Antibacterial multifunctional nanofiber membrane with porous structure for synergistic adsorption of uranium and preparation method thereof

Abstract

The application discloses a kind of porous structure antibacterial type bifunctional synergic uranium adsorption nanofiber membrane and preparation method thereof, first configure fiber spinning solution, then prepare nanofiber membrane by electrospinning technology, and after washing and removing pore forming agent, antibacterial type bifunctional synergic uranium adsorption nanofiber membrane with porous structure is obtained.The application uses electrospinning technology and combines phase separation technology to prepare porous antibacterial type uranium adsorption nanofiber, which is applied to seawater uranium extraction and wastewater treatment field, can effectively improve the adsorption effect of the material and reduce the interference effect of water microorganism, realize the development and utilization of waste textile fiber, and has important practical significance for the development of new environment-friendly high-efficiency adsorbent and efficient adsorption of seawater uranium.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of seawater uranium extraction and antibacterial, and particularly relates to an antibacterial dual-functional group synergistic nanofiber membrane with a porous structure for adsorbing uranium and a preparation method thereof. BACKGROUND

[0002] With the rapid development of nuclear energy, the global consumption and demand for uranium resources are increasing, and the traditional ore mining cannot meet the long-term demand for uranium, and the gap of uranium fuel is further expanded. Seawater and discharged industrial wastewater containing uranium are extremely potential uranium supply resources, and if they can be effectively utilized, they can supplement certain uranium resources to meet the energy demand of human beings.

[0003] The total amount of the world's oceans is about 1.37 x 10 12 m 3 The average concentration of uranium in seawater is 3.3 μg·L -1 , and the total reserves of uranium elements reach 429 million tons, which is nearly 1000 times of the land reserves, and if it can be reasonably developed and utilized, it will provide a large amount of resources for nuclear energy raw materials.

[0004] The water-soluble pore-forming agent has the advantages of simple pore-forming method and easy operation. Polyvinylpyrrolidone (PVP) is a non-ionic surfactant and does not affect the raw materials. It has certain advantages when used as a structure regulator of nanofiber.

[0005] Polymer adsorbent is the most promising adsorbent material for large-scale seawater operation at present. The amidoxime group material has high adsorption selectivity and affinity, and becomes the first choice for seawater uranium extraction. The amidoxime group is mainly obtained by the reaction of a substance containing a cyano group with hydroxylamine. At present, the amidoxime group fiber adsorbent has become the main research direction of large-scale seawater uranium extraction material.

[0006] Nanofiber refers to a linear material with a certain length ratio and a nanometer scale diameter and a large length. In a narrow sense, the diameter of nanofiber is between 1 nm and 100 nm, but in a broad sense, the fiber with a diameter less than 1000 nm can be called nanofiber. There are many methods for manufacturing nanofiber, and electrospinning is widely used due to its simple operation, wide practical range and relatively high production efficiency. The nanofiber adsorbent material is selected as the main material for seawater uranium extraction, which has a large specific surface area and can be in full contact with seawater. However, the existing nanofiber for adsorbing uranium cannot hinder bacteria, fungi and other microorganisms, which can easily damage the adsorbent material and reduce the adsorption effect, and the adsorbent material cannot be recycled. SUMMARY

[0007] The present application is to solve the existing technology for adsorbing uranium polymer material adsorption effect is not good and the adsorption material is difficult to destroy the role of hindering microorganisms, and its purpose is to provide a porous structure of antibacterial type dual functional group synergistic uranium adsorption nanofiber membrane and its preparation method.

[0008] The present application is realized by the following technical solutions:

[0009] A preparation method of an antibacterial type dual functional group synergistic uranium adsorption nanofiber membrane with a porous structure, comprising the following steps:

[0010] (I) configuring a fiber spinning solution

[0011] The amidoamine, polyaminophosphoric acid and pore-forming agent are sequentially added to the solvent, and the nanofiber spinning solution is obtained by mixing and stirring;

[0012] (II) preparing a nanofiber membrane by electrospinning technology

[0013] The fiber spinning solution configured in step (I) is stretched and accumulated into a nanofiber membrane by electrospinning technology under the action of electric field force;

[0014] (III) cleaning and removing the pore-forming agent

[0015] The nanofiber membrane obtained in step (II) is soaked in deionized water, then cleaned with deionized water and dried, thereby obtaining an antibacterial type dual functional group synergistic uranium adsorption nanofiber membrane with a porous structure.

