Polymer microspheres and ammonia nitrogen remover, and preparation method and use thereof

Abstract

The present invention provides a polymer microsphere and an ammonia nitrogen remover, as well as a preparation method and uses thereof. The polymer microsphere is prepared by a suspension polymerization method. During the preparation process of the microsphere, an acrylate or methacrylate monomer containing EO and aryl is introduced to participate in a free radical polymerization reaction, thereby increasing the electron cloud density on the benzene ring, facilitating the introduction of more -SO3H during the sulfonation process, thereby improving the hydrophilicity of the polymer microsphere, increasing the wrinkles on the surface of the microsphere, further increasing the specific surface area of the polymer microsphere and the adsorption capacity for ammonia nitrogen compounds.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental pollution control, and particularly to a polymer microsphere and a preparation method thereof, an ammonia nitrogen remover and a preparation method and use thereof. Background Art

[0002] Ammonia-containing wastewater is a major component of domestic sewage, coking wastewater, and printing and dyeing wastewater, and is characterized by a large volume of water and complex types of pollutants. The high ammonia nitrogen content in ammonia-containing wastewater is due to the presence of inorganic nitrogen and organic nitrogen in the wastewater, where the inorganic nitrogen is present as NH3 and NH4 + , and the organic nitrogen is mainly urea, pyridine, and quinoline, etc. If ammonia nitrogen wastewater enters natural water bodies without treatment, it will cause the ammonia nitrogen content in the water bodies to exceed the standard, thus seriously endangering human production and life. The harms of excessive ammonia nitrogen concentration in water bodies include causing eutrophication of water bodies, the high-concentration ammonia nitrogen substances themselves having biological toxicity and directly harming aquatic organisms, and the nitrification reaction of ammonia nitrogen under the action of microorganisms producing nitrite with strong toxicity, which poses a direct threat to human health. Therefore, it is urgent to develop new technologies for the effective treatment of high-concentration ammonia nitrogen wastewater.

[0003] Regarding the treatment of ammonia nitrogen wastewater, the currently relatively mature technologies mainly include the following:

[0004] (1) Ammonia stripping technology: With the help of a stripping tower or an aeration tank, the free ammonia in the wastewater is converted into gaseous ammonia and carried away by air or other gases. However, this technology has strict requirements for process equipment, requires a large amount of energy for aeration and heating, cannot achieve complete removal of ammonia nitrogen, and will cause secondary pollution, such as ammonia gas being discharged into the atmosphere.

[0005] (2) Breakpoint chlorination method: Using a strong chlorine-containing oxidant to oxidize ammonia nitrogen in the wastewater into nitrogen gas or nitrate, the ammonia nitrogen removal rate is relatively high, but it will cause secondary pollution of the water body due to excessive residual chlorine and hypochlorite, etc., resulting in a large number of deaths of organisms such as fish in the water body.

[0006] (3) Chemical precipitation method: Among them, the common MAP method removes ammonia nitrogen by adding magnesium salts and phosphates to form magnesium ammonium phosphate precipitate, which is suitable for eutrophic wastewater, and the generated magnesium ammonium phosphate can also be used as a slow-release fertilizer. However, this method has not been applied on a large scale at present and only stays in the laboratory stage, and will cause too high total phosphorus content.

[0007] In view of the above-mentioned limitations of the existing ammonia nitrogen wastewater treatment methods, it is particularly necessary to develop a technology that can effectively remove ammonia nitrogen in wastewater without causing secondary pollution harmful to the environment. Summary of the Invention

[0008] In view of the disadvantages of the above-mentioned prior art, the object of the present invention is to provide a polymer microsphere, which can be used as an ammonia nitrogen remover to adsorb ammonia nitrogen impurities in water, thereby reducing the concentration of NH3-N, having a higher adsorption capacity and regeneration rate, and being used to solve the problems in the prior art.

[0009] To achieve the above object, the present invention is obtained through the following technical solutions.

[0010] In the first aspect, a polymer microsphere includes: obtained by suspension polymerization and sulfonation using a monofunctional monomer and a difunctional monomer, wherein the monofunctional monomer is selected from: styrene monomers and acrylate esters containing EO and aryl, styrene monomers and methacrylate esters containing EO and aryl, wherein the aryl is directly connected to EO, and the aryl is an aromatic ring or a heteroaromatic ring composed of 3-30 carbon atoms. Preferably, the aryl is a benzene ring.

