following specific embodiments further illustrate the FeCo-NC catalyst of this application, its preparation method, its application, and a method for degrading antibiotics. This section further illustrates the content of the present invention with reference to specific embodiments, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in the art.

[0064] Example 1

[0065] This application provides a method for preparing a FeCo-NC catalyst, comprising the following steps:

[0066] S1. Dissolve 0.0357g FeCl2·4H2O in 20mL of ultrapure water and add 0.6g polyvinylpyrrolidone (PVP) to obtain a mixture;

[0067] S2. Add 20 mL of 0.05 mol / L K3[Co(CN)6] (potassium cobalt cyanide, purchased from Maclean's Reagent Company) aqueous solution to the mixture at a rate of 0.8 mL / min, and react vigorously in a water bath at 85 °C for 20 hours. After the reaction is complete, filter the supernatant, collect the solid, wash it three times with deionized water, and then dry it overnight at 60 °C. Finally, calcine the solid product in a tube furnace under a nitrogen atmosphere at 800 °C for 2 hours to obtain the FeCo-NC catalyst.

[0068] Example 2

[0069] This embodiment provides a method for degrading sulfamethoxazole, including the following steps:

[0070] S1. Prepare 100 mL of wastewater containing 10 μM sulfamethoxazole, and adjust the pH of the wastewater to 3-9 by adding H2SO4 or NaOH.

[0071] S2. The FeCo-NC catalyst prepared in Example 1 is added to the wastewater containing sulfamethoxazole in S1, and peracetic acid is added to the wastewater at the same time. The time is 5 to 90 minutes at room temperature (25°C).

[0072] The concentration of FeCo-NC catalyst in the wastewater is 100–500 mg / L, and the concentration of peracetic acid in the wastewater is 50–200 μM.

[0073] After the reaction was completed, the concentration of sulfamethoxazole in the wastewater after the reaction was determined using an LC-16 high-performance liquid chromatograph (HPLC).

[0074] Catalyst characterization

[0075] Figure 1 This is a scanning electron microscope (SEM) image of the FeCo-NC catalyst prepared in Example 1.

[0076] Figure 2 This is an EDS surface scan of the FeCo-NC catalyst prepared in Example 1.

[0077] Figures 3-4 This is a high-resolution transmission electron microscope (HRTEM) image of the FeCo-NC catalyst prepared in Example 1.

[0078] from Figures 1-4 It can be seen that the FeCo-NC catalyst prepared by this invention has a spherical structure, a smooth surface, uniform element distribution, and corresponding crystal lattice planes.

[0079] The XRD patterns of the FeCo-NC catalyst prepared in Example 1 before the reaction and the FeCo-NC catalyst recovered after the reaction according to the method in Example 2 are shown in the figure. Figure 5 As shown. The specific reaction conditions were: initial sulfamethoxazole concentration in the wastewater was 10 μM, wastewater pH was 7, reaction temperature was 25℃, reaction time was 90 min, FeCo-NC catalyst concentration in the wastewater was 500 mg / L, and peracetic acid concentration in the wastewater was 100 μM.

[0080] from Figure 5 As can be seen from the results, the structure of the FeCo-NC catalyst remained unchanged before and after the reaction, demonstrating the structural stability of the catalyst. The main crystal planes are all present. The diffraction peak at 23° belongs to the (002) crystal plane of graphite carbon (PDF#49-1721); the diffraction peaks at 44.5°, 64.5°, 82.2° and 99.1° belong to the (110), (200), (211) and (220) crystal planes of FeCo alloy, respectively (PDF#44-1433).

[0081] Figure 6 The Raman spectrum of the FeCo-NC catalyst prepared in Example 1; Figure 6 The presence of sp2 and sp3 carbon networks in the catalyst material was demonstrated. Both the D-peak and G-peak are Raman characteristic peaks of C atomic crystals, occurring at 1300 cm⁻¹. -1 and 1580cm -1 Nearby, the D peak represents defects in the C atom lattice, the G peak represents the in-plane stretching vibration of the C atom sp2 hybridization, and I(D) / I(G) is the intensity ratio of the D peak and the G peak, where I represents intensity. The I(D) / I(G) ratio of this catalyst is 1.17.

