A network polymer adsorbent based on triazine structure and its preparation method and application

Abstract

The present invention discloses a triazine-based reticular polymer adsorbent in the field of adsorbent technology, a preparation method and an application thereof. The present invention uses a triazine structure as a basic skeleton by introducing N + The basic skeleton is modified. The triazine structure has rich electron clouds and nitrogen atoms, and can form stable complexes with specific ions or molecules. Therefore, it has high selectivity and efficiency in adsorbing specific metal ions, organic pollutants, etc. It has strong thermal stability and antioxidant properties, and is suitable for use in harsh environmental conditions, especially in high temperature and acidic and alkaline environments.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorbents, and specifically relates to a triazine-based network polymer adsorbent and a preparation method and application thereof. Background Art

[0002] With the rapid development of society, the economy, and modern industry, humanity faces increasingly severe energy crises and environmental pollution. The rapid expansion of industry and agriculture has significantly increased demand for domestic and industrial water. However, due to factors such as water and soil pollution, the amount of toxic and hazardous substances (such as heavy metal ions and organic matter) in surface water is gradually increasing, making water purification increasingly difficult. Therefore, effective water pollution control is of vital importance to human production and daily life.

[0003] Adsorption is currently one of the most effective methods for addressing water pollution, offering advantages such as high adsorption capacity and reusable adsorbents. Due to its simple operation and wide range of applicability, adsorption is widely used. Currently, there are many known adsorbents, such as activated carbon, zeolite, montmorillonite, silica gel, and metal-organic frameworks. However, these adsorbents have disadvantages in practical applications, such as low adsorption capacity, high cost, poor selectivity, low efficiency, and limited recycling. Therefore, the development of adsorbent materials with superior adsorption properties is particularly important. Adsorbents are widely used in a variety of fields, including environmental protection, energy storage, drug release, and gas separation. The choice of adsorbent has a direct impact on factors such as the efficiency, selectivity, and cost of the adsorption process. Currently, researchers have proposed a variety of different adsorbent materials in the development of adsorbents, which can be divided into inorganic adsorbents, organic adsorbents, and composite adsorbents based on their structural characteristics. Inorganic adsorbents generally refer to mineral or metal oxide materials with excellent adsorption properties. For example, activated carbon, zeolite, silica gel, etc. are typical inorganic adsorbents. Inorganic adsorbents usually have a large specific surface area, can provide abundant adsorption sites, and maintain stable adsorption performance under high temperature conditions. Therefore, they are suitable for high temperature environments and are widely used in water treatment, air purification, gas adsorption and other fields. Inorganic adsorbents have poor selectivity and are usually unable to efficiently adsorb a specific pollutant. They may adsorb unwanted substances and reduce efficiency. Due to the complex surface properties of inorganic materials, the recovery of their adsorption capacity often requires higher temperatures or complex chemical treatments, resulting in high costs in the regeneration process; organic adsorbents include a variety of organic materials, such as common polymer resins, polymer adsorbents, etc. These materials are usually composed of synthetic organic molecules and have certain flexibility and adjustability. Organic adsorbents can optimize their selectivity for specific molecules by changing their molecular structure, enabling them to efficiently adsorb a specific substance. Compared with inorganic adsorbents, the preparation cost of organic adsorbents is usually lower. Many organic adsorbents are easily degraded in high temperature environments, which limits their application under high temperature conditions. Organic adsorbents may age due to long-term use, resulting in a decrease in adsorption performance. Composite adsorbents refer to a type of adsorbent that combines inorganic materials and organic materials to improve adsorption performance through synergistic effects.For example, adsorption materials formed by the combination of organic polymer materials and inorganic materials such as alumina and silica gel. Composite adsorbents can combine the high specific surface area and thermal stability of inorganic adsorbents, and utilize the high selectivity and adjustability of organic adsorbents to achieve better adsorption effects. Composite materials can be designed with a variety of adsorption sites according to demand to enhance their adsorption capacity for different types of pollutants. They usually have good durability and regeneration performance and can adapt to more complex environmental conditions. The preparation of composite adsorbents often requires more complex processes, which may involve multi-step reactions or physical methods, increasing the preparation cost. Due to the complex structure of the composite material, incompatibility problems may occur between different components, resulting in unstable performance. Summary of the Invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a network polymer adsorbent based on triazine structure and its preparation method and application. The present invention uses triazine structure as the basic skeleton and introduces N + The basic skeleton is modified. The triazine structure has rich electron clouds and nitrogen atoms, and can form stable complexes with specific ions or molecules. Therefore, it has high selectivity and efficiency in adsorbing specific metal ions and organic pollutants. It has strong thermal stability and antioxidant properties and is suitable for use in harsh environmental conditions, especially in high temperature and acidic environments.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: The present invention proposes a network polymer adsorbent based on a triazine structure, and the structural formula of the network polymer adsorbent is as follows:

