Supported ozone catalyst for printing and dyeing wastewater treatment and treatment process

Abstract

The invention discloses a supported ozone catalyst for printing and dyeing wastewater treatment and a treatment process, and relates to the technical field of wastewater treatment, the supported ozone catalyst comprises an environmental response type porous medium, an active center and a biological enzyme modification layer; the environment-responsive porous medium is based on poly (N-isopropylacrylamide) grafted and modified mesoporous alumina, the initial aperture of the mesoporous alumina is 10-15nm, the grafting rate of poly (N-isopropylacrylamide) is 12-20%, and an active center is composed of a transition metal active center and quantum dots modified on the transition metal active center. The biological enzyme modified layer is obtained by carrying out deep biological modification on the surface of the catalyst by using laccase with oxidation-reduction activity. According to the invention, an environment-responsive porous medium is constructed by grafting mesoporous alumina with poly (N-isopropylacrylamide), so that the problems that a traditional fixed-aperture catalyst is low in mass transfer efficiency and poor in adaptability to working conditions, and the pollutant release efficiency is difficult to effectively improve under different temperature and pH conditions are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and specifically to a supported ozone catalyst for printing and dyeing wastewater treatment and a treatment process. Background Art

[0002] Traditional ozone catalysts cannot achieve dynamic adjustment of pore size according to environmental conditions, and cannot change their own pore size according to different temperature and pH environments to adapt to mass transfer requirements, resulting in low mass transfer efficiency in practical applications and poor adaptability to complex working conditions. It is difficult to effectively improve the pollutant release efficiency under different temperature and pH conditions, which limits their treatment effect on pollutants. The ozone catalyst of the present application can solve the problems of low mass transfer efficiency of traditional fixed-pore-size catalysts, poor adaptability to working conditions, and difficulty in effectively improving pollutant release efficiency under different temperature and pH conditions.

[0003] The defects of existing ozone catalysts are as follows: 1. Patent document CN105080565B discloses a preparation method of a supported ozone oxidation catalyst. This document mainly considers how to provide a preparation method of a supported ozone oxidation catalyst with simple preparation process, reduced catalytic oxidation cost, good catalytic activity, and strong anti-poisoning ability, without considering how to solve the problems of low mass transfer efficiency of traditional fixed-pore-size catalysts, poor adaptability to working conditions, and difficulty in effectively improving pollutant release efficiency under different temperature and pH conditions; 2. Patent document CN117960173B discloses a preparation method of a supported-blended ozone catalyst. This document mainly considers how to solve the problems in the prior art, such as low catalytic performance of ozone catalysts, high cost of preparation raw materials, and reduction of aggregate activity and specific surface area due to high-temperature roasting during the preparation process, without considering how to solve the problems that traditional ozone catalysts rely on ultraviolet light or high-temperature conditions, low photocatalytic efficiency, high reaction activation energy, and difficulty in efficiently activating ozone decomposition at room temperature; 3. Patent document CN103240115B discloses a supported ozone catalytic oxidation catalyst and its preparation method. This document mainly considers how to find a suitable carrier molecular sieve and a loading method of metal oxides to prepare a new supported ozone catalytic oxidation catalyst to improve the treatment effect of organic wastewater, without considering how to solve the problems that existing biofilms are easily inactivated, need off-line regeneration, have a long regeneration period and high operation cost, and are difficult to effectively inhibit side reactions, unstable cationic dye adsorption capacity, and short continuous operation life of the catalyst; 4. Patent document CN101664681B discloses a supported catalyst for multiphase catalytic ozonation and its preparation method. This document mainly considers the problems that the catalyst is difficult to recycle, the reagent cost is high, impurities are introduced to cause secondary pollution, the ozone utilization rate is low, and the treatment efficiency is poor during the use of the catalyst. It does not consider how to solve the problems of low COD removal rate, low decolorization rate, low treatment efficiency, high energy consumption, difficult high-efficiency recovery of the catalyst, and deficiencies in treating macromolecular pollutants when using traditional single processes to treat sewage. Summary of the Invention

[0004] The purpose of the present invention is to provide a supported ozone catalyst and a treatment process for printing and dyeing wastewater to solve the problems raised in the above background technology.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A supported ozone catalyst for printing and dyeing wastewater treatment, the supported ozone catalyst includes an environmentally responsive porous medium, an active center, and a bio-enzyme modified layer; The environmentally responsive porous medium is based on mesoporous alumina grafted with poly(N-isopropylacrylamide). The initial pore diameter of the mesoporous alumina is 10 - 15 nm, the grafting rate of poly(N-isopropylacrylamide) is 12 - 20%, and it has temperature-responsive characteristics in the range of 25 - 40 °C; The active center is composed of a transition metal active center and quantum dots modified thereon; The bio-enzyme modified layer is obtained by deeply bio-modifying the surface of the catalyst with laccase having redox activity.

[0006] Preferably, a preparation method of a supported ozone catalyst for printing and dyeing wastewater treatment, the preparation method of the supported ozone catalyst is as follows: S1. Prepare a mesoporous alumina support by the template method, and then use surface-initiated atom transfer radical polymerization technology to graft poly(N-isopropylacrylamide) onto the mesoporous alumina to obtain an environmentally responsive porous medium; S2. Configure a precursor solution of the transition metal active center, immerse the environmentally responsive porous medium therein to load the active center onto the medium, and then prepare a cadmium sulfide quantum dot solution by hydrothermal synthesis method. Immerse the environmentally responsive porous medium in the quantum dot solution to obtain a supported medium with quantum dots modifying the active center; S3. Bio-enzyme assisted surface modification to obtain the supported ozone catalyst.

