Quaternary ammonium salt polymer catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of water treatment, in particular to a quaternary ammonium salt polymer catalyst and a preparation method and application thereof. The quaternary ammonium salt polymer catalyst provided by the invention is prepared by the following steps: generating water-in-oil liquid drops from a raw material mixed solution comprising a precursor material, water, a photoinitiator and a cross-linking agent through a microfluidic technology, polymerizing under ultraviolet irradiation, and then carrying out anion exchange, the precursor material is prepared by reacting raw materials including acrylate and halogenated alkane. The quaternary ammonium salt polymer catalyst provided by the invention can activate peroxide to generate intermediate active species of ketone peroxide so as to oxidize and degrade organic pollutants, and meanwhile, ketone peroxide further reacts to generate singlet oxygen, so that the degradation of the organic pollutants can be enhanced. The quaternary ammonium salt polymer catalyst provided by the invention has high catalytic efficiency, and can realize efficient removal of organic pollutants in a short time.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and in particular to a quaternary ammonium salt polymer catalyst, a preparation method thereof, and an application thereof. Background Art

[0002] Currently, methods for removing organic pollutants include adsorption, membrane filtration, advanced oxidation, etc. Among them, adsorption and membrane filtration are physical processes and do not completely remove phenolic compounds. In contrast, advanced oxidation is more attractive. Advanced oxidation processes based on peroxides such as PMS, PDS, and PAA can generate highly oxidizing free radicals (·OH, ·SO4 - etc.) and selective non-free radical species ( 1 O2, activated persulfate complexes, high-valent metal oxygen complexes, etc.) through different activation methods, and can effectively treat organic pollutant wastewater.

[0003] Common homogeneous activation methods of oxidants include energy input (such as light, heat, electricity, microwave, ultrasonic, etc.) excitation activation, that is, the peroxy bond in the peroxide is broken by energy; transition metal ion activation, that is, Co 2+ 、Mn 2+ 、Fe 2+ etc. are used to induce the activation of peroxides to generate reactive species; compound catalysis, that is, special functional groups such as carbonyl can promote the decomposition of peroxides into 1 O2. Due to mass transfer and mixing efficiency, homogeneous activation often has higher reaction activity, but it is difficult to separate and reuse, which will increase the cost of water treatment and greatly limit the application of homogeneous catalysts. In contrast, heterogeneous catalysts have the advantage of easy separation. In recent years, a large number of studies have also shown that due to the difference in mechanism, heterogeneous oxidation can achieve higher removal efficiency with less oxidant. Therefore, the heterogeneous catalytic oxidation technology that is environmentally friendly, simple, efficient, and low-cost has the potential to purify organic polluted wastewater.

[0004] Traditional heterogeneous solid catalysts such as carbon-based materials, metal oxides, metal complexes, etc. often need to be synthesized under relatively complex and harsh conditions, such as high-temperature calcination, which increases the production cost of the catalyst and has the disadvantages of poor cyclic application ability and harsh regeneration conditions. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a quaternary ammonium salt polymer catalyst, a preparation method thereof, and an application thereof. The quaternary ammonium salt polymer catalyst provided by the present invention has high catalytic efficiency and can achieve the efficient removal of organic pollutants in a short time.

[0006] The present invention provides a quaternary ammonium salt polymer catalyst, which is prepared by generating water-in-oil droplets from a raw material mixture including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidic technology, polymerizing under ultraviolet light irradiation, and then performing anion exchange;

[0007] The precursor material is prepared by reacting raw materials including an acrylate and a halogenated alkane.

[0008] Preferably, the acrylate includes one or more of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, and 3-(dimethylamino)ethyl acrylate; the halogenated alkane includes one or more of 1-bromoundecane, 1-bromododecane, 1-bromotetradecane, 1-bromohexadecane, 1-bromoeicosane, 1-chlorododecane, 1-chlorotetradecane, and 1-chlorohexadecane;

[0009] The molar ratio of the acrylate to the halogenated alkane is 1:1 to 10.

[0010] Preferably, the preparation method of the precursor material includes the following steps:

[0011] Mix the acrylate, the halogenated alkane, and an organic solvent, and then carry out a reaction to obtain the precursor material;

[0012] The organic solvent is selected from at least one of acetone, acetonitrile, and methanol;

[0013] After the reaction, it further includes: mixing the reaction solution with a low-polarity solvent, precipitating a white precipitate, and obtaining the precursor material after suction filtration and drying;

[0014] The low-polarity solvent is selected from one of n-hexane, ethyl acetate, and petroleum ether.

[0015] Preferably, the photoinitiator is selected from at least one of benzoin dimethyl ether, 4-chlorobenzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and methyl o-benzoylbenzoate;

[0016] The crosslinking agent is an ester crosslinking agent, specifically selected from one of 1,4-butanediol dimethacrylate, ethylene glycol dimethacrylate, hexanediol dimethacrylate, and trimethylolpropane trimethacrylate;

[0017] The mass ratio of the precursor material to water is 0.5 to 2:1;

[0018] The mass ratio of the precursor material, the photoinitiator, and the crosslinking agent is 0.5 to 2:0.01 to 0.05:0.01 to 0.05.

[0019] The present invention also provides a preparation method of the above-mentioned quaternary ammonium salt polymer catalyst, including the following steps:

[0020] A raw material mixture containing a precursor material, water, a photoinitiator, and a crosslinking agent is used to generate water-in-oil droplets through microfluidics technology. After polymerization under ultraviolet light irradiation, anion exchange is then carried out to obtain a quaternary ammonium salt polymer catalyst.

