Titanium-based nanoscale ozone oxidation catalyst, and preparation method and application thereof

Abstract

The application belongs to the technical field of catalysts, and relates to a titanium-based nanoscale ozone oxidation catalyst, in particular to an ozone oxidation catalyst for advanced treatment of industrial wastewater, and further discloses a preparation method and application thereof. The titanium-based nanoscale ozone oxidation catalyst comprises a rho-Al2O3 carrier and a NiO@TiO2 active component. The multi-metal oxide with the aluminum trioxide as the carrier has extremely high activity, is good in wastewater treatment effect, and is convenient to recycle and use. TiO2 contained in the active component is a catalyst widely applied at present, and plays an important role in sewage treatment and environmental pollution control.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, and relates to a titanium-based nanoscale ozone oxidation catalyst, more specifically to an ozone oxidation catalyst for deep treatment of industrial wastewater, and further discloses its preparation method and application. Background Technology

[0002] Water is a vital resource for human survival. According to UNESCO's "World Water Development Report 2021," global freshwater consumption increased sixfold from 1921 to 2021. However, with increasing wastewater discharge, water quality faces severe challenges, especially due to environmental degradation caused by industrialization, agricultural production, and urban life. The current water resource situation is extremely worrying and has already adversely affected human survival and social development. Reports indicate that global industrial activities discharge approximately 300-400 million tons of excessive heavy metals, persistent solvents, recalcitrant organic matter, bacteria, and pathogens into water bodies annually, posing a significant threat to human life. Currently, approximately 5 million people die each year from water-related diseases, and 200-300 million suffer from related illnesses. Clearly, industrial wastewater discharge poses a serious threat to the natural and living environment, and the treatment of recalcitrant industrial wastewater remains a difficult and urgent problem.

[0003] Traditional industrial wastewater treatment primarily relies on biological methods, which utilize microorganisms or their secretions to oxidize and decompose organic matter in the wastewater, thereby purifying it. While biological technologies offer advantages such as low cost, ease of operation, and large processing capacity, they still suffer from incomplete deep treatment of recalcitrant industrial organic wastewater, failing to achieve the desired purification effect. Therefore, there is an urgent need in this field for a targeted, effective, and efficient advanced wastewater treatment technology.

[0004] Currently, the main technologies for treating industrial organic wastewater include membrane treatment, ozone catalytic oxidation, and bioaugmentation. Among these, ozone catalytic oxidation has attracted much attention due to its strong oxidizing power and low pollution. Based on the catalyst morphology, catalytic ozonation can be divided into homogeneous catalytic ozonation (where the catalyst exists in the form of metal ions) and heterogeneous catalytic ozonation (where the catalyst is a solid metal oxide or a metal / metal oxide supported on a solid carrier). Heterogeneous catalytic ozone oxidation is the most effective method for treating industrial organic wastewater, offering advantages such as strong oxidizing power, simple operation, and small footprint. It can effectively mineralize recalcitrant organic matter and solve problems such as the difficulty in recovering homogeneous catalysts and secondary pollution. The main principle of heterogeneous catalytic ozone oxidation is as follows: ozone molecules are adsorbed at active sites on the catalyst surface and decomposed into more potent oxidizing free radicals such as hydroxyl radicals and superoxide radicals, which react with organic pollutants in the water, thereby achieving the mineralization of organic pollutants. Therefore, the key to the heterogeneous catalytic ozone oxidation process is a highly efficient catalyst, which has been extensively studied by researchers both domestically and internationally.

[0005] Currently, there are many types of commonly used heterogeneous catalysts, mainly including single-metal or multi-metal oxide catalysts containing Fe, Mn, Ce, Zn, Ti, etc., carbon-based non-metallic catalysts containing N, F, etc., and MOF catalysts. Among them, metal oxide catalysts are the most widely used due to their advantages such as low cost and simple synthesis process. For example, Chinese patent CN102258997A discloses a manganese-supported heterogeneous catalyst. Compared with the oxidation removal rate of pollutants by ozone alone, the water treatment method using the manganese-supported heterogeneous catalyst to catalyze ozone to produce highly active pentavalent manganese can improve the pollution removal efficiency by more than 70%. Another example is the synthesis of Fe-Cu@SiO2 by Chen et al., where the interfacial coupling between iron oxide and copper oxide and the strong interaction between the SiO2 shell and the metal improve the catalyst's stability and exhibit good TOC removal rate. Yet another example is the S-MgO catalyst prepared by introducing sulfur into MgO, which can achieve 100% removal of tetracycline and 86.4% TOC removal rate within 60 minutes.