[0016] In the above technical solution, the pore-forming agent is polyvinylpyrrolidone; the solvent is N,N'-dimethylformamide; and the stirring time of step (I) is 20h-26h.

[0017] In the above technical solution, the mass ratio of the amidoamine, polyaminophosphoric acid and pore-forming agent is (2.5-4):5:(3-4); the mass-volume ratio of the amidoamine to the solvent is 1:(8-12); and the mass fraction of the polyaminophosphoric acid in the nanofiber spinning solution of step (I) is 8%-15%.

[0018] In the above technical solution, the specific operation of the electrospinning technology of step (II) is as follows: the fiber spinning solution configured in step (I) is placed in a 10ml syringe, and under the conditions of a temperature of 35℃-39℃, a humidity of 30%-50%, a voltage difference of 16kV-18kV, a static spinning needle aperture of 20G, a needle distance from the receiving plate of 15cm-20cm, and a syringe pump speed of 0.8ml / h-1.5ml / h, the fiber spinning solution is stretched and accumulated into a nanofiber membrane by the action of electric field force.

[0019] In the technical scheme, the soaking time of step (III) is 12-18 hours; and the drying condition is that the temperature is 55-65 DEG C and the drying time is 10-12 hours.

[0020] In the technical scheme, the preparation method of the amidoxime comprises the following steps:

[0021] (i) mixing hydroxylamine hydrochloride and N,N'-dimethylformamide, adding sodium hydroxide after the hydroxylamine hydrochloride is completely dissolved, and stirring vigorously;

[0022] (ii) adding polyacrylonitrile powder to the solution of step (i), stirring until the polyacrylonitrile is completely swelled, continuing to stir under heating until the reaction is completed, and centrifuging to obtain the supernatant, which is the amidoxime spinning solution;

[0023] (iii) injecting the amidoxime spinning solution of step (ii) into methanol through a syringe to obtain white granular precipitate;

[0024] (iv) washing and drying the white granular precipitate obtained in step (iii) to obtain the amidoxime.

[0025] In the technical scheme, the mass ratio of the hydroxylamine hydrochloride and N,N'-dimethylformamide is (2.5-4):25; the mass ratio of the sodium hydroxide and the hydroxylamine hydrochloride is (20-26):40; and the mass ratio of the polyacrylonitrile and the hydroxylamine hydrochloride is (16-19):25.

[0026] In the technical scheme, the preparation method of the polyaminophosphoric acid comprises the following steps:

[0027] (i) stirring a solid phosphorous acid into a liquid state, adding polyacrylonitrile powder to the liquid, and continuing to stir until the polyacrylonitrile is fully swelled to obtain a yellow-brown thick liquid;

[0028] (ii) injecting the yellow-brown thick liquid obtained in step (i) into deionized water through a syringe to precipitate a light yellow solid, and separating, washing and drying the light yellow solid to obtain the polyaminophosphoric acid.

[0029] In the technical scheme, the mass ratio of the solid phosphorous acid and the polyacrylonitrile is (8-15):1, preferably 6:1, 8:1 or 10:1.

[0030] The antibacterial multifunctional nanofiber membrane with a porous structure and capable of synergistically adsorbing uranium is prepared by a preparation method of the antibacterial multifunctional nanofiber membrane with a porous structure and capable of synergistically adsorbing uranium.

[0031] The present application has the following advantages:

[0032] The application provides a porous antibacterial bifunctional synergistic uranium adsorption nanofiber membrane and a preparation method thereof. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 It is a microstructure diagram of the nanofiber of the application.

[0034] Figure 2 It is an infrared spectrum diagram of the synthesized polyaminophosphoric acid of the application.

[0035] For those skilled in the art, other related drawings can be obtained according to the above drawings without creative labor. DETAILED DESCRIPTION

[0036] In order to make the person in the art better understand the technical scheme of the application, the technical scheme of the application is further illustrated by specific embodiments in combination with the drawings of the specification.