[0007] Preferably, in S1, the following is further included: S11. The template agent adopts a composite system of block copolymer F127 and cetyltrimethylammonium bromide, and the mass ratio is 3:1; Aluminum nitrate nonahydrate and the template agent were ultrasonically dispersed in a mixed solvent of ethanol and water in a volume ratio of 7:3 for 30 minutes, and hydrothermally reacted at 80° C. for 24 hours. Before calcination, 0.1 M dilute hydrochloric acid was used for gradient elution to remove the template agent. S12, the initiator is 2-bromoisobutyryl bromide, which is bonded to the surface of alumina through a silane coupling agent KH570, and the grafting density is 0.8-1.2 mmol / g; The polymerization conditions are as follows: the concentration of the monomer N-isopropylacrylamide is 0.5 M, the molar ratio of the catalyst cuprous bromide / ligand pentamethyldiethylenetriamine is 1:2, and the reaction is carried out at 60° C. for 6 hours under nitrogen protection.

[0008] Preferably, in S2, the following is also included: S21, respectively preparing solutions containing manganese, iron, and copper precursors, and mixing them evenly in a molar ratio of manganese: iron: copper = 2:1:1 to obtain a transition metal active center precursor solution; S22, immersing the environmentally responsive porous medium in a transition metal active center precursor solution, fully adsorbing under ultrasonic-assisted conditions, with the ultrasonic frequency set to 40 kHz, the ultrasonic power to 200 W, and the ultrasonic time to 30 minutes, followed by drying in a vacuum environment at 120°C for 12 hours, and then calcining in a muffle furnace at 500°C for 4 hours, so that the transition metal active center is firmly loaded on the medium; S23. A cadmium sulfide quantum dot solution with a particle size of 3 to 4 nm is prepared by a hydrothermal synthesis method. The medium loaded with transition metal active centers is immersed in the quantum dot solution. The solution is fully reacted under magnetic stirring to control the quantum dot loading amount to 3.5 to 4.5% of the total mass of the catalyst. The solution is then dried in an oven at 60°C for 8 hours to obtain a loaded medium with quantum dot-modified active centers.

[0009] Preferably, S3 further includes the following: S31, preparing a laccase solution with a concentration of 0.5-1.0 mg / mL, placing the loaded medium in the laccase solution, and treating in a shaker at a temperature of 32-34° C. and a rotation speed of 100-150 r / min for 2.5-3.5 hours; S32. After the treatment is completed, the medium is washed with deionized water for multiple times to remove unreacted laccase, and then dried in a vacuum drying oven at 40° C. for 10 hours to obtain the final supported ozone catalyst.

[0010] Preferably, a treatment process of a supported ozone catalyst for treating printing and dyeing wastewater comprises the following: S1. Use ultrasonic and electrochemical technology to pre-treat printing and dyeing wastewater; S2. Catalytic oxidation treatment of printing and dyeing wastewater is achieved by using ozone and microwave through a fluidized bed reactor; S3. Adjust the pore size of the medium and the catalytic reaction according to the condition changes in the printing and dyeing wastewater treatment stage; S4. In-situ regeneration of the catalyst biofilm and performance stability control are achieved through bioenzymes; S5. Solid-liquid separation and resource recovery of the treated printing and dyeing wastewater are carried out by using magnetic separation and membrane treatment technologies.

[0011] Preferably, in S1, the following are further included: S11. Treat with 20 kHz high-frequency ultrasound for 10 minutes, with a sound energy density of 0.8 W / cm³, to break the macromolecular pollutant chains; S12. Inject CO2 microbubbles with a diameter less than 50 μm to adjust the pH of the wastewater to 6.5 ± 0.2, providing a neutral environment for the subsequent response of the responsive porous medium; In S2, the following are further included: S21. Inject ozone at an initial concentration of 120 mg / L, and reduce it to 80 mg / L after 15 minutes. Combine with microwave dynamic adjustment to make the surface active centers of the catalyst alternately in the states of high-concentration ozone adsorption and free radical generation; S22. Adopt a 2450 MHz microwave pulse mode, with a duty cycle of 2:1 and an average power of 250 W. At 35 - 40 °C, stimulate the poly N-isopropylacrylamide chain segments of the responsive porous medium to stretch to a pore size of 18 - 20 nm, and at the same time activate the photo-generated electron-hole pairs of the quantum dots.

[0012] Preferably, in S3, the following are further included: S31. In the low-temperature acidic stage at 15 - 20 °C and pH 4 - 5, the poly N-isopropylacrylamide chain segments contract to a pore size of 6 - 8 nm, adsorbing and enriching small-molecule printing and dyeing pollutants; In the high-temperature alkaline stage at 35 - 40 °C and pH 8 - 9, the poly N-isopropylacrylamide chain segments stretch, the pore size of the medium increases to 18 - 20 nm, and the adsorbed pollutants are released to the surface of the active centers, promoting a 40% increase in the mass transfer efficiency; S32. Under microwave excitation, the cadmium sulfide quantum dots of 3 - 4 nm generate photo-generated electron-hole pairs, and the absorption of visible light with a wavelength of 520 nm is enhanced through the surface plasmon resonance effect, making the hydroxyl radical yield reach 1.2 × 10¹⁸ radicals / mL·min.

[0013] Preferably, in S4, the following are further included: S41. After every 2 hours of treatment, inject 0.1% ABTS solution as a laccase mediator, maintain it at 32 °C for 30 minutes, and restore the adsorption capacity of the biofilm for cationic dyes through an enzymatic cross-linking reaction, exceeding 180 mg / g. S42. Real-time monitor the biofilm protein concentration through UV-Vis spectroscopy at a wavelength of 280 nm, automatically adjust the dosage of the activator to ensure that the biofilm thickness is stable at 50 - 80 nm, and inhibit the occurrence of side reactions.

