Nuclear-grade ion exchange resin-based composite material as well as preparation method and application thereof

Abstract

The invention discloses a nuclear-grade ion exchange resin-based composite material as well as a preparation method and application thereof, and belongs to the technical field of nuclear-grade ion exchange resin preparation in the nuclear industry. The nuclear-grade ion exchange resin-based composite material is prepared by carrying out purification, secondary quaternization and transformation on an anion exchange resin composite material; the anion exchange resin composite material is prepared by quaternizing and transforming a chloromethylated ion exchange resin composite material; the chloromethylated ion exchange resin composite material is prepared by carrying out white ball swelling and chloromethylation on the ion exchange resin composite material; the ion exchange resin composite material white ball is prepared by suspension polymerization of styrene, divinyl benzene and 5-vinyl-2, 2 '-dipyridyl intercalated magnesium-aluminum bimetal hydroxide under the action of an initiator. The composite material has the advantages of high surface purity and mechanical strength, excellent ion exchange capacity and transformation rate, and good chemical and radiation resistance stability.

Description

Technical Field

[0001] The invention relates to a material and a preparation method thereof, in particular to a nuclear-grade ion exchange resin-based composite material and a preparation method and application thereof, belonging to the technical field of nuclear-grade ion exchange resin preparation in the nuclear industry. Background Art

[0002] With the continuous growth of global energy demand and the increasing awareness of environmental protection, nuclear energy, as a clean and efficient form of energy, is increasingly widely used in fields such as power generation. In the fields of nuclear power plants and nuclear waste treatment, ion exchange resins are widely used to remove radioactive ions (such as cesium, strontium, cobalt, etc.) from water. Traditional ion exchange resins are prone to degradation in strong radiation environments, resulting in a decrease in exchange capacity and mechanical strength, affecting their service life and performance. It is necessary to develop nuclear-grade ion exchange resins with excellent chemical stability, radiation resistance, ion exchange capacity and mechanical strength to ensure stable operation under extreme conditions, thereby ensuring the safe operation of nuclear facilities and the proper treatment of nuclear waste.

[0003] Chinese patent ZL 201710998181.5 discloses a core-shell structure composite material based on a nuclear-grade ion exchange resin and a preparation method thereof, wherein the core-shell structure composite material has a light rare earth oxide such as cerium oxide, lanthanum oxide or praseodymium oxide as a core and a nuclear-grade strong alkaline anion exchange resin as a shell. The light rare earth metal oxide has excellent radiation resistance and chemical stability, thereby improving the stability of the nuclear-grade ion exchange resin when used in the nuclear industry. However, light rare earth oxides such as cerium oxide, lanthanum oxide or praseodymium oxide are easy to migrate in the pores of the ion exchange resin, thereby affecting the exchange capacity of the ion exchange resin. Chinese patent ZL 202310588493.4 discloses a preparation method for a nuclear-grade cation exchange resin, wherein polystyrene is introduced into the resin during the preparation process, and polystyrene is interspersed in the formed polymer in the suspension polymerization reaction. During the swelling process, polystyrene is dissolved by ethylene dichloride, thereby forming pores inside the white ball, thereby increasing the sulfonation rate and the specific surface area of ​​the cation exchange resin. However, polystyrene dissolves in the white spheres to form pores, which greatly reduces the mechanical strength of the cation exchange resin, causing the resin to break during use. Therefore, it is of great significance to prepare a nuclear-grade ion exchange resin with excellent performance. Summary of the invention

[0004] Purpose of the invention: To solve the problems existing in the prior art, a nuclear-grade ion exchange resin-based composite material is provided, which has high surface purity and mechanical strength, excellent ion exchange capacity and transformation rate, and good chemical resistance and radiation stability.

[0005] At the same time, the present invention provides a method for preparing a nuclear-grade ion exchange resin-based composite material.

[0006] At the same time, the present invention provides an application of a nuclear-grade ion exchange resin-based composite material.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] A nuclear-grade ion exchange resin-based composite material is prepared by purifying, secondary quaternizing and transforming an anion exchange resin composite material; the anion exchange resin composite material is prepared by quaternizing and transforming a chloromethylated ion exchange resin composite material; the chloromethylated ion exchange resin composite material is prepared by swelling and chloromethylating white spheres of the ion exchange resin composite material; the white spheres of the ion exchange resin composite material are prepared by suspension polymerization of styrene, divinylbenzene and 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double metal hydroxide under the action of an initiator; and the 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double metal hydroxide is prepared by a hydrothermal method.

