阅读说明：本技术 一种甲基吡啶树脂及其制备方法和应用 (Methylpyridine resin and preparation method and application thereof ) 是由 勾阳飞 陈树森 宿延涛 王凤菊 宋艳 常华 王海珍 李默 李子明 于 2021-09-10 设计创作，主要内容包括：本发明提供了一种甲基吡啶树脂及其制备方法和应用,属于废水处理技术领域。本发明以丙烯酸类单体进行悬浮聚合制备丙烯酸骨架共聚物交联微球,然后以甲基吡啶为功能化单体对丙烯酸骨架共聚物交联微球进行化学改性,将甲基吡啶功能基团接枝到丙烯酸骨架微球中,所制备的甲基吡啶树脂中甲基吡啶功能基团对铀酰离子具有良好的选择性,其结构为五元氮杂环结构,有利于铀酰离子与氮原子络合,所以在吸附铀过程中受空间位阻干扰较小,空间位阻效应对其铀吸附性能影响较低；从而使得所制备的甲基吡啶树脂具有较高的铀选择性和吸附容量。(The invention provides a picoline resin and a preparation method and application thereof, belonging to the technical field of wastewater treatment. According to the invention, acrylic acid skeleton copolymer crosslinked microspheres are prepared by suspension polymerization of acrylic monomers, then, the acrylic acid skeleton copolymer crosslinked microspheres are chemically modified by taking picoline as a functional monomer, and a picoline functional group is grafted to the acrylic acid skeleton microspheres, so that the picoline functional group in the prepared picoline resin has good selectivity on uranyl ions, and the structure of the picoline resin is a five-membered nitrogen heterocyclic structure, which is beneficial to complexation of the uranyl ions and nitrogen atoms, therefore, the interference of steric hindrance in the uranium adsorption process is small, and the influence of the steric hindrance effect on the uranium adsorption performance is low; therefore, the prepared picoline resin has higher uranium selectivity and adsorption capacity.)

1. The preparation method of the picoline resin is characterized by comprising the following steps of:

mixing an acrylic monomer, a cross-linking agent, an initiator and a pore-forming agent, mixing the obtained organic phase with a dispersant aqueous solution, and carrying out suspension polymerization reaction to obtain organic beads;

curing the organic beads to obtain acrylic acid skeleton copolymer crosslinked microspheres;

and mixing the acrylic acid skeleton copolymer crosslinked microspheres, an alcohol-water solution and picoline for modification to obtain the picoline resin.

2. The production method according to claim 1, wherein the acrylic monomer comprises acrylic acid, methyl acrylate or methyl methacrylate; the crosslinking agent comprises divinylbenzene; the initiator comprises benzoyl peroxide or azobisisobutyronitrile.

3. The preparation method according to claim 1, wherein the pore-forming agent comprises one or two of isooctane, toluene and liquid paraffin; the dispersant in the dispersant aqueous solution comprises gelatin or kaolin, and the mass ratio of the dispersant to water in the dispersant aqueous solution is (0.005-0.01): 1; the volume ratio of the dispersant aqueous solution to the organic phase is (1.6-4.0): 1.

4. The production method according to claim 1, 2 or 3, wherein the mass of the crosslinking agent is 6 to 18% of the total mass of the acrylic monomer and the crosslinking agent; the mass of the initiator is 0.5-1.5% of the total mass of the acrylic monomer and the cross-linking agent; the ratio of the mass of the pore-foaming agent to the total mass of the acrylic monomer and the cross-linking agent is (0.8-1): 1.

5. The preparation method according to claim 1, wherein the suspension polymerization reaction is carried out at a temperature of 70-78 ℃ for 2-4 hours.

6. The method according to claim 1, wherein the curing temperature is 80-95 ℃ and the curing time is 8-12 h.

7. The preparation method of claim 1, wherein the mass ratio of the methylpyridine to the acrylic acid skeleton copolymer crosslinked microspheres is (0.5-3.5): 1; the ratio of the mass of the acrylic acid skeleton copolymer crosslinked microspheres to the volume of the alcohol-water solution is 1 g: (1-4) mL.

