Preparation method and application of nanoscale enzyme composite preparation effervescent tablets for rapid degradation of organic pollutants

Abstract

The present application relates to a kind of preparation method and application of nanoscale enzyme composite preparation effervescent tablet for the rapid degradation of organic pollutants, the present application is prepared by water solution method, doping different proportions of Fe preparation MnO2 Nanoscale enzyme.After again, MnO2@Fe nanoscale enzyme and sodium percarbonate powder, MnO2@Fe nanoscale enzyme and sodium percarbonate are mixed and pressed into effervescent tablet, for quickly removing organic pollutants in water body.The nanoscale enzyme effervescent tablet obtained in the present application can quickly degrade low concentration organic pollution wastewater, improve the pH of acidic wastewater;Through sodium percarbonate reaction, dense micro-bubbles can be generated, which can mix catalyst and pollutants uniformly without using rotor to achieve the effect of rapid oxidation and degradation, and it is green and efficient, solves the problems such as cumbersome dosing, difficult reagent storage and other problems in engineering examples, and does not cause secondary pollution to water body when put into water body, greatly improves the efficiency of less amount of putting in engineering, and has wide application prospect.

Description

TECHNICAL FIELD

[0001] The application relates to a preparation method and application of a nanoscale enzyme composite preparation effervescent tablet for rapid degradation of organic pollutants, and belongs to the fields of chemistry and environment. BACKGROUND

[0002] At present, the rapid growth of global population and the environmental pressure brought by industrialization make pollutant control and environmental governance face severe challenges. Organic pollutants (such as industrial chemicals, dyes, medicines, antibiotics, etc.) are often detected in water environment, and with continuous accumulation, the water environment is seriously polluted, and the human life and health are threatened by the accumulation in the biological chain. The toxicity and non-biodegradability of some organic pollutants make the removal of organic pollutants always have the disadvantages of relatively long treatment time and complex treatment equipment. Therefore, it is urgent to develop a more efficient and simple treatment method to effectively remove the refractory organic pollutants in water. The advanced oxidation method can realize the zero environmental pollution and zero pollutant discharge by producing reactive oxygen species (ROS) and interacting with macromolecular organic pollutants to degrade them into small molecular organic matter or even completely mineralize, and has become a research hotspot at home and abroad due to the characteristics of wide oxidation range, short treatment cycle and fast degradation speed.

[0003] Compared with the traditional activated persulfate system, sodium percarbonate (SPC) has high stability and safety due to its unique physicochemical properties, is beneficial to transportation and has low cost; the pH application range is wider, which breaks through the limitation of the pH requirement of the traditional Fenton system; at the same time, the good buffering property of SPC also alleviates the pH fluctuation caused by acidic products. In addition, from the economic cost point of view, the price of SPC is lower than that of other commonly used oxidants such as H2O2, sodium monopersulfate and peroxodisulfate, which can save the treatment cost. However, the oxidation ability of sodium percarbonate (SPC) for pollutants is obviously weaker than that of persulfate, and because it is easy to be invalid due to moisture, it needs to be transported and stored in a dry environment, and the storage condition is strict. In the degradation of pollutants, the target pollutants degraded by the activated percarbonate advanced oxidation method at present mainly include antibiotics, dyes, pesticides and other typical pollutants, and the application range is small. Since sodium percarbonate (SPC) has low cost, the research on the degradation performance and conversion pathway of other types of organic pollutants, especially new pollutants, should be strengthened.

[0004] Meanwhile, as a new type of functional nanomaterial with enzymatic catalytic activity, the nanoenzyme has the advantages of simple preparation, low cost, high stability and adjustable activity compared with natural enzymes, and is concerned in the fields of environmental remediation, biological medicine and industry. The nanoenzyme itself has a certain catalytic capacity, can catalyze dissolved oxygen to produce singlet oxygen in solution, and is used for degrading organic pollutants. However, the existing nanoenzyme has the problems of few types, limited substrate selection, performance affected by apparent physical properties, and water body turbidity and even peculiar smell caused by excessive addition of the nanoenzyme into water body.

