A resin material and its preparation and application

Abstract

The present invention relates to the technical field of actinide separation and adsorption materials, and in particular to a resin material, its preparation, and application. The present invention first prepares polystyrene resin beads through a suspension polymerization method. These beads are then modified using N,N-dioctane-2-hydroxyacetamide via a Williamson ether synthesis reaction to produce a special resin material with excellent adsorption properties for americium under high acid conditions. This material can be used in research on plutonium and americium separation technology. The present invention has the advantages of a simple and efficient preparation process, low cost, and ease of industrial application.

Description

Technical Field

[0001] The present invention relates to the technical field of actinide separation and adsorption materials, in particular to a resin material and its preparation and application. Background Art

[0002] With the continuous expansion of nuclear power units, nuclear power plants generate a large amount of spent fuel, and human nuclear activities such as emissions from spent fuel reprocessing plants and nuclear accidents generate about 6.4×10 12 Bq americium ( 241 Am) is released into the environment, causing the global alpha radioactivity level produced by transuranium elements to increase, and the issue of environmental radioactivity safety assessment is prominent. 241 Pu) decay daughters, americium ( 241 Am) will be along with high activity plutonium ( 241 The decay of Pu) has been increasing and has become the main α radioactive pollutant. Americium (Am) is mainly present in the environment as AmCO 3+ 、AmSO 4+ 、Am 3+ It migrates in other forms and enters the human body through the food chain, further accumulating in bones, liver, and muscles. It stays in the body for a long time, irradiating human organs and tissues, causing short-term and long-term effects. Even when the dose in the tissue is quite low, it may cause malignant tumors, and it is difficult to promote excretion and treat.

[0003] Treatment of spent fuel for the removal of radioactive americium not only reduces the pollution and harm of radionuclides to the environment and humans, but also allows for the recycling and reuse of americium, improving resource utilization. The main methods for separating americium and plutonium include chemical precipitation, ion exchange, adsorption, and extraction, with ion exchange being the most commonly used. The ion exchange method achieves the separation of americium and plutonium by utilizing the difference in the interaction between the special functional groups in the ion exchange resin and americium and plutonium. This method is simple to operate, has good selectivity, and has broad application prospects. One of the core elements of ion exchange resins is the selection of functional groups. Based on the characteristics of the radioactive element americium, it is crucial to design a resin material that can selectively separate americium and provide a new key material for americium-plutonium separation research. Summary of the Invention

[0004] To address the above-mentioned issues, the present invention provides a resin material, its preparation, and its application. The present invention first prepares polystyrene resin beads through a suspension polymerization method. These beads are then modified through an N,N-dioctane-2-hydroxyacetamide Williamson ether synthesis reaction to produce a special resin material with excellent adsorption of americium under high-concentration nitric acid conditions. This material can be used in research on plutonium and americium separation technology.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The first object of the present invention is to provide a resin material, wherein the polymer skeleton molecular structure of the resin material is as shown in formula (I),

[0007]

[0008] Here, n is a positive integer ranging from 500 to 1000.

[0009] A second object of the present invention is to provide a method for preparing a resin material, comprising the following steps:

[0010] (S1) mixing the oil phase and the water phase and performing suspension polymerization, and then post-processing to obtain white balls;

[0011] (S2) placing the white ball prepared in step (S1) in dichloromethane to swell, mixing with chloromethyl ether and a catalyst, and reacting, and performing post-treatment after the reaction to obtain a chloromethylated modified white ball;

[0012] (S3) swelling the chloromethylated modified white ball obtained in step (S2) in N,N-dimethylformamide, and subjecting the swollen chloromethylated modified white ball to a Williamson ether synthesis reaction with a product of the reaction of N,N-dialkyl-hydroxyacetamide and sodium to obtain a resin material;

[0013] Wherein, the aqueous phase is a mixed solution of dispersant and sodium chloride;

[0014] The oil phase is a mixed solution of styrene, a cross-linking agent, an initiator and a porogen.

[0015] In one embodiment of the present invention, the dispersant is selected from one or more of gelatin, polyvinyl alcohol, lignin or kaolin;

[0016] The cross-linking agent is selected from one of divinylbenzene, melamine or trimethylolpropane trimethacrylate;

[0017] The initiator is selected from one or both of benzoyl peroxide and azobisisobutyronitrile;

[0018] The porogen is selected from one of acetone, toluene, isooctane, linear polystyrene, liquid paraffin or cyclohexane.

