Treatment method and treatment device for antibiotic wastewater

Abstract

The invention relates to the technical field of industrial wastewater treatment, and particularly discloses a treatment method and a treatment device for antibiotic wastewater. The treatment method comprises the following steps: simultaneously introducing ozone gas and antibiotic wastewater into a microbubble generator to obtain ozone microbubble wastewater; the ozone microbubble wastewater and a Fe / Ti3C2 / TiO2 catalyst are added into an ultraviolet reactor for catalytic oxidation reaction, and treated wastewater is obtained. Through the coupling process design of ozone microbubbles cooperating with Fe / Ti3C2 / TiO2 catalysis and specific wavelength ultraviolet oxidation, thorough treatment of antibiotics difficult to degrade is achieved, the removal rate of antibiotics in wastewater reaches 99% or above, the removal rate of TOC reaches 69% or above, the method can adapt to antibiotics with different concentrations, and the method is suitable for industrial production. The problems of low efficiency of traditional biological treatment, high cost of advanced oxidation, secondary pollution of an adsorption method and the like are solved, and the method has high efficiency, environmental protection property and industrial potential.

Description

Technical Field

[0001] This invention relates to the field of industrial wastewater treatment technology, and in particular to a method and apparatus for treating antibiotic wastewater. Background Technology

[0002] Ciprofloxacin, a third-generation quinolone broad-spectrum antibacterial drug, is widely used in medicine, animal husbandry, aquaculture, and other fields due to its excellent antibacterial activity, broad spectrum, and good oral absorption. With the continuous expansion of ciprofloxacin's application and the increasing usage, the amount of wastewater discharged during its production and use is also increasing. Because ciprofloxacin contains a stable piperazine ring and fluorine atoms in its molecular structure, it exhibits strong chemical stability and biotoxicity, making it difficult to effectively degrade using conventional biological treatment methods.

[0003] Currently, methods for treating ciprofloxacin wastewater mainly include physical adsorption, advanced oxidation, and biological treatment. While physical adsorption is simple to operate and low in cost, it only transfers pollutants and cannot completely degrade them. Furthermore, once the adsorbent is saturated, subsequent treatment is required, which can easily cause secondary pollution. Advanced oxidation methods, such as Fenton oxidation and ozone oxidation, can effectively degrade ciprofloxacin, but they suffer from demanding reaction conditions (e.g., requiring specific pH values ​​and temperatures), large reagent dosages, high operating costs, and the potential generation of toxic byproducts, making large-scale industrial application difficult. Traditional biological treatment methods utilize the metabolic activity of microorganisms to degrade pollutants; however, ciprofloxacin has a strong inhibitory effect on microorganisms, leading to reduced microbial activity, low treatment efficiency, and difficulty in meeting wastewater discharge standards.

[0004] Therefore, developing an efficient, stable treatment method for ciprofloxacin wastewater with different concentrations is of great importance for reducing ciprofloxacin pollution of the water environment and protecting the ecological environment. Summary of the Invention

[0005] To address the problems of poor treatment efficiency and inability to consistently meet discharge standards in existing antibiotic wastewater treatment methods, this invention provides a method and apparatus for treating antibiotic wastewater. This invention employs microbubble ozone catalytic oxidation technology, using a Fe / Ti3C2 / TiO2 catalyst under ultraviolet irradiation to treat antibiotic wastewater. This results in an antibiotic degradation rate exceeding 99% and a TOC removal rate exceeding 69%, with stable treatment performance, demonstrating broad application prospects in the field of antibiotic wastewater treatment.

[0006] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows: A method for treating antibiotic wastewater includes the following steps: Ozone gas and antibiotic wastewater to be treated are simultaneously introduced into a microbubble generator to obtain ozone microbubble wastewater; ozone microbubble wastewater and Fe / Ti3C2 / TiO2 catalyst are added to an ultraviolet reactor for catalytic oxidation reaction to obtain treated wastewater; In the Fe / Ti3C2 / TiO2 catalyst, the Fe atoms are Fe 3+ ; The ultraviolet reactor is equipped with several ultraviolet lamps arranged in parallel inside, and the wavelength of the ultraviolet lamps is 252nm~256nm.