[0005] The addition of the compressed effervescent tablets effectively solves the problems of complicated steps and material waste in the prior art. The effervescent tablets are convenient and quick to use and long to store, and the efficiency of each process is improved. In addition, the effervescent tablets have a large density and can be settled at the bottom of the reaction tank to generate small and dense bubbles, so that the effervescent tablets can have an effect similar to aeration, save energy, and fully mix the reactants and the catalyst. The effervescent tablets combined with the removal of antibiotics and pollutants in wastewater have not been found, and an environmentally friendly material for removing common polluted wastewater still needs to be broken through. SUMMARY

[0006] In view of the deficiencies of the prior art, the application provides a preparation method and application of a nanoenzyme composite effervescent tablet for rapid degradation of organic pollutants.

[0007] To solve the above technical problems, the application realizes the technical solutions as follows:

[0008] A preparation method of a nanoenzyme composite effervescent tablet for rapid degradation of organic pollutants, comprising the following steps:

[0009] 1) Fe salt powder is added into a manganese sulfate monohydrate solution and stirred, then a potassium permanganate solution is slowly added drop by drop, and the obtained reaction product is repeatedly washed, dried, sieved, and MnO2@Fe nanoenzyme is obtained;

[0010] 2) The MnO2@Fe nanoenzyme obtained in step 1) and sodium percarbonate powder are mixed,

[0011] 3) The mixed powder obtained in step 2) is added into a mold and hot-pressed to form a nanoenzyme effervescent tablet.

[0012] According to the application, preferably, in step 1), the Fe salt powder is ferrous chloride powder or ferrous sulfate powder.

[0013] Most preferably, in step 1), the Fe salt powder is ferrous sulfate powder.

[0014] According to the application, preferably, in step 1), the concentration of the manganese sulfate monohydrate solution is 0.1-0.4 mmol / L; and the concentration of the potassium permanganate solution is 0.2-0.6 mmol / L.

[0015] According to the application, preferably, in step 1), the mass ratio of the iron salt powder to the manganese sulfate monohydrate in the manganese sulfate monohydrate solution is 1:7-1:2.

[0016] Further preferably, in step 1), the mass ratio of the iron salt powder to the manganese sulfate monohydrate in the manganese sulfate monohydrate solution is 1:5-1:2.

[0017] According to the application, preferably, in step 1), the volume ratio of the potassium permanganate solution to the manganese sulfate monohydrate solution is (1-4):(3-6).

[0018] According to the application, preferably, in step 1), the stirring time before adding acid is 10-20 min, the temperature is heated to 70℃ in an oil bath, a nitric acid solution with a mass concentration of 8-12% is slowly added dropwise, the temperature is maintained and stirred for 2-3 h, then a sodium hydroxide solution is added and stirred for 20-40 min, and then cooled to room temperature.

[0019] According to the application, preferably, in step 1), the volume ratio of the nitric acid solution to the manganese sulfate monohydrate solution is 1:(3-5).

[0020] According to the application, preferably, in step 1), the concentration of the sodium hydroxide solution is 0.1-0.3 mol / L; and the volume ratio of the sodium hydroxide solution to the manganese sulfate monohydrate solution is 1:(7-9).

[0021] According to the application, preferably, in step 2), the mass ratio of the MnO2@Fe nanoscale enzyme to the sodium percarbonate powder is (1-5):1.

[0022] According to the application, preferably, in step 2), the amount of sodium percarbonate is used to form an activated system in the water body with a concentration of 1-10 mM.

[0023] According to the application, preferably, in step 3), the hot pressing is performed by using a hot press, the temperature of the upper and lower pressing plates of the hot press is 15-25℃, the pressure is 3-5 kgf / cm 2 , and the hot pressing time is 5-30 min.

[0024] According to the application, preferably, the single piece mass of the nanoscale enzyme composite preparation effervescent tablet prepared is 0.3-0.5 g.

[0025] A nanoscale enzyme composite preparation effervescent tablet for rapid degradation of organic pollutants is prepared by using the above method.

[0026] The application of the nanometer enzyme composite preparation effervescent tablet prepared by the method is used for rapid degradation of organic pollutants in a liquid system, and the dosage is 0.3-0.5 g.

[0027] The application obtains the MnO2@Fe nanometer enzyme by the ratio of a specific iron salt and manganese sulfate monohydrate, the obtained MnO2@Fe nanometer enzyme is mixed and pressed into an effervescent tablet with sodium percarbonate, the sodium percarbonate can be efficiently activated, a Fenton system is formed by activating the sodium percarbonate with the catalyst to promote the degradation of pollutants, and the pollutants in industrial wastewater are treated by using the method of advanced oxidation.