[0011] Among them, the styrene monomers are selected from one or more of styrene, methylstyrene, and ethylstyrene;

[0012] Among them, the difunctional monomer is selected from divinylbenzene, including one or more mixtures of o-divinylbenzene, m-divinylbenzene, or p-divinylbenzene.

[0013] Among them, the structural formulas of the styrene monomer and the acrylate ester containing EO and aryl, and the styrene monomer and the methacrylate ester containing EO and aryl are:

[0014] 、 、 or

[0015] Any one of them, where n is a positive integer greater than or equal to 1.

[0016] Preferably, the monofunctional monomer further includes a (meth)acrylate monomer containing a hydroxyl group or an epoxy group.

[0017] Preferably, the monofunctional monomer further includes one or more of methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate.

[0018] Preferably, the acrylate ester or methacrylate ester containing EO and aryl is selected from: ethylene glycol phenyl ether acrylate (PHEA) or polyethylene glycol o-phenylphenyl ether acrylate (OPPEA).

[0019] In the second aspect, the preparation method of the above-mentioned polymer microsphere includes: suspension polymerization and sulfonation;

[0020] Among them, suspension polymerization includes dissolving a stabilizer in a solvent, dropping an initiator and a polymerizable monomer into the solvent containing the stabilizer for polymerization reaction, and controlling the temperature of the polymerization reaction to be 75-85 °C.

[0021] Among them, the stabilizer is selected from polyvinylpyrrolidone, and the solvent is selected from any one or more of ethanol, ethyl acetate, isopropanol or n-butanol; the initiator is selected from any one or more of azobisisoheptonitrile (ABVN), azobisisopentanenitrile (AMBN), azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO) or lauroyl peroxide (LPO); the polymerizable monomer molecule includes at least one unsaturated double bond, and is divided into monofunctional monomers and difunctional monomers according to the number of unsaturated double bonds.

[0022] Among them, the suspension polymerization product is obtained through centrifugation, suction filtration and drying.

[0023] Preferably, the drying method includes: baking drying, vacuum drying or spray drying.

[0024] Preferably, the vacuum drying is carried out at room temperature to 50 °C.

[0025] Among them, sulfonation includes adding the suspension polymerization product into concentrated sulfuric acid for sulfonation reaction.

[0026] Preferably, sulfonation also includes adding P2O to the mixture of concentrated sulfuric acid and the suspension polymerization product 5。

[0027] Preferably, the sulfonation reaction is carried out at 30-60 °C.

[0028] Preferably, after adding the suspension polymerization product into concentrated sulfuric acid, use ultrasound to disperse it evenly.

[0029] Among them, the sulfonation product is obtained through centrifugation, suction filtration and drying.

[0030] Preferably, the drying method includes: baking drying, vacuum drying or spray drying.

[0031] Preferably, the vacuum drying is carried out at room temperature to 50 °C.

[0032] In the third aspect, an ammonia nitrogen remover includes: the polymer microspheres described above.

[0033] In the fourth aspect, an ammonia nitrogen remover includes: the polymer microspheres described above and aluminum sol.

[0034] In the fifth aspect, a preparation method of the ammonia nitrogen remover described above includes: dispersing the polymer microspheres in aluminum sol, and after drying and evaporating the water in the aluminum sol, obtaining the ammonia nitrogen remover.

[0035] Among them, the drying methods include: baking drying, vacuum drying or spray drying.

[0036] Preferably, ultrasonic waves are used to disperse polymer microspheres in aluminum sol, and the ultrasonic time is 15 - 60 min.

[0037] Preferably, baking drying is carried out at a temperature of 100 - 150 °C.

[0038] In a sixth aspect, a use is provided, where the above-mentioned polymer microspheres are used to remove ammonia nitrogen compounds in water bodies.