[0007] Compared to existing technologies, the antibiotic wastewater treatment method provided by this invention achieves highly efficient degradation of antibiotic wastewater through the combined use of specific wavelength ultraviolet light, ozone microbubble technology, and a Fe / Ti3C2 / TiO2 catalyst via a multi-mechanism synergistic effect. Specifically, ultraviolet light directly photolyzes water molecules to generate highly oxidizing hydroxyl radicals (‧OH), and simultaneously promotes the conversion of ozone into active free radical precursors (H2O2). H2O2 further reacts with photogenerated holes to generate ‧OH, significantly increasing the concentration of ‧OH in the system through multiple pathways, thereby more efficiently destroying the chemical structure of antibiotics. Ozone microbubbles, with their slow rise rate, long lifespan, and large specific surface area, significantly improve the gas-liquid mass transfer rate, solving the problem of low mass transfer efficiency in traditional ozone aeration. They also autonomously generate ‧OH upon contraction and rupture, providing stronger oxidizing power. Simultaneously, ozone microbubbles increase the oxygen content of the solution and alter the light propagation path, creating a more favorable environment for the interaction between ultraviolet light and the catalyst.

[0008] Meanwhile, the Fe / Ti3C2 / TiO2 catalyst exhibits excellent photocatalytic performance. The doping of Fe and Ti3C2 narrows the band gap of TiO2, thereby enhancing the light absorption capacity and photogenerated carrier generation efficiency of the catalyst. At the same time, Ti3C2 has high metal-like electrical conductivity, which promotes the migration of photogenerated electrons from TiO2 to Ti3C2. Furthermore, the Schottky junction formed by the two effectively suppresses the recombination of photogenerated electron-hole pairs, further improving the separation and utilization efficiency of photogenerated electron-hole pairs.

[0009] In summary, the antibiotic wastewater treatment method provided by this invention can not only significantly improve the degradation efficiency and shorten the degradation time of antibiotic wastewater, but also increase the mineralization rate of wastewater, reduce intermediate products and product toxicity, and significantly improve ozone utilization and reduce costs. It has important practical significance for efficiently solving the problem of antibiotic wastewater treatment, developing a circular economy, and protecting the ecological environment.

[0010] It should be noted that microbubble technology refers to increasing the gas-liquid contact area by generating bubbles with a diameter of less than 50 μm, thereby improving the efficiency of gas transfer into water. At the same time, microbubbles can also enhance the flotation effect and help remove oil and suspended solids from water.

[0011] In one specific embodiment of the present invention, the antibiotic wastewater is ciprofloxacin wastewater.

[0012] As a specific embodiment of the present invention, the preparation method of the Fe / Ti3C2 / TiO2 catalyst includes the following steps: Nano-titanium dioxide and soluble iron salt were dissolved in deionized water, stirred in the dark, and the solid and liquid were separated, washed, and dried to obtain the Fe / TiO2 catalyst. The Fe / TiO2 catalyst and Ti3C2 were added to anhydrous ethanol, mixed evenly, and subjected to a solvothermal reaction at 150℃~200℃. After solid-liquid separation, washing and drying, the Fe / Ti3C2 / TiO2 catalyst was obtained.

[0013] The preparation method of the Fe / Ti3C2 / TiO2 catalyst provided by this invention first involves stirring soluble iron salt and nano-titanium dioxide in deionized water in the dark to achieve Fe... 3+ Uniform loading on the TiO2 surface and light-protected conditions can prevent premature photocatalytic reactions in TiO2 that could lead to Fe... 3+ The adsorption is unstable; at a specific temperature, a solvothermal reaction promotes the formation of a tight composite structure between Ti3C2 and TiO2. The stable Schottky junction can effectively suppress the recombination of photogenerated electron-hole pairs, ensuring the photocatalytic activity of the catalyst in the UV-coupled ozone microbubble system.

[0014] The Fe / Ti3C2 / TiO2 catalyst provided by this invention uses readily available raw materials and does not involve the use of toxic solvents, which is beneficial for industrial production applications.

[0015] Furthermore, the mass ratio of the nano-titanium dioxide to the soluble iron salt is 20:1 to 25:1.