[0021] Preferably, a water-in-oil droplet is generated from a raw material mixture containing a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidics technology, which specifically includes:

[0022] After heating and mixing the precursor material and water, the photoinitiator and the crosslinking agent are added and mixed. Using microfluidics technology, the raw material mixture flows into a four-way valve, and a low-polarity oil phase simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel;

[0023] The temperature for heating and mixing is 40 - 80 °C;

[0024] The low-polarity oil phase includes at least one of methyl silicone oil, ethyl silicone oil, and methylphenyl silicone oil;

[0025] The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1 - 0.5:1.

[0026] Preferably, the temperature for polymerization under ultraviolet light irradiation is room temperature, the time is 1 - 8 min, and the wavelength is 200 - 400 nm;

[0027] The anion exchange includes:

[0028] The spheres obtained by polymerization are placed in a packed column, and phosphate solution is added for elution to achieve anion exchange;

[0029] The concentration of the phosphate solution is 90 - 110 mmol / L;

[0030] The time for elution is 46 - 50 h.

[0031] The present invention also provides an application of the above-mentioned quaternary ammonium salt polymer catalyst or the quaternary ammonium salt polymer catalyst prepared by the above-mentioned preparation method in degrading organic pollutants in water treatment.

[0032] The present invention also provides a method for treating organic pollutants in water, including the following steps:

[0033] Under the condition of aeration, the water body to be treated, the catalyst, and the peroxide are mixed for degradation and mineralization to obtain a treated water body;

[0034] The catalyst is the above-mentioned quaternary ammonium salt polymer catalyst or the quaternary ammonium salt polymer catalyst prepared by the above-mentioned preparation method.

[0035] Preferably, the organic pollutants in the water to be treated include at least one of p-cresol, p-chlorophenol, 2,4-dichlorophenol, p-bromophenol, bisphenol F, and phenol;

[0036] In the water to be treated, the concentration of organic pollutants is 10 - 200 μmol / L, and the pH value is 5 - 11;

[0037] The peroxide includes at least one of peracetic acid, sodium persulfate, potassium persulfate, ammonium persulfate, potassium monopersulfate, sodium monopersulfate, and ammonium monopersulfate;

[0038] In the mixed water body, the concentration of the catalyst is 0.05 - 1 g / L, and the concentration of the peroxide is 0.1 - 50 mmol / L;

[0039] The temperature for degradation and mineralization is 5 - 40 °C.

[0040] The present invention provides a quaternary ammonium salt polymer catalyst, which is prepared by generating water-in-oil droplets from a raw material mixture including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidic technology, polymerizing under ultraviolet light irradiation, and then performing anion exchange; the precursor material is prepared by reacting raw materials including acrylate and haloalkane. The quaternary ammonium salt polymer catalyst provided by the present invention can activate peroxide to generate peroxyketone intermediate active species, thereby oxidizing and degrading organic pollutants. At the same time, peroxyketone further reacts to generate singlet oxygen, which can enhance the degradation of organic pollutants. The quaternary ammonium salt polymer catalyst provided by the present invention has high catalytic efficiency and can achieve efficient removal of organic pollutants in a short time. At the same time, the synthesis steps of the quaternary ammonium salt polymer catalyst provided by the present invention are simple in operation, the raw materials are easy to obtain, the production is easy to scale up, and the matrix tolerance ability is strong. Description of the Drawings

[0041] Figure 1 It is a schematic flow diagram of the microfluidic technology of the present invention;

[0042] Figure 2 It is the nuclear magnetic resonance hydrogen spectrum of the precursor material prepared in Example 1 of the present invention;

[0043] Figure 3 It is the scanning electron micrograph of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention;

[0044] Figure 4 It is the X-ray energy spectrum of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention;

[0045] Figure 5 It is the effect diagram of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention adsorbing organic matter;

[0046] Figure 6Rate graph of the peroxide catalyzed by the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention;

[0047] Figure 7 Adsorption and catalytic performance of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention in actual water bodies. Detailed implementation manners

[0048] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] The present invention provides a quaternary ammonium salt polymer catalyst, which is prepared by generating water-in-oil droplets from a raw material mixture including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidics technology, polymerizing under ultraviolet light irradiation, and then performing anion exchange;

[0050] The precursor material is prepared by reacting raw materials including an acrylate and a haloalkane.

[0051] In some embodiments of the present invention, the acrylate is one or more of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, and 3-(dimethylamino)ethyl acrylate; preferably dimethylaminoethyl methacrylate and / or dimethylaminoethyl acrylate. The haloalkane is one or more of 1-bromoundecane, 1-bromododecane, 1-bromotetradecane, 1-bromohexadecane, 1-bromoeicosane, 1-chlorododecane, 1-chlorotetradecane, and 1-chlorohexadecane; preferably one or more of 1-bromoundecane, 1-bromododecane, 1-bromotetradecane, and 1-bromohexadecane. The molar ratio of the acrylate to the haloalkane is 1:1 to 10, such as 1:1.4.

[0052] In some embodiments of the present invention, the preparation method of the precursor material includes the following steps:

[0053] Mix the acrylate, haloalkane, and organic solvent, and then react to obtain the precursor material.

[0054] The mixing is stirring mixing. The mixing time is 25 to 35 min, such as 30 min.

[0055] The reaction temperature is 10 to 200 °C, such as 70 °C; the time is 1 to 48 h, such as 48 h. The reaction is carried out in an organic solvent. The organic solvent is selected from at least one of acetone, acetonitrile, and methanol. The present invention has no special limitation on the amount of the organic solvent used, as long as it can completely dissolve the acrylate and the haloalkane.