[0028] The application combines the activation of the sodium percarbonate with the MnO2@Fe nanometer enzyme catalyst and the preparation of the effervescent tablet, utilizes the principle of the effervescent tablet, and is settled in water to generate a large number of small and dense bubbles to replace the stirrer, so that the reaction can be effectively promoted without a rotor, the catalyst can be maintained at the bottom of the reactor, and the catalyst is convenient to recycle.

[0029] Compared with the prior art, the application has the following advantages:

[0030] 1、The application obtains the MnO2@Fe nanometer enzyme by the ratio of a specific iron salt and manganese sulfate monohydrate, the obtained MnO2@Fe nanometer enzyme is mixed and pressed into an effervescent tablet with sodium percarbonate, the sodium percarbonate can be efficiently activated, a Fenton system is formed by activating the sodium percarbonate with the catalyst to promote the degradation of pollutants, and the pollutants in industrial wastewater are treated by using the method of advanced oxidation.

[0031] 2、The obtained nanometer enzyme composite preparation effervescent tablet can efficiently activate the sodium percarbonate after being put into water, the reaction is rapid, and the generation of active species and the degradation of pollutants are basically completed within 1-3 min.

[0032] 3、The manganese dioxide nanometer enzyme itself has certain oxidation degradation ability of organic pollutants, and the application obtains the MnO2@Fe nanometer enzyme by a specific ratio of iron salt and manganese sulfate monohydrate, and the obtained MnO2@Fe nanometer enzyme greatly enhances the ability of activating sodium percarbonate (SPC), and achieves the effect of more than the sum of its parts while activating percarbonate.

[0033] 4、The obtained nanometer enzyme composite preparation effervescent tablet avoids drug loss caused by multiple dosing, and since the effervescent tablet itself can produce a large number of small and dense bubbles, it can help the full mixing of the catalyst and percarbonate, and facilitates actual operation. BRIEF DESCRIPTION OF DRAWINGS

[0034] The drawings accompanying the specification of this application form a part thereof, serve to further provide a further understanding of the application, and together with the description of the exemplary embodiments of the application, serve to explain the application, and do not constitute an improper limitation of the application.

[0035] Figure 1 Mn 2p orbit XPS characterization of the MnO2@Fe nanometer enzyme (1 / 2) prepared in Example 1.

[0036] Figure 2 Fe 2p orbit XPS characterization of the MnO2@Fe nanometer enzyme (1 / 2) prepared in Example 1.

[0037] Figure 3 Full spectrum XPS characterization of the MnO2@Fe nanometer enzyme (1 / 2) prepared in Example 1.

[0038] Figure 4 Mn 2p orbit XPS characterization of the nano-MnO2 prepared in Comparative Example 1.

[0039] Figure 5 Full spectrum XPS characterization of the nano-MnO2 prepared in Comparative Example 1.

[0040] Figure 6 Effect diagram of the effervescent tablets prepared in Examples 1-6 and Comparative Example 1 on degradation of amoxicillin.

[0041] Figure 7 Effect diagram of the effervescent tablets prepared in Example 1 on degradation efficiency of amoxicillin at different pH values.

[0042] Figure 8 Effect diagram of the effervescent tablets prepared in Example 1 and the MnO2@Fe nanometer enzyme on degradation efficiency of different types of dyes.

[0043] Figure 9 Effect diagram of the effervescent tablets prepared in Examples 6, 12 and 13 on degradation of amoxicillin.

[0044] Figure 10 Figure showing the effect of effervescent tablets prepared for Examples 14, 15 on degradation of amoxicillin.

[0045] Figure 11 Figure showing the effect of effervescent tablets prepared for Examples 10, 11 on degradation of amoxicillin.

[0046] Figure 12 Figure showing the effect of effervescent tablets prepared for Examples 1, 8, 9 on degradation of amoxicillin.

[0047] Figure 13 Figure showing the effect of effervescent tablets prepared for Example 1 on degradation of amoxicillin at different concentrations. DETAILED DESCRIPTION

[0048] It should be noted that the following detailed description is illustrative only, and is intended to provide further description in order to provide a further understanding of the exemplary embodiments of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application pertains.

