A hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone and a preparation method and application thereof

Abstract

The application discloses a hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing and decomposing ozone and a preparation method and application thereof, and belongs to the technical field of catalytic decomposition of gaseous pollutants, environmental protection and inorganic materials. The preparation method of the hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing and decomposing ozone comprises the following steps: (1) a polymer protective agent solution is added dropwise into a potassium permanganate solution, stirring is conducted, a MnCl2 solution is added, continuous stirring is conducted, a hydrothermal reaction is conducted, a reaction solution is obtained, cooling is conducted, washing is conducted, and drying is conducted to obtain a precursor; and (2) the precursor is calcined at high temperature in an inert atmosphere, and cooling is conducted, so that the hydrophobic manganese-based meso-crystal (Meso-MnO@C) catalyst for efficiently catalyzing and decomposing ozone is obtained. The Meso-MnO@C catalyst has super strong hydrophobicity. The surface hydrophobicity of the catalyst is regulated by adding the polymer protective agent, so that the long-term operation of the catalytic system in a humid environment can be promoted.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of catalytic decomposition of gaseous pollutants, environmental protection and inorganic materials, and particularly relates to a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone and a preparation method and application thereof. BACKGROUND

[0002] Ozone (O3) in the troposphere is one of the main components of photochemical smog. Due to its high reactivity and strong oxidizing ability, long-term exposure to ozone can easily cause upper respiratory tract lesions and central nervous system damage, and even lead to pulmonary emphysema and pulmonary edema. The products produced by the chemical reaction of ozone with different organic substances in the indoor environment are more serious damage to human function. Not only ozone itself is harmful to human health, but also high concentration of near-ground ozone is toxic to plant growth. With the rapid economic growth, the problem of ozone pollution in China's urban groups is becoming increasingly prominent, and atmospheric ozone pollution events occur frequently. Therefore, it is of great value and application prospect to develop efficient ozone purification technology.

[0003] Catalytic decomposition technology has been proven to be one of the effective methods for decomposing ozone. Through the electron transfer of the catalyst, ozone is converted into non-toxic oxygen. Compared with other ozone removal technologies, this technology requires lower apparent activation energy and reaction temperature, and has the advantages of rapid reaction and low energy consumption. At present, ozone decomposition catalysts are mainly divided into transition metal oxides and noble metals. However, the high cost of noble metal catalysts and the low efficiency of transition metal oxides hinder the practical application of this technology. The key to the poor performance of transition metal oxides in decomposing ozone is the low utilization rate of active sites and the easy deactivation in humid environment. Surface interface regulation is the main means to improve the performance of the catalyst. There are various ways to regulate the properties of the surface interface. How to improve the utilization rate of active sites and the humidity resistance of the catalytic system by precisely constructing the surface interface?

[0004] In recent years, mesocrystal catalysts have shown unique advantages in various catalytic reactions and have attracted widespread attention. Mesocrystal is a short name for mesostructured crystal, which is a kind of polycrystal with highly ordered nanoparticle superstructure. Although mesocrystal is a polycrystal, its crystallographic properties exhibit single-crystal properties. Compared with traditional single-crystal and polycrystal materials, due to the size and anisotropic shape of the nanoparticles, mesocrystal has good mechanical properties, high specific surface area, electronic transport properties and abundant defect sites. By constructing mesocrystal catalysts for ozone catalysis, it is expected to improve the utilization rate of active sites of the catalytic system and promote the performance improvement of the catalytic system.

[0005] In addition, easy deactivation in humid environment is one of the bottleneck problems of ozone catalyst application. By regulating the surface hydrophobicity of the catalyst, it is expected to solve the key problem of easy deactivation in humid environment, so as to promote the long-term operation of the catalytic system in humid environment. SUMMARY

[0006] The primary object of the present application is to overcome the drawbacks and deficiencies of the prior art and provide a preparation method of a hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing decomposition of ozone.

[0007] Another object of the present application is to provide a hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing decomposition of ozone prepared by the above preparation method.

[0008] Still another object of the present application is to provide an application of the above hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing decomposition of ozone.

[0009] The objects of the present application are achieved by the following technical solutions.