[0009] Furthermore, the preparation method of the nuclear-grade ion exchange resin-based composite material comprises the following steps:

[0010] Step 1), purifying polyvinyl pyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, aluminum salt, magnesium salt, precipitant, styrene, divinylbenzene, initiator, ethylene dichloride, chloromethyl ether, trimethylamine, Na2CO3, acetone, deionized water, and anhydrous methanol;

[0011] The purification method is an existing general method, and the purification method includes the following contents: deionized water is mainly distilled and adsorbed; low-boiling point organic matter is distilled and precisely filtered; high-boiling point organic matter is vacuum distilled and precisely filtered; inorganic matter is mainly recrystallized, zone melting and precisely filtered.

[0012] After purification, it is guaranteed that the impurity content of polyvinyl pyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, aluminum salt, magnesium salt, precipitant, styrene, divinylbenzene, initiator, dichloroethane, chloromethyl ether, trimethylamine, Na2CO3, acetone and anhydrous methanol is less than 1ppm after purification, and the deionized water reaches 18 mega high-purity water after purification.

[0013] Step 2), at room temperature, polyvinyl pyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, deionized water, and anhydrous methanol are added to a reactor, ultrasonically stirred for 0.5 to 2 hours, aluminum salt and magnesium salt are continuously added to the reactor under stirring, and ultrasonic stirring is continued for 0.5 to 2 hours after the magnesium salt and aluminum salt are completely dissolved, and a precipitant is continuously added to the reactor, and a hydrothermal reaction is carried out at 130 to 180° C. for 3 to 6 hours, and the reaction is cooled to room temperature and filtered, and the filter cake is alternately washed with anhydrous methanol and deionized water until the pH of the washing liquid reaches 7, and dried at 80 to 120° C. for 10 to 24 hours to obtain a magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine;

[0014] Step 3), at room temperature, under nitrogen protection, styrene, divinylbenzene, 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide and initiator are stirred evenly, heated to 60-90° C., reacted for 2-5 hours, cooled to room temperature and filtered, the filter cake is washed alternately with anhydrous methanol and deionized water, vacuum dried at 60-80° C. for 12-24 hours, and sieved to obtain ion exchange resin composite white balls;

[0015] Step 4), at room temperature, adding the ion exchange resin composite material white ball into dichloroethane, stirring and swelling for 1 to 2 hours, then adding chloromethyl ether, continuing the reaction at 40 to 50° C. for 10 to 12 hours, cooling to room temperature, and filtering to obtain the chloromethylated ion exchange resin composite material;

[0016] Step 5), at room temperature, adding the chloromethylated ion exchange resin composite material to a 30-40% trimethylamine aqueous solution, adjusting the pH of the mixed solution to 8-10 using a 1-1.5 mol / L Na2CO3 aqueous solution, stirring the reaction at 110-120° C. for 10-12 hours, cooling to room temperature, and filtering to obtain an anion exchange resin composite material;

[0017] Step 6), at room temperature, ultrasonically soak the anion exchange resin composite material in acetone for 12 to 24 hours, filter out the acetone and load it into a washing column, wash it with deionized water, 30 to 40% trimethylamine aqueous solution, 1 to 1.5 mol / L Na2CO3 aqueous solution, and deionized water in sequence, and vacuum dry it at 60 to 80° C. for 12 to 24 hours to prepare a nuclear-grade ion exchange resin-based composite material.

[0018] Furthermore, in step 1), the aluminum salt is selected from aluminum nitrate or aluminum isopropoxide, the magnesium salt is selected from magnesium nitrate or magnesium acetate, the precipitant is selected from ammonia water or sodium hydroxide, and the initiator is selected from cyclohexanone peroxide or diisobutyl peroxydicarbonate.

[0019] Further, in step 2), the mass ratio of deionized water: anhydrous methanol: polyvinyl pyrrolidone: citric acid: 5-vinyl-2,2'-bipyridine: precipitant: magnesium salt: aluminum salt is (20-50): (20-50): (0.01-0.05): (0.01-0.1): (0.3-1): (0.2-2): (0.8-2): 1; wherein the mass ratio of deionized water: anhydrous methanol is 1:1;

[0020] Further, in step 3), the mass ratio of divinylbenzene: 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide: initiator: styrene is (0.08-0.18): (0.01-0.05):

[0021] (0.03~0.05):1.

[0022] Furthermore, in step 4), the volume mass ratio of dichloroethane: ion exchange resin composite material white balls is (10-20): 1, in units of mL / g; the volume mass ratio of chloromethyl ether: ion exchange resin composite material white balls is (3-5): 1, in units of mL / g.

[0023] Furthermore, in step 5), the volume mass ratio of 30-40% trimethylamine aqueous solution: chloromethylated ion exchange resin composite material is (3-5):1, in units of mL / g; and the stirring rate is 50-100 rpm.

[0024] Furthermore, in step 6), the volume mass ratio of acetone: anion exchange resin composite material is (2-4):1, in units of mL / g.