[0056] After the reaction, it further includes: mixing the reaction solution with a low-polarity solvent to precipitate a white precipitate, and obtaining a precursor material after suction filtration and drying. The low-polarity solvent is selected from one of n-hexane, ethyl acetate, and petroleum ether. The volume ratio of the low-polarity solvent to the reaction solution is 3 to 5:1, such as 4:1. The drying is vacuum drying at room temperature.

[0057] In some embodiments of the present invention, the photoinitiator is selected from at least one of benzoin dimethyl ether, 4-chlorobenzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and methyl o-benzoylbenzoate.

[0058] In some embodiments of the present invention, the crosslinking agent is an ester crosslinking agent, specifically selected from one of 1,4-butanediol dimethacrylate, ethylene glycol dimethacrylate, hexanediol dimethacrylate, and trimethylolpropane trimethacrylate.

[0059] In some embodiments of the present invention, the mass ratio of the precursor material to water is 0.5 to 2:1, such as 2:1, 1:1. The water is deionized water.

[0060] In some embodiments of the present invention, the mass ratio of the precursor material, photoinitiator, and crosslinking agent is 0.5 to 2:0.01 to 0.05:0.01 to 0.05, such as 0.5 to 1:0.01 to 0.05:0.01 to 0.05, specifically 0.6:0.03:0.03 (20:1:1), 0.75:0.03:0.03 (25:1:1).

[0061] The present invention also provides a method for preparing the quaternary ammonium salt polymer catalyst described above, including the following steps:

[0062] Mixing a raw material mixture including a precursor material, water, a photoinitiator, and a crosslinking agent to generate water-in-oil droplets by microfluidic technology, polymerizing under ultraviolet light irradiation, and then performing anion exchange to obtain a quaternary ammonium salt polymer catalyst.

[0063] In some embodiments of the present invention, generating water-in-oil droplets from a raw material mixture including a precursor material, water, a photoinitiator, and a crosslinking agent by microfluidic technology specifically includes:

[0064] After heating and mixing the precursor material and water, adding the photoinitiator and crosslinking agent and mixing them evenly, using microfluidic technology, the raw material mixture flows into a four-way valve, and a low-polarity oil phase simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. As Figure 1 shown. Figure 1 is a schematic flow diagram of the microfluidic technology of the present invention.

[0065] The temperature for heating and mixing is 40 - 80°C, such as 60°C.

[0066] The low-polarity oil phase is selected from at least one of methyl silicone oil, ethyl silicone oil, and methylphenyl silicone oil.

[0067] In the present invention, the raw material mixture flows into the four-way valve through the first channel, and the low-polarity oil phase simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel (i.e., the channel opposite to the first channel).

[0068] The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1 - 0.5:1, such as 0.1:1, 0.2:1. The flow rate of the raw material mixture is 0.2 - 1 mL / min, such as 0.5 mL / min.

[0069] Polymerization under ultraviolet light is in-situ ultraviolet crosslinking, the temperature is room temperature, the time is 1 - 8 min, such as 5 min; the wavelength is 200 - 400 nm, such as 254 nm.

[0070] In some embodiments of the present invention, the anion exchange includes:

[0071] Placing the polymerized beads in a packed column and adding a phosphate solution for elution to achieve anion exchange.

[0072] The concentration of the phosphate solution is 90 - 110 mmol / L, such as 100 mmol / L. The elution time is 46 - 50 h, such as 48 h.

[0073] The mass ratio of the beads to the phosphate solution is 1 - 2:100 - 150, such as 1.5:120.

[0074] The process of eluting with the phosphate solution is the anion exchange process. After anion exchange, the obtained beads are quaternary ammonium salt polymer catalysts.

[0075] After eluting with the phosphate solution, it also includes: washing and drying. The washing is carried out with deionized water.

[0076] In some embodiments of the present invention, the quaternary ammonium salt polymer catalyst is in the shape of beads, with a size of 0.2 - 3 mm, such as 2 - 2.2 mm, 1.7 - 1.9 mm.

[0077] The present invention also provides an application of the quaternary ammonium salt polymer catalyst described above, or the quaternary ammonium salt polymer catalyst prepared by the preparation method described above, in degrading organic pollutants in water treatment. The applicant has found that the quaternary ammonium salt polymer catalyst can be used to rapidly activate peroxides to generate reactive species such as dioxetanone and singlet oxygen, and then degrade organic pollutants. Therefore, an application of the quaternary ammonium salt polymer catalyst in degrading organic pollutants in water treatment is claimed.

[0078] The present invention also provides a method for treating organic pollutants in water, comprising the following steps:

[0079] Under the condition of aeration, the water body to be treated, the catalyst and the peroxide are mixed for degradation and mineralization to obtain the treated water body;

[0080] The catalyst is the quaternary ammonium salt polymer catalyst described above, or the quaternary ammonium salt polymer catalyst prepared by the preparation method described above.

[0081] Specifically, it includes:

[0082] The water body to be treated, the catalyst and the peroxide are placed in a reaction device, and nitrogen is introduced at the bottom of the reaction device for degradation and mineralization to obtain the treated water body.

[0083] Aeration can improve the mass transfer capacity of the system.

[0084] In some embodiments of the present invention, the organic pollutants in the water body to be treated include at least one of p-cresol, p-chlorophenol, 2,4-dichlorophenol, p-bromophenol, bisphenol F and phenol. In the water body to be treated, the concentration of the organic pollutant is 10-200 μmol / L, such as 100 μmol / L; the pH value is 5-11, such as 7.

