CN113044949B - Sodium Persulfate Sustained Release Agent Suitable for Catalytic Oxidative Degradation of Antibiotics and Its Preparation and Application - Google Patents

Abstract

The invention discloses a sodium persulfate slow-release agent suitable for catalytic oxidation degradation of antibiotics, a preparation method thereof and application thereof in remediation of soil and underground water polluted by antibiotics. The sodium persulfate slow-release agent comprises the following raw materials by taking the total mass of the raw materials as 100 percent: 30-50% of paraffin, 30-50% of quartz sand, 1-4% of ordered mesoporous manganese oxide and 10-20% of sodium persulfate; the ordered mesoporous manganese oxide is prepared by a hard template method, and the template agent adopts SBA-15. The preparation method comprises the following steps: (1) adding paraffin into absolute ethyl alcohol, heating to 60-80 ℃, and after the paraffin is completely melted, sequentially adding a surfactant, quartz sand, ordered mesoporous manganese oxide and sodium persulfate into the paraffin under stirring; (2) and (3) cooling the molten material obtained in the step (1) to obtain the sodium persulfate slow release agent. The sodium persulfate slow release agent has the advantages of good coating effect, low release rate, good permeability and adsorptivity and good oxidative degradation characteristic.

Description

Sodium persulfate sustained-release agent suitable for catalytic oxidative degradation of antibiotics and its preparation and application

technical field

The invention relates to the technical field of soil and groundwater remediation, in particular to a sodium persulfate (Na ₂ S ₂ O ₈ ) slow-release agent suitable for catalyzing and oxidatively degrading antibiotics and its preparation and application.

Background technique

With the continuous development of economy and society, my country's soil and groundwater environment has been threatened by serious pollution in recent years. In particular, the complex geological characteristics of groundwater, the coating of soil, the dynamic action of groundwater and the synergy of microorganisms can hide pollutants here, which makes it particularly difficult to deal with pollutants in groundwater. If only relying on natural degradation, it will take hundreds to thousands of years for these organic pollutants to reach harmless level. Therefore, it is necessary to develop a practical and effective treatment method to solve soil and groundwater pollution.

In recent years, more and more antibiotics have been discharged into soil and groundwater, and how to solve antibiotic pollution has attracted the attention of scholars. Antibiotic pollutants represented by tetracycline, due to their stubborn characteristics and complex migration characteristics, make researchers often unable to deal with them. , Tetracycline will also use the characteristics of soil coating and other characteristics to continuously release pollution into groundwater, causing continuous pollution. Therefore, simple governance methods often cannot solve this problem well, and solving this problem has become the goal of many researchers.

Chemical oxidation slow-release agents came into being in this situation. For ordinary repair methods, slow-release agents can precisely target pollutants, have a long sustained release time, and can effectively treat pollutants. Those contaminants that are back-released from low-permeability aquifers, not only that, but also control the rate at which the amount of reactant is released. Chemical oxidative slow-release agents are expected to treat tetracycline in soil and groundwater.

Yang Yuan et al. studied the release properties of sodium persulfate-paraffin-silica sand sustained-release material and its degradation effect on 2,4-dinitrotoluene, which is expected to be used for in-situ chemical oxidation remediation of soil and groundwater ("Sodium Persulfate"). Release properties of sustained-release materials and their degradation effect on 2,4-dinitrotoluene", "Environmental Science Research", March 2020, Vol. 33, No. 3).

Zhang Lina's master's thesis "Research on the Activation of Sodium Persulfate by Ferric Oxide to Degrade Organic Pollutants in Groundwater" reported the effect of manganese dioxide and other transition metal oxides as activators to activate sodium persulfate to degrade 1,2-dichloropropane. But manganese dioxide has not been studied in depth.