[0006] However, the main problem with conventional catalysts is the loss of the active metal components, which can easily cause secondary pollution and increase the difficulty of subsequent treatment. To address this issue, researchers have focused on enhancing the bonding between the metal components and the support to improve catalyst stability and have actively explored the impact of different synthesis methods on catalyst stability. For example, Ahmadi et al. designed and synthesized a PAC@Fe3O4 catalyst by supporting magnetic Fe3O4 on a carbon support (PAC) and investigated its catalytic performance in ozone oxidation treatment of high-salt petrochemical wastewater (initial COD of about 362-400 mg / L). After 120 min of ozone oxidation, the PAC@Fe3O4 catalyst achieved COD and TOC removal rates of 75.3% and 50.3%, respectively, demonstrating good ozone catalytic oxidation performance. However, after repeated use, the COD and TOC removal efficiencies decreased to 58.3% and 41.1%, respectively, mainly due to the loss of Fe components from the surface active sites. During five cycles of use, the Fe leaching concentration was between 0.05-0.2 mg / L. In addition, during long-term ozone catalytic oxidation, trace amounts of active components of the catalyst may leach out due to factors such as collisions. If these components accumulate in water, they will still cause harm to the aquatic environment. Therefore, it is urgent to find a green and efficient metal component to replace conventional transition metal oxides as the active center for ozone catalytic oxidation. Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to provide a titanium-based nanoscale ozone oxidation catalyst, which has a simple preparation process, high catalytic efficiency, high stability, and can significantly reduce the treatment cost of ozone method;

[0008] The second technical problem to be solved by the present invention is to provide a method for preparing and applying the above-mentioned titanium-based nanoscale ozone oxidation catalyst.

[0009] To address the aforementioned technical problems, the present invention provides a titanium-based nanoscale ozone oxidation catalyst, wherein the catalyst comprises a p-Al2O3 support and a NiO@TiO2 active component.

[0010] Specifically, in the titanium-based nanoscale ozone oxidation catalyst, the p-Al2O3 support is a spherical support;

[0011] Preferably, the diameter of the p-Al2O3 support is 3.0-5.0 mm.

[0012] This invention also discloses a method for preparing the titanium-based nanoscale ozone oxidation catalyst, comprising the following steps:

[0013] (1) Take ρ-Al2O3 particles for pretreatment to obtain the required carrier for later use;

[0014] (2) Take Ni(NO3)2, urea and polyethylene glycol and add water to mix and react to obtain Ni(OH)2; continue to add titanium-based compound to carry out precipitation reaction, collect the solid and carry out amorphous TiO2 crystallization treatment to obtain the desired active component NiO@TiO2;

[0015] (3) The ρ-Al2O3 support is mixed with the NiO@TiO2 active component and then ground.

[0016] (4) Continue to add seeds and the molding raw materials obtained in step (3) for molding treatment. The resulting catalyst blank is dried to obtain the catalyst.

[0017] Specifically, in the preparation method of the titanium-based nano-scale ozone oxidation catalyst, the pretreatment step in step (1) includes cleaning and dust removal, surface deoxidation, vacuum drying, and calcination to remove impurities from the p-Al2O3 particles;

[0018] Preferably, the cleaning and dust removal step includes adding a 60-70 v / v% ethanol solution and performing a shaking cleaning step;

[0019] Preferably, the surface deoxidation step includes a treatment step of adding 40-50 wt% nitric acid solution;

[0020] Preferably, the temperature of the vacuum drying step is 100-120℃, and the drying time is 6-10 hours;

[0021] Preferably, the temperature of the roasting and impurity removal step is 350-400℃, and the roasting time is 2-5 hours.