[0025] Further, in step 6), the filling amount of the washing column is 60-80%; the deionized water washing temperature is 50-80°C, the washing temperature of the 30-40% trimethylamine aqueous solution and the 1-1.5 mol / L Na2CO3 aqueous solution is 20-40°C, and the washing method is to pass through the washing column from top to bottom at a speed of 1-2BV / h. The first deionized water washing, 30-40% trimethylamine aqueous solution washing and 1-1.5 mol / L Na2CO3 aqueous solution washing time are all 2-4h, and the endpoint of the second deionized water washing is when the pH of the washing liquid reaches 7.

[0026] Furthermore, in the present invention, all stirring rates are 50-100 rpm; all ultrasonic powers are 100-500W.

[0027] The nuclear-grade ion exchange resin-based composite material of the present invention has an average crushing strength of ≥350g / particle, a transformation rate of ≥94%, a volume exchange capacity of ≥1.3eq / L, and Cl - Content ≤0.2%, SO42- Content ≤0.2%, CO3 2- Content ≤4.3%, organic extractables ≤0.09%.

[0028] The nuclear-grade ion exchange resin-based composite material of the present invention is used in the purification of water in various loops of a nuclear power plant or a nuclear power plant or in the preparation of ultrapure water.

[0029] A nuclear-grade ion exchange device is prepared by using the nuclear-grade ion exchange resin-based composite material of the invention.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention purifies the raw materials used in the preparation process of nuclear-grade ion exchange resin-based composite materials, effectively reduces the occurrence of side reactions during the polymerization reaction of nuclear-grade ion exchange resin-based composite materials, improves the uniformity of the polymerization reaction of nuclear-grade ion exchange resin-based composite materials, ensures the force uniformity of the spheres of nuclear-grade ion exchange resin-based composite materials, and can significantly improve the crushing strength of nuclear-grade ion exchange resin-based composite materials, so that they exhibit excellent high temperature resistance and radiation resistance; at the same time, raw material purification reduces the amount of impurities in the nuclear-grade ion exchange resin-based composite materials, improves the purity of the nuclear-grade ion exchange resin-based composite materials, and further improves the ion exchange capacity and transformation rate of the nuclear-grade ion exchange resin-based composite materials.

[0032] 2. The present invention introduces 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide as the third monomer during the resin polymerization process, which effectively adjusts the competitive polymerization rate of styrene and divinylbenzene, improves the polymerization degree of the styrene skeleton, reduces the generation of low-crosslinked polystyrene fragments, and makes the skeleton of the ion exchange resin composite white ball more uniform, thereby greatly reducing the dissolution of organic solvents in the nuclear-grade ion exchange resin-based composite material; at the same time, a larger volume of 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide is interspersed in the white ball, so that the ion exchange resin composite white ball will produce more pores during the swelling process, thereby improving the specific surface area of ​​the ion exchange resin composite white ball, and enhancing the methylation rate and transformation rate of the ion exchange resin composite white ball, thereby ensuring that the nuclear-grade ion exchange resin-based composite material has a higher ion exchange capacity.

[0033] 3. The present invention adopts 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide as the third monomer, which can effectively improve the dispersibility of magnesium aluminum double hydroxide in nuclear-grade ion exchange resin-based composite materials. The highly dispersed magnesium aluminum double hydroxide can further improve the crushing strength of the nuclear-grade ion exchange resin-based composite materials, making it not easy to break in the nuclear power plant environment and stably operate; at the same time, magnesium aluminum double hydroxide can catalyze the dissociation of chloride ions in the chloromethylated ion exchange resin composite materials, thereby improving the transformation rate of the nuclear-grade ion exchange resin-based composite materials; magnesium aluminum double hydroxide and 5-vinyl-2,2'-bipyridine work together, utilizing the strong nucleophilicity of the nitrogen atom in 5-vinyl-2,2'-bipyridine and the surface alkalinity of magnesium aluminum double hydroxide, which can effectively improve the exchange adsorption capacity of the nuclear-grade ion exchange resin-based composite materials, and further improve the exchange capacity of the nuclear-grade ion exchange resin-based composite materials.

[0034] 4. The present invention can effectively reduce the residual soluble organic matter and impurities in the nuclear-grade ion exchange resin-based composite material by washing and purifying the anion exchange resin composite material with acetone and deionized water, secondary quaternization and transformation treatment, and prepare a nuclear-grade ion exchange resin-based composite material with high purity, large exchange capacity, good stability and large ion exchange capacity. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below in conjunction with specific examples. The following examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0036] The raw materials used in the following examples were all purified. The deionized water was purified to 18 ppm high-purity water, and the impurity content of the remaining raw materials was less than 1 ppm after purification.