[0010] A preparation method of a hydrophobic manganese-based meso-crystal catalyst for efficiently catalyzing decomposition of ozone, comprising the following steps:

[0011] (1) dropping a polymer protective agent solution into a potassium permanganate (KMnO4) solution, stirring, adding a MnCl2 solution, continuing to stir, hydrothermal reaction, cooling, washing, and drying to obtain a precursor;

[0012] (2) calcining the precursor at high temperature in an inert atmosphere, and cooling to obtain the hydrophobic manganese-based meso-crystal (Meso-MnO@C) catalyst for efficiently catalyzing decomposition of ozone.

[0013] In step (1), the polymer protective agent preferably includes at least one of polyvinyl alcohol (PVA), polyoxyethylene-polyoxypropylene-polyoxyethylene (Pluronic P123), and gum arabic.

[0014] In step (1), the polymer protective agent and potassium permanganate are preferably calculated at a molar ratio of 114-286:375; more preferably at a molar ratio of 114:375.

[0015] In step (1), the potassium permanganate and manganese chloride are preferably calculated at a molar ratio of 187.5-562.5:39.2-254.8; more preferably at a molar ratio of 375:196.

[0016] In step (1), the stirring time is preferably 20-40 min; more preferably 30 min.

[0017] In step (1), the continued stirring time is preferably 20-40 min; more preferably 30 min.

[0018] In step (1), the hydrothermal reaction conditions are preferably 100-200℃ for 10-100 min; more preferably 180℃ for 30 min.

[0019] In step (1), the temperature of the drying is preferably 50-70 DEG C; more preferably 60 DEG C.

[0020] In step (2), the inert atmosphere is preferably a nitrogen atmosphere.

[0021] In step (2), the high-temperature calcination is preferably 200-800 DEG C for 1-5 h; more preferably 500 DEG C for 2 h.

[0022] In step (2), the high-temperature calcination has a heating rate of preferably 3-7 DEG C / min; more preferably 5 DEG C / min.

[0023] A hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone is prepared by the above preparation method.

[0024] The hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone is used for removing ozone.

[0025] The concentration of the ozone is preferably 45-55 ppm, and the gas humidity is 15-90%; more preferably 50 ppm, and the relative humidity is 30-70%.

[0026] A method for removing ozone using a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone, comprising the step of immobilizing the hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone on a membrane to form a Meso-MnO@C catalytic membrane.

[0027] The membrane preferably comprises at least one of a polytetrafluoroethylene (PTFE) membrane, a polyether sulfone (PES) membrane, a polyvinylidene fluoride membrane (PVDF) membrane, and a carbon membrane; more preferably a polytetrafluoroethylene membrane.

[0028] The present application has the following advantages and effects relative to the prior art:

[0029] (1) The present application utilizes a polymer protective agent (at least one of polyvinyl alcohol PVA, polyoxyethylene-polyoxypropylene-polyoxyethylene (polyether P123) and gum arabic) to synthesize mesocrystal manganese oxide (i.e. a precursor) with abundant defect sites through a non-classical crystal growth process by a hydrothermal method, and then the precursor is calcined in a nitrogen atmosphere, so that the polymer protective agent is converted into a hydrophobic carbon layer, thereby obtaining a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone. The outer layer of the catalyst is coated with a hydrophobic carbon thin layer, and the inner layer is a micron-sized MnO mesocrystal composed of a large number of nanocrystals with uniform and ordered growth direction. The hydrophobic carbon thin layer is formed by pyrolysis of the polymer protective agent added in the precursor solution in an inert atmosphere (nitrogen). The present application aims to utilize the mesocrystal defect and manganese-based multiple variable valence of Meso-MnO@C and the hydrophobicity of the outer carbon layer to activate the surface carbon layer by capturing the electrons in the unsaturated Mn atoms inside, thereby driving the catalytic decomposition of ozone. The formed hydrophobic carbon layer inhibits the surface enrichment of water vapor, avoids the deactivation of the catalyst in a humid environment, and thus realizes efficient and stable catalytic decomposition of ozone. Under the conditions of 30% and 50% humidity of ozone gas, the removal rate of ozone by the Meso-MnO@C catalyst is 100% and 97%, respectively, which is greatly improved compared with the MnO2 polycrystal synthesized without adding a polymer protective agent.