[0016] The optimal mass ratio ensures Fe 3+ It is uniformly attached to the TiO2 surface in a monodisperse or oligomeric state, and Fe 3+ It forms a stable adsorption and binding state with the TiO2 surface, ensuring sufficient active sites while avoiding agglomeration problems, thus laying the foundation for the efficient distribution of active sites for the subsequent composite of the catalyst with Ti3C2 and the photocatalytic performance.

[0017] Specifically, the soluble iron salt is ferric nitrate.

[0018] Furthermore, the mass-to-volume ratio of the soluble iron salt to deionized water is 1 g: (110~130) mL.

[0019] Furthermore, the stirring time in the dark is 20-25 hours, and the temperature is 25-30°C.

[0020] Optimal stirring temperature and time are beneficial for Fe 3+ It forms a stable bond with the adsorption sites on the TiO2 surface, thereby improving the stability of the catalyst.

[0021] Furthermore, the mass ratio of the Fe / TiO2 catalyst to Ti3C2 is 80:1 to 120:1.

[0022] The optimized mass ratio ensures that Ti3C2 is uniformly dispersed on the Fe / TiO2 surface, while avoiding obstruction of the Fe / TiO2 surface. 3+ Under the premise of active sites and TiO2 light absorption sites, the density of Schottky junctions should be increased as much as possible to lay the structural foundation for synergistic enhancement of catalytic activity.

[0023] Furthermore, the mass-to-volume ratio of the Fe / TiO2 catalyst to anhydrous ethanol is 1 g: (15~20) mL.

[0024] Furthermore, the solvothermal reaction time is 24h~36h.

[0025] As a specific embodiment of the present invention, the method for preparing Ti3C2 includes the following steps: LiF was added to hydrochloric acid solution and reacted at 40℃~45℃ for 15min~20min. Then Ti3AlC2 was added and the reaction was continued at 40℃~45℃ for 45h~50h. After solid-liquid separation, the mixture was freeze-dried and ground to obtain Ti3C2.

[0026] First, a stable etching system is generated by the LiF-hydrochloric acid reaction, and then Ti3AlC2 is added for etching. This avoids local over-etching caused by Ti3AlC2 directly contacting the high concentration of etchant, and preserves the layered structure of Ti3C2 completely, ensuring unobstructed electron transport channels when it is combined with Fe / TiO2 catalyst in the future.

[0027] Furthermore, the mass-to-volume ratio of LiF to hydrochloric acid solution is (1.5~2) g:20 mL, and the concentration of hydrochloric acid solution is 8 mol / L~10 mol / L.

[0028] Furthermore, the mass ratio of LiF to Ti3AlC2 is 1.5:1 to 2:1.

[0029] Furthermore, the freeze-drying temperature is -70℃ to -80℃.

[0030] Vacuum freeze drying can effectively prevent Ti3C2 aggregation and maintain the dispersed state of Ti3C2 layers.

[0031] Furthermore, the gas-to-water volume ratio of the microbubble generator is 1:5 to 1:10, and the inlet pressure of the microbubble generator is 0.25 MPa to 0.5 MPa.

[0032] Furthermore, the ultraviolet lamp has a power of 15W~20W, a current of 0.1A~0.15A, and a frequency of 50Hz~60Hz.

[0033] Furthermore, the catalytic oxidation reaction takes 60 to 90 minutes.

[0034] Furthermore, the mass-to-volume ratio of the Fe / Ti3C2 / TiO2 catalyst to the antibiotic wastewater to be treated is (7~8) g:15L.

[0035] Secondly, the present invention also provides an apparatus for treating antibiotic wastewater, comprising an ozone generator, a microbubble generator, and an ultraviolet reactor connected in sequence; wherein the inlet of the microbubble generator is connected to the upper part of the ultraviolet reactor, and the outlet is connected to the bottom of the ultraviolet reactor.

[0036] In one specific embodiment of the present invention, the ultraviolet reactor includes a reactor body and a plurality of ultraviolet lamps arranged in parallel inside the reactor body; the ultraviolet lamps are immersed in the antibiotic wastewater to be treated within the reactor body.

[0037] In one specific embodiment of the present invention, a gas flow meter is provided between the ozone generator and the microbubble generator to control the gas-to-water ratio entering the microbubble generator.