[0019] In one embodiment of the present invention, the mass ratio of dispersant to sodium chloride is 0.5-2:5-20;

[0020] The mass ratio of styrene, cross-linking agent, initiator and porogen is 95:5-10:1-2:20-60.

[0021] In one embodiment of the present invention, in step (S1), the mass ratio of the water phase to the oil phase is 4 to 5:1.

[0022] In one embodiment of the present invention, in step (S1), the suspension polymerization reaction process includes a resin microsphere forming process and a microsphere curing reaction process;

[0023] During the resin microsphere molding process, the temperature is 63°C to 75°C and the time is 16h to 24h;

[0024] During the microsphere curing reaction, the temperature is 80°C to 90°C and the time is 8 to 16 hours.

[0025] In one embodiment of the present invention, in step (S1), the post-treatment is filtration, washing, removal of porogen and subsequent drying.

[0026] In one embodiment of the present invention, in step (S2), the ratio of dichloromethane, chloromethyl ether, catalyst and white ball is 1mL: 5mL-6mL: 0.4g-0.7g: 1g;

[0027] During the reaction, the temperature is 50°C and the reaction time is 24h to 26h.

[0028] In one embodiment of the present invention, in step (S2), the post-treatment is washing to neutrality after filtration.

[0029] In one embodiment of the present invention, in step (S3), the mass ratio of N,N-dialkyl-hydroxyacetamide, sodium and chloromethylated modified white balls is 13-14:1.35-3:3-3.5.

[0030] In one embodiment of the present invention, in step (S3), during the reaction of N,N-dialkyl-hydroxyacetamide with sodium, the temperature is 38° C. and the time is 10 h to 12 h;

[0031] During the Williamson ether synthesis reaction, the temperature is 160°C to 170°C and the reaction time is 52h to 72h.

[0032] The third object of the present invention is to provide an application of a resin material in the separation of plutonium and americium.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) This invention discloses for the first time a resin material for the separation of americium and plutonium and its preparation method. The material preparation method is divided into three steps: resin white ball synthesis, chloromethylation modification, and Williamson modification experiment, and finally synthesizes an amide ether-containing resin microsphere material.

[0035] (2) The present invention has the advantages of simple and efficient preparation process, low cost, and easy industrial promotion and application.

[0036] (3) The resin material prepared by the present invention has a significant adsorption effect on americium under 7.2 mol / L nitric acid conditions, with an adsorption capacity of 2.34 mmol / g, but a poor adsorption effect on plutonium, with an adsorption capacity of less than 0.6 mmol / g; and has a significant adsorption effect on plutonium under 0.9 mol / L nitric acid system, with an adsorption capacity of 2.40 mmol / g, but a poor adsorption effect on americium. DETAILED DESCRIPTION

[0037] The present invention provides a resin material, wherein the polymer skeleton molecular structure of the resin material is as shown in formula (I),

[0038]

[0039] Here, n is a positive integer ranging from 500 to 1000.

[0040] The present invention provides a method for preparing a resin material, comprising the following steps:

[0041] (S1) mixing the oil phase and the water phase and performing suspension polymerization, and then post-processing to obtain white balls;

[0042] (S2) placing the white ball prepared in step (S1) in dichloromethane to swell, mixing with chloromethyl ether and a catalyst, and reacting, and performing post-treatment after the reaction to obtain a chloromethylated modified white ball;

[0043] (S3) swelling the chloromethylated modified white ball obtained in step (S2) in N,N-dimethylformamide, and subjecting the swollen chloromethylated modified white ball to a Williamson ether synthesis reaction with a product of the reaction of N,N-dialkyl-hydroxyacetamide and sodium to obtain a resin material;

[0044] Wherein, the aqueous phase is a mixed solution of dispersant and sodium chloride;

[0045] The oil phase is a mixed solution of styrene, a cross-linking agent, an initiator and a porogen.

[0046] In one embodiment of the present invention, the dispersant is selected from one or more of gelatin, polyvinyl alcohol, lignin or kaolin;

[0047] The cross-linking agent is selected from one of divinylbenzene, melamine or trimethylolpropane trimethacrylate;

[0048] The initiator is selected from one or both of benzoyl peroxide and azobisisobutyronitrile;

[0049] The porogen is selected from one of acetone, toluene, isooctane, linear polystyrene, liquid paraffin or cyclohexane.

