Heterogeneous ozone catalyst as well as preparation method and application thereof

Abstract

The invention provides a heterogeneous ozone catalyst as well as a preparation method and application thereof, and belongs to the field of sewage treatment. The heterogeneous ozone catalyst provided by the invention comprises a porous carrier and diboron trioxide loaded on the porous carrier, the diboron trioxide has oxygen defects. According to the heterogeneous ozone catalyst disclosed by the invention, diboron trioxide is subjected to range limitation, and the removal rate of pollutants in sewage by the range-limited heterogeneous ozone catalyst can reach 99%; the removal rate of pollutants in organic wastewater with different pH values is higher than 85%, the removal rate of pollutants in organic wastewater with different anions is higher than 90%, and the composite material has good stability and high degradation rate on organic matters.

Description

Technical Field

[0001] The invention relates to the field of sewage treatment, and in particular to a heterogeneous ozone catalyst and a preparation method and application thereof. Background Art

[0002] With the accelerated development of my country's industrialization process, the amount of industrial wastewater has increased sharply and the types of pollutants have become more diverse, posing a major challenge to ecological environmental safety and human health. The stubborn organic matter and toxic substances in industrial wastewater have become a problem for traditional biological treatment. Advanced oxidation technology (AOP) has become a universal technology in the field of industrial wastewater treatment because it can produce strong oxidizing free radicals. Among them, ozone has a very high redox potential (2.1V) and can quickly oxidize and decompose organic matter and microorganisms in water by direct oxidation or indirect production of strong oxidizing free radicals. At the same time, it does not cause secondary pollution and is used as a commonly used oxidation method in advanced oxidation technology (AOP).

[0003] However, ozone oxidation is selective and it is difficult to oxidize pollutants that do not contain electron-rich groups. In addition, differences in water quality can lead to unstable ozone oxidation effects. Ozone decomposes faster in water than in air, and its slow mass transfer rate and low solubility in sewage result in very low ozone utilization and high system energy consumption, which in turn hinders the further development of ozone technology.

[0004] Heterogeneous ozone catalysis is one of the most effective means to improve ozone utilization. However, the active components of the catalysts used in heterogeneous ozone catalysis are generally metal oxides, but metal oxides have problems such as low gas-solid-liquid three-phase mass transfer rate, easy deactivation of catalytic active sites, secondary dissolution of catalysts, and great influence of water pH value, which lead to low catalytic degradation efficiency and instability. Summary of the invention

[0005] The purpose of the present invention is to provide a heterogeneous ozone catalyst and its preparation method and application. The heterogeneous ozone catalyst provided by the present invention is more stable, can be applied to the catalysis of water with different pH values, and has a high degradation rate for organic matter.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The invention provides a heterogeneous ozone catalyst, comprising a porous carrier and boron trioxide loaded on the porous carrier; the boron trioxide has oxygen defects.

[0008] Preferably, the loading amount of the boron trioxide inside and on the surface of the porous carrier is 1 to 5 wt%.

[0009] Preferably, the boron trioxide is supported inside and on the surface of the porous carrier.

[0010] The present invention also provides a method for preparing the heterogeneous ozone catalyst described in the above technical solution, comprising the following steps:

[0011] (1) mixing a substrate, boron trioxide and a sodium hydroxide solution to obtain a pretreated material; the substrate is fly ash and / or distiller's grains containing organic matter;

[0012] (2) mixing the pretreated material obtained in step (1) with sodium hydroxide and calcining the mixture to obtain a calcined material;

[0013] (3) The calcined material obtained in step (2) is mixed with a solvent and subjected to a hydrothermal reaction to obtain a heterogeneous ozone catalyst.

[0014] Preferably, in step (1), the mass ratio of the matrix to the boron trioxide is (20-100):1.

[0015] Preferably, the mixing time in step (1) is 0.5 to 10 hours.

[0016] Preferably, in step (2), the mass ratio of the pretreated material to sodium hydroxide is 1:(2-3).

[0017] Preferably, the calcination temperature in step (2) is 700-900° C., and the calcination time is 1-3 hours.

[0018] Preferably, the temperature of the hydrothermal reaction in step (3) is 100-120° C., and the time of the hydrothermal reaction is 6-8 hours.

