A kind of nanocomposite environment-friendly adsorption material and preparation method, regeneration method and application

Abstract

The present application relates to a kind of nanocomposite environmental protection adsorption material and preparation method, regeneration method and application, it is related to adsorption material technical field.The preparation method of the present application first compounding, by suspension polymerization, chloromethylation, amination modification and post-processing etc. steps are prepared to nanocomposite environmental protection adsorption material according to specific proportion of framework raw material, functional modifier, pore former, initiator and auxiliary reagent.The preparation process of the present application is environmental protection, and the nanocomposite environmental protection adsorption material of easy industrialization production is prepared 131 I ion adsorption selectivity, high adsorption capacity, excellent radiation stability, can be reused, reduce processing cost, suitable for radiology 131 I pollutant efficient treatment, with significant practical value and environmental benefits, solve the existing anion exchange resin to radiology 131 I ion adsorption selectivity, low adsorption capacity, insufficient radiation stability, and easily interfered by coexisting anion.

Description

Technical Field

[0001] This invention relates to the field of adsorption materials technology, specifically to a nanocomposite environmentally friendly adsorption material, its preparation method, regeneration method, and applications. Background Technology

[0002] 131 I is an artificial radionuclide with a half-life of 8.02 days. It is highly radioactive and mainly used in the diagnosis and treatment of thyroid diseases in radiology departments. 131 During the storage, use, and disposal of I, substances containing... 131 I ion (I - The direct discharge of radioactive wastewater and exhaust gases from [unspecified source] poses a serious threat to the ecological environment and human health, especially [unspecified]. 131 I-1 tends to accumulate in the human thyroid gland, causing thyroid diseases. Therefore, it is important for radiology departments to take precautions. 131 The efficient adsorption and removal of I ions is a key step in the remediation of radioactive pollution.

[0003] Currently used for adsorption 131 Materials for adsorbing I-ion mainly include inorganic adsorbents and organic ion exchange resins. Inorganic adsorbents, such as zeolite and activated carbon, while low in cost, have poor adsorption selectivity, are easily interfered with by coexisting anions such as sulfate and nitrate in wastewater, and have low adsorption capacity, making them unsuitable for low-concentration applications in radiology departments. 131 The need for advanced treatment of I- ions. Traditional anion exchange resins such as 201×7Cl and 251×8Cl... - Type, although it can adsorb 131 I ions, but for 131 I- ions have poor selectivity and radiation stability, and are prone to structural damage in the strong radiation environment of radiology departments, resulting in decreased adsorption performance. At the same time, their regeneration performance is poor, and the long-term use cost is high.

[0004] In the existing technology, some patents and research have attempted to modify anion exchange resins to improve their performance. 131 The adsorption performance of I- ions. For example, some studies have used silver-modified zeolite for adsorption. 131 Ion exchange resins are available, but silver is expensive and prone to shedding, causing secondary pollution. Other studies have explored the preparation of anion exchange resins through amination modification of polystyrene-divinylbenzene copolymers, but the modification process is complex and has adverse effects on... 131 The selectivity and radiation stability of I- ions still need to be improved. Furthermore, the chloromethyl ether used in traditional chloromethylation processes is carcinogenic and does not meet environmental protection and safety production requirements, necessitating an environmentally friendly and mild alternative preparation process. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a nanocomposite environmentally friendly adsorbent material, its preparation method, regeneration method, and applications. The preparation process of this invention is environmentally friendly and easily industrialized, resulting in a nanocomposite environmentally friendly adsorbent material with... 131 I-ion adsorption exhibits high selectivity, high adsorption capacity, and excellent radiation stability. It is reusable, reducing processing costs, and is suitable for radiology departments. 131 The efficient treatment of pollutants I has significant practical value and environmental benefits.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: The first objective of this invention is to provide a method for preparing a nanocomposite environmentally friendly adsorbent material, comprising the following steps: (1) Mix the skeleton monomer, crosslinking agent, functional modifier and pore-forming agent evenly, and disperse them by ultrasonication to obtain a first oil phase mixture; add the dispersing stabilizer to water, heat and stir until completely dissolved to obtain an aqueous solution; add the initiator to the first oil phase mixture, stir until completely dissolved to obtain a second oil phase mixture; (2) The second oil phase mixture is slowly added to the aqueous phase solution, and the temperature is raised to 75℃~90℃ under stirring for isothermal polymerization. After the polymerization is completed, the temperature is lowered to room temperature to obtain cross-linked polystyrene white balls. (3) Add the cross-linked polystyrene white balls to the catalyst, stir evenly, slowly add chloromethylating agent to carry out chloromethylation reaction, then wash until neutral, filter and dry to obtain chloromethylated resin; (4) Add an amination reagent to the chloromethylated resin to carry out an amination modification reaction. When the exchange capacity of the product resin obtained by the reaction reaches 1.8 mmol / g to 2.5 mmol / g, add a terminator to terminate the reaction and obtain crude resin. (5) The crude resin is washed until neutral, then soaked in hydrochloric acid solution to transform it into chloride-type ion exchange resin. It is washed again until neutral, and then filtered, dried and sieved to obtain nanocomposite environmentally friendly adsorbent material.