[0050] In one embodiment of the present invention, the mass ratio of dispersant to sodium chloride is 0.5-2:5-20;

[0051] The mass ratio of styrene, cross-linking agent, initiator and porogen is 95:5-10:1-2:20-60.

[0052] In one embodiment of the present invention, in step (S1), the mass ratio of the water phase to the oil phase is 4 to 5:1.

[0053] In one embodiment of the present invention, in step (S1), the suspension polymerization reaction process includes a resin microsphere forming process and a microsphere curing reaction process;

[0054] During the resin microsphere molding process, the temperature is 63°C to 75°C and the time is 16h to 24h;

[0055] During the microsphere curing reaction, the temperature is 80°C to 90°C and the time is 8 to 16 hours.

[0056] In one embodiment of the present invention, in step (S1), the post-treatment is filtration, washing, removal of porogen and subsequent drying.

[0057] In one embodiment of the present invention, in step (S2), the ratio of dichloromethane, chloromethyl ether, catalyst and white ball is 1mL: 5mL-6mL: 0.4g-0.7g: 1g;

[0058] During the reaction, the temperature is 50°C and the reaction time is 24h to 26h.

[0059] In one embodiment of the present invention, in step (S2), the post-treatment is washing to neutrality after filtration.

[0060] In one embodiment of the present invention, in step (S3), the mass ratio of N,N-dialkyl-hydroxyacetamide, sodium and chloromethylated modified white balls is 13-14:1.35-3:3-3.5.

[0061] In one embodiment of the present invention, in step (S3), during the reaction of N,N-dialkyl-hydroxyacetamide with sodium, the temperature is 38° C. and the time is 10 h to 12 h;

[0062] During the Williamson ether synthesis reaction, the temperature is 160°C to 170°C and the reaction time is 52h to 72h.

[0063] The present invention provides an application of a resin material in the separation of plutonium and americium.

[0064] The present invention is described in detail below with reference to specific embodiments.

[0065] In the following examples, unless otherwise specified, all reagents used are commercially available reagents, and all detection and methods used are conventional detection means and methods in the art.

[0066] Example 1

[0067] This embodiment provides a resin material and a preparation method thereof.

[0068] (1) Preparation of white balls by monomer polymerization

[0069] Prepare the aqueous phase: Add 60.0 g of sodium chloride, 5.0 g of gelatin, and 3.0 g of kaolin into a 1.0 L three-necked round-bottom flask, measure 500 mL of water, add it to the flask, and stir until all the solids are dissolved.

[0070] Prepare the oil phase: Add 90.0 g of styrene monomer, 10.0 g of divinylbenzene (cross-linker), 1.0 g of benzoyl peroxide (initiator), and 40.0 g of toluene (porogen) into a 300 mL beaker and mix and stir until all the solids are dissolved.

[0071] Polymerization reaction: The oil phase and the water phase are mixed and added to the reaction vessel, the mechanical stirring speed is adjusted, and the temperature is slowly increased at a rate of 5°C / min to carry out suspension polymerization reaction (including the resin microsphere molding process and the microsphere curing reaction process);

[0072] Start polymerization at 73°C (for the resin microsphere molding process) and keep the reaction at a constant temperature for 2 hours. When the solidified microspheres can be deposited (for the microsphere curing reaction process), raise the temperature to 85°C at one time and keep it warm for 14 hours. After the reaction is completed, filter the reactants and wash the white balls with hot water until the filtrate changes from turbid to clear. Then transfer the white balls to a flat-bottom flask, add an appropriate amount of water and boil for 5 hours. After boiling, filter and wash the white balls with ethanol to remove the porogen. Heat to 70°C in a vacuum oven and dry for 24 hours to obtain white balls. The reaction process and the molecular structure of the white ball polymer skeleton are as follows:

[0073] n is a positive integer from 500 to 1000.

[0074] (2) Chloromethylation modification of white balls

[0075] Take 20g of the white ball prepared in step (1), add 20mL of dichloroethane to swell for 2.0h, add 110mL of chloromethyl ether and 13.0g of ZnCl2 (catalyst), raise the temperature to 50°C, and react for 24h. After the reaction is completed, filter out the reaction solution and wash with water until neutral to obtain chloromethylated white ball. The molecular structure of the chloromethylated white ball polymer skeleton is as follows:

[0076] n is a positive integer from 500 to 1000.