8. The preparation method according to claim 1 or 7, wherein the modification temperature is 65-85 ℃ and the modification time is 2-48 h.

9. A picoline resin produced by the process of any one of claims 1 to 8.

10. Use of the picoline resin of claim 9 in the treatment of neutral uranium-bearing wastewater.

Technical Field

The invention relates to the technical field of wastewater treatment, and particularly relates to a picoline resin and a preparation method and application thereof.

Background

With the rapid development of the nuclear industry, the demand of natural uranium is more and more large, and a large amount of uranium-containing wastewater is generated in the process of mining uranium ores and uranium hydrometallurgy. The uranium-bearing wastewater can not only pollute surface water, but also infiltrate underground polluted underground water to cause serious damage to the environment. Therefore, the natural uranium is developed by considering not only the utilization problem of uranium resources but also the safety and environmental protection problem in the mining process.

At present, the traditional methods for treating uranium-containing wastewater include an ion exchange method, a chemical precipitation method, an evaporation concentration method, a membrane separation method, a biochemical method and the like. Wherein, the ion exchange method is a relatively efficient, economic and reliable method for treating uranium-containing wastewater. The principle of the ion exchange method is that when ion exchange resin is contacted with uranium-containing wastewater, exchangeable functional groups on the resin interact with uranyl ions in the wastewater to adsorb the uranyl ions onto the resin, so that the purpose of removing the uranyl ions from the wastewater is achieved. The ion exchange resin is a high polymer electrolyte with a three-dimensional network structure of functional groups, has the advantages of large processing capacity, high adsorption capacity, capability of removing various ions, repeated regeneration and use and long service life. However, the existing conventional ion exchange resin has low adsorption capacity to uranium in the neutral uranium-containing wastewater and poor adsorption effect.

Disclosure of Invention

The invention aims to provide a picoline resin, a preparation method and application thereof, and the prepared picoline resin has high adsorption capacity on uranium in neutral uranium-containing wastewater.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a preparation method of picoline resin, which comprises the following steps:

mixing an acrylic monomer, a cross-linking agent, an initiator and a pore-forming agent, mixing the obtained organic phase with a dispersant aqueous solution, and carrying out suspension polymerization reaction to obtain organic beads;

curing the organic beads to obtain acrylic acid skeleton copolymer crosslinked microspheres;

and mixing the acrylic acid skeleton copolymer crosslinked microspheres, an alcohol-water solution and picoline for modification to obtain the picoline resin.

Preferably, the acrylic monomer comprises acrylic acid, methyl acrylate or methyl methacrylate; the crosslinking agent comprises divinylbenzene; the initiator comprises benzoyl peroxide or azobisisobutyronitrile.

Preferably, the pore-foaming agent comprises one or two of isooctane, toluene and liquid paraffin; the dispersant in the dispersant aqueous solution comprises gelatin or kaolin, and the mass ratio of the dispersant to water in the dispersant aqueous solution is (0.005-0.01): 1; the volume ratio of the dispersant aqueous solution to the organic phase is (1.6-4.0): 1.

Preferably, the mass of the cross-linking agent is 6-18% of the total mass of the acrylic monomer and the cross-linking agent; the mass of the initiator is 0.5-1.5% of the total mass of the acrylic monomer and the cross-linking agent; the ratio of the mass of the pore-foaming agent to the total mass of the acrylic monomer and the cross-linking agent is (0.8-1): 1.

Preferably, the temperature of the suspension polymerization reaction is 70-78 ℃ and the time is 2-4 h.

Preferably, the curing temperature is 80-95 ℃ and the curing time is 8-12 h.

Preferably, the mass ratio of the picoline to the acrylic acid skeleton copolymer crosslinked microspheres is (0.5-3.5): 1; the ratio of the mass of the acrylic acid skeleton copolymer crosslinked microspheres to the volume of the alcohol-water solution is 1 g: (1-4) mL.

Preferably, the modification temperature is 65-85 ℃ and the modification time is 2-48 h.