[0019] The present invention also provides the use of the heterogeneous ozone catalyst described in the above technical solution or the heterogeneous ozone catalyst prepared by the preparation method described in the above technical solution in catalyzing ozone degradation of organic pollutants.

[0020] The present invention provides a heterogeneous ozone catalyst, including a porous carrier and boron trioxide loaded inside and on the surface of the porous carrier; the boron trioxide has oxygen defects. The present invention uses boron trioxide as the active ingredient of the catalyst, and the boron trioxide has stable chemical properties, which can avoid the catalyst from being affected by the pH of the wastewater, and the boron trioxide has oxygen defects, which can effectively improve the efficiency of boron trioxide catalyzing ozone, improve the decomposition ability of ozone, and generate a large number of hydroxyl radicals, thereby efficiently degrading organic matter in the wastewater; the boron trioxide is loaded inside and on the surface of the porous carrier, and the pore structure in the porous carrier can confine the boron trioxide, which reduces the dissolution of boron trioxide in the catalyst to a certain extent, thereby reducing secondary pollution, and can also more efficiently utilize the active ingredient (boron trioxide) in the catalyst, thereby improving the degradation rate of organic pollutants. The results of the examples show that the heterogeneous ozone catalyst provided by the present invention can achieve a removal rate of 99% for pollutants in sewage; the removal rate of pollutants in organic wastewater with different pH values ​​is higher than 85%, and the removal rate of pollutants in organic wastewater with different anions is higher than 90%, and it has good stability and a high degradation rate for organic matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a curve diagram of the removal rate of tetracycline in organic wastewater of Application Example 1, Comparative Application Example 1 and Comparative Application Example 2 of the present invention;

[0022] Figure 2 It is a curve diagram of the removal rate of tetracycline in organic wastewater in Application Examples 2 to 4 of the present invention;

[0023] Figure 3 It is a curve diagram of the removal rate of tetracycline in organic wastewater of Application Examples 5 and Application Examples 6 to 8 of the present invention;

[0024] Figure 4 It is a curve diagram of the removal rate of tetracycline in organic wastewater of Application Examples 5 and Application Examples 9 to 11 of the present invention. DETAILED DESCRIPTION

[0025] The invention provides a heterogeneous ozone catalyst, comprising a porous carrier and boron trioxide loaded on the porous carrier.

[0026] In the present invention, the diboron trioxide is preferably loaded inside and on the surface of a porous carrier; the diboron trioxide has oxygen defects. The present invention limits the diboron trioxide to diboron trioxide with oxygen defects and limits the loading position of the diboron trioxide in the porous carrier to the above range, which can further improve the catalytic efficiency of the catalyst and the degradation rate of organic matter.

[0027] In the present invention, the loading amount of the diboron trioxide on the porous carrier is preferably 1-5wt%, more preferably 2-4wt%; the present invention limits the loading amount of the diboron trioxide on the porous carrier to the above range, which can further improve the catalytic efficiency of the catalyst for ozone, and thus improve the degradation rate of the catalyst for pollutants.

[0028] The invention adopts diboron trioxide as the active component of the catalyst. The diboron trioxide has stable chemical properties and can avoid the catalyst being affected by the pH value of the wastewater. The diboron trioxide has oxygen defects and can effectively improve the efficiency of diboron trioxide in catalyzing ozone, improve the decomposition ability of ozone, generate a large number of hydroxyl radicals, and thus efficiently degrade organic matter in the wastewater. The diboron trioxide is loaded inside and on the surface of a porous carrier, and the pore structure in the porous carrier can confine the diboron trioxide, thereby reducing the dissolution of diboron trioxide in the catalyst to a certain extent, thereby reducing secondary pollution, and can more efficiently utilize the active component (diboron trioxide) in the catalyst, thereby improving the degradation rate of organic pollutants.

[0029] The present invention also provides a method for preparing the heterogeneous ozone catalyst described in the above technical solution, comprising the following steps:

[0030] (1) mixing a substrate, boron trioxide and a sodium hydroxide solution to obtain a pretreated material;

[0031] (2) mixing the pretreated material obtained in step (1) with sodium hydroxide and calcining the mixture to obtain a calcined material;

[0032] (3) The calcined material obtained in step (2) is mixed with a solvent and subjected to a hydrothermal reaction to obtain a heterogeneous ozone catalyst.