[0037] A preparation method of a porous antibacterial bifunctional synergistic uranium adsorption nanofiber membrane, comprising the following steps:

[0038] (I) configuring a fiber spinning solution

[0039] The amine oxime, the polyaminophosphoric acid and the pore-forming agent are sequentially added into the solvent, and the nanofiber spinning solution is obtained by mixing and stirring;

[0040] The pore-forming agent is polyvinylpyrrolidone with good water solubility;

[0041] The solvent is N,N'-dimethylformamide (DMF) which is easy to evaporate;

[0042] The stirring time is 20h-26h;

[0043] The mass ratio of the amidoxime, polyaminophosphoric acid and pore-forming agent is (2.5-4):5:(3-4).

[0044] The mass-volume ratio of the amidoxime and solvent is 1:8-12.

[0045] The preparation method of the amidoxime comprises the following steps:

[0046] (i) 5g-8g of hydroxylamine hydrochloride is weighed in a 250mL round-bottom flask, 40mL-55mL of N,N'-dimethylformamide is measured by a measuring cylinder and added into the round-bottom flask, and then mechanical stirring is used for stirring until the hydroxylamine hydrochloride is completely dissolved, and then 3g-5g of sodium hydroxide is added and stirred vigorously for 30min-50min;

[0047] (ii) 4g-7g of polyacrylonitrile powder is added into the above solution and stirred for a certain time to make it completely swell into the DMF system, and then the temperature is raised to 80°C-100°C and mechanical stirring is used for 12h-18h, and then a light yellow mixture is obtained after the reaction is completed, and the bottom solid is removed after centrifugation three times by using a high-speed centrifuge to obtain a light yellow supernatant, that is, a clear amidoxime spinning solution is obtained;

[0048] (iii) the spinning solution of step (ii) is slowly injected into 300mL-500mL of methanol by using a syringe to obtain white particles after solidification, and a glass rod is used for continuously stirring to crush them into white small particle precipitates;

[0049] (iv) the white particle solid obtained in step (iii) is suction filtered and washed several times with methanol, and then vacuum dried at 50°C-60°C for 24h to obtain a solid, which is ground into a solid powder by using a mortar for standby, that is, the raw material amidoxime.

[0050] The preparation method of the polyaminophosphoric acid comprises the following steps:

[0051] (i) after solid phosphorous acid is dissolved into a liquid state under magnetic stirring at 80°C-100°C, polyacrylonitrile powder is added in a certain proportion, the temperature is raised to 120°C-180°C (preferably 140°C-160°C), and condensation reflux and magnetic stirring are used for 8h-12h (preferably 10h-12h) to make the polyacrylonitrile swell sufficiently, and finally a yellow-brown thick liquid state is obtained; the mass ratio of the solid phosphorous acid and polyacrylonitrile is (8-15):1, and preferably 6:1, 8:1 or 10:1;

[0052] (ii) Prepare 200 mL to 500 mL of deionized water under magnetic stirring, slowly inject the yellow-brown thick liquid in step (i) into the deionized water with a syringe to precipitate light yellow solid, stir the obtained solid-liquid mixture for 2 h to 3 h to make the yellow-brown liquid precipitate, and then filter out the light yellow solid, wash it several times with deionized water, and finally wash it several times with ethanol, and then put it into an oven to dry for 12 h to 18 h to obtain the multifunctional antibacterial uranium adsorption raw material polyamino phosphoric acid;

[0053] (II) Preparation of nanofiber membrane by electrospinning technology

[0054] The fiber spinning solution prepared in step (I) is subjected to electrospinning technology to stretch and accumulate into a nanofiber membrane under the action of electric field force;

[0055] Specifically,

[0056] The fiber spinning solution prepared in step (I) is placed in a 10 ml syringe, and under the conditions of a temperature of 35°C to 39°C, a humidity of 30% to 50%, a voltage difference of 16 kV to 18 kV, a static spinning needle aperture of 20G, a needle distance from the receiving plate of 15 cm to 20 cm, and a syringe pump speed of 0.8 ml / h to 1.5 ml / h, the fiber spinning solution is stretched and accumulated into a nanofiber membrane under the action of electric field force;

[0057] (III) Cleaning and removing the pore-forming agent

[0058] The nanofiber membrane obtained in step (II) is soaked in deionized water, and then dried after being washed with deionized water to obtain a porous antibacterial nanofiber membrane with dual functional group synergistic uranium adsorption.