The invention provides the methylpyridine resin prepared by the preparation method in the technical scheme.

The invention provides application of the picoline resin in the technical scheme in treatment of neutral uranium-containing wastewater.

The invention provides a preparation method of picoline resin, which comprises the following steps: mixing an acrylic monomer, a cross-linking agent, an initiator and a pore-forming agent, mixing the obtained organic phase with a dispersant aqueous solution, and carrying out suspension polymerization reaction to obtain organic beads; curing the organic beads to obtain acrylic acid skeleton copolymer crosslinked microspheres; and mixing the acrylic acid skeleton copolymer crosslinked microspheres, an alcohol-water solution and picoline for modification to obtain the picoline resin. According to the invention, acrylic acid skeleton copolymer crosslinked microspheres are prepared by suspension polymerization of acrylic monomers, then, the acrylic acid skeleton copolymer crosslinked microspheres are chemically modified by taking methyl pyridine as a functional monomer, and a methyl pyridine functional group is grafted to the acrylic acid skeleton microspheres, so that the methyl pyridine functional group in the prepared methyl pyridine resin has good selectivity on uranyl ions, the structure of the methyl pyridine resin is a five-membered nitrogen heterocyclic structure, N atoms contain lone pair electrons, and the capture of the uranyl ions by nitrogen atoms through a chelating effect is facilitated, therefore, the interference of steric hindrance in the uranium adsorption process is small, and the influence of the steric hindrance effect on the uranium adsorption performance is low; therefore, the prepared picoline resin has higher uranium selectivity and adsorption capacity.

The picoline resin prepared by the invention belongs to strongly basic picoline resin (anion exchange resin), has the characteristics of conventional ion exchange resin, is slightly interfered by anions such as chloride ions when being coordinated with uranyl ions in uranium-containing wastewater, and cannot be coordinated with metal cations with larger volume due to the influence of steric hindrance; moreover, the picoline resin has better mechanical strength and reusability.

The methylpyridine resin prepared by the invention is statically adsorbed in uranium-containing wastewater with the uranium concentration of 300mg/L and the chloride root of 23g/L, pH of 6.9, and the adsorption equilibrium capacity of the resin is more than or equal to 70mg/g (dry resin), which indicates that the methylpyridine resin has better adsorption capacity for uranyl ions in neutral uranium-containing wastewater, so that the methylpyridine resin can be adapted to neutral solution environment and can adsorb uranium, can be used for extracting uranium from neutral uranium-containing wastewater, and can effectively reduce the procedure of extracting uranium from a complex solution system, thereby reducing the cost and energy consumption of extracting uranium, providing a novel material for treating mine uranium-containing wastewater, and providing a new idea and method for other unconventional uranium resource uranium extraction technologies.

The invention successfully prepares the picoline resin for adsorbing uranium from neutral uranium-containing wastewater by adopting suspension polymerization and chemical modification technologies, and the preparation method is simple and convenient.

Detailed Description

The invention provides a preparation method of picoline resin, which comprises the following steps:

mixing an acrylic monomer, a cross-linking agent, an initiator and a pore-forming agent, mixing the obtained organic phase with a dispersant aqueous solution, and carrying out suspension polymerization reaction to obtain organic beads;

curing the organic beads to obtain acrylic acid skeleton copolymer crosslinked microspheres;

and mixing the acrylic acid skeleton copolymer crosslinked microspheres, an alcohol-water solution and picoline for modification to obtain the picoline resin.

In the present invention, unless otherwise specified, all the starting materials required for the preparation are commercially available products well known to those skilled in the art.

The preparation method comprises the steps of mixing an acrylic monomer, a cross-linking agent, an initiator and a pore-foaming agent, mixing the obtained organic phase with a dispersant aqueous solution, and carrying out suspension polymerization reaction to obtain the organic ball. In the present invention, the acrylic monomer preferably includes acrylic acid, methyl acrylate or methyl methacrylate; the crosslinking agent preferably comprises divinylbenzene, the divinylbenzene is preferably commercially available divinylbenzene, and the mass content of the commercially available divinylbenzene is preferably 63%. In the invention, the mass of the cross-linking agent is preferably 6-18% of the total mass of the acrylic monomer and the cross-linking agent, and more preferably 13-16%;

in the present invention, the initiator preferably includes benzoyl peroxide or azobisisobutyronitrile; the mass of the initiator is preferably 0.5-1.5%, more preferably 1% of the total mass of the acrylic monomer and the crosslinking agent.