[0022] Specifically, in the preparation method of the titanium-based nano-scale ozone oxidation catalyst, in step (2), the molar ratio of Ni(NO3)2, urea and polyethylene glycol is 1-2:5-10:1-2;

[0023] Preferably, the reaction temperature is 80-90°C.

[0024] Specifically, in the preparation method of the titanium-based nanoscale ozone oxidation catalyst, in step (2), the titanium-based compound includes tetrabutyl titanate;

[0025] Preferably, the precipitation reaction includes a step of stirring at 40-50°C for 12-24 hours and a step of precipitation for 1-3 hours.

[0026] Specifically, in the preparation method of the titanium-based nano-scale ozone oxidation catalyst, the amorphous TiO2 crystallization step in step (2) includes drying at 60-80℃ for 2-4 hours and calcining at 400-500℃ for 1-2 hours.

[0027] Specifically, in the preparation method of the titanium-based nano-scale ozone oxidation catalyst, step (2) further includes the step of adding the prepared Ni(OH)2 to anhydrous ethanol for ultrasonic dispersion.

[0028] Preferably, the volume of Ni(OH)2 used is 2‰-15‰ of the volume of ethanol;

[0029] Preferably, the active ingredient Ti in the titanium-based compound has a content of 0.01-0.95 mol / L in ethanol.

[0030] Specifically, in the preparation method of the titanium-based nano-scale ozone oxidation catalyst, step (3) includes a grinding step using a nano-grinding machine.

[0031] Preferably, the grinding step takes 20-30 minutes.

[0032] Specifically, in the preparation method of the titanium-based nanoscale ozone oxidation catalyst, in step (4), the seed includes p-Al2O3;

[0033] Preferably, the forming process is carried out at a rotation speed of 25-35 r / min and a forming time of 2-3 h;

[0034] Preferably, the diameter of the catalyst embryo is 6-8 mm;

[0035] Preferably, the drying step is performed at a temperature of 70-90°C for 6-10 days.

[0036] This invention also discloses the application of the titanium-based nanoscale ozone oxidation catalyst or the titanium-based nanoscale ozone oxidation catalyst prepared by the method in the field of ozone oxidation treatment of wastewater.

[0037] The titanium-based nanoscale ozone oxidation catalyst of this invention comprises a p-Al2O3 support and a NiO@TiO2 active component. Using p-Al2O3 as the support, the catalyst is prepared by modifying metal oxides. It can accelerate the decomposition of ozone. Ozone decomposition generates highly oxidizing hydroxyl radicals, which undergo substitution, addition, electron transfer, and bond breaking reactions with organic matter. This oxidation of organic pollutants is non-selective and does not cause secondary pollution. It can oxidize and degrade large, recalcitrant organic pollutants into low-toxicity or non-toxic small molecules, improving the biodegradability of wastewater.

[0038] The titanium-based nano-scale ozone oxidation catalyst of this invention contains TiO2, which is a widely used catalyst and plays an important role in wastewater treatment and environmental pollution control. Its good water solubility and catalytic performance are expected to solve the crisis in the fields of wastewater treatment and environmental treatment.

[0039] The titanium-based nanoscale ozone oxidation catalyst of this invention, using alumina as a support and employing a multi-metal oxide substrate, exhibits extremely high activity, resulting in excellent wastewater treatment performance and convenient recycling. Compared to traditional single-metal oxide catalysts, this invention's catalyst has a simple preparation process, high catalytic efficiency, and high stability, significantly reducing the treatment cost of ozone methods.

[0040] The titanium-based nanoscale ozone oxidation catalyst of this invention, when placed in an ozone reactor, can simultaneously perform direct ozone oxidation and indirect oxidation of intermediate products, representing an advanced oxidation technology that integrates multiple functions. Compared with traditional ozone and Fenton technologies, it offers advantages such as high pollutant removal efficiency, high ozone utilization, and no need for external reagents. Compared with traditional ozone oxidation catalysts, it features high catalytic activity, long catalyst life, and low operating costs.