[0059] The soaking time is 12 h to 18 h, and the drying conditions are a temperature of 55°C to 65°C and a drying time of 10 h to 12 h.

[0060] The nanofiber itself has a high specific surface area due to its nanoscale fiber structure, and the pore structure of the fiber is adjusted during the spinning process, which further increases the specific surface area of the material.

[0061] Example 1

[0062] A preparation method of an amidoxime, comprising the following steps:

[0063] (i) Weigh 4.8 g of hydroxylamine hydrochloride into a 250 mL round-bottom flask, use a graduated cylinder to measure 40 mL of N,N'-dimethylformamide and add it into the round-bottom flask, then use mechanical stirring to stir until the hydroxylamine hydrochloride is completely dissolved, and then add 3 g of sodium hydroxide and stir vigorously for 40 min;

[0064] (ii) Add 3.5 g of polyacrylonitrile powder to the above solution and stir for a certain period of time to make it fully swell into the DMF system, and then heat to 120℃ and mechanically stir for 12h. After the reaction is completed, a light yellow mixture is obtained. After centrifugation three times by using a high-speed centrifuge, the bottom solid is removed to obtain a light yellow supernatant, which is a clear amidoxime spinning solution;

[0065] (iii) Slowly inject the spinning solution of step (ii) into 300 mL of methanol by using a syringe to obtain white particles after solidification, and continuously stir them with a glass rod to crush them into white small particle precipitates;

[0066] (iv) Filter the white particle solid obtained in step (iii) and wash it with methanol several times, and then vacuum dry it at 60℃ for 24h to obtain a solid which is ground into a solid powder for use as raw material amidoxime.

[0067] A preparation method of a polyaminophosphonic acid capable of inhibiting microorganisms in water bodies and simultaneously efficiently adsorbing uranium includes the following steps:

[0068] (i) Dissolve solid phosphorous acid into a liquid state at 80℃ under magnetic stirring, and then add polyacrylonitrile powder into the polyacrylonitrile powder at a mass ratio of 6:1. Heat the temperature to 140℃, condense reflux and magnetically stir for 8h to make the polyacrylonitrile fully swell, and finally obtain a yellow-brown thick liquid state;

[0069] (ii) Prepare 300 mL of deionized water under magnetic stirring, and slowly inject the yellow-brown thick liquid of step (i) into the deionized water by using a syringe to precipitate a light yellow solid. Stir the obtained solid-liquid mixture for 2h to make the yellow-brown liquid precipitate, and then filter out the light yellow solid and wash it with deionized water several times. Finally, wash it with ethanol several times and then put it into an oven to dry for 12h to obtain multifunctional antibacterial uranium adsorption raw material polyaminophosphonic acid.

[0070] A preparation method of an antibacterial type nanofiber membrane with a porous structure and capable of synergistically adsorbing uranium with double functional groups includes the following steps:

[0071] (I) Configure a nanofiber spinning solution

[0072] Add 1g of amidoxime, 1.2g of polyaminophosphonic acid and 0.8g of water-soluble pore-forming agent polyvinylpyrrolidone into 10ml of solvent N,N'-dimethylformamide (DMF) in sequence, and mix and stir to prepare a nanofiber spinning solution with a mass fraction of 8%;

[0073] (II) Prepare a nanofiber membrane by using electrospinning technology

[0074] The fiber spinning solution configured in step (I) is stretched and accumulated into a nanofiber membrane by using electrospinning technology under the action of electric field force.

[0075] Specifically:

[0076] The fiber spinning solution prepared in step (I) was placed into a 10ml syringe. Under the conditions of a temperature of 35℃, a humidity of 40%, a voltage difference of 18kV, an electrospinning needle aperture of 20G, a needle distance of 18cm from the receiving plate, and an injection pump speed of 0.8ml / h, the fiber spinning solution was stretched and stacked into a nanofiber membrane by the action of an electric field.