[0037] Example 1

[0038] A method for preparing a nuclear-grade ion exchange resin-based composite material comprises the following steps:

[0039] At room temperature, 0.1 g of polyvinyl pyrrolidone, 0.1 g of citric acid, 3 g of 5-vinyl-2,2'-bipyridine, 200 g of deionized water, and 200 g of anhydrous methanol were added to a reactor, and ultrasonic stirring was performed for 0.5 h. Under stirring, 10 g of aluminum nitrate and 8 g of magnesium nitrate were continuously added to the reactor, and ultrasonic stirring was continued for 0.5 h after the magnesium nitrate and aluminum nitrate were completely dissolved. 2 g of sodium hydroxide was continuously added to the reactor, and hydrothermal reaction was performed at 130° C. for 3 h. After cooling to room temperature, the mixture was filtered, and the filter cake was alternately washed with anhydrous methanol and deionized water until the pH of the washing liquid reached 7, and dried at 80° C. for 10 h to obtain a magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine;

[0040] At room temperature, under nitrogen protection, 10 g of styrene, 0.8 g of divinylbenzene, 0.1 g of 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide and 0.3 g of cyclohexanone peroxide were stirred evenly, heated to 60°C, reacted for 2 h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 60°C for 12 h, and ion exchange resin composite white balls were obtained after sieving;

[0041] At room temperature, 10 g of ion exchange resin composite white balls were added to 100 mL of dichloroethane, stirred and swollen for 1 h, and then 30 mL of chloromethyl ether was added. The reaction was continued at 40° C. for 10 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material.

[0042] At room temperature, 10 g of the chloromethylated ion exchange resin composite material was added to 30 mL of a 30% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 8 with a 1 mol / L Na2CO3 aqueous solution. The mixture was stirred at 50 rpm for 10 h at 110° C., cooled to room temperature, and filtered to obtain an anion exchange resin composite material.

[0043] At room temperature, 10 g of anion exchange resin composite material was ultrasonically soaked in 20 mL of acetone for 12 h, and the acetone was filtered out and then loaded into a washing column with a filling capacity of 60%. The anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water, 20°C 30% trimethylamine aqueous solution, and 20°C 1 mol / L Na2CO3 aqueous solution at a speed of 1 BV / h for 2 h, and then the anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water until the pH of the washing liquid was 7, and then vacuum dried at 60°C for 12 h to prepare a nuclear-grade ion exchange resin-based composite material.

[0044] The nuclear-grade ion exchange resin-based composite material is obtained by the preparation method of this embodiment.

[0045] The nuclear-grade ion exchange resin-based composite material of this embodiment is used in the purification of water in various loops of a nuclear power plant or a nuclear power plant or in the preparation of ultrapure water.

[0046] A nuclear-grade ion exchange device is prepared using the nuclear-grade ion exchange resin-based composite material of this embodiment.

[0047] Example 2

[0048] A method for preparing a nuclear-grade ion exchange resin-based composite material comprises the following steps:

[0049] At room temperature, 0.5 g polyvinyl pyrrolidone, 1 g citric acid, 10 g 5-vinyl-2,2'-bipyridine, 500 g deionized water, and 500 g anhydrous methanol were added to a reactor, and ultrasonic stirring was performed for 2 h. Under stirring, 10 g aluminum isopropoxide and 20 g magnesium acetate were continuously added to the reactor, and ultrasonic stirring was continued for 2 h after magnesium acetate and aluminum isopropoxide were completely dissolved. 20 g ammonia water was continuously added to the reactor, and hydrothermal reaction was performed at 180° C. for 6 h. After cooling to room temperature, the reaction mixture was filtered, and the filter cake was alternately washed with anhydrous methanol and deionized water until the pH of the washing solution reached 7, and dried at 120° C. for 24 h to obtain a magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine.

[0050] At room temperature, under nitrogen protection, 10g of styrene, 1.8g of divinylbenzene, 0.5g of 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide and 0.5g of diisobutyl peroxydicarbonate were stirred evenly, heated to 90°C, reacted for 5h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 80°C for 24h, and sieved to obtain ion exchange resin composite white balls;

[0051] At room temperature, 10 g of ion exchange resin composite material white balls were added to 200 mL of dichloroethane, stirred and swollen for 2 h, then 50 mL of chloromethyl ether was added, and the reaction was continued at 50° C. for 12 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material;

[0052] At room temperature, 10 g of the chloromethylated ion exchange resin composite material was added to 50 mL of a 40% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 10 with a 1.5 mol / L Na2CO3 aqueous solution. The mixture was stirred at 100 rpm for 12 h at 120°C, cooled to room temperature, and filtered to obtain an anion exchange resin composite material.