[0038] The antibiotic wastewater treatment method provided by this invention achieves thorough treatment of recalcitrant antibiotic wastewater through a coupled process design of ozone microbubbles synergistically with Fe / Ti3C2 / TiO2 catalysis and specific wavelength ultraviolet oxidation. The removal rate of antibiotics in the wastewater reaches over 99%, and the TOC removal rate reaches over 69%. It can be adapted to antibiotic wastewater of different concentrations and solves the pain points of traditional biological treatment such as low efficiency, high cost of advanced oxidation, and secondary pollution of adsorption methods. It has the advantages of high efficiency, environmental protection and industrialization potential, and is of great significance to energy conservation, emission reduction and circular economy development. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the apparatus used in an embodiment of the present invention for treating ciprofloxacin wastewater; Figure 2 This is a TEM image of TiO2 used in Embodiment 1 of the present invention; Figure 3 This is a TEM image of Ti3C2 prepared in Example 1 of the present invention; Figure 4 This is a TEM image of the Fe / Ti3C2 / TiO2 catalyst prepared in Example 1 of this invention; Figure 5 The XRD patterns of the Ti3AlC2, Ti3C2, TiO2 and Fe / Ti3C2 / TiO2 catalysts in Example 1 of this invention are shown below. Figure 6 This is a comparison diagram of the bandgap widths of TiO2 and Fe / Ti3C2 / TiO2 in Example 1 of the present invention. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] A schematic diagram of the apparatus for treating ciprofloxacin wastewater used in this embodiment of the invention is shown below. Figure 1 As shown, it includes an oxygen cylinder, an ozone generator, a microbubble generator, and an ultraviolet reactor connected in sequence. The ultraviolet reactor is filled with an Fe / Ti3C2 / TiO2 catalyst. The inlet of the microbubble generator is connected to the upper part of the ultraviolet reactor, and the outlet is connected to the bottom of the ultraviolet reactor. The microbubble generator and the ultraviolet reactor form a circulation path.

[0042] Specifically, the ultraviolet reactor includes a reactor body and two ultraviolet lamps disposed inside the reactor body, with the two ultraviolet lamps arranged in parallel and symmetrically.

[0043] In one specific embodiment of the present invention, the ultraviolet light has a wavelength of 252~256nm, a power of 15~20W, a current of 0.1~0.15A, and a frequency of 50~60Hz.

[0044] In one specific embodiment of the present invention, a gas flow meter is provided between the ozone generator and the microbubble generator to control the gas-to-water ratio entering the microbubble generator.

[0045] In one specific embodiment of the present invention, the outlet of the ultraviolet reactor is connected to a KI absorption bottle to absorb unreacted oxygen or excess ozone.

[0046] In one specific embodiment of the present invention, the ultraviolet reactor is also connected to a condenser for cooling the ciprofloxacin wastewater. The ozone catalytic oxidation of ciprofloxacin wastewater releases heat; therefore, a condenser is installed to cool the wastewater, ensuring a suitable reaction temperature and the safety of the treatment process.

[0047] The method for treating ciprofloxacin wastewater using the above-mentioned device specifically includes the following steps: Oxygen is introduced into the ozone generator, and the generated ozone gas and ciprofloxacin wastewater are simultaneously introduced into the microbubble generator. The ozone-microbubble wastewater enters the reactor from the bottom of the ultraviolet reactor. Under the irradiation of ultraviolet lamps, enhanced mass transfer by microbubbles, and the action of Fe / Ti3C2 / TiO2 catalysts, ozone efficiently oxidizes and degrades the pollutants in the ciprofloxacin wastewater. After the reaction, the exhaust gas is discharged from the reactor and then the residual ozone is absorbed by another KI absorption bottle to prevent environmental pollution, and finally the exhaust gas meets the emission standards.

[0048] To better illustrate the present invention, further examples are provided below.