SUMMARY OF THE INVENTION

In view of the deficiencies in the art, the present invention provides a sodium persulfate slow-release agent suitable for catalyzing and oxidatively degrading antibiotics. The sodium persulfate is used as the main oxidant and the ordered mesoporous manganese oxide is used as the catalyst. Efficiently catalyze the oxidative degradation of tetracycline and other antibiotics. In addition, the present invention uses paraffin as a carrier and adds quartz sand at the same time to enhance permeability and adsorption. The sodium persulfate slow-release agent has good coating effect, low release rate, good permeability and adsorption, and good oxidative degradation characteristics, and is especially suitable for repairing soil and groundwater polluted by antibiotic pollutants.

A sodium persulfate sustained-release agent suitable for catalyzing and oxidatively degrading antibiotics, calculated on the basis of the total mass of raw materials as 100%, the raw material composition includes:

The ordered mesoporous manganese oxide is prepared by a hard template method, and the template agent is SBA-15.

The study found that when ordinary commercial manganese dioxide was used as a catalyst in combination with sodium persulfate to treat antibiotics such as tetracycline, it could not produce a good catalytic oxidation effect. When the ordered mesoporous manganese oxide prepared by the hard template method using SBA-15 as a template agent of the present invention is used as a catalyst in combination with sodium persulfate to treat antibiotics such as tetracycline, the synergistic effect of the two shows a synergistic effect. The significantly better catalytic oxidation degradation performance of antibiotics such as tetracycline indicates that the ordered mesoporous manganese oxide of the present invention has an excellent catalytic effect on sodium persulfate, and can maximize the oxidation performance of sodium persulfate.

In order to better realize the catalytic function, preferably, the ordered mesoporous manganese oxide has a β-MnO ₂ crystal structure, contains Mn ⁴⁺ and Mn ³⁺ , and has a specific surface area of not less than 80 m ² /g. The ordered mesoporous manganese oxide with two interconvertible valence states of Mn ⁴⁺ and Mn ³⁺ has better catalytic performance and electron transfer and transfer ability.

The hard template method preferably adopts the "Nano-etching method to prepare manganese oxide mesoporous materials and their degradation of rhodamine in high-salt wastewater" published by Yan Kaixin et al. The method for preparing manganese oxide ordered mesoporous materials described in "B".

Specifically, the hard template method preferably comprises the steps:

(1) the manganese nitrate aqueous solution is added in the dehydrated alcohol suspension of SBA-15, after stirring and fully adsorbing, add ammonia water to adjust the pH of the reaction system to 10.5～11.5, continue to stir after 10～20min centrifugation, wash the solid product until neutral , calcined at 350～450℃ for 3～5h after drying at room temperature to obtain a calcined product;

(II) replacing SBA-15 with the calcined product, repeating step (I), and performing 1 to 3 iterations in this way to obtain a composite product;

(III) The composite product is uniformly dispersed in the sodium hydroxide solution, heated and boiled, reacted to remove SBA-15 under reflux conditions, centrifuged after the reaction, washed the solid precipitation until neutral, and vacuum-dried at 55～65 ℃ to obtain The ordered mesoporous manganese oxide.

The ordered mesoporous manganese oxide prepared by the above hard template method has high degree of order and high crystallinity, and has good adsorption and catalytic ability, especially for the process of sodium persulfate oxidation of tetracycline and other antibiotics. Strong stability in use.

Preferably, the mass ratio of the sodium persulfate to the ordered mesoporous manganese oxide is 5-10:1, more preferably 5-8:1. The addition amount of ordered mesoporous manganese oxide is positively correlated with the catalytic ability, but when the catalyst addition amount exceeds a certain proportion, the catalyst addition amount increases again, and its promotion effect on the catalytic reaction will be weakened.

The sodium persulfate slow-release agent of the present invention selects paraffin and quartz sand as mixed carriers, wherein: paraffin has good adhesion, is insoluble in water, and is an environmental protection material; quartz sand has good permeability and is a green environmental protection material. The mixed carrier increases the coating effect, permeability and adsorption of the sustained release agent.

The present invention also provides the preparation method of described sodium persulfate sustained-release agent, comprising the steps:

(1) adding paraffin into absolute ethanol, heating to 60～80 ℃, after the paraffin is completely melted, adding surfactant, quartz sand, ordered mesoporous manganese oxide and sodium persulfate to it under stirring;

(2) cooling the molten material obtained in step (1) to obtain the sodium persulfate sustained-release agent.

