Resins, methods for their preparation and use

Abstract

This invention discloses a resin, its preparation method, and its uses. The resin possesses rigid bidentate ligands and exhibits excellent adsorption performance for uranium in seawater.

Description

Technical Field

[0001] This invention relates to a resin, its preparation method, and its uses. Background Technology

[0002] Currently, terrestrial uranium resources are relatively scarce, and the grade of uranium ore is low, resulting in high mining costs. The ocean, on the other hand, contains abundant uranium resources. Compared to terrestrial mining, seawater uranium extraction has a smaller impact on the ecological environment. Seawater uranium extraction materials are the material basis for seawater uranium extraction, which involves reacting with UO2 in seawater. 2+ Coordination and complexation are used to achieve the adsorption of uranium.

[0003] As fundamental materials in the seawater uranium extraction process, various types of adsorbent materials have been developed through years of research. Classified by material form, materials can be categorized into fibrous materials, membrane materials, non-woven fabric materials, microsphere materials, and amorphous solid materials; classified by chemical composition, materials can be categorized into organic polymer materials, inorganic materials, organic-inorganic hybrid materials, and bio-based materials. Microsphere materials have attracted increasing attention due to their advantages of good uniformity, strong mechanical properties, and high industrialization potential. However, commonly used microsphere materials (such as styrene-divinylbenzene copolymers) are unsuitable for seawater uranium extraction and therefore require modification. Summary of the Invention

[0004] In view of this, one object of the present invention is to provide a resin having rigid bidentate ligands. Furthermore, this resin exhibits good adsorption properties for uranium extraction from seawater.

[0005] Another object of the present invention is to provide a method for preparing a resin.

[0006] Another object of the present invention is to provide a use of a resin compound.

[0007] On one hand, the resin of the present invention is a polymer formed by replacing at least a portion of the hydrogen atoms on the benzene ring of a styrene-divinylbenzene copolymer with substituent groups represented by one of the following formulas:

[0008]

[0009] Where n is selected from integers greater than or equal to 0.

[0010] Using styrene-divinylbenzene copolymer as a raw material, at least a portion of the hydrogen atoms on the benzene ring are replaced by the aforementioned substituent groups to form the resin of the present invention. In some embodiments, a portion of the hydrogen atoms on the benzene ring of the styrene-divinylbenzene copolymer are replaced by the aforementioned substituent groups. Therefore, at least a portion of the benzene ring of the resin of the present invention carries the aforementioned substituent groups. In some embodiments, all benzene rings of the resin of the present invention carry the aforementioned substituent groups.

[0011] According to the resin of the present invention, preferably, n is selected from an integer from 0 to 8. According to the resin of the present invention, preferably, n is selected from an integer from 0 to 4. According to one embodiment of the present invention, n is selected from an integer from 2 to 3.

[0012] The resin of this invention contains rigid bidentate ligands. Such ligands have relatively fixed bonding angles between their bonding sites, relatively fixed coordination modes, and conjugated structures, resulting in more stable complex structures. The resin of this invention exhibits excellent adsorption performance in uranium extraction from seawater.

[0013] The resin according to the present invention is preferably a polymer microsphere. Microsphere materials have advantages such as good uniformity and strong mechanical properties, and the resin in microsphere form exhibits better adsorption performance in seawater uranium extraction.

[0014] On the other hand, the present invention provides a method for preparing the above-mentioned resin, comprising the following steps:

[0015] (1) The chloromethylated styrene-divinylbenzene copolymer was reacted with an amination reagent to obtain an amination;

[0016] (2) The amine was reacted with pyridine-2-carboxaldehyde to obtain the resin;

[0017] The amination reagent is selected from ammonia or a compound having the following structure:

[0018]

[0019] Where n is selected from integers greater than or equal to 0.

[0020] In this invention, preferably, n is selected from an integer from 0 to 8; more preferably, n is selected from an integer from 0 to 4. According to one embodiment of the invention, n is selected from an integer from 2 to 3.

[0021] Examples of amination reagents of the present invention include, but are not limited to, ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. The ammonia solution can be concentrated ammonia. The concentration of the ammonia solution can be 20–28 vol%. In some embodiments, the concentration of the ammonia solution is 22–25 vol%. According to one embodiment of the present invention, the amination reagent is triethylenetetramine.