[0014] Preferably, in S5, the following is also included: S51. The effluent is treated by a ceramic membrane with a pore size of 50 nm and nanofiltration. The produced water has a COD of less than 50 mg / L, a conductivity of less than 200 μS / cm, and a recycling rate of up to 85%. S52. The concentrated solution is subjected to evaporation crystallization to recover inorganic salts, and the residue is purified for precious metals through an acid dissolution - extraction process, with a recovery rate exceeding 98%.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention constructs an environmentally responsive porous medium by grafting poly(N-isopropylacrylamide) onto mesoporous alumina, realizing dynamic adjustment of the pore size in the range of 6 - 20 nm with temperature from 10 - 48 °C and pH from 4 - 9. Compared with traditional catalysts with fixed pore sizes, this design increases the mass transfer efficiency by 40%. Experimental data show that under alkaline conditions at 35 - 40 °C, the pore size of the medium expands to 18 - 20 nm, and the pollutant release efficiency is significantly improved, breaking through the technical bottleneck of poor adaptability of traditional catalysts to working conditions. Therefore, it can solve the problems of low mass transfer efficiency of traditional fixed-pore catalysts and poor adaptability to working conditions, and it is difficult to effectively improve the pollutant release efficiency under different temperature and pH conditions.

[0016] 2. The present invention uses surface plasmon resonance of cadmium sulfide quantum dots to modify transition metal active centers. Under the excitation of 2450 MHz microwaves, it realizes enhanced visible light absorption at 520 nm and a hydroxyl radical yield of 1.32 - 1.58×10¹⁸ radicals / mL·min. Compared with traditional ozone catalysts that rely on ultraviolet light or high-temperature conditions, this technology improves the photocatalytic efficiency by 86 - 88%, and at the same time reduces the reaction activation energy to below 35 °C. Experimental verification shows that quantum dot modification enables the catalyst to efficiently activate ozone decomposition at room temperature. Therefore, it can solve the problems of traditional ozone catalysts relying on ultraviolet light or high-temperature conditions, low photocatalytic efficiency, and high reaction activation energy, and it is difficult to efficiently activate ozone decomposition at room temperature.

[0017] 3. The present invention realizes the dynamic repair of the biofilm through the laccase-ABTS mediator system, enabling the cationic dye adsorption capacity to be stably maintained above 180 mg / g, and extending the continuous operation life of the catalyst to 380 - 450 hours. Compared with the existing technologies where the biofilm is prone to inactivation and requires off-line regeneration, this method dynamically adjusts the dosage of the activator by real-time monitoring the biofilm protein concentration, shortening the regeneration cycle to 2 hours per time and significantly reducing the operating cost. Experiments show that the thickness of the regenerated biofilm is stably controlled within 50 - 80 nm, effectively inhibiting the occurrence of side reactions. Therefore, it can solve the problems of the existing biofilm being prone to inactivation, requiring off-line regeneration, having a long regeneration cycle and high operating cost, and being difficult to effectively inhibit the occurrence of side reactions, unstable cationic dye adsorption capacity, and short continuous operation life of the catalyst.

[0018] 4. The present invention integrates ultrasonic fragmentation, microwave intensification, ozone catalysis, and magnetic membrane separation technologies. Under the conditions of influent COD = 1000 mg / L and chromaticity of 6000 times, it achieves a COD removal rate of 95.2% and a decolorization rate of 99.5%, with an energy consumption of only 0.92 kWh / m3. Compared with traditional single processes, this system pre-fragments macromolecular pollutants by ultrasound, generates hydroxyl radicals through microwave synergistic ozone, and efficiently recovers the catalyst by magnetic membrane, increasing the treatment efficiency by 30% and reducing the energy consumption by 41%. Experiments of the blank control group confirm that omitting quantum dots and microwave treatment will lead to a 17 - 21% decrease in the pollutant removal rate, verifying the necessity of multi-field coupling. Therefore, it can solve the problems of low COD removal rate and decolorization rate, low treatment efficiency, high energy consumption, difficulty in efficiently recovering the catalyst, and deficiencies in treating macromolecular pollutants when using traditional single processes to treat sewage. Detailed implementation manners

[0019] The technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Embodiment

[0020] A supported ozone catalyst for printing and dyeing wastewater treatment, which includes an environment-responsive porous medium, an active center, and a bioenzyme modification layer; The environment-responsive porous medium is based on mesoporous alumina grafted with poly(N-isopropylacrylamide). The initial pore diameter of the mesoporous alumina is 10 - 15 nm, the grafting rate of poly(N-isopropylacrylamide) is 12 - 20%, and it has temperature-responsive characteristics within the range of 25 - 40 °C; The active center is composed of a transition metal active center and quantum dots modified thereon; The bio-enzyme modified layer is obtained by deeply bio-modifying the surface of the catalyst with laccase having redox activity. Example

[0021] A preparation method of a supported ozone catalyst for printing and dyeing wastewater treatment, the preparation method of the supported ozone catalyst is as follows: S1. Prepare a mesoporous alumina support by the template method, and then graft poly(N-isopropylacrylamide) onto the mesoporous alumina by surface-initiated atom transfer radical polymerization technology to obtain an environmentally responsive porous medium; S2. Configure a precursor solution of a transition metal active center, immerse the environmentally responsive porous medium therein to load the active center onto the medium, then prepare a cadmium sulfide quantum dot solution by hydrothermal synthesis method, and immerse the environmentally responsive porous medium in the quantum dot solution to obtain a supported medium with quantum dots modifying the active center; S3. Bio-enzyme assisted surface modification to obtain the supported ozone catalyst.

[0022] , in S1, the following is also included: S11. The template agent adopts a composite system of block copolymer F127 and cetyltrimethylammonium bromide, and the mass ratio is 3:1; Ultrasonically disperse aluminum nitrate nonahydrate and the template agent in a mixed solvent of ethanol and water for 30 minutes, the volume ratio of ethanol and water in the mixture is 7:3, carry out hydrothermal reaction at 80 °C for 24 hours, and use 0.1M dilute hydrochloric acid for gradient elution to remove the template agent before calcination; S12. The initiator adopts 2-bromoisobutyryl bromide, which is bonded to the alumina surface through the silane coupling agent KH570, and the grafting density is 1.0 mmol / g; The polymerization conditions are that the concentration of monomer N-isopropylacrylamide is 0.5M, the molar ratio of catalyst cuprous bromide / ligand pentamethyldiethylenetriamine is 1:2, and the reaction is carried out at 60 °C for 6 hours under nitrogen protection.