[0030] (2) The present application synthesizes a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone by one-step hydrothermal method, which requires fewer chemical reagents, only three raw materials: potassium permanganate, MnCl2 and a polymer protective agent; the preparation process is simple, only needs to add the above raw materials into a high-pressure reaction kettle, heat and then calcine at high temperature; it is economical and practical, and easy to industrialize.

[0031] (3) The hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone of the present application has abundant defect sites and high specific surface area, and shows high efficiency and stability in the catalytic decomposition of ozone. Compared with the MnO2 polycrystal synthesized without adding a polymer protective agent, the catalytic decomposition of ozone is greatly improved. Moreover, the hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone of the present application has super strong hydrophobicity. The present application regulates the surface hydrophobicity of the catalyst by adding a polymer protective agent, which can solve the key problem of easy deactivation in a humid environment, thereby promoting the long-term operation of the catalytic system in a humid environment. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 X-ray diffraction patterns of the Meso-MnO@C catalyst prepared in Example 1 and MnO2 polycrystal.

[0033] Figure 2 Raman spectra of the Meso-MnO@C catalyst and the Meso-MnO catalyst without carbon layer coating.

[0034] Figure 3 Scanning electron microscope and transmission electron microscope images of Meso-MnO@C catalyst and MnO2 polycrystal; wherein (a) is the scanning electron microscope image of Meso-MnO@C catalyst; (b) is the scanning electron microscope image of MnO2 polycrystal; (c) is the transmission electron microscope image of Meso-MnO@C catalyst; (d) is the transmission electron microscope image of MnO2 polycrystal.

[0035] Figure 4 Water contact angle images of Meso-MnO@C catalyst and Meso-MnO catalyst without carbon layer coating; wherein (a) is the water contact angle image of Meso-MnO@C catalyst; (b) is the water contact angle image of Meso-MnO catalyst without carbon layer coating.

[0036] Figure 5 Ozone removal rate results of Meso-MnO@C catalyst, MnO2 polycrystal and Meso-MnO catalyst without carbon layer coating.

[0037] Figure 6 Ozone removal efficiency results of Meso-MnO@C catalyst film under the conditions of gas humidity of 30%, 50% and 70%, MnO2 polycrystal film under the condition of gas humidity of 50% and Meso-MnO catalyst film without carbon layer coating under the condition of gas humidity of 50%. DETAILED DESCRIPTION

[0038] The application will be described in further detail below with reference to the embodiments and drawings, but the embodiments of the application are not limited thereto.

[0039] Example 1: Preparation of a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone

[0040] A method for preparing a hydrophobic manganese-based mesocrystal catalyst for efficient catalytic decomposition of ozone, comprising the following steps:

[0041] Dissolve 2 g of polyvinyl alcohol (PVA, average molecular weight 1750 g / mol) into 30 mL of deionized water to obtain a clear and transparent solution, to obtain a PVA solution.

[0042] Weigh 0.5925 g of potassium permanganate (KMnO4) and 0.2473 g of manganese chloride (MnCl2) and dissolve them in 30 mL of deionized water solution respectively, to obtain a KMnO4 solution and a MnCl2 solution.

[0043] The PVA solution is added dropwise into the KMn04 solution, stirred vigorously for 30 min, and then the MnCl2 solution is added and stirred for another 30 min to obtain a mixed solution. The mixed solution is transferred into a 100 mL reactor, and reacted at 180 °C for 30 min to obtain a reaction solution. After the reactor is cooled, the reaction solution is centrifuged twice with deionized water to obtain a centrifuged sample. The centrifuged sample is dried in an oven at 60 °C to obtain a precursor. Finally, the precursor is calcined at 500 °C for 2 h under a nitrogen atmosphere, with a heating rate of 5 °C / min, and naturally cooled to obtain a hydrophobic meso-manganese oxide catalyst (Meso-MnO@C) with a hexahedron shape, which can efficiently catalyze the decomposition of ozone.

[0044] Method for preparing MnO2 polycrystal:

[0045] 0.5925 g of potassium permanganate (KMn04) and 0.2473 g of manganese chloride (MnCl2) are weighed and dissolved in 30 mL of deionized water solution, respectively, to obtain a KMn04 solution and a MnCl2 solution.