[0007] The beneficial effects of this invention are as follows: The preparation method of this invention first combines framework raw materials, functional modifiers, pore-forming agents, initiators, and auxiliary reagents in a specific ratio, and then prepares nanocomposite environmentally friendly adsorbent materials through suspension polymerization, chloromethylation, amination modification, and post-treatment. The preparation process of this invention is environmentally friendly and easily industrialized, resulting in nanocomposite environmentally friendly adsorbent materials that... 131 Ion adsorption exhibits high selectivity, high adsorption capacity, and excellent radiation stability. It is reusable, reducing processing costs, and is suitable for radiology departments. 131The efficient treatment of I pollutants has significant practical value and environmental benefits, solving the problems of poor selectivity, low adsorption capacity, insufficient radiation stability, and susceptibility to interference from coexisting anions in existing anion exchange resins for radioactive I31I ions.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Furthermore, the heating and stirring rate in step (1) is 50 r / min to 80 r / min.

[0010] Further, in step (1), the mass ratio of the skeleton monomer, the crosslinking agent, the functional modifier, the porogen, and the initiator is 40~60:5~15:8~20:10~25:0.5~3; The mass ratio of the dispersant stabilizer to the water is 2~8:80~150; The skeletal monomer includes at least one of styrene and methylstyrene; the crosslinking agent includes at least one of divinylbenzene and dimethyldivinylbenzene; the functional modifier is at least one of hydrated bismuth trioxide, hydrated zirconium oxide, and aluminum-magnesium composite oxide; the pore-forming agent is at least one of kerosene, toluene, and paraffin; the initiator is at least one of benzoyl peroxide and azobisisobutyronitrile; and the dispersing stabilizer is at least one of polyvinyl alcohol and gelatin. The ultrasonic dispersion time in step (1) is 20 min to 40 min, and the power is 200 W to 300 W; the heating is specifically heating to 40 °C to 60 °C.

[0011] Furthermore, the purity of the skeleton monomer is ≥98%, which ensures the smooth progress of the polymerization reaction and the formation of a structurally stable resin skeleton.

[0012] Furthermore, the purity of the crosslinking agent is ≥98%.

[0013] The beneficial effects of adopting the above-mentioned further solutions are: the addition of crosslinking agents can improve the mechanical strength and chemical stability of the resin, and prevent the resin from breaking down during adsorption and desorption. Divinylbenzene can significantly increase the degree of crosslinking of the resin and enhance its radiation stability. The addition of functional modifiers can significantly improve the resin's resistance to radiation. 131 The selective adsorption capacity of I- ions is evident, with hydrated bismuth oxide (III) and hydrated zirconium oxide exhibiting extremely strong affinity for iodide ions, and can interact with... 131 I- ions form stable complexes, enhancing the resin's radiation stability and preventing structural degradation under strong radiation. Aluminum-magnesium composite oxides further improve the resin's adsorption capacity and mechanical strength, while pore-forming agents create a uniform pore structure within the resin, increasing its specific surface area. 131I- ions provide more adsorption sites and improve adsorption efficiency; kerosene and toluene have excellent pore-forming effects, forming large-pore structures with uniform pore size, while paraffin can adjust pore size and adapt to various conditions. 131 The adsorption requirement of I- ions and the addition of initiators can start the polymerization reaction and control the rate of polymerization. Benzoyl peroxide is suitable for medium and high temperature polymerization, while azobisisobutyronitrile is suitable for medium and low temperature polymerization. The use of both in combination can optimize the polymerization effect and improve the uniformity of the resin skeleton. Dispersing stabilizers can make the oil phase mixture uniformly dispersed in the aqueous phase, avoid particle agglomeration during polymerization, and ensure the uniformity of resin particles. Polyvinyl alcohol has a better dispersion effect than gelatin and can improve the roundness of resin particles.

[0014] Furthermore, the particle size of the functional modifier is 50nm~200nm, and the specific surface area is ≥100m². 2 / g.

[0015] The beneficial effect of adopting the above-mentioned further solutions is that it can enhance the material's resistance to... 131 Selective adsorption capacity and radiation stability of I ions.

[0016] Furthermore, in step (2), the stirring speed is 200 r / min to 400 r / min; the heating rate is 5℃ / min to 10℃ / min; the isothermal polymerization time is 4h to 8h; and the stirring speed is increased by 50 r / min every 1h during this period.

[0017] The advantages of adopting the above-mentioned further scheme are: ensuring uniform polymerization reaction and avoiding uneven resin particle size; slow heating can avoid local overheating that could lead to resin particle agglomeration or uneven structure.