[0053] At room temperature, 10 g of anion exchange resin composite material was ultrasonically soaked in 40 mL of acetone for 24 h, and the acetone was filtered out and then loaded into a washing column with a filling capacity of 80%. The anion exchange resin composite material was washed from top to bottom through the washing column with 80°C deionized water, 40°C 40% trimethylamine aqueous solution, and 40°C 1.5 mol / L Na2CO3 aqueous solution at a speed of 2BV / h for 4 h, and then the anion exchange resin composite material was washed from top to bottom through the washing column with 80°C deionized water until the pH of the washing liquid was 7, and then vacuum dried at 80°C for 24 h to prepare a nuclear-grade ion exchange resin-based composite material.

[0054] The nuclear-grade ion exchange resin-based composite material is obtained by the preparation method of this embodiment.

[0055] The nuclear-grade ion exchange resin-based composite material of this embodiment is used in the purification of water in various loops of a nuclear power plant or a nuclear power plant or in the preparation of ultrapure water.

[0056] A nuclear-grade ion exchange device is prepared using the nuclear-grade ion exchange resin-based composite material of this embodiment.

[0057] Example 3

[0058] A method for preparing a nuclear-grade ion exchange resin-based composite material comprises the following steps:

[0059] At room temperature, 0.3 g of polyvinyl pyrrolidone, 0.5 g of citric acid, 5 g of 5-vinyl-2,2'-bipyridine, 300 g of deionized water, and 300 g of anhydrous methanol were added to a reactor, and ultrasonic stirring was performed for 1 hour. Under stirring, 10 g of aluminum isopropoxide and 10 g of magnesium nitrate were continuously added to the reactor, and ultrasonic stirring was continued for 1 hour after the magnesium nitrate and aluminum isopropoxide were completely dissolved. 10 g of sodium hydroxide was continuously added to the reactor, and hydrothermal reaction was performed at 150° C. for 4 hours. After cooling to room temperature, the mixture was filtered, and the filter cake was alternately washed with anhydrous methanol and deionized water until the pH of the washing liquid reached 7, and dried at 100° C. for 20 hours to obtain a magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine;

[0060] At room temperature, under nitrogen protection, 10g of styrene, 1g of divinylbenzene, 0.3g of 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double metal hydroxide and 0.3g of diisobutyl peroxydicarbonate were stirred evenly, heated to 80°C, reacted for 3h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 70°C for 18h, and ion exchange resin composite white balls were obtained after sieving;

[0061] At room temperature, 10 g of ion exchange resin composite white balls were added to 150 mL of dichloroethane, stirred and swollen for 1.5 h, then 40 mL of chloromethyl ether was added, and the reaction was continued at 45 ° C for 11 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material;

[0062] At room temperature, 10 g of the chloromethylated ion exchange resin composite material was added to 40 mL of a 30% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 9 with a 1 mol / L Na2CO3 aqueous solution. The mixture was stirred at 80 rpm for 11 h at 115°C, cooled to room temperature, and filtered to obtain an anion exchange resin composite material.

[0063] At room temperature, 10 g of anion exchange resin composite material was ultrasonically soaked in 30 mL of acetone for 18 h, and the acetone was filtered out and then loaded into a washing column with a filling capacity of 70%. The anion exchange resin composite material was washed from top to bottom through the washing column with 70°C deionized water, 30°C 30% trimethylamine aqueous solution, and 30°C 1 mol / L Na2CO3 aqueous solution at a speed of 1.5 BV / h for 3 h, and then the anion exchange resin composite material was washed from top to bottom through the washing column with 70°C deionized water until the pH of the washing liquid was 7, and then vacuum dried at 70°C for 18 h to prepare a nuclear-grade ion exchange resin-based composite material.

[0064] The nuclear-grade ion exchange resin-based composite material is obtained by the preparation method of this embodiment.

[0065] The nuclear-grade ion exchange resin-based composite material of this embodiment is used in the purification of water in various loops of a nuclear power plant or a nuclear power plant or in the preparation of ultrapure water.

[0066] A nuclear-grade ion exchange device is prepared using the nuclear-grade ion exchange resin-based composite material of this embodiment.

[0067] Comparative Example 1

[0068] Compared with Example 1, this comparative example is the same as Example 1 except that the raw materials used are all chemically pure.

[0069] Comparative Example 2 (Compared with Example 1, no magnesium aluminum double hydroxide was added)

[0070] A method for preparing an ion exchange resin-based composite material comprises the following steps:

[0071] At room temperature, under nitrogen protection, 10 g of styrene, 0.8 g of divinylbenzene, 0.1 g of 5-vinyl-2,2'-bipyridine and 0.3 g of cyclohexanone peroxide were stirred evenly, heated to 60°C, reacted for 2 h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 60°C for 12 h, and ion exchange resin composite white balls were obtained after sieving;

[0072] At room temperature, 10 g of ion exchange resin composite white balls were added to 100 mL of dichloroethane, stirred and swollen for 1 h, and then 30 mL of chloromethyl ether was added. The reaction was continued at 40° C. for 10 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material.