[0046] The MnCl2 solution is added into the KMn04 solution and stirred for 30 min to obtain a mixed solution. The mixed solution is transferred into a 100 mL reactor, and reacted at 180 °C for 30 min to obtain a reaction solution. After the reactor is cooled, the reaction solution is centrifuged twice with deionized water to obtain a centrifuged sample. The centrifuged sample is dried in an oven at 60 °C to obtain a precursor. Finally, the precursor is calcined at 500 °C for 2 h under a nitrogen atmosphere, with a heating rate of 5 °C / min, and naturally cooled to obtain a MnO2 polycrystal.

[0047] Method for preparing Meso-MnO catalyst without carbon layer coating:

[0048] 2 g of polyvinyl alcohol (PVA, CAS number: 9002-89-5, average molecular weight 1750 g / mol) is dissolved in 30 mL of deionized water to obtain a clear and transparent PVA solution.

[0049] 0.5925 g of potassium permanganate (KMn04) and 0.2473 g of manganese chloride (MnCl2) are weighed and dissolved in 30 mL of deionized water solution, respectively, to obtain a KMn04 solution and a MnCl2 solution.

[0050] The PVA solution is added dropwise into the KMn04 solution, stirred vigorously for 30 min, and then the MnCl2 solution is added and stirred for another 30 min to obtain a mixed solution; the mixed solution is then transferred into a 100 mL reaction kettle, and reacted at 180°C for 30 min to obtain a reaction solution; after the reaction kettle is cooled, the reaction solution is washed twice by centrifugation with deionized water to obtain a centrifuged sample; the centrifuged sample is then dried in a 60°C oven to obtain a precursor; finally, the precursor is calcined at 500°C for 2 h under an air atmosphere, with a heating rate of 5°C / min, and after natural cooling, a Meso-MnO catalyst without carbon layer coating is obtained.

[0051] Example 2:

[0052] A method for preparing a hydrophobic manganese-based mesocrystal catalyst with high catalytic activity for ozone decomposition, comprising the following steps:

[0053] 2 g of polyether P123 (CAS No. 9003-960, purchased from Shanghai Maikelin Biochemical Technology Co., Ltd., relative molecular mass 164.1995) is dissolved in 30 mL of deionized water to obtain a clear and transparent solution, thereby obtaining a polyether P123 solution.

[0054] 0.5925 g of potassium permanganate (KMn04) and 0.2473 g of manganese chloride (MnCl2) are weighed and dissolved in 30 mL of deionized water, respectively, to obtain a KMn04 solution and a MnCl2 solution.

[0055] The polyether P123 solution is added dropwise into the KMn04 solution, stirred vigorously for 30 min, and then the MnCl2 solution is added and stirred for another 30 min to obtain a mixed solution; the mixed solution is then transferred into a 100 mL reaction kettle, and reacted at 180°C for 30 min to obtain a reaction solution; after the reaction kettle is cooled, the reaction solution is washed twice by centrifugation with deionized water to obtain a centrifuged sample; the centrifuged sample is then dried in a 60°C oven to obtain a precursor; finally, the precursor is calcined at 500°C for 2 h under an air atmosphere, with a heating rate of 5°C / min, and after natural cooling, a Meso-MnO catalyst without carbon layer coating is obtained.

[0056] Example 3:

[0057] 2 g of gum arabic (CAS: 9000-01-5, purchased from Shanghai Aradin Biochemical Technology Co., Ltd.) is dissolved in 30 mL of deionized water to obtain a clear and transparent solution, thereby obtaining a gum arabic solution.

[0058] 0.5925 g of potassium permanganate (KMn04) and 0.2473 g of manganese chloride (MnCl2) are weighed and dissolved in 30 mL of deionized water, respectively, to obtain a KMn04 solution and a MnCl2 solution.

[0059] The above-mentioned gum arabic solution was added dropwise to the KMnO4 solution, stirred vigorously for 30 minutes, and then MnCl2 solution was added and stirred for another 30 minutes to obtain a mixed solution; the mixed solution was then transferred to a 100-mL reactor and reacted at 180°C for 30 minutes to obtain a reaction solution; after the reactor was cooled, the reaction solution was centrifuged and washed twice with deionized water to obtain a centrifuged sample; the centrifuged sample was then placed in a 60°C oven to dry to obtain a precursor; finally, the precursor was calcined at 500°C for 2 hours under a nitrogen atmosphere with a heating rate of 5°C / min. After natural cooling, a hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst with hexahedral structure for efficient catalytic decomposition of ozone was obtained.