[0018] Further, in step (3), the mass ratio of the cross-linked polystyrene white spheres, the catalyst, and the chloromethylating agent is 1:0.08~0.15:1.2~1.8; the catalyst is at least one of anhydrous zinc chloride and ferric chloride; the chloromethylating agent is at least one of 1,4-dichloromethoxybutane, chloromethyl ether, and dichlorodimethyl ether. The dropping rate in step (3) is 0.05 mL / s to 0.1 mL / s; the stirring speed is 150 r / min to 250 r / min; the chloromethylation reaction is specifically carried out by heating to 30℃ to 50℃ and reacting at a constant temperature for 6 h to 10 h.

[0019] The beneficial effects of adopting the above-mentioned further scheme are: the catalyst can accelerate the chloromethylation and amination reactions, reduce the reaction temperature, shorten the reaction time, and improve the reaction efficiency. Among them, anhydrous zinc chloride has a better catalytic effect and can reduce the occurrence of side reactions; the limited dropping rate can avoid excessively rapid dropping rate leading to violent local reactions. The isothermal reaction allows chloromethyl (-CH2Cl) to be uniformly grafted onto the resin backbone.

[0020] Furthermore, the chloromethylating agent is 1,4-dichloromethoxybutane.

[0021] The beneficial effects of adopting the above-mentioned further scheme are: this step uses 1,4-dichloromethoxybutane to replace the traditional carcinogenic chloromethyl ether, which reduces the safety risks in the production process, is more environmentally friendly, and can reduce the damage to resin performance caused by secondary crosslinking of methylene groups.

[0022] Furthermore, in step (4), the mass ratio of the chloromethylated resin and the amination reagent is 1:1~1.5; The mass ratio of the terminator to the chloromethylated resin is 0.1%~0.5%:1; The amination agent is at least one of trimethylamine and triethylamine; the terminator is one of hydroquinone and tert-butylhydroquinone. The amination modification reaction was carried out at a temperature of 40℃ to 60℃ for 8 hours to 12 hours, and the stirring speed was 150 r / min to 250 r / min.

[0023] Furthermore, the amination agent is trimethylamine, which can enhance the resin's resistance to... 131 Exchange efficiency of I ions.

[0024] The beneficial effect of adopting the above-mentioned further scheme is that, in the amination reaction, the chloromethyl group undergoes a substitution reaction with the amination reagent, introducing a quaternary ammonium group (-N). + (CH3)3Cl - The quaternary ammonium group can interact with 131I ions (I) through ion exchange. - Combined, to achieve 131 The adsorption of I- ions is crucial; therefore, the content of quaternary ammonium groups directly determines the adsorption performance of the resin. By controlling the reaction time and temperature, the grafting rate of quaternary ammonium groups can be ensured, thereby improving the resin's adsorption capacity. 131The adsorption capacity of I- ions. The ratio of amination reagent to chloromethylated resin ensures the amination reaction proceeds fully, allowing sufficient chloromethyl groups to be grafted onto the resin surface. This provides ample active sites for subsequent amination reactions, avoiding resource waste due to excessive amination reagent or excessively low quaternary ammonium group grafting rate due to insufficient amination reagent. Trimethylamine has higher amination efficiency than triethylamine, significantly improving the resin's exchange capacity and adsorption rate. Terminators can promptly terminate the polymerization and amination reactions, preventing over-reaction and resin structure damage, thus ensuring resin performance stability. Furthermore, uniform stirring ensures uniform concentration in the reaction system, improving reaction efficiency and resin performance stability.

[0025] Furthermore, when the terminator is hydroquinone, its addition amount is preferably 0.25% to 0.5% of the mass of the chloromethylated resin; when the terminator is tert-butylhydroquinone, its addition amount is preferably 0.1% to 0.3% of the mass of the chloromethylated resin.

[0026] Furthermore, the drying method in step (5) is vacuum drying, the temperature is 60℃~80℃, and the time is 4h~6h; the concentration of the hydrochloric acid solution is 1mol / L, and the soaking time is 1.5h~4h.

[0027] The beneficial effect of adopting the above further scheme is: the resin is transformed into Cl. - Type, easy to use 131 I ion (I - Ion exchange occurs.

[0028] Furthermore, the sieving in step (5) uses a standard sieve, and the resulting nanocomposite environmentally friendly adsorbent material is resin particles of 40-60 mesh.

[0029] The advantages of adopting the above-mentioned further scheme are: ensuring uniform resin particles, and 40-60 mesh resin particles can ensure good fluid permeability, avoid clogging the adsorption column, and at the same time take into account adsorption efficiency and mechanical strength.

[0030] The second objective of this invention is to provide a nanocomposite environmentally friendly adsorbent material.