[0033] The present invention mixes a matrix, boron trioxide and a sodium hydroxide solution to obtain a pretreated material.

[0034] In the present invention, the matrix is ​​fly ash and / or distiller's grains containing organic matter, preferably a mixture of fly ash and distiller's grains or fly ash. The present invention limits the type of the matrix to the above range, and solid waste can be used to reduce environmental pollution, and the organic matter contained in the fly ash and / or distiller's grains is used to carbonize the organic matter in the matrix during the subsequent calcination process, so that the obtained calcined material has a certain pore structure.

[0035] The present invention has no special limitation on the addition ratio of the fly ash and distiller's grains, and they can be mixed in any ratio. As an embodiment of the present invention, when the matrix is ​​fly ash and distiller's grains, the mass ratio of the fly ash and distiller's grains can be 1:1.

[0036] In the present invention, the mass ratio of the substrate to the boron trioxide is preferably (20-100): 1, more preferably (40-80): 1, and further preferably (50-60): 1. The present invention limits the mass ratio of the substrate to the boron trioxide to the above range so that the catalyst contains a suitable proportion of catalytically active substances (boron trioxide) and improves the catalytic efficiency of the catalyst for ozone.

[0037] In the present invention, the concentration of the sodium hydroxide solution is preferably (2-4) mol / L, more preferably 3 mol / L; the solvent in the sodium hydroxide solution is preferably deionized water. The present invention has no special restrictions on the addition ratio of the sodium hydroxide solution, as long as the matrix and the boron trioxide are completely immersed. The present invention limits the concentration of the sodium hydroxide solution to the above range so that the sodium hydroxide can better enter the interior of the matrix, which is conducive to the subsequent formation of small and abundant pores in the matrix.

[0038] In the present invention, the mixing time is preferably 0.5 to 10 hours, more preferably 6 to 10 hours. The present invention limits the mixing time to the above range to ensure uniform mixing of the materials.

[0039] In the present invention, the mixing is preferably a first mixing of the matrix and boron trioxide, followed by a second mixing with a sodium hydroxide solution.

[0040] In the present invention, the first mixing is preferably ball milling; the first mixing time is preferably 50 to 70 minutes, more preferably 60 minutes. The present invention has no special requirements on the speed of the ball milling, and the ball milling speed commonly used by those skilled in the art can be used.

[0041] In the present invention, the second mixing is preferably performed under stirring conditions. The present invention has no particular limitation on the stirring speed, and any speed commonly used by those skilled in the art may be used.

[0042] As an embodiment of the present invention, the temperature during the second mixing can be 100°C; the second mixing time can be 6 to 9 hours. The present invention limits the temperature and time of the second mixing to the above ranges to ensure that the sodium hydroxide is fully in contact with the substrate.

[0043] In the present invention, cooling is preferably performed after the second mixing is completed.

[0044] The present invention has no special limitation on the cooling operation, and the product obtained by the second mixing can be cooled to room temperature by an operation well known to those skilled in the art.

[0045] After obtaining the pretreated material, the present invention mixes the pretreated material with sodium hydroxide and then calcines the mixture to obtain the calcined material.

[0046] In the present invention, the mass ratio of the pre-treated material to sodium hydroxide is preferably 1: (2-3), more preferably 1: (2.2-2.6), and further preferably 1: 2.4. In the present invention, limiting the mass ratio of the pre-treated material to sodium hydroxide to the above range can further improve the porosity of the matrix after calcination.

[0047] In the present invention, the mixing of the pre-treated material and the sodium hydroxide is preferably grinding. The present invention has no special restrictions on the operation and time of the grinding, and the pre-treated material and the sodium hydroxide can be fully mixed and uniformly using the grinding parameters and time commonly used by those skilled in the art.

[0048] In the present invention, the calcination is preferably carried out in an inert atmosphere; the inert atmosphere is preferably nitrogen or argon. In the present invention, the calcination temperature is preferably 700-900°C, more preferably 800-850°C; the calcination time is preferably 1-3h, more preferably 1.5-2h. The present invention limits the calcination temperature and time to the above ranges so that sodium hydroxide can react with carbon after pyrolysis of organic matter during the calcination process to generate sodium carbonate, water vapor and hydrogen, so that the matrix forms a porous structure, and promotes the formation of boron trioxide with oxygen defects by boron trioxide, thereby improving the efficiency of boron trioxide in catalyzing ozone.