[0049] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It should be noted that the terms "comprises," "comprising," "includes," "including," and the like, when used in this specification, specify the presence of stated features, steps, operations, devices, components, and / or elements, but do not preclude the presence or addition of one or more other features, steps, operations, devices, components, and / or elements.

[0050] As mentioned in the background, the existing advanced oxidation process has the problems of difficult recovery of heterogeneous system materials and the need for multiple small amounts of chemicals. The present application prepares MnO2@Fe nanoscale enzyme by a specific ratio of iron salt and manganese sulfate monohydrate, which greatly enhances the ability to activate sodium percarbonate (SPC). In the specific implementation cases, several common pollutants in wastewater are selected, including antibiotics, herbicides, dyes, etc. The degradation capacity of the pollutants in different environments is explored to maximize the utilization efficiency of the catalyst and oxidant.

[0051] In order to enable those skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below in combination with specific examples and experimental examples.

[0052] The pollutants used in the examples are self-configured in the laboratory without the addition of other pollution components.

[0053] Example 1

[0054] The preparation method of the nanoscale enzyme composite preparation effervescent tablets is as follows:

[0055] 1) Respectively take 1.58 g KMnO4 and 2.53 g MnSO4·H2O samples and place them in a beaker, and respectively add 30 mL, 40 mL deionized water to dissolve, to obtain a potassium permanganate solution, a manganese sulfate monohydrate solution, add 1.265 g ferrous sulfate powder (mass ratio of ferrous sulfate: manganese sulfate monohydrate = 1 / 2) to the manganese sulfate monohydrate solution, drop the KMnO4 solution into the manganese sulfate monohydrate solution, stir thoroughly for 10 min, heat to 70℃, then slowly drop 10 mL of 10% nitric acid solution and start timing, continue stirring for 3 hours, then add 5 mL of 0.25 mol / L NaOH solution and continue stirring for 10 min, cool to room temperature, wash with deionized water and dry at 50℃ for 24 h, to obtain MnO2@Fe nanoscale enzyme.

[0056] The Mn 2p orbital XPS characterization, Fe 2p orbital XPS characterization and full spectrum XPS characterization of the obtained MnO2@Fe nanoscale enzyme are shown in Figures 1-3 It can be found that Fe is successfully doped into nano-MnO2 material, indicating that the MnO2@Fe (1 / 2) material is successfully prepared

[0057] 2) Mix the MnO2@Fe nanoscale enzyme obtained in step 1) and sodium percarbonate powder in a mass ratio of 3:1, and the amount of sodium percarbonate is such that the concentration in the activated system formed in the water body is 5 mM.

[0058] 3) Add the mixed powder obtained in step 2) to a 9-hole 10 mm mold, and place it in a hot press to form a hot press under a pressure of 3-5 kgf / cm 2 The temperature of the upper and lower electric heating plates is 15-25℃, the hot pressing time is 5-30 min, and the dry storage is obtained, to obtain MnO2@Fe effervescent tablets.

[0059] Example 2

[0060] The preparation method of the nanoscale enzyme composite preparation effervescent tablet is the same as described in Example 1, except that:

[0061] In step 1), 0.843 g of ferrous sulfate powder is added to the manganese sulfate monohydrate solution (ferrous sulfate: manganese sulfate monohydrate = 1 / 3), and the rest is performed according to Example 1.

[0062] Example 3

[0063] The preparation method of the nanoscale enzyme composite preparation effervescent tablet is the same as described in Example 1, except that:

[0064] In step 1), 0.506 g of ferrous sulfate powder is added to the manganese sulfate monohydrate solution (ferrous sulfate: manganese sulfate monohydrate = 1 / 5), and the rest is performed according to Example 1.

[0065] Example 4

[0066] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0067] In step 1), 0.421 g of ferrous sulfate powder (ferrous sulfate: manganese sulfate monohydrate = 1 / 6) is added to the manganese sulfate monohydrate solution, and the other steps are performed according to embodiment 1.

[0068] Embodiment 5

[0069] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0070] In step 1), 0.361 g of ferrous sulfate powder (ferrous sulfate: manganese sulfate monohydrate = 1 / 7) is added to the manganese sulfate monohydrate solution, and the other steps are performed according to embodiment 1.