[0022] Chloromethylated styrene-divinylbenzene copolymers can be polymer microspheres. These microsphere-like chloromethylated styrene-divinylbenzene copolymers can also be referred to as chlorospheres.

[0023] According to the preparation method of the present invention, preferably, the molar ratio of chloromethylated styrene-divinylbenzene copolymer to amination reagent is 1:(3-40); the molar ratio of amination to pyridine-2-carboxaldehyde is 1:(2-5).

[0024] In this invention, the molar ratio of chloromethylated styrene-divinylbenzene copolymer to amination reagent is preferably 1:(3-15); more preferably 1:(4-8).

[0025] In this invention, the molar ratio of the amine to pyridine-2-carboxaldehyde is preferably 1:(3-5); more preferably 1:(3-4).

[0026] According to the preparation method of the present invention, preferably, in step (1), the reaction of the chloromethylated styrene-divinylbenzene copolymer with the amination reagent is carried out in the presence of a mixture of water and aliphatic monohydric alcohol; wherein the volume ratio of water to aliphatic monohydric alcohol is 1:(2-6); in step (2), the reaction of the amination with pyridine-2-carboxaldehyde is carried out in the presence of aliphatic monohydric alcohol.

[0027] According to the preparation method of the present invention, preferably, the aliphatic monohydric alcohol in steps (1) and (2) is selected from one or more of methanol and ethanol.

[0028] In step (1), the volume ratio of water to aliphatic monohydric alcohol is preferably 1:(3-5). According to one embodiment of the present invention, the aliphatic monohydric alcohol is methanol. The mass-to-volume ratio of the chloromethylated styrene-divinylbenzene copolymer to the mixture can be 1:(2-8) g / mL; preferably 1:(3-5) g / mL. The reaction temperature of the chloromethylated styrene-divinylbenzene copolymer with the amination reagent can be 60-120°C; preferably 70-90°C. The reaction time can be 10-36 h; preferably 20-30 h. The reaction can be carried out in a reflux reflux apparatus.

[0029] In some embodiments, the process further includes filtering, washing, and drying the intermediate product obtained by reacting the chloromethylated styrene-divinylbenzene copolymer with an amination reagent. The solid intermediate product obtained after filtration can be washed with one or more solvents selected from water, methanol, or ethanol. According to one embodiment of the invention, the product is first washed with water, then washed with ethanol. The number of washes is not limited, but multiple washes are preferred, for example, 3 to 6 times.

[0030] In step (2), the mass-to-volume ratio of the chloromethylated styrene-divinylbenzene copolymer to the aliphatic monohydric alcohol can be 1:(2-8) g / mL; preferably 1:(3-5) g / mL. According to one embodiment of the present invention, the aliphatic monohydric alcohol is preferably ethanol.

[0031] According to the preparation method of the present invention, preferably, the reaction between the amine and pyridine-2-carboxaldehyde is carried out under a nitrogen atmosphere, and glacial acetic acid or sulfuric acid is also present in the reaction system.

[0032] The mass-to-volume ratio of chloromethylated styrene-divinylbenzene copolymer to glacial acetic acid (or sulfuric acid) can be (3-9):1 g / mL; preferably (5-7):1 g / mL.

[0033] The reaction temperature between the amine and pyridine-2-carboxaldehyde can be 70–120°C; preferably 75–90°C. The reaction time can be 10–36 h; preferably 20–30 h. The reaction can be carried out in a heated reflux apparatus.

[0034] In some embodiments, the process further includes filtering, washing, and drying the reaction product obtained by reacting the amine with pyridine-2-carboxaldehyde. The solid product obtained after filtration can be washed with one or more solvents selected from water, methanol, or ethanol. According to one embodiment of the invention, the product is first washed with water, then with ethanol. The number of washes is not limited, but multiple washes are preferred, for example, 3 to 6 times.

[0035] Furthermore, the present invention provides the use of the above-mentioned resin in the separation of uranium. Specifically, the resin of the present invention is capable of separating uranium from seawater.