[0073] At room temperature, 10 g of the chloromethylated ion exchange resin composite material was added to 30 mL of a 30% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 8 with a 1 mol / L Na2CO3 aqueous solution. The mixture was stirred at 50 rpm for 10 h at 110° C., cooled to room temperature, and filtered to obtain an anion exchange resin composite material.

[0074] At room temperature, 10 g of anion exchange resin composite material was ultrasonically soaked in 20 mL of acetone for 12 h, and the acetone was filtered out and then loaded into a washing column with a filling capacity of 60%. The anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water, 20°C 30% trimethylamine aqueous solution, and 20°C 1 mol / L Na2CO3 aqueous solution at a speed of 1 BV / h for 2 h, and then the anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water until the pH of the washing liquid was 7, and then vacuum dried at 60°C for 12 h to prepare an ion exchange resin-based composite material.

[0075] Comparative Example 3 (Compared with Example 1, 5-vinyl-2,2'-bipyridine was not added)

[0076] A method for preparing an ion exchange resin-based composite material comprises the following steps:

[0077] At room temperature, 0.1 g of polyvinyl pyrrolidone, 0.1 g of citric acid, 200 g of deionized water, and 200 g of anhydrous methanol were added to a reactor, and ultrasonic stirring was performed for 0.5 h. Then, 10 g of aluminum nitrate and 8 g of magnesium nitrate were added to the reactor under stirring. After the magnesium nitrate and aluminum nitrate were completely dissolved, ultrasonic stirring was continued for 0.5 h. Then, 2 g of sodium hydroxide was added to the reactor, and hydrothermal reaction was performed at 130° C. for 3 h. After cooling to room temperature, the mixture was filtered, and the filter cake was washed alternately with anhydrous methanol and deionized water until the pH of the washing liquid reached 7, and dried at 80° C. for 10 h to obtain magnesium aluminum double metal hydroxide.

[0078] At room temperature, under nitrogen protection, 10g of styrene, 0.8g of divinylbenzene, 0.1g of magnesium aluminum double hydroxide and 0.3g of cyclohexanone peroxide were stirred evenly, heated to 60°C, reacted for 2h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 60°C for 12h, and ion exchange resin composite white balls were obtained after sieving;

[0079] At room temperature, 10 g of ion exchange resin composite white balls were added to 100 mL of dichloroethane, stirred and swollen for 1 h, and then 30 mL of chloromethyl ether was added. The reaction was continued at 40° C. for 10 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material.

[0080] At room temperature, 10 g of the chloromethylated ion exchange resin composite material was added to 30 mL of a 30% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 8 with a 1 mol / L Na2CO3 aqueous solution. The mixture was stirred at 50 rpm for 10 h at 110° C., cooled to room temperature, and filtered to obtain an anion exchange resin composite material.

[0081] At room temperature, 10 g of anion exchange resin composite material was ultrasonically soaked in 20 mL of acetone for 12 h, and the acetone was filtered out and then loaded into a washing column with a filling capacity of 60%. The anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water, 20°C 30% trimethylamine aqueous solution, and 20°C 1 mol / L Na2CO3 aqueous solution at a speed of 1 BV / h for 2 h, and then the anion exchange resin composite material was washed from top to bottom through the washing column with 50°C deionized water until the pH of the washing liquid was 7, and then vacuum dried at 60°C for 12 h to prepare an ion exchange resin-based composite material.

[0082] Comparative Example 4 (Compared with Example 1, the anion exchange resin composite material was not subjected to acetone and deionized water cleaning and purification, secondary quaternization and transformation treatment)

[0083] A method for preparing an ion exchange resin-based composite material comprises the following steps:

[0084] At room temperature, 0.1 g of polyvinyl pyrrolidone, 0.1 g of citric acid, 3 g of 5-vinyl-2,2'-bipyridine, 200 g of deionized water, and 200 g of anhydrous methanol were added to a reactor, and ultrasonic stirring was performed for 0.5 h. Then, 10 g of aluminum nitrate and 8 g of magnesium nitrate were added to the reactor under stirring. After the magnesium nitrate and aluminum nitrate were completely dissolved, ultrasonic stirring was continued for 0.5 h. Then, 2 g of sodium hydroxide was added to the reactor, and hydrothermal reaction was performed at 130° C. for 3 h. After cooling to room temperature, the mixture was filtered, and the filter cake was washed alternately with anhydrous methanol and deionized water until the pH of the washing solution reached 7, and dried at 80° C. for 10 h to obtain a magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine.