[0039] The present invention has the following beneficial effects:

[0040] During the preparation process of polymer microspheres, acrylate or methacrylate monomers containing EO and aryl are introduced to participate in the free radical polymerization reaction. Among them, the O atom is connected to the aryl, and the conjugation effect is greater than the inductive effect. As a result, the O atom directly connected to the benzene ring shows an electron-donating property to the aryl, increasing the electron cloud density on the aryl. Especially, the electron cloud density at the ortho-position (C2, C6) and para-position (C4) of the O atom increases more. When sulfonation is carried out subsequently, electrophilic substitution reactions are more likely to occur, and -SO3H is grafted at the ortho-position and para-position of the oxygen atom, resulting in an enhanced ability for ion exchange with ammonia nitrogen compounds and a significant increase in the total adsorption amount. At the same time, introducing an EO chain segment into the polymerizable monomer helps to improve the hydrophilicity of the microspheres, increase the wrinkles on the surface of the microspheres, thereby increasing the specific surface area of the microspheres and the adsorption ability for ammonia nitrogen compounds. Description of the Drawings

[0041] Figure 1 The infrared spectrogram of sulfonated P(OPPEA-HEMA-St-DVP) microspheres and P(OPPEA-HEMA-St-DVP) microspheres prepared in Example 7, where (1) is P(OPPEA-HEMA-St-DVP) microspheres; (2) is sulfonated P(OPPEA-HEMA-St-DVP) microspheres.

[0042] Figure 2 The SEM images of the polymer microspheres prepared in Example 1, 3 and Comparative Example 1. Detailed Embodiments

[0043] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0044] Before further describing the specific embodiments of the present invention, it should be understood that the protection scope of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the embodiments of the present invention are for describing specific embodiments and not for limiting the protection scope of the present invention. The test methods without specific conditions noted in the following examples are generally carried out under conventional conditions or according to the conditions recommended by each manufacturer.

[0045] When the embodiments give a numerical range, it should be understood that unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art of this technology. In addition to the specific methods, equipment, and materials used in the embodiments, according to the knowledge of those skilled in the art of this technology and the description of the present invention, any methods, equipment, and materials similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to implement the present invention.

[0046] Example 1:

[0047] Using ethylene glycol phenyl ether acrylate (PHEA), glycidyl methacrylate (GMA), styrene (St), and divinylbenzene (DVP) as polymerizable monomers, polyvinylpyrrolidone (PVP-K30) as a stabilizer, azobisisobutyronitrile (AIBN) as an initiator, and ethanol as a solvent, P(PHEA-GMA-St-DVP) microspheres were prepared by dispersion polymerization.

[0048] Free radical polymerization reaction: Add 250 mL of a 0.6 wt% PVP ethanol solution to a flask, heat it to 78 °C, and mechanically stir for 15 minutes. Then, add 10 mL of DVP monomer, 5 mL of PHEA monomer, 5 mL of GMA monomer, and 40 mL of St monomer containing the initiator AIBN to the above solution. The amount of AIBN is 1 wt% of the total weight of the monomers. Control the temperature within the range of 77 - 83 °C for the polymerization reaction. After reacting for 12 hours, the crude product is obtained by centrifugation, and the crude product is washed with an ethanol / water mixed solution and filtered by suction. Then, the solid particles obtained by suction filtration are dried under vacuum at room temperature to obtain P(PHEA-GMA-St-DVP) microspheres.

[0049] Sulfonation reaction: 15 g of dry P(PHEA-GMA-St-DVP) microspheres and 250 mL of concentrated sulfuric acid were added to a flask, and then ultrasonically dispersed to form a uniform suspension. Then, 0.5 g of P2O5 was added to the above suspension. The sulfonation reaction was carried out in a water bath at 40 ± 1 °C, with mechanical stirring for 10 hours. After the reaction was completed, the suspension was slowly added to 200 mL of deionized water, and then the crude product was separated by centrifugation. The crude product was washed with deionized water and filtered by suction. Then, the solid particles obtained by suction filtration were soaked in 5wt% sulfuric acid for 8 h to form microspheres with H + groups for subsequent ion exchange. After soaking, the microspheres were washed with water until the pH reached 7, and the product was vacuum dried at 40 °C to obtain sulfonated P(PHEA-GMA-St-DVP) microspheres.