Since the melting temperature of the paraffin wax is in the range of 58-60° C., in step (1), the temperature of the system is controlled to be 60-80° C. when the paraffin wax is dissolved, so that the paraffin wax can be completely melted. Preferably, heating to 70-75° C. in step (1) is more conducive to the transfer of molten material in step (2) and facilitates subsequent cooling.

In step (1), the surfactant includes Span-80 and polyethylene glycol with a molecular weight of 4000, which plays an emulsifying effect. The mass ratio of Span-80 and polyethylene glycol is preferably 0.01-0.2:1. The mass ratio of the absolute ethanol and polyethylene glycol is preferably 1-20:1. Polyethylene glycol can also act as a dissolving aid to assist in dissolving paraffin.

Preferably, in step (1), the rotational speed of the stirring is 100-200 rpm, and the total stirring time is 5-30 min.

The molten slow-release agent is in a flowing state before molding, and once the temperature is lowered, the paraffin will condense faster, and the setting time will be less. In step (2), in order to make the sodium persulfate slow-release agent obtained by cooling have a fixed shape and size, the molten material obtained in step (1) can be poured into the mold for cooling to obtain the sodium persulfate slow-release agent. .

The specific size of the mold may be 1.0cm×1.0cm×1.0cm.

The principle of the above preparation method is: based on the controlled release technology and the microcapsule technology, the oxidant sodium persulfate and the catalyst ordered mesoporous manganese oxide are uniformly dispersed in the molten liquid with paraffin, quartz sand, etc. as the carrier by the melting condensation dispersion method. , adding anhydrous ethanol, polyethylene glycol, Span-80 and other reagents to assist the carrier, oxidant and catalyst to mix evenly and stably, and finally pour it into the mold while hot, cool and dry to form solid particles to achieve the purpose of slow release.

The invention also provides the application of the sodium persulfate slow-release agent in repairing soil and groundwater contaminated by antibiotics.

Preferably, the antibiotic is Tetracycline (TC for short). Studies have found that antibiotics such as tetracycline are very stable, and a single sodium persulfate cannot directly oxidize these antibiotics. The effective oxidative degradation of antibiotics such as tetracycline can only be achieved by the auxiliary catalytic action of a specific catalyst.

Compared with the prior art, the main advantages of the present invention include:

1) The sodium persulfate slow-release agent of the present invention uses sodium persulfate as the main oxidant, ordered mesoporous manganese oxide as the catalyst, paraffin as the carrier, and adds quartz sand at the same time to enhance permeability and adsorption. The ordered mesoporous manganese oxide has large specific surface area, high order degree and crystallinity, and has good recycling performance, and has a unique and excellent ability to catalyze the oxidation of tetracycline and other antibiotics by sodium persulfate; The sodium persulfate sustained-release agent has good coating effect, low release rate, good permeability and adsorption, and under the synergistic catalysis of the ordered mesoporous manganese oxide, the oxidative degradation performance is significantly improved, which can be used to repair tetracycline, etc. Soil and groundwater contaminated by antibiotic contaminants.

2) The preparation method of the sodium persulfate sustained-release agent of the present invention is based on the controlled release technology and the microcapsule technology, and the oxidant sodium persulfate and the catalyst ordered mesoporous manganese oxide are uniformly dispersed in paraffin, quartz sand, etc. In the molten liquid as the carrier, add anhydrous ethanol, polyethylene glycol, Span-80 and other reagents to assist the carrier and the oxidant to mix evenly and stably, and finally pour it into the mold while still hot, and cool and dry to form solid particles to achieve sustained release. the goal of.

3) The release rate of the sodium persulfate sustained-release agent of the present invention in water is significantly reduced, the permeability is enhanced, and the adsorption and oxidizing properties are enhanced; meanwhile, its release period becomes longer, and the release rate of the sustained-release agent is relatively stable, especially for TC polluted water. Soil and wastewater have good treatment effect.