[0023] , in S2, the following is also included: S21. Respectively configure solutions containing manganese, iron, and copper precursors, mix them evenly according to the molar ratio of manganese:iron:copper = 2:1:1 to obtain a precursor solution of a transition metal active center; Immerse the environmentally responsive porous medium in the precursor solution of the transition metal active center, fully adsorb it under ultrasonic assistance, set the ultrasonic frequency to 40 kHz, the ultrasonic power to 200 W, and the ultrasonic time to 30 minutes, then dry it in a vacuum environment at 120 °C for 12 hours, and then calcine it in a muffle furnace at 500 °C for 4 hours to firmly load the transition metal active center onto the medium; S23. Prepare cadmium sulfide quantum dot solution with a particle size of 3 nm by hydrothermal synthesis method. Immerse the medium loaded with transition metal active centers in the quantum dot solution, and react fully under magnetic stirring. Control the quantum dot loading amount to account for 3.8% of the total mass of the catalyst. Then dry it in an oven at 60 °C for 8 hours to obtain a supported medium with quantum dots modifying the active centers.

[0024] In S3, it also includes the following: S31. Prepare laccase solution with a concentration of 0.5 mg / mL. Place the supported medium in the laccase solution and treat it in a shaker at a temperature of 32 °C and a rotation speed of 100 r / min for 3.5 hours. S32. After the treatment, wash the medium with deionized water multiple times to remove the unreacted laccase, and then dry it in a vacuum drying oven at 40 °C for 10 hours to obtain the final supported ozone catalyst.

[0025] A treatment process for a supported ozone catalyst used in printing and dyeing wastewater treatment. The treatment process of the supported ozone catalyst includes the following: S1. Use ultrasonic and electrochemical technologies to pre-treat the printing and dyeing wastewater. S2. Through a fluidized bed reactor, use ozone and microwave to achieve catalytic oxidation treatment of the printing and dyeing wastewater. S3. Adjust the medium pore size and catalytic reaction according to the condition changes in the printing and dyeing wastewater treatment stage. S4. Achieve in-situ regeneration of the catalyst biofilm and performance stability control through bioenzymes. S5. Use magnetic separation and membrane treatment technologies to perform solid-liquid separation and resource recovery on the treated printing and dyeing wastewater.

[0026] In S1, it also includes the following: S11. Use 20 kHz high-frequency ultrasound to treat for 10 minutes with an acoustic energy density of 0.8 W / cm³ to break the macromolecular pollutant chains. S12. Introduce CO2 microbubbles with a diameter less than 50 μm to adjust the pH of the wastewater to 6.5 ± 0.2 to provide a neutral environment for the subsequent response of the responsive porous medium. In S2, it also includes the following: S21. Initially introduce ozone at a concentration of 120 mg / L. After 15 minutes, reduce it to 80 mg / L, and combine with microwave dynamic adjustment to make the active centers on the catalyst surface alternately in the states of high-concentration ozone adsorption and free radical generation. S22. Adopt a 2450 MHz microwave pulse mode with a duty cycle of 2:1 and an average power of 250 W. At 35 °C, stimulate the responsive porous medium to stretch the poly-N-isopropylacrylamide chain segments to a pore size of 18 - 20 nm, and at the same time activate the photo-generated electron-hole pairs of the quantum dots.

[0027] In S3, the following are also included: S31. In the low-temperature acidic stage at 15 - 20 °C and pH 4 - 5, the poly-N-isopropylacrylamide chain segments contract to a pore size of 6 - 8 nm, adsorbing and enriching small-molecule dye pollutants; In the high-temperature alkaline stage at 35 - 40 °C and pH 8 - 9, the poly-N-isopropylacrylamide chain segments stretch, the pore size of the medium increases to 18 - 20 nm, releasing the adsorbed pollutants to the surface of the active center and promoting a 40% increase in the mass transfer efficiency; S32. Under microwave excitation, cadmium sulfide quantum dots of 3 - 4 nm generate photoinduced electron-hole pairs, enhancing the absorption of visible light with a wavelength of 520 nm through the surface plasmon resonance effect, and achieving a hydroxyl radical yield of 1.2×10¹⁸ radicals / mL·min.

[0028] In S4, the following are also included: S41. After every 2 hours of treatment, 0.1% ABTS solution is injected as a laccase mediator and maintained at 32 °C for 30 minutes. Through the enzymatic cross-linking reaction, the adsorption capacity of the biofilm for cationic dyes is restored, exceeding 180 mg / g; S42. The protein concentration of the biofilm is monitored in real-time by UV-Vis spectroscopy at a wavelength of 280 nm, and the dosage of the activator is automatically adjusted to ensure that the biofilm thickness is stable at 50 - 80 nm, inhibiting the occurrence of side reactions.

[0029] In S5, the following are also included: S51. The effluent is treated by a ceramic membrane with a pore size of 50 nm and nanofiltration; S52. The concentrated solution is subjected to evaporation crystallization to recover inorganic salts, and the residue is purified for precious metals through an acid dissolution-extraction process. Example

[0030] A preparation method of a supported ozone catalyst for dyeing wastewater treatment, and the preparation method of the supported ozone catalyst is as follows: S1. The mesoporous alumina support is prepared by the template method, and then poly-N-isopropylacrylamide is grafted onto the mesoporous alumina by surface-initiated atom transfer radical polymerization technology to obtain an environmentally responsive porous medium; S2. A precursor solution of the transition metal active center is prepared, and the environmentally responsive porous medium is impregnated therein to load the active center onto the medium. Then, a cadmium sulfide quantum dot solution is prepared by the hydrothermal synthesis method, and the environmentally responsive porous medium is impregnated in the quantum dot solution to obtain a supported medium with quantum dots modifying the active center; S3. Bioenzyme-assisted surface modification is carried out to obtain the supported ozone catalyst.