[0031] The beneficial effects of this invention are: the nanocomposite environmentally friendly adsorbent material of this invention has the following effects: 131 The adsorption capacity of I ions is ≥1.8 mmol / g, and the adsorption rate is ≥99.5%. This is achieved under gamma ray irradiation doses ≤10... 5 Under Gy conditions, the exchange capacity retention rate is ≥95%, and it can be regenerated by 50 mL of 1 mol / L hydrochloric acid solution at a flow rate of 1 mL / min with a regeneration rate of ≥98%. After five consecutive regenerations, the adsorption performance shows no significant decay.

[0032] The third objective of this invention is to provide an application of a nanocomposite environmentally friendly adsorbent material, wherein the nanocomposite environmentally friendly adsorbent material is used for... 131 In the treatment of pollutants I.

[0033] The beneficial effects of this invention are: the nanocomposite environmentally friendly adsorbent material prepared by this invention is suitable for radiology departments. 131 Radioactive wastewater and exhaust gas generated during the diagnosis and treatment process 131 Highly efficient adsorption treatment of I ions.

[0034] The fourth objective of this invention is to provide a method for regenerating nanocomposite environmentally friendly adsorbent materials, comprising the following steps: (1) Using water for saturated adsorption 131 The nanocomposite environmentally friendly adsorbent material for pollutant I was backwashed at a flow rate of 2 BV / h to 4 BV / h and a washing time of 15 min to 30 min to obtain the backwashed nanocomposite environmentally friendly adsorbent material. (2) Fix the backwashed nanocomposite environmentally friendly adsorbent material onto the adsorption purification bed, and regenerant passes through the adsorption purification bed in the forward direction at a flow rate of 1 BV / h~2 BV / h to regenerate the nanocomposite environmentally friendly adsorbent material after preliminary regeneration. (3) After regeneration, rinse with water until the pH of the effluent is 6-8 and the conductivity is ≤100 μS / cm; then use 1BV-2BV of 3% hydrochloric acid solution for transformation, and finally rinse until neutral. The amount of the regenerant used is 3BV~5BV; the regenerant is a sodium chloride solution with a mass fraction of 3%~5%, or a mixed solution of sodium hydroxide with a mass fraction of 1%~2% and sodium chloride with a mass fraction of 3% at pH=11~13.

[0035] The fifth objective of this invention is to provide the regenerated nanocomposite environmentally friendly adsorbent material obtained by the aforementioned regeneration method in... 131 Applications of I pollutants in treatment. Detailed Implementation

[0036] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0037] Example 1: Preparation of Nanocomposite Environmentally Friendly Adsorbent Material (1) Raw material pretreatment and mixing: 40 parts by mass of styrene, 5 parts by mass of divinylbenzene, 8 parts by mass of hydrated bismuth oxide (III) and 10 parts by mass of kerosene were mixed evenly and ultrasonically dispersed for 20 min at an ultrasonic power of 200 W to obtain the first oil phase mixture; 2 parts by mass of polyvinyl alcohol were added to 80 parts by mass of deionized water, heated to 40°C, and stirred at a stirring rate of 50 r / min to 80 r / min until completely dissolved to obtain an aqueous solution; 0.5 parts by mass of benzoyl peroxide were added to the first oil phase mixture and stirred until completely dissolved to obtain the second oil phase mixture for later use; (2) Suspension polymerization: The second oil phase mixture was slowly added to the aqueous phase solution, the stirring speed was adjusted to 200 r / min, the temperature was raised to 75℃ at a heating rate of 5℃ / min, and the polymerization was carried out at a constant temperature for 4h. During this period, the stirring speed was increased by 50 r / min every 1h. After the polymerization was completed, the temperature was lowered to room temperature to obtain cross-linked polystyrene white balls. (3) Chloromethylation reaction: Add cross-linked polystyrene white balls to the reaction vessel, add 1 part by mass of anhydrous zinc chloride, stir evenly, slowly add 1,4-dichloromethoxybutane (mass ratio of cross-linked polystyrene white balls is 1.2:1), control the dropping rate to 1 drop / second, after the dropping is completed, raise the temperature to 30℃, and react at a constant temperature for 6h. After the reaction is completed, wash with deionized water until neutral, filter and dry to obtain chloromethylated resin; (4) Amination modification: Chloromethylated resin was added to the reaction vessel, and 15 parts by mass of trimethylamine (with a mass ratio of 1:1 to chloromethylated resin) were added. The reaction temperature was controlled at 40℃, the stirring speed was 150r / min, and the reaction was stirred for 8h. During the reaction, samples were taken every 2h. When the resin exchange capacity reached 1.8mmol / g, 0.1 parts by mass of hydroquinone was added to terminate the reaction and crude resin was obtained. (5) Post-treatment: The crude resin was washed with deionized water until neutral, and then soaked in 1 mol / L hydrochloric acid solution for 2 hours to convert it into Cl. - The sample is then washed with deionized water until neutral, filtered, vacuum dried at 60°C for 4 hours, and sieved to obtain 40-60 mesh target anion exchange resin particles, which are the nanocomposite environmentally friendly adsorbent materials.