Description of drawings

Fig. 1 is the real photo of the slow-release agent of embodiment 3;

Fig. 2 is the time variation diagram of the sustained-release agent static release sodium persulfate concentration of embodiment 3;

3 is a graph showing the relative concentration of tetracycline in the static repair experiment of the slow-release agent of Example 3 over time;

Fig. 4 is a graph showing the variation of sodium persulfate concentration with time in the dynamic release experiment of Example 3, in which CRM label represents the sustained-release agent of Example 3;

Fig. 5 is a graph of the relative concentration of tetracycline in the dynamic repair experiment of Example 3 over time, and the CRM label in the figure represents the sustained-release agent of Example 3;

Fig. 6 is the relative concentration change diagram of the different catalysts of Test Example 1 to the degradation of tetracycline;

Fig. 7 is the change diagram of the relative concentration of tetracycline in six hours of static repair of slow-release agents with different addition amounts of ordered mesoporous manganese oxide of Test Example 2;

Fig. 8 is that the slow-release agent of different wax-sand ratios of Test Example 3 is statically released six hours sodium persulfate concentration variation diagram;

FIG. 9 is a graph showing the concentration change of sodium persulfate in six hours of static release of slow-release agents with different addition amounts of sodium persulfate in Test Example 4.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. The operation method without specifying the specific conditions in the following examples is usually in accordance with the conventional conditions, or in accordance with the conditions suggested by the manufacturer.

The preparation method of ordered mesoporous manganese oxide in the specific embodiment:

(1) 4mL concentration is that the manganese nitrate aqueous solution of 50wt% is added in the 50mL dehydrated alcohol suspension containing 3g SBA-15, after 0 ℃ of stirring 4h fully adsorb, add ammonia water to adjust the pH of the reaction system to 11, continue to stir after 15min centrifugal Separation, washing the solid product until neutral, drying at room temperature and then calcining at 400 °C for 4 hours to obtain a calcined product;

(II) replacing SBA-15 with the calcined product, repeating step (I) to obtain a composite product;

(III) The composite product is uniformly dispersed in the sodium hydroxide solution of 200mL 2mol/L, heated and boiled, and SBA-15 is removed by reaction under reflux conditions, and the reaction is centrifuged after finishing, and the solid precipitation is washed until neutral, 60 ° C of vacuum The ordered mesoporous manganese oxide was obtained after drying for 24 hours.

Example 1

Use commercial manganese dioxide (Sinopharm Chemical Reagent Co., Ltd., analytical grade) as a catalyst to catalyze the degradation of tetracycline by sodium persulfate, and control the initial concentration of tetracycline to be 20 mg/L, catalyst = 0.1 g/L, Na ₂ S ₂ O ₈ = 2mmol/L.

Example 2

Using ordered mesoporous manganese oxide as a catalyst to catalyze the degradation of tetracycline by sodium persulfate, using the same test conditions as in Example 1, controlling the initial concentration of tetracycline to be 20mg/L, catalyst=0.1g/L, Na ₂ S ₂ O ₈ =2mmol/L.

Example 3

The slow-release agent was a mixed adsorption slow-release agent with a mass ratio of sodium persulfate, paraffin, quartz sand and mesoporous manganese dioxide of 4:12:12:0.5.

(1) Preparation of sustained release agent

Based on the microcapsule technology, the slow-release agent is prepared by melting condensation dispersion method. Take 12g of paraffin into a conical flask, add 20mL of absolute ethanol, and heat to 75°C in a water bath; when the paraffin is completely melted, add 1g of polyethylene glycol-4000 and 2 drops of Span-80, and stir well; press 4:12 Add 12g quartz sand, 0.5g ordered mesoporous manganese oxide and 4g sodium persulfate powder in sequence in a mass ratio of 12:0.5, and stir to disperse evenly; cm; after cooling and drying, a cube-shaped solid new sodium persulfate sustained-release agent can be obtained.

Figure 1 is a real photo of a sustained-release agent with a mass ratio of sodium persulfate, paraffin, quartz sand and mesoporous manganese dioxide of 4:12:12:0.5.