[0031] In S1, the following are also included: S11. The template agent uses a compound system of block copolymer F127 and cetyltrimethylammonium bromide, and the mass ratio is 2:1; Ultrasonically disperse aluminum nitrate nonahydrate and the template agent in a mixed solvent of ethanol and water for 30 minutes. The mixed volume ratio of ethanol and water is 7:3. Carry out hydrothermal reaction at 80 °C for 24 hours. Before calcination, use 0.1M dilute hydrochloric acid for gradient elution to remove the template agent; S12. The initiator uses 2-bromoisobutyryl bromide, which is bonded to the alumina surface through the silane coupling agent KH570, and the grafting density is 1.2 mmol / g; The polymerization conditions are that the concentration of monomer N-isopropylacrylamide is 0.5M, and the molar ratio of catalyst cuprous bromide / ligand pentamethyldiethylenetriamine is 1:2. React at 65 °C for 6 hours under nitrogen protection.

[0032] In S2, the following are also included: S21. Prepare solutions containing manganese, iron, and copper precursors respectively, and mix them evenly according to the molar ratio of manganese:iron:copper = 2:1:1 to obtain a transition metal active center precursor solution; S22. Immerse the environmentally responsive porous medium in the transition metal active center precursor solution, and fully adsorb it under ultrasonic assistance. The ultrasonic frequency is set to 40 kHz, the ultrasonic power is 200 W, and the ultrasonic time is 30 minutes. Then dry it in a vacuum environment at 120 °C for 12 hours, and then calcine it in a muffle furnace at 500 °C for 4 hours to firmly load the transition metal active center onto the medium; S23. Prepare a cadmium sulfide quantum dot solution with a particle size of 3 nm by hydrothermal synthesis method. Immerse the medium loaded with the transition metal active center in the quantum dot solution, and fully react under magnetic stirring. Control the quantum dot loading amount to account for 4.3% of the total mass of the catalyst. Then dry it in an oven at 60 °C for 8 hours to obtain a supported medium with quantum dots modified on the active center.

[0033] In S3, the following are also included: S31. Prepare a laccase solution with a concentration of 0.9 mg / mL. Place the supported medium in the laccase solution and treat it in a shaker at a temperature of 33 °C and a rotation speed of 100 r / min for 3.5 hours; S32. After the treatment is completed, wash the medium with deionized water multiple times to remove the unreacted laccase, and then dry it in a vacuum drying oven at 40 °C for 10 hours to obtain the final supported ozone catalyst.

[0034] A treatment process for a supported ozone catalyst used for printing and dyeing wastewater treatment. The treatment process of the supported ozone catalyst includes the following: S1. Use ultrasonic and electrochemical technologies to pre-treat the printing and dyeing wastewater; S2. Catalytic oxidation treatment of printing and dyeing wastewater is achieved by using ozone and microwave through a fluidized bed reactor; S3. Adjust the pore size of the medium and the catalytic reaction according to the condition changes in the printing and dyeing wastewater treatment stage; S4. In-situ regeneration of the catalyst biofilm and performance stability control are achieved through bioenzymes; S5. Solid-liquid separation and resource recovery of the treated printing and dyeing wastewater are carried out by using magnetic separation and membrane treatment technologies.

[0035] In S1, the following are also included: S11. Treat with 20 kHz high-frequency ultrasound for 8 minutes, with an acoustic energy density of 1.0 W / cm³, to break the macromolecular pollutant chains; S12. Inject CO2 microbubbles with a diameter less than 50 μm to adjust the pH of the wastewater to 6.5 ± 0.2, providing a neutral environment for the subsequent response of the responsive porous medium; In S2, the following are also included: S21. Initially, ozone is introduced at a concentration of 120 mg / L. After 15 minutes, it is reduced to 80 mg / L. Combined with dynamic microwave adjustment, the active centers on the catalyst surface are alternately in a state of high-concentration ozone adsorption and free radical generation; S22. Adopt a 2450 MHz microwave pulse mode, with a duty cycle of 2:1 and an average power of 250 W. At 35 °C, stimulate the poly N-isopropylacrylamide chain segments of the responsive porous medium to stretch to a pore size of 18 - 20 nm, and at the same time activate the photo-generated electron-hole pairs of quantum dots.

[0036] In S3, the following are also included: S31. In the low-temperature acidic stage at 15 - 20 °C and pH 4 - 5, the poly N-isopropylacrylamide chain segments contract to a pore size of 6 - 8 nm, adsorbing and enriching small-molecule printing and dyeing pollutants; In the high-temperature alkaline stage at 35 - 40 °C and pH 8 - 9, the poly N-isopropylacrylamide chain segments stretch, the pore size of the medium increases to 18 - 20 nm, and the adsorbed pollutants are released to the surface of the active centers, promoting a 40% increase in the mass transfer efficiency; S32. Under microwave excitation, cadmium sulfide quantum dots with a size of 3 - 4 nm generate photo-generated electron-hole pairs, enhancing the absorption of visible light with a wavelength of 520 nm through the surface plasmon resonance effect, and achieving a hydroxyl radical yield of 1.2×1018 radicals / mL・min.

[0037] In S4, the following are also included: S41. After every 2 hours of treatment, inject a 0.11% ABTS solution as a laccase mediator and maintain it at 32 °C for 25 minutes. Through the enzyme-catalyzed cross-linking reaction, the adsorption capacity of the biofilm for cationic dyes is restored to more than 180 mg / g; S42. Monitor the concentration of biofilm proteins in real time through UV-Vis spectroscopy at a wavelength of 280 nm, automatically adjust the dosage of the activator to ensure that the biofilm thickness is stable at 50 - 80 nm, and inhibit the occurrence of side reactions.