[0071] Embodiment 6

[0072] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0073] In step 1), 1.265 g of ferrous chloride powder (ferrous chloride: manganese sulfate monohydrate = 1 / 2) is added to the manganese sulfate monohydrate solution, and the other steps are performed according to embodiment 1.

[0074] Embodiment 7

[0075] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0076] In step 1), 0.506 g of ferrous chloride powder (ferrous chloride: manganese sulfate monohydrate = 1 / 5) is added to the manganese sulfate monohydrate solution, and the other steps are performed according to embodiment 1.

[0077] Embodiment 8

[0078] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0079] In step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed in the water body is 1 mM, and the other steps are performed according to embodiment 1.

[0080] Embodiment 9

[0081] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0082] In step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed in the water body is 10 mM, and the other steps are performed according to embodiment 1.

[0083] Embodiment 10

[0084] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0085] In step 1), 0.506 g of ferrous sulfate powder is added to the manganese sulfate monohydrate solution (ferrous sulfate: manganese sulfate monohydrate = 1 / 5), and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed by being put into the water body is 1 mM, and the other steps are performed according to the embodiment 1.

[0086] Embodiment 11

[0087] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0088] In step 1), 0.506 g of ferrous sulfate powder is added to the manganese sulfate monohydrate solution (ferrous sulfate: manganese sulfate monohydrate = 1 / 5), and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed by being put into the water body is 5 mM, and the other steps are performed according to the embodiment 1.

[0089] Embodiment 12

[0090] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0091] In step 1), 1.265 g of ferrous chloride powder is added to the manganese sulfate monohydrate solution (ferrous chloride: manganese sulfate monohydrate = 1 / 2), and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed by being put into the water body is 1 mM, and the other steps are performed according to the embodiment 1.

[0092] Embodiment 13

[0093] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0094] In step 1), 1.265 g of ferrous chloride powder is added to the manganese sulfate monohydrate solution (ferrous chloride: manganese sulfate monohydrate = 1 / 2), and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed by being put into the water body is 10 mM, and the other steps are performed according to the embodiment 1.

[0095] Embodiment 14

[0096] The preparation method of the nano-enzyme complex preparation effervescent tablet according to the embodiment 1 is different in that:

[0097] In step 1), 0.506 g of ferrous chloride powder is added to the manganese sulfate monohydrate solution (ferrous chloride: manganese sulfate monohydrate = 1 / 5), and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed by being put into the water body is 1 mM, and the other steps are performed according to the embodiment 1.

[0098] Example 15

[0099] The preparation method of the nano-enzyme complex preparation effervescent tablet is the same as that described in Example 1, except that:

[0100] In step 1), 0.506 g of ferrous chloride powder (ferrous chloride: manganese sulfate monohydrate = 1 / 5) is added to a manganese sulfate monohydrate solution, and in step 2), the amount of sodium percarbonate is such that the concentration in the activated system formed in the water body is 5 mM, and the rest is performed according to Example 1.

[0101] Comparative Example 1

[0102] 1) Respectively, 1.58 g of KMnO4 and 2.53 g of MnSO4·H2O samples were placed in a beaker and dissolved in 30 mL and 40 mL of deionized water, respectively. Then, the KMnO4 solution was added dropwise into the MnSO4 solution and stirred for 10 min. After heating to 70℃, 10 mL of 10% nitric acid solution was slowly added and the timing started. After continuous stirring for 3 hours, 5 mL of 0.25 mol / L NaOH solution was added and stirred for 10 min. After cooling to room temperature, it was washed with deionized water and dried at 50℃ for 24 h to obtain nano-MnO2 enzyme;

[0103] The Mn 2p orbital XPS characterization and full spectrum XPS characterization of the obtained nano-MnO2 enzyme are shown in Figures 4-5 It can be seen that the characteristic peak of MnO2 appears, indicating that the nano-MnO2 material is successfully synthesized.

[0104] 2) The MnO2@Fe nano-enzyme obtained in step 1) and sodium percarbonate powder were mixed in a mass ratio of 3:1, and the amount of sodium percarbonate was such that the concentration in the activated system formed in the water body was 5 mM,

[0105] 3) The mixed powder obtained in step 2) was added to a 9-hole 10 mm mold and placed in a hot press to form a hot press under a pressure of 3-5 kgf / cm 2 The temperature of the upper and lower electric heating plates was 15-25℃, the hot pressing time was 5-30 min, and the dry storage was obtained. MnO2 effervescent tablets were obtained.