[0060] Performance Testing

[0061] X-ray diffractometer (XRD) was used to characterize the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst and MnO2 polycrystal prepared in Example 1 for efficient catalytic decomposition of ozone.

[0062] The X-ray diffraction results are as follows Figure 1 As shown. Figure 1 It can be seen that the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst for efficient catalytic decomposition of ozone prepared in Example 1 has good crystallinity, which is consistent with the MnO mesoscopic structure coated with a carbon layer.

[0063] Raman spectroscopy was used to characterize the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst and the carbon-free Meso-MnO catalyst prepared in Example 1 for efficient catalytic decomposition of ozone.

[0064] Figure 2 The Raman spectrum results show that the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst for efficient catalytic decomposition of ozone prepared in Example 1 contains a carbon layer and has a certain degree of graphitization, which is beneficial to electron transfer and avoids surface enrichment of water molecules.

[0065] Scanning electron microscopy and transmission electron microscopy were used to characterize the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst and MnO2 polycrystal prepared in Example 1 for efficient catalytic decomposition of ozone.

[0066] Figure 3 The results of scanning electron microscopy and transmission electron microscopy images show that compared with the irregular morphology of MnO2 polycrystals, the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst for efficient catalytic decomposition of ozone prepared in Example 1 has a regular morphology and a simple cubic structure.

[0067] The water contact angle measurement instrument was used to characterize the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst prepared in Example 1 and the Meso-MnO catalyst without carbon layer coating for catalytic decomposition of ozone.

[0068] The water contact angle diagram of the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst prepared in Example 1 and the Meso-MnO catalyst without carbon layer coating for catalytic decomposition of ozone. Figure 4 As shown in the results, the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst has strong hydrophobicity, while the Meso-MnO catalyst without carbon layer coating has hydrophilicity.

[0069] Example 1:

[0070] The activity of the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst, MnO2 polycrystal and Meso-MnO catalyst without carbon layer coating prepared in Example 1 for removing ozone (O3) was determined. The photocatalytic removal of O3 was carried out using a continuous flow catalytic reaction device: a table type ozone generator (purchased from Guangzhou Chuanghuan Ozone Electrical Equipment Co., Ltd., model: CH-ZTW3G).

[0071] Preparation of the hydrophobic manganese-based mesoscopic crystal catalyst film: 80 mg of the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst prepared in Example 1 was ultrasonically dispersed in 3 mL of anhydrous ethanol to obtain a Meso-MnO@C catalyst solution. Then, 1 mL of the Meso-MnO@C catalyst solution was dropped on each of three pieces of polytetrafluoroethylene (PTFE) film with a diameter of 47 mm, and was placed in a 60°C oven for drying for 3-5 min to obtain a Meso-MnO@C catalyst film immobilized on the film.

[0072] The method for immobilizing the MnO2 polycrystal and the Meso-MnO catalyst without carbon layer coating on the polytetrafluoroethylene (PTFE) film was the same as that for the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst, to obtain a MnO2 polycrystal film immobilized on the film and a Meso-MnO catalyst film without carbon layer coating immobilized on the film, respectively.

[0073] The Meso-MnO@C catalyst film was fixed in a closed fixed bed reactor, and an O3 gas stream containing 50 ppm was passed through the reactor, with a gas flow rate V 流 = 1000 mL / min and a gas humidity of 30%. The concentrations at the inlet and outlet of the reactor were monitored online by an O3 detector, and the O3 removal rate was calculated.

[0074] The calculation method for the O3 removal rate was:

[0075] O3 removal rate (%) = (initial O3 addition amount - O3 amount in tail gas) / initial O3 addition amount × 100%.

[0076] The results are as follows Figure 5 As shown in the figure, after 2 h of reaction, the Meso-MnO@C catalytic membrane was -1 ·g -1 When (V 空速 =V 流速 / m; where V 流 =1000mL / min, where m represents the mass of the highly efficient ozone decomposition hydrophobic manganese-based mesoscopic crystals (Meso-MnO@C) catalyst (m = 80mg). The O3 removal efficiency was 100%. Under the same conditions, the ozone removal efficiencies of a MnO2 polycrystalline membrane and a carbon-free Meso-MnO catalyst membrane were 60% and 45%, respectively. These results demonstrate that the Meso-MnO@C catalytic membrane exhibits excellent and stable O3 decomposition performance.