[0049] After the calcination is completed, the calcined product is preferably ground to obtain a calcined material.

[0050] The present invention has no special limitation on the grinding operation, and the calcined product can be ground to a particle size less than 200 meshes.

[0051] After obtaining the calcined material, the present invention mixes the calcined material with a solvent and then performs a hydrothermal reaction to obtain a heterogeneous ozone catalyst.

[0052] In the present invention, the solvent is preferably water or anhydrous ethanol, more preferably water. As an embodiment of the present invention, when the solvent is water, the hydrothermal reaction is a hydrothermal reaction; when the solvent is anhydrous ethanol, the hydrothermal reaction is a solvothermal reaction. The present invention does not specifically limit the amount of the solvent added, as long as it can immerse the calcined material. In a specific embodiment of the present invention, the ratio of the mass of the calcined material to the volume of the solvent is 1g:4mL.

[0053] In the present invention, the mixing of the calcined material and the solvent is preferably stirred; the mixing time is preferably 1 to 3 hours, more preferably 2 hours. The present invention does not specifically limit the stirring speed, and the stirring speed commonly used by those skilled in the art can be used. The present invention can make the calcined material and the solvent mixed uniformly by stirring.

[0054] In the present invention, the hydrothermal reaction is preferably carried out in a reactor; the temperature of the hydrothermal reaction is preferably 100-120°C, more preferably 100-110°C; the time of the hydrothermal reaction is preferably 6-8h, more preferably 7-8h. In the present invention, limiting the temperature and time of the hydrothermal reaction to the above range can further increase the oxygen defects in the boron trioxide in the matrix and further improve the efficiency of the catalyst in catalyzing ozone.

[0055] After the thermal reaction is completed, the present invention preferably filters, washes and dries the product of the hydrothermal reaction in sequence to obtain a heterogeneous ozone catalyst.

[0056] The present invention has no special limitation on the filtering operation, and the hydrothermal reaction product can be separated into solid and liquid by using filtering means commonly used in the art.

[0057] The present invention has no special limitation on the washing liquid and the washing times. The solid product obtained by filtration can be washed to neutrality using a washing liquid commonly used by those skilled in the art.

[0058] As an embodiment of the present invention, the drying temperature may be 80° C. and the drying time may be 12 hours. The present invention removes moisture from the washed solid product by drying.

[0059] The present invention utilizes a matrix, boron trioxide and a sodium hydroxide solution for mixing, so that sufficient sodium hydroxide solution can be adsorbed in the matrix, thereby providing favorable conditions for the subsequent preparation of a porous carrier; organic matter in the matrix can be formed into carbon through calcination, and the matrix can form a rich pore structure through the action of sodium hydroxide, so that the boron trioxide can be confined; and the boron trioxide confined in the matrix is ​​formed into boron trioxide with oxygen defects through calcination and subsequent hydrothermal reaction, which can not only effectively improve the efficiency of boron trioxide in catalyzing ozone, thereby improving the utilization rate of ozone, but also reduce the dissolution of boron trioxide in the catalyst to a certain extent, thereby reducing secondary pollution.

[0060] The present invention also provides the use of the heterogeneous ozone catalyst described in the above technical solution or the heterogeneous ozone catalyst prepared by the preparation method described in the above technical solution in catalyzing the degradation of organic pollutants in an ozone system.

[0061] As an embodiment of the present invention, the use of the heterogeneous ozone catalyst in catalyzing the degradation of organic pollutants by an ozone system can be to use the heterogeneous ozone catalyst to catalyze the degradation of organic wastewater containing tetracycline by an ozone system.

[0062] As an embodiment of the present invention, the dosage of the heterogeneous ozone catalyst can be 0.2 g / L.

[0063] In the present invention, the ozone system preferably includes an O3 system, an O3+permonosulfate (PMS) system, an O3+peracetic acid system, an O3+H2O2 system or an O3+electrocatalytic system.

[0064] As an embodiment of the present invention, when the ozone system is an O3 system, the concentration of O3 in the organic wastewater can be 0.2 to 10 mg / L.

[0065] As an embodiment of the present invention, when the ozone system is an O3+permonosulfate (PMS) system, the concentration of O3 in the organic wastewater can be 0.2-10 mg / L, and the concentration of permonosulfate (PMS) can be 1.5 mM.