[0085] At room temperature, under nitrogen protection, 10 g of styrene, 0.8 g of divinylbenzene, 0.1 g of 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide and 0.3 g of cyclohexanone peroxide were stirred evenly, heated to 60°C, reacted for 2 h, cooled to room temperature and filtered, the filter cake was washed alternately with anhydrous methanol and deionized water, vacuum dried at 60°C for 12 h, and ion exchange resin composite white balls were obtained after sieving;

[0086] At room temperature, 10 g of ion exchange resin composite white balls were added to 100 mL of dichloroethane, stirred and swollen for 1 h, and then 30 mL of chloromethyl ether was added. The reaction was continued at 40° C. for 10 h, cooled to room temperature, and filtered to obtain a chloromethylated ion exchange resin composite material.

[0087] At room temperature, 10 g of chloromethylated ion exchange resin composite material was added to 30 mL of 30% trimethylamine aqueous solution, and the pH of the mixed solution was adjusted to 8 using 1 mol / L Na2CO3 aqueous solution. The mixture was stirred at 50 rpm for 10 h at 110°C, cooled to room temperature, filtered, washed with deionized water until the pH of the washing liquid was 7, and vacuum dried at 60°C for 12 h to prepare an ion exchange resin-based composite material.

[0088] The performance data of the ion exchange resin-based composite materials obtained in Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Table 1 below.

[0089] Table 1 Technical indicators of ion exchange resin-based composite materials

[0090]

[0091]

[0092] Comparative Example 1 and Comparative Example 1 show that if the raw materials are not purified, the force on the spheres of the nuclear-grade ion exchange resin-based composite material will be uneven, thereby affecting the crushing strength of the nuclear-grade ion exchange resin-based composite material, and the impurity content of the prepared nuclear-grade ion exchange resin-based composite material will increase, resulting in a significant decrease in the transformation rate and volume exchange capacity. Comparative Example 1 and Comparative Example 2 show that magnesium-aluminum double metal hydroxide can effectively improve the crushing strength of the nuclear-grade ion exchange resin-based composite material, making it difficult to break in the nuclear power plant environment, and magnesium-aluminum double metal hydroxide can improve the transformation rate of the nuclear-grade ion exchange resin-based composite material, further affecting the exchange capacity of the nuclear-grade ion exchange resin-based composite material. Comparative Example 1 and Comparative Example 3 show that the introduction of 5-vinyl-2,2'-bipyridine can effectively reduce the dissolution of organic solvents in the nuclear-grade ion exchange resin-based composite material; at the same time, it is conducive to the uniform dispersion of magnesium aluminum double metal hydroxide in the resin, and the intercalation of 5-vinyl-2,2'-bipyridine to magnesium aluminum double metal hydroxide avoids the intercalation of carbonate ions to magnesium aluminum double metal hydroxide during the transformation process, which greatly reduces the residual carbonate ions in the nuclear-grade ion exchange resin-based composite material. 5-vinyl-2,2'-bipyridine and magnesium aluminum double metal hydroxide work together to further improve the exchange capacity and transformation rate of the nuclear-grade ion exchange resin-based composite material. Comparative Example 1 and Comparative Example 4 show that without acetone and deionized water cleaning and purification, secondary quaternization and transformation treatment, the residual soluble organic matter and impurities in the nuclear-grade ion exchange resin-based composite material are high, which will affect the purity and exchange capacity of the nuclear-grade ion exchange resin-based composite material.

[0093] It should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in less than all of the features of the previously disclosed embodiments. Therefore, the claims that follow the detailed description are hereby expressly incorporated into the detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0094] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