[0038] In S5, the following is also included: S51. The effluent is treated by a ceramic membrane with a pore size of 50 nm and nanofiltration. S52. The concentrated liquid is subjected to evaporation crystallization to recover inorganic salts, and the residue is purified for precious metals through an acid dissolution - extraction process. Example

[0039] A preparation method of a supported ozone catalyst for printing and dyeing wastewater treatment, and the preparation method of the supported ozone catalyst is as follows: S1. Prepare a mesoporous alumina support by the template method, and then use surface - initiated atom transfer radical polymerization technology to graft poly(N - isopropylacrylamide) onto the mesoporous alumina to obtain an environmentally responsive porous medium. S2. Configure a precursor solution of transition metal active centers, immerse the environmentally responsive porous medium therein to load the active centers onto the medium, then prepare a cadmium sulfide quantum dot solution by hydrothermal synthesis method, and immerse the environmentally responsive porous medium in the quantum dot solution to obtain a supported medium with quantum dots modifying the active centers. S3. Conduct bio - enzyme - assisted surface modification to obtain a supported ozone catalyst.

[0040] , in S1, the following is also included: S11. The template agent adopts a composite system of block copolymer F127 and cetyltrimethylammonium bromide with a mass ratio of 3:1. Ultrasonically disperse aluminum nitrate nonahydrate and the template agent in a mixed solvent of ethanol and water for 30 minutes. The volume ratio of ethanol to water in the mixed solvent is 7:3. Conduct hydrothermal reaction at 80 °C for 24 hours, and use 0.1 M dilute hydrochloric acid for gradient elution to remove the template agent before calcination. S12. The initiator adopts 2 - bromoisobutyryl bromide, which is bonded to the alumina surface through a silane coupling agent KH570, and the grafting density is 0.8 mmol / g. The polymerization conditions are that the concentration of monomer N - isopropylacrylamide is 0.5 M, the molar ratio of catalyst copper(I) bromide / ligand pentamethyldiethylenetriamine is 1:2, and the reaction is carried out at 60 °C for 6 hours under nitrogen protection.

[0041] In S2, the following is also included: S21. Respectively configure solutions containing manganese, iron, and copper precursors, mix them evenly according to the molar ratio of manganese:iron:copper = 2:1:1 to obtain a precursor solution of transition metal active centers. S22. Immerse the environment-responsive porous medium in the precursor solution of transition metal active centers, and fully adsorb it under ultrasonic assistance. The ultrasonic frequency is set at 40 kHz, the ultrasonic power is 200 W, and the ultrasonic time is 30 minutes. Subsequently, dry it in a vacuum environment at 120 °C for 12 hours, and then calcine it in a muffle furnace at 500 °C for 4 hours to firmly load the transition metal active centers onto the medium; S23. Prepare a cadmium sulfide quantum dot solution with a particle size of 4 nm by hydrothermal synthesis method. Immerse the medium loaded with transition metal active centers in the quantum dot solution, and fully react it under magnetic stirring. Control the quantum dot loading amount to account for 3.6% of the total mass of the catalyst. Then dry it in an oven at 60 °C for 8 hours to obtain a supported medium with quantum dots modifying the active centers.

[0042] In S3, the following is also included: S31. Prepare a laccase solution with a concentration of 0.5 mg / mL. Place the supported medium in the laccase solution and treat it in a shaker at a temperature of 32 °C and a rotation speed of 100 r / min for 3.5 hours; S32. After the treatment, wash the medium with deionized water multiple times to remove the unreacted laccase, and then dry it in a vacuum drying oven at 40 °C for 10 hours to obtain the final supported ozone catalyst.

[0043] A treatment process for a supported ozone catalyst used in printing and dyeing wastewater treatment. The treatment process of the supported ozone catalyst includes the following: S1. Use ultrasonic and electrochemical technologies to pre-treat the printing and dyeing wastewater; S2. Through a fluidized bed reactor, use ozone and microwave to achieve catalytic oxidation treatment of the printing and dyeing wastewater; S3. Adjust the pore size of the medium and the catalytic reaction according to the condition changes in the printing and dyeing wastewater treatment stage; S4. Achieve in-situ regeneration of the catalyst biofilm and performance stability control through bioenzymes; S5. Use magnetic separation and membrane treatment technologies to carry out solid-liquid separation and resource recovery of the treated printing and dyeing wastewater.

[0044] In S1, the following is also included: S11. Use 20 kHz high-frequency ultrasonic treatment for 10 minutes with an acoustic energy density of 0.8 W / cm³ to break the macromolecular pollutant chains; S12. Introduce CO2 microbubbles with a diameter less than 30 μm to adjust the pH of the wastewater to 6.5 ± 0.2 to provide a neutral environment for the subsequent response of the responsive porous medium; In S2, the following is also included: S21. At the initial stage, ozone is introduced at a concentration of 120 mg / L. After 15 minutes, it is reduced to 80 mg / L. Combined with dynamic microwave adjustment, the active centers on the catalyst surface are alternately in the states of high-concentration ozone adsorption and free radical generation; S22. Adopt a 2450 MHz microwave pulse mode with a duty cycle of 2:1 and an average power of 250 W. At 35 °C, the responsive porous medium poly(N-isopropylacrylamide) chain segments are excited to stretch to a pore size of 18 - 20 nm, and at the same time, the photo-generated electron-hole pairs of quantum dots are activated.

[0045] In S3, the following are also included: S31. In the low-temperature acidic stage at 15 - 20 °C and pH 4 - 5, the poly(N-isopropylacrylamide) chain segments contract to a pore size of 6 - 8 nm, adsorbing and enriching small molecule dye pollutants; In the high-temperature alkaline stage at 35 - 40 °C and pH 8 - 9, the poly(N-isopropylacrylamide) chain segments stretch, the pore size of the medium increases to 18 - 20 nm, and the adsorbed pollutants are released to the surface of the active center, promoting a 40% increase in the mass transfer efficiency; S32. Under microwave excitation, cadmium sulfide quantum dots with a size of 3 - 4 nm generate photo-generated electron-hole pairs, enhancing the absorption of visible light with a wavelength of 520 nm through the surface plasmon resonance effect, and enabling the hydroxyl radical yield to reach 1.2×10¹⁸ radicals / mL·min.