[0066] As an embodiment of the present invention, when the ozone system is an O3+peracetic acid system, the concentration of O3 in the organic wastewater can be 0.2-10 mg / L, and the concentration of peracetic acid can be 1.7 mM.

[0067] As an embodiment of the present invention, when the ozone system is an O3+H2O2 system, the concentration of O3 in the organic wastewater can be 0.2-10 mg / L, and the concentration of peracetic acid can be 5 mM.

[0068] As an embodiment of the present invention, when the ozone system is an O3+ electrocatalytic system, the concentration of O3 in the organic wastewater can be 0.2-10 mg / L, and the current density can be 10 mA / cm 2 .

[0069] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0070] Example 1

[0071] A heterogeneous ozone catalyst is composed of a porous carrier and boron trioxide loaded inside and on the surface of the porous carrier; the boron trioxide has oxygen defects;

[0072] The loading amount of the boron trioxide inside and on the surface of the porous carrier is 2 wt%;

[0073] The preparation method of the heterogeneous ozone catalyst:

[0074] (1) Fly ash and boron trioxide were ball-milled for 60 min at a mass ratio of 50:1 for a first mixing, and then stirred with a 3 mol / L sodium hydroxide solution for a second mixing (stirred at 100° C. for 9 h) and then cooled to obtain a pretreated material;

[0075] (2) grinding and mixing the pretreated material obtained in step (1) with sodium hydroxide solid in a mass ratio of 1:2.4, calcining at 800° C. for 1.5 h under a nitrogen atmosphere, and then grinding and passing through a 200-mesh sieve to obtain a calcined material;

[0076] (3) The calcined material obtained in step (2) is mixed with water in a ratio of 1 g:4 mL, and subjected to a hydrothermal reaction at 100° C. in a reactor for 8 h. After cooling, the mixture is filtered and washed, and the solid product is washed to neutrality, and dried at 80° C. for 12 h to obtain a heterogeneous ozone catalyst.

[0077] Example 2

[0078] A heterogeneous ozone catalyst is composed of a porous carrier and boron trioxide loaded inside and on the surface of the porous carrier; the boron trioxide has oxygen defects;

[0079] The loading amount of the boron trioxide in the porous carrier is 5wt%;

[0080] The only difference between the preparation method of the heterogeneous ozone catalyst and that of Example 1 is that in step (1), the mass ratio of fly ash to boron trioxide is 20:1, and the rest is the same as that of Example 1.

[0081] Example 3

[0082] A heterogeneous ozone catalyst is composed of a porous carrier and boron trioxide loaded inside and on the surface of the porous carrier; the boron trioxide has oxygen defects;

[0083] The loading amount of the boron trioxide inside and on the surface of the porous carrier is 2.5wt%;

[0084] The preparation method of the heterogeneous ozone catalyst is different from that of Example 1 only in that "fly ash and boron trioxide are ball-milled at a mass ratio of 50:1" in step (1) is replaced by "fly ash, vinasse and boron trioxide are ball-milled at a mass ratio of 20:20:1", and the rest is the same as Example 1.

[0085] Example 4

[0086] A heterogeneous ozone catalyst is composed of a porous carrier and boron trioxide loaded inside and on the surface of the porous carrier; the boron trioxide has oxygen defects;

[0087] The loading amount of the boron trioxide inside and on the surface of the porous carrier is 1.23wt%;

[0088] The only difference between the preparation method of the heterogeneous ozone catalyst and that of Example 3 is that in step (1), the mass ratio of fly ash, vinasse and boron trioxide is 40:40:1, and the rest is the same as that of Example 3.

[0089] Application Example 1

[0090] The heterogeneous ozone catalyst of Example 1 is added to the organic wastewater containing tetracycline to catalyze the O3 system to degrade tetracycline; the dosage of the heterogeneous ozone catalyst is 0.2 g / L; the O3 in the O3 system is prepared by an ozone generator; the gas source of the ozone generator is air; the concentration of O3 in the organic wastewater in the O3 system is 0.2 mg / L;

[0091] The concentration of tetracycline in the organic wastewater is 20 mg / L; the pH value of the organic wastewater is 6.01.