[0041] The titanium-based nanoscale ozone oxidation catalyst of this invention can promote the conversion of ozone into hydroxyl radicals with stronger oxidizing power in the ozone oxidation process for wastewater treatment, thereby improving the wastewater treatment effect and rate. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1

[0045] The preparation method of the titanium-based nanoscale ozone oxidation catalyst described in this embodiment includes the following steps:

[0046] (1) Carrier preparation: ρ-Al2O3 particles were added to a 65% ethanol solution and washed by shaking at 30°C for three consecutive times to remove dust. The washed aluminum oxide was then added to a 45% nitric acid solution to remove the oxide layer on the surface. The solution was washed with pure water and then dried at 100°C for 8 hours in a vacuum drying oven. Finally, it was calcined at 350°C for 4 hours in a muffle furnace to remove organic impurities from the pores and surface, thus obtaining the pretreated carrier.

[0047] (2) Preparation of active component: Ni(NO3)2, urea, and polyethylene glycol were mixed in deionized water at a molar ratio of 1:5:1 and stirred continuously in a water bath at 80°C for 6 hours. After vacuum filtration, the mixture was washed with deionized water and ethanol to prepare Ni(OH)2. 0.15 g of Ni(OH)2 was ultrasonically dispersed in 200 mL of anhydrous ethanol for 20 min. While stirring magnetically, 2 mL of tetrabutyl titanate was added dropwise to the ethanol. The mixture was then stirred in a water bath at 45°C for 24 hours, precipitated for 2 hours, and the supernatant was removed. The resulting product was washed three times with ethanol and deionized water, respectively. The product was dried at 80°C for 4 hours and calcined at 450°C for 2 hours to crystallize amorphous TiO2. A NiO@TiO2 active component coated with TiO2 was prepared.

[0048] (3) Mixing: Weigh a certain amount of ρ-Al2O3 support and NiO@TiO2 active components, add them to a nano mill for grinding, grind for 30 minutes to ensure uniform mixing, and then sieve for later use.

[0049] (4) Molding and drying: Add ρ-Al2O3 as seed in the molding machine, spray a small amount of deionized water and then soak it at a certain speed of 30 r / min. Add the molding raw material mixed in step (3) and repeat the feeding process until a catalyst embryo with a diameter of 6 mm is obtained. This process takes 3.0 h. Dry the catalyst embryo at 80 °C for 8 days to fully dry the catalyst.

[0050] Example 2

[0051] The preparation method of the titanium-based nanoscale ozone oxidation catalyst described in this embodiment includes the following steps:

[0052] (1) Carrier preparation: ρ-Al2O3 particles were added to a 70% ethanol solution and washed by shaking at 35°C for three consecutive times to remove dust. The washed aluminum oxide was then added to a 50% nitric acid solution to remove the oxide layer on the surface. The solution was washed with pure water and then dried at 120°C for 6 hours in a vacuum drying oven. Finally, it was calcined at 400°C for 2 hours in a muffle furnace to remove organic impurities from the pores and surface, thus obtaining the pretreated carrier.

[0053] (2) Preparation of active component: Ni(NO3)2, urea, and polyethylene glycol were mixed in deionized water at a molar ratio of 1.5:8:2 and continuously stirred in a water bath at 90℃ for 5 h. After vacuum filtration, the mixture was washed with deionized water and ethanol to prepare Ni(OH)2. 0.2 g of Ni(OH)2 was ultrasonically dispersed in 200 mL of anhydrous ethanol for 20 min. While magnetically stirring, 5 mL of tetrabutyl titanate was added dropwise to the ethanol. The mixture was then stirred in a water bath at 50℃ for 24 h, precipitated for 3 h, and the supernatant was removed. The resulting product was washed three times with ethanol and deionized water, respectively. The product was dried at 80℃ for 2 h and calcined at 500℃ for 1 h to crystallize amorphous TiO2. The NiO@TiO2 active component coated with NiO was prepared.

[0054] (3) Mixing: Weigh a certain amount of ρ-Al2O3 support and NiO@TiO2 active components, add them to a nano mill for grinding, grind for 30 minutes to ensure uniform mixing, and then sieve for later use.