[0050] Example 2

[0051] Under ultrasonic assistance, 5 g of the sulfonated P(PHEA-GMA-St-DVP) microspheres prepared in Example 1 were dispersed in 50 mL of nano-aluminum sol BRD-300B (Suzhou Baird New Materials) with a solid content of 20%. The ultrasonic dispersion time was 30 minutes. After high-temperature baking at 125 °C for 3 hours to remove the water vapor in the aluminum sol, aluminum hybridized sulfonated P(PHEA-GMA-St-DVP) microspheres were obtained.

[0052] Example 3

[0053] The preparation method was the same as that in Example 1, except that 10 mL of DVP monomer, 10 mL of PHEA monomer, and 40 mL of St monomer containing initiator AIBN were used as the monomers participating in the free radical polymerization reaction.

[0054] Example 4

[0055] Under ultrasonic assistance, 5 g of the sulfonated P(PHEA-St-DVP) microspheres prepared in Example 3 were dispersed in 50 mL of nano-aluminum sol BRD-300B (Suzhou Baird New Materials) with a solid content of 20%. The ultrasonic dispersion time was 30 minutes. After high-temperature baking at 125 °C for 3 hours to remove the water vapor in the aluminum sol, aluminum hybridized sulfonated P(PHEA-St-DVP) microspheres were obtained.

[0056] Example 5

[0057] Using poly(ethylene glycol o-phenylphenyl ether acrylate) (OPPEA), styrene (St), and divinylbenzene (DVP) as polymerizable monomers, polyvinylpyrrolidone (PVP-K30) as a stabilizer, azobisisobutyronitrile (AIBN) as an initiator, and ethanol as a solvent, P(OPPEA-St-DVP) microspheres were prepared by dispersion polymerization.

[0058] Free radical polymerization reaction: 250 mL of 0.6 wt% PVP ethanol solution was added to a flask, and the temperature was raised to 78 °C while mechanically stirring for 15 minutes. Then, 10 mL of DVP, 5 mL of OPPEA, and 45 mL of St monomer containing the initiator AIBN were dropped into the above solution. Among them, the dosage of AIBN was 1 wt% of the total weight of the monomers. The polymerization reaction was carried out within the temperature range of 77 - 83 °C. After 12 hours of reaction, the crude product was obtained by centrifugation, and the crude product was washed with an ethanol / water mixed solution and then filtered by suction. Then, the solid particles obtained by suction filtration were vacuum dried at room temperature, and thus P(OPPEA-St-DVP) microspheres were obtained.

[0059] Sulfonation reaction: 15 g of dried P(OPPEA-St-DVP) microspheres and 250 mL of concentrated sulfuric acid were added to a flask, and then ultrasonically dispersed to form a uniform suspension. Then, 0.5 g of P2O5 was added to the above suspension. The sulfonation reaction was carried out in a water bath at 40 ± 1 °C, and mechanical stirring was maintained for 10 hours. After the reaction was completed, the suspension was slowly added to 200 mL of deionized water, and then the crude product was separated by centrifugation, washed with deionized water and filtered by suction. Then, the solid particles obtained by suction filtration were soaked in 5 wt% sulfuric acid for 8 h to form groups with H + groups for subsequent ion exchange. After soaking, the microspheres were washed with clean water until the pH = 7, and the product was vacuum dried at 40 °C, and thus sulfonated P(OPPEA-St-DVP) microspheres were obtained.

[0060] Example 6

[0061] Under the ultrasonic assistance, 5 g of the sulfonated P(OPPEA-St-DVP) microspheres prepared in Example 5 were dispersed in 50 mL of nano-aluminum sol BRD-300B (Suzhou Baird New Materials) with a solid content of 20%. The ultrasonic dispersion time was 30 minutes. After high-temperature baking at 125 °C for 3 hours, the water in the aluminum sol was removed, and aluminum hybridized sulfonated P(OPPEA-St-DVP) microspheres were obtained.

[0062] Example 7

[0063] The preparation method was the same as that of Example 5, except that the monomers participating in the free radical polymerization reaction used 10 mL of DVP monomer, 5 mL of OPPEA monomer, 5 mL of 2-hydroxyethyl methacrylate (HEMA) monomer, and 40 mL of St monomer containing the initiator AIBN, and thus sulfonated P(OPPEA-HEMA-St-DVP) microspheres were obtained.