(2) Static release of sustained release agent

The principle of the static release experiment is to release the oxidant sodium persulfate in the slow-release agent by placing different sustained-release agents in the same liquid environment (water environment or organic solution environment), but no reaction occurs. In a certain period of time, set time points for sampling, and measure the concentration of sodium persulfate at different times with an ultraviolet spectrophotometer.

Take about 2.0g of solid slow-release agent and place it in a 250mL conical flask; add 250mL of water and start timing; quantitatively take 1mL of sample, 1mL of KI solution, and 1mL of _NaHCO3 solution in a 10mL colorimetric tube at regular intervals, and set the volume to constant volume. To 10mL, record the label (add blank sample), shake manually for 15min; use a spectrophotometer to measure the absorbance of sodium persulfate at 352nm; calculate its concentration and draw a line graph. Figure 2 shows the time-dependent change of the sodium persulfate concentration in the static release of the sustained-release agent.

(3) Static repair of slow release agent

To simulate static repair experiments, a representative antibiotic pollutant, tetracycline, was selected. In this experiment, sodium persulfate was used to treat the simulated groundwater that was slightly polluted by tetracycline, and sampling measurements were carried out at regular intervals. Ordered mesoporous manganese oxide catalyzed the oxidation of tetracycline by sodium persulfate with better treatment effect.

Prepare low-concentration tetracycline to act as polluted water; take 2g of the slow-release agent to be measured and place it in the reactor, add 100mL of polluted water, and the tetracycline content is 10mg/L; take samples at regular intervals, 5mL each time; use UV spectrophotometry The concentration of tetracycline in the sample was measured at 352 nm by the method, and the curve of the concentration change with time was drawn. The results are shown in Figure 3.

(4) Dynamic release and repair

The dynamic experiment is mainly to simulate the medium environment and flow velocity of groundwater, and conduct one-dimensional sand column experiments. In this case, the contaminated groundwater was rehabilitated with the mixed adsorption slow-release agent, and the remediation effect was observed. This experiment was performed in a one-dimensional sand column. The slow-release agent was a mixed adsorption slow-release agent with a mass ratio of sodium persulfate, paraffin, quartz sand and mesoporous manganese dioxide of 4:12:12:0.5.

Simulate the medium environment and flow rate of groundwater, and conduct one-dimensional sand column experiments. The experimental parameters simulate the groundwater environment settings. The permeability coefficient of the experimental column medium is 1.39×10 ^-2 cm/s; the water flow rate is set to 2mL/min; the diameter of the experimental column is R=5.0cm; the length of the experimental column is L=20cm, and the proportion of the slow-release agent is l ₁ =3.0cm, front buffer medium proportion l ₂ =1.0cm, actual medium proportion l ₃ =15.0cm, rear buffer medium proportion l ₄ =1.0cm.

Fill the one-dimensional sand column and saturate the water (or polluted water) in the one-dimensional sand column (200mL); put 2g sodium persulfate slow-release agent at the water inlet of the one-dimensional sand column; connect the one-dimensional sand column, water tank and peristalsis Pump; start the peristaltic pump; pump water at a flow rate of 2.0 mL/min; take regular samples after starting the peristaltic pump, and measure the sodium persulfate concentration (or tetracycline concentration) of each water sample; draw the sodium persulfate concentration (or tetracycline concentration) curve.

Dynamic release experiment: Saturate the water in the experimental column after filling the medium, and add 2g of slow-release agent or sodium persulfate powder equivalent to the quality of sodium persulfate in the 2g slow-release agent at the water inlet of the one-dimensional sand column. Let the water in the system be a sodium persulfate solution, and measure the change of its concentration with time. The variation of sodium persulfate concentration with time in the dynamic release experiment is shown in Figure 4.

Dynamic remediation experiment: Fill the experimental column medium with tetracycline-contaminated water with an initial concentration of 10 mg/L. Add 2g of slow-release agent or sodium persulfate powder equivalent to the mass of sodium persulfate in 2g of slow-release agent at the water inlet of the experimental column. Connect the peristaltic pump and the experimental column, and turn on the peristaltic pump for dynamic repair experiments. The tetracycline concentration in the dynamic repair experiment as a function of time is shown in Figure 5.