[0077] (III) Cleaning and removing pore-forming agent

[0078] The nanofiber membrane obtained in step (II) is immersed in deionized water, then washed with deionized water and dried to obtain a nanofiber membrane with a porous structure that is antibacterial and has dual functional groups that synergistically adsorb uranium.

[0079] The soaking time is 12 hours; the drying conditions are: temperature 55℃, drying time 10 hours.

[0080] The microstructure of the prepared nanofibers is as follows Figure 1 As shown, by Figure 1 It is evident that the nanofibers are evenly distributed, exhibiting good fiber morphology. The fiber membrane shows no clumping, and the fiber diameter distribution is relatively uniform, indicating that the electrospinning conditions are quite suitable.

[0081] Figure 2 The spectrum of PAN in the image is the infrared spectrum of polyacrylonitrile, and the spectrum of PPAN is the infrared spectrum of polyaminophosphoric acid, where 2243 cm⁻¹ is the focal length. -1 The characteristic functional group corresponding to polyacrylonitrile, cyano C≡N, is 1220 cm⁻¹. -1 The characteristic functional group P=O corresponding to polyaminophosphoric acid is 910 cm⁻¹. -1 1072cm -1 The characteristic functional groups PO and CPO corresponding to polyaminophosphoric acid are 570 cm⁻¹. -1 773cm -1 The corresponding characteristic functional group is POC, which corresponds to polyaminophosphoric acid.

[0082] Example 2

[0083] The amine oximes used in this embodiment are the same as those prepared by the method in Example 1;

[0084] In this embodiment, polyaminophosphoric acid was prepared using the method of Example 1, with the only difference being the mass ratio of solid phosphorous acid to polyacrylonitrile powder. In this embodiment, the mass ratio of solid phosphorous acid to polyacrylonitrile powder is 8:1.

[0085] A method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption includes the following steps:

[0086] (I) Preparation of fiber spinning solution

[0087] 1.2 g of amidoxime, 1.2 g of polyaminophosphoric acid and 0.6 g of water-soluble pore-forming agent polyvinylpyrrolidone were sequentially added into 10 ml of solvent N,N'-dimethylformamide (DMF) and mixed and stirred to prepare a nanofiber spinning solution with a mass fraction of 8%;

[0088] (II) Preparation of nanofiber membrane by electrospinning technology

[0089] The fiber spinning solution prepared in step (I) was stretched and accumulated into a nanofiber membrane by electrospinning technology under the action of electric field force;

[0090] Specifically,

[0091] The fiber spinning solution prepared in step (I) was placed in a 10 ml syringe, and under the conditions of a temperature of 35℃, a humidity of 40%, a voltage difference of 18 kV, a needle head aperture of 20G, a needle head distance from the receiving plate of 18 cm, and a syringe pump speed of 1 ml / h, the fiber spinning solution was stretched and accumulated into a nanofiber membrane by the action of electric field force;

[0092] (III) Removal of pore-forming agent

[0093] The nanofiber membrane obtained in step (II) was soaked in deionized water and then washed with deionized water and dried to obtain a porous antibacterial nanofiber membrane with dual functional groups synergistically adsorbing uranium.

[0094] The soaking time is 12 h; the drying conditions are a temperature of 55℃ and a drying time of 12 h.

[0095] Example 3

[0096] The amidoxime used in this example is the same as that prepared by the method of Example 1.

[0097] In this example, the polyaminophosphoric acid was prepared by the method of Example 1, and only the mass ratio of solid phosphorous acid and polyacrylonitrile powder was different, and in this example, the mass ratio of solid phosphorous acid and polyacrylonitrile powder was 10:1.

[0098] A method for preparing a porous antibacterial nanofiber membrane with dual functional groups synergistically adsorbing uranium, comprising the following steps:

[0099] (I) Preparation of fiber spinning solution

[0100] 1.5g of amidoxime, 1g of polyaminophosphoric acid and 0.8g of water-soluble pore-forming agent polyvinylpyrrolidone are sequentially added into 10ml of solvent N,N'-dimethylformamide (DMF) to prepare a nanofiber spinning solution with a mass fraction of 11.7%;

[0101] (II) preparing a nanofiber membrane by electrospinning technology

[0102] The fiber spinning solution prepared in step (I) is stretched and accumulated into a nanofiber membrane by electrospinning technology under the action of electric field force.