[0055] (4) Molding and drying: Add ρ-Al2O3 as seed in the molding machine, spray a small amount of deionized water and then soak it at a certain speed of 35 r / min. Add the molding raw material mixed in step (3) and repeat the feeding process until a catalyst embryo with a diameter of 8 mm is obtained. This process takes 3.0 h. Dry the catalyst embryo at 90 °C for 6 days to fully dry the catalyst.

[0056] Example 3

[0057] The preparation method of the titanium-based nanoscale ozone oxidation catalyst described in this embodiment includes the following steps:

[0058] (1) Carrier preparation: ρ-Al2O3 particles were added to a 60% ethanol solution and washed by shaking at 25°C for three consecutive times to remove dust. The washed aluminum oxide was then added to a 40% nitric acid solution to remove the oxide layer on the surface. The solution was washed with pure water and then dried at 100°C for 10 hours in a vacuum drying oven. Finally, it was calcined at 350°C for 5 hours in a muffle furnace to remove organic impurities from the pores and surface, thus obtaining the pretreated carrier.

[0059] (2) Preparation of active component: Ni(NO3)2, urea, and polyethylene glycol were mixed in deionized water at a molar ratio of 2:10:1.5 and continuously stirred in a water bath at 80°C for 6 hours. After vacuum filtration, the mixture was washed with deionized water and ethanol to prepare Ni(OH)2. 0.2 g of Ni(OH)2 was ultrasonically dispersed in 200 mL of anhydrous ethanol for 20 min. While magnetically stirring, 3 mL of tetrabutyl titanate was added dropwise to the ethanol. The mixture was then stirred in a water bath at 40°C for 12 hours, precipitated for 2 hours, and the supernatant was removed. The resulting product was washed three times with ethanol and deionized water, respectively. The product was dried at 60°C for 4 hours and calcined at 400°C for 2 hours to crystallize amorphous TiO2. A NiO@TiO2 active component coated with TiO2 was prepared.

[0060] (3) Mixing: Weigh a certain amount of ρ-Al2O3 support and NiO@TiO2 active components, add them to a nano mill for grinding, grind for 20 minutes to ensure uniform mixing, and then sieve for later use.

[0061] (4) Molding and drying: Add ρ-Al2O3 as seed in the molding machine, spray a small amount of deionized water and then soak it at a certain speed of 25 r / min. Add the molding raw material mixed in step (3) and repeat the feeding process until a catalyst embryo with a diameter of 7 mm is obtained. This process takes 2.0 h. Dry the catalyst embryo at 70℃ for 10 days to fully dry the catalyst.

[0062] Example 4

[0063] The preparation method of the titanium-based nanoscale ozone oxidation catalyst described in this embodiment includes the following steps:

[0064] (1) Carrier preparation: ρ-Al2O3 particles were added to a 65% ethanol solution and washed by shaking at 35°C for three consecutive times to remove dust. The washed aluminum oxide was then added to a 45% nitric acid solution to remove the oxide layer on the surface. The solution was washed with pure water and then dried at 100°C for 8 hours in a vacuum drying oven. Finally, it was calcined at 350°C for 4 hours in a muffle furnace to remove organic impurities from the pores and surface, thus obtaining the pretreated carrier.

[0065] (2) Preparation of active component: Ni(NO3)2, urea, and polyethylene glycol were mixed in deionized water at a molar ratio of 2:5:1 and continuously stirred in a water bath at 80°C for 6 hours. After vacuum filtration, the mixture was washed with deionized water and ethanol to prepare Ni(OH)2. 0.15 g of Ni(OH)2 was ultrasonically dispersed in 200 mL of anhydrous ethanol for 20 min. While magnetically stirring, 2 mL of tetrabutyl titanate was added dropwise to the ethanol. The mixture was then stirred in a water bath at 45°C for 24 hours, precipitated for 2 hours, and the supernatant was removed. The resulting product was washed three times with ethanol and deionized water, respectively. The product was dried at 80°C for 4 hours and calcined at 450°C for 2 hours to crystallize amorphous TiO2. A NiO@TiO2 active component coated with TiO2 was prepared.