[0006] ;

[0007] Preferably, in the structural formula of the network polymer adsorbent, X is one of chlorine and bromine;

[0008] Preferably, the structural formula of the network polymer adsorbent includes or does not include an R group;

[0009] Preferably, the structural formula of the network polymer adsorbent includes 、 、 、 、 、 、 、 One of the following;

[0010] The present invention also provides an application of a triazine-based network polymer adsorbent, and the application of the network polymer adsorbent in adsorbing heavy metal ions.

[0011] The present invention also provides an application of a triazine-based network polymer adsorbent, and the application of the network polymer adsorbent in adsorbing diclofenac sodium.

[0012] The present invention also provides a method for preparing a network polymer adsorbent based on a triazine structure, including a monomer-polymerization method and a one-pot method;

[0013] Preferably, the monomer-polymerization method specifically comprises the following steps:

[0014] Add monomer I to a reaction vessel, add a reaction solvent to fully dissolve it, add monomer II and mix it evenly, then raise the temperature under an inert gas atmosphere to carry out a first reaction, after the reaction is completed, cool, filter, wash and dry, transfer it to a reaction vessel, add a catalyst, mix it evenly, and raise the reaction temperature under inert gas protection to carry out a second reaction, after the reaction is completed, wash and dry to obtain a network polymer adsorbent;

[0015] Preferably, in the monomer-polymerization method, the reaction solvent comprises at least one of acetonitrile, DMSO, N-methylpyrrolidone, and tetrahydrofuran;

[0016] Preferably, in the monomer-polymerization method, the monomer I comprises one of 4-cyanobenzyl chloride and 4-cyanobenzyl bromide;

[0017] Preferably, in the monomer-polymerization method, the monomer II includes one of 4,4'-bipyridine, bis(4-pyridyl)amine, 4,4'-bipyridyl disulfide, 1,2-bis(4-pyridyl)ethylene, 4,4'-azopyridine, 3,6-bis(4-pyridyl)-1,2,4,5-tetrazine, 1,4-bis(p-pyridyl)benzene, 4,4'-bis(pyridin-4-yl)-1,1'-biphenyl, and 2,5-bis(pyridin-4-yl)thiophene;

[0018] Preferably, in the monomer-polymerization method, the molar ratio between the monomer I and the monomer II is 2-3:1;

[0019] Preferably, in the monomer-polymerization method, the temperature of the first reaction is 50-70° C., and the time of the first reaction is 24-36 h;

[0020] Preferably, in the monomer-polymerization method, the catalyst comprises at least one of trifluoromethanesulfonic acid, trifluoromethanesulfonic anhydride, and boron trifluoride;

[0021] Preferably, in the monomer-polymerization method, the amount of the catalyst added is 12%-20% by mass of the monomer I;

[0022] Preferably, in the monomer-polymerization method, the temperature of the second reaction is 100-120° C., and the time of the second reaction is 10-18 h.

[0023] Preferably, the one-pot method specifically comprises the following steps:

[0024] Under a nitrogen atmosphere, monomer III and monomer IV were added to the reaction flask in sequence. After adding the reaction solvent, the reaction temperature was increased and stirred for reaction. After the reaction was completed, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and vacuum dried to obtain a network polymer adsorbent;

[0025] Preferably, in the one-pot process, the molar ratio between monomer III and monomer IV is 1:1-2;

[0026] Preferably, in the one-pot process, the monomer III comprises one of 2,4,6-tris(4-chloromethylphenyl)-1,3,5-triazine and 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine;

[0027] Preferably, in the one-pot process, the monomer IV comprises one of 1,4-di(p-pyridyl)benzene, 4,4'-bipyridine, 3,6-di(4-pyridyl)-1,2,4,5-tetrazine, 1,2-di(4-pyridyl)ethylene, 4,4'-azopyridine, and 4,4'-bipyridine disulfide;

[0028] Preferably, in the one-pot process, the reaction solvent comprises at least one of acetonitrile, N-methylpyrrolidone, and tetrahydrofuran;

[0029] Preferably, in the one-pot process, the stirring reaction temperature is 80-100° C., and the stirring reaction time is 60-80 h.