[0064] Example 8

[0065] Under ultrasonic assistance, 5 g of the sulfonated P(OPPEA-HEMA-St-DVP) microspheres prepared in Example 7 were dispersed in 50 mL of nano-aluminum sol BRD-300B (Suzhou Baird New Materials) with a solid content of 20%. The ultrasonic dispersion time was 30 minutes. After high-temperature baking at 125 °C for 3 hours, the water in the aluminum sol was removed to obtain aluminum hybrid sulfonated P(OPPEA-HEMA-St-DVP) microspheres.

[0066] Comparative Example 1

[0067] Using styrene (St) and divinylbenzene (DVP) as polymerizable monomers, polyvinylpyrrolidone (PVP-K30) as a stabilizer, and azobisisobutyronitrile (AIBN) as an initiator, and ethanol as a solvent, P(St-DVP) microspheres were prepared by dispersion polymerization.

[0068] Free radical polymerization reaction: 250 mL of a 0.6 wt% PVP ethanol solution was added to a flask and heated to 78 °C. At the same time, mechanical stirring was carried out for 15 minutes. Then, 10 mL of DVP and 50 mL of the St monomer containing the initiator AIBN were added dropwise to the above solution. The amount of AIBN used was 1 wt% of the total weight of the monomers. The polymerization reaction was carried out within the temperature range of 77 - 83 °C. After 12 hours of reaction, the crude product was obtained by centrifugal separation, and the crude product was washed with an ethanol / water mixed solution and then subjected to suction filtration. The solid particles obtained by suction filtration were vacuum dried at room temperature to obtain P(St-DVP) microspheres.

[0069] Sulfonation reaction: 15 g of dried P(St-DVP) microspheres and 250 mL of concentrated sulfuric acid were added to a flask, and then ultrasonic dispersion was carried out to form a uniform suspension. Then, 0.5 g of P2O5 was added to the above suspension. The sulfonation reaction was carried out in a water bath at 40 ± 1 °C while maintaining mechanical stirring for 10 hours. After the reaction was completed, the suspension was slowly added to 200 mL of deionized water, and then the crude product was separated by centrifugation, washed with deionized water and subjected to suction filtration. The solid particles obtained by suction filtration were vacuum dried at room temperature to obtain sulfonated P(St-DVP) microspheres.

[0070] Comparative Example 2

[0071] Under ultrasonic assistance, 5 g of the sulfonated P(St-DVP) microspheres prepared in Comparative Example 1 were dispersed in 50 mL of nano-aluminum sol BRD-300B (Suzhou Baird New Materials) with a solid content of 20%. The ultrasonic dispersion time was 30 minutes. After high-temperature baking at 125 °C for 3 hours, the water in the aluminum sol was removed to obtain aluminum hybrid sulfonated P(St-DVP) microspheres.

[0072] Structural characterization and surface observation of microspheres: Specifically, comparative tests were carried out on the P(OPPEA-HEMA-St-DVP) microspheres and sulfonated P(OPPEA-HEMA-St-DVP) microspheres prepared in Example 7 using Fourier transform infrared spectroscopy (FTIR). The surface morphologies of the microspheres prepared in Examples 1, 3 and Comparative Example 1 were observed using scanning electron microscopy (SEM). At the same time, the specific surface area and average diameter of the polymer microspheres prepared in Examples 1, 3, 5, 7 and Comparative Example 1 were tested using the BET specific surface area measurement method and a Malvern laser particle size analyzer.

[0073] Breakthrough adsorption capacity of ammonia nitrogen remover

[0074] The breakthrough adsorption capacity of the microspheres was calculated by multiplying the difference between the initial NH3-N concentration and the NH3-N concentration after adsorption by the volume of the sewage, and was used to evaluate the adsorption capacity of the microsphere material for ammonia nitrogen. The calculation formula is as follows:

[0075] ;

[0076] where Q is the breakthrough adsorption capacity, is the initial NH3-N concentration, is the NH3-N concentration after adsorption, and V is the volume of the sewage.