[0049] Example 1 This invention provides a method for preparing a Fe / Ti3C2 / TiO2 catalyst, the specific steps of which are as follows: Step a: Add 3.2g LiF and 40mL 9M HCl solution to a polytetrafluoroethylene-lined reactor. Place the reactor in a heat-collecting constant-temperature magnetic stirrer and adjust the water bath temperature to 40℃. React under these conditions for 15min. Weigh 2g Ti3AlC2 and slowly add it to the reactor in small amounts. Adjust the reactor speed to 500rpm and react at 40℃ for 48h. After the reaction is complete, centrifuge at 3500rpm for 5min. Repeat the centrifugation several times until the pH of the centrifuged liquid reaches 6. Freeze-dry it at -70℃ for 48h, grind it into powder, and multilayer Ti3C2 is obtained. Step b: Weigh 0.42g Fe(NO3)3‧9H2O and dissolve it in 50mL of deionized water, then add 10g of nano TiO2 powder, stir at room temperature in the dark for 24h, centrifuge, wash, vacuum dry at 80°C for 2h, grind to obtain Fe / TiO2 catalyst; Step c: Weigh 0.0283g of the prepared Ti3C2 powder and 2.8g of Fe / TiO2 catalyst, add them to 50mL of anhydrous ethanol, and alternate between stirring and sonication for 2h. Transfer the mixture to a 100mL polytetrafluoroethylene-lined reactor and place it in an oven at 180℃ for 24h. After hydrothermal treatment, wash the mixture repeatedly by centrifugation with ethanol and distilled water, then freeze-dry it and grind it thoroughly to obtain the Fe / Ti3C2 / TiO2 catalyst.

[0050] The above embodiments can also be used to prepare Fe / Ti3C2 / TiO2 catalysts under other reaction conditions specified in this invention. As long as the conditions are within the range specified in this invention, the technical effects can be basically equivalent to those described above.

[0051] The TEM image of the nano-TiO2 powder used in this embodiment is as follows. Figure 2 As shown in Figure 3, the TEM image of the prepared Ti3C2 is as follows. Ti3C2 exhibits a layered structure, providing a large specific surface area. The TEM image of the prepared Fe / Ti3C2 / TiO2 catalyst is shown in Figure 3. Figure 4 As shown in the figure, Fe, Ti3C2, and TiO2 have successfully combined.

[0052] Figure 5 The XRD patterns of the Ti3AlC2, Ti3C2, TiO2, and Fe / Ti3C2 / TiO2 catalysts in this embodiment are shown. As can be seen from the figure, the peak intensity near 39° of the multilayer Ti3C2 obtained after etching is significantly reduced compared to before etching, indicating that almost all Al elements were etched away. Furthermore, the peaks near 9.8° and 19.2° have shifted forward and weakened, indicating that the layered structure of the catalyst has changed after etching, and the interlayer spacing has increased. This proves that Ti3AlC2 was successfully etched. Comparing the characteristic peaks of Fe / Ti3C2 / TiO2 and TiO2, the peak positions did not change significantly, but the peak intensity increased. This indicates that the crystal structure of TiO2 did not change significantly, suggesting that the improved activity of the Fe / Ti3C2 / TiO2 catalyst is due to Fe... 3+ Synergistic effect of Ti3C2 and TiO2.

[0053] Figure 6 This is a comparison diagram of the band gap widths of TiO2 and Fe / Ti3C2 / TiO2 in this embodiment. By comparing the band gap widths of TiO2 and Fe / Ti3C2 / TiO2, it can be seen that by doping Fe... 3+ After being combined with Ti3C2, the band gap of TiO2 is greatly shortened, which can effectively accelerate the separation efficiency of electron-hole pairs, enabling the generation of more active oxygen in the same amount of time, so as to better degrade ciprofloxacin wastewater.

[0054] Example 2 This invention provides a method for treating ciprofloxacin wastewater, comprising the following steps: Oxygen was introduced into an ozone generator, and the generated ozone gas and ciprofloxacin simulated wastewater (15L 50mg / L) were simultaneously introduced into a microbubble generator. The ozone flow rate was 0.3L / min, the gas-to-water volume ratio of the microbubble generator was 1:8, and the inlet pressure of the microbubble generator was not less than 0.35MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 254nm, the power was 18W, the current was 0.13A, and the frequency was 55Hz. The Fe / Ti3C2 / TiO2 catalyst prepared in Example 1 was added, and its mass-to-volume ratio with the ciprofloxacin simulated wastewater was 7.5g:15L. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0055] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 99.36%; after 90 minutes of aeration, the TOC removal rate was 69.62% and the ozone utilization rate was 98.14%.