[0077] (3) Williamson ether synthesis reaction modification

[0078] Take 20 g of the chloromethylated modified white ball prepared in step (2), add 10 mL of N,N-dimethylformamide and fully swell for 4 h;

[0079] 1.85 g of sodium metal and 13.5 g of N,N-dialkyl-hydroxyacetamide were added to the reactor and reacted for 10 h at a temperature below 38° C. After the reaction, Williamson ether synthesis reaction was carried out with the swollen chloromethylated modified white ball. The reaction temperature was controlled at 168° C. and the reaction was carried out for 52 h to obtain a resin material. The molecular structure of the polymer skeleton of the resin material is as follows:

[0080] n is a positive integer from 500 to 1000.

[0081] Example 2

[0082] This embodiment provides a resin material and a preparation method thereof.

[0083] (1) Preparation of white balls by monomer polymerization

[0084] Prepare the aqueous phase: Add 25.0 g of sodium chloride and 3.0 g of polyvinyl alcohol to a 500 mL three-necked round-bottom flask, measure 250 mL of water and add it to the flask, and stir until all the solids are dissolved.

[0085] Prepare the oil phase: Add 60.0 g of styrene monomer, 6.0 g of ethylene glycol dimethacrylate (cross-linker), 1.2 g of azobisisobutyronitrile (initiator), and 30.0 g of toluene (porogen) into a 300 mL beaker and mix and stir until all the solids are dissolved.

[0086] Polymerization reaction: The oil phase and the water phase are mixed and added to the reaction vessel, the mechanical stirring speed is adjusted, and the temperature is slowly increased at a rate of 5°C / min to carry out suspension polymerization reaction (including the resin microsphere molding process and the microsphere curing reaction process);

[0087] Polymerization begins at 64°C (the resin microsphere molding process) and is maintained at this temperature for 2 hours. When the solidified microspheres are ready for deposition (the microsphere curing reaction process), the temperature is raised to 80°C and maintained for 10 hours. After the reaction is complete, the reactants are filtered and the white microspheres are washed with hot water until the filtrate turns clear from turbidity. The white microspheres are then transferred to a flat-bottom flask, boiled with an appropriate amount of water, and held for 5 hours. After boiling, the mixture is filtered and washed with ethanol to remove the porogen. The microspheres are then dried in a vacuum oven at 70°C for 24 hours to obtain the white microspheres.

[0088] (2) Chloromethylation modification of white balls

[0089] Take 20g of the white ball prepared in step (1), add 20mL of dichloroethane to swell for 2.0h, add 120mL of chloromethyl ether and 14g of ZnCl2 (catalyst), raise the temperature to 50℃, and react for 24h. After the reaction is completed, filter out the reaction solution and wash with water until neutral to obtain chloromethylated modified white ball.

[0090] (3) Williamson ether synthesis reaction modification

[0091] Take 20 g of the chloromethylated modified white ball prepared in step (2), add 10 mL of N,N-dimethylformamide and fully swell for 4 h;

[0092] 2 g of sodium metal and 13.47 g of N,N-dialkyl-hydroxyacetamide were added to the reactor and reacted for 10 h at a temperature below 38 ° C. After the reaction, Williamson ether synthesis reaction was carried out with the swollen chloromethylated modified white ball. The reaction temperature was controlled at 170 ° C. and the reaction was carried out for 72 h to obtain a resin material.

[0093] Example 3

[0094] This embodiment provides an adsorption performance test for a resin material.

[0095] (1) Pretreatment of resin materials

[0096] The resin material prepared in Example 1 was rinsed six times with 70°C hot water, then washed seven times with a mixture of ethanol, and then rinsed with deionized water until the ethanol was removed. The washed resin material was soaked in deionized water for 48 hours, and then soaked in 7.0 mol / L nitric acid (4 times the volume of the resin material) for 4 hours.

[0097] (2) Resin adsorption process

[0098] Prepare americium nitrate solution with a concentration of 289 mg / L and a nitric acid concentration of 7.2 mol / L;

[0099] Prepare plutonium nitrate solution with a concentration of 261 mg / L and nitric acid concentration of 7.2 mol / L;

[0100] Weigh 0.25 g of the resin material pretreated in step (1) and add it to 6 wide-mouth bottles respectively. Add 25 mL of americium nitrate solution to 3 of the wide-mouth bottles, and add 25 mL of plutonium nitrate solution to the other 3 wide-mouth bottles. Mix them evenly, place them on a shaker for adsorption at room temperature for 48 hours, and take samples to measure the concentration using a graphite crystal diffraction analyzer.