[0030] The beneficial effects achieved by the present invention are as follows:

[0031] The present invention provides a triazine-based reticular polymer adsorbent and its preparation method and application, using the triazine structure as the basic skeleton by introducing N +The basic skeleton is modified. The triazine structure has rich electron clouds and nitrogen atoms and can form stable complexes with specific ions or molecules. Therefore, it has high selectivity and efficiency in adsorbing specific metal ions, organic pollutants, etc. It has strong thermal stability and antioxidant properties and is suitable for use in harsh environmental conditions, especially in high temperature and acidic environments. In the present invention, the central triazine ring is multi-point cross-linked with three aromatic chains to form a three-dimensional network structure. The skeleton has considerable rigidity and is not easy to collapse. The rigid polymer network can often maintain structural integrity during the swelling process or in organic solvents, thereby improving the cycle life and mechanical strength of the adsorbent. The triazine core and the external aromatic ring are linked by short and rigid connecting groups (R), forming regular gaps between molecules; at the same time, a large number of anion pairs (X - ) and positively charged sites (pyridinium or aniline) can induce uniform micropores or mesopores during self-assembly or swelling-drying processes. This tunable pore structure facilitates the rapid diffusion of macromolecules or metal complexes. Each arm of the structure carries a pyridinium cationic site, which efficiently captures anionic pollutants through electrostatic interactions. Furthermore, the aromatic triazine ring and side chain aromatic rings can form π-π structures with electron-rich π systems (such as phenols, aromatic amines, and dye-based pollutants), enhancing the adsorption capacity of organic molecules. The nitrogen atom pairs (-C=N-) on the triazine can form coordination bonds with certain transition metal ions, further enhancing the selective enrichment of metal ions. The core of the triazine structure itself is a nitrogen-heteroaromatic ring, which has a high thermal decomposition temperature (>350°C) and chemical inertness. The backbone remains intact in acidic or organic solvent environments, facilitating repeated recycling and regeneration under harsh conditions. The "R" groups on the aromatic arms can be modified with a variety of functional groups (carboxyl, amino, thiol, long-chain alkyl, etc.) through various chemical methods to adjust pore size distribution, modify hydrophilicity and hydrophobicity to optimize affinity for different target molecules, or introduce chirality or ligands to achieve selective adsorption of chiral molecules or specific metal ions. The triazine-based reticulated polymer adsorbent described in this invention, based on a triazine core reticulated polymer backbone, achieves the combined advantages of high specific surface area, high selectivity, high stability, and adjustable multifunctionality through the synergistic effects of high cross-linking, multiple charges, and an aromatic π system. It is particularly suitable for the efficient adsorption and separation of heavy metals, anionic dyes, and organic micropollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 FTIR image of the network polymer adsorbent prepared in Example 1 of the present invention;

[0033] Figure 2 This is a carbon NMR spectrum image of the network polymer adsorbent prepared in Example 1 of the present invention;

[0034] Figure 3This is the nitrogen adsorption-desorption isotherm of the network polymer adsorbent prepared in Example 1 of the present invention;

[0035] Figure 4 This is an SEM image of the network polymer adsorbent prepared in Example 1 of the present invention;

[0036] Figure 5 This is the XRD image of the network polymer adsorbent prepared in Example 1 of the present invention;

[0037] Figure 6 This is a physical picture of the network polymer adsorbent prepared in Example 1 of the present invention;

[0038] Figure 7 The network polymer adsorbent prepared in Example 1 adsorbs CrO4 2- UV-visible spectral images;

[0039] Figure 8 The prepared network polymer adsorbents of Examples 1, 5, and 7 are used for CrO4 2- Adsorption amount result graph;

[0040] Figure 9 The net-shaped high molecular polymer adsorbent prepared in Example 1 of the present invention is CrO4 2- Competitive adsorption performance results diagram;

[0041] Figure 10 This is a graph showing the recycling performance of the network polymer adsorbent prepared in Example 1 of the present invention;

[0042] Figure 11 This is a graph showing the adsorption performance of diclofenac sodium by the network polymer adsorbent prepared in Example 1 of the present invention.

[0043] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those familiar to those skilled in the art. Furthermore, any methods and materials similar or equivalent to those described herein can be applied to the present invention. The preferred embodiments and materials described herein are for illustrative purposes only and are not intended to limit the scope of this application.

[0046] The experimental methods in the following examples, unless otherwise specified, are conventional methods; the test materials and test strains used in the following examples, unless otherwise specified, are purchased from commercial channels.