[0106] Test Example 1

[0107] Seven 100 ml solutions of amoxicillin with a concentration of 10 mg / L were prepared, and the effervescent tablets prepared in Examples 1-6 and Comparative Example 1 were added to the amoxicillin solutions. The effects of different nano-enzyme catalytic activation of sodium percarbonate on the degradation of amoxicillin are shown in Figure 6 The results are shown in Figure 6It can be seen that the ferrous sulfate is the iron source, and the mass ratio of ferrous sulfate to manganese sulfate monohydrate is 1 / 2. The activated percarbonate has the best effect, and the activated sodium percarbonate forms a Fenton system to promote the degradation of pollutants.

[0108] Test Example 2

[0109] Amoxicillin solutions with pH values of 3, 5, 7, 9, and 11 and a concentration of 10 mg / L were prepared.

[0110] The effervescent tablets prepared in Example 1 were placed in amoxicillin solutions with different pH values, and the effect of MnO2@Fe nanoscale enzyme catalytic activation of percarbonate on the degradation of amoxicillin at different pH values is shown in Figure 7 Figure 7 It can be seen that the activated percarbonate has similar effects at pH values of 3-9.

[0111] Test Example 3

[0112] Methylene blue, congo red, and rhodamine B dye solutions with a concentration of 10 mg / L were prepared,

[0113] The effervescent tablets prepared in Example 1 were placed in the three dye solutions,

[0114] The three selected dyes are cationic dye methylene blue, anionic dye congo red, and synthetic basic dye rhodamine B. The MnO2@Fe nanoscale enzyme prepared in Example 1 and the effervescent tablets prepared in Example 1 were added to the three dye solutions, and the effect of the effervescent tablets prepared in Example 1 on the degradation of different types of dyes is shown in Figure 8 The results show that, in the presence of only nanoscale enzyme, only methylene blue has a good degradation effect and is similar to the effect of the MnO2@Fe / SPC effervescent tablets of Example 1, and congo red and rhodamine B both show that the nanoscale enzyme itself can degrade the dyes, but the effect is poor. However, in the presence of MnO2@Fe / SPC effervescent tablets formed with percarbonate sodium, the degradation of dyes is significantly improved, with a 97% increase in congo red. In rhodamine B, the degradation efficiency can reach 100%, which is the best among all dyes, and the apparent rate constant value is also the largest.

[0115] Test Example 4

[0116] Amoxicillin solutions with a concentration of 10 mg / L were prepared, and the effervescent tablets prepared in Examples 6, 12, and 13 were placed in the amoxicillin solutions, and the effect of different nanoscale enzyme catalytic activation of percarbonate sodium on the degradation of amoxicillin is shown in Figure 9

[0117] Test Example 5

[0118] ​​The effeets of different nano-enzyme catalytic activation of sodium carbonate on degradation of amoxicillin are shown in Table 1. Figure 10

[0119] Comparison Figure 9 , Figure 10 It can be seen that the degradation effect of the effervescent tablets prepared by the mass ratio of ferrous chloride to manganese sulfate monohydrate 1 / 2 is higher than that of the effervescent tablets prepared by the mass ratio of ferrous chloride to manganese sulfate monohydrate 1 / 5. The effect of MnO2@Fe nano-enzyme is improved, and the degradation efficiency is improved by 30%. At the same time, the more the content of oxidant sodium carbonate, the better the degradation effect on amoxicillin. However, too much oxidant will increase the cost of drugs, and the degradation efficiency improvement is not great. Therefore, 5 mM is selected as the optimal concentration of sodium carbonate.

[0120] Test Example 6

[0121] The effeets of different nano-enzyme catalytic activation of sodium carbonate on degradation of amoxicillin are shown in Table 1. Figure 11

[0122] Test Example 7

[0123] The effeets of different nano-enzyme catalytic activation of sodium carbonate on degradation of amoxicillin are shown in Table 1. Figure 12

[0124] Comparison Figure 11 , Figure 12 It can be seen that the degradation effect of the effervescent tablets prepared by the mass ratio of ferrous chloride to manganese sulfate monohydrate 1 / 2 is higher than that of the effervescent tablets prepared by the mass ratio of ferrous chloride to manganese sulfate monohydrate 1 / 5. The effect of MnO2@Fe nano-enzyme is improved, and the degradation efficiency is improved by 30%. At the same time, the more the content of oxidant sodium carbonate, the better the degradation effect on amoxicillin. However, too much oxidant will increase the cost of drugs, and the degradation efficiency improvement is not great. Therefore, 5 mM is selected as the optimal concentration of sodium carbonate.