In the present invention, the porogen preferably comprises one or two of isooctane, toluene and liquid paraffin; when the pore-foaming agents are two of the pore-foaming agents, the mixture ratio of different pore-foaming agents is not specially limited, and the pore-foaming agents can be mixed at any ratio; the ratio of the mass of the pore-foaming agent to the total mass of the acrylic monomer and the cross-linking agent is preferably (0.8-1): 1, and more preferably (0.93-0.94): 1.

In the invention, the dispersant in the dispersant aqueous solution preferably comprises gelatin or kaolin, and the mass ratio of the dispersant to water in the dispersant aqueous solution is preferably (0.005-0.01): 1. In the invention, the dispersant aqueous solution is preferably prepared under the heating condition, and the heating temperature is preferably 45-55 ℃.

In the invention, the volume ratio of the dispersant aqueous solution to the organic phase is preferably (1.6-4.0): 1, and more preferably (2.1-3.25): 1.

The process of mixing the acrylic monomer, the cross-linking agent, the initiator and the pore-foaming agent is not particularly limited, and the materials are uniformly mixed according to the process well known in the art.

In the present invention, the process of mixing the obtained organic phase with the aqueous dispersant solution is preferably carried out under stirring conditions until the obtained mixture forms uniformly sized beads. The stirring rate is not particularly limited in the present invention, and the stirring may be performed according to a process well known in the art.

After the mixing of the organic phase and the dispersant aqueous solution is completed, the temperature is preferably raised, the heating rate of raising the temperature to the temperature of the suspension polymerization reaction is preferably 5 ℃/10min, the temperature of the suspension polymerization reaction is preferably 70-78 ℃, more preferably 75 ℃, and the time is preferably 2-4 h.

In the suspension polymerization reaction process, monomer acrylic acid and a cross-linking agent divinylbenzene are polymerized to obtain the acrylic acid-divinylbenzene cross-linked copolymer.

After the suspension polymerization is completed, the present invention preferably cures the resulting organic beads without any treatment.

After the organic ball is obtained, the organic ball is solidified to obtain the acrylic acid skeleton copolymer crosslinked microsphere. In the present invention, the rate of temperature rise to the curing temperature is preferably 5 ℃/10 min; the curing temperature is preferably 80-95 ℃, more preferably 85 ℃, and the curing time is 8-12 hours. In the curing process, the organic beads are gradually formed, the mechanical strength of the microspheres is continuously enhanced along with the increase of the curing time, and the chemical structure is not changed.

After the curing is completed, the resin obtained is preferably sequentially filtered, washed, dried, extracted and sieved to obtain the acrylic acid skeleton copolymer crosslinked microspheres. The invention removes the pore-foaming agent in the obtained resin by extraction. The process of filtering, washing, extracting and sieving is not particularly limited in the present invention and may be performed according to a process well known in the art. In the invention, the drying temperature is preferably 60-80 ℃, and the time is preferably more than or equal to 8 hours.

In the invention, the granularity of the material obtained by sieving is preferably 0.28-0.45 mm, namely the granularity of the acrylic acid skeleton copolymer crosslinked microspheres is preferably 0.28-0.45 mm.

After the acrylic acid skeleton copolymer crosslinked microspheres are obtained, the acrylic acid skeleton copolymer crosslinked microspheres, an alcohol-water solution and picoline are mixed and modified to obtain the picoline resin. In the invention, the mass ratio of the methylpyridine to the acrylic acid skeleton copolymer crosslinked microspheres is preferably (0.5-3.5): 1, more preferably (1-3): 1, and even more preferably (1.5-2): 1.