[0085] In some embodiments of the present invention, the peroxide is selected from at least one of peracetic acid, sodium persulfate, potassium persulfate, ammonium persulfate, potassium monopersulfate, sodium monopersulfate and ammonium monopersulfate.

[0086] In some embodiments of the present invention, in the mixed water body, the concentration of the catalyst is 0.05-1 g / L, such as 0.4 g / L; the concentration of the peroxide is 0.1-50 mmol / L, such as 2 mmol / L.

[0087] In some embodiments of the present invention, the temperature of the degradation and mineralization is 5-40 °C, such as 25 °C.

[0088] In some embodiments of the present invention, the reaction device is a packed column. The water body to be treated, the catalyst and the peroxide are added in one pot.

[0089] The used catalyst can be regenerated. The specific methods include:

[0090] Soak the used catalyst in a solvent, and then rinse it with a phosphate solution to achieve the regeneration of the catalyst.

[0091] The solvent is selected from methanol and / or ethanol. The soaking temperature is 20-40°C; the time is 22-26h, such as 24h.

[0092] The mass concentration of the phosphate solution is 1.35%-1.65%. In the present invention, the catalyst is rinsed with the phosphate solution until there are no other impurity ions. The rinsing time is 10-20h.

[0093] In the present invention, the carbonyl functional group can generate a dioxetanone intermediate by activating a peroxide, and this intermediate further generates singlet oxygen active species. The introduction of a positively charged quaternary ammonium salt structure can enhance the activation ability of the carbonyl group and the oxidation ability of the dioxetanone, and the positive charge property can promote the enrichment of pollutants on the material surface and further improve the degradation rate.

[0094] The present invention chemically synthesizes a polymer precursor containing a positively charged quaternary ammonium salt through simple and mild reaction conditions. Using this precursor, a polymer material rich in high catalytic activity sites can be prepared by a specific method. At the same time, the present invention uses an oil-in-water microfluidic technology that is easy to scale up to achieve in-situ ultraviolet polymerization of polymer microspheres, and can be directly applied in a packed column widely used in practical applications, with simple operation. The catalyst microspheres prepared in the present invention have certain mechanical strength, antibacterial properties, and also have good anti-matrix ability. They can efficiently and selectively catalyze the degradation of organic pollutants in various agricultural and industrial wastewaters, and are easy to regenerate and reuse. At the same time, due to the simple production method, low production and regeneration costs of the catalyst in the present invention, it is easy to achieve large-scale industrial production and application, and has broad application prospects in water pollution control and water environment restoration.

[0095] The present invention has no special restrictions on the sources of raw materials used above, and they can be generally commercially available.

[0096] In order to further illustrate the present invention, the following examples are used to describe in detail a quaternary ammonium salt polymer catalyst, its preparation method and application provided by the present invention, but it should not be understood as a limitation to the protection scope of the present invention.

[0097] Example 1

[0098] 1) Weigh 50 g (0.18 mol) of tetradecyl bromide and 20 g (0.13 mol) of dimethylaminoethyl methacrylate, dissolve them in 100 mL of acetone, stir for 30 min, then react at 70 °C for 48 h. After the reaction, add ethyl acetate (the volume ratio of ethyl acetate to the reaction solution is 4:1), a large amount of white powder will precipitate. Separate the white powder with a suction funnel and dry it overnight at room temperature under vacuum to obtain the precursor material.

[0099] The precursor material obtained in the present invention was characterized. The characterization test was carried out on a Bruker AVANCE AVIII 400 liquid nuclear magnetic resonance instrument in the Physical and Chemical Experiment Center of the University of Science and Technology of China. Using deuterated DMSO as the solvent, nuclear magnetic resonance hydrogen spectrum data were obtained: δ (ppm) 6.10 (s, 1H), 5.75 (s, 1H), 4.51 (m, 2H), 3.68 (m, 2H), 3.35 (m, 2H), 3.10 (s, 6H), 1.85 (s, 3H), 1.76 (m, 23H), 0.88 (m, 3H), as Figure 2 shown. Figure 2 This is the nuclear magnetic resonance hydrogen spectrum of the precursor material prepared in Example 1 of the present invention. From Figure 2 it can be seen that the obtained precursor molecules have excellent purity and the synthesis method is simple and effective.

[0100] 2) Add 200 mg of the above-mentioned precursor material to a 1.5 mL centrifuge tube, add 100 mg of deionized water, heat and mix at 60 °C, then add 10 mg of photoinitiator (benzoin dimethyl ether) and 10 mg of crosslinking agent (1,4-butanediol dimethacrylate) and mix well to obtain a raw material mixture; transfer it to a syringe and assemble it with an injection pump. Through a four-way valve, a low-polarity oil phase (methyl silicone oil) flows into two opposite channels of the four-way valve at the same flow rate at the same time, and water-in-oil droplets are generated in the fourth channel. The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1:1, and the flow rate of the raw material mixture is 0.5 mL / min. The obtained water-in-oil droplets are polymerized at room temperature under ultraviolet light (wavelength 254 nm) for 5 min to form polymer microspheres. Place the polymer microspheres in a packed column, wash them with 100 mmol / L phosphate solution (the mass ratio of the polymer microspheres to the phosphate solution is 1.5:120) for 48 h, then wash them with deionized water and dry them to obtain a quaternary ammonium salt polymer catalyst (in the shape of microspheres, with a size of 2 - 2.2 mm).