[0082] The X-ray photoelectron spectroscopy (XPS) spectra of the FeCo-NC catalyst prepared in Example 1 before the reaction and the FeCo-NC catalyst recovered after the reaction according to the method in Example 2 were tested. The results are as follows: Figure 7 As shown; where, Figure 7 In the text, "Fresh" indicates before the reaction and "Used" indicates after the reaction. The specific reaction conditions are as follows: the initial concentration of sulfamethoxazole in the wastewater is 10 μM, the pH value of the wastewater is 7, the reaction temperature is room temperature (25℃), the reaction time is 90 min, the concentration of FeCo-NC catalyst in the wastewater is 500 mg / L, and the concentration of peracetic acid in the wastewater is 100 μM.

[0083] from Figure 7As can be seen, both the FeCo-NC catalyst before and after the reaction contain the four elements Fe, Co, N, and C. The N 1s spectrum shows four peaks at 398.7, 399.6, 400.6, and 402.1 eV, which are attributed to pyridine N, pyridine N, graphitic N, and N oxide, respectively. The high-resolution Co 2p spectrum is divided into two parts: Co 2p3 / 2 and Co 2p1 / 2 spin orbitals. Within the Co 2p3 / 2 range, the typical peaks observed at 779.6, 781.2, 783.2, and 786.8 eV correspond to Co, respectively. 0 Co 3+ Co 2+ And satellites. In the Co2p1 / 2 spectrum, the peaks centered at 796.7 and 798.4 eV correspond to Co, respectively. 2+ and Co 3+ Additionally, the Co 2p peak at 803.5 eV is attributed to a satellite peak. The high-resolution Fe 2p spectrum was fitted to six peaks, encompassing the two portions of the spin orbitals of Fe 2p3 / 2 and Fe 2p1 / 2. The two peaks at 720.3 eV are satellite peaks in FeCo@NC, while the two pairs of peaks at 711.1 / 723.7 and 713.5 / 726.3 eV represent Fe... 2+ and Fe 3+ The XPS results for the FeCo-NC catalyst after the reaction were similar, with only the proportions of N, Fe, Co, and C species changing.

[0084] Figure 8 The specific surface area and pore size distribution of the FeCo-NC catalyst prepared in Example 1 were determined by the Brenner-Emmett-Teller (BET) method.

[0085] Figure 8 Based on the N2 adsorption-desorption isotherm, the BET specific surface area of ​​the catalyst was calculated to be 73 m². 2 / g, and the presence of mesopores, which play a crucial role in enhancing catalytic activity by promoting mass transfer between the substrate and the oxidant.

[0086] Following the method in Example 2, the effects of wastewater pH, peracetic acid concentration, and FeCo-NC catalyst concentration on the degradation of sulfamethoxazole were investigated. The results are as follows: Figure 9 As shown.

[0087] Specifically, Figure 9 In (a), the pH of the wastewater during the reaction was 3 to 9 (pH values ​​were 3, 5, 7, and 9, respectively), and the other conditions remained unchanged as follows: the initial concentration of sulfamethoxazole in the wastewater was 10 μM, the concentration of FeCo-NC catalyst in the wastewater was 500 mg / L, and the concentration of peracetic acid in the wastewater was 100 μM.

[0088] Figure 9 In (b), the concentration of peracetic acid during the reaction was 0–200 μM (0 μM, 50 μM, 100 μM, and 200 μM, respectively; 0 μM means no PAA), and the other conditions remained constant as follows: the initial concentration of sulfamethoxazole in the wastewater was 10 μM, the pH value of the wastewater was 7, and the concentration of FeCo-NC catalyst in the wastewater was 500 mg / L.