Example 4

The difference between the preparation method of the sustained-release agent and Example 3 is only that the amount of ordered mesoporous manganese oxide added is 0.3 g, and the remaining steps and conditions are the same.

Example 5

The difference between the preparation method of the sustained-release agent and Example 3 is only that the amount of ordered mesoporous manganese oxide added is 0.7 g, and the remaining steps and conditions are the same.

Example 6

The only difference between the preparation method of the sustained-release agent and Example 3 is that no ordered mesoporous manganese oxide is added and the amount of paraffin wax is 3 g, and the remaining steps and conditions are the same.

Example 7

The difference between the preparation method of the sustained-release agent and Example 6 is only that the amount of paraffin wax is 6 g, and the remaining steps and conditions are the same.

Example 8

The difference between the preparation method of the sustained-release agent and Example 6 is only that the amount of paraffin wax is 12 g, and the remaining steps and conditions are the same.

Example 9

The difference between the preparation method of the sustained-release agent and Example 8 is only that the amount of sodium persulfate is 2 g, and the remaining steps and conditions are the same.

Example 10

The difference between the preparation method of the slow-release agent and Example 9 is only that the amount of sodium persulfate is 6 g, and the remaining steps and conditions are the same.

Test Example 1

Figure 6 shows the effect of different catalysts in Examples 1 and 2 on the degradation of tetracycline. It can be seen that different catalytic materials have different catalytic activities on sodium persulfate, and the ordered mesoporous manganese oxide of the present invention has significantly better catalytic activities. Commercial manganese dioxide has no ordered mesoporous structure, small specific surface area and weak catalytic performance, while the ordered mesoporous manganese oxide of the present invention shows good performance, and can adsorb a large amount of tetracycline while allowing persulfuric acid to be absorbed. Sodium and tetracycline are fully contacted and reacted; and a large number of Mn ³⁺ /Mn ⁴⁺ pairs are observed in the ordered mesoporous manganese oxide material, so it has good catalytic performance, so ordered mesoporous manganese oxide is selected as the catalyst. Catalytic material in release agent.

Test case 2

In order to study the influence of the addition amount of ordered mesoporous manganese oxide on the effect of the slow-release agent, a total of 4 kinds of slow-release agents in Examples 3 to 5 and Example 8 were selected for static repair experiments. Figure 7 shows the changes of tetracycline after static repair of slow-release agents with different proportions of ordered mesoporous manganese oxide for six hours. It can be seen that the blank control group without ordered mesoporous manganese oxide has almost no degradation effect on tetracycline. It can be seen that the simple addition of sodium persulfate has almost no oxidative degradation effect on tetracycline due to its too stability. To activate sodium persulfate to generate SO ₄ ^- · to oxidize tetracycline. Moreover, as long as a trace amount of ordered mesoporous manganese oxide is added, it can effectively catalyze sodium persulfate and degrade tetracycline. Further increase, the economic benefits will be reduced, for economic considerations, the amount of catalyst added should be consistent with the amount of oxidant. Therefore, it is necessary to control the addition ratio of mesoporous manganese dioxide to obtain the best effect.

Test case 3

In order to study the effect of different wax-sand ratios on the effect of slow-release agents, three kinds of slow-release agents in Examples 6, 7, and 8 were selected to carry out dynamic repair experiments. Figure 8 shows the changes of sodium persulfate in the static release of slow-release agents with different wax-sand ratios for six hours. It can be seen that the wax-sand ratio has a great influence on the release performance of the slow-release agent. The more paraffin content in the slow-release agent, the slower the release rate of the slow-release agent. This is because the higher the paraffin content, the more compact the sustained-release agent is, and the slower the release of sodium persulfate is. When the wax-sand ratio was 1:1, the sustained-release agent showed good sustained-release performance.