[0101] The surface of the obtained quaternary ammonium salt polymer catalyst was analyzed by scanning electron microscopy: the surface morphology of the catalyst was characterized on a GeminiSEM 450 field emission scanning electron microscope in the Physical and Chemical Experiment Center of the University of Science and Technology of China, and the results are as Figure 3 shown. Figure 3This is the scanning electron micrograph of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention. From Figure 3 it can be seen that when the magnification reaches 10,000 times, after the catalyst pellets are ground into powder, the surface is flat with a small number of wrinkles.

[0102] X-ray energy spectrum analysis was carried out on the obtained quaternary ammonium salt polymer catalyst: the content analysis of C, N, O, and P elements of the catalyst was tested on a GeminiSEM 450 field emission scanning electron microscope in the Physical and Chemical Experiment Center of the University of Science and Technology of China. This instrument is equipped with an Oxford Aztec series X-ray energy spectrometer, and the results are as Figure 4 shown. Figure 4 This is the X-ray energy spectrum diagram of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention. From Figure 4 it can be seen that after ion exchange, the catalyst contains P element, which proves that the halogen ion has been successfully exchanged for phosphate ion.

[0103] Test on the adsorption capacity of the quaternary ammonium salt polymer catalyst:

[0104] At room temperature, 20 mL of phosphate buffer solution with pH = 7 was prepared, 20 mg of quaternary ammonium salt polymer catalyst was added, and 20 μmol / L of the colored pollutant rose bengal was added, and static adsorption was carried out for 60 min, as Figure 5 shown. Figure 5 This is the effect diagram of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention for adsorbing organic substances. From Figure 5 it can be seen that the organic substances are enriched on the surface of the polymer pellets (quaternary ammonium salt polymer catalyst), and the solution becomes clear, which proves that the material has the ability to adsorb organic substances.

[0105] Test on the decomposition of peroxide catalyzed by the quaternary ammonium salt polymer catalyst:

[0106] At room temperature, 50 mL of buffer solutions with different pH values (pH = 9, pH = 7) were prepared, 0.5 - 2 mmol / L of peroxymonosulfate (PMS, specifically sodium peroxymonosulfate) was added, and the decomposition of PMS without adding catalyst and with adding 20 - 50 mg of catalyst pellets was tested respectively by the iodometric method, as Figure 6 shown. Figure 6 This is the rate diagram of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention for catalyzing peroxide. From Figure 6 it can be seen that without adding catalyst, PMS hardly decomposes. With the addition of catalyst, PMS decomposes rapidly to generate reactive species, and pH = 9 has a better catalytic effect than pH = 7, which proves the catalytic decomposition ability of the material.

[0107] 3) Treatment of water body:

[0108] Add 500 mL of laboratory-prepared water (water to be treated) with a pH of 7 to the packed column. The organic pollutant contained therein is 2,4-dichlorophenol, with a concentration of 100 μmol / L. Then, add sodium monopersulfate and a quaternary ammonium salt polymer catalyst. In the resulting water body, the concentration of the catalyst is 0.4 g / L, and the concentration of sodium monopersulfate is 2 mmol / L. Introduce nitrogen gas at the bottom of the packed column and carry out degradation and mineralization at 25°C. Regularly take samples, filter the supernatant, and conduct high-performance liquid chromatography tests as Figure 7 shown. Figure 7 This is the adsorption and catalytic performance of the quaternary ammonium salt polymer catalyst prepared in Example 1 of the present invention in actual water bodies. Figure 7 The first figure in Figure 7 is the concentration change curve of 2,4-dichlorophenol in the solution after adding PMS; the first 90 min is the adsorption process, and then PMS is added, and the unadsorbed 2,4-dichlorophenol is degraded and removed. Figure 7 The second figure in

[0109] From Figure 7 the first figure, it can be seen that the catalyst can adsorb and enrich a large amount of pollutants on the surface (about 85%), and then start to oxidize and degrade. Within 10 min, the pollutants in the solution have been degraded. The remaining pollutants on the catalyst surface at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated as Figure 7 shown in the second figure of

[0110] Take the raw water in the actual environment and add 2,4-dichlorophenol as the experimental water. In the experimental water, the concentration of 2,4-dichlorophenol is 100 μmol / L; fill the quaternary ammonium salt polymer catalyst obtained from the material (step 2) into the packed column, continuously feed water and discharge water, and control the flow rate of the water body at 70 mL / h. The adsorption and oxidative degradation reactions occur when the water body passes through the material. Among them, the "material" group reflects the adsorption capacity of the material, and the material can achieve good adsorption and removal of 2,4-dichlorophenol (≥90%) within 260 h. The "material + PMS" group reflects the adsorption and catalytic oxidation capacity of the material. By adding PMS, the material can not only adsorb 2,4-dichlorophenol but also catalyze the degradation of 2,4-dichlorophenol by PMS, and can achieve good removal of 2,4-dichlorophenol (≥95%) within 360 h. The results are as Figure 7 shown in the third figure. It can be found that the material can also exhibit excellent adsorption and catalytic oxidation performance under the background of the actual environmental water body and has strong anti-matrix interference ability.