[0125] Test Example 8

[0126] Different concentrations of amoxicillin solutions were prepared, and the concentrations of amoxicillin were 4 mg / L, 8 mg / L, 16 mg / L, 20 mg / L, and 24 mg / L, each 100 ml.

[0127] ​​​The effervescence tablets prepared in Example 1 were put into amoxicillin solutions with different concentration gradients, and the effect of the catalytic activation of sodium carbonate by MnO2@Fe nanoscale enzyme on the degradation of amoxicillin with different concentrations was as shown in Figure 13 When the concentration of pollutants increased from 4 mg / L to 16 mg / L, there was a higher removal efficiency. In order to form a sharp contrast with other experiments, 10 mg / L, which had a better effect, was selected as the actual pollutant concentration for treatment. When the concentration of pollutants was more than 16 mg / L, it played an inhibitory role on the removal of amoxicillin. It was shown that the MnO2@Fe nanoscale enzyme had a good effect on the activation of sodium carbonate in low and medium concentration amoxicillin-containing wastewater.

[0128] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1.A method for preparing a nanoscale enzyme composite effervescent tablet for rapid degradation of organic pollutants, comprising the following steps: 1) adding a ferrous salt powder into a manganese sulfate monohydrate solution and stirring, then slowly adding a potassium permanganate solution drop by drop, stirring for 10-20 min, heating to 70℃ in an oil bath, slowly adding a nitric acid solution with a mass concentration of 8-12%, maintaining the temperature and stirring for 2-3 h, then adding a sodium hydroxide solution and stirring for 20-40 min, cooling to room temperature, repeatedly rinsing the obtained reaction product, drying, sieving, and obtaining a MnO2@Fe nanoscale enzyme; the ferrous salt powder is ferrous chloride powder or ferrous sulfate powder, and the mass ratio of the ferrous salt powder to the manganese sulfate monohydrate in the manganese sulfate monohydrate solution is 1:7-1:2; 2) mixing the MnO2@Fe nanoscale enzyme obtained in step 1) and sodium percarbonate powder; 3) adding the mixed powder obtained in step 2) into a mold and hot-pressing to form a nanoscale enzyme effervescent tablet. 2.The method according to claim 1, wherein in step 1), the concentration of the manganese sulfate monohydrate solution is 0.1-0.4 mmol / L, and the concentration of the potassium permanganate solution is 0.2-0.6 mmol / L. 3.The method according to claim 1, wherein in step 1), the volume ratio of the potassium permanganate solution to the manganese sulfate monohydrate solution is (1-4):(3-6). 4.The method according to claim 3, wherein in step 1), the volume ratio of the nitric acid solution to the manganese sulfate monohydrate solution is 1:(3-5), and the concentration of the sodium hydroxide solution is 0.1-0.3 mol / L; the volume ratio of the sodium hydroxide solution to the manganese sulfate monohydrate solution is 1:(7-9). 5.The method according to claim 1, wherein in step 1), the volume ratio of the potassium permanganate solution to the manganese sulfate monohydrate solution is (1-4):(3-6). 6.A nanoscale enzyme composite effervescent tablet for rapid degradation of organic pollutants, prepared by the method of any one of claims 1-5. 7.The nanoscale enzyme composite effervescent tablet prepared by the method of any one of claims 1-5, which is used for rapid degradation of organic pollutants in a liquid system, and the dosage is 0.3-0.5 g. ​ In step 2), the amount of sodium percarbonate is such that the concentration of sodium percarbonate in the activated system formed in the water body is 1-10 mM, in step 2), the mass ratio of MnO2@Fe nanoscale enzyme and sodium percarbonate powder mixed is (1-5):1, in step 3), hot pressing is carried out using a hot press, the temperature of the upper and lower platens of the hot press is 15-25℃, the pressure is 3-5kgf / cm 2 , and the hot pressing time is 5-30 min. ​ ​

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