[0046] In S4, the following are also included: S41. After every 2 hours of treatment, a 0.1% ABTS solution is injected as a laccase mediator and maintained at 32 °C for 30 minutes. Through the enzyme-catalyzed cross-linking reaction, the adsorption capacity of the biofilm for cationic dyes is restored to more than 180 mg / g; S42. The protein concentration of the biofilm is monitored in real time by UV-Vis spectroscopy at a wavelength of 280 nm, and the dosage of the activator is automatically adjusted to ensure that the biofilm thickness is stable at 50 - 80 nm, inhibiting the occurrence of side reactions.

[0047] In S5, the following are also included: S51. The effluent is treated by a ceramic membrane with a pore size of 50 nm and nanofiltration; S52. The concentrated solution is evaporated and crystallized to recover inorganic salts, and the residue is purified for precious metals through an acid dissolution-extraction process. Example

[0048] A blank control group is set. In the preparation method of the supported ozone catalyst, S23 is omitted, the grafting density is 0.9 mmol / g, and the laccase concentration is 0.6 mg / mL. The remaining steps are the same as in Example 2; In the treatment process of the supported ozone catalyst, S22 is omitted, and the ozone concentration is kept constant at 100 mg / L. The remaining steps are the same as in Example 2. Example

[0049] The performance detection and treatment effects of Example 2, Example 3, Example 4 and the blank control Example 5 are as follows: The detection results of catalyst characterization are as follows:

[0050] The detection results of printing and dyeing wastewater treatment data (inlet COD = 1000 mg / L, chromaticity = 6000 times) are as follows:

[0051] The detection results of dynamic response performance are as follows:

[0052] The performance detection and treatment effects show that: This supported ozone catalyst realizes the efficient synergy of intelligent pore size regulation and multi-field coupling catalysis through the ternary cooperative design of "environment-responsive medium - quantum dot modification - bioenzyme modification".

[0053] The environment-responsive porous medium is based on mesoporous alumina grafted and modified with poly-N-isopropylacrylamide. Its pore size can shrink / stretch intelligently within the range of 6 - 20 nm with the change of temperature from 10 - 48 °C and pH from 4 - 9, significantly improving the mass transfer efficiency by 40%.

[0054] The transition metal active centers modified with quantum dots enhance the absorption of visible light at 520 nm through the surface plasmon resonance effect, making the hydroxyl radical yield reach 1.32 - 1.58×10¹⁸ radicals / mL·min, an increase of 86 - 88% compared with the blank group.

[0055] The bioenzyme modification layer realizes in-situ regeneration of the biofilm through laccase mediators, maintaining the adsorption capacity above 180 mg / g and extending the catalyst stability to 380 - 450 hours.

[0056] The treatment process adopts the integrated technology of ultrasonic fragmentation - microwave intensification - ozone catalysis - magnetic membrane separation. Under the conditions of inlet COD = 1000 mg / L and chromaticity 6000 times, the COD removal rate of Example 3 reaches 95.2%, the decolorization rate reaches 99.5%, and the effluent BOD 5 / COD ratio is increased to 0.45, and the energy consumption is only 0.92 kWh / m³.

[0057] In the blank control group, due to the omission of quantum dots and microwave treatment, the pollutant removal rate decreased by 21 - 17% and the energy consumption increased by 41%, verifying the necessity of multi-technology synergy.

[0058] Process parameter optimization shows that the comprehensive performance is optimal when the mass ratio of template agent F127 to CTAB is 2:1, the quantum dot loading is 4.3%, and the grafting density is 1.2 mmol / g. The response time is shortened to 38 - 55 seconds, providing an efficient solution for the advanced treatment of printing and dyeing wastewater.

[0059] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention.

Claims

1. A supported ozone catalyst for treating printing and dyeing wastewater, characterized in that: The supported ozone catalyst includes an environmentally responsive porous medium, an active center and a bio-enzyme modified layer; The environmentally responsive porous medium is based on mesoporous alumina modified by poly (N-isopropylacrylamide) grafting, the initial pore size of the mesoporous alumina is 10-15 nm, the grafting rate of poly (N-isopropylacrylamide) is 12-20%, and has temperature responsive characteristics in the range of 25-40°C. The active center is composed of a transition metal active center and quantum dots modified thereon; The bio-enzyme modified layer is obtained by deeply bio-modifying the catalyst surface with laccase having redox activity.

2. A method for preparing a supported ozone catalyst for treating printing and dyeing wastewater, applicable to the supported ozone catalyst for treating printing and dyeing wastewater according to claim 1, characterized in that: The preparation method of the supported ozone catalyst is as follows: S1. A mesoporous alumina support was prepared by a template method, and then poly (N-isopropylacrylamide) was grafted onto the mesoporous alumina using surface-initiated atom transfer radical polymerization technology to obtain an environmentally responsive porous medium. S2, preparing a transition metal active center precursor solution, impregnating the environmentally responsive porous medium therein, so that the active center is loaded onto the medium, and then preparing a cadmium sulfide quantum dot solution by a hydrothermal synthesis method, and impregnating the environmentally responsive porous medium into the quantum dot solution to obtain a loaded medium with quantum dot-modified active centers; S3. Bio-enzyme-assisted surface modification to prepare a supported ozone catalyst.

3. The method for preparing a supported ozone catalyst for treating printing and dyeing wastewater according to claim 2, characterized in that: In S1, the following is also included: S11, the template agent is a compound system of block copolymer F127 and hexadecyltrimethylammonium bromide, with a mass ratio of 3:1; Aluminum nitrate nonahydrate and the template agent were ultrasonically dispersed in a mixed solvent of ethanol and water in a volume ratio of 7:3 for 30 minutes, and hydrothermally reacted at 80° C. for 24 hours. Before calcination, 0.1 M dilute hydrochloric acid was used for gradient elution to remove the template agent. S12, the initiator is 2-bromoisobutyryl bromide, which is bonded to the surface of alumina through a silane coupling agent KH570, and the grafting density is 0.8-1.2 mmol / g; The polymerization conditions are as follows: the concentration of the monomer N-isopropylacrylamide is 0.5 M, the molar ratio of the catalyst cuprous bromide / ligand pentamethyldiethylenetriamine is 1:2, and the reaction is carried out at 60° C. for 6 hours under nitrogen protection.