[0066] (3) Mixing: Weigh a certain amount of ρ-Al2O3 support and NiO@TiO2 active components, add them to a nano mill for grinding, grind for 30 minutes to ensure uniform mixing, and then sieve for later use.

[0067] (4) Molding and drying: Add ρ-Al2O3 as seed in the molding machine, spray a small amount of deionized water and then soak it at a certain speed of 30 r / min. Add the molding raw material mixed in step (3) and repeat the feeding process until a catalyst embryo with a diameter of 6 mm is obtained. This process takes 3.0 h. Dry the catalyst embryo at 80℃ for 8 days to fully dry the catalyst.

[0068] Comparative Example 1

[0069] The preparation method of the ozone oxidation catalyst described in this comparative example is the same as that in Example 1, except that the catalyst support is different, which is activated carbon.

[0070] Comparative Example 2

[0071] The preparation method of the ozone oxidation catalyst described in this comparative example is the same as that in Example 1, except that the nitrogen source used in the preparation of the active component is different, and the nitrogen source is ammonium bicarbonate.

[0072] Comparative Example 3

[0073] The preparation method of the ozone oxidation catalyst described in this comparative example is the same as that in Example 1, except that the solvent used in the preparation of the active component is different; the solvent is propylene glycol.

[0074] Experimental Example

[0075] 1. Catalytic effect

[0076] Nine identical columnar reactors, each with an effective volume of 10L, were respectively filled with equal amounts of ordinary alumina spheres of the same particle size, commercially available supported ozone catalysts (using alumina as a support and titanium dioxide as the catalytic active component), and nano-sized ozone oxidation catalysts prepared in Examples 1-4 and Comparative Examples 1-3 of this invention. Under the same operating parameters, the wastewater from the coal gasification unit (COD: 500mg / L-1200mg / L) was subjected to advanced treatment. The process conditions were: wastewater pH 7-8, ozone dosage 0.2L / min, HRT 30min, and catalyst dosage 80%.

[0077] Table 1 shows a comparison of the catalytic effects of different ozone oxidation catalysts.

[0078] Table 1 Effect of catalytic effect

[0079] Packing type <![CDATA[Influent COD / (mg·L -1 )]]> <![CDATA[Effluent COD / (mg·L -1 )]]> COD removal rate / % Ordinary alumina balls 679 477 29.8 Commercially available ozone catalysts 558 302 45.9 Example 1 931 315 66.1 Example 2 780 309 60.4 Example 3 590 238 59.7 Example 4 931 354 62.0 Comparative Example 1 1038 502 51.6 Comparative Example 2 665 350 47.4 Comparative Example 3 1296 519 59.9

[0080] It is evident that, under the same operating conditions, the catalyst prepared in this invention exhibits a significantly higher catalytic effect than ordinary alumina balls. Compared to commercially available ozone catalysts using titanium dioxide as the active component, the COD removal rate is increased by nearly 20%, demonstrating the excellent catalytic performance of the ozone oxidation catalyst prepared in this invention. After 20 days, the dissolved Ni and Ti ions in the catalyst were 0.0021 mg / L and 0.00075 mg / L, respectively. These ion concentrations are far below the limits set by current national drinking water standards, indicating that the ozone oxidation catalyst prepared in this invention has good reusability and does not cause secondary pollution.

[0081] 2. Wastewater treatment effect

[0082] Eight identical columnar reactors, each with an effective volume of 10L, were filled with equal amounts of the nano-sized ozone oxidation catalysts prepared in Example 1 and Comparative Example 3 of this invention, with the same particle size. Several different wastewaters were subjected to advanced treatment under the same operating parameters: ozone dosage 0.2L / min, HRT 30min, and catalyst dosage 80%.

[0083] Table 2 shows the effluent treatment effects of wastewater biochemical ponds in different industries.