[0089] Figure 9 In (c), the concentration of FeCo-NC catalyst in the wastewater during the reaction was 0–500 mg / L (0 mg / L, 100 mg / L, 200 mg / L, and 500 mg / L, respectively; 0 mg / L means no catalyst), and the other conditions remained unchanged: the initial concentration of sulfamethoxazole in the wastewater was 10 μM, the pH value of the wastewater was 7, and the concentration of peracetic acid in the wastewater was 100 μM.

[0090] Figure 9 In (a) to (c), C is the concentration of sulfamethoxazole (SMX) in the wastewater at time t, and C0 is the concentration of sulfamethoxazole (SMX) in the wastewater at time 0 (i.e., at the initial time).

[0091] from Figure 9 As can be seen, pH has little effect on the degradation rate of SMX, meaning that the catalytic PAA technology can operate within a wide pH range; the degradation rate of SMX gradually increases with increasing catalyst dosage and PAA concentration.

[0092] Taking into account both cost and treatment efficiency, the optimal reaction conditions are: temperature 25℃, initial pH of wastewater 7.0, FeCo-NC catalyst dosage 0.5g / L, and initial peracetic acid (PAA) concentration 100μM; under these conditions, the degradation rate of 10μM SMX is 75% in 90 minutes.

[0093] Following the method described in Example 2, different anions Cl were studied. - SO4 2- NO 3- HCO 3- The effect on the degradation of sulfamethoxazole was as follows: Figure 10 As shown. Specifically, Cl - SO4 2- NO 3- HCO 3- It is added in the form of sodium salt, specifically by the following method:

[0094] S1. Prepare 100 mL of wastewater containing 10 μM sulfamethoxazole and adjust the pH of the wastewater to 7.

[0095] S2. The FeCo-NC catalyst prepared in Example 1 is added to the wastewater containing sulfamethoxazole in S1, while peracetic acid and Cl are added to the wastewater simultaneously. - (Added in the form of NaCl), the time is 5 to 90 minutes at room temperature (25℃);

[0096] The concentration of FeCo-NC catalyst in the wastewater was 500 mg / L, the concentration of peracetic acid in the wastewater was 100 μM, and the concentration of Cl in the wastewater was... - Concentrations range from 0 to 5 mM (0 mM, 0.05 mM, 0.5 mM, and 5 mM, respectively; 0 mM indicates no Cl). - );

[0097] After the reaction was completed, the concentration of sulfamethoxazole in the wastewater after the reaction was determined using an LC-16 high-performance liquid chromatograph (HPLC).

[0098] SO4 2- NO 3- HCO 3- The experimental method for the effect on the degradation of sulfamethoxazole was the same as above, except that NaCl was replaced by Na2SO4, NaNO3, and NaHCO3, respectively.

[0099] Figure 10 In this context, C is the concentration of sulfamethoxazole (SMX) in the wastewater at time t, and C0 is the concentration of sulfamethoxazole (SMX) in the wastewater at time 0 (i.e., initially).

[0100] from Figure 10 It can be seen from Cl - and 5mM SO4 2- The presence of [a substance] has a slight promoting effect on the degradation of SMX, while NO [is present]. 3- The presence of HCO3- at 0.05 mM and 0.5 mM has no effect on the degradation of SMX. 3- The presence of a significant inhibitory effect on the degradation of SMX indicates that this technology can cope with the influence of conventional ions.

[0101] Following the method in Example 2, the effect of humic acid (HA) on the degradation of sulfamethoxazole was studied, and the results are as follows: Figure 11 As shown. The specific method is as follows:

[0102] S1. Prepare 100 mL of wastewater containing 10 μM sulfamethoxazole and adjust the pH of the wastewater to 7.