[0047] Example 1

[0048] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0049] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 139 mg of 1,4-di(p-pyridyl)benzene were added to the reaction flask in sequence, and 15 mL of acetonitrile, a reaction solvent, was added. The mixture was then stirred at 100°C for 72 hours. After the reaction, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and vacuum dried at 80°C for 8 hours to obtain a network polymer adsorbent.

[0050] The molecular structure of the reticulated polymer adsorbent prepared in Example 1 was characterized using a Nicolet 6700 infrared spectrometer and an AVANCE III HD nuclear magnetic resonance spectrometer. The reticulated polymer adsorbent prepared in Example 1 was mixed with potassium bromide, ground, and flattened, and then subjected to infrared spectroscopy analysis in the scanning range of 4000-500 cm -1 , scanning frequency is 1cm -1 ; Figure 1 The FTIR image of the network polymer adsorbent prepared in Example 1 of the present invention is shown in the figure, 1633 cm -1 The signal at is the stretching vibration of the imine bond in the pyridine unit; Figure 2 This is the C NMR spectrum image of the reticulated polymer adsorbent prepared in Example 1 of the present invention. The signals at 64 ppm and 170 ppm are those of the methylene and triazine carbons, respectively. The above data demonstrate that the reticulated polymer adsorbent prepared in Example 1 of the present invention was successfully prepared.

[0051] The nitrogen adsorption-desorption isotherm of the reticulated polymer adsorbent prepared in Example 1 was measured using an Autosorb IQ-C physical adsorption instrument. Figure 3This is the nitrogen adsorption-desorption isotherm of the network high molecular polymer adsorbent prepared in Example 1 of the present invention. As shown in the figure, the network high molecular polymer adsorbent prepared in Example 1 of the present invention has a porous structure.

[0052] The microscopic morphology of the network polymer adsorbent prepared in Example 1 was analyzed using a FEI Quanta200 field emission environmental scanning electron microscope. Figure 4 This is a SEM image of the network polymer adsorbent prepared in Example 1 of the present invention. As shown in the figure, the network polymer adsorbent prepared in Example 1 has a stacked block morphology.

[0053] The X-ray diffraction analysis of the network polymer adsorbent prepared in Example 1 was performed using a VG Escalab MKII X-ray photoelectron spectrometer. Figure 5 The XRD pattern of the network polymer adsorbent prepared in Example 1 of the present invention is shown in the figure. There is a broad peak near 2Theta=25 and no other diffraction peaks, indicating that polymer 1 is an amorphous polymer. Figure 6 This is a physical picture of the network high molecular polymer adsorbent prepared in Example 1 of the present invention. As shown in the figure, the network high molecular polymer adsorbent prepared in the present invention is in powder form and has a yellow appearance.

[0054] Example 2

[0055] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0056] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.20g of 1,4-di(p-pyridyl)benzene. Mix the reaction system at 300rpm and raise the reaction temperature to 60℃. Continue stirring to carry out the first reaction. After 24h, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation. Filter and collect the solid. After repeated washing, the mixture was vacuum dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.1 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, the mixture was fully stirred at a speed of 500 rpm, the temperature was raised to 120°C, and the second reaction was carried out. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. After repeated washing with anhydrous ethanol and anhydrous methanol, the mixture was vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0057] Example 3

[0058] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0059] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.20g of 4,4'-bipyridine. Mix the reaction system at 300rpm and raise the reaction temperature to 60℃. Stir continuously to carry out the first reaction. After 24h of reaction, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing, the mixture was vacuum dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.09 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, and the mixture was fully stirred at 500 rpm. The temperature was raised to 120°C for the second reaction. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. After repeated washing with anhydrous ethanol and anhydrous methanol, the mixture was vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0060] Example 4

[0061] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0062] 4-cyanobenzyl bromide was placed in a flask, 30 mL of acetonitrile was added, and after 4-cyanobenzyl bromide was fully dissolved, nitrogen was introduced to replace the oxygen in the reaction environment, 0.15 g of bis(4-pyridyl)amine was added, and the reaction system was mixed uniformly at a speed of 300 rpm. The reaction temperature was raised to 60 ° C, and stirring was continued to carry out the first reaction. After the reaction was completed after 24 hours, the reaction was completed. After the reaction system was naturally cooled to room temperature, 100 mL of cold anhydrous ether was added as a precipitant for sedimentation treatment, and the solid was collected by suction filtration and repeatedly washed with anhydrous ethanol and anhydrous ether. After washing, vacuum drying at 50°C for 12 hours, transfer to a dry Schlenk flask, add 0.1g of trifluoromethanesulfonic acid, introduce flowing nitrogen until there is no oxygen in the reaction environment, stir thoroughly at 500rpm, raise the temperature to 120°C, carry out the second reaction, and terminate the reaction after 10 hours. After the reaction system is cooled to room temperature, wash with 0.1M NaOH until the trifluoromethanesulfonic acid is completely removed, wash repeatedly with anhydrous ethanol and anhydrous methanol, and vacuum dry at 60°C for 12 hours to obtain a network polymer adsorbent.