[0092] Application Example 2

[0093] The difference between Application Example 2 and Application Example 1 is that the heterogeneous ozone catalyst is the heterogeneous ozone catalyst of Example 2, and the rest is the same as Application Example 1.

[0094] Application Example 3

[0095] The heterogeneous ozone catalyst of Example 2 is added to the organic wastewater containing tetracycline to catalyze the O3+PMS system to degrade tetracycline; the dosage of the heterogeneous ozone catalyst is 0.2 g / L; the O3 in the O3 system is prepared by an ozone generator; the gas source of the ozone generator is air; the concentration of O3 in the organic wastewater in the O3+PMS system is 0.2 mg / L, and the concentration of PMS is 1.5 mM;

[0096] The concentration of tetracycline in the organic wastewater is 20 mg / L; the pH value of the organic wastewater is 6.01.

[0097] Application Example 4

[0098] The heterogeneous ozone catalyst of Example 2 is added to the organic wastewater containing tetracycline to catalyze the O3+ electrocatalytic system to degrade tetracycline; the dosage of the heterogeneous ozone catalyst is 0.2 g / L; the O3 in the O3 system is prepared by an ozone generator; the gas source of the ozone generator is air; the concentration of O3 in the organic wastewater in the O3+ electrocatalytic system is 0.2 mg / L, and the current density is 10 mA / cm 2 ;

[0099] The concentration of tetracycline in the organic wastewater is 20 mg / L; the pH value of the organic wastewater is 6.01.

[0100] Application Example 5

[0101] The difference between Application Example 5 and Application Example 3 is that the heterogeneous ozone catalyst of Example 3 is used, and the rest is the same as Application Example 3.

[0102] Application Example 6

[0103] The only difference between Application Example 6 and Application Example 5 is that the pH value of the organic wastewater is 2.0, and the rest is the same as Application Example 5.

[0104] Application Example 7

[0105] The only difference between Application Example 7 and Application Example 5 is that the pH value of the organic wastewater is 8.0, and the rest is the same as Application Example 5.

[0106] Application Example 8

[0107] The only difference between Application Example 8 and Application Example 5 is that the pH value of the organic wastewater is 10.0, and the rest is the same as Application Example 5.

[0108] Application Example 9

[0109] The only difference between Application Example 9 and Application Example 5 is that the organic wastewater also contains 5mM Cl - , the rest is the same as Application Example 5.

[0110] Application Example 10

[0111] The only difference between Application Example 10 and Application Example 5 is that the organic wastewater also contains NO with a concentration of 5 mM. 3- , the rest is the same as Application Example 5.

[0112] Application Example 11

[0113] The only difference between Application Example 11 and Application Example 5 is that the organic wastewater also contains 5mM CO3 2- , the rest is the same as Application Example 5.

[0114] Comparative application example 1

[0115] The only difference between Comparative Application Example 1 and Application Example 1 is that no heterogeneous ozone catalyst is added, and the rest is the same as Application Example 1.

[0116] Comparative Application Example 2

[0117] The only difference between Comparative Application Example 2 and Application Example 1 is that the heterogeneous ozone catalyst is boron trioxide, and the rest is the same as Application Example 1.

[0118] After adding the catalysts of Application Examples 1 to 11 and Comparative Application Examples 1 to 2 to organic wastewater, 1 mL of samples were taken at 2 min, 5 min, 10 min, 15 min, 20 min, 25 min and 30 min of reaction, methanol was added to quench the active species, and high performance liquid chromatography (HPLC) was used to test the removal of tetracycline. The removal rate of tetracycline was expressed as C / C0.

[0119] The removal rates of tetracycline in organic wastewater in application example 1, comparative application example 1 and comparative application example 2 are as follows: Figure 1 As shown, from Figure 1 It can be seen that the removal rate of tetracycline in Application Example 1 (the curve is marked as confined B2O3+O3) can reach up to 72.3%. The removal rates of tetracycline in Comparative Application Example 1 without adding a heterogeneous ozone catalyst (the curve is marked as O3) and Comparative Application Example 2 using boron trioxide as a catalyst (the curve is marked as B2O3+O3) are 18.2% and 59.3% respectively, which are relatively low.