[0103] S2. The FeCo-NC catalyst prepared in Example 1 is added to the wastewater containing sulfamethoxazole in S1. Peracetic acid and humic acid (HA) are added to the wastewater at the same time. The time is 5 to 90 minutes at room temperature (25°C).

[0104] The concentration of FeCo-NC catalyst in the wastewater is 500 mg / L, the concentration of peracetic acid in the wastewater is 100 μM, and the concentration of humic acid (HA) in the wastewater is 0–30 mg / L (the concentrations are 0 mg / L, 1 mg / L, 5 mg / L, 10 mg / L, and 30 mg / L, respectively; 0 mg / L means no humic acid (HA)).

[0105] After the reaction was completed, the concentration of sulfamethoxazole in the wastewater after the reaction was determined using an LC-16 high-performance liquid chromatograph (HPLC).

[0106] Figure 11 In this context, C is the concentration of sulfamethoxazole (SMX) in the wastewater at time t, and C0 is the concentration of sulfamethoxazole (SMX) in the wastewater at time 0 (i.e., initially).

[0107] from Figure 11 It can be seen that the presence of humic acid inhibits the degradation of SMX, and the more HA is added, the more obvious the inhibition rate is. However, when the amount added is above 10 mg / L, the inhibitory effect of HA does not increase with the increase of HA concentration.

[0108] Figure 12 The results are from the experiment conducted in Example 1, using the FeCo-NC catalyst in Example 2, under optimal experimental conditions for 1 to 4 cycles. The optimal conditions were: temperature 25°C, initial pH of wastewater 7.0, FeCo-NC catalyst dosage 0.5 g / L, and initial peracetic acid (PAA) concentration 100 μM.

[0109] Figure 12 In this context, C is the concentration of sulfamethoxazole (SMX) in the wastewater at time t, and C0 is the concentration of sulfamethoxazole (SMX) in the wastewater at time 0 (i.e., initially).

[0110] from Figure 12 It can be seen that the FeCo-NC catalyst exhibits stable SMX degradation performance after multiple cycles.

[0111] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of degrading an antibiotic, characterized by, The method comprises the following steps: adding the FeCo-N-C catalyst into wastewater containing antibiotics, and adding peracetic acid into the wastewater; the FeCo-N-C catalyst degrades the antibiotics in the wastewater by activating the peracetic acid; in the step of adding the FeCo-N-C catalyst into wastewater containing antibiotics, and adding peracetic acid into the wastewater, the concentration of the FeCo-N-C catalyst in the wastewater is 100-500 mg / L, the concentration of the peracetic acid in the wastewater is 50-200 μM, and the pH of the wastewater is 5-7; the antibiotics are sulfamethoxazole; a preparation method of the FeCo-N-C catalyst, comprising the following steps: dissolving a ferrous salt in water, and then adding polyvinylpyrrolidone to obtain a mixed solution; adding an aqueous solution of K3[Co(CN)6] into the mixed solution, reacting at 80-90 ℃, filtering, collecting the solid, and drying, and calcining under an inert atmosphere to obtain the FeCo-N-C catalyst; the calcining temperature is 700-850 ℃, and the calcining time is 1.5-2.5 h; the ferrous salt is FeCl2·4H2O, and the mass-volume ratio of FeCl2·4H2O, polyvinylpyrrolidone, water, and the aqueous solution of K3[Co(CN)6] is (0.03-0.04) g:(0.5-0.7) g:(20-25) mL:(20-25) mL; the concentration of the aqueous solution of K3[Co(CN)6] is 0.05-0.1 mol / L.

2. The method of degrading an antibiotic of claim 1, wherein, adding an aqueous solution of K3[Co(CN)6] into the mixed solution, reacting at 80-90 ℃ for 20-25 h, filtering, collecting the solid, and drying, and calcining under an inert atmosphere to obtain the FeCo-N-C catalyst.

3. The method of degrading an antibiotic of claim 1, wherein, the inert atmosphere comprises at least one of nitrogen, helium, argon, and neon.

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