[0111] Example 2

[0112] The difference from Example 1 is that:

[0113] Step 2) is as follows:

[0114] Add 200 mg of the above-mentioned precursor material to a 1.5 mL centrifuge tube, add 200 mg of deionized water, heat and mix at 60 °C, then add 8 mg of photoinitiator (benzoin dimethyl ether) and 8 mg of cross-linking agent (1,4-butanediol dimethacrylate) and mix well to obtain a raw material mixture; transfer it to a syringe and assemble it with an injection pump. Through a four-way valve, a low-polarity oil phase (methyl silicone oil) simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1:1, and the flow rate of the raw material mixture is 0.5 mL / min. The obtained water-in-oil droplets are polymerized at room temperature for 5 min under ultraviolet light (wavelength 254 nm) to form polymer beads. Place the polymer beads in a packed column, wash them with 100 mmol / L phosphate solution (the mass ratio of the polymer beads to the phosphate solution is 1.5:120) for 48 h, then wash them with deionized water and dry them to obtain a quaternary ammonium salt polymer catalyst (in the shape of beads, with a size of 1.7 - 1.9 mm).

[0115] All the remaining steps are the same as those in Example 1. Samples were taken at regular intervals, and the supernatant was filtered for high-performance liquid chromatography testing. The results showed that the catalyst could adsorb and enrich a large amount of pollutants on its surface (about 90%), and then began to oxidize and degrade. Within 10 minutes, the pollutants in the solution had been degraded completely. The remaining pollutants on the catalyst surface at different reaction time points were obtained by methanol extraction, and the total degradation rate of the pollutants was calculated from this. It can be seen that the pollutants were completely degraded in all phases within 15 minutes.

[0116] Comparative Example 1

[0117] The difference from Example 2 is that the mass ratio of the precursor material, photoinitiator, and crosslinker is 2:0.005:0.005.

[0118] Specifically, step 2) is as follows:

[0119] Add 200 mg of the above-mentioned precursor material to a 1.5 mL centrifuge tube, add 200 mg of deionized water, heat and mix at 60 °C, then add 0.5 mg of the photoinitiator (benzoin dimethyl ether) and 0.5 mg of the crosslinker (1,4-butanediol dimethacrylate) and mix well to obtain a raw material mixture. Transfer it to a syringe and assemble it with an injection pump. Through a four-way valve, the low-polarity oil phase (methyl silicone oil) simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1:1, and the flow rate of the raw material mixture is 0.5 mL / min. The obtained water-in-oil droplets are polymerized at room temperature for 5 minutes under ultraviolet light (wavelength 254 nm) to form polymer microspheres. Place the polymer microspheres in a packed column, wash them with 100 mmol / L phosphate solution (the mass ratio of the polymer microspheres to the phosphate solution is 1.5:120) for 48 hours, then wash them with deionized water and dry them to obtain a quaternary ammonium salt polymer catalyst (in the shape of microspheres, with a size of 1.7 - 1.9 mm).

[0120] All the remaining steps are the same as those in Example 1. Samples were taken at regular intervals, and the supernatant was filtered for high-performance liquid chromatography testing. The results showed that the catalyst could adsorb and enrich a large amount of pollutants on its surface (about 70%), and then began to oxidize and degrade. Within 25 minutes, the pollutants in the solution were degraded completely. The remaining pollutants on the catalyst surface at different reaction time points were obtained by methanol extraction, and the total degradation rate of the pollutants was calculated from this. It can be seen that the pollutants were completely degraded in all phases within 35 minutes.

[0121] Comparative Example 2

[0122] The difference from Example 2 is that the mass ratio of the precursor material, photoinitiator, and crosslinker is 2:1:1.

[0123] Specifically, step 2) is as follows:

[0124] Add 200 mg of the above-mentioned precursor material to a 1.5 mL centrifuge tube, add 200 mg of deionized water, heat and mix at 60 °C, then add 100 mg of photoinitiator (benzoin dimethyl ether) and 100 mg of crosslinking agent (1,4-butanediol dimethacrylate) and mix well to obtain a raw material mixture; transfer it to a syringe and assemble it with an injection pump. Through a four-way valve, a low-polarity oil phase (methyl silicone oil) simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. The flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.1:1, and the flow rate of the raw material mixture is 0.5 mL / min. The obtained water-in-oil droplets are polymerized at room temperature for 5 min under ultraviolet light (wavelength 254 nm) to form polymer microspheres. Place the polymer microspheres in a packed column, wash with 100 mmol / L phosphate solution (the mass ratio of the polymer microspheres to the phosphate solution is 1.5:120) for 48 h, then wash with deionized water and dry to obtain a quaternary ammonium salt polymer catalyst (in the shape of microspheres, with a size of 2.4 - 2.6 mm).

[0125] All the remaining steps are the same as in Example 1. Samples are taken at regular intervals, the supernatant is filtered and subjected to high-performance liquid chromatography testing. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 50%), and then start to oxidize and degrade. Within 40 min, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated therefrom. It can be seen that the pollutants have achieved complete degradation in all phases within 60 min.

[0126] Example 3

[0127] The difference from Example 1 is that:

[0128] In step 2), the flow rate ratio of the raw material mixture to the low-polarity oil phase is 0.2:1.

[0129] All the remaining steps are the same as in Example 1. Samples are taken at regular intervals, the supernatant is filtered and subjected to high-performance liquid chromatography testing. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 75%), and then start to oxidize and degrade. Within 25 min, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated therefrom. It can be seen that the pollutants have achieved complete degradation in all phases within 30 min.

[0130] Comparative Example 3

[0131] The difference from Example 2 is that: the flow rate ratio of the raw material mixture droplets to the low-polarity oil phase is 1:1.