[0056] Example 3 Oxygen was introduced into an ozone generator, and the generated ozone gas and ciprofloxacin simulated wastewater (15L 50mg / L) were simultaneously introduced into a microbubble generator. The ozone flow rate was 0.3L / min, the gas-to-water volume ratio of the microbubble generator was 1:5, and the inlet pressure of the microbubble generator was not less than 0.5MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 256nm, the power was 20W, the current was 0.1A, and the frequency was 50Hz. The Fe / Ti3C2 / TiO2 catalyst prepared in Example 1 was added, and its mass-to-volume ratio with the ciprofloxacin simulated wastewater was 7g:15L. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0057] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 99.23%; after 90 minutes of aeration, the TOC removal rate was 69.56% and the ozone utilization rate was 97.59%.

[0058] Example 4 Oxygen was introduced into an ozone generator, and the generated ozone gas and ciprofloxacin simulated wastewater (15L 50mg / L) were simultaneously introduced into a microbubble generator. The ozone flow rate was 0.3L / min, the gas-to-water volume ratio of the microbubble generator was 1:10, and the pressure before the microbubble generator was not less than 0.25MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 252nm, the power was 15W, the current was 0.15A, and the frequency was 60Hz. The Fe / Ti3C2 / TiO2 catalyst prepared in Example 1 was added, and its mass-to-volume ratio with the ciprofloxacin simulated wastewater was 8g:15L. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0059] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 99.19%; after 90 minutes of aeration, the TOC removal rate was 69.43% and the ozone utilization rate was 97.42%.

[0060] In Examples 2 to 4, the simulated ciprofloxacin wastewater was prepared by dissolving ciprofloxacin in water.

[0061] To better illustrate the technical solution of the present invention, further comparisons are made below using comparative examples and instances of the present invention.

[0062] Comparative Example 1 This comparative example provides a method for treating ciprofloxacin wastewater, which differs from Example 2 only in that it does not include the Fe / Ti3C2 / TiO2 catalyst. The specific steps include: Oxygen was introduced into the ozone generator, and the generated ozone gas and ciprofloxacin simulated wastewater (15L 50mg / L) were simultaneously introduced into the microbubble generator. The ozone flow rate was 0.3L / min, the gas-to-water volume ratio of the microbubble generator was 1:8, and the pressure before the microbubble generator was not less than 0.35MPa. The generated ozone microbubble wastewater was introduced from the bottom into the ultraviolet reactor. The wavelength of the ultraviolet light was 254nm, the power was 18W, the current was 0.13A, and the frequency was 55Hz. Aeration was carried out for 90 minutes, and water samples were taken for testing at regular intervals.

[0063] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 97.63%; after 90 minutes of aeration, the TOC removal rate was 33.23% and the ozone utilization rate was 99.42%.

[0064] Comparative Example 2 This comparative example provides a method for treating ciprofloxacin wastewater, which differs from Example 2 only in that the Fe / Ti3C2 / TiO2 catalyst is replaced with the Fe / TiO2 catalyst prepared in Example 1. The specific steps include: Oxygen was introduced into an ozone generator, and the generated ozone gas and ciprofloxacin simulated wastewater (15L 50mg / L) were simultaneously introduced into a microbubble generator. The ozone flow rate was 0.3L / min, the gas-to-water volume ratio of the microbubble generator was 1:8, and the inlet pressure of the microbubble generator was not less than 0.35MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 254nm, the power was 18W, the current was 0.13A, and the frequency was 55Hz. The Fe / TiO2 catalyst prepared in Example 1 was added, and its mass-to-volume ratio with the ciprofloxacin simulated wastewater was 7.5g:15L. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0065] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 96.84%; after 90 minutes of aeration, the TOC removal rate was 58.27% and the ozone utilization rate was 98.11%.

[0066] Comparative Example 3 This comparative example provides a method for treating ciprofloxacin wastewater, which differs from Example 2 only in that the Fe / Ti3C2 / TiO2 catalyst is replaced with g-C3N4. Specifically, it includes the following steps: Oxygen was introduced into an ozone generator, and the generated ozone gas was simultaneously introduced into a microbubble generator along with 15L of ciprofloxacin-simulated wastewater (50mg / L). The ozone flow rate was 0.3L / min, the gas-to-water volume ratio in the microbubble generator was 1:8, and the inlet pressure of the microbubble generator was not less than 0.35MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 254nm, the power was 18W, the current was 0.13A, and the frequency was 55Hz. g-C3N4 catalyst was added, and its mass-to-volume ratio with the ciprofloxacin-simulated wastewater was 7.5g:15L. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0067] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 97.89%; after 90 minutes of aeration, the TOC removal rate was 29.54% and the ozone utilization rate was 98.53%.