4. The method for preparing a supported ozone catalyst for treating printing and dyeing wastewater according to claim 2, characterized in that: In S2, it also includes the following: S21, respectively preparing solutions containing manganese, iron, and copper precursors, and mixing them evenly in a molar ratio of manganese: iron: copper = 2:1:1 to obtain a transition metal active center precursor solution; S22, immersing the environmentally responsive porous medium in a transition metal active center precursor solution, fully adsorbing under ultrasonic-assisted conditions, with the ultrasonic frequency set to 40 kHz, the ultrasonic power to 200 W, and the ultrasonic time to 30 minutes, followed by drying in a vacuum environment at 120°C for 12 hours, and then calcining in a muffle furnace at 500°C for 4 hours, so that the transition metal active center is firmly loaded on the medium; S23. A cadmium sulfide quantum dot solution with a particle size of 3 to 4 nm is prepared by a hydrothermal synthesis method. The medium loaded with transition metal active centers is immersed in the quantum dot solution. The solution is fully reacted under magnetic stirring to control the quantum dot loading amount to 3.5 to 4.5% of the total mass of the catalyst. The solution is then dried in an oven at 60°C for 8 hours to obtain a loaded medium with quantum dot-modified active centers.

5. The method for preparing a supported ozone catalyst for treating printing and dyeing wastewater according to claim 2, characterized in that: In S3, it also includes the following: S31, preparing a laccase solution with a concentration of 0.5-1.0 mg / mL, placing the loaded medium in the laccase solution, and treating in a shaker at a temperature of 32-34° C. and a rotation speed of 100-150 r / min for 2.5-3.5 hours; S32. After the treatment is completed, the medium is washed with deionized water for multiple times to remove unreacted laccase, and then dried in a vacuum drying oven at 40° C. for 10 hours to obtain the final supported ozone catalyst.

6. A treatment process of a supported ozone catalyst for treating printing and dyeing wastewater, using the supported ozone catalyst for treating printing and dyeing wastewater according to claim 1, characterized in that: The supported ozone catalyst treatment process includes the following: S1. Use ultrasonic and electrochemical technology to pre-treat printing and dyeing wastewater; S2. Using ozone and microwaves to achieve catalytic oxidation treatment of printing and dyeing wastewater through a fluidized bed reactor; S3. Adjust the medium pore size and catalytic reaction according to the changes in conditions during the printing and dyeing wastewater treatment stage; S4, realize in-situ regeneration of catalyst biofilm and stable performance control through biological enzymes; S5. Use magnetic separation and membrane treatment technology to separate solid and liquid and recycle resources of the treated printing and dyeing wastewater.

7. A treatment process of a supported ozone catalyst for treating printing and dyeing wastewater according to claim 6, characterized in that: In S1, the following is also included: S11, using 20kHz high-frequency ultrasonic treatment for 10 minutes, with an acoustic energy density of 0.8W / cm³, to break up the chains of macromolecular pollutants; S12, introducing CO2 microbubbles with a diameter of less than 50 μm to adjust the pH of the wastewater to 6.5±0.2, providing a neutral environment for the subsequent response of the responsive porous medium; In S2, it also includes the following: S21, in the initial stage, ozone is introduced at a concentration of 120 mg / L, and after 15 minutes, the concentration is reduced to 80 mg / L, and combined with microwave dynamic regulation, the active centers on the catalyst surface are alternately in a state of high concentration ozone adsorption and free radical generation; S22, using 2450MHz microwave pulse mode, duty cycle 2:1, average power 250W, at 35-40℃, the responsive porous medium poly (N-isopropylacrylamide) chain segments are stimulated to stretch to 18-20nm pore size, and the quantum dot photogenerated electron-hole pairs are activated at the same time.

8. The process for treating printing and dyeing wastewater using a supported ozone catalyst according to claim 6, characterized in that: In S3, it also includes the following: S31, at low temperature acidic stage of 15-20℃ and pH 4-5, the poly(N-isopropylacrylamide) chain segments shrink to 6-8nm pore size, adsorbing and enriching small molecular dyeing pollutants; In the high temperature alkaline stage of 35-40℃ and pH 8-9, the poly(N-isopropylacrylamide) chain segments stretch, the medium pore size increases to 18-20nm, and the adsorbed pollutants are released to the surface of the active center, promoting a 40% increase in mass transfer efficiency. S32. Under microwave excitation, cadmium sulfide quantum dots of 3 to 4 nm produce photogenerated electron-hole pairs, which enhance the absorption of visible light with a wavelength of 520 nm through the surface plasmon resonance effect, making the hydroxyl radical yield reach 1.2×1018radicals / mL・min.

9. The process for treating printing and dyeing wastewater using a supported ozone catalyst according to claim 6, characterized in that: In S4, it also includes the following: S41, after every 2 h of treatment, 0.1% ABTS solution was injected as laccase mediator and maintained at 32 °C for 30 min to restore the adsorption capacity of the biofilm for cationic dyes to more than 180 mg / g through enzymatic cross-linking reaction; S42. Real-time monitoring of biofilm protein concentration by UV-Vis spectroscopy at a wavelength of 280nm, automatic adjustment of activator dosage, ensuring that the biofilm thickness is stable at 50-80nm, and inhibiting the occurrence of side reactions.

10. The treatment process of a supported ozone catalyst for treating printing and dyeing wastewater according to claim 6, characterized in that: In S5, the following are also included: S51, the effluent is treated by ceramic membrane with pore size of 50nm and nanofiltration, the COD of the produced water is less than 50mg / L, the conductivity is less than 200μS / cm, and the reuse rate reaches 85%; S52. The concentrated liquid is evaporated and crystallized to recover inorganic salts, and the residue is purified by acid dissolution-extraction process to purify precious metals, with a recovery rate of more than 98%.

Images