[0132] Specifically, step 2) is as follows:

[0133] 2) Add 200 mg of the above-mentioned precursor material into a 1.5 mL centrifuge tube, add 100 mg of deionized water, heat and mix at 60 °C, then add 10 mg of photoinitiator (benzoin dimethyl ether) and 10 mg of crosslinking agent (1,4-butanediol dimethacrylate) and mix well to obtain a raw material mixture; transfer it to a syringe and assemble it with an injection pump. Through a four-way valve, a low-polarity oil phase (methyl silicone oil) simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. The flow rate ratio of the raw material mixture to the low-polarity oil phase is 1:1, and the flow rate of the raw material mixture is 0.5 mL / min. The obtained water-in-oil droplets are polymerized at room temperature for 5 min under ultraviolet light (wavelength 254 nm) to form polymer microspheres. Place the polymer microspheres in a packed column, wash with 100 mmol / L phosphate solution (the mass ratio of the polymer microspheres to the phosphate solution is 1.5:120) for 48 h, then wash with deionized water and dry to obtain a quaternary ammonium salt polymer catalyst (in the form of microspheres, with a size of 3.2 - 3.4 mm).

[0134] The remaining steps are the same as those in Example 1. Samples are taken at regular intervals, and the supernatant is filtered for high-performance liquid chromatography testing. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 50%), and then start to oxidize and degrade. Within 45 min, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated from this. It can be seen that the pollutants have achieved complete degradation in all phases within 65 min.

[0135] Comparative Example 4

[0136] The difference from Example 2 is that the flow rate ratio of the raw material mixture droplets to the low-polarity oil phase is 1:0.1.

[0137] The experimental results show that at this ratio, water-in-oil droplets cannot be formed well, which will cause the raw material mixture to accumulate together and polymerize into irregular-shaped products.

[0138] According to the method of Example 1, samples are taken at regular intervals for the supernatant of the irregular-shaped product for high-performance liquid chromatography testing. The results show that the irregular product can adsorb and enrich a large amount of pollutants on its surface (about 45%), and then start to oxidize and degrade. Within 50 min, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated from this. It can be seen that the pollutants have achieved complete degradation in all phases within 70 min.

[0139] Example 4

[0140] The difference from Example 1 is as follows:

[0141] In step 3), the pH value of the laboratory-prepared water (water to be treated) is adjusted to 5.

[0142] The temperature for degradation and mineralization is adjusted to 10 °C.

[0143] The remaining steps are the same as those in Example 1. Samples are taken regularly, the supernatant is filtered, and high-performance liquid chromatography (HPLC) tests are performed. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 60%), and then start oxidative degradation. Within 30 minutes, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated therefrom. It can be seen that the pollutants have achieved complete degradation in all phases within 40 minutes.

[0144] Example 5

[0145] The difference from Example 1 is as follows:

[0146] In step 3), the pH value of the laboratory-prepared water (water to be treated) is adjusted to 11.

[0147] The temperature for degradation and mineralization is adjusted to 40 °C.

[0148] The remaining steps are the same as those in Example 1. Samples are taken regularly, the supernatant is filtered, and high-performance liquid chromatography (HPLC) tests are performed. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 95%), and then start oxidative degradation. Within 5 minutes, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated therefrom. It can be seen that the pollutants have achieved complete degradation in all phases within 10 minutes.

[0149] Example 6

[0150] The difference from Example 1 is as follows:

[0151] In step 3), the organic pollutant contained in the laboratory-prepared water (water to be treated) is p-cresol.

[0152] The remaining steps are the same as those in Example 1. Samples are taken regularly, the supernatant is filtered, and high-performance liquid chromatography (HPLC) tests are performed. The results show that the catalyst can adsorb and enrich a large amount of pollutants on its surface (about 70%), and then start oxidative degradation. Within 10 minutes, the pollutants in the solution have been degraded completely. The remaining pollutants on the surface of the catalyst at different reaction time points are obtained by methanol extraction, and the total degradation rate of the pollutants is calculated therefrom. It can be seen that the pollutants have achieved complete degradation in all phases within 20 minutes.

[0153] Example 7

[0154] The difference from Example 1 is as follows:

[0155] In step 3), the organic pollutant contained in the laboratory-prepared water (water to be treated) is 4-chlorophenol.

[0156] The remaining steps are the same as those in Example 1. Samples were taken regularly, the supernatant was filtered, and high-performance liquid chromatography (HPLC) tests were performed. The results showed that the catalyst could adsorb and enrich a large amount of pollutants on its surface (about 80%), and then began to oxidize and degrade. Within 10 minutes, the pollutants in the solution had been completely degraded. The remaining pollutants on the surface of the catalyst at different reaction time points were obtained by methanol extraction, and the total degradation rate of the pollutants was calculated from this. It can be seen that the pollutants were completely degraded in all phases within 20 minutes.

[0157] Example 8

[0158] The difference from Example 1 is as follows:

[0159] In step 3), the organic pollutant contained in the laboratory-prepared water (water to be treated) is bisphenol F.

[0160] The remaining steps are the same as those in Example 1. Samples were taken regularly, the supernatant was filtered, and high-performance liquid chromatography (HPLC) tests were performed. The results showed that the catalyst could adsorb and enrich a large amount of pollutants on its surface (about 85%), and then began to oxidize and degrade. Within 10 minutes, the pollutants in the solution had been completely degraded. The remaining pollutants on the surface of the catalyst at different reaction time points were obtained by methanol extraction, and the total degradation rate of the pollutants was calculated from this. It can be seen that the pollutants were completely degraded in all phases within 15 minutes.

[0161] Example 9

[0162] The difference from Example 1 is as follows:

[0163] In step 3), the organic pollutant contained in the laboratory-prepared water (water to be treated) is phenol.