[0038] Example 2: Preparation of Nanocomposite Environmentally Friendly Adsorbent Material II (1) Raw material pretreatment and mixing: 60 parts by mass of methylstyrene, 15 parts by mass of dimethyldivinylbenzene, 20 parts by mass of hydrated zirconium oxide and 25 parts by mass of toluene were mixed evenly and ultrasonically dispersed for 40 min at an ultrasonic power of 300 W to obtain the first oil phase mixture; 8 parts by mass of gelatin were added to 150 parts by mass of deionized water, heated to 60℃, and stirred at a stirring rate of 50 r / min to 80 r / min until completely dissolved to obtain an aqueous solution; 3 parts by mass of azobisisobutyronitrile were added to the first oil phase mixture and stirred until completely dissolved to obtain the second oil phase mixture for later use; (2) Suspension polymerization: The second oil phase mixture was slowly added to the aqueous phase solution, the stirring speed was adjusted to 400 r / min, the temperature was raised to 90℃ at a heating rate of 10℃ / min, and the polymerization was carried out at a constant temperature for 8 hours. During this period, the stirring speed was increased by 50 r / min every 1 hour. After the polymerization was completed, the temperature was lowered to room temperature to obtain cross-linked polystyrene white balls. (3) Chloromethylation reaction: Add cross-linked polystyrene white balls to the reaction vessel, add 5 parts by mass of ferric chloride, stir evenly, slowly add 1,4-dichloromethoxybutane (mass ratio of cross-linked polystyrene white balls is 1.8:1), control the dropping rate to 2 drops / second, after the dropping is completed, raise the temperature to 50℃, and react at a constant temperature for 10h. After the reaction is completed, wash with deionized water until neutral, filter and dry to obtain chloromethylated resin; (4) Amination modification: Chloromethylated resin was added to the reaction vessel, and 30 parts by mass of triethylamine (the mass ratio of triethylamine to chloromethylated resin was 1.5:1) was added. The reaction temperature was controlled at 60℃, the stirring speed was 250r / min, and the reaction was stirred for 12h. During this period, samples were taken every 2h for testing. When the resin exchange capacity reached 2.5mmol / g, 1 part by mass of tert-butylhydroquinone was added to terminate the reaction and crude resin was obtained. (5) Post-treatment: The crude resin was washed with deionized water until neutral, and then soaked in 1 mol / L hydrochloric acid solution for 2 hours to convert it into Cl. - The sample is then washed with deionized water until neutral, filtered, vacuum dried at 80℃ for 6 hours, and sieved to obtain 40~60 mesh target anion exchange resin particles, which are nanocomposite environmentally friendly adsorbent materials.

[0039] Example 3: Preparation of Nanocomposite Environmentally Friendly Adsorbent Materials (1) Raw material pretreatment and mixing: Mix 50 parts by weight of styrene, 10 parts by weight of divinylbenzene, 14 parts by weight of functional modifier (a mixture of hydrated bismuth oxide (III) and aluminum magnesium composite oxide, with a mass ratio of 1:1) and 18 parts by weight of paraffin wax evenly, and ultrasonically disperse for 30 min with an ultrasonic power of 250 W; add 5 parts by weight of dispersion stabilizer (a mixture of polyvinyl alcohol and gelatin with a mass ratio of 1:1) to 110 parts by weight of deionized water, heat to 50°C, and stir at a stirring rate of 50 r / min to 80 r / min until completely dissolved to obtain an aqueous phase solution; add 1.8 parts by weight of initiator (a mixture of benzoyl peroxide and azobisisobutyronitrile with a mass ratio of 1:1) to the second oil phase mixture and stir until completely dissolved for later use; (2) Suspension polymerization: The second oil phase mixture was slowly added to the aqueous phase solution, the stirring speed was adjusted to 300 r / min, the temperature was increased to 82℃ at a heating rate of 8℃ / min, and the polymerization was carried out at a constant temperature for 6 hours. During this period, the stirring speed was increased by 50 r / min every 1 hour. After the polymerization was completed, the temperature was lowered to room temperature to obtain cross-linked polystyrene white balls. (3) Chloromethylation reaction: Cross-linked polystyrene white balls were added to the reaction vessel, and 3 parts by mass of catalyst (a mixture of anhydrous zinc chloride and ferric chloride in a mass ratio of 1:1) were added. The mixture was stirred evenly, and 1,4-dichloromethoxybutane (in a mass ratio of 1.5:1 to the cross-linked polystyrene white balls) was slowly added dropwise. The dropping rate was controlled at 1.5 drops / second. After the addition was completed, the temperature was raised to 40°C and the reaction was kept constant for 8 hours. After the reaction was completed, the mixture was washed with deionized water until neutral, filtered, and dried to obtain chloromethylated resin. (4) Amination modification: Chloromethylated resin was added to a reaction vessel, and 22 parts by mass of amination reagent (a mixture of trimethylamine and triethylamine in a mass ratio of 1:1; the mass ratio of the reagent to the chloromethylated resin was 1.2:1) was added. The reaction temperature was controlled at 50℃, the stirring speed was 200r / min, and the reaction was stirred for 10h. Samples were taken every 2h during the reaction. When the resin exchange capacity reached 2.2mmol / g, 0.5 parts by mass of hydroquinone was added to terminate the reaction and crude resin was obtained. (5) Post-treatment: The crude resin was washed with deionized water until neutral, and then soaked in 1 mol / L hydrochloric acid solution for 2 hours to convert it into Cl. - The sample is then washed with deionized water until neutral, filtered, vacuum dried at 70℃ for 5 hours, and sieved to obtain 40~60 mesh target anion exchange resin particles, which are nanocomposite environmentally friendly adsorbent materials.