[0063] Example 5

[0064] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0065] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 111 mg of 4,4'-azopyridine were added to the reaction flask in sequence, and 20 mL of the reaction solvent N-methylpyrrolidone was added. The mixture was then stirred at 80°C for 72 hours. After the reaction, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and then vacuum dried at 80°C for 8 hours to obtain a network polymer adsorbent.

[0066] Example 6

[0067] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0068] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.24g of 4,4'-azopyridine. Mix the reaction system at 300rpm and raise the reaction temperature to 60℃. Stir continuously to carry out the first reaction. After 24h of reaction, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing, the mixture was vacuum dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.06 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, and the mixture was fully stirred at 500 rpm. The temperature was raised to 120°C for the second reaction. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. After repeated washing with anhydrous ethanol and anhydrous methanol, the mixture was vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0069] Example 7

[0070] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0071] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 109 mg of 1,2-di(4-pyridyl)ethylene were added to the reaction flask in sequence, and 20 mL of acetonitrile, a reaction solvent, was added. The mixture was then stirred at 80°C for 80 hours. After the reaction was completed, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and then vacuum dried at 80°C for 8 hours to obtain a network polymer adsorbent.

[0072] Example 8

[0073] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0074] Take 0.50g of 4-cyanobenzyl bromide and put it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.16g of 1,2-di(4-pyridyl)ethylene. Mix the reaction system at 300rpm and raise the reaction temperature to 60℃. Stir continuously to carry out the first reaction. After 24h of reaction, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing with ether and vacuum drying at 50°C for 12 hours, the mixture was transferred to a dry Schlenk flask, 0.1 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, the mixture was fully stirred at 500 rpm, the temperature was raised to 120°C, and the second reaction was carried out. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. The mixture was repeatedly washed with anhydrous ethanol and anhydrous methanol, and vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0075] Example 9

[0076] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0077] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 132 mg of 4,4'-bipyridyl disulfide were added to the reaction flask in sequence, and 20 mL of the reaction solvent N-methylpyrrolidone was added. The mixture was then stirred at 80°C for 60 hours. After the reaction was completed, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and then vacuum dried at 80°C for 8 hours to obtain a network polymer adsorbent.

[0078] Example 10

[0079] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0080] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.29g of 4,4'-bipyridyl disulfide. Mix the reaction system at 300rpm and raise the reaction temperature to 60°C. Stir continuously to carry out the first reaction. After 24h of reaction, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing with ether and vacuum drying at 50°C for 12 hours, the mixture was transferred to a dry Schlenk flask, 0.1 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, the mixture was fully stirred at a speed of 500 rpm, the temperature was raised to 120°C, and the second reaction was carried out. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. After repeated washing with anhydrous ethanol and anhydrous methanol, the mixture was vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0081] Example 11

[0082] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0083] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 142 mg of 3,6-di-4-pyridyl-1,2,4,5-tetrazine were added to the reaction flask in sequence, and 20 mL of the reaction solvent N-methylpyrrolidone was added. The mixture was then stirred at 100° C. for 72 hours. After the reaction, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and then vacuum dried at 80° C. for 8 hours to obtain a network polymer adsorbent.

[0084] Example 12

[0085] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0086] 0.50 g of 4-cyanobenzyl bromide was placed in a flask, 30 mL of acetonitrile was added, 4-cyanobenzyl bromide was fully dissolved, nitrogen was introduced to replace the oxygen in the reaction environment, 0.20 g of 3,6-di(4-pyridyl)-1,2,4,5-tetrazine was added, the reaction system was mixed uniformly at a speed of 300 rpm, the reaction temperature was increased to 60 ° C, stirring was continued, the first reaction was carried out, the reaction was completed after 24 hours, the reaction system was cooled to room temperature naturally, 100 mL of cold anhydrous ether was added as a precipitant for sedimentation treatment, the solid was collected by suction filtration, and the reaction mixture was washed with anhydrous ether. After repeated washing with alcohol and anhydrous ether, the mixture was vacuum dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.07 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, and the mixture was fully stirred at a speed of 500 rpm. The temperature was raised to 120°C for the second reaction. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. The mixture was repeatedly washed with anhydrous ethanol and anhydrous methanol, and vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0087] Example 13