In the present invention, the alcohol in the alcohol-water solution is preferably ethanol, the volume ratio of ethanol to water is preferably 1:1, and the ratio of the mass of the acrylic acid skeleton copolymer crosslinked microspheres to the volume of the alcohol-water solution is preferably 1 g: (1-4) mL.

In the present invention, the process of mixing the acrylic acid skeleton copolymer crosslinked microspheres, the aqueous alcohol solution and the picoline is preferably to swell the acrylic acid skeleton copolymer crosslinked microspheres in the aqueous alcohol solution, and drop the picoline after sufficient swelling. The present invention does not specifically limit the degree of sufficient swelling, and the degree of sufficient swelling can be determined according to criteria well known in the art; the invention has no special limit on the speed of dripping the picoline and can be dripped dropwise.

In the invention, the modification is preferably carried out under stirring conditions, the temperature of the modification is 65-85 ℃, the more preferable temperature is 75-80, and the time is preferably 2-48 h, and the more preferable time is 24 h. The stirring rate is not particularly limited in the present invention and may be carried out according to a procedure well known in the art.

In the modification process, carboxyl on the acrylic acid skeleton copolymer cross-linked microspheres is chemically combined with pyridine groups in the picoline to form the picoline resin.

After the modification is finished, the product is preferably washed by sequentially adopting methanol and deionized water, and the methyl pyridine resin is obtained after drying. The washing and drying processes are not particularly limited in the present invention and may be performed according to processes well known in the art.

The invention provides the methylpyridine resin prepared by the preparation method in the technical scheme.

The invention provides application of the picoline resin in the technical scheme in treatment of neutral uranium-containing wastewater. The method of the present invention is not particularly limited, and the method may be applied according to a method known in the art. In the application example of the invention, 1g of the picoline resin is placed in 1L of uranium-containing wastewater (mine uranium-containing wastewater) with a uranium concentration of 300mg/L and a chloride concentration of 23g/L, pH value of 6.9 for single static adsorption for 24h, and after the adsorption is finished, the resin is taken out.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Adding 1.6g of kaolin into 160mL of deionized water, and heating to 55 ℃ until the kaolin is completely dispersed to obtain a kaolin aqueous solution; uniformly mixing 40g of methyl acrylate, 6g of divinylbenzene (mass content of 63%), 0.23g of benzoyl peroxide and 43g of liquid paraffin, adding the obtained organic phase (76mL) into the kaolin aqueous solution, stirring to form uniform-sized balls, starting heating, heating to 5 ℃ every 10 minutes, heating to 75 ℃ and reacting for 4 hours; continuously heating to 80 ℃, and curing for 12 h; after the reaction is finished, sequentially filtering, washing and drying the obtained materials (80 ℃, the time is 8 hours), extracting the obtained solid, and then sieving to obtain acrylic acid skeleton copolymer crosslinked microspheres with the granularity of 0.28-0.45 mm;

taking 10g of acrylic acid skeleton copolymer crosslinked microspheres, adding a mixed solution of 10mL of ethanol and 10mL of deionized water, fully swelling, dropwise adding 10g of picoline, starting stirring, reacting at 65 ℃ for 24h, sequentially washing the obtained product with methanol and deionized water, and drying to obtain the picoline resin.

Example 2

Adding 1.4g of gelatin into 280mL of deionized water, and heating to 55 ℃ until the gelatin is completely dispersed to obtain an aqueous solution; uniformly mixing 45g of methyl methacrylate, 8g of divinylbenzene (mass content of 63%), 0.53g of benzoyl peroxide and 50.1g of toluene, adding the obtained organic phase (86mL) into the aqueous solution, stirring to form uniform-sized balls, starting heating, heating to 5 ℃ every 10 minutes, heating to 75 ℃ and reacting for 4 hours; continuously heating to 85 ℃, and curing for 12 h; after the reaction is finished, sequentially filtering, washing and drying the obtained materials (80 ℃, the time is 8 hours), extracting the obtained solid, and then sieving to obtain acrylic acid skeleton copolymer crosslinked microspheres with the granularity of 0.28-0.45 mm;

taking 10g of acrylic acid skeleton copolymer crosslinked microspheres, adding a mixed solution of 10mL of ethanol and 20mL of deionized water, fully swelling, dropwise adding 20g of picoline, starting stirring, reacting at 75 ℃ for 36h, washing the obtained product with methanol and deionized water in sequence, and drying to obtain the picoline resin.