[0040] Example 4: Regeneration of Nanocomposite Environmentally Friendly Adsorbent Materials (1) Use deionized water for saturated adsorption 131The nanocomposite environmentally friendly adsorbent material of Example 1 for pollutant I was backwashed at a flow rate of 3 BV / h for 23 min to remove suspended impurities and loose pollutants from the surface of the adsorbent material and the bed. (2) A sodium chloride solution with a mass fraction of 4% was used as a regenerator and passed through the adsorption purification bed at a flow rate of 1 BV / h. The amount of regenerator used was 4 BV. (3) After regeneration, rinse the resin with deionized water until the pH of the effluent is 7 and the conductivity is ≤100μS / cm; then use 2BV of 3% hydrochloric acid solution for transformation, and finally rinse until neutral.

[0041] Example 5: Regeneration of Nanocomposite Environmentally Friendly Adsorbent Materials (1) Use deionized water for saturated adsorption 131 The nanocomposite environmentally friendly adsorbent material of Example 2 for pollutant I was backwashed at a flow rate of 2 BV / h for 30 min to remove suspended impurities and loose pollutants from the surface of the adsorbent material and the bed. (2) A 5% sodium chloride solution was used as a regenerator and passed through the adsorption purification bed at a flow rate of 1 BV / h. The amount of regenerator was 3 BV. (3) After regeneration, rinse the resin with deionized water until the pH of the effluent is 8 and the conductivity is ≤100μS / cm; then transform it with 2BV of 3% hydrochloric acid solution, and finally rinse until neutral.

[0042] Example 6: Regeneration of Nanocomposite Environmentally Friendly Adsorbent Materials (1) Use deionized water for saturated adsorption 131 The nanocomposite environmentally friendly adsorbent material of Example 3 for pollutant I was backwashed at a flow rate of 4 BV / h for 15 min to remove suspended impurities and loose pollutants from the surface of the adsorbent material and the bed. (2) A mixed solution of 1%~2% sodium hydroxide and 3% sodium chloride (pH=11~13) was used as the regenerator and passed through the adsorption purification bed at a flow rate of 2BV / h. The amount of regenerator was 5BV. Enhanced regeneration was carried out. (3) After regeneration, rinse the resin with deionized water until the pH of the effluent is 6 and the conductivity is ≤100μS / cm; then use 2BV of 3% hydrochloric acid solution for transformation, and finally rinse until neutral.

[0043] Comparative Example 1: Commercially available 201×7Cl type anion exchange resin Comparative Example 2: Preparation of Resin without Functional Modifier The only difference between this comparative example and Example 3 is that the functional modifier in step (1) of Example 3 was not added to this comparative example. The other raw material types, ratios, and preparation processes are exactly the same as those in Example 3.

[0044] Comparative Example 3: Preparation of Resin for Chloromethyl Ether Process The only difference between this comparative example and Example 3 is that the environmentally friendly 1,4-dichloromethoxybutane in Example 3 is replaced with chloromethyl ether in equal amounts. The other raw material types, ratios, and preparation processes are exactly the same as in Example 3.

[0045] Performance testing: Take 0.5g of commercially available 201×7 Cl-type anion exchange resin from Comparative Example 1, 0.5g of resin without functional modifier from Comparative Example 2, 0.5g of chloromethyl ether process resin from Comparative Example 3, and 0.5g of resin prepared in Examples 1-3 of this invention, and conduct the following comparative experiments under the same conditions: (1) 131 I. Adsorption performance test: Under the conditions of 25℃ and pH=6~7, each group of resins was mixed with... 131 I. Initial solution was mixed and adsorbed by isothermal shaking at 180 r / min for 12 h until equilibrium was reached. Residual liquid phase was detected using a high-purity germanium gamma spectrometer. 131 I content, calculated to obtain the resin's effect 131 Equilibrium adsorption capacity and adsorption rate of I ions; Equilibrium adsorption capacity: Adsorption rate: Where: qe is the equilibrium adsorption capacity (mg / g or mmol / g); C0 is... 131 I. Initial solution concentration; C e For the liquid phase after adsorption equilibrium 131 I is the residual concentration; V is the volume of the adsorption solution; m is the dry weight of the resin used; η is the adsorption rate.