[0077] Regeneration rate of ammonia nitrogen remover:

[0078] The regeneration rate was used to represent the change in the adsorption capacity of the ammonia nitrogen remover after desorption. The calculation formula is as follows:

[0079] ;

[0080] where, is the regeneration rate of the ammonia nitrogen remover, is the NH3-N concentration after the first adsorption, is the NH3-N concentration after the second adsorption after desorption regeneration.

[0081] Determination of the breakthrough adsorption capacity of ammonia nitrogen remover: Weigh 5.0 g of the microspheres prepared in Examples 1-8 and Comparative Examples 1 and 2 into 250 mL conical flasks, and add 100 mL of ammonia nitrogen-containing printing and dyeing wastewater discharged by Taizhou Wannuo Textile Co., Ltd. The NH3-N concentration in the wastewater is 120 mg / L. Place the conical flasks in a water bath constant temperature shaker and stir at a speed of 100 r / min for 12 h at room temperature to make the adsorption reach equilibrium. After standing for 12 h, take the supernatant to measure the ammonia nitrogen concentration. The method for detecting the ammonia nitrogen concentration is spectrophotometry, and the ammonia nitrogen removal rate is calculated therefrom.

[0082] Determination of the regeneration rate of ammonia nitrogen remover: Accurately weigh 5 g of the saturated-adsorbed microspheres into a beaker. Then, add 15 mL of saturated NaCl solution, 15 mL of 5 wt% NaOH solution, and 15 mL of 5 wt% H2SO4 solution to the beaker in sequence to regenerate the saturated-adsorbed microspheres. Finally, add 25 mL of deionized water for rinsing. After soaking in clear water for 2 h, filter to remove the water. After the regeneration is completed, perform secondary adsorption under the same experimental conditions, measure the ammonia nitrogen concentration in the adsorbed effluent, and calculate the breakthrough adsorption capacity after regeneration and the regeneration rate of the ammonia nitrogen adsorbent.

[0083] The test results of the specific surface area, average diameter, ammonia nitrogen removal capacity, and regeneration rate of the polymer microspheres prepared in Examples 1-8 and Comparative Examples 1 and 2 are listed in Table 1.

[0084] Table 1

[0085]

[0086] Figure 1 The infrared spectra of P(OPPEA-HEMA-St-DVP) microspheres (1) and sulfonated P(OPPEA-HEMA-St-DVP) microspheres (2) are shown. The peak at 1600 cm -1 is attributed to the benzene ring vibration band, the peak at 1723 cm -1 is attributed to the stretching vibration of C=O, the peak at 1490 cm -1 is attributed to the stretching vibration of -C-O-, and the peak at 907 cm -1 is attributed to the epoxy group. For the sulfonated P(OPPEA-HEMA-St-DVP) microspheres (2), peaks at 1190 cm -1 and 1068 cm -1 are added on the basis of (1), indicating that the -SO3H group has been successfully introduced onto the microsphere surface. Figure 2 The surface morphologies of different microspheres are shown. In Examples 1 and 3, PHEA is added as a polymerizable monomer for the suspension polymerization of microspheres, and the prepared microspheres have more wrinkles on the surface. In Comparative Example 1, only styrene and divinylbenzene are used as polymerizable monomers, and the prepared microspheres are smoother and flatter on the surface, without obvious wrinkles.

[0087] Judging from the adsorption capacity and regeneration rate of the microspheres in Table 1 as ammonia nitrogen removers, the adsorption capacity of Examples 1-8 is significantly higher. The adsorption capacity can be further improved after hybridizing the polymer microspheres with aluminum sol, but the regeneration rate will decrease. The adsorption capacity of Comparative Examples 1 and 2 is significantly lower than that of Examples 1-8. The reason is that the sulfonated P(St-DVP) microspheres prepared in Comparative Example 1 were found to be too smooth on the surface through SEM observation, and their specific surface area measured by BET is significantly lower than that of the microspheres prepared in Examples 1-8. The contact area with ammonia nitrogen adsorbates in sewage is smaller, resulting in worse adsorption and removal effects on ammonia nitrogen adsorbates than the microspheres in Examples 1-8. In addition, the sulfonated P(St-DVP) microspheres prepared in Comparative Example 1 did not use monomers containing EO segments, had poor hydrophilicity, lacked the conjugation effect of oxygen atoms on the benzene ring to increase the electron cloud density on the benzene ring, and the subsequent sulfonation reaction was more difficult to carry out.