[0101] Prepare an americium nitrate solution with a concentration of 289 mg / L and a nitric acid concentration of 0.9 mol / L respectively; prepare a plutonium nitrate solution with a concentration of 261 mg / L and a nitric acid concentration of 0.9 mol / L respectively; otherwise, conduct an adsorption performance test, and then take samples to analyze the plutonium and americium concentrations.

[0102] (3) Result analysis

[0103] The resin material has a significant adsorption effect on americium under 7.2 mol / L nitric acid conditions, with an adsorption capacity of 2.34 mmol / g, but has a poor adsorption effect on plutonium, with an adsorption capacity of less than 0.6 mmol / g.

[0104] In the 0.9 mol / L nitric acid system, it has a significant adsorption effect on plutonium with an adsorption capacity of 2.40 mmol / g, but has a poor adsorption effect on americium.

[0105] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the explanations of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A resin material, characterized in that: The polymer skeleton molecular structure of the resin material is shown in formula (I), Here, n is a positive integer ranging from 500 to 1000.

2. A method for preparing a resin material according to claim 1, characterized in that: The following steps are involved: (S1) mixing the oil phase and the water phase and performing suspension polymerization, and then post-processing to obtain white balls; (S2) placing the white ball prepared in step (S1) in dichloromethane to swell, mixing with chloromethyl ether and a catalyst, and reacting, and performing post-treatment after the reaction to obtain a chloromethylated modified white ball; (S3) swelling the chloromethylated modified white ball obtained in step (S2) in N,N-dimethylformamide, and subjecting the swollen chloromethylated modified white ball to a Williamson ether synthesis reaction with a product of the reaction of N,N-dialkyl-hydroxyacetamide and sodium to obtain a resin material; Wherein, the aqueous phase is a mixed solution of dispersant and sodium chloride; The oil phase is a mixed solution of styrene, a cross-linking agent, an initiator and a porogen.

3. The method for preparing a resin material according to claim 2, wherein: The dispersant is selected from one or more of gelatin, polyvinyl alcohol, lignin or kaolin; The cross-linking agent is selected from one of divinylbenzene, melamine or trimethylolpropane trimethacrylate; The initiator is selected from one or both of benzoyl peroxide and azobisisobutyronitrile; The porogen is selected from one of acetone, toluene, isooctane, linear polystyrene, liquid paraffin or cyclohexane.

4. The method for preparing a resin material according to claim 2, wherein: The mass ratio of dispersant to sodium chloride is 0.5-2:5-20; The mass ratio of styrene, cross-linking agent, initiator and porogen is 95:5-10:1-2:20-60.

5. The method for preparing a resin material according to claim 2, wherein: In step (S1), the mass ratio of the water phase to the oil phase is 4 to 5:

1.

6. The method for preparing a resin material according to claim 2, wherein: In step (S1), the suspension polymerization reaction process includes a resin microsphere forming process and a microsphere curing reaction process; During the resin microsphere molding process, the temperature is 63°C to 75°C and the time is 16h to 24h; During the microsphere curing reaction, the temperature is 80°C to 90°C and the time is 8 to 16 hours.

7. The method for preparing a resin material according to claim 2, wherein: In step (S2), the ratio of dichloromethane, chloromethyl ether, catalyst and white ball is 1mL:5mL-6mL:0.4g-0.7g:1g; During the reaction, the temperature is 50°C and the reaction time is 24h to 26h.

8. The method for preparing a resin material according to claim 2, wherein: In step (S3), the mass ratio of N,N-dialkyl-hydroxyacetamide, sodium and chloromethylated modified white balls is 13-14:1.35-3:3-3.

5.

9. The method for preparing a resin material according to claim 2, wherein: In step (S3), during the reaction of N,N-dialkyl-hydroxyacetamide and sodium, the temperature is 38° C. and the reaction time is 10 h to 12 h; During the Williamson ether synthesis reaction, the temperature is 160°C to 170°C and the reaction time is 52h to 72h.

10. Use of the resin material according to claim 1 in the separation of plutonium and americium.

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