[0103] Specifically,

[0104] The fiber spinning solution prepared in step (I) is placed into a 10ml syringe, and under the conditions of a temperature of 35 DEG C, a humidity of 40%, a voltage difference of 18kV, a needle head aperture of 20G of the electrospinning needle, a distance between the needle head and the receiving plate of 15cm and a speed of the injection pump of 1ml / h, the fiber spinning solution is stretched and accumulated into a nanofiber membrane by the action of electric field force.

[0105] (III) cleaning and removing the pore-forming agent

[0106] The nanofiber membrane obtained in step (II) is soaked in deionized water, and after being cleaned with deionized water, it is dried to obtain a porous antibacterial nanofiber membrane with bifunctional synergistic adsorption of uranium.

[0107] The soaking time is 12h, and the drying conditions are a temperature of 55 DEG C and a drying time of 12h.

[0108] Principle of the application:

[0109] 1. Synthesis route of amidoxime-based oximation solution

[0110]

[0111] The amine nitrogen and oxime oxygen in the amidoxime group can be chelated with the uranyl ion in [UO2(CO3)3] to exhibit high complexing ability. 4-

[0112] 2. Synthesis route of polyaminophosphoric acid:

[0113]

[0114] The abundant amino phosphoric acid groups on the polyaminophosphoric acid have high affinity for uranyl ions, which helps to effectively adsorb and separate by synergistic coordination chelation.

[0115] ​The present application prepares polyaminophosphonic acid and amidoxime which can coordinate and efficiently adsorb uranium by a simple synthesis method, forms nanofiber membranes by electrospinning of water-soluble pore-forming agent, raw material amidoxime and polyaminophosphonic acid together, removes water-soluble pore-forming agent by soaking the prepared multifunctional nanofiber membranes in water to achieve the purpose of adjusting the pore structure of the fiber surface, forms porous structure high specific surface area antibacterial type double functional group structure nanofiber membranes for synergistic adsorption of uranium, increases the specific surface area of nanofiber to double the adsorption effect of the fiber, and the abundant amidoxime groups and polyaminophosphonic acid groups on the multifunctional nanofiber synergistically act on the enrichment of uranium in seawater uranium extraction and the treatment of uraniumyl ions in industrial wastewater, and the special antibacterial effect of the amino phosphoric acid group can reduce the adhesion of microorganisms and plants and animals in the water body to the adsorbent, thereby affecting the adsorption effect of the adsorption material and causing damage and failure of the adsorption material, improving the adsorption effect of uranium and protecting the adsorption material.

[0116] The present application applies electrospinning technology and combines phase separation technology to apply the prepared porous antibacterial uranium adsorption nanofiber to the field of seawater uranium extraction and wastewater treatment, which can effectively improve the adsorption effect of the material and reduce the interference effect of microorganisms in the water body, and at the same time, helps to realize the development and utilization of waste textile fibers, and has important practical significance for the development of new environment-friendly high-efficiency adsorbents and efficient adsorption of seawater uranium extraction.

[0117] The multifunctional antibacterial uranium adsorption nanofiber with a porous structure of the present application is prepared by a green and simple one-step synthesis method, and the raw materials with adsorption and antibacterial effects are prepared, then the two kinds of functional group raw materials are fully dissolved according to a certain proportion, polyvinylpyrrolidone with good water solubility and stable electrospinning performance is selected as a nanofiber surface pore-forming agent, the two are mixed according to a certain proportion to prepare a polymer solution with a certain mass fraction, and the polymer solution is stretched and accumulated into nanofibers under the action of an electric field force by using a simple and economical electrospinning technology under suitable conditions and parameters, and finally the water-soluble pore-forming agent is removed to form nanofibers with a porous structure. The large specific surface area and efficient double functional groups improve the adsorption capacity of the material to low-concentration uranium in water, and the composition of the raw material can also effectively inhibit the interference of water microorganisms on the adsorption process and the damage to the adsorption material, and can be used as a seawater uranium extraction material with excellent performance to help uranium enrichment work to a certain extent.