[0068] Comparative Example 4 This comparative example provides a method for treating ciprofloxacin wastewater. The only difference from Example 2 is that the Fe / Ti3C2 / TiO2 catalyst is replaced with Ti3C2 / g-C3N4 / AC; otherwise, it is identical to Example 2. The preparation method of the Ti3C2 / g-C3N4 / AC includes the following steps: Step a: Weigh 6.67g of g-C3N4 and 10g of AC (activated carbon) and add them to 50mL of deionized water. Disperse by sonication for 30min and stir magnetically for 24h. Centrifuge, dry at 80°C overnight, and then transfer to a muffle furnace and calcine at 400°C for 1h to obtain g-C3N4 / AC. Step b: Add 3.2g LiF and 40mL 9M HCl solution to a polytetrafluoroethylene-lined reactor. Place the reactor in a heat-collecting, constant-temperature magnetic stirrer and adjust the water bath temperature to 40℃. React under these conditions for 15min. Weigh 2g Ti3AlC2 and slowly add it to the reactor in small amounts. Adjust the reactor speed to 500rpm and react at 40℃ for 48h. After the reaction is complete, centrifuge at 3500rpm for 5min. Repeat the centrifugation several times until the pH of the centrifuged liquid reaches 6. Freeze-dry it at -70℃ for 48h, grind it into powder, and multilayer Ti3C2 is obtained. Step c: Weigh 0.0283g of Ti3C2 powder and 2.8g of g-C3N4 / AC, add them to 50mL of anhydrous ethanol, stir and sonicate alternately for 2h, transfer to a reaction vessel with a polytetrafluoroethylene liner, place in an oven at 180℃ for 24h, centrifuge, wash, then freeze dry and grind thoroughly to obtain Ti3C2 / g-C3N4 / AC.

[0069] The treatment of ciprofloxacin wastewater using the catalyst prepared above specifically includes the following steps: Oxygen was introduced into an ozone generator, and the generated ozone gas was simultaneously introduced into a microbubble generator along with 15L of ciprofloxacin-simulated wastewater (50mg / L). The ozone flow rate was 0.3L / min, the gas-to-water volume ratio in the microbubble generator was 1:8, and the inlet pressure of the microbubble generator was not less than 0.35MPa. The generated ozone microbubble wastewater was introduced from the bottom into a UV reactor. The UV light wavelength was 254nm, the power was 18W, the current was 0.13A, and the frequency was 55Hz. A Ti3C2 / g-C3N4 / AC catalyst was added, with a mass-to-volume ratio of 7.5g:15L to the ciprofloxacin-simulated wastewater. Aeration was carried out for 90min, and water samples were taken for testing at regular intervals.

[0070] After 15 minutes of aeration, the degradation rate of ciprofloxacin was 96.49%; after 90 minutes of aeration, the TOC removal rate was 50.11% and the ozone utilization rate was 99.85%.

[0071] In summary, the ciprofloxacin wastewater treatment method provided in this embodiment of the invention achieves thorough treatment of recalcitrant ciprofloxacin wastewater through a coupled process design of ozone microbubbles synergistically with Fe / Ti3C2 / TiO2 catalysis and specific wavelength ultraviolet oxidation. There is a synergistic effect between ultraviolet light and ozone; the addition of ultraviolet light generates reactive oxygen species with higher reactivity, which also improves the utilization efficiency of O3 and accelerates the conversion of O3 into free radicals. Adding the Fe / Ti3C2 / TiO2 catalyst to the ultraviolet-coupled ozone microbubble system provides more reactive sites and generates more reactive oxygen species. This invention utilizes the synergistic effect between the Fe / Ti3C2 / TiO2 photocatalyst and the ultraviolet-coupled ozone microbubble system to significantly improve the degradation efficiency, mineralization degree, and ozone utilization rate of ciprofloxacin. Compared with traditional treatment technologies, the treatment technology of this invention greatly improves the treatment level of antibiotic wastewater and has high application value in the field of antibiotic removal from water bodies.