[0088] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0089] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.21g of 2,5-di(pyridin-4-yl)thiophene. Mix the reaction system at a speed of 300rpm, raise the reaction temperature to 60°C, continue stirring, and carry out the first reaction. After the reaction is completed after 24h, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing with water and ether, the mixture was vacuum dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.1 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, the mixture was fully stirred at 500 rpm, the temperature was raised to 120°C, and the second reaction was carried out. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. The mixture was repeatedly washed with anhydrous ethanol and anhydrous methanol, and vacuum dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0090] Example 14

[0091] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a monomer-polymerization method, which specifically includes the following steps:

[0092] Take 0.50g of 4-cyanobenzyl bromide and place it in a flask. Add 30mL of acetonitrile. After fully dissolving 4-cyanobenzyl bromide, introduce nitrogen to replace the oxygen in the reaction environment. Add 0.27g of 4,4'-di(pyridin-4-yl)-1,1'-biphenyl. Mix the reaction system at 300rpm and raise the reaction temperature to 60℃. Stir continuously to carry out the first reaction. After 24h of reaction, the reaction is completed. After the reaction system is naturally cooled to room temperature, 100mL of cold anhydrous ether is added as a precipitant for sedimentation treatment. Filter and collect the solid. After repeated washing with anhydrous ether, it was vacuum-dried at 50°C for 12 hours, transferred to a dry Schlenk flask, 0.078 g of trifluoromethanesulfonic acid was added, flowing nitrogen was introduced until there was no oxygen in the reaction environment, and the mixture was fully stirred at a speed of 500 rpm. The temperature was raised to 120°C for the second reaction. After the reaction lasted for 10 hours, the reaction was completed. After the reaction system was cooled to room temperature, it was washed with 0.1 M NaOH until the trifluoromethanesulfonic acid was completely removed. After repeated washing with anhydrous ethanol and anhydrous methanol, it was vacuum-dried at 60°C for 12 hours to obtain a network polymer adsorbent.

[0093] Example 15

[0094] This embodiment provides a method for preparing a triazine-based network polymer adsorbent, using a one-pot process, which specifically includes the following steps:

[0095] Under a nitrogen atmosphere, 235 mg of 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine and 99 mg of 4,4'-bipyridine were added to the reaction flask in sequence, and 15 mL of the reaction solvent N-methylpyrrolidone was added. The mixture was then stirred at 100°C for 72 hours. After the reaction, the generated solid was filtered and washed with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and then vacuum dried at 80°C for 8 hours to obtain a network polymer adsorbent.

[0096] Experimental Example 1

[0097] This experimental example tests the adsorption performance of K2CrO4 on the network polymer adsorbents prepared in Examples 1, 5, and 7:

[0098] 1. A K2CrO4 aqueous solution was prepared at a concentration of 0.2 g / L, and the network polymer agent prepared in Example 1 was added to the K2CrO4 aqueous solution at a concentration of 0.6 mg / mL. The mixture was fully stirred at a speed of 500 rpm, and the sampling times were set to 0 min, 0.5 min, 0.7 min, 1 min, 2 min, 4 min, 8 min, 16 min and 30 min for sampling. The mixed solution was filtered with a needle filter (0.22 µm), and the ultraviolet absorption peak of the filtrate was measured using a UV-visible spectrophotometer. The adsorption efficiency was determined by comparing the intensity of the ultraviolet characteristic absorption peak before and after adsorption.

[0099] Figure 7 The network polymer adsorbent prepared in Example 1 adsorbs CrO4 2- UV-visible spectrum image, as shown in the figure, as time increases, CrO4 in the solution 2- The UV absorption peak intensity of CrO4 gradually decreased. 2- The intensity of the characteristic absorption peak is close to the baseline, indicating that polymer 1 can quickly and effectively adsorb CrO4 in water. 2- .