Example 3

Adding 2.8g of gelatin into 280mL of deionized water, and heating to 55 ℃ until the gelatin is completely dispersed to obtain an aqueous solution; uniformly mixing 52g of methyl methacrylate, 10g of divinylbenzene (mass content of 63%), 0.62g of benzoyl peroxide and 58.4g of isooctane, adding the obtained organic phase (103.2mL) into the aqueous solution, stirring to form uniform-sized balls, starting heating, heating to 5 ℃ every 10 minutes, heating to 75 ℃ and reacting for 4 hours; continuously heating to 85 ℃, and curing for 12 h; after the reaction is finished, sequentially filtering, washing and drying the obtained materials (80 ℃, the time is 8 hours), extracting the obtained solid, and then sieving to obtain acrylic acid skeleton copolymer crosslinked microspheres with the granularity of 0.28-0.45 mm;

taking 10g of acrylic acid skeleton copolymer crosslinked microspheres, adding a mixed solution of 10mL of ethanol and 10mL of deionized water, dropwise adding 30g of picoline after full swelling, starting stirring, reacting at 85 ℃ for 48h, washing the obtained product with methanol and deionized water in sequence, and drying to obtain the picoline resin.

Characterization of

1) The acrylic acid skeleton copolymer crosslinked microspheres prepared in examples 1 to 3 and the picoline resin were subjected to elemental analysis and characterization, and the results are shown in table 1:

TABLE 1 data on the contents of the elements of the acrylic acid skeleton copolymer crosslinked microspheres and the picoline resins prepared in examples 1 to 3

As shown in Table 1, compared with the crosslinked microspheres of acrylic acid skeleton copolymer, the content of C, H, O element in the picoline resins prepared in examples 1-3 was decreased, while the N content of the picoline resin prepared in example 1 was increased to 6.3%, the N content of the picoline resin prepared in example 2 was increased to 10%, and the N content of the picoline resin prepared in example 3 was increased to 11.5%, which proves that picoline was successfully grafted to the resin.

Application example 1

1g of the picoline resin prepared in example 1 is put into 1L of uranium-containing wastewater (mine uranium-containing wastewater) with the uranium concentration of 300mg/L and the chloride radical concentration of 23g/L, pH value of 6.9 for single static adsorption, the adsorption time is 24h, after the adsorption is finished, the resin is taken out, calcined at 750 ℃ for 4h, and then uranyl ions are soaked and leached by 3mol/L of nitric acid, and the capacity of the adsorbed uranium on the resin is analyzed by ICP (inductively coupled plasma), and the result shows that the adsorption capacity of the picoline resin prepared in example 1 on the uranium is 76.3mg/g (dry resin).

Application example 2

2g of the picoline resin prepared in example 2 was placed in 2L of uranium-containing wastewater with a uranium concentration of 300mg/L and a chloride concentration of 23g/L, pH value of 6.9 for single static adsorption for 24h, and after adsorption was completed, the resin was taken out and the uranium capacity adsorbed on the resin was analyzed as in application example 1. The results showed that the picoline resin prepared in example 2 had an adsorption capacity of 88.42mg/g (dry resin) for uranium.

Application example 3

Taking 1g of the picoline resin prepared in example 3, placing the picoline resin into 1L of uranium-containing wastewater with the uranium concentration of 300mg/L and the chloride concentration of 23g/L, pH value of 6.9, carrying out single static adsorption for 24h, taking out the resin after adsorption is finished, and analyzing the uranium capacity adsorbed on the resin according to the method of application example 1; the results showed that the picoline resin prepared in example 3 had an adsorption capacity of 112.3mg/g (dry resin) for uranium.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.