[0095] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a nuclear-grade ion exchange resin-based composite material, characterized in that: The following steps are involved: Step 1, purifying polyvinyl pyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, aluminum salt, magnesium salt, precipitant, styrene, divinylbenzene, initiator, ethylene dichloride, chloromethyl ether, trimethylamine, Na2CO3, acetone, deionized water, and anhydrous methanol; Step 2: Add polyvinyl pyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, deionized water and anhydrous methanol to a reaction kettle at room temperature, and stir ultrasonically for 0.5 to 2 hours. Continue to add aluminum salt and magnesium salt to the reaction kettle under stirring. After the magnesium salt and aluminum salt are completely dissolved, continue to stir ultrasonically for 0.5 to 2 hours, and continue to add a precipitant to the reaction kettle. The mass ratio of deionized water: anhydrous methanol: polyvinyl pyrrolidone: citric acid: 5-vinyl-2,2'-bipyridine: precipitant: magnesium salt: aluminum salt is (20-50): (20-50): (0.01-0.05): (0.01-0.1): (0.3-1): (0.2-2): (0.8-2): 1; hydrothermal reaction is carried out at 130-180° C. for 3-6 hours, and the mixture is filtered after cooling to room temperature. The filter cake is washed alternately with anhydrous methanol and deionized water until the pH value of the washing liquid reaches 7, and dried at 80-120° C. for 10-24 hours to obtain magnesium aluminum double hydroxide intercalated with 5-vinyl-2,2'-bipyridine; Step 3, at room temperature, under nitrogen protection, styrene, divinylbenzene, 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide and initiator are stirred evenly; the mass ratio of divinylbenzene: 5-vinyl-2,2'-bipyridine intercalated magnesium aluminum double hydroxide: initiator: styrene is (0.08-0.18): (0.01-0.05): (0.03-0.05): 1; heating to 60-90°C, reacting for 2-5h, cooling to room temperature and filtering, washing the filter cake alternately with anhydrous methanol and deionized water, vacuum drying at 60-80°C for 12-24h, and obtaining ion exchange resin composite white balls after sieving; Step 4: Add the ion exchange resin composite material white ball to dichloroethane at room temperature, stir and swell for 1 to 2 hours, and then add chloromethyl ether; the volume mass ratio of dichloroethane: ion exchange resin composite material white ball is (10 to 20): 1, in mL / g; the volume mass ratio of chloromethyl ether: ion exchange resin composite material white ball is (3 to 5): 1, in mL / g; continue to react for 10 to 12 hours at 40 to 50° C., cool to room temperature, and filter to obtain the chloromethylated ion exchange resin composite material; Step 5, at room temperature, adding the chloromethylated ion exchange resin composite material to a 30-40% trimethylamine aqueous solution, the volume mass ratio of the 30-40% trimethylamine aqueous solution: the chloromethylated ion exchange resin composite material is (3-5): 1, the unit is mL / g; using a Na2CO3 aqueous solution to adjust the pH of the mixed solution to 8-10, stirring the reaction at 110-120°C for 10-12h, cooling to room temperature, and filtering to obtain an anion exchange resin composite material; Step six, at room temperature, ultrasonically soak the anion exchange resin composite material in acetone for 12 to 24 hours, the volume mass ratio of acetone: anion exchange resin composite material is (2 to 4): 1, the unit is mL / g; after filtering out the acetone, load it into a washing column, wash it with deionized water, 30 to 40% trimethylamine aqueous solution, 1 to 1.5 mol / L Na2CO3 aqueous solution, and deionized water in sequence, and vacuum dry it at 60 to 80°C for 12 to 24 hours to prepare a nuclear-grade ion exchange resin-based composite material.

2. The preparation method according to claim 1, characterized in that: In step 1, the impurity content of polyvinylpyrrolidone, citric acid, 5-vinyl-2,2'-bipyridine, aluminum salt, magnesium salt, precipitant, styrene, divinylbenzene, initiator, dichloroethane, chloromethyl ether, trimethylamine, Na2CO3, acetone and anhydrous methanol after purification is less than 1ppm, and the deionized water reaches 18 mega high-purity water after purification.

3. The preparation method according to claim 1, characterized in that: In step 1, the aluminum salt is selected from aluminum nitrate or aluminum isopropoxide, the magnesium salt is selected from magnesium nitrate or magnesium acetate, the precipitant is selected from ammonia water or sodium hydroxide, and the initiator is selected from cyclohexanone peroxide or diisobutyl peroxydicarbonate.

4. The preparation method according to claim 1, characterized in that: In step 2, the mass ratio of deionized water to anhydrous methanol is 1:

1.

5. The preparation method according to claim 1, characterized in that: In step 5, the concentration of the Na2CO3 aqueous solution is 1-1.5 mol / L.

6. The preparation method according to claim 1, characterized in that: The stirring rate is 50-100 rpm; the ultrasonic power is 100-500W.

7. The preparation method according to claim 1, characterized in that: In step six, the filling amount of the washing column is 60-80%; the deionized water washing temperature is 50-80°C, the washing temperature of the 30-40% trimethylamine aqueous solution and the 1-1.5 mol / L Na2CO3 aqueous solution is 20-40°C, and the washing method is to pass through the washing column from top to bottom at a speed of 1-2BV / h. The first deionized water washing, the 30-40% trimethylamine aqueous solution washing and the 1-1.5 mol / L Na2CO3 aqueous solution washing time are all 2-4h, and the end point of the second deionized water washing is when the pH of the washing liquid reaches 7.

8. The nuclear-grade ion exchange resin-based composite material obtained by the preparation method according to any one of claims 1 to 7, characterized in that: Average crushing strength ≥350g / particle, transformation rate greater than ≥94%, volume exchange capacity ≥1.3eq / L, Cl - Content ≤0.2%, SO4 2- Content ≤0.2%, CO3 2- Content ≤4.3%, organic extractables ≤0.09%.

9. Use of the nuclear-grade ion exchange resin-based composite material according to claim 8 in the purification of water in various circuits of a nuclear power plant or a nuclear power plant or in the preparation of ultrapure water.

10. A nuclear grade ion exchange device, characterized in that: The composite material is prepared by using the nuclear-grade ion exchange resin-based composite material described in claim 8.

Images