[0077] Application Example 2:

[0078] The experiment of removing ozone at different humidity using the hydrophobic manganese-based mesoscopic crystal (Meso-MnO@C) catalyst for efficient catalytic decomposition of ozone prepared in Example 1 was carried out using a closed fixed-bed reactor.

[0079] The preparation methods of the Meso-MnO@C catalytic film, the MnO2 polycrystalline film, and the Meso-MnO catalyst film without a carbon layer are as described in Application Example 1. The humidity stability of the Meso-MnO@C catalytic film was tested for 2.5 hours at gas (ozone) humidity levels of 30%, 50%, and 70%, respectively. The humidity stability of the MnO2 polycrystalline film and the Meso-MnO catalyst film without a carbon layer was also tested for 2.5 hours at a gas humidity of 50%.

[0080] The results are as follows Figure 6 As shown in the figure, after 2.5 hours, the ozone removal efficiency of the Meso-MnO@C catalytic membrane remained at 100%, 97%, and 95% under gas humidity of 30%, 50%, and 70%, respectively. The results show that the Meso-MnO@C catalytic membrane has excellent humidity stability. In contrast, the MnO2 polycrystalline membrane and the Meso-MnO catalyst membrane without a carbon layer coated with a carbon layer achieved catalytic ozone removal efficiencies of 62% and 57%, respectively, under gas humidity of 50%. Therefore, compared with the MnO2 polycrystalline and Meso-MnO catalysts without a carbon layer coated with a carbon layer, the Meso-MnO@C catalyst has superior catalytic performance for ozone removal under different humidity conditions.

[0081] The above embodiments are the preferred embodiments of the present application, but the embodiments of the present application are not limited to the above embodiments, and any changes, modifications, substitutions, combinations, simplifications, etc. made without departing from the spirit and principles of the present application should be equivalent replacement manners and should be included in the protection scope of the present application.

Claims

1. A method for preparing a hydrophobic manganese-based mesoscopic crystal catalyst for catalytic decomposition of ozone, characterized in that: The steps include: (1) Add the polymer protective agent solution dropwise to the potassium permanganate solution, stir, add the MnCl2 solution, continue stirring, hydrothermally react to obtain a reaction solution, cool, wash, and dry to obtain a precursor; (2) The precursor is calcined at high temperature in an inert atmosphere and cooled to obtain a hydrophobic manganese-based mesoscopic crystal Meso-MnO@C catalyst for catalytic decomposition of ozone; In step (1), the polymer protective agent includes at least one of polypropylene alcohol, polyoxyethylene-polyoxypropylene-polyoxyethylene and gum arabic.

2. The preparation method according to claim 1, characterized in that In step (2), the inert atmosphere is a nitrogen atmosphere.

3. The preparation method according to claim 1, characterized in that In step (1), the conditions of the hydrothermal reaction are: 100-200°C for 10-100 min; In step (2), the high-temperature calcination is calcination at 200-800° C. for 1-5 hours.

4. The preparation method according to claim 1, characterized in that In step (1), the polymer protective agent and potassium permanganate are calculated in a molar ratio of 114-286:375; In step (1), the potassium permanganate and manganese chloride are calculated in a molar ratio of 187.5-562.5:39.2-254.

8.

5. The preparation method according to claim 1, characterized in that In step (2), the heating rate of the high-temperature calcination is 3-7°C / min; In step (1), the drying temperature is 50-70°C; In step (1), the stirring time is 20 to 40 minutes; In step (1), the stirring time is 20 to 40 minutes.

6. A hydrophobic manganese-based mesoscopic crystal catalyst for catalytic decomposition of ozone, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 5.

7. Use of the hydrophobic manganese-based mesoscopic crystal catalyst for catalytically decomposing ozone according to claim 6 in removing ozone.

8. The use according to claim 7, characterized in that The ozone concentration is 45-55 ppm, and the gas humidity is 15%-90%.

9. A method for removing ozone using a hydrophobic manganese-based mesoscopic crystal catalyst for catalytic decomposition of ozone, characterized in that: The method comprises the steps of immobilizing the hydrophobic manganese-based mesoscopic crystal catalyst for catalytically decomposing ozone according to claim 6 on a membrane to prepare a Meso-MnO@C catalytic membrane.

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