[0164] The remaining steps are the same as those in Example 1. Samples were taken regularly, the supernatant was filtered, and high-performance liquid chromatography (HPLC) tests were performed. The results showed that the catalyst could adsorb and enrich a large amount of pollutants on its surface (about 75%), and then began to oxidize and degrade. Within 10 minutes, the pollutants in the solution had been completely degraded. The remaining pollutants on the surface of the catalyst at different reaction time points were obtained by methanol extraction, and the total degradation rate of the pollutants was calculated from this. It can be seen that the pollutants were completely degraded in all phases within 20 minutes.

[0165] The description of the above embodiments is only used to help understand the method and its core idea of the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A quaternary ammonium salt polymer catalyst is prepared by generating water-in-oil droplets from a raw material mixture solution including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidic technology, polymerizing under ultraviolet light irradiation, and then performing anion exchange. The precursor material is prepared by reacting raw materials including an acrylate and a halogenated alkane.

2. The quaternary ammonium salt polymer catalyst according to claim 1, wherein The acrylate includes one or more of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, and 3-(dimethylamino)ethyl acrylate; the halogenated alkane includes one or more of 1-bromoundecane, 1-bromododecane, 1-bromotetradecane, 1-bromohexadecane, 1-bromoeicosane, 1-chlorododecane, 1-chlorotetradecane, and 1-chlorohexadecane. The molar ratio of the acrylate to the halogenated alkane is 1:1 - 10.

3. The quaternary ammonium salt polymer catalyst according to claim 1, wherein The preparation method of the precursor material includes the following steps: Mix the acrylate, the halogenated alkane, and an organic solvent, and then carry out a reaction to obtain the precursor material. The organic solvent is selected from at least one of acetone, acetonitrile, and methanol. After the reaction, it further includes: mixing the reaction solution with a low-polarity solvent to precipitate a white precipitate, and obtaining the precursor material after suction filtration and drying. The low-polarity solvent is selected from one of n-hexane, ethyl acetate, and petroleum ether.

4. The quaternary ammonium salt polymer catalyst according to claim 1, wherein The photoinitiator is selected from at least one of benzoin dimethyl ether, 4-chlorobenzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and methyl o-benzoylbenzoate. The crosslinking agent is an ester crosslinking agent, specifically selected from one of 1,4-butanediol dimethacrylate, ethylene glycol dimethacrylate, hexanediol dimethacrylate, and trimethylolpropane trimethacrylate. The mass ratio of the precursor material to water is 0.5 - 2:

1. The mass ratio of the precursor material, the photoinitiator, and the crosslinking agent is 0.5 - 2:0.01 - 0.05:0.01 - 0.

05.

5. A preparation method of the quaternary ammonium salt polymer catalyst according to any one of claims 1 - 4, including the following steps: Generate water-in-oil droplets from a raw material mixture solution including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidic technology, polymerize under ultraviolet light irradiation, and then perform anion exchange to obtain the quaternary ammonium salt polymer catalyst.

6. The preparation method according to claim 5, wherein Generating water-in-oil droplets from a raw material mixture solution including a precursor material, water, a photoinitiator, and a crosslinking agent through microfluidic technology specifically includes: After heating and mixing the precursor material and water, add the photoinitiator and the crosslinking agent and mix well. Using microfluidic technology, the raw material mixture solution flows into a four-way valve, and a low-polarity oil phase simultaneously flows into two opposite channels of the four-way valve at the same flow rate, and water-in-oil droplets are generated in the fourth channel. The temperature for heating and mixing is 40 - 80 °C. The low-polarity oil phase includes at least one of methyl silicone oil, ethyl silicone oil, and methylphenyl silicone oil. The flow rate ratio of the raw material mixture solution to the low-polarity oil phase is 0.1 - 0.5:

1.

7. The preparation method according to claim 5, characterized in that, The temperature for polymerization under ultraviolet light irradiation is room temperature, the time is 1 - 8 min, and the wavelength is 200 - 400 nm. The anion exchange includes: Placing the polymerized spheres in a packed column, and adding a phosphate solution for elution to achieve anion exchange. The concentration of the phosphate solution is 90 to 110 mmol / L; The time for elution is 46 to 50 h.

8. Use of the quaternary ammonium salt polymer catalyst according to any one of claims 1 to 4, or the quaternary ammonium salt polymer catalyst prepared by the preparation method according to any one of claims 5 to 7, in the degradation of organic pollutants in water treatment.

9. A method for treating organic pollutants in water, comprising the following steps: Under the condition of aeration, the water body to be treated, the catalyst and the peroxide are mixed for degradation and mineralization to obtain the treated water body; The catalyst is the quaternary ammonium salt polymer catalyst according to any one of claims 1 to 4, or the quaternary ammonium salt polymer catalyst prepared by the preparation method according to any one of claims 5 to 7.

10. The processing method according to claim 9, characterized in that, The organic pollutants in the water body to be treated include at least one of p-cresol, p-chlorophenol, 2,4-dichlorophenol, p-bromophenol, bisphenol F and phenol; In the water body to be treated, the concentration of the organic pollutants is 10 to 200 μmol / L, and the pH value is 5 to 11; The peroxide includes at least one of peracetic acid, sodium persulfate, potassium persulfate, ammonium persulfate, potassium monopersulfate, sodium monopersulfate and ammonium monopersulfate; In the mixed water body, the concentration of the catalyst is 0.05 to 1 g / L, and the concentration of the peroxide is 0.1 to 50 mmol / L; The temperature of the degradation and mineralization is 5 to 40 °C.

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