[0072] 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 or improvements 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 for treating antibiotic wastewater, characterized by, The method comprises the following steps: The ozone gas and the antibiotic wastewater to be treated are simultaneously introduced into a micro-bubble generator to obtain ozone micro-bubble wastewater; the ozone micro-bubble wastewater and the Fe / Ti3C2 / TiO2 catalyst are added into an ultraviolet reactor to perform a catalytic oxidation reaction, and treated wastewater is obtained. In the formula, the Fe atom of the Fe / Ti3C2 / TiO2 catalyst is Fe 3+ ; The ultraviolet reactor is internally provided with a plurality of ultraviolet lamps arranged in parallel, and the wavelength of the ultraviolet lamps is 252nm-256nm.

2. The method of treating antibiotic wastewater of claim 1, wherein, The preparation method of the Fe / Ti3C2 / TiO2 catalyst comprises the following steps: The nanometer titanium dioxide and the soluble iron salt are dissolved in deionized water, and light-shield stirring is performed, followed by solid-liquid separation, washing, and drying to obtain the Fe / TiO2 catalyst. The Fe / TiO2 catalyst and Ti3C2 are added into anhydrous ethanol, and uniform mixing is performed, followed by solvent thermal reaction at 150℃-200℃, solid-liquid separation, washing, and drying to obtain the Fe / Ti3C2 / TiO2 catalyst.

3. The method of treating antibiotic wastewater of claim 2, wherein, The mass ratio of the nanometer titanium dioxide to the soluble iron salt is 20:1-25:1; and / or The mass-volume ratio of the soluble iron salt to deionized water is 1g:(110-130)mL; and / or The light-shield stirring is performed for 20h-25h at a temperature of 25℃-30℃.

4. The method of treating antibiotic wastewater of claim 2, wherein, The mass ratio of the Fe / TiO2 catalyst to Ti3C2 is 80:1-120:1; and / or The mass-volume ratio of the Fe / TiO2 catalyst to anhydrous ethanol is 1g:(15-20)mL; and / or The solvent thermal reaction is performed for 24h-36h.

5. The method of treating antibiotic wastewater of claim 2, wherein, The preparation method of the Ti3C2 comprises the following steps: LiF is added into a hydrochloric acid solution, and reaction is performed at 40℃-45℃ for 15min-20min, then Ti3AlC2 is added, and reaction is continuously performed at 40℃-45℃ for 45h-50h, followed by solid-liquid separation, freeze-drying, and grinding to obtain the Ti3C2.

6. The method of treating antibiotic wastewater of claim 5, wherein, The mass-volume ratio of the LiF to the hydrochloric acid solution is (1.5-2)g:20mL, and the concentration of the hydrochloric acid solution is 8mol / L-10mol / L; and / or The mass ratio of the LiF to Ti3AlC2 is 1.5:1-2:

1.

7. The method of treating antibiotic wastewater of claim 1, wherein, The gas-water volume ratio of the micro-bubble generator is 1:5-1:10, and the pipe front pressure of the micro-bubble generator is 0.25MPa-0.5MPa; and / or The power of the ultraviolet lamp is 15W-20W, the current is 0.1A-0.15A, and the frequency is 50Hz-60Hz; and / or The catalytic oxidation reaction is performed for 60min-90min.

8. The method of treating antibiotic wastewater of claim 1, wherein, The mass-volume ratio of the Fe / Ti3C2 / TiO2 catalyst to the antibiotic wastewater to be treated is (7-8)g:15L.

9. The apparatus for the treatment of antibiotic waste water as claimed in any one of claims 1 to 8, characterized in that, The system comprises an ozone generator, a micro-bubble generator, and an ultraviolet reactor connected in sequence; the water inlet of the micro-bubble generator is connected to the upper portion of the ultraviolet reactor, and the water outlet is connected to the bottom of the ultraviolet reactor.

10. The apparatus for treatment of antibiotic wastewater as claimed in claim 9, wherein, The ultraviolet reactor comprises a reactor body and a plurality of ultraviolet lamps arranged in parallel inside the reactor body; the ultraviolet lamps are immersed in the antibiotic wastewater to be treated in the reactor body.

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