[0100] 2. Take the network high molecular polymer adsorbent prepared in Example 1, Example 5 and Example 7, add 0.8 mg / mL to different concentrations of K2CrO4 aqueous solution, set the concentration of K2CrO4 aqueous solution to 0.05 mg / L, 0.1 mg / L, 0.2 mg / L, 0.3 mg / L, 0.4 mg / L and 0.5 mg / L, stir thoroughly at 500 rpm, sample after 20 minutes, filter the mixture with a needle filter (0.22 μm), measure the ultraviolet absorption peak of the filtrate with a UV-visible spectrophotometer, and calculate the CrO4 absorption of the network high molecular polymer adsorbent prepared in Example 1, Example 5 and Example 7 by comparing the ultraviolet characteristic absorption peak intensity before and after adsorption. 2- The maximum adsorption capacity.

[0101] Figure 8 The prepared network polymer adsorbents of Examples 1, 5, and 7 are used for CrO4 2- The adsorption results are shown in the figure. After fitting the adsorption data with the LangmuirEX1 model, it can be concluded that the network polymer adsorbent prepared in Example 1 has a high adsorption capacity for CrO4. 2- The maximum adsorption capacity of the network polymer adsorbent prepared in Example 5 is 168 mg / g for CrO4 2- The maximum adsorption capacity of the network polymer adsorbent prepared in Example 7 is 129 mg / g for CrO4 2- The maximum adsorption capacity is 161 mg / g.

[0102] 3. The adsorption of CrO4 by the network polymer adsorbent prepared in Example 1 2- Competitive adsorption performance test: the network polymer adsorbent prepared in Example 1 was added to a K2CrO4 0.2g / L mixed aqueous solution at a concentration of 0.6mg / mL. The mixed aqueous solution contained the following concentrations of other anions: HCO3 - 2g / L, Cl - 2g / L, Br - 2g / L, NO3 - 2g / L, I - 2g / L; set up a control group without other anions; stir thoroughly at 500rpm, filter the mixture with a needle filter (0.22µm) after adsorption saturation, measure the ultraviolet absorption peak of the filtrate with a UV-visible spectrophotometer, and calculate the absorption of CrO4 by the network polymer adsorbent under different anion competition. 2- adsorption rate.

[0103] Figure 9 The net-shaped high molecular polymer adsorbent prepared in Example 1 of the present invention is CrO4 2- Competitive adsorption performance results are shown in the figure. Under the condition of 10 times competitive anion, the network polymer adsorbent prepared in Example 1 can still effectively adsorb CrO4 2- , the adsorption rate is above 80%.

[0104] 4. Take the network polymer adsorbent prepared in Example 1 and add it to the K2CrO40.2g / L mixed aqueous solution at a concentration of 0.6mg / mL, stir it thoroughly at a speed of 500rpm, and after saturation, filter the mixture with filter paper to obtain the solid adsorbed CrO4. 2- The reticulated polymer adsorbent was washed with KBr solution until the filtrate was colorless to achieve regeneration. After drying, it could be recycled and added to a K2CrO4 0.2g / L mixed aqueous solution at a concentration of 0.6mg / mL for secondary adsorption. After the cycles, the adsorption of CrO4 by the reticulated polymer adsorbent prepared in Example 1 was determined and calculated. 2- adsorption rate.

[0105] Figure 10 The results of the recycle performance of the network polymer adsorbent prepared in Example 1 are shown in the figure. As shown in the figure, the network polymer adsorbent prepared in Example 1 can adsorb CrO4 after 5 cycles. 2- The post-adsorption efficiency is still above 80%, indicating that polymer 1 has excellent stability and recycling performance.

[0106] Experimental Example 2

[0107] In this experimental example, the adsorption performance of diclofenac sodium was tested on the reticulated polymer adsorbent prepared in Example 1: the reticulated polymer adsorbent prepared in Example 1 was added to aqueous diclofenac sodium solutions at a concentration of 0.8 g / L, wherein the concentrations of the aqueous diclofenac sodium solutions were 0.4 g / L, 0.6 g / L, 0.8 g / L, 1.0 g / L, 1.2 g / L, and 1.4 g / L. The mixture was stirred at 500 rpm. After saturation adsorption, the mixture was filtered through a syringe filter (0.22 µm). The ultraviolet absorption peak of the filtrate was measured using a UV-visible spectrophotometer, and the adsorption rate of diclofenac sodium by the reticulated polymer adsorbent under different anion competition was calculated.

[0108] Figure 11 The adsorption performance of the reticulated polymer adsorbent prepared in Example 1 of the present invention for diclofenac sodium is shown in the figure. After fitting the adsorption data with the LangmuirEX1 model, it can be concluded that the maximum adsorption capacity of the reticulated polymer adsorbent prepared in Example 1 for diclofenac sodium is 866 mg / g.