Test Example 4

In order to study the effect of different oxidant contents on the effect of sustained-release agents, three kinds of sustained-release agents in Examples 8, 9, and 10 were selected to carry out dynamic repair experiments. shown. It can be seen that the more sodium persulfate is added, the faster the sodium persulfate is released during release. When the amount of sodium persulfate added was 2g, there was almost no release of sodium persulfate, which may be due to the tight paraffin coating, resulting in extremely low release efficiency. In the first hour, it can be seen that the release rate of the sustained-release agent changes from fast to slow, and then slowly reaches equilibrium. In the next 5 hours, the release rate is relatively stable, showing the excellent sustained-release characteristics of the sustained-release agent. It can be seen that the larger the oxidant load in the slow-release agent, the faster the release rate of the slow-release agent, which shows that the release concentration can be adjusted by changing the content of sodium persulfate in the slow-release agent, and the corresponding adjustment can be made according to the pollutant concentration of different sites. , to achieve the best governance effect.

In addition, it should be understood that after reading the above description of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims (8)

1. The sodium persulfate slow-release agent suitable for catalytic oxidation degradation of antibiotics is characterized by comprising the following raw materials by taking the total mass of the raw materials as 100 percent:

30 to 50 percent of paraffin,

30-50% of quartz sand,

1 to 4 percent of ordered mesoporous manganese oxide,

10% -20% of sodium persulfate;

the ordered mesoporous manganese oxide is prepared by a hard template method, and a template agent adopts SBA-15;

the ordered mesoporous manganese oxide is beta-MnO₂Crystal structure of Mn-containing⁴⁺And Mn³⁺Specific surface area of not less than 80m²/g；

The mass ratio of the sodium persulfate to the ordered mesoporous manganese oxide is 5-10: 1;

the hard template method comprises the following steps:

(I) adding a manganese nitrate aqueous solution into an absolute ethyl alcohol suspension of SBA-15, stirring for full adsorption, adding ammonia water to adjust the pH value of a reaction system to 10.5-11.5, continuously stirring for 10-20 min, then carrying out centrifugal separation, washing a solid product until the solid product is neutral, drying at normal temperature, and calcining at 350-450 ℃ for 3-5 h to obtain a calcined product;

(II) replacing SBA-15 with the calcined product, repeating the step (I), and carrying out 1-3 iterations in total to obtain a composite product;

(III) uniformly dispersing the composite product in a sodium hydroxide solution, heating and boiling, reacting under a reflux condition to remove SBA-15, centrifugally separating after the reaction is finished, washing solid precipitate until the solid precipitate is neutral, and drying in vacuum at 55-65 ℃ to obtain the ordered mesoporous manganese oxide.

2. The process for producing a sodium persulfate sustained-release agent according to claim 1, which comprises the steps of:

(1) adding paraffin into absolute ethyl alcohol, heating to 60-80 ℃, and after the paraffin is completely melted, sequentially adding a surfactant, quartz sand, ordered mesoporous manganese oxide and sodium persulfate into the paraffin under stirring;

(2) and (3) cooling the molten material obtained in the step (1) to obtain the sodium persulfate slow release agent.

3. The method for preparing a sodium persulfate sustained-release agent according to claim 2, wherein in the step (1), the surfactant comprises span-80 and polyethylene glycol with the molecular weight of 4000, the mass ratio of span-80 to polyethylene glycol is 0.01-0.2: 1, and the mass ratio of anhydrous ethanol to polyethylene glycol is 1-20: 1.

4. The method for preparing a sodium persulfate slow-release agent as defined in claim 2, wherein in the step (1), the temperature is raised to 70 to 75 ℃.

5. The method for preparing a sodium persulfate slow-release agent according to claim 2, wherein in the step (1), the rotation speed of the stirring is 100 to 200rpm, and the total stirring time is 5 to 30 min.

6. The process for producing a sodium persulfate slow-release agent as described in claim 2, wherein in the step (2), the molten material obtained in the step (1) is poured into a mold and cooled to obtain the sodium persulfate slow-release agent.

7. The use of the sodium persulfate slow-release formulation according to claim 1 for remediating antibiotic-contaminated soil and groundwater.

8. The use of claim 7, wherein the antibiotic is tetracycline.

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