[0118] The applicant declares that the above description is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed by the present application can be easily thought of by those skilled in the art in the technical field, and fall within the protection scope and disclosure scope of the present application.

Claims

1. A method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, characterized in that: Includes the following steps: (I) Preparation of fiber spinning solution Add the oxime, polyaminophosphoric acid and pore-forming agent to the solvent in sequence, mix and stir to obtain the nanofiber spinning solution; The mass ratio of the methylamine oxime, polyaminophosphate, and pore-forming agent is (2.5–4):5:(3–4); The mass-to-volume ratio of the methine oxime to the solvent is 1:(8-12); The mass fraction of polyaminophosphoric acid in the nanofiber spinning solution is 8% to 15%. The stirring time in step (Ⅰ) is 20h to 26h; (II) Preparation of nanofiber membranes by electrospinning technology The fiber spinning solution prepared in step (I) is stretched and stacked into a nanofiber membrane by electrospinning technology using an electric field. (III) Cleaning and removing pore-forming agent The nanofiber membrane obtained in step (II) is immersed in deionized water, then washed with deionized water and dried to obtain a nanofiber membrane with a porous structure that is antibacterial and has dual functional groups that synergistically adsorb uranium.

2. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, according to claim 1, is characterized in that: The pore-forming agent is polyvinylpyrrolidone; the solvent is N,N'-dimethylformamide.

3. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, as described in claim 1, is characterized in that: The specific operation of step (II) electrospinning technology is as follows: the fiber spinning solution prepared in step (I) is placed into a 10ml syringe. Under the conditions of a temperature of 35℃~39℃, a humidity of 30%~50%, a voltage difference of 16kV~18kV, an electrospinning needle aperture of 20G, a needle distance of 15cm~20cm from the receiving plate, and an injection pump speed of 0.8ml / h~1.5ml / h, the fiber spinning solution is stretched and stacked into a nanofiber membrane by the action of an electric field.

4. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, as described in claim 1, is characterized in that: The soaking time in step (III) is 12h to 18h; the drying conditions are: temperature of 55℃ to 65℃, drying time of 10h to 12h.

5. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, according to claim 1, is characterized in that: The preparation method of the aforementioned amygdoxime includes the following steps: (i) Mix hydroxylamine hydrochloride and N,N'-dimethylformamide, and after the hydroxylamine hydrochloride is completely dissolved, add sodium hydroxide and stir vigorously. (ii) Add polyacrylonitrile powder to the solution in step (i), stir until the polyacrylonitrile is completely swollen, heat and continue stirring until the reaction is complete, centrifuge to obtain the supernatant, which is the amine oxime spinning solution; (iii) The oxime spinning solution from step (ii) was injected into methanol using a syringe to obtain a white granular precipitate; (iv) Wash and dry the white granular precipitate obtained in step (iii) to obtain amygdoxime.

6. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, according to claim 5, is characterized in that: The mass ratio of hydroxylamine hydrochloride to N,N'-dimethylformamide is (2.5-4):25; the mass ratio of sodium hydroxide to hydroxylamine hydrochloride is (20-26):40; and the mass ratio of polyacrylonitrile to hydroxylamine hydrochloride is (16-19):

25.

7. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption, according to claim 1, is characterized in that: The preparation method of the polyaminophosphoric acid includes the following steps: (i) After stirring the solid phosphorous acid into a liquid state, add polyacrylonitrile powder to it and continue stirring until the polyacrylonitrile is fully swollen to obtain a yellowish-brown thick liquid; (ii) The yellowish-brown viscous liquid obtained in step (i) is injected into deionized water through a syringe, and a pale yellow solid is precipitated. After separation, washing and drying, polyaminophosphoric acid is obtained.

8. The method for preparing a porous, antibacterial, bifunctional nanofiber membrane for synergistic uranium adsorption according to claim 7, characterized in that: The mass ratio of the solid phosphorous acid to polyacrylonitrile is (8-15):

1.

9. A nanofiber membrane with a porous structure that is antibacterial and exhibits synergistic adsorption of uranium by dual functional groups, characterized in that: Prepared by the method described in any one of claims 1 to 8.

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