[0109] While the embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that various changes, modifications, substitutions, and alterations can be made to the embodiments without departing from the principles and spirit of the invention.

[0110] The present invention and its embodiments are described above. Such description is not restrictive. The drawings show only one embodiment of the present invention, and actual applications are not limited thereto. In short, if a person skilled in the art is inspired by the above, and does not deviate from the purpose of the present invention, any method and embodiment similar to the technical solution without creative design shall fall within the scope of protection of the present invention.

Claims

1. A triazine-based network polymer adsorbent, characterized by: The structural formula of the network polymer adsorbent is as follows: ； In the structural formula of the network polymer adsorbent, X is one of chlorine and bromine; In the structural formula of the network polymer adsorbent, R includes 、 、 、 、 、 、 、 One of them.

2. The use of a triazine-based network polymer adsorbent according to claim 1, characterized in that: The network polymer adsorbent selectively adsorbs CrO4 2- or, the application of the network polymer adsorbent in adsorbing diclofenac sodium.

3. The method for preparing a triazine-based network polymer adsorbent according to claim 1, wherein: Including monomer-polymerization method or one-pot method; The monomer-polymerization method specifically comprises the following steps: adding monomer I to a reaction vessel, adding a reaction solvent to fully dissolve it, adding monomer II and mixing it uniformly, raising the temperature under an inert gas atmosphere to carry out a first reaction, cooling, filtering, washing and drying after the reaction is completed, transferring it to a reaction vessel, adding a catalyst, mixing it uniformly, raising the reaction temperature under the protection of inert gas to carry out a second reaction, and washing and drying after the reaction is completed to obtain a network polymer adsorbent; In the monomer-polymerization method, the monomer I includes one of 4-cyanobenzyl chloride and 4-cyanobenzyl bromide; the monomer II includes one of bis(4-pyridyl)amine, 4,4'-bipyridyl disulfide, 1,2-bis(4-pyridyl)ethylene, 4,4'-azopyridine, 3,6-bis(4-pyridyl)-1,2,4,5-tetrazine, 1,4-bis(p-pyridyl)benzene, 4,4'-bis(pyridin-4-yl)-1,1'-biphenyl, and 2,5-bis(pyridin-4-yl)thiophene; The one-pot method specifically comprises the following steps: under a nitrogen atmosphere, sequentially adding monomer III and monomer IV to a reaction flask, adding a reaction solvent, raising the reaction temperature and stirring the reaction, after the reaction is completed, filtering the generated solid, and washing it with dichloromethane, tetrahydrofuran, ethanol and acetone in sequence, and vacuum drying to obtain a network polymer adsorbent; The monomer III includes one of 2,4,6-tris(4-chloromethylphenyl)-1,3,5-triazine and 2,4,6-tris(4-bromomethylphenyl)-1,3,5-triazine; the monomer IV includes one of 1,4-di(p-pyridyl)benzene, 3,6-di(4-pyridyl)-1,2,4,5-tetrazine, 1,2-di(4-pyridyl)ethylene, 4,4'-azopyridine, and 4,4'-bipyridyl disulfide.

4. The method for preparing a triazine-based network polymer adsorbent according to claim 3, characterized in that: In the monomer-polymerization method, the reaction solvent includes at least one of acetonitrile, DMSO, N-methylpyrrolidone, and tetrahydrofuran; and the catalyst includes at least one of trifluoromethanesulfonic acid, trifluoromethanesulfonic anhydride, and boron trifluoride.

5. The method for preparing a triazine-based network polymer adsorbent according to claim 4, characterized in that: In the monomer-polymerization method, the molar ratio between the monomer I and the monomer II is 2-3:1; and the added amount of the catalyst is 12%-20% of the mass of the monomer I.

6. The method for preparing a triazine-based network polymer adsorbent according to claim 5, characterized in that: In the monomer-polymerization method, the temperature of the first reaction is 50-70° C., and the time of the first reaction is 24-36 hours; in the monomer-polymerization method, the temperature of the second reaction is 100-120° C., and the time of the second reaction is 10-18 hours.

7. The method for preparing a triazine-based network polymer adsorbent according to claim 6, characterized in that: In the one-pot method, the reaction solvent includes at least one of acetonitrile, N-methylpyrrolidone, and tetrahydrofuran.

8. The method for preparing a triazine-based network polymer adsorbent according to claim 7, characterized in that: In the one-pot process, the molar ratio of monomer III to monomer IV is 1:1-2; in the one-pot process, the stirring reaction temperature is 80-100° C., and the stirring reaction time is 60-80 h.

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