[0046] (2) Irradiation stability test: using 60 A Co-γ ray source was used to apply a total dose of 10 to each group of resins under ambient air conditions. 5 By irradiating Gy, the saturated exchange capacity of the resin before and after irradiation was compared to obtain the exchange capacity retention rate after irradiation. Resin saturated exchange capacity: In the formula: Q—saturated exchange capacity of resin, mmol / g; —Concentration of standard silver nitrate solution consumed in titration, mmol / mL; —The volume of standard silver nitrate solution consumed by the resin to leach out all iodide ions, in mL; —The mass of dry resin used in the test, in grams.

[0047] Switching capacity retention rate: In the formula: R—Retention rate of exchange capacity after irradiation, % —Saturated exchange capacity of resin before irradiation test, mmol / g; —Resin after 10 5 Gy 60 Saturated exchange capacity after Co γ-ray irradiation, mmol / g.

[0048] (3) Single regeneration performance test: The resins of each group that were saturated with adsorption were statically soaked in 1 mol / L hydrochloric acid solution for 4 hours. After being washed and neutralized with water, the adsorption capacity was retested to obtain the regeneration rate. (4) Cyclic stability test: The adsorption process was continuously cyclically operated 5 times according to the unified adsorption 1mol / L hydrochloric acid regeneration process. The adsorption performance was retested after each regeneration. After 5 consecutive regenerations, the adsorption rate was still above 99.2%.

[0049] exist 131 At an initial I-ion concentration of 10 mg / L, adsorption was performed using 0.5 g of resin from Example 1 and 0.5 g of resin from Comparative Example 1, respectively. The adsorption temperature was 25 °C, the adsorption time was 2 h, and the gamma ray irradiation dose was 10 mg / L. 5 The adsorption properties of the two resins were tested using Gy, and the results are shown in Table 1 below: Table 1 As shown in Table 1: The anion exchange resin materials prepared in Examples 1-3 of this invention exhibit excellent performance in terms of adsorption capacity, adsorption rate, radiation stability, and regeneration rate. Compared to the commercially available conventional resin in Comparative Example 1 and the values ​​prepared in Comparative Examples 2 and 3, the anion exchange resin material in Example 1 demonstrates superior performance in terms of adsorption capacity, adsorption rate, radiation stability, and regeneration rate. 131 The adsorption capacity of I- ions was 1.8 mmol / g, with an adsorption rate of 99.5%. Under γ-ray irradiation at a dose of 105 Gy, the exchange capacity retention rate was 95%. After regeneration with 1 mol / L hydrochloric acid solution, the regeneration rate was 98.2%. After five consecutive regenerations, the adsorption rate remained above 99.0%. The anion exchange resin material of Example 2... 131 The adsorption capacity of I ions is 2.5 mmol / g, and the adsorption rate is 99.8%. This is achieved under γ-ray irradiation at a dose of 10... 5Under Gy conditions, the exchange capacity retention rate was 97%, and after regeneration with 1 mol / L hydrochloric acid solution, the regeneration rate was 98.8%. After five consecutive regenerations, the adsorption rate remained above 99.2%. Example 3 showed an adsorption capacity of 2.2 mmol / g and an adsorption rate of 99.7%. After irradiation, the exchange capacity retention rate was still as high as 96.0%, and the regeneration rate was 98.5%. All performance indicators were significantly better than those of Comparative Examples 1, 2, and 3, proving that the formulation and process of this invention effectively improve the adsorption capacity, radiation resistance stability, and recyclability of the resin, and can be efficiently applied to radioactive wastewater treatment scenarios.

[0050] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a nanocomposite environmentally friendly adsorbent material, characterized in that, Includes the following steps: (1) Mix the skeleton monomer, crosslinking agent, functional modifier and pore-forming agent evenly, and disperse them by ultrasonication to obtain a first oil phase mixture; add the dispersing stabilizer to water, heat and stir until completely dissolved to obtain an aqueous solution; add the initiator to the first oil phase mixture, stir until completely dissolved to obtain a second oil phase mixture; (2) The second oil phase mixture is slowly added to the aqueous phase solution, and the temperature is raised to 75~90℃ under stirring for isothermal polymerization. After the polymerization is completed, the temperature is lowered to room temperature to obtain cross-linked polystyrene white balls. (3) Add the cross-linked polystyrene white balls to the catalyst, stir evenly, slowly add chloromethylating agent to carry out chloromethylation reaction, then wash until neutral, filter and dry to obtain chloromethylated resin; (4) Add an amination reagent to the chloromethylated resin to carry out an amination modification reaction. When the exchange capacity of the product resin obtained by the reaction reaches 1.8 mmol / g to 2.5 mmol / g, add a terminator to terminate the reaction and obtain crude resin. (5) The crude resin is washed until neutral, then soaked in hydrochloric acid solution to transform it into chloride-type ion exchange resin. It is washed again until neutral, and then filtered, dried and sieved to obtain nanocomposite environmentally friendly adsorbent material.