[0084] Table 2 Wastewater Treatment Efficacy

[0085]

[0086] As shown in Table 2, under certain operating conditions, the ozone oxidation catalyst prepared in this invention achieves a COD removal rate of 50-65% for different types of wastewater. Compared to the 20-35% COD removal rate of direct ozone oxidation, this represents an improvement of nearly 30%. Compared to the 30-46% COD removal rate of the ozone oxidation catalyst prepared in Comparative Example 3, this represents an improvement of 10%-20%. Furthermore, the ozone oxidation catalyst prepared in this invention exhibits broad-spectrum catalytic performance for the ozone oxidation degradation of antibiotics. After 18 days of continuous use, the catalyst's COD removal rate from wastewater did not show a significant decrease, remaining stable at 50.2%-62.8%, indicating good stability in application.

[0087] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A titanium-based nanoscale ozone oxidation catalyst, characterized in that, The catalyst comprises a p-Al2O3 support and a NiO@TiO2 active component with TiO2 coated on NiO.

2. The titanium-based nanoscale ozone oxidation catalyst according to claim 1, characterized in that, The p-Al2O3 support is a spherical support; The diameter of the ρ-Al2O3 support is 3.0-5.0 mm.

3. A method for preparing a titanium-based nanoscale ozone oxidation catalyst as described in claim 1 or 2, characterized in that, Includes the following steps: (1) Take ρ-Al2O3 particles for pretreatment to obtain the required carrier for later use; (2) Take Ni(NO3)2, urea and polyethylene glycol and add water to mix and react to obtain Ni(OH)2; continue to add titanium-based compound to carry out precipitation reaction, collect the solid and carry out amorphous TiO2 crystallization treatment to obtain the desired active component NiO@TiO2; (3) The ρ-Al2O3 support is mixed with the NiO@TiO2 active component and then ground. (4) Continue to add seeds and the molding raw materials obtained in step (3) for molding treatment. The resulting catalyst blank is dried to obtain the final product.

4. The preparation method of the titanium-based nanoscale ozone oxidation catalyst according to claim 3, characterized in that, In step (1), the pretreatment step includes cleaning and dust removal, surface deoxidation, vacuum drying, and calcination to remove impurities from the ρ-Al2O3 particles; The cleaning and dust removal steps include adding a 60-70 v / v% ethanol solution and then shaking the solution for cleaning. The surface deoxidation step includes a treatment step of adding 40-50 wt% nitric acid solution; The temperature of the vacuum drying step is 100-120℃, and the drying time is 6-10 hours. The temperature for the roasting and impurity removal step is 350-400℃, and the roasting time is 2-5 hours.

5. The preparation method of the titanium-based nanoscale ozone oxidation catalyst according to claim 3, characterized in that, In step (2), the molar ratio of Ni(NO3)2, urea and polyethylene glycol is 1-2:5-10:1-2; The reaction temperature is 80-90℃.

6. The preparation method of the titanium-based nanoscale ozone oxidation catalyst according to claim 5, characterized in that, In step (2), the titanium-based compound includes tetrabutyl titanate; The precipitation reaction includes a step of stirring at 40-50℃ for 12-24 hours and a step of precipitation for 1-3 hours.

7. The preparation method of the titanium-based nanoscale ozone oxidation catalyst according to claim 6, characterized in that, In step (2), the amorphous TiO2 crystallization step includes drying at 60-80℃ for 2-4 hours and calcining at 400-500℃ for 1-2 hours.

8. The preparation method of the titanium-based nanoscale ozone oxidation catalyst according to claim 3, characterized in that, In step (3), the grinding step includes grinding using a nano-grinding machine; The grinding step takes 20-30 minutes.

9. The method for preparing the titanium-based nanoscale ozone oxidation catalyst according to claim 3, characterized in that, In step (4), the seed includes p-Al2O3; The forming process is performed at a rotation speed of 25-35 r / min for 2-3 hours. The diameter of the catalyst embryo is 6-8 mm; The drying process is carried out at a temperature of 70-90℃ for 6-10 days.

10. The application of the titanium-based nanoscale ozone oxidation catalyst according to claim 1 or 2 or the titanium-based nanoscale ozone oxidation catalyst prepared by the method according to any one of claims 3-9 in the field of ozone oxidation treatment of wastewater.

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