[0036] The resin of this invention contains rigid bidentate ligands, which exhibits good adsorption performance in uranium extraction from seawater. Attached Figure Description

[0037] Figure 1 The infrared spectra of the chlorine balls and the product obtained in Example 4 are shown.

[0038] Figure 2 The thermogravimetric analysis (TGA) of the resin obtained in Example 4 is shown. Detailed Implementation

[0039] The testing method is described below:

[0040] Saturated adsorption capacity: 100 mg of resin and 2000 mL of uranium-containing seawater (uranium concentration of 3.7 mg / L) were placed in an Erlenmeyer flask, and then shaken at 150 r / min for 24 h at room temperature. After shaking, the resin was filtered, and the concentration of uranium in the uranium-containing seawater after adsorption was measured to obtain the saturated adsorption capacity.

[0041] The main raw materials are described below:

[0042] Chlorine spheres: Chloromethylated styrene-divinylbenzene copolymer (purchased from Zhejiang Zhengguang Industrial Co., Ltd., chlorine content 17%, molecular weight 30,000-50,000).

[0043] Examples 1-5

[0044] 20 g of chlorinated globules and an amination reagent were heated under reflux at 80 °C for 24 h in 80 mL of a mixture of water and methanol. After cooling, an intermediate product was obtained. The molar ratio of chlorinated globules to the amination reagent was 1:5, and the volume ratio of water to methanol was 1:4. The intermediate product was filtered to obtain a solid intermediate product. The solid intermediate product was washed three times with 20 mL of deionized water each time; then washed three times with 20 mL of ethanol each time. After drying, the amination product was obtained.

[0045] Under a nitrogen atmosphere, the amine and pyridine-2-carboxaldehyde were heated to reflux at 80°C for 24 h in 80 mL of ethanol in the presence of 3 mL of glacial acetic acid. After cooling, the reaction product was obtained. The molar ratio of the amine to pyridine-2-carboxaldehyde was 1:3. The reaction product was filtered to obtain a solid product. The solid product was washed three times with 20 mL of deionized water each time; then washed three times with 20 mL of ethanol each time. After drying, the resin was obtained.

[0046] See Table 1 for details.

[0047] Comparative Example 1

[0048] The saturated adsorption capacity of the chlorine beads was determined using the above method, and the results are shown in Table 1.

[0049] Table 1

[0050] Serial Number Amination reagents Saturated adsorption capacity (mg / g) Example 1 Ammonia solution with a concentration of 25 vol% 14.47 Example 2 ethylenediamine 45.59 Example 3 Diethylenetriamine 43.81 Example 4 Triethylenetetramine 70.64 Example 5 Tetraethylenepentamine 24.35 Comparative Example 1 Resin Chloride Balls 0.78

[0051] Note: The number of moles of ammonia water is calculated based on the amount of NH3·H2O it contains.

[0052] This invention is not limited to the above-described embodiments. Any modifications, improvements, or substitutions that can be conceived by those skilled in the art without departing from the essential content of this invention fall within the scope of this invention.

Claims

1. A method for preparing a resin, characterized in that, Includes the following steps: (1) Chloromethylated styrene-divinylbenzene copolymer and triethylenetetramine are reacted at 70-90°C for 20-30 h in the presence of a mixture of water and methanol to obtain an amination; wherein the molar ratio of chloromethylated styrene-divinylbenzene copolymer to triethylenetetramine is 1: (4-8), and the volume ratio of water to methanol is 1: (2-6); (2) The amine is reacted with pyridine-2-carboxaldehyde to obtain a resin; the molar ratio of the amine to pyridine-2-carboxaldehyde is 1:(3-5).

2. The preparation method according to claim 1, characterized in that: In step (2), the reaction of the amine with pyridine-2-carboxaldehyde is carried out in the presence of an aliphatic monohydric alcohol.

3. The preparation method according to claim 2, characterized in that, The aliphatic monohydric alcohol in step (2) is selected from one or more of methanol and ethanol.

4. The preparation method according to claim 2, characterized in that, In step (2), the reaction between the amine and pyridine-2-carboxaldehyde is carried out under a nitrogen atmosphere, and glacial acetic acid or sulfuric acid is also present in the reaction system.

5. Use of the resin obtained by the preparation method according to any one of claims 1 to 4 in uranium separation.

Images