2. The method for preparing a nanocomposite environmentally friendly adsorbent material according to claim 1, characterized in that, The mass ratio of the skeleton monomer, the crosslinking agent, the functional modifier, the porogen, and the initiator in step (1) is 40~60:5~15:8~20:10~25:0.5~3; The mass ratio of the dispersant stabilizer to the water is 2~8:80~150; The skeletal monomer includes at least one of styrene and methylstyrene; the crosslinking agent includes at least one of divinylbenzene and dimethyldivinylbenzene; the functional modifier is at least one of hydrated bismuth trioxide, hydrated zirconium oxide, and aluminum-magnesium composite oxide; the pore-forming agent is at least one of kerosene, toluene, and paraffin; the initiator is at least one of benzoyl peroxide and azobisisobutyronitrile; and the dispersing stabilizer is at least one of polyvinyl alcohol and gelatin. The ultrasonic dispersion time in step (1) is 20 min to 40 min, and the power is 200 W to 300 W; the heating is specifically heating to 40 °C to 60 °C.

3. The method for preparing a nanocomposite environmentally friendly adsorbent material according to claim 1, characterized in that, In step (2), the stirring speed is 200 r / min to 400 r / min; the heating rate is 5℃ / min to 10℃ / min; the isothermal polymerization time is 4h to 8h; and the stirring speed is increased by 50 r / min every 1h during this period.

4. The method for preparing a nanocomposite environmentally friendly adsorbent material according to claim 1, characterized in that, In step (3), the mass ratio of the cross-linked polystyrene white spheres, the catalyst, and the chloromethylating agent is 1:0.08~0.15:1.2~1.8; the catalyst is at least one of anhydrous zinc chloride and ferric chloride; the chloromethylating agent is at least one of 1,4-dichloromethoxybutane, chloromethyl ether, and dichlorodimethyl ether. The dropping rate in step (3) is 0.05 mL / s to 0.1 mL / s; the stirring speed is 150 r / min to 250 r / min; the chloromethylation reaction is specifically carried out by heating to 30℃ to 50℃ and reacting at a constant temperature for 6 h to 10 h.

5. The method for preparing a nanocomposite environmentally friendly adsorbent material according to claim 1, characterized in that, In step (4), the mass ratio of the chloromethylated resin and the amination reagent is 1:1~1.5; The mass ratio of the terminator to the chloromethylated resin is 0.1% to 0.5%. The amination agent is at least one of trimethylamine and triethylamine; the terminator is one of hydroquinone and tert-butylhydroquinone. The amination modification reaction was carried out at a temperature of 40℃ to 60℃ for 8 hours to 12 hours, and the stirring speed was 150 r / min to 250 r / min.

6. The method for preparing a nanocomposite environmentally friendly adsorbent material according to claim 1, characterized in that, The drying method in step (5) is vacuum drying, the temperature is 60℃~80℃, and the time is 4h~6h; the concentration of the hydrochloric acid solution is 0.8mol / L~1.4mol / L, and the soaking time is 1.5h~4h.

7. A nanocomposite environmentally friendly adsorbent material, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 6.

8. An application of a nanocomposite environmentally friendly adsorbent material, characterized in that, The nanocomposite environmentally friendly adsorbent material according to claim 9 is used for 131 In the treatment of pollutants I.

9. A method for regenerating a nanocomposite environmentally friendly adsorbent material, characterized in that, Includes the following steps: (1) Using water for saturated adsorption 131 The nanocomposite environmentally friendly adsorbent material for pollutant I was backwashed at a flow rate of 2 BV / h to 4 BV / h and a washing time of 15 min to 30 min to obtain the backwashed nanocomposite environmentally friendly adsorbent material. (2) Fix the backwashed nanocomposite environmentally friendly adsorbent material onto the adsorption purification bed, and regenerant passes through the adsorption purification bed in the forward direction at a flow rate of 1 BV / h~2 BV / h to regenerate the nanocomposite environmentally friendly adsorbent material after preliminary regeneration. (3) After regeneration, rinse with water until the pH of the effluent is 6-8 and the conductivity is ≤100 μS / cm; then use 1BV-2BV of 3% hydrochloric acid solution for transformation, and finally rinse until neutral. The amount of the regenerant used is 3BV~5BV; the regenerant is a sodium chloride solution with a mass fraction of 3%~5%, or a mixed solution of sodium hydroxide with a mass fraction of 1%~2% and sodium chloride with a mass fraction of 3% at pH=11~13.

10. The regenerated nanocomposite environmentally friendly adsorbent material obtained based on the regeneration method described in claim 9, in... 131 Applications of I pollutants in treatment.

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