[0120] Application Examples 2-4 The removal rate of tetracycline in organic wastewater is as follows Figure 2 As shown, from Figure 2 It can be seen that the removal rate of tetracycline in the O3 system (the curve is recorded as confined B2O3+O3) is 78.2%, the removal rate of tetracycline in the O3+PMS system (the curve is recorded as confined B2O3+PMS) is 97.8%, and the removal rate of tetracycline in the O3+electrocatalytic system (the curve is recorded as confined B2O3+electrocatalytic) is 99%. The heterogeneous ozone catalyst of the present invention has a good degradation rate for pollutants in different ozone catalytic systems.

[0121] The removal rate of tetracycline in organic wastewater in Application Examples 5 and 6-8 is as follows: Figure 3 As shown, from Figure 3 It can be seen that the removal rate of tetracycline is 86.3% when the pH of organic wastewater is 2.0, the removal rate of tetracycline is 91.7% when the pH of organic wastewater is 8.0, the removal rate of tetracycline is 98.8% when the pH of organic wastewater is 6.1, and the removal rate of tetracycline is 89.9% when the pH of organic wastewater is 10.0. The initial pH of organic wastewater has little effect on the degradation effect of tetracycline, and the removal rate within 30 minutes is higher than 85%, indicating that the heterogeneous ozone catalyst of the present invention has a good degradation rate for pollutants in different pH environments.

[0122] The removal rate of tetracycline in organic wastewater in Application Examples 5 and 9-11 is as follows: Figure 4 As shown, from Figure 4 It can be seen that the removal rate of tetracycline when the organic wastewater does not contain salt anions (the curve is marked as Control) is 97.8%. -The removal rate of tetracycline was 98.1% and the anion in organic wastewater was CO3 2- The removal rate of tetracycline was 95.7%, and the anion in organic wastewater was NO 3- The removal rate of tetracycline was 91.1%, and the anion NO 3- 、CO3 2- It has a slight inhibitory effect on the degradation of tetracycline by the ozone system, while Cl - There is a certain promoting effect, and the removal rate in 30 minutes is higher than 90%, indicating that the heterogeneous ozone catalyst of the present invention has a good degradation rate for pollutants in different anion environments.

[0123] The heterogeneous ozone catalyst provided by the present invention is used to treat antibiotic pollutants, and the removal rate of pollutants in sewage can reach 99%; the removal rate of pollutants in organic wastewater with different pH values ​​is higher than 85%, and the removal rate of pollutants in organic wastewater with different anions is higher than 90%, and the catalyst has good stability and a high degradation rate for organic matter.

[0124] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A heterogeneous ozone catalyst, comprising a porous carrier and boron trioxide supported on the porous carrier; the boron trioxide has oxygen defects.

2. The heterogeneous ozone catalyst according to claim 1, characterized in that: The loading amount of the boron trioxide on the porous carrier is 1 to 5 wt %.

3. The heterogeneous ozone catalyst according to claim 1 or 2, characterized in that: The boron trioxide is loaded inside and on the surface of the porous carrier.

4. The method for preparing the heterogeneous ozone catalyst according to any one of claims 1 to 3, comprising the following steps: (1) mixing a substrate, boron trioxide and a sodium hydroxide solution to obtain a pretreated material; the substrate is fly ash and / or distiller's grains containing organic matter; (2) mixing the pretreated material obtained in step (1) with sodium hydroxide and calcining the mixture to obtain a calcined material; (3) The calcined material obtained in step (2) is mixed with a solvent and subjected to a hydrothermal reaction to obtain a heterogeneous ozone catalyst.

5. The preparation method according to claim 4, characterized in that: In the step (1), the mass ratio of the substrate to the boron trioxide is (20-100):

1.

6. The preparation method according to claim 4, characterized in that: The mixing time in step (1) is 0.5 to 10 hours.

7. The preparation method according to claim 4, characterized in that: In the step (2), the mass ratio of the pretreated material to the sodium hydroxide is 1:(2-3).

8. The preparation method according to claim 4, characterized in that: In the step (2), the calcination temperature is 700-900° C., and the calcination time is 1-3 hours.

9. The preparation method according to claim 4, characterized in that: The temperature of the hydrothermal reaction in step (3) is 100-120° C., and the time of the hydrothermal reaction is 6-8 hours.

10. Use of the heterogeneous ozone catalyst according to any one of claims 1 to 3 or the heterogeneous ozone catalyst prepared by the preparation method according to any one of claims 4 to 9 in catalytic ozone degradation of organic pollutants.

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