[0088] Based on Examples 1, 3, 5, 7 and Comparative Example 1, aluminum sol was added in Examples 2, 4, 6, 8 and Comparative Example 2 to introduce Al on the surface of the polymer microspheres 3+ , which is beneficial to the cation exchange with ammonia nitrogen adsorbates. However, after the exchange, Al 3+ is difficult to regenerate by conventional methods, resulting in a low regeneration rate of the ammonia nitrogen remover.

[0089] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of them. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. Although the specific implementation manners of the present invention have been described above, it is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications or deformations that can be made without creative labor on the basis of the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A polymer microsphere, characterized in that, It is obtained by suspension polymerization and sulfonation using a monofunctional monomer and a difunctional monomer; wherein, the monofunctional monomer is selected from: styrene monomers and acrylates containing EO and aryl, styrene monomers and methacrylates containing EO and aryl, wherein the aryl is directly connected to EO; The difunctional monomer is selected from divinylbenzene, and divinylbenzene includes one or more mixtures of o-divinylbenzene, m-divinylbenzene or p-divinylbenzene; The styrene monomer is selected from one or more of: styrene, methylstyrene and ethylstyrene; The structural formula of the acrylate containing EO and aryl is: or ; The structural formula of the methacrylate containing EO and aryl is: or ; Wherein n is a positive integer greater than or equal to 1.

2. The polymer microspheres according to claim 1, wherein The aryl is a benzene ring.

3. The polymer microspheres according to claim 1, characterized in that, The monofunctional monomer includes (meth)acrylate containing hydroxyl or epoxy group; And / or, the monofunctional monomer includes one or more of: methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, dodecyl (meth)acrylate and octadecyl (meth)acrylate.

4. The preparation method of the polymer microspheres according to any one of claims 1-3, characterized in that The preparation method includes: suspension polymerization and sulfonation; Suspension polymerization includes dissolving a stabilizer in a solvent, dropping an initiator and a polymerizable monomer into the solvent containing the stabilizer for polymerization reaction, and controlling the temperature of the polymerization reaction to be 75 - 85 °C; Sulfonation includes adding the suspension polymerization product into concentrated sulfuric acid for sulfonation reaction.

5. The preparation method according to claim 4, characterized in that, The stabilizer is selected from polyvinylpyrrolidone; And / or, the solvent is selected from any one or more of ethanol, ethyl acetate, isopropanol or n-butanol; And / or, the initiator is selected from any one or more of azodiisooctanenitrile, azodiisovaleronitrile, azodiisobutyronitrile, benzoyl peroxide and dilauroyl peroxide; And / or, the polymerizable monomer molecule includes at least one unsaturated double bond.

6. The preparation method according to claim 4, characterized in that, The suspension polymerization product is obtained through centrifugation, suction filtration and drying; and / or, sulfonation includes adding P2O to a mixture of concentrated sulfuric acid and the suspension polymerization product 5； And / or, the sulfonation reaction is carried out at 30 - 60 °C; And / or, after adding the suspension polymerization product into concentrated sulfuric acid, use ultrasound to disperse it evenly; And / or, the sulfonation product is obtained through centrifugation, suction filtration and drying.

7. An ammonia nitrogen remover, characterized in that, The ammonia nitrogen remover includes: the polymer microspheres described in any one of claims 1 - 3.

8. An ammonia nitrogen remover, characterized in that, The ammonia nitrogen remover includes: the polymer microspheres described in any one of claims 1 - 3 and aluminum sol.

9. The preparation method of the ammonia nitrogen remover according to claim 8, wherein, Disperse the polymer microspheres in aluminum sol, and obtain the ammonia nitrogen remover through drying; the drying method includes: baking drying, vacuum drying or spray drying.

10. A use, characterized in that, Use the polymer microspheres described in any one of claims 1 - 3 to remove ammonia nitrogen compounds in water.

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